Merge tag 'tty-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial driver updates from Greg KH:
 "Here is the big tty/serial driver update for 4.3-rc1.

  Not many major things, a number of driver updates and changes, and the
  8250 driver got split up a bit to make it easier to work with by
  moving some functions to a new file.  Full details are in the
  shortlog.

  All have been in linux-next with no reported issues"

* tag 'tty-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (90 commits)
  serial: imx: save and restore context in the suspend path
  serial: imx: allow waking up on RTSD
  serial: imx: introduce serial_imx_enable_wakeup()
  serial: imx: remove unbalanced clk_prepare
  serial: 8250: move rx_running out of the bitfield
  tty: serial: 8250_omap: do not use RX DMA if pause is not supported
  serial:8250_dw: do not alter CTS and DCTS since AFE is enabled
  tty: serial: men_z135_uart.c: Don't initialize port->lock
  tty: serial: men_z135_uart.c: Fix race between IRQ and set_termios()
  serial: 8250: bind to ALi Fast Infrared Controller (ALI5123)
  serial: 8250: don't bind to SMSC IrCC IR port
  serial: mxs-auart: fix baud rate range
  serial: mxs-auart: keep the AUART unit in reset state when not in use
  serial: mxs-auart: use a function name to reflect what it really does
  serial: 8250_pci: fix mode after S3/S4 resume for F81504/508/512
  sc16is7xx: constify devtype
  sc16is7xx: support multiple devices
  sc16is7xx: save and use per-chip line number
  uart: pl011: Add support to ZTE ZX296702 uart
  uart: pl011: Improve LCRH register access decision
  ...

Documentation/devicetree/bindings/serial/atmel-usart.txt

@@ -22,6 +22,8 @@ Optional properties:
 		memory peripheral interface and USART DMA channel ID, FIFO configuration.
 		Refer to dma.txt and atmel-dma.txt for details.
 	- dma-names: "rx" for RX channel, "tx" for TX channel.
+- atmel,fifo-size: maximum number of data the RX and TX FIFOs can store for FIFO
+  capable USARTs.
 
 <chip> compatible description:
 - at91rm9200:  legacy USART support
@@ -57,4 +59,5 @@ Example:
 		dmas = <&dma0 2 0x3>,
 		       <&dma0 2 0x204>;
 		dma-names = "tx", "rx";
+		atmel,fifo-size = <32>;
 	};

Documentation/devicetree/bindings/serial/axis,etraxfs-uart.txt

@@ -6,7 +6,7 @@ Required properties:
 - interrupts: device interrupt
 
 Optional properties:
-- {dtr,dsr,ri,cd}-gpios: specify a GPIO for DTR/DSR/RI/CD
+- {dtr,dsr,rng,dcd}-gpios: specify a GPIO for DTR/DSR/RI/DCD
   line respectively.
 
 Example:
@@ -16,4 +16,8 @@ serial@b00260000 {
 	reg = <0xb0026000 0x1000>;
 	interrupts = <68>;
 	status = "disabled";
+	dtr-gpios = <&sysgpio 0 GPIO_ACTIVE_LOW>;
+	dsr-gpios = <&sysgpio 1 GPIO_ACTIVE_LOW>;
+	rng-gpios = <&sysgpio 2 GPIO_ACTIVE_LOW>;
+	dcd-gpios = <&sysgpio 3 GPIO_ACTIVE_LOW>;
 };

Documentation/devicetree/bindings/serial/omap_serial.txt

@@ -4,6 +4,9 @@ Required properties:
 - compatible : should be "ti,omap2-uart" for OMAP2 controllers
 - compatible : should be "ti,omap3-uart" for OMAP3 controllers
 - compatible : should be "ti,omap4-uart" for OMAP4 controllers
+- compatible : should be "ti,am4372-uart" for AM437x controllers
+- compatible : should be "ti,am3352-uart" for AM335x controllers
+- compatible : should be "ti,dra742-uart" for DRA7x controllers
 - reg : address and length of the register space
 - interrupts or interrupts-extended : Should contain the uart interrupt
                                       specifier or both the interrupt

arch/arm/boot/dts/am33xx.dtsi

@@ -210,7 +210,7 @@
 		};
 
 		uart0: serial@44e09000 {
-			compatible = "ti,omap3-uart";
+			compatible = "ti,am3352-uart", "ti,omap3-uart";
 			ti,hwmods = "uart1";
 			clock-frequency = <48000000>;
 			reg = <0x44e09000 0x2000>;
@@ -221,7 +221,7 @@
 		};
 
 		uart1: serial@48022000 {
-			compatible = "ti,omap3-uart";
+			compatible = "ti,am3352-uart", "ti,omap3-uart";
 			ti,hwmods = "uart2";
 			clock-frequency = <48000000>;
 			reg = <0x48022000 0x2000>;
@@ -232,7 +232,7 @@
 		};
 
 		uart2: serial@48024000 {
-			compatible = "ti,omap3-uart";
+			compatible = "ti,am3352-uart", "ti,omap3-uart";
 			ti,hwmods = "uart3";
 			clock-frequency = <48000000>;
 			reg = <0x48024000 0x2000>;
@@ -243,7 +243,7 @@
 		};
 
 		uart3: serial@481a6000 {
-			compatible = "ti,omap3-uart";
+			compatible = "ti,am3352-uart", "ti,omap3-uart";
 			ti,hwmods = "uart4";
 			clock-frequency = <48000000>;
 			reg = <0x481a6000 0x2000>;
@@ -252,7 +252,7 @@
 		};
 
 		uart4: serial@481a8000 {
-			compatible = "ti,omap3-uart";
+			compatible = "ti,am3352-uart", "ti,omap3-uart";
 			ti,hwmods = "uart5";
 			clock-frequency = <48000000>;
 			reg = <0x481a8000 0x2000>;
@@ -261,7 +261,7 @@
 		};
 
 		uart5: serial@481aa000 {
-			compatible = "ti,omap3-uart";
+			compatible = "ti,am3352-uart", "ti,omap3-uart";
 			ti,hwmods = "uart6";
 			clock-frequency = <48000000>;
 			reg = <0x481aa000 0x2000>;

arch/arm/boot/dts/dra7.dtsi

@@ -397,7 +397,7 @@
 		};
 
 		uart1: serial@4806a000 {
-			compatible = "ti,omap4-uart";
+			compatible = "ti,dra742-uart", "ti,omap4-uart";
 			reg = <0x4806a000 0x100>;
 			interrupts-extended = <&crossbar_mpu GIC_SPI 67 IRQ_TYPE_LEVEL_HIGH>;
 			ti,hwmods = "uart1";
@@ -408,7 +408,7 @@
 		};
 
 		uart2: serial@4806c000 {
-			compatible = "ti,omap4-uart";
+			compatible = "ti,dra742-uart", "ti,omap4-uart";
 			reg = <0x4806c000 0x100>;
 			interrupts = <GIC_SPI 68 IRQ_TYPE_LEVEL_HIGH>;
 			ti,hwmods = "uart2";
@@ -419,7 +419,7 @@
 		};
 
 		uart3: serial@48020000 {
-			compatible = "ti,omap4-uart";
+			compatible = "ti,dra742-uart", "ti,omap4-uart";
 			reg = <0x48020000 0x100>;
 			interrupts = <GIC_SPI 69 IRQ_TYPE_LEVEL_HIGH>;
 			ti,hwmods = "uart3";
@@ -430,7 +430,7 @@
 		};
 
 		uart4: serial@4806e000 {
-			compatible = "ti,omap4-uart";
+			compatible = "ti,dra742-uart", "ti,omap4-uart";
 			reg = <0x4806e000 0x100>;
 			interrupts = <GIC_SPI 65 IRQ_TYPE_LEVEL_HIGH>;
 			ti,hwmods = "uart4";
@@ -441,7 +441,7 @@
 		};
 
 		uart5: serial@48066000 {
-			compatible = "ti,omap4-uart";
+			compatible = "ti,dra742-uart", "ti,omap4-uart";
 			reg = <0x48066000 0x100>;
 			interrupts = <GIC_SPI 100 IRQ_TYPE_LEVEL_HIGH>;
 			ti,hwmods = "uart5";
@@ -452,7 +452,7 @@
 		};
 
 		uart6: serial@48068000 {
-			compatible = "ti,omap4-uart";
+			compatible = "ti,dra742-uart", "ti,omap4-uart";
 			reg = <0x48068000 0x100>;
 			interrupts = <GIC_SPI 101 IRQ_TYPE_LEVEL_HIGH>;
 			ti,hwmods = "uart6";
@@ -463,7 +463,7 @@
 		};
 
 		uart7: serial@48420000 {
-			compatible = "ti,omap4-uart";
+			compatible = "ti,dra742-uart", "ti,omap4-uart";
 			reg = <0x48420000 0x100>;
 			interrupts = <GIC_SPI 218 IRQ_TYPE_LEVEL_HIGH>;
 			ti,hwmods = "uart7";
@@ -472,7 +472,7 @@
 		};
 
 		uart8: serial@48422000 {
-			compatible = "ti,omap4-uart";
+			compatible = "ti,dra742-uart", "ti,omap4-uart";
 			reg = <0x48422000 0x100>;
 			interrupts = <GIC_SPI 219 IRQ_TYPE_LEVEL_HIGH>;
 			ti,hwmods = "uart8";
@@ -481,7 +481,7 @@
 		};
 
 		uart9: serial@48424000 {
-			compatible = "ti,omap4-uart";
+			compatible = "ti,dra742-uart", "ti,omap4-uart";
 			reg = <0x48424000 0x100>;
 			interrupts = <GIC_SPI 220 IRQ_TYPE_LEVEL_HIGH>;
 			ti,hwmods = "uart9";
@@ -490,7 +490,7 @@
 		};
 
 		uart10: serial@4ae2b000 {
-			compatible = "ti,omap4-uart";
+			compatible = "ti,dra742-uart", "ti,omap4-uart";
 			reg = <0x4ae2b000 0x100>;
 			interrupts = <GIC_SPI 221 IRQ_TYPE_LEVEL_HIGH>;
 			ti,hwmods = "uart10";

drivers/acpi/acpi_pnp.c

@@ -153,6 +153,7 @@ static const struct acpi_device_id acpi_pnp_device_ids[] = {
 	{"AEI0250"},		/* PROLiNK 1456VH ISA PnP K56flex Fax Modem */
 	{"AEI1240"},		/* Actiontec ISA PNP 56K X2 Fax Modem */
 	{"AKY1021"},		/* Rockwell 56K ACF II Fax+Data+Voice Modem */
+	{"ALI5123"},		/* ALi Fast Infrared Controller */
 	{"AZT4001"},		/* AZT3005 PnP SOUND DEVICE */
 	{"BDP3336"},		/* Best Data Products Inc. Smart One 336F PnP Modem */
 	{"BRI0A49"},		/* Boca Complete Ofc Communicator 14.4 Data-FAX */

drivers/tty/n_gsm.c

@@ -2712,7 +2712,7 @@ static void gsm_mux_rx_netchar(struct gsm_dlci *dlci,
 	memcpy(skb_put(skb, size), in_buf, size);
 
 	skb->dev = net;
-	skb->protocol = __constant_htons(ETH_P_IP);
+	skb->protocol = htons(ETH_P_IP);
 
 	/* Ship it off to the kernel */
 	netif_rx(skb);

drivers/tty/n_tty.c

@@ -2147,6 +2147,8 @@ extern ssize_t redirected_tty_write(struct file *, const char __user *,
 
 static int job_control(struct tty_struct *tty, struct file *file)
 {
+	struct pid *pgrp;
+
 	/* Job control check -- must be done at start and after
 	   every sleep (POSIX.1 7.1.1.4). */
 	/* NOTE: not yet done after every sleep pending a thorough
@@ -2156,18 +2158,25 @@ static int job_control(struct tty_struct *tty, struct file *file)
 	    current->signal->tty != tty)
 		return 0;
 
+	rcu_read_lock();
+	pgrp = task_pgrp(current);
+
 	spin_lock_irq(&tty->ctrl_lock);
 	if (!tty->pgrp)
 		printk(KERN_ERR "n_tty_read: no tty->pgrp!\n");
-	else if (task_pgrp(current) != tty->pgrp) {
+	else if (pgrp != tty->pgrp) {
 		spin_unlock_irq(&tty->ctrl_lock);
-		if (is_ignored(SIGTTIN) || is_current_pgrp_orphaned())
+		if (is_ignored(SIGTTIN) || is_current_pgrp_orphaned()) {
+			rcu_read_unlock();
 			return -EIO;
-		kill_pgrp(task_pgrp(current), SIGTTIN, 1);
+		}
+		kill_pgrp(pgrp, SIGTTIN, 1);
+		rcu_read_unlock();
 		set_thread_flag(TIF_SIGPENDING);
 		return -ERESTARTSYS;
 	}
 	spin_unlock_irq(&tty->ctrl_lock);
+	rcu_read_unlock();
 	return 0;
 }
 

drivers/tty/pty.c

@@ -26,6 +26,12 @@
 #include <linux/mutex.h>
 #include <linux/poll.h>
 
+#undef TTY_DEBUG_HANGUP
+#ifdef TTY_DEBUG_HANGUP
+# define tty_debug_hangup(tty, f, args...)	tty_debug(tty, f, ##args)
+#else
+# define tty_debug_hangup(tty, f, args...)	do {} while (0)
+#endif
 
 #ifdef CONFIG_UNIX98_PTYS
 static struct tty_driver *ptm_driver;
@@ -779,6 +785,8 @@ static int ptmx_open(struct inode *inode, struct file *filp)
 	if (retval)
 		goto err_release;
 
+	tty_debug_hangup(tty, "(tty count=%d)\n", tty->count);
+
 	tty_unlock(tty);
 	return 0;
 err_release:

drivers/tty/serial/8250/8250.h

@@ -42,9 +42,9 @@ struct uart_8250_dma {
 	size_t			rx_size;
 	size_t			tx_size;
 
-	unsigned char		tx_running:1;
-	unsigned char		tx_err: 1;
-	unsigned char		rx_running:1;
+	unsigned char		tx_running;
+	unsigned char		tx_err;
+	unsigned char		rx_running;
 };
 
 struct old_serial_port {
@@ -211,3 +211,14 @@ static inline int ns16550a_goto_highspeed(struct uart_8250_port *up)
 	}
 	return 1;
 }
+
+static inline int serial_index(struct uart_port *port)
+{
+	return port->minor - 64;
+}
+
+#if 0
+#define DEBUG_INTR(fmt...)	printk(fmt)
+#else
+#define DEBUG_INTR(fmt...)	do { } while (0)
+#endif

drivers/tty/serial/8250/8250_core.c

@@ -1,25 +1,23 @@
 /*
- *  Driver for 8250/16550-type serial ports
+ *  Universal/legacy driver for 8250/16550-type serial ports
  *
  *  Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
  *
  *  Copyright (C) 2001 Russell King.
  *
+ *  Supports: ISA-compatible 8250/16550 ports
+ *	      PNP 8250/16550 ports
+ *	      early_serial_setup() ports
+ *	      userspace-configurable "phantom" ports
+ *	      "serial8250" platform devices
+ *	      serial8250_register_8250_port() ports
+ *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.
- *
- * A note about mapbase / membase
- *
- *  mapbase is the physical address of the IO port.
- *  membase is an 'ioremapped' cookie.
  */
 
-#if defined(CONFIG_SERIAL_8250_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
-#define SUPPORT_SYSRQ
-#endif
-
 #include <linux/module.h>
 #include <linux/moduleparam.h>
 #include <linux/ioport.h>
@@ -58,33 +56,10 @@ static unsigned int nr_uarts = CONFIG_SERIAL_8250_RUNTIME_UARTS;
 
 static struct uart_driver serial8250_reg;
 
-static int serial_index(struct uart_port *port)
-{
-	return port->minor - 64;
-}
-
 static unsigned int skip_txen_test; /* force skip of txen test at init time */
 
-/*
- * Debugging.
- */
-#if 0
-#define DEBUG_AUTOCONF(fmt...)	printk(fmt)
-#else
-#define DEBUG_AUTOCONF(fmt...)	do { } while (0)
-#endif
-
-#if 0
-#define DEBUG_INTR(fmt...)	printk(fmt)
-#else
-#define DEBUG_INTR(fmt...)	do { } while (0)
-#endif
-
 #define PASS_LIMIT	512
 
-#define BOTH_EMPTY 	(UART_LSR_TEMT | UART_LSR_THRE)
-
-
 #include <asm/serial.h>
 /*
  * SERIAL_PORT_DFNS tells us about built-in ports that have no
@@ -120,2695 +95,268 @@ static struct hlist_head irq_lists[NR_IRQ_HASH];
 static DEFINE_MUTEX(hash_mutex);	/* Used to walk the hash */
 
 /*
- * Here we define the default xmit fifo size used for each type of UART.
+ * This is the serial driver's interrupt routine.
+ *
+ * Arjan thinks the old way was overly complex, so it got simplified.
+ * Alan disagrees, saying that need the complexity to handle the weird
+ * nature of ISA shared interrupts.  (This is a special exception.)
+ *
+ * In order to handle ISA shared interrupts properly, we need to check
+ * that all ports have been serviced, and therefore the ISA interrupt
+ * line has been de-asserted.
+ *
+ * This means we need to loop through all ports. checking that they
+ * don't have an interrupt pending.
  */
-static const struct serial8250_config uart_config[] = {
-	[PORT_UNKNOWN] = {
-		.name		= "unknown",
-		.fifo_size	= 1,
-		.tx_loadsz	= 1,
-	},
-	[PORT_8250] = {
-		.name		= "8250",
-		.fifo_size	= 1,
-		.tx_loadsz	= 1,
-	},
-	[PORT_16450] = {
-		.name		= "16450",
-		.fifo_size	= 1,
-		.tx_loadsz	= 1,
-	},
-	[PORT_16550] = {
-		.name		= "16550",
-		.fifo_size	= 1,
-		.tx_loadsz	= 1,
-	},
-	[PORT_16550A] = {
-		.name		= "16550A",
-		.fifo_size	= 16,
-		.tx_loadsz	= 16,
-		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
-		.rxtrig_bytes	= {1, 4, 8, 14},
-		.flags		= UART_CAP_FIFO,
-	},
-	[PORT_CIRRUS] = {
-		.name		= "Cirrus",
-		.fifo_size	= 1,
-		.tx_loadsz	= 1,
-	},
-	[PORT_16650] = {
-		.name		= "ST16650",
-		.fifo_size	= 1,
-		.tx_loadsz	= 1,
-		.flags		= UART_CAP_FIFO | UART_CAP_EFR | UART_CAP_SLEEP,
-	},
-	[PORT_16650V2] = {
-		.name		= "ST16650V2",
-		.fifo_size	= 32,
-		.tx_loadsz	= 16,
-		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_01 |
-				  UART_FCR_T_TRIG_00,
-		.rxtrig_bytes	= {8, 16, 24, 28},
-		.flags		= UART_CAP_FIFO | UART_CAP_EFR | UART_CAP_SLEEP,
-	},
-	[PORT_16750] = {
-		.name		= "TI16750",
-		.fifo_size	= 64,
-		.tx_loadsz	= 64,
-		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10 |
-				  UART_FCR7_64BYTE,
-		.rxtrig_bytes	= {1, 16, 32, 56},
-		.flags		= UART_CAP_FIFO | UART_CAP_SLEEP | UART_CAP_AFE,
-	},
-	[PORT_STARTECH] = {
-		.name		= "Startech",
-		.fifo_size	= 1,
-		.tx_loadsz	= 1,
-	},
-	[PORT_16C950] = {
-		.name		= "16C950/954",
-		.fifo_size	= 128,
-		.tx_loadsz	= 128,
-		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
-		/* UART_CAP_EFR breaks billionon CF bluetooth card. */
-		.flags		= UART_CAP_FIFO | UART_CAP_SLEEP,
-	},
-	[PORT_16654] = {
-		.name		= "ST16654",
-		.fifo_size	= 64,
-		.tx_loadsz	= 32,
-		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_01 |
-				  UART_FCR_T_TRIG_10,
-		.rxtrig_bytes	= {8, 16, 56, 60},
-		.flags		= UART_CAP_FIFO | UART_CAP_EFR | UART_CAP_SLEEP,
-	},
-	[PORT_16850] = {
-		.name		= "XR16850",
-		.fifo_size	= 128,
-		.tx_loadsz	= 128,
-		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
-		.flags		= UART_CAP_FIFO | UART_CAP_EFR | UART_CAP_SLEEP,
-	},
-	[PORT_RSA] = {
-		.name		= "RSA",
-		.fifo_size	= 2048,
-		.tx_loadsz	= 2048,
-		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_11,
-		.flags		= UART_CAP_FIFO,
-	},
-	[PORT_NS16550A] = {
-		.name		= "NS16550A",
-		.fifo_size	= 16,
-		.tx_loadsz	= 16,
-		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
-		.flags		= UART_CAP_FIFO | UART_NATSEMI,
-	},
-	[PORT_XSCALE] = {
-		.name		= "XScale",
-		.fifo_size	= 32,
-		.tx_loadsz	= 32,
-		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
-		.flags		= UART_CAP_FIFO | UART_CAP_UUE | UART_CAP_RTOIE,
-	},
-	[PORT_OCTEON] = {
-		.name		= "OCTEON",
-		.fifo_size	= 64,
-		.tx_loadsz	= 64,
-		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
-		.flags		= UART_CAP_FIFO,
-	},
-	[PORT_AR7] = {
-		.name		= "AR7",
-		.fifo_size	= 16,
-		.tx_loadsz	= 16,
-		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_00,
-		.flags		= UART_CAP_FIFO | UART_CAP_AFE,
-	},
-	[PORT_U6_16550A] = {
-		.name		= "U6_16550A",
-		.fifo_size	= 64,
-		.tx_loadsz	= 64,
-		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
-		.flags		= UART_CAP_FIFO | UART_CAP_AFE,
-	},
-	[PORT_TEGRA] = {
-		.name		= "Tegra",
-		.fifo_size	= 32,
-		.tx_loadsz	= 8,
-		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_01 |
-				  UART_FCR_T_TRIG_01,
-		.rxtrig_bytes	= {1, 4, 8, 14},
-		.flags		= UART_CAP_FIFO | UART_CAP_RTOIE,
-	},
-	[PORT_XR17D15X] = {
-		.name		= "XR17D15X",
-		.fifo_size	= 64,
-		.tx_loadsz	= 64,
-		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
-		.flags		= UART_CAP_FIFO | UART_CAP_AFE | UART_CAP_EFR |
-				  UART_CAP_SLEEP,
-	},
-	[PORT_XR17V35X] = {
-		.name		= "XR17V35X",
-		.fifo_size	= 256,
-		.tx_loadsz	= 256,
-		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_11 |
-				  UART_FCR_T_TRIG_11,
-		.flags		= UART_CAP_FIFO | UART_CAP_AFE | UART_CAP_EFR |
-				  UART_CAP_SLEEP,
-	},
-	[PORT_LPC3220] = {
-		.name		= "LPC3220",
-		.fifo_size	= 64,
-		.tx_loadsz	= 32,
-		.fcr		= UART_FCR_DMA_SELECT | UART_FCR_ENABLE_FIFO |
-				  UART_FCR_R_TRIG_00 | UART_FCR_T_TRIG_00,
-		.flags		= UART_CAP_FIFO,
-	},
-	[PORT_BRCM_TRUMANAGE] = {
-		.name		= "TruManage",
-		.fifo_size	= 1,
-		.tx_loadsz	= 1024,
-		.flags		= UART_CAP_HFIFO,
-	},
-	[PORT_8250_CIR] = {
-		.name		= "CIR port"
-	},
-	[PORT_ALTR_16550_F32] = {
-		.name		= "Altera 16550 FIFO32",
-		.fifo_size	= 32,
-		.tx_loadsz	= 32,
-		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
-		.flags		= UART_CAP_FIFO | UART_CAP_AFE,
-	},
-	[PORT_ALTR_16550_F64] = {
-		.name		= "Altera 16550 FIFO64",
-		.fifo_size	= 64,
-		.tx_loadsz	= 64,
-		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
-		.flags		= UART_CAP_FIFO | UART_CAP_AFE,
-	},
-	[PORT_ALTR_16550_F128] = {
-		.name		= "Altera 16550 FIFO128",
-		.fifo_size	= 128,
-		.tx_loadsz	= 128,
-		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
-		.flags		= UART_CAP_FIFO | UART_CAP_AFE,
-	},
-/* tx_loadsz is set to 63-bytes instead of 64-bytes to implement
-workaround of errata A-008006 which states that tx_loadsz should  be
-configured less than Maximum supported fifo bytes */
-	[PORT_16550A_FSL64] = {
-		.name		= "16550A_FSL64",
-		.fifo_size	= 64,
-		.tx_loadsz	= 63,
-		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10 |
-				  UART_FCR7_64BYTE,
-		.flags		= UART_CAP_FIFO,
-	},
-};
-
-/* Uart divisor latch read */
-static int default_serial_dl_read(struct uart_8250_port *up)
-{
-	return serial_in(up, UART_DLL) | serial_in(up, UART_DLM) << 8;
-}
-
-/* Uart divisor latch write */
-static void default_serial_dl_write(struct uart_8250_port *up, int value)
-{
-	serial_out(up, UART_DLL, value & 0xff);
-	serial_out(up, UART_DLM, value >> 8 & 0xff);
-}
-
-#if defined(CONFIG_MIPS_ALCHEMY) || defined(CONFIG_SERIAL_8250_RT288X)
-
-/* Au1x00/RT288x UART hardware has a weird register layout */
-static const s8 au_io_in_map[8] = {
-	 0,	/* UART_RX  */
-	 2,	/* UART_IER */
-	 3,	/* UART_IIR */
-	 5,	/* UART_LCR */
-	 6,	/* UART_MCR */
-	 7,	/* UART_LSR */
-	 8,	/* UART_MSR */
-	-1,	/* UART_SCR (unmapped) */
-};
-
-static const s8 au_io_out_map[8] = {
-	 1,	/* UART_TX  */
-	 2,	/* UART_IER */
-	 4,	/* UART_FCR */
-	 5,	/* UART_LCR */
-	 6,	/* UART_MCR */
-	-1,	/* UART_LSR (unmapped) */
-	-1,	/* UART_MSR (unmapped) */
-	-1,	/* UART_SCR (unmapped) */
-};
-
-static unsigned int au_serial_in(struct uart_port *p, int offset)
-{
-	if (offset >= ARRAY_SIZE(au_io_in_map))
-		return UINT_MAX;
-	offset = au_io_in_map[offset];
-	if (offset < 0)
-		return UINT_MAX;
-	return __raw_readl(p->membase + (offset << p->regshift));
-}
-
-static void au_serial_out(struct uart_port *p, int offset, int value)
-{
-	if (offset >= ARRAY_SIZE(au_io_out_map))
-		return;
-	offset = au_io_out_map[offset];
-	if (offset < 0)
-		return;
-	__raw_writel(value, p->membase + (offset << p->regshift));
-}
-
-/* Au1x00 haven't got a standard divisor latch */
-static int au_serial_dl_read(struct uart_8250_port *up)
+static irqreturn_t serial8250_interrupt(int irq, void *dev_id)
 {
-	return __raw_readl(up->port.membase + 0x28);
-}
+	struct irq_info *i = dev_id;
+	struct list_head *l, *end = NULL;
+	int pass_counter = 0, handled = 0;
 
-static void au_serial_dl_write(struct uart_8250_port *up, int value)
-{
-	__raw_writel(value, up->port.membase + 0x28);
-}
+	DEBUG_INTR("serial8250_interrupt(%d)...", irq);
 
-#endif
+	spin_lock(&i->lock);
 
-static unsigned int hub6_serial_in(struct uart_port *p, int offset)
-{
-	offset = offset << p->regshift;
-	outb(p->hub6 - 1 + offset, p->iobase);
-	return inb(p->iobase + 1);
-}
+	l = i->head;
+	do {
+		struct uart_8250_port *up;
+		struct uart_port *port;
 
-static void hub6_serial_out(struct uart_port *p, int offset, int value)
-{
-	offset = offset << p->regshift;
-	outb(p->hub6 - 1 + offset, p->iobase);
-	outb(value, p->iobase + 1);
-}
+		up = list_entry(l, struct uart_8250_port, list);
+		port = &up->port;
 
-static unsigned int mem_serial_in(struct uart_port *p, int offset)
-{
-	offset = offset << p->regshift;
-	return readb(p->membase + offset);
-}
+		if (port->handle_irq(port)) {
+			handled = 1;
+			end = NULL;
+		} else if (end == NULL)
+			end = l;
 
-static void mem_serial_out(struct uart_port *p, int offset, int value)
-{
-	offset = offset << p->regshift;
-	writeb(value, p->membase + offset);
-}
+		l = l->next;
 
-static void mem32_serial_out(struct uart_port *p, int offset, int value)
-{
-	offset = offset << p->regshift;
-	writel(value, p->membase + offset);
-}
+		if (l == i->head && pass_counter++ > PASS_LIMIT) {
+			/* If we hit this, we're dead. */
+			printk_ratelimited(KERN_ERR
+				"serial8250: too much work for irq%d\n", irq);
+			break;
+		}
+	} while (l != end);
 
-static unsigned int mem32_serial_in(struct uart_port *p, int offset)
-{
-	offset = offset << p->regshift;
-	return readl(p->membase + offset);
-}
+	spin_unlock(&i->lock);
 
-static void mem32be_serial_out(struct uart_port *p, int offset, int value)
-{
-	offset = offset << p->regshift;
-	iowrite32be(value, p->membase + offset);
-}
+	DEBUG_INTR("end.\n");
 
-static unsigned int mem32be_serial_in(struct uart_port *p, int offset)
-{
-	offset = offset << p->regshift;
-	return ioread32be(p->membase + offset);
+	return IRQ_RETVAL(handled);
 }
 
-static unsigned int io_serial_in(struct uart_port *p, int offset)
+/*
+ * To support ISA shared interrupts, we need to have one interrupt
+ * handler that ensures that the IRQ line has been deasserted
+ * before returning.  Failing to do this will result in the IRQ
+ * line being stuck active, and, since ISA irqs are edge triggered,
+ * no more IRQs will be seen.
+ */
+static void serial_do_unlink(struct irq_info *i, struct uart_8250_port *up)
 {
-	offset = offset << p->regshift;
-	return inb(p->iobase + offset);
-}
+	spin_lock_irq(&i->lock);
 
-static void io_serial_out(struct uart_port *p, int offset, int value)
-{
-	offset = offset << p->regshift;
-	outb(value, p->iobase + offset);
+	if (!list_empty(i->head)) {
+		if (i->head == &up->list)
+			i->head = i->head->next;
+		list_del(&up->list);
+	} else {
+		BUG_ON(i->head != &up->list);
+		i->head = NULL;
+	}
+	spin_unlock_irq(&i->lock);
+	/* List empty so throw away the hash node */
+	if (i->head == NULL) {
+		hlist_del(&i->node);
+		kfree(i);
+	}
 }
 
-static int serial8250_default_handle_irq(struct uart_port *port);
-static int exar_handle_irq(struct uart_port *port);
-
-static void set_io_from_upio(struct uart_port *p)
+static int serial_link_irq_chain(struct uart_8250_port *up)
 {
-	struct uart_8250_port *up = up_to_u8250p(p);
-
-	up->dl_read = default_serial_dl_read;
-	up->dl_write = default_serial_dl_write;
+	struct hlist_head *h;
+	struct hlist_node *n;
+	struct irq_info *i;
+	int ret, irq_flags = up->port.flags & UPF_SHARE_IRQ ? IRQF_SHARED : 0;
 
-	switch (p->iotype) {
-	case UPIO_HUB6:
-		p->serial_in = hub6_serial_in;
-		p->serial_out = hub6_serial_out;
-		break;
+	mutex_lock(&hash_mutex);
 
-	case UPIO_MEM:
-		p->serial_in = mem_serial_in;
-		p->serial_out = mem_serial_out;
-		break;
+	h = &irq_lists[up->port.irq % NR_IRQ_HASH];
 
-	case UPIO_MEM32:
-		p->serial_in = mem32_serial_in;
-		p->serial_out = mem32_serial_out;
-		break;
+	hlist_for_each(n, h) {
+		i = hlist_entry(n, struct irq_info, node);
+		if (i->irq == up->port.irq)
+			break;
+	}
 
-	case UPIO_MEM32BE:
-		p->serial_in = mem32be_serial_in;
-		p->serial_out = mem32be_serial_out;
-		break;
+	if (n == NULL) {
+		i = kzalloc(sizeof(struct irq_info), GFP_KERNEL);
+		if (i == NULL) {
+			mutex_unlock(&hash_mutex);
+			return -ENOMEM;
+		}
+		spin_lock_init(&i->lock);
+		i->irq = up->port.irq;
+		hlist_add_head(&i->node, h);
+	}
+	mutex_unlock(&hash_mutex);
 
-#if defined(CONFIG_MIPS_ALCHEMY) || defined(CONFIG_SERIAL_8250_RT288X)
-	case UPIO_AU:
-		p->serial_in = au_serial_in;
-		p->serial_out = au_serial_out;
-		up->dl_read = au_serial_dl_read;
-		up->dl_write = au_serial_dl_write;
-		break;
-#endif
+	spin_lock_irq(&i->lock);
 
-	default:
-		p->serial_in = io_serial_in;
-		p->serial_out = io_serial_out;
-		break;
-	}
-	/* Remember loaded iotype */
-	up->cur_iotype = p->iotype;
-	p->handle_irq = serial8250_default_handle_irq;
-}
+	if (i->head) {
+		list_add(&up->list, i->head);
+		spin_unlock_irq(&i->lock);
 
-static void
-serial_port_out_sync(struct uart_port *p, int offset, int value)
-{
-	switch (p->iotype) {
-	case UPIO_MEM:
-	case UPIO_MEM32:
-	case UPIO_MEM32BE:
-	case UPIO_AU:
-		p->serial_out(p, offset, value);
-		p->serial_in(p, UART_LCR);	/* safe, no side-effects */
-		break;
-	default:
-		p->serial_out(p, offset, value);
+		ret = 0;
+	} else {
+		INIT_LIST_HEAD(&up->list);
+		i->head = &up->list;
+		spin_unlock_irq(&i->lock);
+		irq_flags |= up->port.irqflags;
+		ret = request_irq(up->port.irq, serial8250_interrupt,
+				  irq_flags, "serial", i);
+		if (ret < 0)
+			serial_do_unlink(i, up);
 	}
-}
 
-/*
- * For the 16C950
- */
-static void serial_icr_write(struct uart_8250_port *up, int offset, int value)
-{
-	serial_out(up, UART_SCR, offset);
-	serial_out(up, UART_ICR, value);
+	return ret;
 }
 
-static unsigned int serial_icr_read(struct uart_8250_port *up, int offset)
+static void serial_unlink_irq_chain(struct uart_8250_port *up)
 {
-	unsigned int value;
+	/*
+	 * yes, some broken gcc emit "warning: 'i' may be used uninitialized"
+	 * but no, we are not going to take a patch that assigns NULL below.
+	 */
+	struct irq_info *i;
+	struct hlist_node *n;
+	struct hlist_head *h;
 
-	serial_icr_write(up, UART_ACR, up->acr | UART_ACR_ICRRD);
-	serial_out(up, UART_SCR, offset);
-	value = serial_in(up, UART_ICR);
-	serial_icr_write(up, UART_ACR, up->acr);
+	mutex_lock(&hash_mutex);
 
-	return value;
-}
+	h = &irq_lists[up->port.irq % NR_IRQ_HASH];
 
-/*
- * FIFO support.
- */
-static void serial8250_clear_fifos(struct uart_8250_port *p)
-{
-	if (p->capabilities & UART_CAP_FIFO) {
-		serial_out(p, UART_FCR, UART_FCR_ENABLE_FIFO);
-		serial_out(p, UART_FCR, UART_FCR_ENABLE_FIFO |
-			       UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
-		serial_out(p, UART_FCR, 0);
+	hlist_for_each(n, h) {
+		i = hlist_entry(n, struct irq_info, node);
+		if (i->irq == up->port.irq)
+			break;
 	}
-}
 
-void serial8250_clear_and_reinit_fifos(struct uart_8250_port *p)
-{
-	serial8250_clear_fifos(p);
-	serial_out(p, UART_FCR, p->fcr);
-}
-EXPORT_SYMBOL_GPL(serial8250_clear_and_reinit_fifos);
+	BUG_ON(n == NULL);
+	BUG_ON(i->head == NULL);
 
-void serial8250_rpm_get(struct uart_8250_port *p)
-{
-	if (!(p->capabilities & UART_CAP_RPM))
-		return;
-	pm_runtime_get_sync(p->port.dev);
-}
-EXPORT_SYMBOL_GPL(serial8250_rpm_get);
+	if (list_empty(i->head))
+		free_irq(up->port.irq, i);
 
-void serial8250_rpm_put(struct uart_8250_port *p)
-{
-	if (!(p->capabilities & UART_CAP_RPM))
-		return;
-	pm_runtime_mark_last_busy(p->port.dev);
-	pm_runtime_put_autosuspend(p->port.dev);
+	serial_do_unlink(i, up);
+	mutex_unlock(&hash_mutex);
 }
-EXPORT_SYMBOL_GPL(serial8250_rpm_put);
 
 /*
- * These two wrappers ensure that enable_runtime_pm_tx() can be called more than
- * once and disable_runtime_pm_tx() will still disable RPM because the fifo is
- * empty and the HW can idle again.
+ * This function is used to handle ports that do not have an
+ * interrupt.  This doesn't work very well for 16450's, but gives
+ * barely passable results for a 16550A.  (Although at the expense
+ * of much CPU overhead).
  */
-static void serial8250_rpm_get_tx(struct uart_8250_port *p)
+static void serial8250_timeout(unsigned long data)
 {
-	unsigned char rpm_active;
-
-	if (!(p->capabilities & UART_CAP_RPM))
-		return;
+	struct uart_8250_port *up = (struct uart_8250_port *)data;
 
-	rpm_active = xchg(&p->rpm_tx_active, 1);
-	if (rpm_active)
-		return;
-	pm_runtime_get_sync(p->port.dev);
+	up->port.handle_irq(&up->port);
+	mod_timer(&up->timer, jiffies + uart_poll_timeout(&up->port));
 }
 
-static void serial8250_rpm_put_tx(struct uart_8250_port *p)
+static void serial8250_backup_timeout(unsigned long data)
 {
-	unsigned char rpm_active;
+	struct uart_8250_port *up = (struct uart_8250_port *)data;
+	unsigned int iir, ier = 0, lsr;
+	unsigned long flags;
 
-	if (!(p->capabilities & UART_CAP_RPM))
-		return;
-
-	rpm_active = xchg(&p->rpm_tx_active, 0);
-	if (!rpm_active)
-		return;
-	pm_runtime_mark_last_busy(p->port.dev);
-	pm_runtime_put_autosuspend(p->port.dev);
-}
-
-/*
- * IER sleep support.  UARTs which have EFRs need the "extended
- * capability" bit enabled.  Note that on XR16C850s, we need to
- * reset LCR to write to IER.
- */
-static void serial8250_set_sleep(struct uart_8250_port *p, int sleep)
-{
-	unsigned char lcr = 0, efr = 0;
-	/*
-	 * Exar UARTs have a SLEEP register that enables or disables
-	 * each UART to enter sleep mode separately.  On the XR17V35x the
-	 * register is accessible to each UART at the UART_EXAR_SLEEP
-	 * offset but the UART channel may only write to the corresponding
-	 * bit.
-	 */
-	serial8250_rpm_get(p);
-	if ((p->port.type == PORT_XR17V35X) ||
-	   (p->port.type == PORT_XR17D15X)) {
-		serial_out(p, UART_EXAR_SLEEP, sleep ? 0xff : 0);
-		goto out;
-	}
-
-	if (p->capabilities & UART_CAP_SLEEP) {
-		if (p->capabilities & UART_CAP_EFR) {
-			lcr = serial_in(p, UART_LCR);
-			efr = serial_in(p, UART_EFR);
-			serial_out(p, UART_LCR, UART_LCR_CONF_MODE_B);
-			serial_out(p, UART_EFR, UART_EFR_ECB);
-			serial_out(p, UART_LCR, 0);
-		}
-		serial_out(p, UART_IER, sleep ? UART_IERX_SLEEP : 0);
-		if (p->capabilities & UART_CAP_EFR) {
-			serial_out(p, UART_LCR, UART_LCR_CONF_MODE_B);
-			serial_out(p, UART_EFR, efr);
-			serial_out(p, UART_LCR, lcr);
-		}
-	}
-out:
-	serial8250_rpm_put(p);
-}
-
-#ifdef CONFIG_SERIAL_8250_RSA
-/*
- * Attempts to turn on the RSA FIFO.  Returns zero on failure.
- * We set the port uart clock rate if we succeed.
- */
-static int __enable_rsa(struct uart_8250_port *up)
-{
-	unsigned char mode;
-	int result;
-
-	mode = serial_in(up, UART_RSA_MSR);
-	result = mode & UART_RSA_MSR_FIFO;
-
-	if (!result) {
-		serial_out(up, UART_RSA_MSR, mode | UART_RSA_MSR_FIFO);
-		mode = serial_in(up, UART_RSA_MSR);
-		result = mode & UART_RSA_MSR_FIFO;
-	}
-
-	if (result)
-		up->port.uartclk = SERIAL_RSA_BAUD_BASE * 16;
-
-	return result;
-}
-
-static void enable_rsa(struct uart_8250_port *up)
-{
-	if (up->port.type == PORT_RSA) {
-		if (up->port.uartclk != SERIAL_RSA_BAUD_BASE * 16) {
-			spin_lock_irq(&up->port.lock);
-			__enable_rsa(up);
-			spin_unlock_irq(&up->port.lock);
-		}
-		if (up->port.uartclk == SERIAL_RSA_BAUD_BASE * 16)
-			serial_out(up, UART_RSA_FRR, 0);
-	}
-}
-
-/*
- * Attempts to turn off the RSA FIFO.  Returns zero on failure.
- * It is unknown why interrupts were disabled in here.  However,
- * the caller is expected to preserve this behaviour by grabbing
- * the spinlock before calling this function.
- */
-static void disable_rsa(struct uart_8250_port *up)
-{
-	unsigned char mode;
-	int result;
-
-	if (up->port.type == PORT_RSA &&
-	    up->port.uartclk == SERIAL_RSA_BAUD_BASE * 16) {
-		spin_lock_irq(&up->port.lock);
-
-		mode = serial_in(up, UART_RSA_MSR);
-		result = !(mode & UART_RSA_MSR_FIFO);
-
-		if (!result) {
-			serial_out(up, UART_RSA_MSR, mode & ~UART_RSA_MSR_FIFO);
-			mode = serial_in(up, UART_RSA_MSR);
-			result = !(mode & UART_RSA_MSR_FIFO);
-		}
-
-		if (result)
-			up->port.uartclk = SERIAL_RSA_BAUD_BASE_LO * 16;
-		spin_unlock_irq(&up->port.lock);
-	}
-}
-#endif /* CONFIG_SERIAL_8250_RSA */
-
-/*
- * This is a quickie test to see how big the FIFO is.
- * It doesn't work at all the time, more's the pity.
- */
-static int size_fifo(struct uart_8250_port *up)
-{
-	unsigned char old_fcr, old_mcr, old_lcr;
-	unsigned short old_dl;
-	int count;
-
-	old_lcr = serial_in(up, UART_LCR);
-	serial_out(up, UART_LCR, 0);
-	old_fcr = serial_in(up, UART_FCR);
-	old_mcr = serial_in(up, UART_MCR);
-	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
-		    UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
-	serial_out(up, UART_MCR, UART_MCR_LOOP);
-	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
-	old_dl = serial_dl_read(up);
-	serial_dl_write(up, 0x0001);
-	serial_out(up, UART_LCR, 0x03);
-	for (count = 0; count < 256; count++)
-		serial_out(up, UART_TX, count);
-	mdelay(20);/* FIXME - schedule_timeout */
-	for (count = 0; (serial_in(up, UART_LSR) & UART_LSR_DR) &&
-	     (count < 256); count++)
-		serial_in(up, UART_RX);
-	serial_out(up, UART_FCR, old_fcr);
-	serial_out(up, UART_MCR, old_mcr);
-	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
-	serial_dl_write(up, old_dl);
-	serial_out(up, UART_LCR, old_lcr);
-
-	return count;
-}
-
-/*
- * Read UART ID using the divisor method - set DLL and DLM to zero
- * and the revision will be in DLL and device type in DLM.  We
- * preserve the device state across this.
- */
-static unsigned int autoconfig_read_divisor_id(struct uart_8250_port *p)
-{
-	unsigned char old_dll, old_dlm, old_lcr;
-	unsigned int id;
-
-	old_lcr = serial_in(p, UART_LCR);
-	serial_out(p, UART_LCR, UART_LCR_CONF_MODE_A);
-
-	old_dll = serial_in(p, UART_DLL);
-	old_dlm = serial_in(p, UART_DLM);
-
-	serial_out(p, UART_DLL, 0);
-	serial_out(p, UART_DLM, 0);
-
-	id = serial_in(p, UART_DLL) | serial_in(p, UART_DLM) << 8;
-
-	serial_out(p, UART_DLL, old_dll);
-	serial_out(p, UART_DLM, old_dlm);
-	serial_out(p, UART_LCR, old_lcr);
-
-	return id;
-}
-
-/*
- * This is a helper routine to autodetect StarTech/Exar/Oxsemi UART's.
- * When this function is called we know it is at least a StarTech
- * 16650 V2, but it might be one of several StarTech UARTs, or one of
- * its clones.  (We treat the broken original StarTech 16650 V1 as a
- * 16550, and why not?  Startech doesn't seem to even acknowledge its
- * existence.)
- *
- * What evil have men's minds wrought...
- */
-static void autoconfig_has_efr(struct uart_8250_port *up)
-{
-	unsigned int id1, id2, id3, rev;
-
-	/*
-	 * Everything with an EFR has SLEEP
-	 */
-	up->capabilities |= UART_CAP_EFR | UART_CAP_SLEEP;
-
-	/*
-	 * First we check to see if it's an Oxford Semiconductor UART.
-	 *
-	 * If we have to do this here because some non-National
-	 * Semiconductor clone chips lock up if you try writing to the
-	 * LSR register (which serial_icr_read does)
-	 */
-
-	/*
-	 * Check for Oxford Semiconductor 16C950.
-	 *
-	 * EFR [4] must be set else this test fails.
-	 *
-	 * This shouldn't be necessary, but Mike Hudson (Exoray@isys.ca)
-	 * claims that it's needed for 952 dual UART's (which are not
-	 * recommended for new designs).
-	 */
-	up->acr = 0;
-	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
-	serial_out(up, UART_EFR, UART_EFR_ECB);
-	serial_out(up, UART_LCR, 0x00);
-	id1 = serial_icr_read(up, UART_ID1);
-	id2 = serial_icr_read(up, UART_ID2);
-	id3 = serial_icr_read(up, UART_ID3);
-	rev = serial_icr_read(up, UART_REV);
-
-	DEBUG_AUTOCONF("950id=%02x:%02x:%02x:%02x ", id1, id2, id3, rev);
-
-	if (id1 == 0x16 && id2 == 0xC9 &&
-	    (id3 == 0x50 || id3 == 0x52 || id3 == 0x54)) {
-		up->port.type = PORT_16C950;
-
-		/*
-		 * Enable work around for the Oxford Semiconductor 952 rev B
-		 * chip which causes it to seriously miscalculate baud rates
-		 * when DLL is 0.
-		 */
-		if (id3 == 0x52 && rev == 0x01)
-			up->bugs |= UART_BUG_QUOT;
-		return;
-	}
-
-	/*
-	 * We check for a XR16C850 by setting DLL and DLM to 0, and then
-	 * reading back DLL and DLM.  The chip type depends on the DLM
-	 * value read back:
-	 *  0x10 - XR16C850 and the DLL contains the chip revision.
-	 *  0x12 - XR16C2850.
-	 *  0x14 - XR16C854.
-	 */
-	id1 = autoconfig_read_divisor_id(up);
-	DEBUG_AUTOCONF("850id=%04x ", id1);
-
-	id2 = id1 >> 8;
-	if (id2 == 0x10 || id2 == 0x12 || id2 == 0x14) {
-		up->port.type = PORT_16850;
-		return;
-	}
-
-	/*
-	 * It wasn't an XR16C850.
-	 *
-	 * We distinguish between the '654 and the '650 by counting
-	 * how many bytes are in the FIFO.  I'm using this for now,
-	 * since that's the technique that was sent to me in the
-	 * serial driver update, but I'm not convinced this works.
-	 * I've had problems doing this in the past.  -TYT
-	 */
-	if (size_fifo(up) == 64)
-		up->port.type = PORT_16654;
-	else
-		up->port.type = PORT_16650V2;
-}
-
-/*
- * We detected a chip without a FIFO.  Only two fall into
- * this category - the original 8250 and the 16450.  The
- * 16450 has a scratch register (accessible with LCR=0)
- */
-static void autoconfig_8250(struct uart_8250_port *up)
-{
-	unsigned char scratch, status1, status2;
-
-	up->port.type = PORT_8250;
-
-	scratch = serial_in(up, UART_SCR);
-	serial_out(up, UART_SCR, 0xa5);
-	status1 = serial_in(up, UART_SCR);
-	serial_out(up, UART_SCR, 0x5a);
-	status2 = serial_in(up, UART_SCR);
-	serial_out(up, UART_SCR, scratch);
-
-	if (status1 == 0xa5 && status2 == 0x5a)
-		up->port.type = PORT_16450;
-}
-
-static int broken_efr(struct uart_8250_port *up)
-{
-	/*
-	 * Exar ST16C2550 "A2" devices incorrectly detect as
-	 * having an EFR, and report an ID of 0x0201.  See
-	 * http://linux.derkeiler.com/Mailing-Lists/Kernel/2004-11/4812.html
-	 */
-	if (autoconfig_read_divisor_id(up) == 0x0201 && size_fifo(up) == 16)
-		return 1;
-
-	return 0;
-}
-
-/*
- * We know that the chip has FIFOs.  Does it have an EFR?  The
- * EFR is located in the same register position as the IIR and
- * we know the top two bits of the IIR are currently set.  The
- * EFR should contain zero.  Try to read the EFR.
- */
-static void autoconfig_16550a(struct uart_8250_port *up)
-{
-	unsigned char status1, status2;
-	unsigned int iersave;
-
-	up->port.type = PORT_16550A;
-	up->capabilities |= UART_CAP_FIFO;
-
-	/*
-	 * XR17V35x UARTs have an extra divisor register, DLD
-	 * that gets enabled with when DLAB is set which will
-	 * cause the device to incorrectly match and assign
-	 * port type to PORT_16650.  The EFR for this UART is
-	 * found at offset 0x09. Instead check the Deice ID (DVID)
-	 * register for a 2, 4 or 8 port UART.
-	 */
-	if (up->port.flags & UPF_EXAR_EFR) {
-		status1 = serial_in(up, UART_EXAR_DVID);
-		if (status1 == 0x82 || status1 == 0x84 || status1 == 0x88) {
-			DEBUG_AUTOCONF("Exar XR17V35x ");
-			up->port.type = PORT_XR17V35X;
-			up->capabilities |= UART_CAP_AFE | UART_CAP_EFR |
-						UART_CAP_SLEEP;
-
-			return;
-		}
-
-	}
-
-	/*
-	 * Check for presence of the EFR when DLAB is set.
-	 * Only ST16C650V1 UARTs pass this test.
-	 */
-	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
-	if (serial_in(up, UART_EFR) == 0) {
-		serial_out(up, UART_EFR, 0xA8);
-		if (serial_in(up, UART_EFR) != 0) {
-			DEBUG_AUTOCONF("EFRv1 ");
-			up->port.type = PORT_16650;
-			up->capabilities |= UART_CAP_EFR | UART_CAP_SLEEP;
-		} else {
-			serial_out(up, UART_LCR, 0);
-			serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
-				   UART_FCR7_64BYTE);
-			status1 = serial_in(up, UART_IIR) >> 5;
-			serial_out(up, UART_FCR, 0);
-			serial_out(up, UART_LCR, 0);
-
-			if (status1 == 7)
-				up->port.type = PORT_16550A_FSL64;
-			else
-				DEBUG_AUTOCONF("Motorola 8xxx DUART ");
-		}
-		serial_out(up, UART_EFR, 0);
-		return;
-	}
-
-	/*
-	 * Maybe it requires 0xbf to be written to the LCR.
-	 * (other ST16C650V2 UARTs, TI16C752A, etc)
-	 */
-	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
-	if (serial_in(up, UART_EFR) == 0 && !broken_efr(up)) {
-		DEBUG_AUTOCONF("EFRv2 ");
-		autoconfig_has_efr(up);
-		return;
-	}
-
-	/*
-	 * Check for a National Semiconductor SuperIO chip.
-	 * Attempt to switch to bank 2, read the value of the LOOP bit
-	 * from EXCR1. Switch back to bank 0, change it in MCR. Then
-	 * switch back to bank 2, read it from EXCR1 again and check
-	 * it's changed. If so, set baud_base in EXCR2 to 921600. -- dwmw2
-	 */
-	serial_out(up, UART_LCR, 0);
-	status1 = serial_in(up, UART_MCR);
-	serial_out(up, UART_LCR, 0xE0);
-	status2 = serial_in(up, 0x02); /* EXCR1 */
-
-	if (!((status2 ^ status1) & UART_MCR_LOOP)) {
-		serial_out(up, UART_LCR, 0);
-		serial_out(up, UART_MCR, status1 ^ UART_MCR_LOOP);
-		serial_out(up, UART_LCR, 0xE0);
-		status2 = serial_in(up, 0x02); /* EXCR1 */
-		serial_out(up, UART_LCR, 0);
-		serial_out(up, UART_MCR, status1);
-
-		if ((status2 ^ status1) & UART_MCR_LOOP) {
-			unsigned short quot;
-
-			serial_out(up, UART_LCR, 0xE0);
-
-			quot = serial_dl_read(up);
-			quot <<= 3;
-
-			if (ns16550a_goto_highspeed(up))
-				serial_dl_write(up, quot);
-
-			serial_out(up, UART_LCR, 0);
-
-			up->port.uartclk = 921600*16;
-			up->port.type = PORT_NS16550A;
-			up->capabilities |= UART_NATSEMI;
-			return;
-		}
-	}
-
-	/*
-	 * No EFR.  Try to detect a TI16750, which only sets bit 5 of
-	 * the IIR when 64 byte FIFO mode is enabled when DLAB is set.
-	 * Try setting it with and without DLAB set.  Cheap clones
-	 * set bit 5 without DLAB set.
-	 */
-	serial_out(up, UART_LCR, 0);
-	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR7_64BYTE);
-	status1 = serial_in(up, UART_IIR) >> 5;
-	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
-	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
-	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR7_64BYTE);
-	status2 = serial_in(up, UART_IIR) >> 5;
-	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
-	serial_out(up, UART_LCR, 0);
-
-	DEBUG_AUTOCONF("iir1=%d iir2=%d ", status1, status2);
-
-	if (status1 == 6 && status2 == 7) {
-		up->port.type = PORT_16750;
-		up->capabilities |= UART_CAP_AFE | UART_CAP_SLEEP;
-		return;
-	}
-
-	/*
-	 * Try writing and reading the UART_IER_UUE bit (b6).
-	 * If it works, this is probably one of the Xscale platform's
-	 * internal UARTs.
-	 * We're going to explicitly set the UUE bit to 0 before
-	 * trying to write and read a 1 just to make sure it's not
-	 * already a 1 and maybe locked there before we even start start.
-	 */
-	iersave = serial_in(up, UART_IER);
-	serial_out(up, UART_IER, iersave & ~UART_IER_UUE);
-	if (!(serial_in(up, UART_IER) & UART_IER_UUE)) {
-		/*
-		 * OK it's in a known zero state, try writing and reading
-		 * without disturbing the current state of the other bits.
-		 */
-		serial_out(up, UART_IER, iersave | UART_IER_UUE);
-		if (serial_in(up, UART_IER) & UART_IER_UUE) {
-			/*
-			 * It's an Xscale.
-			 * We'll leave the UART_IER_UUE bit set to 1 (enabled).
-			 */
-			DEBUG_AUTOCONF("Xscale ");
-			up->port.type = PORT_XSCALE;
-			up->capabilities |= UART_CAP_UUE | UART_CAP_RTOIE;
-			return;
-		}
-	} else {
-		/*
-		 * If we got here we couldn't force the IER_UUE bit to 0.
-		 * Log it and continue.
-		 */
-		DEBUG_AUTOCONF("Couldn't force IER_UUE to 0 ");
-	}
-	serial_out(up, UART_IER, iersave);
-
-	/*
-	 * Exar uarts have EFR in a weird location
-	 */
-	if (up->port.flags & UPF_EXAR_EFR) {
-		DEBUG_AUTOCONF("Exar XR17D15x ");
-		up->port.type = PORT_XR17D15X;
-		up->capabilities |= UART_CAP_AFE | UART_CAP_EFR |
-				    UART_CAP_SLEEP;
-
-		return;
-	}
-
-	/*
-	 * We distinguish between 16550A and U6 16550A by counting
-	 * how many bytes are in the FIFO.
-	 */
-	if (up->port.type == PORT_16550A && size_fifo(up) == 64) {
-		up->port.type = PORT_U6_16550A;
-		up->capabilities |= UART_CAP_AFE;
-	}
-}
-
-/*
- * This routine is called by rs_init() to initialize a specific serial
- * port.  It determines what type of UART chip this serial port is
- * using: 8250, 16450, 16550, 16550A.  The important question is
- * whether or not this UART is a 16550A or not, since this will
- * determine whether or not we can use its FIFO features or not.
- */
-static void autoconfig(struct uart_8250_port *up)
-{
-	unsigned char status1, scratch, scratch2, scratch3;
-	unsigned char save_lcr, save_mcr;
-	struct uart_port *port = &up->port;
-	unsigned long flags;
-	unsigned int old_capabilities;
-
-	if (!port->iobase && !port->mapbase && !port->membase)
-		return;
-
-	DEBUG_AUTOCONF("ttyS%d: autoconf (0x%04lx, 0x%p): ",
-		       serial_index(port), port->iobase, port->membase);
-
-	/*
-	 * We really do need global IRQs disabled here - we're going to
-	 * be frobbing the chips IRQ enable register to see if it exists.
-	 */
-	spin_lock_irqsave(&port->lock, flags);
-
-	up->capabilities = 0;
-	up->bugs = 0;
-
-	if (!(port->flags & UPF_BUGGY_UART)) {
-		/*
-		 * Do a simple existence test first; if we fail this,
-		 * there's no point trying anything else.
-		 *
-		 * 0x80 is used as a nonsense port to prevent against
-		 * false positives due to ISA bus float.  The
-		 * assumption is that 0x80 is a non-existent port;
-		 * which should be safe since include/asm/io.h also
-		 * makes this assumption.
-		 *
-		 * Note: this is safe as long as MCR bit 4 is clear
-		 * and the device is in "PC" mode.
-		 */
-		scratch = serial_in(up, UART_IER);
-		serial_out(up, UART_IER, 0);
-#ifdef __i386__
-		outb(0xff, 0x080);
-#endif
-		/*
-		 * Mask out IER[7:4] bits for test as some UARTs (e.g. TL
-		 * 16C754B) allow only to modify them if an EFR bit is set.
-		 */
-		scratch2 = serial_in(up, UART_IER) & 0x0f;
-		serial_out(up, UART_IER, 0x0F);
-#ifdef __i386__
-		outb(0, 0x080);
-#endif
-		scratch3 = serial_in(up, UART_IER) & 0x0f;
-		serial_out(up, UART_IER, scratch);
-		if (scratch2 != 0 || scratch3 != 0x0F) {
-			/*
-			 * We failed; there's nothing here
-			 */
-			spin_unlock_irqrestore(&port->lock, flags);
-			DEBUG_AUTOCONF("IER test failed (%02x, %02x) ",
-				       scratch2, scratch3);
-			goto out;
-		}
-	}
-
-	save_mcr = serial_in(up, UART_MCR);
-	save_lcr = serial_in(up, UART_LCR);
-
-	/*
-	 * Check to see if a UART is really there.  Certain broken
-	 * internal modems based on the Rockwell chipset fail this
-	 * test, because they apparently don't implement the loopback
-	 * test mode.  So this test is skipped on the COM 1 through
-	 * COM 4 ports.  This *should* be safe, since no board
-	 * manufacturer would be stupid enough to design a board
-	 * that conflicts with COM 1-4 --- we hope!
-	 */
-	if (!(port->flags & UPF_SKIP_TEST)) {
-		serial_out(up, UART_MCR, UART_MCR_LOOP | 0x0A);
-		status1 = serial_in(up, UART_MSR) & 0xF0;
-		serial_out(up, UART_MCR, save_mcr);
-		if (status1 != 0x90) {
-			spin_unlock_irqrestore(&port->lock, flags);
-			DEBUG_AUTOCONF("LOOP test failed (%02x) ",
-				       status1);
-			goto out;
-		}
-	}
-
-	/*
-	 * We're pretty sure there's a port here.  Lets find out what
-	 * type of port it is.  The IIR top two bits allows us to find
-	 * out if it's 8250 or 16450, 16550, 16550A or later.  This
-	 * determines what we test for next.
-	 *
-	 * We also initialise the EFR (if any) to zero for later.  The
-	 * EFR occupies the same register location as the FCR and IIR.
-	 */
-	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
-	serial_out(up, UART_EFR, 0);
-	serial_out(up, UART_LCR, 0);
-
-	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
-	scratch = serial_in(up, UART_IIR) >> 6;
-
-	switch (scratch) {
-	case 0:
-		autoconfig_8250(up);
-		break;
-	case 1:
-		port->type = PORT_UNKNOWN;
-		break;
-	case 2:
-		port->type = PORT_16550;
-		break;
-	case 3:
-		autoconfig_16550a(up);
-		break;
-	}
-
-#ifdef CONFIG_SERIAL_8250_RSA
-	/*
-	 * Only probe for RSA ports if we got the region.
-	 */
-	if (port->type == PORT_16550A && up->probe & UART_PROBE_RSA &&
-	    __enable_rsa(up))
-		port->type = PORT_RSA;
-#endif
-
-	serial_out(up, UART_LCR, save_lcr);
-
-	port->fifosize = uart_config[up->port.type].fifo_size;
-	old_capabilities = up->capabilities;
-	up->capabilities = uart_config[port->type].flags;
-	up->tx_loadsz = uart_config[port->type].tx_loadsz;
-
-	if (port->type == PORT_UNKNOWN)
-		goto out_lock;
-
-	/*
-	 * Reset the UART.
-	 */
-#ifdef CONFIG_SERIAL_8250_RSA
-	if (port->type == PORT_RSA)
-		serial_out(up, UART_RSA_FRR, 0);
-#endif
-	serial_out(up, UART_MCR, save_mcr);
-	serial8250_clear_fifos(up);
-	serial_in(up, UART_RX);
-	if (up->capabilities & UART_CAP_UUE)
-		serial_out(up, UART_IER, UART_IER_UUE);
-	else
-		serial_out(up, UART_IER, 0);
-
-out_lock:
-	spin_unlock_irqrestore(&port->lock, flags);
-	if (up->capabilities != old_capabilities) {
-		printk(KERN_WARNING
-		       "ttyS%d: detected caps %08x should be %08x\n",
-		       serial_index(port), old_capabilities,
-		       up->capabilities);
-	}
-out:
-	DEBUG_AUTOCONF("iir=%d ", scratch);
-	DEBUG_AUTOCONF("type=%s\n", uart_config[port->type].name);
-}
-
-static void autoconfig_irq(struct uart_8250_port *up)
-{
-	struct uart_port *port = &up->port;
-	unsigned char save_mcr, save_ier;
-	unsigned char save_ICP = 0;
-	unsigned int ICP = 0;
-	unsigned long irqs;
-	int irq;
-
-	if (port->flags & UPF_FOURPORT) {
-		ICP = (port->iobase & 0xfe0) | 0x1f;
-		save_ICP = inb_p(ICP);
-		outb_p(0x80, ICP);
-		inb_p(ICP);
-	}
-
-	/* forget possible initially masked and pending IRQ */
-	probe_irq_off(probe_irq_on());
-	save_mcr = serial_in(up, UART_MCR);
-	save_ier = serial_in(up, UART_IER);
-	serial_out(up, UART_MCR, UART_MCR_OUT1 | UART_MCR_OUT2);
-
-	irqs = probe_irq_on();
-	serial_out(up, UART_MCR, 0);
-	udelay(10);
-	if (port->flags & UPF_FOURPORT) {
-		serial_out(up, UART_MCR,
-			    UART_MCR_DTR | UART_MCR_RTS);
-	} else {
-		serial_out(up, UART_MCR,
-			    UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2);
-	}
-	serial_out(up, UART_IER, 0x0f);	/* enable all intrs */
-	serial_in(up, UART_LSR);
-	serial_in(up, UART_RX);
-	serial_in(up, UART_IIR);
-	serial_in(up, UART_MSR);
-	serial_out(up, UART_TX, 0xFF);
-	udelay(20);
-	irq = probe_irq_off(irqs);
-
-	serial_out(up, UART_MCR, save_mcr);
-	serial_out(up, UART_IER, save_ier);
-
-	if (port->flags & UPF_FOURPORT)
-		outb_p(save_ICP, ICP);
-
-	port->irq = (irq > 0) ? irq : 0;
-}
-
-static inline void __stop_tx(struct uart_8250_port *p)
-{
-	if (p->ier & UART_IER_THRI) {
-		p->ier &= ~UART_IER_THRI;
-		serial_out(p, UART_IER, p->ier);
-		serial8250_rpm_put_tx(p);
-	}
-}
-
-static void serial8250_stop_tx(struct uart_port *port)
-{
-	struct uart_8250_port *up = up_to_u8250p(port);
-
-	serial8250_rpm_get(up);
-	__stop_tx(up);
-
-	/*
-	 * We really want to stop the transmitter from sending.
-	 */
-	if (port->type == PORT_16C950) {
-		up->acr |= UART_ACR_TXDIS;
-		serial_icr_write(up, UART_ACR, up->acr);
-	}
-	serial8250_rpm_put(up);
-}
-
-static void serial8250_start_tx(struct uart_port *port)
-{
-	struct uart_8250_port *up = up_to_u8250p(port);
-
-	serial8250_rpm_get_tx(up);
-
-	if (up->dma && !up->dma->tx_dma(up))
-		return;
-
-	if (!(up->ier & UART_IER_THRI)) {
-		up->ier |= UART_IER_THRI;
-		serial_port_out(port, UART_IER, up->ier);
-
-		if (up->bugs & UART_BUG_TXEN) {
-			unsigned char lsr;
-			lsr = serial_in(up, UART_LSR);
-			up->lsr_saved_flags |= lsr & LSR_SAVE_FLAGS;
-			if (lsr & UART_LSR_THRE)
-				serial8250_tx_chars(up);
-		}
-	}
-
-	/*
-	 * Re-enable the transmitter if we disabled it.
-	 */
-	if (port->type == PORT_16C950 && up->acr & UART_ACR_TXDIS) {
-		up->acr &= ~UART_ACR_TXDIS;
-		serial_icr_write(up, UART_ACR, up->acr);
-	}
-}
-
-static void serial8250_throttle(struct uart_port *port)
-{
-	port->throttle(port);
-}
-
-static void serial8250_unthrottle(struct uart_port *port)
-{
-	port->unthrottle(port);
-}
-
-static void serial8250_stop_rx(struct uart_port *port)
-{
-	struct uart_8250_port *up = up_to_u8250p(port);
-
-	serial8250_rpm_get(up);
-
-	up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
-	up->port.read_status_mask &= ~UART_LSR_DR;
-	serial_port_out(port, UART_IER, up->ier);
-
-	serial8250_rpm_put(up);
-}
-
-static void serial8250_disable_ms(struct uart_port *port)
-{
-	struct uart_8250_port *up =
-		container_of(port, struct uart_8250_port, port);
-
-	/* no MSR capabilities */
-	if (up->bugs & UART_BUG_NOMSR)
-		return;
-
-	up->ier &= ~UART_IER_MSI;
-	serial_port_out(port, UART_IER, up->ier);
-}
-
-static void serial8250_enable_ms(struct uart_port *port)
-{
-	struct uart_8250_port *up = up_to_u8250p(port);
-
-	/* no MSR capabilities */
-	if (up->bugs & UART_BUG_NOMSR)
-		return;
-
-	up->ier |= UART_IER_MSI;
-
-	serial8250_rpm_get(up);
-	serial_port_out(port, UART_IER, up->ier);
-	serial8250_rpm_put(up);
-}
-
-/*
- * serial8250_rx_chars: processes according to the passed in LSR
- * value, and returns the remaining LSR bits not handled
- * by this Rx routine.
- */
-unsigned char
-serial8250_rx_chars(struct uart_8250_port *up, unsigned char lsr)
-{
-	struct uart_port *port = &up->port;
-	unsigned char ch;
-	int max_count = 256;
-	char flag;
-
-	do {
-		if (likely(lsr & UART_LSR_DR))
-			ch = serial_in(up, UART_RX);
-		else
-			/*
-			 * Intel 82571 has a Serial Over Lan device that will
-			 * set UART_LSR_BI without setting UART_LSR_DR when
-			 * it receives a break. To avoid reading from the
-			 * receive buffer without UART_LSR_DR bit set, we
-			 * just force the read character to be 0
-			 */
-			ch = 0;
-
-		flag = TTY_NORMAL;
-		port->icount.rx++;
-
-		lsr |= up->lsr_saved_flags;
-		up->lsr_saved_flags = 0;
-
-		if (unlikely(lsr & UART_LSR_BRK_ERROR_BITS)) {
-			if (lsr & UART_LSR_BI) {
-				lsr &= ~(UART_LSR_FE | UART_LSR_PE);
-				port->icount.brk++;
-				/*
-				 * We do the SysRQ and SAK checking
-				 * here because otherwise the break
-				 * may get masked by ignore_status_mask
-				 * or read_status_mask.
-				 */
-				if (uart_handle_break(port))
-					goto ignore_char;
-			} else if (lsr & UART_LSR_PE)
-				port->icount.parity++;
-			else if (lsr & UART_LSR_FE)
-				port->icount.frame++;
-			if (lsr & UART_LSR_OE)
-				port->icount.overrun++;
-
-			/*
-			 * Mask off conditions which should be ignored.
-			 */
-			lsr &= port->read_status_mask;
-
-			if (lsr & UART_LSR_BI) {
-				DEBUG_INTR("handling break....");
-				flag = TTY_BREAK;
-			} else if (lsr & UART_LSR_PE)
-				flag = TTY_PARITY;
-			else if (lsr & UART_LSR_FE)
-				flag = TTY_FRAME;
-		}
-		if (uart_handle_sysrq_char(port, ch))
-			goto ignore_char;
-
-		uart_insert_char(port, lsr, UART_LSR_OE, ch, flag);
-
-ignore_char:
-		lsr = serial_in(up, UART_LSR);
-	} while ((lsr & (UART_LSR_DR | UART_LSR_BI)) && (--max_count > 0));
-	spin_unlock(&port->lock);
-	tty_flip_buffer_push(&port->state->port);
-	spin_lock(&port->lock);
-	return lsr;
-}
-EXPORT_SYMBOL_GPL(serial8250_rx_chars);
-
-void serial8250_tx_chars(struct uart_8250_port *up)
-{
-	struct uart_port *port = &up->port;
-	struct circ_buf *xmit = &port->state->xmit;
-	int count;
-
-	if (port->x_char) {
-		serial_out(up, UART_TX, port->x_char);
-		port->icount.tx++;
-		port->x_char = 0;
-		return;
-	}
-	if (uart_tx_stopped(port)) {
-		serial8250_stop_tx(port);
-		return;
-	}
-	if (uart_circ_empty(xmit)) {
-		__stop_tx(up);
-		return;
-	}
-
-	count = up->tx_loadsz;
-	do {
-		serial_out(up, UART_TX, xmit->buf[xmit->tail]);
-		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
-		port->icount.tx++;
-		if (uart_circ_empty(xmit))
-			break;
-		if (up->capabilities & UART_CAP_HFIFO) {
-			if ((serial_port_in(port, UART_LSR) & BOTH_EMPTY) !=
-			    BOTH_EMPTY)
-				break;
-		}
-	} while (--count > 0);
-
-	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
-		uart_write_wakeup(port);
-
-	DEBUG_INTR("THRE...");
-
-	/*
-	 * With RPM enabled, we have to wait until the FIFO is empty before the
-	 * HW can go idle. So we get here once again with empty FIFO and disable
-	 * the interrupt and RPM in __stop_tx()
-	 */
-	if (uart_circ_empty(xmit) && !(up->capabilities & UART_CAP_RPM))
-		__stop_tx(up);
-}
-EXPORT_SYMBOL_GPL(serial8250_tx_chars);
-
-/* Caller holds uart port lock */
-unsigned int serial8250_modem_status(struct uart_8250_port *up)
-{
-	struct uart_port *port = &up->port;
-	unsigned int status = serial_in(up, UART_MSR);
-
-	status |= up->msr_saved_flags;
-	up->msr_saved_flags = 0;
-	if (status & UART_MSR_ANY_DELTA && up->ier & UART_IER_MSI &&
-	    port->state != NULL) {
-		if (status & UART_MSR_TERI)
-			port->icount.rng++;
-		if (status & UART_MSR_DDSR)
-			port->icount.dsr++;
-		if (status & UART_MSR_DDCD)
-			uart_handle_dcd_change(port, status & UART_MSR_DCD);
-		if (status & UART_MSR_DCTS)
-			uart_handle_cts_change(port, status & UART_MSR_CTS);
-
-		wake_up_interruptible(&port->state->port.delta_msr_wait);
-	}
-
-	return status;
-}
-EXPORT_SYMBOL_GPL(serial8250_modem_status);
-
-/*
- * This handles the interrupt from one port.
- */
-int serial8250_handle_irq(struct uart_port *port, unsigned int iir)
-{
-	unsigned char status;
-	unsigned long flags;
-	struct uart_8250_port *up = up_to_u8250p(port);
-	int dma_err = 0;
-
-	if (iir & UART_IIR_NO_INT)
-		return 0;
-
-	spin_lock_irqsave(&port->lock, flags);
-
-	status = serial_port_in(port, UART_LSR);
-
-	DEBUG_INTR("status = %x...", status);
-
-	if (status & (UART_LSR_DR | UART_LSR_BI)) {
-		if (up->dma)
-			dma_err = up->dma->rx_dma(up, iir);
-
-		if (!up->dma || dma_err)
-			status = serial8250_rx_chars(up, status);
-	}
-	serial8250_modem_status(up);
-	if ((!up->dma || (up->dma && up->dma->tx_err)) &&
-	    (status & UART_LSR_THRE))
-		serial8250_tx_chars(up);
-
-	spin_unlock_irqrestore(&port->lock, flags);
-	return 1;
-}
-EXPORT_SYMBOL_GPL(serial8250_handle_irq);
-
-static int serial8250_default_handle_irq(struct uart_port *port)
-{
-	struct uart_8250_port *up = up_to_u8250p(port);
-	unsigned int iir;
-	int ret;
-
-	serial8250_rpm_get(up);
-
-	iir = serial_port_in(port, UART_IIR);
-	ret = serial8250_handle_irq(port, iir);
-
-	serial8250_rpm_put(up);
-	return ret;
-}
-
-/*
- * These Exar UARTs have an extra interrupt indicator that could
- * fire for a few unimplemented interrupts.  One of which is a
- * wakeup event when coming out of sleep.  Put this here just
- * to be on the safe side that these interrupts don't go unhandled.
- */
-static int exar_handle_irq(struct uart_port *port)
-{
-	unsigned char int0, int1, int2, int3;
-	unsigned int iir = serial_port_in(port, UART_IIR);
-	int ret;
-
-	ret = serial8250_handle_irq(port, iir);
-
-	if ((port->type == PORT_XR17V35X) ||
-	   (port->type == PORT_XR17D15X)) {
-		int0 = serial_port_in(port, 0x80);
-		int1 = serial_port_in(port, 0x81);
-		int2 = serial_port_in(port, 0x82);
-		int3 = serial_port_in(port, 0x83);
-	}
-
-	return ret;
-}
-
-/*
- * This is the serial driver's interrupt routine.
- *
- * Arjan thinks the old way was overly complex, so it got simplified.
- * Alan disagrees, saying that need the complexity to handle the weird
- * nature of ISA shared interrupts.  (This is a special exception.)
- *
- * In order to handle ISA shared interrupts properly, we need to check
- * that all ports have been serviced, and therefore the ISA interrupt
- * line has been de-asserted.
- *
- * This means we need to loop through all ports. checking that they
- * don't have an interrupt pending.
- */
-static irqreturn_t serial8250_interrupt(int irq, void *dev_id)
-{
-	struct irq_info *i = dev_id;
-	struct list_head *l, *end = NULL;
-	int pass_counter = 0, handled = 0;
-
-	DEBUG_INTR("serial8250_interrupt(%d)...", irq);
-
-	spin_lock(&i->lock);
-
-	l = i->head;
-	do {
-		struct uart_8250_port *up;
-		struct uart_port *port;
-
-		up = list_entry(l, struct uart_8250_port, list);
-		port = &up->port;
-
-		if (port->handle_irq(port)) {
-			handled = 1;
-			end = NULL;
-		} else if (end == NULL)
-			end = l;
-
-		l = l->next;
-
-		if (l == i->head && pass_counter++ > PASS_LIMIT) {
-			/* If we hit this, we're dead. */
-			printk_ratelimited(KERN_ERR
-				"serial8250: too much work for irq%d\n", irq);
-			break;
-		}
-	} while (l != end);
-
-	spin_unlock(&i->lock);
-
-	DEBUG_INTR("end.\n");
-
-	return IRQ_RETVAL(handled);
-}
-
-/*
- * To support ISA shared interrupts, we need to have one interrupt
- * handler that ensures that the IRQ line has been deasserted
- * before returning.  Failing to do this will result in the IRQ
- * line being stuck active, and, since ISA irqs are edge triggered,
- * no more IRQs will be seen.
- */
-static void serial_do_unlink(struct irq_info *i, struct uart_8250_port *up)
-{
-	spin_lock_irq(&i->lock);
-
-	if (!list_empty(i->head)) {
-		if (i->head == &up->list)
-			i->head = i->head->next;
-		list_del(&up->list);
-	} else {
-		BUG_ON(i->head != &up->list);
-		i->head = NULL;
-	}
-	spin_unlock_irq(&i->lock);
-	/* List empty so throw away the hash node */
-	if (i->head == NULL) {
-		hlist_del(&i->node);
-		kfree(i);
-	}
-}
-
-static int serial_link_irq_chain(struct uart_8250_port *up)
-{
-	struct hlist_head *h;
-	struct hlist_node *n;
-	struct irq_info *i;
-	int ret, irq_flags = up->port.flags & UPF_SHARE_IRQ ? IRQF_SHARED : 0;
-
-	mutex_lock(&hash_mutex);
-
-	h = &irq_lists[up->port.irq % NR_IRQ_HASH];
-
-	hlist_for_each(n, h) {
-		i = hlist_entry(n, struct irq_info, node);
-		if (i->irq == up->port.irq)
-			break;
-	}
-
-	if (n == NULL) {
-		i = kzalloc(sizeof(struct irq_info), GFP_KERNEL);
-		if (i == NULL) {
-			mutex_unlock(&hash_mutex);
-			return -ENOMEM;
-		}
-		spin_lock_init(&i->lock);
-		i->irq = up->port.irq;
-		hlist_add_head(&i->node, h);
-	}
-	mutex_unlock(&hash_mutex);
-
-	spin_lock_irq(&i->lock);
-
-	if (i->head) {
-		list_add(&up->list, i->head);
-		spin_unlock_irq(&i->lock);
-
-		ret = 0;
-	} else {
-		INIT_LIST_HEAD(&up->list);
-		i->head = &up->list;
-		spin_unlock_irq(&i->lock);
-		irq_flags |= up->port.irqflags;
-		ret = request_irq(up->port.irq, serial8250_interrupt,
-				  irq_flags, "serial", i);
-		if (ret < 0)
-			serial_do_unlink(i, up);
-	}
-
-	return ret;
-}
-
-static void serial_unlink_irq_chain(struct uart_8250_port *up)
-{
-	/*
-	 * yes, some broken gcc emit "warning: 'i' may be used uninitialized"
-	 * but no, we are not going to take a patch that assigns NULL below.
-	 */
-	struct irq_info *i;
-	struct hlist_node *n;
-	struct hlist_head *h;
-
-	mutex_lock(&hash_mutex);
-
-	h = &irq_lists[up->port.irq % NR_IRQ_HASH];
-
-	hlist_for_each(n, h) {
-		i = hlist_entry(n, struct irq_info, node);
-		if (i->irq == up->port.irq)
-			break;
-	}
-
-	BUG_ON(n == NULL);
-	BUG_ON(i->head == NULL);
-
-	if (list_empty(i->head))
-		free_irq(up->port.irq, i);
-
-	serial_do_unlink(i, up);
-	mutex_unlock(&hash_mutex);
-}
-
-/*
- * This function is used to handle ports that do not have an
- * interrupt.  This doesn't work very well for 16450's, but gives
- * barely passable results for a 16550A.  (Although at the expense
- * of much CPU overhead).
- */
-static void serial8250_timeout(unsigned long data)
-{
-	struct uart_8250_port *up = (struct uart_8250_port *)data;
-
-	up->port.handle_irq(&up->port);
-	mod_timer(&up->timer, jiffies + uart_poll_timeout(&up->port));
-}
-
-static void serial8250_backup_timeout(unsigned long data)
-{
-	struct uart_8250_port *up = (struct uart_8250_port *)data;
-	unsigned int iir, ier = 0, lsr;
-	unsigned long flags;
-
-	spin_lock_irqsave(&up->port.lock, flags);
-
-	/*
-	 * Must disable interrupts or else we risk racing with the interrupt
-	 * based handler.
-	 */
-	if (up->port.irq) {
-		ier = serial_in(up, UART_IER);
-		serial_out(up, UART_IER, 0);
-	}
-
-	iir = serial_in(up, UART_IIR);
-
-	/*
-	 * This should be a safe test for anyone who doesn't trust the
-	 * IIR bits on their UART, but it's specifically designed for
-	 * the "Diva" UART used on the management processor on many HP
-	 * ia64 and parisc boxes.
-	 */
-	lsr = serial_in(up, UART_LSR);
-	up->lsr_saved_flags |= lsr & LSR_SAVE_FLAGS;
-	if ((iir & UART_IIR_NO_INT) && (up->ier & UART_IER_THRI) &&
-	    (!uart_circ_empty(&up->port.state->xmit) || up->port.x_char) &&
-	    (lsr & UART_LSR_THRE)) {
-		iir &= ~(UART_IIR_ID | UART_IIR_NO_INT);
-		iir |= UART_IIR_THRI;
-	}
-
-	if (!(iir & UART_IIR_NO_INT))
-		serial8250_tx_chars(up);
-
-	if (up->port.irq)
-		serial_out(up, UART_IER, ier);
-
-	spin_unlock_irqrestore(&up->port.lock, flags);
-
-	/* Standard timer interval plus 0.2s to keep the port running */
-	mod_timer(&up->timer,
-		jiffies + uart_poll_timeout(&up->port) + HZ / 5);
-}
-
-static int univ8250_setup_irq(struct uart_8250_port *up)
-{
-	struct uart_port *port = &up->port;
-	int retval = 0;
-
-	/*
-	 * The above check will only give an accurate result the first time
-	 * the port is opened so this value needs to be preserved.
-	 */
-	if (up->bugs & UART_BUG_THRE) {
-		pr_debug("ttyS%d - using backup timer\n", serial_index(port));
-
-		up->timer.function = serial8250_backup_timeout;
-		up->timer.data = (unsigned long)up;
-		mod_timer(&up->timer, jiffies +
-			  uart_poll_timeout(port) + HZ / 5);
-	}
-
-	/*
-	 * If the "interrupt" for this port doesn't correspond with any
-	 * hardware interrupt, we use a timer-based system.  The original
-	 * driver used to do this with IRQ0.
-	 */
-	if (!port->irq) {
-		up->timer.data = (unsigned long)up;
-		mod_timer(&up->timer, jiffies + uart_poll_timeout(port));
-	} else
-		retval = serial_link_irq_chain(up);
-
-	return retval;
-}
-
-static void univ8250_release_irq(struct uart_8250_port *up)
-{
-	struct uart_port *port = &up->port;
-
-	del_timer_sync(&up->timer);
-	up->timer.function = serial8250_timeout;
-	if (port->irq)
-		serial_unlink_irq_chain(up);
-}
-
-static unsigned int serial8250_tx_empty(struct uart_port *port)
-{
-	struct uart_8250_port *up = up_to_u8250p(port);
-	unsigned long flags;
-	unsigned int lsr;
-
-	serial8250_rpm_get(up);
-
-	spin_lock_irqsave(&port->lock, flags);
-	lsr = serial_port_in(port, UART_LSR);
-	up->lsr_saved_flags |= lsr & LSR_SAVE_FLAGS;
-	spin_unlock_irqrestore(&port->lock, flags);
-
-	serial8250_rpm_put(up);
-
-	return (lsr & BOTH_EMPTY) == BOTH_EMPTY ? TIOCSER_TEMT : 0;
-}
-
-static unsigned int serial8250_get_mctrl(struct uart_port *port)
-{
-	struct uart_8250_port *up = up_to_u8250p(port);
-	unsigned int status;
-	unsigned int ret;
-
-	serial8250_rpm_get(up);
-	status = serial8250_modem_status(up);
-	serial8250_rpm_put(up);
-
-	ret = 0;
-	if (status & UART_MSR_DCD)
-		ret |= TIOCM_CAR;
-	if (status & UART_MSR_RI)
-		ret |= TIOCM_RNG;
-	if (status & UART_MSR_DSR)
-		ret |= TIOCM_DSR;
-	if (status & UART_MSR_CTS)
-		ret |= TIOCM_CTS;
-	return ret;
-}
-
-void serial8250_do_set_mctrl(struct uart_port *port, unsigned int mctrl)
-{
-	struct uart_8250_port *up = up_to_u8250p(port);
-	unsigned char mcr = 0;
-
-	if (mctrl & TIOCM_RTS)
-		mcr |= UART_MCR_RTS;
-	if (mctrl & TIOCM_DTR)
-		mcr |= UART_MCR_DTR;
-	if (mctrl & TIOCM_OUT1)
-		mcr |= UART_MCR_OUT1;
-	if (mctrl & TIOCM_OUT2)
-		mcr |= UART_MCR_OUT2;
-	if (mctrl & TIOCM_LOOP)
-		mcr |= UART_MCR_LOOP;
-
-	mcr = (mcr & up->mcr_mask) | up->mcr_force | up->mcr;
-
-	serial_port_out(port, UART_MCR, mcr);
-}
-EXPORT_SYMBOL_GPL(serial8250_do_set_mctrl);
-
-static void serial8250_set_mctrl(struct uart_port *port, unsigned int mctrl)
-{
-	if (port->set_mctrl)
-		port->set_mctrl(port, mctrl);
-	else
-		serial8250_do_set_mctrl(port, mctrl);
-}
-
-static void serial8250_break_ctl(struct uart_port *port, int break_state)
-{
-	struct uart_8250_port *up = up_to_u8250p(port);
-	unsigned long flags;
-
-	serial8250_rpm_get(up);
-	spin_lock_irqsave(&port->lock, flags);
-	if (break_state == -1)
-		up->lcr |= UART_LCR_SBC;
-	else
-		up->lcr &= ~UART_LCR_SBC;
-	serial_port_out(port, UART_LCR, up->lcr);
-	spin_unlock_irqrestore(&port->lock, flags);
-	serial8250_rpm_put(up);
-}
-
-/*
- *	Wait for transmitter & holding register to empty
- */
-static void wait_for_xmitr(struct uart_8250_port *up, int bits)
-{
-	unsigned int status, tmout = 10000;
-
-	/* Wait up to 10ms for the character(s) to be sent. */
-	for (;;) {
-		status = serial_in(up, UART_LSR);
-
-		up->lsr_saved_flags |= status & LSR_SAVE_FLAGS;
-
-		if ((status & bits) == bits)
-			break;
-		if (--tmout == 0)
-			break;
-		udelay(1);
-	}
-
-	/* Wait up to 1s for flow control if necessary */
-	if (up->port.flags & UPF_CONS_FLOW) {
-		unsigned int tmout;
-		for (tmout = 1000000; tmout; tmout--) {
-			unsigned int msr = serial_in(up, UART_MSR);
-			up->msr_saved_flags |= msr & MSR_SAVE_FLAGS;
-			if (msr & UART_MSR_CTS)
-				break;
-			udelay(1);
-			touch_nmi_watchdog();
-		}
-	}
-}
-
-#ifdef CONFIG_CONSOLE_POLL
-/*
- * Console polling routines for writing and reading from the uart while
- * in an interrupt or debug context.
- */
-
-static int serial8250_get_poll_char(struct uart_port *port)
-{
-	struct uart_8250_port *up = up_to_u8250p(port);
-	unsigned char lsr;
-	int status;
-
-	serial8250_rpm_get(up);
-
-	lsr = serial_port_in(port, UART_LSR);
-
-	if (!(lsr & UART_LSR_DR)) {
-		status = NO_POLL_CHAR;
-		goto out;
-	}
-
-	status = serial_port_in(port, UART_RX);
-out:
-	serial8250_rpm_put(up);
-	return status;
-}
-
-
-static void serial8250_put_poll_char(struct uart_port *port,
-			 unsigned char c)
-{
-	unsigned int ier;
-	struct uart_8250_port *up = up_to_u8250p(port);
-
-	serial8250_rpm_get(up);
-	/*
-	 *	First save the IER then disable the interrupts
-	 */
-	ier = serial_port_in(port, UART_IER);
-	if (up->capabilities & UART_CAP_UUE)
-		serial_port_out(port, UART_IER, UART_IER_UUE);
-	else
-		serial_port_out(port, UART_IER, 0);
-
-	wait_for_xmitr(up, BOTH_EMPTY);
-	/*
-	 *	Send the character out.
-	 */
-	serial_port_out(port, UART_TX, c);
-
-	/*
-	 *	Finally, wait for transmitter to become empty
-	 *	and restore the IER
-	 */
-	wait_for_xmitr(up, BOTH_EMPTY);
-	serial_port_out(port, UART_IER, ier);
-	serial8250_rpm_put(up);
-}
-
-#endif /* CONFIG_CONSOLE_POLL */
-
-int serial8250_do_startup(struct uart_port *port)
-{
-	struct uart_8250_port *up = up_to_u8250p(port);
-	unsigned long flags;
-	unsigned char lsr, iir;
-	int retval;
-
-	if (port->type == PORT_8250_CIR)
-		return -ENODEV;
-
-	if (!port->fifosize)
-		port->fifosize = uart_config[port->type].fifo_size;
-	if (!up->tx_loadsz)
-		up->tx_loadsz = uart_config[port->type].tx_loadsz;
-	if (!up->capabilities)
-		up->capabilities = uart_config[port->type].flags;
-	up->mcr = 0;
-
-	if (port->iotype != up->cur_iotype)
-		set_io_from_upio(port);
-
-	serial8250_rpm_get(up);
-	if (port->type == PORT_16C950) {
-		/* Wake up and initialize UART */
-		up->acr = 0;
-		serial_port_out(port, UART_LCR, UART_LCR_CONF_MODE_B);
-		serial_port_out(port, UART_EFR, UART_EFR_ECB);
-		serial_port_out(port, UART_IER, 0);
-		serial_port_out(port, UART_LCR, 0);
-		serial_icr_write(up, UART_CSR, 0); /* Reset the UART */
-		serial_port_out(port, UART_LCR, UART_LCR_CONF_MODE_B);
-		serial_port_out(port, UART_EFR, UART_EFR_ECB);
-		serial_port_out(port, UART_LCR, 0);
-	}
-
-#ifdef CONFIG_SERIAL_8250_RSA
-	/*
-	 * If this is an RSA port, see if we can kick it up to the
-	 * higher speed clock.
-	 */
-	enable_rsa(up);
-#endif
-	/*
-	 * Clear the FIFO buffers and disable them.
-	 * (they will be reenabled in set_termios())
-	 */
-	serial8250_clear_fifos(up);
-
-	/*
-	 * Clear the interrupt registers.
-	 */
-	serial_port_in(port, UART_LSR);
-	serial_port_in(port, UART_RX);
-	serial_port_in(port, UART_IIR);
-	serial_port_in(port, UART_MSR);
-
-	/*
-	 * At this point, there's no way the LSR could still be 0xff;
-	 * if it is, then bail out, because there's likely no UART
-	 * here.
-	 */
-	if (!(port->flags & UPF_BUGGY_UART) &&
-	    (serial_port_in(port, UART_LSR) == 0xff)) {
-		printk_ratelimited(KERN_INFO "ttyS%d: LSR safety check engaged!\n",
-				   serial_index(port));
-		retval = -ENODEV;
-		goto out;
-	}
-
-	/*
-	 * For a XR16C850, we need to set the trigger levels
-	 */
-	if (port->type == PORT_16850) {
-		unsigned char fctr;
-
-		serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
-
-		fctr = serial_in(up, UART_FCTR) & ~(UART_FCTR_RX|UART_FCTR_TX);
-		serial_port_out(port, UART_FCTR,
-				fctr | UART_FCTR_TRGD | UART_FCTR_RX);
-		serial_port_out(port, UART_TRG, UART_TRG_96);
-		serial_port_out(port, UART_FCTR,
-				fctr | UART_FCTR_TRGD | UART_FCTR_TX);
-		serial_port_out(port, UART_TRG, UART_TRG_96);
-
-		serial_port_out(port, UART_LCR, 0);
-	}
-
-	if (port->irq) {
-		unsigned char iir1;
-		/*
-		 * Test for UARTs that do not reassert THRE when the
-		 * transmitter is idle and the interrupt has already
-		 * been cleared.  Real 16550s should always reassert
-		 * this interrupt whenever the transmitter is idle and
-		 * the interrupt is enabled.  Delays are necessary to
-		 * allow register changes to become visible.
-		 */
-		spin_lock_irqsave(&port->lock, flags);
-		if (up->port.irqflags & IRQF_SHARED)
-			disable_irq_nosync(port->irq);
-
-		wait_for_xmitr(up, UART_LSR_THRE);
-		serial_port_out_sync(port, UART_IER, UART_IER_THRI);
-		udelay(1); /* allow THRE to set */
-		iir1 = serial_port_in(port, UART_IIR);
-		serial_port_out(port, UART_IER, 0);
-		serial_port_out_sync(port, UART_IER, UART_IER_THRI);
-		udelay(1); /* allow a working UART time to re-assert THRE */
-		iir = serial_port_in(port, UART_IIR);
-		serial_port_out(port, UART_IER, 0);
-
-		if (port->irqflags & IRQF_SHARED)
-			enable_irq(port->irq);
-		spin_unlock_irqrestore(&port->lock, flags);
-
-		/*
-		 * If the interrupt is not reasserted, or we otherwise
-		 * don't trust the iir, setup a timer to kick the UART
-		 * on a regular basis.
-		 */
-		if ((!(iir1 & UART_IIR_NO_INT) && (iir & UART_IIR_NO_INT)) ||
-		    up->port.flags & UPF_BUG_THRE) {
-			up->bugs |= UART_BUG_THRE;
-		}
-	}
-
-	retval = up->ops->setup_irq(up);
-	if (retval)
-		goto out;
-
-	/*
-	 * Now, initialize the UART
-	 */
-	serial_port_out(port, UART_LCR, UART_LCR_WLEN8);
-
-	spin_lock_irqsave(&port->lock, flags);
-	if (up->port.flags & UPF_FOURPORT) {
-		if (!up->port.irq)
-			up->port.mctrl |= TIOCM_OUT1;
-	} else
-		/*
-		 * Most PC uarts need OUT2 raised to enable interrupts.
-		 */
-		if (port->irq)
-			up->port.mctrl |= TIOCM_OUT2;
-
-	serial8250_set_mctrl(port, port->mctrl);
-
-	/* Serial over Lan (SoL) hack:
-	   Intel 8257x Gigabit ethernet chips have a
-	   16550 emulation, to be used for Serial Over Lan.
-	   Those chips take a longer time than a normal
-	   serial device to signalize that a transmission
-	   data was queued. Due to that, the above test generally
-	   fails. One solution would be to delay the reading of
-	   iir. However, this is not reliable, since the timeout
-	   is variable. So, let's just don't test if we receive
-	   TX irq. This way, we'll never enable UART_BUG_TXEN.
-	 */
-	if (up->port.flags & UPF_NO_TXEN_TEST)
-		goto dont_test_tx_en;
-
-	/*
-	 * Do a quick test to see if we receive an
-	 * interrupt when we enable the TX irq.
-	 */
-	serial_port_out(port, UART_IER, UART_IER_THRI);
-	lsr = serial_port_in(port, UART_LSR);
-	iir = serial_port_in(port, UART_IIR);
-	serial_port_out(port, UART_IER, 0);
-
-	if (lsr & UART_LSR_TEMT && iir & UART_IIR_NO_INT) {
-		if (!(up->bugs & UART_BUG_TXEN)) {
-			up->bugs |= UART_BUG_TXEN;
-			pr_debug("ttyS%d - enabling bad tx status workarounds\n",
-				 serial_index(port));
-		}
-	} else {
-		up->bugs &= ~UART_BUG_TXEN;
-	}
-
-dont_test_tx_en:
-	spin_unlock_irqrestore(&port->lock, flags);
-
-	/*
-	 * Clear the interrupt registers again for luck, and clear the
-	 * saved flags to avoid getting false values from polling
-	 * routines or the previous session.
-	 */
-	serial_port_in(port, UART_LSR);
-	serial_port_in(port, UART_RX);
-	serial_port_in(port, UART_IIR);
-	serial_port_in(port, UART_MSR);
-	up->lsr_saved_flags = 0;
-	up->msr_saved_flags = 0;
-
-	/*
-	 * Request DMA channels for both RX and TX.
-	 */
-	if (up->dma) {
-		retval = serial8250_request_dma(up);
-		if (retval) {
-			pr_warn_ratelimited("ttyS%d - failed to request DMA\n",
-					    serial_index(port));
-			up->dma = NULL;
-		}
-	}
-
-	/*
-	 * Finally, enable interrupts.  Note: Modem status interrupts
-	 * are set via set_termios(), which will be occurring imminently
-	 * anyway, so we don't enable them here.
-	 */
-	up->ier = UART_IER_RLSI | UART_IER_RDI;
-	serial_port_out(port, UART_IER, up->ier);
-
-	if (port->flags & UPF_FOURPORT) {
-		unsigned int icp;
-		/*
-		 * Enable interrupts on the AST Fourport board
-		 */
-		icp = (port->iobase & 0xfe0) | 0x01f;
-		outb_p(0x80, icp);
-		inb_p(icp);
-	}
-	retval = 0;
-out:
-	serial8250_rpm_put(up);
-	return retval;
-}
-EXPORT_SYMBOL_GPL(serial8250_do_startup);
-
-static int serial8250_startup(struct uart_port *port)
-{
-	if (port->startup)
-		return port->startup(port);
-	return serial8250_do_startup(port);
-}
-
-void serial8250_do_shutdown(struct uart_port *port)
-{
-	struct uart_8250_port *up = up_to_u8250p(port);
-	unsigned long flags;
-
-	serial8250_rpm_get(up);
-	/*
-	 * Disable interrupts from this port
-	 */
-	up->ier = 0;
-	serial_port_out(port, UART_IER, 0);
-
-	if (up->dma)
-		serial8250_release_dma(up);
-
-	spin_lock_irqsave(&port->lock, flags);
-	if (port->flags & UPF_FOURPORT) {
-		/* reset interrupts on the AST Fourport board */
-		inb((port->iobase & 0xfe0) | 0x1f);
-		port->mctrl |= TIOCM_OUT1;
-	} else
-		port->mctrl &= ~TIOCM_OUT2;
-
-	serial8250_set_mctrl(port, port->mctrl);
-	spin_unlock_irqrestore(&port->lock, flags);
-
-	/*
-	 * Disable break condition and FIFOs
-	 */
-	serial_port_out(port, UART_LCR,
-			serial_port_in(port, UART_LCR) & ~UART_LCR_SBC);
-	serial8250_clear_fifos(up);
-
-#ifdef CONFIG_SERIAL_8250_RSA
-	/*
-	 * Reset the RSA board back to 115kbps compat mode.
-	 */
-	disable_rsa(up);
-#endif
-
-	/*
-	 * Read data port to reset things, and then unlink from
-	 * the IRQ chain.
-	 */
-	serial_port_in(port, UART_RX);
-	serial8250_rpm_put(up);
-
-	up->ops->release_irq(up);
-}
-EXPORT_SYMBOL_GPL(serial8250_do_shutdown);
-
-static void serial8250_shutdown(struct uart_port *port)
-{
-	if (port->shutdown)
-		port->shutdown(port);
-	else
-		serial8250_do_shutdown(port);
-}
-
-/*
- * XR17V35x UARTs have an extra fractional divisor register (DLD)
- * Calculate divisor with extra 4-bit fractional portion
- */
-static unsigned int xr17v35x_get_divisor(struct uart_8250_port *up,
-					 unsigned int baud,
-					 unsigned int *frac)
-{
-	struct uart_port *port = &up->port;
-	unsigned int quot_16;
-
-	quot_16 = DIV_ROUND_CLOSEST(port->uartclk, baud);
-	*frac = quot_16 & 0x0f;
-
-	return quot_16 >> 4;
-}
-
-static unsigned int serial8250_get_divisor(struct uart_8250_port *up,
-					   unsigned int baud,
-					   unsigned int *frac)
-{
-	struct uart_port *port = &up->port;
-	unsigned int quot;
-
-	/*
-	 * Handle magic divisors for baud rates above baud_base on
-	 * SMSC SuperIO chips.
-	 *
-	 */
-	if ((port->flags & UPF_MAGIC_MULTIPLIER) &&
-	    baud == (port->uartclk/4))
-		quot = 0x8001;
-	else if ((port->flags & UPF_MAGIC_MULTIPLIER) &&
-		 baud == (port->uartclk/8))
-		quot = 0x8002;
-	else if (up->port.type == PORT_XR17V35X)
-		quot = xr17v35x_get_divisor(up, baud, frac);
-	else
-		quot = uart_get_divisor(port, baud);
-
-	/*
-	 * Oxford Semi 952 rev B workaround
-	 */
-	if (up->bugs & UART_BUG_QUOT && (quot & 0xff) == 0)
-		quot++;
-
-	return quot;
-}
-
-static unsigned char serial8250_compute_lcr(struct uart_8250_port *up,
-					    tcflag_t c_cflag)
-{
-	unsigned char cval;
-
-	switch (c_cflag & CSIZE) {
-	case CS5:
-		cval = UART_LCR_WLEN5;
-		break;
-	case CS6:
-		cval = UART_LCR_WLEN6;
-		break;
-	case CS7:
-		cval = UART_LCR_WLEN7;
-		break;
-	default:
-	case CS8:
-		cval = UART_LCR_WLEN8;
-		break;
-	}
-
-	if (c_cflag & CSTOPB)
-		cval |= UART_LCR_STOP;
-	if (c_cflag & PARENB) {
-		cval |= UART_LCR_PARITY;
-		if (up->bugs & UART_BUG_PARITY)
-			up->fifo_bug = true;
-	}
-	if (!(c_cflag & PARODD))
-		cval |= UART_LCR_EPAR;
-#ifdef CMSPAR
-	if (c_cflag & CMSPAR)
-		cval |= UART_LCR_SPAR;
-#endif
-
-	return cval;
-}
-
-static void serial8250_set_divisor(struct uart_port *port, unsigned int baud,
-			    unsigned int quot, unsigned int quot_frac)
-{
-	struct uart_8250_port *up = up_to_u8250p(port);
-
-	/* Workaround to enable 115200 baud on OMAP1510 internal ports */
-	if (is_omap1510_8250(up)) {
-		if (baud == 115200) {
-			quot = 1;
-			serial_port_out(port, UART_OMAP_OSC_12M_SEL, 1);
-		} else
-			serial_port_out(port, UART_OMAP_OSC_12M_SEL, 0);
-	}
-
-	/*
-	 * For NatSemi, switch to bank 2 not bank 1, to avoid resetting EXCR2,
-	 * otherwise just set DLAB
-	 */
-	if (up->capabilities & UART_NATSEMI)
-		serial_port_out(port, UART_LCR, 0xe0);
-	else
-		serial_port_out(port, UART_LCR, up->lcr | UART_LCR_DLAB);
-
-	serial_dl_write(up, quot);
-
-	/* XR17V35x UARTs have an extra fractional divisor register (DLD) */
-	if (up->port.type == PORT_XR17V35X)
-		serial_port_out(port, 0x2, quot_frac);
-}
-
-void
-serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios,
-		          struct ktermios *old)
-{
-	struct uart_8250_port *up = up_to_u8250p(port);
-	unsigned char cval;
-	unsigned long flags;
-	unsigned int baud, quot, frac = 0;
-
-	cval = serial8250_compute_lcr(up, termios->c_cflag);
-
-	/*
-	 * Ask the core to calculate the divisor for us.
-	 */
-	baud = uart_get_baud_rate(port, termios, old,
-				  port->uartclk / 16 / 0xffff,
-				  port->uartclk / 16);
-	quot = serial8250_get_divisor(up, baud, &frac);
-
-	/*
-	 * Ok, we're now changing the port state.  Do it with
-	 * interrupts disabled.
-	 */
-	serial8250_rpm_get(up);
-	spin_lock_irqsave(&port->lock, flags);
-
-	up->lcr = cval;					/* Save computed LCR */
-
-	if (up->capabilities & UART_CAP_FIFO && port->fifosize > 1) {
-		/* NOTE: If fifo_bug is not set, a user can set RX_trigger. */
-		if ((baud < 2400 && !up->dma) || up->fifo_bug) {
-			up->fcr &= ~UART_FCR_TRIGGER_MASK;
-			up->fcr |= UART_FCR_TRIGGER_1;
-		}
-	}
-
-	/*
-	 * MCR-based auto flow control.  When AFE is enabled, RTS will be
-	 * deasserted when the receive FIFO contains more characters than
-	 * the trigger, or the MCR RTS bit is cleared.  In the case where
-	 * the remote UART is not using CTS auto flow control, we must
-	 * have sufficient FIFO entries for the latency of the remote
-	 * UART to respond.  IOW, at least 32 bytes of FIFO.
-	 */
-	if (up->capabilities & UART_CAP_AFE && port->fifosize >= 32) {
-		up->mcr &= ~UART_MCR_AFE;
-		if (termios->c_cflag & CRTSCTS)
-			up->mcr |= UART_MCR_AFE;
-	}
-
-	/*
-	 * Update the per-port timeout.
-	 */
-	uart_update_timeout(port, termios->c_cflag, baud);
-
-	port->read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
-	if (termios->c_iflag & INPCK)
-		port->read_status_mask |= UART_LSR_FE | UART_LSR_PE;
-	if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
-		port->read_status_mask |= UART_LSR_BI;
-
-	/*
-	 * Characteres to ignore
-	 */
-	port->ignore_status_mask = 0;
-	if (termios->c_iflag & IGNPAR)
-		port->ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
-	if (termios->c_iflag & IGNBRK) {
-		port->ignore_status_mask |= UART_LSR_BI;
-		/*
-		 * If we're ignoring parity and break indicators,
-		 * ignore overruns too (for real raw support).
-		 */
-		if (termios->c_iflag & IGNPAR)
-			port->ignore_status_mask |= UART_LSR_OE;
-	}
-
-	/*
-	 * ignore all characters if CREAD is not set
-	 */
-	if ((termios->c_cflag & CREAD) == 0)
-		port->ignore_status_mask |= UART_LSR_DR;
-
-	/*
-	 * CTS flow control flag and modem status interrupts
-	 */
-	up->ier &= ~UART_IER_MSI;
-	if (!(up->bugs & UART_BUG_NOMSR) &&
-			UART_ENABLE_MS(&up->port, termios->c_cflag))
-		up->ier |= UART_IER_MSI;
-	if (up->capabilities & UART_CAP_UUE)
-		up->ier |= UART_IER_UUE;
-	if (up->capabilities & UART_CAP_RTOIE)
-		up->ier |= UART_IER_RTOIE;
-
-	serial_port_out(port, UART_IER, up->ier);
-
-	if (up->capabilities & UART_CAP_EFR) {
-		unsigned char efr = 0;
-		/*
-		 * TI16C752/Startech hardware flow control.  FIXME:
-		 * - TI16C752 requires control thresholds to be set.
-		 * - UART_MCR_RTS is ineffective if auto-RTS mode is enabled.
-		 */
-		if (termios->c_cflag & CRTSCTS)
-			efr |= UART_EFR_CTS;
-
-		serial_port_out(port, UART_LCR, UART_LCR_CONF_MODE_B);
-		if (port->flags & UPF_EXAR_EFR)
-			serial_port_out(port, UART_XR_EFR, efr);
-		else
-			serial_port_out(port, UART_EFR, efr);
-	}
-
-	serial8250_set_divisor(port, baud, quot, frac);
+	spin_lock_irqsave(&up->port.lock, flags);
 
 	/*
-	 * LCR DLAB must be set to enable 64-byte FIFO mode. If the FCR
-	 * is written without DLAB set, this mode will be disabled.
+	 * Must disable interrupts or else we risk racing with the interrupt
+	 * based handler.
 	 */
-	if (port->type == PORT_16750)
-		serial_port_out(port, UART_FCR, up->fcr);
-
-	serial_port_out(port, UART_LCR, up->lcr);	/* reset DLAB */
-	if (port->type != PORT_16750) {
-		/* emulated UARTs (Lucent Venus 167x) need two steps */
-		if (up->fcr & UART_FCR_ENABLE_FIFO)
-			serial_port_out(port, UART_FCR, UART_FCR_ENABLE_FIFO);
-		serial_port_out(port, UART_FCR, up->fcr);	/* set fcr */
-	}
-	serial8250_set_mctrl(port, port->mctrl);
-	spin_unlock_irqrestore(&port->lock, flags);
-	serial8250_rpm_put(up);
-
-	/* Don't rewrite B0 */
-	if (tty_termios_baud_rate(termios))
-		tty_termios_encode_baud_rate(termios, baud, baud);
-}
-EXPORT_SYMBOL(serial8250_do_set_termios);
-
-static void
-serial8250_set_termios(struct uart_port *port, struct ktermios *termios,
-		       struct ktermios *old)
-{
-	if (port->set_termios)
-		port->set_termios(port, termios, old);
-	else
-		serial8250_do_set_termios(port, termios, old);
-}
-
-static void
-serial8250_set_ldisc(struct uart_port *port, struct ktermios *termios)
-{
-	if (termios->c_line == N_PPS) {
-		port->flags |= UPF_HARDPPS_CD;
-		spin_lock_irq(&port->lock);
-		serial8250_enable_ms(port);
-		spin_unlock_irq(&port->lock);
-	} else {
-		port->flags &= ~UPF_HARDPPS_CD;
-		if (!UART_ENABLE_MS(port, termios->c_cflag)) {
-			spin_lock_irq(&port->lock);
-			serial8250_disable_ms(port);
-			spin_unlock_irq(&port->lock);
-		}
+	if (up->port.irq) {
+		ier = serial_in(up, UART_IER);
+		serial_out(up, UART_IER, 0);
 	}
-}
 
+	iir = serial_in(up, UART_IIR);
 
-void serial8250_do_pm(struct uart_port *port, unsigned int state,
-		      unsigned int oldstate)
-{
-	struct uart_8250_port *p = up_to_u8250p(port);
+	/*
+	 * This should be a safe test for anyone who doesn't trust the
+	 * IIR bits on their UART, but it's specifically designed for
+	 * the "Diva" UART used on the management processor on many HP
+	 * ia64 and parisc boxes.
+	 */
+	lsr = serial_in(up, UART_LSR);
+	up->lsr_saved_flags |= lsr & LSR_SAVE_FLAGS;
+	if ((iir & UART_IIR_NO_INT) && (up->ier & UART_IER_THRI) &&
+	    (!uart_circ_empty(&up->port.state->xmit) || up->port.x_char) &&
+	    (lsr & UART_LSR_THRE)) {
+		iir &= ~(UART_IIR_ID | UART_IIR_NO_INT);
+		iir |= UART_IIR_THRI;
+	}
 
-	serial8250_set_sleep(p, state != 0);
-}
-EXPORT_SYMBOL(serial8250_do_pm);
+	if (!(iir & UART_IIR_NO_INT))
+		serial8250_tx_chars(up);
 
-static void
-serial8250_pm(struct uart_port *port, unsigned int state,
-	      unsigned int oldstate)
-{
-	if (port->pm)
-		port->pm(port, state, oldstate);
-	else
-		serial8250_do_pm(port, state, oldstate);
-}
+	if (up->port.irq)
+		serial_out(up, UART_IER, ier);
 
-static unsigned int serial8250_port_size(struct uart_8250_port *pt)
-{
-	if (pt->port.mapsize)
-		return pt->port.mapsize;
-	if (pt->port.iotype == UPIO_AU) {
-		if (pt->port.type == PORT_RT2880)
-			return 0x100;
-		return 0x1000;
-	}
-	if (is_omap1_8250(pt))
-		return 0x16 << pt->port.regshift;
+	spin_unlock_irqrestore(&up->port.lock, flags);
 
-	return 8 << pt->port.regshift;
+	/* Standard timer interval plus 0.2s to keep the port running */
+	mod_timer(&up->timer,
+		jiffies + uart_poll_timeout(&up->port) + HZ / 5);
 }
 
-/*
- * Resource handling.
- */
-static int serial8250_request_std_resource(struct uart_8250_port *up)
+static int univ8250_setup_irq(struct uart_8250_port *up)
 {
-	unsigned int size = serial8250_port_size(up);
 	struct uart_port *port = &up->port;
-	int ret = 0;
+	int retval = 0;
 
-	switch (port->iotype) {
-	case UPIO_AU:
-	case UPIO_TSI:
-	case UPIO_MEM32:
-	case UPIO_MEM32BE:
-	case UPIO_MEM:
-		if (!port->mapbase)
-			break;
+	/*
+	 * The above check will only give an accurate result the first time
+	 * the port is opened so this value needs to be preserved.
+	 */
+	if (up->bugs & UART_BUG_THRE) {
+		pr_debug("ttyS%d - using backup timer\n", serial_index(port));
 
-		if (!request_mem_region(port->mapbase, size, "serial")) {
-			ret = -EBUSY;
-			break;
-		}
+		up->timer.function = serial8250_backup_timeout;
+		up->timer.data = (unsigned long)up;
+		mod_timer(&up->timer, jiffies +
+			  uart_poll_timeout(port) + HZ / 5);
+	}
 
-		if (port->flags & UPF_IOREMAP) {
-			port->membase = ioremap_nocache(port->mapbase, size);
-			if (!port->membase) {
-				release_mem_region(port->mapbase, size);
-				ret = -ENOMEM;
-			}
-		}
-		break;
+	/*
+	 * If the "interrupt" for this port doesn't correspond with any
+	 * hardware interrupt, we use a timer-based system.  The original
+	 * driver used to do this with IRQ0.
+	 */
+	if (!port->irq) {
+		up->timer.data = (unsigned long)up;
+		mod_timer(&up->timer, jiffies + uart_poll_timeout(port));
+	} else
+		retval = serial_link_irq_chain(up);
 
-	case UPIO_HUB6:
-	case UPIO_PORT:
-		if (!request_region(port->iobase, size, "serial"))
-			ret = -EBUSY;
-		break;
-	}
-	return ret;
+	return retval;
 }
 
-static void serial8250_release_std_resource(struct uart_8250_port *up)
+static void univ8250_release_irq(struct uart_8250_port *up)
 {
-	unsigned int size = serial8250_port_size(up);
 	struct uart_port *port = &up->port;
 
-	switch (port->iotype) {
-	case UPIO_AU:
-	case UPIO_TSI:
-	case UPIO_MEM32:
-	case UPIO_MEM32BE:
-	case UPIO_MEM:
-		if (!port->mapbase)
-			break;
-
-		if (port->flags & UPF_IOREMAP) {
-			iounmap(port->membase);
-			port->membase = NULL;
-		}
-
-		release_mem_region(port->mapbase, size);
-		break;
-
-	case UPIO_HUB6:
-	case UPIO_PORT:
-		release_region(port->iobase, size);
-		break;
-	}
+	del_timer_sync(&up->timer);
+	up->timer.function = serial8250_timeout;
+	if (port->irq)
+		serial_unlink_irq_chain(up);
 }
 
 #ifdef CONFIG_SERIAL_8250_RSA
@@ -2848,259 +396,6 @@ static void serial8250_release_rsa_resource(struct uart_8250_port *up)
 }
 #endif
 
-static void serial8250_release_port(struct uart_port *port)
-{
-	struct uart_8250_port *up = up_to_u8250p(port);
-
-	serial8250_release_std_resource(up);
-}
-
-static int serial8250_request_port(struct uart_port *port)
-{
-	struct uart_8250_port *up = up_to_u8250p(port);
-	int ret;
-
-	if (port->type == PORT_8250_CIR)
-		return -ENODEV;
-
-	ret = serial8250_request_std_resource(up);
-
-	return ret;
-}
-
-static int fcr_get_rxtrig_bytes(struct uart_8250_port *up)
-{
-	const struct serial8250_config *conf_type = &uart_config[up->port.type];
-	unsigned char bytes;
-
-	bytes = conf_type->rxtrig_bytes[UART_FCR_R_TRIG_BITS(up->fcr)];
-
-	return bytes ? bytes : -EOPNOTSUPP;
-}
-
-static int bytes_to_fcr_rxtrig(struct uart_8250_port *up, unsigned char bytes)
-{
-	const struct serial8250_config *conf_type = &uart_config[up->port.type];
-	int i;
-
-	if (!conf_type->rxtrig_bytes[UART_FCR_R_TRIG_BITS(UART_FCR_R_TRIG_00)])
-		return -EOPNOTSUPP;
-
-	for (i = 1; i < UART_FCR_R_TRIG_MAX_STATE; i++) {
-		if (bytes < conf_type->rxtrig_bytes[i])
-			/* Use the nearest lower value */
-			return (--i) << UART_FCR_R_TRIG_SHIFT;
-	}
-
-	return UART_FCR_R_TRIG_11;
-}
-
-static int do_get_rxtrig(struct tty_port *port)
-{
-	struct uart_state *state = container_of(port, struct uart_state, port);
-	struct uart_port *uport = state->uart_port;
-	struct uart_8250_port *up =
-		container_of(uport, struct uart_8250_port, port);
-
-	if (!(up->capabilities & UART_CAP_FIFO) || uport->fifosize <= 1)
-		return -EINVAL;
-
-	return fcr_get_rxtrig_bytes(up);
-}
-
-static int do_serial8250_get_rxtrig(struct tty_port *port)
-{
-	int rxtrig_bytes;
-
-	mutex_lock(&port->mutex);
-	rxtrig_bytes = do_get_rxtrig(port);
-	mutex_unlock(&port->mutex);
-
-	return rxtrig_bytes;
-}
-
-static ssize_t serial8250_get_attr_rx_trig_bytes(struct device *dev,
-	struct device_attribute *attr, char *buf)
-{
-	struct tty_port *port = dev_get_drvdata(dev);
-	int rxtrig_bytes;
-
-	rxtrig_bytes = do_serial8250_get_rxtrig(port);
-	if (rxtrig_bytes < 0)
-		return rxtrig_bytes;
-
-	return snprintf(buf, PAGE_SIZE, "%d\n", rxtrig_bytes);
-}
-
-static int do_set_rxtrig(struct tty_port *port, unsigned char bytes)
-{
-	struct uart_state *state = container_of(port, struct uart_state, port);
-	struct uart_port *uport = state->uart_port;
-	struct uart_8250_port *up =
-		container_of(uport, struct uart_8250_port, port);
-	int rxtrig;
-
-	if (!(up->capabilities & UART_CAP_FIFO) || uport->fifosize <= 1 ||
-	    up->fifo_bug)
-		return -EINVAL;
-
-	rxtrig = bytes_to_fcr_rxtrig(up, bytes);
-	if (rxtrig < 0)
-		return rxtrig;
-
-	serial8250_clear_fifos(up);
-	up->fcr &= ~UART_FCR_TRIGGER_MASK;
-	up->fcr |= (unsigned char)rxtrig;
-	serial_out(up, UART_FCR, up->fcr);
-	return 0;
-}
-
-static int do_serial8250_set_rxtrig(struct tty_port *port, unsigned char bytes)
-{
-	int ret;
-
-	mutex_lock(&port->mutex);
-	ret = do_set_rxtrig(port, bytes);
-	mutex_unlock(&port->mutex);
-
-	return ret;
-}
-
-static ssize_t serial8250_set_attr_rx_trig_bytes(struct device *dev,
-	struct device_attribute *attr, const char *buf, size_t count)
-{
-	struct tty_port *port = dev_get_drvdata(dev);
-	unsigned char bytes;
-	int ret;
-
-	if (!count)
-		return -EINVAL;
-
-	ret = kstrtou8(buf, 10, &bytes);
-	if (ret < 0)
-		return ret;
-
-	ret = do_serial8250_set_rxtrig(port, bytes);
-	if (ret < 0)
-		return ret;
-
-	return count;
-}
-
-static DEVICE_ATTR(rx_trig_bytes, S_IRUSR | S_IWUSR | S_IRGRP,
-		   serial8250_get_attr_rx_trig_bytes,
-		   serial8250_set_attr_rx_trig_bytes);
-
-static struct attribute *serial8250_dev_attrs[] = {
-	&dev_attr_rx_trig_bytes.attr,
-	NULL,
-	};
-
-static struct attribute_group serial8250_dev_attr_group = {
-	.attrs = serial8250_dev_attrs,
-	};
-
-static void register_dev_spec_attr_grp(struct uart_8250_port *up)
-{
-	const struct serial8250_config *conf_type = &uart_config[up->port.type];
-
-	if (conf_type->rxtrig_bytes[0])
-		up->port.attr_group = &serial8250_dev_attr_group;
-}
-
-static void serial8250_config_port(struct uart_port *port, int flags)
-{
-	struct uart_8250_port *up = up_to_u8250p(port);
-	int ret;
-
-	if (port->type == PORT_8250_CIR)
-		return;
-
-	/*
-	 * Find the region that we can probe for.  This in turn
-	 * tells us whether we can probe for the type of port.
-	 */
-	ret = serial8250_request_std_resource(up);
-	if (ret < 0)
-		return;
-
-	if (port->iotype != up->cur_iotype)
-		set_io_from_upio(port);
-
-	if (flags & UART_CONFIG_TYPE)
-		autoconfig(up);
-
-	/* if access method is AU, it is a 16550 with a quirk */
-	if (port->type == PORT_16550A && port->iotype == UPIO_AU)
-		up->bugs |= UART_BUG_NOMSR;
-
-	/* HW bugs may trigger IRQ while IIR == NO_INT */
-	if (port->type == PORT_TEGRA)
-		up->bugs |= UART_BUG_NOMSR;
-
-	if (port->type != PORT_UNKNOWN && flags & UART_CONFIG_IRQ)
-		autoconfig_irq(up);
-
-	if (port->type == PORT_UNKNOWN)
-		serial8250_release_std_resource(up);
-
-	/* Fixme: probably not the best place for this */
-	if ((port->type == PORT_XR17V35X) ||
-	   (port->type == PORT_XR17D15X))
-		port->handle_irq = exar_handle_irq;
-
-	register_dev_spec_attr_grp(up);
-	up->fcr = uart_config[up->port.type].fcr;
-}
-
-static int
-serial8250_verify_port(struct uart_port *port, struct serial_struct *ser)
-{
-	if (ser->irq >= nr_irqs || ser->irq < 0 ||
-	    ser->baud_base < 9600 || ser->type < PORT_UNKNOWN ||
-	    ser->type >= ARRAY_SIZE(uart_config) || ser->type == PORT_CIRRUS ||
-	    ser->type == PORT_STARTECH)
-		return -EINVAL;
-	return 0;
-}
-
-static const char *
-serial8250_type(struct uart_port *port)
-{
-	int type = port->type;
-
-	if (type >= ARRAY_SIZE(uart_config))
-		type = 0;
-	return uart_config[type].name;
-}
-
-static const struct uart_ops serial8250_pops = {
-	.tx_empty	= serial8250_tx_empty,
-	.set_mctrl	= serial8250_set_mctrl,
-	.get_mctrl	= serial8250_get_mctrl,
-	.stop_tx	= serial8250_stop_tx,
-	.start_tx	= serial8250_start_tx,
-	.throttle	= serial8250_throttle,
-	.unthrottle	= serial8250_unthrottle,
-	.stop_rx	= serial8250_stop_rx,
-	.enable_ms	= serial8250_enable_ms,
-	.break_ctl	= serial8250_break_ctl,
-	.startup	= serial8250_startup,
-	.shutdown	= serial8250_shutdown,
-	.set_termios	= serial8250_set_termios,
-	.set_ldisc	= serial8250_set_ldisc,
-	.pm		= serial8250_pm,
-	.type		= serial8250_type,
-	.release_port	= serial8250_release_port,
-	.request_port	= serial8250_request_port,
-	.config_port	= serial8250_config_port,
-	.verify_port	= serial8250_verify_port,
-#ifdef CONFIG_CONSOLE_POLL
-	.poll_get_char = serial8250_get_poll_char,
-	.poll_put_char = serial8250_put_poll_char,
-#endif
-};
-
 static const struct uart_ops *base_ops;
 static struct uart_ops univ8250_port_ops;
 
@@ -3139,42 +434,6 @@ void serial8250_set_isa_configurator(
 }
 EXPORT_SYMBOL(serial8250_set_isa_configurator);
 
-static void serial8250_init_port(struct uart_8250_port *up)
-{
-	struct uart_port *port = &up->port;
-
-	spin_lock_init(&port->lock);
-	port->ops = &serial8250_pops;
-
-	up->cur_iotype = 0xFF;
-}
-
-static void serial8250_set_defaults(struct uart_8250_port *up)
-{
-	struct uart_port *port = &up->port;
-
-	if (up->port.flags & UPF_FIXED_TYPE) {
-		unsigned int type = up->port.type;
-
-		if (!up->port.fifosize)
-			up->port.fifosize = uart_config[type].fifo_size;
-		if (!up->tx_loadsz)
-			up->tx_loadsz = uart_config[type].tx_loadsz;
-		if (!up->capabilities)
-			up->capabilities = uart_config[type].flags;
-	}
-
-	set_io_from_upio(port);
-
-	/* default dma handlers */
-	if (up->dma) {
-		if (!up->dma->tx_dma)
-			up->dma->tx_dma = serial8250_tx_dma;
-		if (!up->dma->rx_dma)
-			up->dma->rx_dma = serial8250_rx_dma;
-	}
-}
-
 #ifdef CONFIG_SERIAL_8250_RSA
 
 static void univ8250_config_port(struct uart_port *port, int flags)
@@ -3324,94 +583,6 @@ serial8250_register_ports(struct uart_driver *drv, struct device *dev)
 
 #ifdef CONFIG_SERIAL_8250_CONSOLE
 
-static void serial8250_console_putchar(struct uart_port *port, int ch)
-{
-	struct uart_8250_port *up = up_to_u8250p(port);
-
-	wait_for_xmitr(up, UART_LSR_THRE);
-	serial_port_out(port, UART_TX, ch);
-}
-
-/*
- *	Print a string to the serial port trying not to disturb
- *	any possible real use of the port...
- *
- *	The console_lock must be held when we get here.
- */
-static void serial8250_console_write(struct uart_8250_port *up, const char *s,
-				     unsigned int count)
-{
-	struct uart_port *port = &up->port;
-	unsigned long flags;
-	unsigned int ier;
-	int locked = 1;
-
-	touch_nmi_watchdog();
-
-	serial8250_rpm_get(up);
-
-	if (port->sysrq)
-		locked = 0;
-	else if (oops_in_progress)
-		locked = spin_trylock_irqsave(&port->lock, flags);
-	else
-		spin_lock_irqsave(&port->lock, flags);
-
-	/*
-	 *	First save the IER then disable the interrupts
-	 */
-	ier = serial_port_in(port, UART_IER);
-
-	if (up->capabilities & UART_CAP_UUE)
-		serial_port_out(port, UART_IER, UART_IER_UUE);
-	else
-		serial_port_out(port, UART_IER, 0);
-
-	/* check scratch reg to see if port powered off during system sleep */
-	if (up->canary && (up->canary != serial_port_in(port, UART_SCR))) {
-		struct ktermios termios;
-		unsigned int baud, quot, frac = 0;
-
-		termios.c_cflag = port->cons->cflag;
-		if (port->state->port.tty && termios.c_cflag == 0)
-			termios.c_cflag = port->state->port.tty->termios.c_cflag;
-
-		baud = uart_get_baud_rate(port, &termios, NULL,
-					  port->uartclk / 16 / 0xffff,
-					  port->uartclk / 16);
-		quot = serial8250_get_divisor(up, baud, &frac);
-
-		serial8250_set_divisor(port, baud, quot, frac);
-		serial_port_out(port, UART_LCR, up->lcr);
-		serial_port_out(port, UART_MCR, UART_MCR_DTR | UART_MCR_RTS);
-
-		up->canary = 0;
-	}
-
-	uart_console_write(port, s, count, serial8250_console_putchar);
-
-	/*
-	 *	Finally, wait for transmitter to become empty
-	 *	and restore the IER
-	 */
-	wait_for_xmitr(up, BOTH_EMPTY);
-	serial_port_out(port, UART_IER, ier);
-
-	/*
-	 *	The receive handling will happen properly because the
-	 *	receive ready bit will still be set; it is not cleared
-	 *	on read.  However, modem control will not, we must
-	 *	call it if we have saved something in the saved flags
-	 *	while processing with interrupts off.
-	 */
-	if (up->msr_saved_flags)
-		serial8250_modem_status(up);
-
-	if (locked)
-		spin_unlock_irqrestore(&port->lock, flags);
-	serial8250_rpm_put(up);
-}
-
 static void univ8250_console_write(struct console *co, const char *s,
 				   unsigned int count)
 {
@@ -3420,39 +591,6 @@ static void univ8250_console_write(struct console *co, const char *s,
 	serial8250_console_write(up, s, count);
 }
 
-static unsigned int probe_baud(struct uart_port *port)
-{
-	unsigned char lcr, dll, dlm;
-	unsigned int quot;
-
-	lcr = serial_port_in(port, UART_LCR);
-	serial_port_out(port, UART_LCR, lcr | UART_LCR_DLAB);
-	dll = serial_port_in(port, UART_DLL);
-	dlm = serial_port_in(port, UART_DLM);
-	serial_port_out(port, UART_LCR, lcr);
-
-	quot = (dlm << 8) | dll;
-	return (port->uartclk / 16) / quot;
-}
-
-static int serial8250_console_setup(struct uart_port *port, char *options, bool probe)
-{
-	int baud = 9600;
-	int bits = 8;
-	int parity = 'n';
-	int flow = 'n';
-
-	if (!port->iobase && !port->membase)
-		return -ENODEV;
-
-	if (options)
-		uart_parse_options(options, &baud, &parity, &bits, &flow);
-	else if (probe)
-		baud = probe_baud(port);
-
-	return uart_set_options(port, port->cons, baud, parity, bits, flow);
-}
-
 static int univ8250_console_setup(struct console *co, char *options)
 {
 	struct uart_port *port;

drivers/tty/serial/8250/8250_dw.c

@@ -56,7 +56,6 @@
 
 struct dw8250_data {
 	u8			usr_reg;
-	int			last_mcr;
 	int			line;
 	int			msr_mask_on;
 	int			msr_mask_off;
@@ -76,12 +75,6 @@ static inline int dw8250_modify_msr(struct uart_port *p, int offset, int value)
 {
 	struct dw8250_data *d = p->private_data;
 
-	/* If reading MSR, report CTS asserted when auto-CTS/RTS enabled */
-	if (offset == UART_MSR && d->last_mcr & UART_MCR_AFE) {
-		value |= UART_MSR_CTS;
-		value &= ~UART_MSR_DCTS;
-	}
-
 	/* Override any modem control signals if needed */
 	if (offset == UART_MSR) {
 		value |= d->msr_mask_on;
@@ -101,11 +94,6 @@ static void dw8250_force_idle(struct uart_port *p)
 
 static void dw8250_serial_out(struct uart_port *p, int offset, int value)
 {
-	struct dw8250_data *d = p->private_data;
-
-	if (offset == UART_MCR)
-		d->last_mcr = value;
-
 	writeb(value, p->membase + (offset << p->regshift));
 
 	/* Make sure LCR write wasn't ignored */
@@ -144,11 +132,6 @@ static unsigned int dw8250_serial_inq(struct uart_port *p, int offset)
 
 static void dw8250_serial_outq(struct uart_port *p, int offset, int value)
 {
-	struct dw8250_data *d = p->private_data;
-
-	if (offset == UART_MCR)
-		d->last_mcr = value;
-
 	value &= 0xff;
 	__raw_writeq(value, p->membase + (offset << p->regshift));
 	/* Read back to ensure register write ordering. */
@@ -175,11 +158,6 @@ static void dw8250_serial_outq(struct uart_port *p, int offset, int value)
 
 static void dw8250_serial_out32(struct uart_port *p, int offset, int value)
 {
-	struct dw8250_data *d = p->private_data;
-
-	if (offset == UART_MCR)
-		d->last_mcr = value;
-
 	writel(value, p->membase + (offset << p->regshift));
 
 	/* Make sure LCR write wasn't ignored */
@@ -257,6 +235,11 @@ static void dw8250_set_termios(struct uart_port *p, struct ktermios *termios,
 
 	if (!ret)
 		p->uartclk = rate;
+
+	p->status &= ~UPSTAT_AUTOCTS;
+	if (termios->c_cflag & CRTSCTS)
+		p->status |= UPSTAT_AUTOCTS;
+
 out:
 	serial8250_do_set_termios(p, termios, old);
 }

drivers/tty/serial/8250/8250_early.c

@@ -35,7 +35,7 @@
 #include <asm/io.h>
 #include <asm/serial.h>
 
-unsigned int __weak __init serial8250_early_in(struct uart_port *port, int offset)
+static unsigned int __init serial8250_early_in(struct uart_port *port, int offset)
 {
 	switch (port->iotype) {
 	case UPIO_MEM:
@@ -51,7 +51,7 @@ unsigned int __weak __init serial8250_early_in(struct uart_port *port, int offse
 	}
 }
 
-void __weak __init serial8250_early_out(struct uart_port *port, int offset, int value)
+static void __init serial8250_early_out(struct uart_port *port, int offset, int value)
 {
 	switch (port->iotype) {
 	case UPIO_MEM:

drivers/tty/serial/8250/8250_fintek.c

@@ -17,18 +17,19 @@
 #include <linux/serial_core.h>
 #include  "8250.h"
 
-#define ADDR_PORT 0x4E
-#define DATA_PORT 0x4F
-#define ENTRY_KEY 0x77
+#define ADDR_PORT 0
+#define DATA_PORT 1
 #define EXIT_KEY 0xAA
 #define CHIP_ID1  0x20
-#define CHIP_ID1_VAL 0x02
 #define CHIP_ID2  0x21
-#define CHIP_ID2_VAL 0x16
+#define CHIP_ID_0 0x1602
+#define CHIP_ID_1 0x0501
 #define VENDOR_ID1 0x23
 #define VENDOR_ID1_VAL 0x19
 #define VENDOR_ID2 0x24
 #define VENDOR_ID2_VAL 0x34
+#define IO_ADDR1 0x61
+#define IO_ADDR2 0x60
 #define LDN 0x7
 
 #define RS485  0xF0
@@ -39,51 +40,49 @@
 
 #define DRIVER_NAME "8250_fintek"
 
-static int fintek_8250_enter_key(void){
+struct fintek_8250 {
+	u16 base_port;
+	u8 index;
+	u8 key;
+	long line;
+};
+
+static int fintek_8250_enter_key(u16 base_port, u8 key)
+{
 
-	if (!request_muxed_region(ADDR_PORT, 2, DRIVER_NAME))
+	if (!request_muxed_region(base_port, 2, DRIVER_NAME))
 		return -EBUSY;
 
-	outb(ENTRY_KEY, ADDR_PORT);
-	outb(ENTRY_KEY, ADDR_PORT);
+	outb(key, base_port + ADDR_PORT);
+	outb(key, base_port + ADDR_PORT);
 	return 0;
 }
 
-static void fintek_8250_exit_key(void){
-
-	outb(EXIT_KEY, ADDR_PORT);
-	release_region(ADDR_PORT, 2);
-}
-
-static int fintek_8250_get_index(resource_size_t base_addr)
+static void fintek_8250_exit_key(u16 base_port)
 {
-	resource_size_t base[] = {0x3f8, 0x2f8, 0x3e8, 0x2e8};
-	int i;
-
-	for (i = 0; i < ARRAY_SIZE(base); i++)
-		if (base_addr == base[i])
-			return i;
 
-	return -ENODEV;
+	outb(EXIT_KEY, base_port + ADDR_PORT);
+	release_region(base_port + ADDR_PORT, 2);
 }
 
-static int fintek_8250_check_id(void)
+static int fintek_8250_check_id(u16 base_port)
 {
+	u16 chip;
 
-	outb(CHIP_ID1, ADDR_PORT);
-	if (inb(DATA_PORT) != CHIP_ID1_VAL)
+	outb(VENDOR_ID1, base_port + ADDR_PORT);
+	if (inb(base_port + DATA_PORT) != VENDOR_ID1_VAL)
 		return -ENODEV;
 
-	outb(CHIP_ID2, ADDR_PORT);
-	if (inb(DATA_PORT) != CHIP_ID2_VAL)
+	outb(VENDOR_ID2, base_port + ADDR_PORT);
+	if (inb(base_port + DATA_PORT) != VENDOR_ID2_VAL)
 		return -ENODEV;
 
-	outb(VENDOR_ID1, ADDR_PORT);
-	if (inb(DATA_PORT) != VENDOR_ID1_VAL)
-		return -ENODEV;
+	outb(CHIP_ID1, base_port + ADDR_PORT);
+	chip = inb(base_port + DATA_PORT);
+	outb(CHIP_ID2, base_port + ADDR_PORT);
+	chip |= inb(base_port + DATA_PORT) << 8;
 
-	outb(VENDOR_ID2, ADDR_PORT);
-	if (inb(DATA_PORT) != VENDOR_ID2_VAL)
+	if (chip != CHIP_ID_0 && chip != CHIP_ID_1)
 		return -ENODEV;
 
 	return 0;
@@ -93,9 +92,9 @@ static int fintek_8250_rs485_config(struct uart_port *port,
 			      struct serial_rs485 *rs485)
 {
 	uint8_t config = 0;
-	int index = fintek_8250_get_index(port->iobase);
+	struct fintek_8250 *pdata = port->private_data;
 
-	if (index < 0)
+	if (!pdata)
 		return -EINVAL;
 
 	if (rs485->flags & SER_RS485_ENABLED)
@@ -125,44 +124,84 @@ static int fintek_8250_rs485_config(struct uart_port *port,
 	if (rs485->flags & SER_RS485_RTS_ON_SEND)
 		config |= RTS_INVERT;
 
-	if (fintek_8250_enter_key())
+	if (fintek_8250_enter_key(pdata->base_port, pdata->key))
 		return -EBUSY;
 
-	outb(LDN, ADDR_PORT);
-	outb(index, DATA_PORT);
-	outb(RS485, ADDR_PORT);
-	outb(config, DATA_PORT);
-	fintek_8250_exit_key();
+	outb(LDN, pdata->base_port + ADDR_PORT);
+	outb(pdata->index, pdata->base_port + DATA_PORT);
+	outb(RS485, pdata->base_port + ADDR_PORT);
+	outb(config, pdata->base_port + DATA_PORT);
+	fintek_8250_exit_key(pdata->base_port);
 
 	port->rs485 = *rs485;
 
 	return 0;
 }
 
+static int fintek_8250_base_port(u16 io_address, u8 *key, u8 *index)
+{
+	static const u16 addr[] = {0x4e, 0x2e};
+	static const u8 keys[] = {0x77, 0xa0, 0x87, 0x67};
+	int i, j, k;
+
+	for (i = 0; i < ARRAY_SIZE(addr); i++) {
+		for (j = 0; j < ARRAY_SIZE(keys); j++) {
+
+			if (fintek_8250_enter_key(addr[i], keys[j]))
+				continue;
+			if (fintek_8250_check_id(addr[i])) {
+				fintek_8250_exit_key(addr[i]);
+				continue;
+			}
+
+			for (k = 0; k < 4; k++) {
+				u16 aux;
+
+				outb(LDN, addr[i] + ADDR_PORT);
+				outb(k, addr[i] + DATA_PORT);
+
+				outb(IO_ADDR1, addr[i] + ADDR_PORT);
+				aux = inb(addr[i] + DATA_PORT);
+				outb(IO_ADDR2, addr[i] + ADDR_PORT);
+				aux |= inb(addr[i] + DATA_PORT) << 8;
+				if (aux != io_address)
+					continue;
+
+				fintek_8250_exit_key(addr[i]);
+				*key = keys[j];
+				*index = k;
+				return addr[i];
+			}
+			fintek_8250_exit_key(addr[i]);
+		}
+	}
+
+	return -ENODEV;
+}
+
 static int
 fintek_8250_probe(struct pnp_dev *dev, const struct pnp_device_id *dev_id)
 {
-	int line;
 	struct uart_8250_port uart;
-	int ret;
+	struct fintek_8250 *pdata;
+	int base_port;
+	u8 key;
+	u8 index;
 
 	if (!pnp_port_valid(dev, 0))
 		return -ENODEV;
 
-	if (fintek_8250_get_index(pnp_port_start(dev, 0)) < 0)
+	base_port = fintek_8250_base_port(pnp_port_start(dev, 0), &key, &index);
+	if (base_port < 0)
 		return -ENODEV;
 
-	/* Enable configuration registers*/
-	if (fintek_8250_enter_key())
-		return -EBUSY;
+	memset(&uart, 0, sizeof(uart));
 
-	/*Check ID*/
-	ret = fintek_8250_check_id();
-	fintek_8250_exit_key();
-	if (ret)
-		return ret;
+	pdata = devm_kzalloc(&dev->dev, sizeof(*pdata), GFP_KERNEL);
+	if (!pdata)
+		return -ENOMEM;
+	uart.port.private_data = pdata;
 
-	memset(&uart, 0, sizeof(uart));
 	if (!pnp_irq_valid(dev, 0))
 		return -ENODEV;
 	uart.port.irq = pnp_irq(dev, 0);
@@ -176,40 +215,43 @@ fintek_8250_probe(struct pnp_dev *dev, const struct pnp_device_id *dev_id)
 	uart.port.uartclk = 1843200;
 	uart.port.dev = &dev->dev;
 
-	line = serial8250_register_8250_port(&uart);
-	if (line < 0)
+	pdata->key = key;
+	pdata->base_port = base_port;
+	pdata->index = index;
+	pdata->line = serial8250_register_8250_port(&uart);
+	if (pdata->line < 0)
 		return -ENODEV;
 
-	pnp_set_drvdata(dev, (void *)((long)line + 1));
+	pnp_set_drvdata(dev, pdata);
 	return 0;
 }
 
 static void fintek_8250_remove(struct pnp_dev *dev)
 {
-	long line = (long)pnp_get_drvdata(dev);
+	struct fintek_8250 *pdata = pnp_get_drvdata(dev);
 
-	if (line)
-		serial8250_unregister_port(line - 1);
+	if (pdata)
+		serial8250_unregister_port(pdata->line);
 }
 
 #ifdef CONFIG_PM
 static int fintek_8250_suspend(struct pnp_dev *dev, pm_message_t state)
 {
-	long line = (long)pnp_get_drvdata(dev);
+	struct fintek_8250 *pdata = pnp_get_drvdata(dev);
 
-	if (!line)
+	if (!pdata)
 		return -ENODEV;
-	serial8250_suspend_port(line - 1);
+	serial8250_suspend_port(pdata->line);
 	return 0;
 }
 
 static int fintek_8250_resume(struct pnp_dev *dev)
 {
-	long line = (long)pnp_get_drvdata(dev);
+	struct fintek_8250 *pdata = pnp_get_drvdata(dev);
 
-	if (!line)
+	if (!pdata)
 		return -ENODEV;
-	serial8250_resume_port(line - 1);
+	serial8250_resume_port(pdata->line);
 	return 0;
 }
 #else

drivers/tty/serial/8250/8250_ingenic.c

@@ -252,7 +252,6 @@ MODULE_DEVICE_TABLE(of, of_match);
 static struct platform_driver ingenic_uart_platform_driver = {
 	.driver = {
 		.name		= "ingenic-uart",
-		.owner		= THIS_MODULE,
 		.of_match_table	= of_match,
 	},
 	.probe			= ingenic_uart_probe,

drivers/tty/serial/8250/8250_omap.c

@@ -16,6 +16,7 @@
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <linux/of.h>
+#include <linux/of_device.h>
 #include <linux/of_gpio.h>
 #include <linux/of_irq.h>
 #include <linux/delay.h>
@@ -32,6 +33,11 @@
 #define UART_ERRATA_i202_MDR1_ACCESS	(1 << 0)
 #define OMAP_UART_WER_HAS_TX_WAKEUP	(1 << 1)
 #define OMAP_DMA_TX_KICK		(1 << 2)
+/*
+ * See Advisory 21 in AM437x errata SPRZ408B, updated April 2015.
+ * The same errata is applicable to AM335x and DRA7x processors too.
+ */
+#define UART_ERRATA_CLOCK_DISABLE	(1 << 3)
 
 #define OMAP_UART_FCR_RX_TRIG		6
 #define OMAP_UART_FCR_TX_TRIG		4
@@ -53,6 +59,12 @@
 #define OMAP_UART_MVR_MAJ_SHIFT		8
 #define OMAP_UART_MVR_MIN_MASK		0x3f
 
+/* SYSC register bitmasks */
+#define OMAP_UART_SYSC_SOFTRESET	(1 << 1)
+
+/* SYSS register bitmasks */
+#define OMAP_UART_SYSS_RESETDONE	(1 << 0)
+
 #define UART_TI752_TLR_TX	0
 #define UART_TI752_TLR_RX	4
 
@@ -100,6 +112,7 @@ struct omap8250_priv {
 	struct work_struct qos_work;
 	struct uart_8250_dma omap8250_dma;
 	spinlock_t rx_dma_lock;
+	bool rx_dma_broken;
 };
 
 static u32 uart_read(struct uart_8250_port *up, u32 reg)
@@ -232,6 +245,15 @@ static void omap8250_update_scr(struct uart_8250_port *up,
 	serial_out(up, UART_OMAP_SCR, priv->scr);
 }
 
+static void omap8250_update_mdr1(struct uart_8250_port *up,
+				 struct omap8250_priv *priv)
+{
+	if (priv->habit & UART_ERRATA_i202_MDR1_ACCESS)
+		omap_8250_mdr1_errataset(up, priv);
+	else
+		serial_out(up, UART_OMAP_MDR1, priv->mdr1);
+}
+
 static void omap8250_restore_regs(struct uart_8250_port *up)
 {
 	struct omap8250_priv *priv = up->port.private_data;
@@ -282,11 +304,9 @@ static void omap8250_restore_regs(struct uart_8250_port *up)
 	serial_out(up, UART_XOFF1, priv->xoff);
 
 	serial_out(up, UART_LCR, up->lcr);
-	/* need mode A for FCR */
-	if (priv->habit & UART_ERRATA_i202_MDR1_ACCESS)
-		omap_8250_mdr1_errataset(up, priv);
-	else
-		serial_out(up, UART_OMAP_MDR1, priv->mdr1);
+
+	omap8250_update_mdr1(up, priv);
+
 	up->port.ops->set_mctrl(&up->port, up->port.mctrl);
 }
 
@@ -428,12 +448,9 @@ static void omap_8250_set_termios(struct uart_port *port,
 		priv->efr |= UART_EFR_CTS;
 	} else	if (up->port.flags & UPF_SOFT_FLOW) {
 		/*
-		 * IXON Flag:
-		 * Enable XON/XOFF flow control on input.
-		 * Receiver compares XON1, XOFF1.
+		 * OMAP rx s/w flow control is borked; the transmitter remains
+		 * stuck off even if rx flow control is subsequently disabled
 		 */
-		if (termios->c_iflag & IXON)
-			priv->efr |= OMAP_UART_SW_RX;
 
 		/*
 		 * IXOFF Flag:
@@ -444,15 +461,6 @@ static void omap_8250_set_termios(struct uart_port *port,
 			up->port.status |= UPSTAT_AUTOXOFF;
 			priv->efr |= OMAP_UART_SW_TX;
 		}
-
-		/*
-		 * IXANY Flag:
-		 * Enable any character to restart output.
-		 * Operation resumes after receiving any
-		 * character after recognition of the XOFF character
-		 */
-		if (termios->c_iflag & IXANY)
-			up->mcr |= UART_MCR_XONANY;
 	}
 	omap8250_restore_regs(up);
 
@@ -530,14 +538,14 @@ static void omap_serial_fill_features_erratas(struct uart_8250_port *up,
 
 	switch (revision) {
 	case OMAP_UART_REV_46:
-		priv->habit = UART_ERRATA_i202_MDR1_ACCESS;
+		priv->habit |= UART_ERRATA_i202_MDR1_ACCESS;
 		break;
 	case OMAP_UART_REV_52:
-		priv->habit = UART_ERRATA_i202_MDR1_ACCESS |
+		priv->habit |= UART_ERRATA_i202_MDR1_ACCESS |
 				OMAP_UART_WER_HAS_TX_WAKEUP;
 		break;
 	case OMAP_UART_REV_63:
-		priv->habit = UART_ERRATA_i202_MDR1_ACCESS |
+		priv->habit |= UART_ERRATA_i202_MDR1_ACCESS |
 			OMAP_UART_WER_HAS_TX_WAKEUP;
 		break;
 	default:
@@ -754,6 +762,7 @@ static void omap_8250_rx_dma_flush(struct uart_8250_port *p)
 	struct omap8250_priv	*priv = p->port.private_data;
 	struct uart_8250_dma	*dma = p->dma;
 	unsigned long		flags;
+	int ret;
 
 	spin_lock_irqsave(&priv->rx_dma_lock, flags);
 
@@ -762,7 +771,9 @@ static void omap_8250_rx_dma_flush(struct uart_8250_port *p)
 		return;
 	}
 
-	dmaengine_pause(dma->rxchan);
+	ret = dmaengine_pause(dma->rxchan);
+	if (WARN_ON_ONCE(ret))
+		priv->rx_dma_broken = true;
 
 	spin_unlock_irqrestore(&priv->rx_dma_lock, flags);
 
@@ -806,6 +817,9 @@ static int omap_8250_rx_dma(struct uart_8250_port *p, unsigned int iir)
 		break;
 	}
 
+	if (priv->rx_dma_broken)
+		return -EINVAL;
+
 	spin_lock_irqsave(&priv->rx_dma_lock, flags);
 
 	if (dma->rx_running)
@@ -1054,6 +1068,20 @@ static int omap8250_no_handle_irq(struct uart_port *port)
 	return 0;
 }
 
+static const u8 am3352_habit = OMAP_DMA_TX_KICK | UART_ERRATA_CLOCK_DISABLE;
+static const u8 am4372_habit = UART_ERRATA_CLOCK_DISABLE;
+
+static const struct of_device_id omap8250_dt_ids[] = {
+	{ .compatible = "ti,omap2-uart" },
+	{ .compatible = "ti,omap3-uart" },
+	{ .compatible = "ti,omap4-uart" },
+	{ .compatible = "ti,am3352-uart", .data = &am3352_habit, },
+	{ .compatible = "ti,am4372-uart", .data = &am4372_habit, },
+	{ .compatible = "ti,dra742-uart", .data = &am4372_habit, },
+	{},
+};
+MODULE_DEVICE_TABLE(of, omap8250_dt_ids);
+
 static int omap8250_probe(struct platform_device *pdev)
 {
 	struct resource *regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -1118,11 +1146,17 @@ static int omap8250_probe(struct platform_device *pdev)
 	up.port.unthrottle = omap_8250_unthrottle;
 
 	if (pdev->dev.of_node) {
+		const struct of_device_id *id;
+
 		ret = of_alias_get_id(pdev->dev.of_node, "serial");
 
 		of_property_read_u32(pdev->dev.of_node, "clock-frequency",
 				     &up.port.uartclk);
 		priv->wakeirq = irq_of_parse_and_map(pdev->dev.of_node, 1);
+
+		id = of_match_device(of_match_ptr(omap8250_dt_ids), &pdev->dev);
+		if (id && id->data)
+			priv->habit |= *(u8 *)id->data;
 	} else {
 		ret = pdev->id;
 	}
@@ -1180,6 +1214,11 @@ static int omap8250_probe(struct platform_device *pdev)
 
 			if (of_machine_is_compatible("ti,am33xx"))
 				priv->habit |= OMAP_DMA_TX_KICK;
+			/*
+			 * pause is currently not supported atleast on omap-sdma
+			 * and edma on most earlier kernels.
+			 */
+			priv->rx_dma_broken = true;
 		}
 	}
 #endif
@@ -1257,17 +1296,46 @@ static int omap8250_lost_context(struct uart_8250_port *up)
 {
 	u32 val;
 
-	val = serial_in(up, UART_OMAP_MDR1);
+	val = serial_in(up, UART_OMAP_SCR);
 	/*
-	 * If we lose context, then MDR1 is set to its reset value which is
-	 * UART_OMAP_MDR1_DISABLE. After set_termios() we set it either to 13x
-	 * or 16x but never to disable again.
+	 * If we lose context, then SCR is set to its reset value of zero.
+	 * After set_termios() we set bit 3 of SCR (TX_EMPTY_CTL_IT) to 1,
+	 * among other bits, to never set the register back to zero again.
 	 */
-	if (val == UART_OMAP_MDR1_DISABLE)
+	if (!val)
 		return 1;
 	return 0;
 }
 
+/* TODO: in future, this should happen via API in drivers/reset/ */
+static int omap8250_soft_reset(struct device *dev)
+{
+	struct omap8250_priv *priv = dev_get_drvdata(dev);
+	struct uart_8250_port *up = serial8250_get_port(priv->line);
+	int timeout = 100;
+	int sysc;
+	int syss;
+
+	sysc = serial_in(up, UART_OMAP_SYSC);
+
+	/* softreset the UART */
+	sysc |= OMAP_UART_SYSC_SOFTRESET;
+	serial_out(up, UART_OMAP_SYSC, sysc);
+
+	/* By experiments, 1us enough for reset complete on AM335x */
+	do {
+		udelay(1);
+		syss = serial_in(up, UART_OMAP_SYSS);
+	} while (--timeout && !(syss & OMAP_UART_SYSS_RESETDONE));
+
+	if (!timeout) {
+		dev_err(dev, "timed out waiting for reset done\n");
+		return -ETIMEDOUT;
+	}
+
+	return 0;
+}
+
 static int omap8250_runtime_suspend(struct device *dev)
 {
 	struct omap8250_priv *priv = dev_get_drvdata(dev);
@@ -1285,7 +1353,18 @@ static int omap8250_runtime_suspend(struct device *dev)
 			return -EBUSY;
 	}
 
-	if (up->dma)
+	if (priv->habit & UART_ERRATA_CLOCK_DISABLE) {
+		int ret;
+
+		ret = omap8250_soft_reset(dev);
+		if (ret)
+			return ret;
+
+		/* Restore to UART mode after reset (for wakeup) */
+		omap8250_update_mdr1(up, priv);
+	}
+
+	if (up->dma && up->dma->rxchan)
 		omap_8250_rx_dma(up, UART_IIR_RX_TIMEOUT);
 
 	priv->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
@@ -1310,7 +1389,7 @@ static int omap8250_runtime_resume(struct device *dev)
 	if (loss_cntx)
 		omap8250_restore_regs(up);
 
-	if (up->dma)
+	if (up->dma && up->dma->rxchan)
 		omap_8250_rx_dma(up, 0);
 
 	priv->latency = priv->calc_latency;
@@ -1367,14 +1446,6 @@ static const struct dev_pm_ops omap8250_dev_pm_ops = {
 	.complete       = omap8250_complete,
 };
 
-static const struct of_device_id omap8250_dt_ids[] = {
-	{ .compatible = "ti,omap2-uart" },
-	{ .compatible = "ti,omap3-uart" },
-	{ .compatible = "ti,omap4-uart" },
-	{},
-};
-MODULE_DEVICE_TABLE(of, omap8250_dt_ids);
-
 static struct platform_driver omap8250_platform_driver = {
 	.driver = {
 		.name		= "omap8250",

drivers/tty/serial/8250/8250_pci.c

@@ -1417,6 +1417,10 @@ byt_set_termios(struct uart_port *p, struct ktermios *termios,
 	reg |= BYT_PRV_CLK_EN | BYT_PRV_CLK_UPDATE;
 	writel(reg, p->membase + BYT_PRV_CLK);
 
+	p->status &= ~UPSTAT_AUTOCTS;
+	if (termios->c_cflag & CRTSCTS)
+		p->status |= UPSTAT_AUTOCTS;
+
 	serial8250_do_set_termios(p, termios, old);
 }
 
@@ -1685,11 +1689,65 @@ pci_brcm_trumanage_setup(struct serial_private *priv,
 	return ret;
 }
 
+/* RTS will control by MCR if this bit is 0 */
+#define FINTEK_RTS_CONTROL_BY_HW	BIT(4)
+/* only worked with FINTEK_RTS_CONTROL_BY_HW on */
+#define FINTEK_RTS_INVERT		BIT(5)
+
+/* We should do proper H/W transceiver setting before change to RS485 mode */
+static int pci_fintek_rs485_config(struct uart_port *port,
+			       struct serial_rs485 *rs485)
+{
+	u8 setting;
+	u8 *index = (u8 *) port->private_data;
+	struct pci_dev *pci_dev = container_of(port->dev, struct pci_dev,
+						dev);
+
+	pci_read_config_byte(pci_dev, 0x40 + 8 * *index + 7, &setting);
+
+	if (!rs485)
+		rs485 = &port->rs485;
+	else if (rs485->flags & SER_RS485_ENABLED)
+		memset(rs485->padding, 0, sizeof(rs485->padding));
+	else
+		memset(rs485, 0, sizeof(*rs485));
+
+	/* F81504/508/512 not support RTS delay before or after send */
+	rs485->flags &= SER_RS485_ENABLED | SER_RS485_RTS_ON_SEND;
+
+	if (rs485->flags & SER_RS485_ENABLED) {
+		/* Enable RTS H/W control mode */
+		setting |= FINTEK_RTS_CONTROL_BY_HW;
+
+		if (rs485->flags & SER_RS485_RTS_ON_SEND) {
+			/* RTS driving high on TX */
+			setting &= ~FINTEK_RTS_INVERT;
+		} else {
+			/* RTS driving low on TX */
+			setting |= FINTEK_RTS_INVERT;
+		}
+
+		rs485->delay_rts_after_send = 0;
+		rs485->delay_rts_before_send = 0;
+	} else {
+		/* Disable RTS H/W control mode */
+		setting &= ~(FINTEK_RTS_CONTROL_BY_HW | FINTEK_RTS_INVERT);
+	}
+
+	pci_write_config_byte(pci_dev, 0x40 + 8 * *index + 7, setting);
+
+	if (rs485 != &port->rs485)
+		port->rs485 = *rs485;
+
+	return 0;
+}
+
 static int pci_fintek_setup(struct serial_private *priv,
 			    const struct pciserial_board *board,
 			    struct uart_8250_port *port, int idx)
 {
 	struct pci_dev *pdev = priv->dev;
+	u8 *data;
 	u8 config_base;
 	u16 iobase;
 
@@ -1702,6 +1760,15 @@ static int pci_fintek_setup(struct serial_private *priv,
 
 	port->port.iotype = UPIO_PORT;
 	port->port.iobase = iobase;
+	port->port.rs485_config = pci_fintek_rs485_config;
+
+	data = devm_kzalloc(&pdev->dev, sizeof(u8), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	/* preserve index in PCI configuration space */
+	*data = idx;
+	port->port.private_data = data;
 
 	return 0;
 }
@@ -1712,6 +1779,8 @@ static int pci_fintek_init(struct pci_dev *dev)
 	u32 max_port, i;
 	u32 bar_data[3];
 	u8 config_base;
+	struct serial_private *priv = pci_get_drvdata(dev);
+	struct uart_8250_port *port;
 
 	switch (dev->device) {
 	case 0x1104: /* 4 ports */
@@ -1752,6 +1821,19 @@ static int pci_fintek_init(struct pci_dev *dev)
 				(u8)((iobase & 0xff00) >> 8));
 
 		pci_write_config_byte(dev, config_base + 0x06, dev->irq);
+
+		if (priv) {
+			/* re-apply RS232/485 mode when
+			 * pciserial_resume_ports()
+			 */
+			port = serial8250_get_port(priv->line[i]);
+			pci_fintek_rs485_config(&port->port, NULL);
+		} else {
+			/* First init without port data
+			 * force init to RS232 Mode
+			 */
+			pci_write_config_byte(dev, config_base + 0x07, 0x01);
+		}
 	}
 
 	return max_port;
@@ -2017,6 +2099,12 @@ pci_wch_ch38x_setup(struct serial_private *priv,
 #define PCIE_DEVICE_ID_WCH_CH382_2S1P	0x3250
 #define PCIE_DEVICE_ID_WCH_CH384_4S	0x3470
 
+#define PCI_VENDOR_ID_PERICOM			0x12D8
+#define PCI_DEVICE_ID_PERICOM_PI7C9X7951	0x7951
+#define PCI_DEVICE_ID_PERICOM_PI7C9X7952	0x7952
+#define PCI_DEVICE_ID_PERICOM_PI7C9X7954	0x7954
+#define PCI_DEVICE_ID_PERICOM_PI7C9X7958	0x7958
+
 /* Unknown vendors/cards - this should not be in linux/pci_ids.h */
 #define PCI_SUBDEVICE_ID_UNKNOWN_0x1584	0x1584
 #define PCI_SUBDEVICE_ID_UNKNOWN_0x1588	0x1588
@@ -2331,27 +2419,12 @@ static struct pci_serial_quirk pci_serial_quirks[] __refdata = {
 	 * Pericom
 	 */
 	{
-		.vendor		= 0x12d8,
-		.device		= 0x7952,
-		.subvendor	= PCI_ANY_ID,
-		.subdevice	= PCI_ANY_ID,
-		.setup		= pci_pericom_setup,
-	},
-	{
-		.vendor		= 0x12d8,
-		.device		= 0x7954,
-		.subvendor	= PCI_ANY_ID,
-		.subdevice	= PCI_ANY_ID,
-		.setup		= pci_pericom_setup,
-	},
-	{
-		.vendor		= 0x12d8,
-		.device		= 0x7958,
-		.subvendor	= PCI_ANY_ID,
-		.subdevice	= PCI_ANY_ID,
-		.setup		= pci_pericom_setup,
+		.vendor         = PCI_VENDOR_ID_PERICOM,
+		.device         = PCI_ANY_ID,
+		.subvendor      = PCI_ANY_ID,
+		.subdevice      = PCI_ANY_ID,
+		.setup          = pci_pericom_setup,
 	},
-
 	/*
 	 * PLX
 	 */
@@ -3056,6 +3129,10 @@ enum pci_board_num_t {
 	pbn_fintek_8,
 	pbn_fintek_12,
 	pbn_wch384_4,
+	pbn_pericom_PI7C9X7951,
+	pbn_pericom_PI7C9X7952,
+	pbn_pericom_PI7C9X7954,
+	pbn_pericom_PI7C9X7958,
 };
 
 /*
@@ -3881,7 +3958,6 @@ static struct pciserial_board pci_boards[] = {
 		.base_baud	= 115200,
 		.first_offset	= 0x40,
 	},
-
 	[pbn_wch384_4] = {
 		.flags		= FL_BASE0,
 		.num_ports	= 4,
@@ -3889,6 +3965,33 @@ static struct pciserial_board pci_boards[] = {
 		.uart_offset    = 8,
 		.first_offset   = 0xC0,
 	},
+	/*
+	 * Pericom PI7C9X795[1248] Uno/Dual/Quad/Octal UART
+	 */
+	[pbn_pericom_PI7C9X7951] = {
+		.flags          = FL_BASE0,
+		.num_ports      = 1,
+		.base_baud      = 921600,
+		.uart_offset	= 0x8,
+	},
+	[pbn_pericom_PI7C9X7952] = {
+		.flags          = FL_BASE0,
+		.num_ports      = 2,
+		.base_baud      = 921600,
+		.uart_offset	= 0x8,
+	},
+	[pbn_pericom_PI7C9X7954] = {
+		.flags          = FL_BASE0,
+		.num_ports      = 4,
+		.base_baud      = 921600,
+		.uart_offset	= 0x8,
+	},
+	[pbn_pericom_PI7C9X7958] = {
+		.flags          = FL_BASE0,
+		.num_ports      = 8,
+		.base_baud      = 921600,
+		.uart_offset	= 0x8,
+	},
 };
 
 static const struct pci_device_id blacklist[] = {
@@ -5153,6 +5256,25 @@ static struct pci_device_id serial_pci_tbl[] = {
 		PCI_ANY_ID, PCI_ANY_ID,
 		0,
 		0, pbn_exar_XR17V8358 },
+	/*
+	 * Pericom PI7C9X795[1248] Uno/Dual/Quad/Octal UART
+	 */
+	{   PCI_VENDOR_ID_PERICOM, PCI_DEVICE_ID_PERICOM_PI7C9X7951,
+		PCI_ANY_ID, PCI_ANY_ID,
+		0,
+		0, pbn_pericom_PI7C9X7951 },
+	{   PCI_VENDOR_ID_PERICOM, PCI_DEVICE_ID_PERICOM_PI7C9X7952,
+		PCI_ANY_ID, PCI_ANY_ID,
+		0,
+		0, pbn_pericom_PI7C9X7952 },
+	{   PCI_VENDOR_ID_PERICOM, PCI_DEVICE_ID_PERICOM_PI7C9X7954,
+		PCI_ANY_ID, PCI_ANY_ID,
+		0,
+		0, pbn_pericom_PI7C9X7954 },
+	{   PCI_VENDOR_ID_PERICOM, PCI_DEVICE_ID_PERICOM_PI7C9X7958,
+		PCI_ANY_ID, PCI_ANY_ID,
+		0,
+		0, pbn_pericom_PI7C9X7958 },
 	/*
 	 * Topic TP560 Data/Fax/Voice 56k modem (reported by Evan Clarke)
 	 */

drivers/tty/serial/8250/8250_pnp.c

@@ -41,6 +41,12 @@ static const struct pnp_device_id pnp_dev_table[] = {
 	{	"AEI1240",		0	},
 	/* Rockwell 56K ACF II Fax+Data+Voice Modem */
 	{	"AKY1021",		0 /*SPCI_FL_NO_SHIRQ*/	},
+	/*
+	 * ALi Fast Infrared Controller
+	 * Native driver (ali-ircc) is broken so at least
+	 * it can be used with irtty-sir.
+	 */
+	{	"ALI5123",		0	},
 	/* AZT3005 PnP SOUND DEVICE */
 	{	"AZT4001",		0	},
 	/* Best Data Products Inc. Smart One 336F PnP Modem */
@@ -364,6 +370,11 @@ static const struct pnp_device_id pnp_dev_table[] = {
 	/* Winbond CIR port, should not be probed. We should keep track
 	   of it to prevent the legacy serial driver from probing it */
 	{	"WEC1022",		CIR_PORT	},
+	/*
+	 * SMSC IrCC SIR/FIR port, should not be probed by serial driver
+	 * as well so its own driver can bind to it.
+	 */
+	{	"SMCF010",		CIR_PORT	},
 	{	"",			0	}
 };
 

drivers/tty/serial/8250/8250_port.c

@@ -0,0 +1,2912 @@
+/*
+ *  Base port operations for 8250/16550-type serial ports
+ *
+ *  Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
+ *  Split from 8250_core.c, Copyright (C) 2001 Russell King.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * A note about mapbase / membase
+ *
+ *  mapbase is the physical address of the IO port.
+ *  membase is an 'ioremapped' cookie.
+ */
+
+#if defined(CONFIG_SERIAL_8250_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
+#define SUPPORT_SYSRQ
+#endif
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/ioport.h>
+#include <linux/init.h>
+#include <linux/console.h>
+#include <linux/sysrq.h>
+#include <linux/delay.h>
+#include <linux/platform_device.h>
+#include <linux/tty.h>
+#include <linux/ratelimit.h>
+#include <linux/tty_flip.h>
+#include <linux/serial.h>
+#include <linux/serial_8250.h>
+#include <linux/nmi.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/pm_runtime.h>
+
+#include <asm/io.h>
+#include <asm/irq.h>
+
+#include "8250.h"
+
+/*
+ * Debugging.
+ */
+#if 0
+#define DEBUG_AUTOCONF(fmt...)	printk(fmt)
+#else
+#define DEBUG_AUTOCONF(fmt...)	do { } while (0)
+#endif
+
+#define BOTH_EMPTY 	(UART_LSR_TEMT | UART_LSR_THRE)
+
+/*
+ * Here we define the default xmit fifo size used for each type of UART.
+ */
+static const struct serial8250_config uart_config[] = {
+	[PORT_UNKNOWN] = {
+		.name		= "unknown",
+		.fifo_size	= 1,
+		.tx_loadsz	= 1,
+	},
+	[PORT_8250] = {
+		.name		= "8250",
+		.fifo_size	= 1,
+		.tx_loadsz	= 1,
+	},
+	[PORT_16450] = {
+		.name		= "16450",
+		.fifo_size	= 1,
+		.tx_loadsz	= 1,
+	},
+	[PORT_16550] = {
+		.name		= "16550",
+		.fifo_size	= 1,
+		.tx_loadsz	= 1,
+	},
+	[PORT_16550A] = {
+		.name		= "16550A",
+		.fifo_size	= 16,
+		.tx_loadsz	= 16,
+		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
+		.rxtrig_bytes	= {1, 4, 8, 14},
+		.flags		= UART_CAP_FIFO,
+	},
+	[PORT_CIRRUS] = {
+		.name		= "Cirrus",
+		.fifo_size	= 1,
+		.tx_loadsz	= 1,
+	},
+	[PORT_16650] = {
+		.name		= "ST16650",
+		.fifo_size	= 1,
+		.tx_loadsz	= 1,
+		.flags		= UART_CAP_FIFO | UART_CAP_EFR | UART_CAP_SLEEP,
+	},
+	[PORT_16650V2] = {
+		.name		= "ST16650V2",
+		.fifo_size	= 32,
+		.tx_loadsz	= 16,
+		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_01 |
+				  UART_FCR_T_TRIG_00,
+		.rxtrig_bytes	= {8, 16, 24, 28},
+		.flags		= UART_CAP_FIFO | UART_CAP_EFR | UART_CAP_SLEEP,
+	},
+	[PORT_16750] = {
+		.name		= "TI16750",
+		.fifo_size	= 64,
+		.tx_loadsz	= 64,
+		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10 |
+				  UART_FCR7_64BYTE,
+		.rxtrig_bytes	= {1, 16, 32, 56},
+		.flags		= UART_CAP_FIFO | UART_CAP_SLEEP | UART_CAP_AFE,
+	},
+	[PORT_STARTECH] = {
+		.name		= "Startech",
+		.fifo_size	= 1,
+		.tx_loadsz	= 1,
+	},
+	[PORT_16C950] = {
+		.name		= "16C950/954",
+		.fifo_size	= 128,
+		.tx_loadsz	= 128,
+		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
+		/* UART_CAP_EFR breaks billionon CF bluetooth card. */
+		.flags		= UART_CAP_FIFO | UART_CAP_SLEEP,
+	},
+	[PORT_16654] = {
+		.name		= "ST16654",
+		.fifo_size	= 64,
+		.tx_loadsz	= 32,
+		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_01 |
+				  UART_FCR_T_TRIG_10,
+		.rxtrig_bytes	= {8, 16, 56, 60},
+		.flags		= UART_CAP_FIFO | UART_CAP_EFR | UART_CAP_SLEEP,
+	},
+	[PORT_16850] = {
+		.name		= "XR16850",
+		.fifo_size	= 128,
+		.tx_loadsz	= 128,
+		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
+		.flags		= UART_CAP_FIFO | UART_CAP_EFR | UART_CAP_SLEEP,
+	},
+	[PORT_RSA] = {
+		.name		= "RSA",
+		.fifo_size	= 2048,
+		.tx_loadsz	= 2048,
+		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_11,
+		.flags		= UART_CAP_FIFO,
+	},
+	[PORT_NS16550A] = {
+		.name		= "NS16550A",
+		.fifo_size	= 16,
+		.tx_loadsz	= 16,
+		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
+		.flags		= UART_CAP_FIFO | UART_NATSEMI,
+	},
+	[PORT_XSCALE] = {
+		.name		= "XScale",
+		.fifo_size	= 32,
+		.tx_loadsz	= 32,
+		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
+		.flags		= UART_CAP_FIFO | UART_CAP_UUE | UART_CAP_RTOIE,
+	},
+	[PORT_OCTEON] = {
+		.name		= "OCTEON",
+		.fifo_size	= 64,
+		.tx_loadsz	= 64,
+		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
+		.flags		= UART_CAP_FIFO,
+	},
+	[PORT_AR7] = {
+		.name		= "AR7",
+		.fifo_size	= 16,
+		.tx_loadsz	= 16,
+		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_00,
+		.flags		= UART_CAP_FIFO | UART_CAP_AFE,
+	},
+	[PORT_U6_16550A] = {
+		.name		= "U6_16550A",
+		.fifo_size	= 64,
+		.tx_loadsz	= 64,
+		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
+		.flags		= UART_CAP_FIFO | UART_CAP_AFE,
+	},
+	[PORT_TEGRA] = {
+		.name		= "Tegra",
+		.fifo_size	= 32,
+		.tx_loadsz	= 8,
+		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_01 |
+				  UART_FCR_T_TRIG_01,
+		.rxtrig_bytes	= {1, 4, 8, 14},
+		.flags		= UART_CAP_FIFO | UART_CAP_RTOIE,
+	},
+	[PORT_XR17D15X] = {
+		.name		= "XR17D15X",
+		.fifo_size	= 64,
+		.tx_loadsz	= 64,
+		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
+		.flags		= UART_CAP_FIFO | UART_CAP_AFE | UART_CAP_EFR |
+				  UART_CAP_SLEEP,
+	},
+	[PORT_XR17V35X] = {
+		.name		= "XR17V35X",
+		.fifo_size	= 256,
+		.tx_loadsz	= 256,
+		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_11 |
+				  UART_FCR_T_TRIG_11,
+		.flags		= UART_CAP_FIFO | UART_CAP_AFE | UART_CAP_EFR |
+				  UART_CAP_SLEEP,
+	},
+	[PORT_LPC3220] = {
+		.name		= "LPC3220",
+		.fifo_size	= 64,
+		.tx_loadsz	= 32,
+		.fcr		= UART_FCR_DMA_SELECT | UART_FCR_ENABLE_FIFO |
+				  UART_FCR_R_TRIG_00 | UART_FCR_T_TRIG_00,
+		.flags		= UART_CAP_FIFO,
+	},
+	[PORT_BRCM_TRUMANAGE] = {
+		.name		= "TruManage",
+		.fifo_size	= 1,
+		.tx_loadsz	= 1024,
+		.flags		= UART_CAP_HFIFO,
+	},
+	[PORT_8250_CIR] = {
+		.name		= "CIR port"
+	},
+	[PORT_ALTR_16550_F32] = {
+		.name		= "Altera 16550 FIFO32",
+		.fifo_size	= 32,
+		.tx_loadsz	= 32,
+		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
+		.flags		= UART_CAP_FIFO | UART_CAP_AFE,
+	},
+	[PORT_ALTR_16550_F64] = {
+		.name		= "Altera 16550 FIFO64",
+		.fifo_size	= 64,
+		.tx_loadsz	= 64,
+		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
+		.flags		= UART_CAP_FIFO | UART_CAP_AFE,
+	},
+	[PORT_ALTR_16550_F128] = {
+		.name		= "Altera 16550 FIFO128",
+		.fifo_size	= 128,
+		.tx_loadsz	= 128,
+		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
+		.flags		= UART_CAP_FIFO | UART_CAP_AFE,
+	},
+/* tx_loadsz is set to 63-bytes instead of 64-bytes to implement
+workaround of errata A-008006 which states that tx_loadsz should  be
+configured less than Maximum supported fifo bytes */
+	[PORT_16550A_FSL64] = {
+		.name		= "16550A_FSL64",
+		.fifo_size	= 64,
+		.tx_loadsz	= 63,
+		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10 |
+				  UART_FCR7_64BYTE,
+		.flags		= UART_CAP_FIFO,
+	},
+};
+
+/* Uart divisor latch read */
+static int default_serial_dl_read(struct uart_8250_port *up)
+{
+	return serial_in(up, UART_DLL) | serial_in(up, UART_DLM) << 8;
+}
+
+/* Uart divisor latch write */
+static void default_serial_dl_write(struct uart_8250_port *up, int value)
+{
+	serial_out(up, UART_DLL, value & 0xff);
+	serial_out(up, UART_DLM, value >> 8 & 0xff);
+}
+
+#if defined(CONFIG_MIPS_ALCHEMY) || defined(CONFIG_SERIAL_8250_RT288X)
+
+/* Au1x00/RT288x UART hardware has a weird register layout */
+static const s8 au_io_in_map[8] = {
+	 0,	/* UART_RX  */
+	 2,	/* UART_IER */
+	 3,	/* UART_IIR */
+	 5,	/* UART_LCR */
+	 6,	/* UART_MCR */
+	 7,	/* UART_LSR */
+	 8,	/* UART_MSR */
+	-1,	/* UART_SCR (unmapped) */
+};
+
+static const s8 au_io_out_map[8] = {
+	 1,	/* UART_TX  */
+	 2,	/* UART_IER */
+	 4,	/* UART_FCR */
+	 5,	/* UART_LCR */
+	 6,	/* UART_MCR */
+	-1,	/* UART_LSR (unmapped) */
+	-1,	/* UART_MSR (unmapped) */
+	-1,	/* UART_SCR (unmapped) */
+};
+
+static unsigned int au_serial_in(struct uart_port *p, int offset)
+{
+	if (offset >= ARRAY_SIZE(au_io_in_map))
+		return UINT_MAX;
+	offset = au_io_in_map[offset];
+	if (offset < 0)
+		return UINT_MAX;
+	return __raw_readl(p->membase + (offset << p->regshift));
+}
+
+static void au_serial_out(struct uart_port *p, int offset, int value)
+{
+	if (offset >= ARRAY_SIZE(au_io_out_map))
+		return;
+	offset = au_io_out_map[offset];
+	if (offset < 0)
+		return;
+	__raw_writel(value, p->membase + (offset << p->regshift));
+}
+
+/* Au1x00 haven't got a standard divisor latch */
+static int au_serial_dl_read(struct uart_8250_port *up)
+{
+	return __raw_readl(up->port.membase + 0x28);
+}
+
+static void au_serial_dl_write(struct uart_8250_port *up, int value)
+{
+	__raw_writel(value, up->port.membase + 0x28);
+}
+
+#endif
+
+static unsigned int hub6_serial_in(struct uart_port *p, int offset)
+{
+	offset = offset << p->regshift;
+	outb(p->hub6 - 1 + offset, p->iobase);
+	return inb(p->iobase + 1);
+}
+
+static void hub6_serial_out(struct uart_port *p, int offset, int value)
+{
+	offset = offset << p->regshift;
+	outb(p->hub6 - 1 + offset, p->iobase);
+	outb(value, p->iobase + 1);
+}
+
+static unsigned int mem_serial_in(struct uart_port *p, int offset)
+{
+	offset = offset << p->regshift;
+	return readb(p->membase + offset);
+}
+
+static void mem_serial_out(struct uart_port *p, int offset, int value)
+{
+	offset = offset << p->regshift;
+	writeb(value, p->membase + offset);
+}
+
+static void mem32_serial_out(struct uart_port *p, int offset, int value)
+{
+	offset = offset << p->regshift;
+	writel(value, p->membase + offset);
+}
+
+static unsigned int mem32_serial_in(struct uart_port *p, int offset)
+{
+	offset = offset << p->regshift;
+	return readl(p->membase + offset);
+}
+
+static void mem32be_serial_out(struct uart_port *p, int offset, int value)
+{
+	offset = offset << p->regshift;
+	iowrite32be(value, p->membase + offset);
+}
+
+static unsigned int mem32be_serial_in(struct uart_port *p, int offset)
+{
+	offset = offset << p->regshift;
+	return ioread32be(p->membase + offset);
+}
+
+static unsigned int io_serial_in(struct uart_port *p, int offset)
+{
+	offset = offset << p->regshift;
+	return inb(p->iobase + offset);
+}
+
+static void io_serial_out(struct uart_port *p, int offset, int value)
+{
+	offset = offset << p->regshift;
+	outb(value, p->iobase + offset);
+}
+
+static int serial8250_default_handle_irq(struct uart_port *port);
+static int exar_handle_irq(struct uart_port *port);
+
+static void set_io_from_upio(struct uart_port *p)
+{
+	struct uart_8250_port *up = up_to_u8250p(p);
+
+	up->dl_read = default_serial_dl_read;
+	up->dl_write = default_serial_dl_write;
+
+	switch (p->iotype) {
+	case UPIO_HUB6:
+		p->serial_in = hub6_serial_in;
+		p->serial_out = hub6_serial_out;
+		break;
+
+	case UPIO_MEM:
+		p->serial_in = mem_serial_in;
+		p->serial_out = mem_serial_out;
+		break;
+
+	case UPIO_MEM32:
+		p->serial_in = mem32_serial_in;
+		p->serial_out = mem32_serial_out;
+		break;
+
+	case UPIO_MEM32BE:
+		p->serial_in = mem32be_serial_in;
+		p->serial_out = mem32be_serial_out;
+		break;
+
+#if defined(CONFIG_MIPS_ALCHEMY) || defined(CONFIG_SERIAL_8250_RT288X)
+	case UPIO_AU:
+		p->serial_in = au_serial_in;
+		p->serial_out = au_serial_out;
+		up->dl_read = au_serial_dl_read;
+		up->dl_write = au_serial_dl_write;
+		break;
+#endif
+
+	default:
+		p->serial_in = io_serial_in;
+		p->serial_out = io_serial_out;
+		break;
+	}
+	/* Remember loaded iotype */
+	up->cur_iotype = p->iotype;
+	p->handle_irq = serial8250_default_handle_irq;
+}
+
+static void
+serial_port_out_sync(struct uart_port *p, int offset, int value)
+{
+	switch (p->iotype) {
+	case UPIO_MEM:
+	case UPIO_MEM32:
+	case UPIO_MEM32BE:
+	case UPIO_AU:
+		p->serial_out(p, offset, value);
+		p->serial_in(p, UART_LCR);	/* safe, no side-effects */
+		break;
+	default:
+		p->serial_out(p, offset, value);
+	}
+}
+
+/*
+ * For the 16C950
+ */
+static void serial_icr_write(struct uart_8250_port *up, int offset, int value)
+{
+	serial_out(up, UART_SCR, offset);
+	serial_out(up, UART_ICR, value);
+}
+
+static unsigned int serial_icr_read(struct uart_8250_port *up, int offset)
+{
+	unsigned int value;
+
+	serial_icr_write(up, UART_ACR, up->acr | UART_ACR_ICRRD);
+	serial_out(up, UART_SCR, offset);
+	value = serial_in(up, UART_ICR);
+	serial_icr_write(up, UART_ACR, up->acr);
+
+	return value;
+}
+
+/*
+ * FIFO support.
+ */
+static void serial8250_clear_fifos(struct uart_8250_port *p)
+{
+	if (p->capabilities & UART_CAP_FIFO) {
+		serial_out(p, UART_FCR, UART_FCR_ENABLE_FIFO);
+		serial_out(p, UART_FCR, UART_FCR_ENABLE_FIFO |
+			       UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
+		serial_out(p, UART_FCR, 0);
+	}
+}
+
+void serial8250_clear_and_reinit_fifos(struct uart_8250_port *p)
+{
+	serial8250_clear_fifos(p);
+	serial_out(p, UART_FCR, p->fcr);
+}
+EXPORT_SYMBOL_GPL(serial8250_clear_and_reinit_fifos);
+
+void serial8250_rpm_get(struct uart_8250_port *p)
+{
+	if (!(p->capabilities & UART_CAP_RPM))
+		return;
+	pm_runtime_get_sync(p->port.dev);
+}
+EXPORT_SYMBOL_GPL(serial8250_rpm_get);
+
+void serial8250_rpm_put(struct uart_8250_port *p)
+{
+	if (!(p->capabilities & UART_CAP_RPM))
+		return;
+	pm_runtime_mark_last_busy(p->port.dev);
+	pm_runtime_put_autosuspend(p->port.dev);
+}
+EXPORT_SYMBOL_GPL(serial8250_rpm_put);
+
+/*
+ * These two wrappers ensure that enable_runtime_pm_tx() can be called more than
+ * once and disable_runtime_pm_tx() will still disable RPM because the fifo is
+ * empty and the HW can idle again.
+ */
+static void serial8250_rpm_get_tx(struct uart_8250_port *p)
+{
+	unsigned char rpm_active;
+
+	if (!(p->capabilities & UART_CAP_RPM))
+		return;
+
+	rpm_active = xchg(&p->rpm_tx_active, 1);
+	if (rpm_active)
+		return;
+	pm_runtime_get_sync(p->port.dev);
+}
+
+static void serial8250_rpm_put_tx(struct uart_8250_port *p)
+{
+	unsigned char rpm_active;
+
+	if (!(p->capabilities & UART_CAP_RPM))
+		return;
+
+	rpm_active = xchg(&p->rpm_tx_active, 0);
+	if (!rpm_active)
+		return;
+	pm_runtime_mark_last_busy(p->port.dev);
+	pm_runtime_put_autosuspend(p->port.dev);
+}
+
+/*
+ * IER sleep support.  UARTs which have EFRs need the "extended
+ * capability" bit enabled.  Note that on XR16C850s, we need to
+ * reset LCR to write to IER.
+ */
+static void serial8250_set_sleep(struct uart_8250_port *p, int sleep)
+{
+	unsigned char lcr = 0, efr = 0;
+	/*
+	 * Exar UARTs have a SLEEP register that enables or disables
+	 * each UART to enter sleep mode separately.  On the XR17V35x the
+	 * register is accessible to each UART at the UART_EXAR_SLEEP
+	 * offset but the UART channel may only write to the corresponding
+	 * bit.
+	 */
+	serial8250_rpm_get(p);
+	if ((p->port.type == PORT_XR17V35X) ||
+	   (p->port.type == PORT_XR17D15X)) {
+		serial_out(p, UART_EXAR_SLEEP, sleep ? 0xff : 0);
+		goto out;
+	}
+
+	if (p->capabilities & UART_CAP_SLEEP) {
+		if (p->capabilities & UART_CAP_EFR) {
+			lcr = serial_in(p, UART_LCR);
+			efr = serial_in(p, UART_EFR);
+			serial_out(p, UART_LCR, UART_LCR_CONF_MODE_B);
+			serial_out(p, UART_EFR, UART_EFR_ECB);
+			serial_out(p, UART_LCR, 0);
+		}
+		serial_out(p, UART_IER, sleep ? UART_IERX_SLEEP : 0);
+		if (p->capabilities & UART_CAP_EFR) {
+			serial_out(p, UART_LCR, UART_LCR_CONF_MODE_B);
+			serial_out(p, UART_EFR, efr);
+			serial_out(p, UART_LCR, lcr);
+		}
+	}
+out:
+	serial8250_rpm_put(p);
+}
+
+#ifdef CONFIG_SERIAL_8250_RSA
+/*
+ * Attempts to turn on the RSA FIFO.  Returns zero on failure.
+ * We set the port uart clock rate if we succeed.
+ */
+static int __enable_rsa(struct uart_8250_port *up)
+{
+	unsigned char mode;
+	int result;
+
+	mode = serial_in(up, UART_RSA_MSR);
+	result = mode & UART_RSA_MSR_FIFO;
+
+	if (!result) {
+		serial_out(up, UART_RSA_MSR, mode | UART_RSA_MSR_FIFO);
+		mode = serial_in(up, UART_RSA_MSR);
+		result = mode & UART_RSA_MSR_FIFO;
+	}
+
+	if (result)
+		up->port.uartclk = SERIAL_RSA_BAUD_BASE * 16;
+
+	return result;
+}
+
+static void enable_rsa(struct uart_8250_port *up)
+{
+	if (up->port.type == PORT_RSA) {
+		if (up->port.uartclk != SERIAL_RSA_BAUD_BASE * 16) {
+			spin_lock_irq(&up->port.lock);
+			__enable_rsa(up);
+			spin_unlock_irq(&up->port.lock);
+		}
+		if (up->port.uartclk == SERIAL_RSA_BAUD_BASE * 16)
+			serial_out(up, UART_RSA_FRR, 0);
+	}
+}
+
+/*
+ * Attempts to turn off the RSA FIFO.  Returns zero on failure.
+ * It is unknown why interrupts were disabled in here.  However,
+ * the caller is expected to preserve this behaviour by grabbing
+ * the spinlock before calling this function.
+ */
+static void disable_rsa(struct uart_8250_port *up)
+{
+	unsigned char mode;
+	int result;
+
+	if (up->port.type == PORT_RSA &&
+	    up->port.uartclk == SERIAL_RSA_BAUD_BASE * 16) {
+		spin_lock_irq(&up->port.lock);
+
+		mode = serial_in(up, UART_RSA_MSR);
+		result = !(mode & UART_RSA_MSR_FIFO);
+
+		if (!result) {
+			serial_out(up, UART_RSA_MSR, mode & ~UART_RSA_MSR_FIFO);
+			mode = serial_in(up, UART_RSA_MSR);
+			result = !(mode & UART_RSA_MSR_FIFO);
+		}
+
+		if (result)
+			up->port.uartclk = SERIAL_RSA_BAUD_BASE_LO * 16;
+		spin_unlock_irq(&up->port.lock);
+	}
+}
+#endif /* CONFIG_SERIAL_8250_RSA */
+
+/*
+ * This is a quickie test to see how big the FIFO is.
+ * It doesn't work at all the time, more's the pity.
+ */
+static int size_fifo(struct uart_8250_port *up)
+{
+	unsigned char old_fcr, old_mcr, old_lcr;
+	unsigned short old_dl;
+	int count;
+
+	old_lcr = serial_in(up, UART_LCR);
+	serial_out(up, UART_LCR, 0);
+	old_fcr = serial_in(up, UART_FCR);
+	old_mcr = serial_in(up, UART_MCR);
+	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
+		    UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
+	serial_out(up, UART_MCR, UART_MCR_LOOP);
+	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
+	old_dl = serial_dl_read(up);
+	serial_dl_write(up, 0x0001);
+	serial_out(up, UART_LCR, 0x03);
+	for (count = 0; count < 256; count++)
+		serial_out(up, UART_TX, count);
+	mdelay(20);/* FIXME - schedule_timeout */
+	for (count = 0; (serial_in(up, UART_LSR) & UART_LSR_DR) &&
+	     (count < 256); count++)
+		serial_in(up, UART_RX);
+	serial_out(up, UART_FCR, old_fcr);
+	serial_out(up, UART_MCR, old_mcr);
+	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
+	serial_dl_write(up, old_dl);
+	serial_out(up, UART_LCR, old_lcr);
+
+	return count;
+}
+
+/*
+ * Read UART ID using the divisor method - set DLL and DLM to zero
+ * and the revision will be in DLL and device type in DLM.  We
+ * preserve the device state across this.
+ */
+static unsigned int autoconfig_read_divisor_id(struct uart_8250_port *p)
+{
+	unsigned char old_dll, old_dlm, old_lcr;
+	unsigned int id;
+
+	old_lcr = serial_in(p, UART_LCR);
+	serial_out(p, UART_LCR, UART_LCR_CONF_MODE_A);
+
+	old_dll = serial_in(p, UART_DLL);
+	old_dlm = serial_in(p, UART_DLM);
+
+	serial_out(p, UART_DLL, 0);
+	serial_out(p, UART_DLM, 0);
+
+	id = serial_in(p, UART_DLL) | serial_in(p, UART_DLM) << 8;
+
+	serial_out(p, UART_DLL, old_dll);
+	serial_out(p, UART_DLM, old_dlm);
+	serial_out(p, UART_LCR, old_lcr);
+
+	return id;
+}
+
+/*
+ * This is a helper routine to autodetect StarTech/Exar/Oxsemi UART's.
+ * When this function is called we know it is at least a StarTech
+ * 16650 V2, but it might be one of several StarTech UARTs, or one of
+ * its clones.  (We treat the broken original StarTech 16650 V1 as a
+ * 16550, and why not?  Startech doesn't seem to even acknowledge its
+ * existence.)
+ *
+ * What evil have men's minds wrought...
+ */
+static void autoconfig_has_efr(struct uart_8250_port *up)
+{
+	unsigned int id1, id2, id3, rev;
+
+	/*
+	 * Everything with an EFR has SLEEP
+	 */
+	up->capabilities |= UART_CAP_EFR | UART_CAP_SLEEP;
+
+	/*
+	 * First we check to see if it's an Oxford Semiconductor UART.
+	 *
+	 * If we have to do this here because some non-National
+	 * Semiconductor clone chips lock up if you try writing to the
+	 * LSR register (which serial_icr_read does)
+	 */
+
+	/*
+	 * Check for Oxford Semiconductor 16C950.
+	 *
+	 * EFR [4] must be set else this test fails.
+	 *
+	 * This shouldn't be necessary, but Mike Hudson (Exoray@isys.ca)
+	 * claims that it's needed for 952 dual UART's (which are not
+	 * recommended for new designs).
+	 */
+	up->acr = 0;
+	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
+	serial_out(up, UART_EFR, UART_EFR_ECB);
+	serial_out(up, UART_LCR, 0x00);
+	id1 = serial_icr_read(up, UART_ID1);
+	id2 = serial_icr_read(up, UART_ID2);
+	id3 = serial_icr_read(up, UART_ID3);
+	rev = serial_icr_read(up, UART_REV);
+
+	DEBUG_AUTOCONF("950id=%02x:%02x:%02x:%02x ", id1, id2, id3, rev);
+
+	if (id1 == 0x16 && id2 == 0xC9 &&
+	    (id3 == 0x50 || id3 == 0x52 || id3 == 0x54)) {
+		up->port.type = PORT_16C950;
+
+		/*
+		 * Enable work around for the Oxford Semiconductor 952 rev B
+		 * chip which causes it to seriously miscalculate baud rates
+		 * when DLL is 0.
+		 */
+		if (id3 == 0x52 && rev == 0x01)
+			up->bugs |= UART_BUG_QUOT;
+		return;
+	}
+
+	/*
+	 * We check for a XR16C850 by setting DLL and DLM to 0, and then
+	 * reading back DLL and DLM.  The chip type depends on the DLM
+	 * value read back:
+	 *  0x10 - XR16C850 and the DLL contains the chip revision.
+	 *  0x12 - XR16C2850.
+	 *  0x14 - XR16C854.
+	 */
+	id1 = autoconfig_read_divisor_id(up);
+	DEBUG_AUTOCONF("850id=%04x ", id1);
+
+	id2 = id1 >> 8;
+	if (id2 == 0x10 || id2 == 0x12 || id2 == 0x14) {
+		up->port.type = PORT_16850;
+		return;
+	}
+
+	/*
+	 * It wasn't an XR16C850.
+	 *
+	 * We distinguish between the '654 and the '650 by counting
+	 * how many bytes are in the FIFO.  I'm using this for now,
+	 * since that's the technique that was sent to me in the
+	 * serial driver update, but I'm not convinced this works.
+	 * I've had problems doing this in the past.  -TYT
+	 */
+	if (size_fifo(up) == 64)
+		up->port.type = PORT_16654;
+	else
+		up->port.type = PORT_16650V2;
+}
+
+/*
+ * We detected a chip without a FIFO.  Only two fall into
+ * this category - the original 8250 and the 16450.  The
+ * 16450 has a scratch register (accessible with LCR=0)
+ */
+static void autoconfig_8250(struct uart_8250_port *up)
+{
+	unsigned char scratch, status1, status2;
+
+	up->port.type = PORT_8250;
+
+	scratch = serial_in(up, UART_SCR);
+	serial_out(up, UART_SCR, 0xa5);
+	status1 = serial_in(up, UART_SCR);
+	serial_out(up, UART_SCR, 0x5a);
+	status2 = serial_in(up, UART_SCR);
+	serial_out(up, UART_SCR, scratch);
+
+	if (status1 == 0xa5 && status2 == 0x5a)
+		up->port.type = PORT_16450;
+}
+
+static int broken_efr(struct uart_8250_port *up)
+{
+	/*
+	 * Exar ST16C2550 "A2" devices incorrectly detect as
+	 * having an EFR, and report an ID of 0x0201.  See
+	 * http://linux.derkeiler.com/Mailing-Lists/Kernel/2004-11/4812.html
+	 */
+	if (autoconfig_read_divisor_id(up) == 0x0201 && size_fifo(up) == 16)
+		return 1;
+
+	return 0;
+}
+
+/*
+ * We know that the chip has FIFOs.  Does it have an EFR?  The
+ * EFR is located in the same register position as the IIR and
+ * we know the top two bits of the IIR are currently set.  The
+ * EFR should contain zero.  Try to read the EFR.
+ */
+static void autoconfig_16550a(struct uart_8250_port *up)
+{
+	unsigned char status1, status2;
+	unsigned int iersave;
+
+	up->port.type = PORT_16550A;
+	up->capabilities |= UART_CAP_FIFO;
+
+	/*
+	 * XR17V35x UARTs have an extra divisor register, DLD
+	 * that gets enabled with when DLAB is set which will
+	 * cause the device to incorrectly match and assign
+	 * port type to PORT_16650.  The EFR for this UART is
+	 * found at offset 0x09. Instead check the Deice ID (DVID)
+	 * register for a 2, 4 or 8 port UART.
+	 */
+	if (up->port.flags & UPF_EXAR_EFR) {
+		status1 = serial_in(up, UART_EXAR_DVID);
+		if (status1 == 0x82 || status1 == 0x84 || status1 == 0x88) {
+			DEBUG_AUTOCONF("Exar XR17V35x ");
+			up->port.type = PORT_XR17V35X;
+			up->capabilities |= UART_CAP_AFE | UART_CAP_EFR |
+						UART_CAP_SLEEP;
+
+			return;
+		}
+
+	}
+
+	/*
+	 * Check for presence of the EFR when DLAB is set.
+	 * Only ST16C650V1 UARTs pass this test.
+	 */
+	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
+	if (serial_in(up, UART_EFR) == 0) {
+		serial_out(up, UART_EFR, 0xA8);
+		if (serial_in(up, UART_EFR) != 0) {
+			DEBUG_AUTOCONF("EFRv1 ");
+			up->port.type = PORT_16650;
+			up->capabilities |= UART_CAP_EFR | UART_CAP_SLEEP;
+		} else {
+			serial_out(up, UART_LCR, 0);
+			serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
+				   UART_FCR7_64BYTE);
+			status1 = serial_in(up, UART_IIR) >> 5;
+			serial_out(up, UART_FCR, 0);
+			serial_out(up, UART_LCR, 0);
+
+			if (status1 == 7)
+				up->port.type = PORT_16550A_FSL64;
+			else
+				DEBUG_AUTOCONF("Motorola 8xxx DUART ");
+		}
+		serial_out(up, UART_EFR, 0);
+		return;
+	}
+
+	/*
+	 * Maybe it requires 0xbf to be written to the LCR.
+	 * (other ST16C650V2 UARTs, TI16C752A, etc)
+	 */
+	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
+	if (serial_in(up, UART_EFR) == 0 && !broken_efr(up)) {
+		DEBUG_AUTOCONF("EFRv2 ");
+		autoconfig_has_efr(up);
+		return;
+	}
+
+	/*
+	 * Check for a National Semiconductor SuperIO chip.
+	 * Attempt to switch to bank 2, read the value of the LOOP bit
+	 * from EXCR1. Switch back to bank 0, change it in MCR. Then
+	 * switch back to bank 2, read it from EXCR1 again and check
+	 * it's changed. If so, set baud_base in EXCR2 to 921600. -- dwmw2
+	 */
+	serial_out(up, UART_LCR, 0);
+	status1 = serial_in(up, UART_MCR);
+	serial_out(up, UART_LCR, 0xE0);
+	status2 = serial_in(up, 0x02); /* EXCR1 */
+
+	if (!((status2 ^ status1) & UART_MCR_LOOP)) {
+		serial_out(up, UART_LCR, 0);
+		serial_out(up, UART_MCR, status1 ^ UART_MCR_LOOP);
+		serial_out(up, UART_LCR, 0xE0);
+		status2 = serial_in(up, 0x02); /* EXCR1 */
+		serial_out(up, UART_LCR, 0);
+		serial_out(up, UART_MCR, status1);
+
+		if ((status2 ^ status1) & UART_MCR_LOOP) {
+			unsigned short quot;
+
+			serial_out(up, UART_LCR, 0xE0);
+
+			quot = serial_dl_read(up);
+			quot <<= 3;
+
+			if (ns16550a_goto_highspeed(up))
+				serial_dl_write(up, quot);
+
+			serial_out(up, UART_LCR, 0);
+
+			up->port.uartclk = 921600*16;
+			up->port.type = PORT_NS16550A;
+			up->capabilities |= UART_NATSEMI;
+			return;
+		}
+	}
+
+	/*
+	 * No EFR.  Try to detect a TI16750, which only sets bit 5 of
+	 * the IIR when 64 byte FIFO mode is enabled when DLAB is set.
+	 * Try setting it with and without DLAB set.  Cheap clones
+	 * set bit 5 without DLAB set.
+	 */
+	serial_out(up, UART_LCR, 0);
+	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR7_64BYTE);
+	status1 = serial_in(up, UART_IIR) >> 5;
+	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
+	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
+	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR7_64BYTE);
+	status2 = serial_in(up, UART_IIR) >> 5;
+	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
+	serial_out(up, UART_LCR, 0);
+
+	DEBUG_AUTOCONF("iir1=%d iir2=%d ", status1, status2);
+
+	if (status1 == 6 && status2 == 7) {
+		up->port.type = PORT_16750;
+		up->capabilities |= UART_CAP_AFE | UART_CAP_SLEEP;
+		return;
+	}
+
+	/*
+	 * Try writing and reading the UART_IER_UUE bit (b6).
+	 * If it works, this is probably one of the Xscale platform's
+	 * internal UARTs.
+	 * We're going to explicitly set the UUE bit to 0 before
+	 * trying to write and read a 1 just to make sure it's not
+	 * already a 1 and maybe locked there before we even start start.
+	 */
+	iersave = serial_in(up, UART_IER);
+	serial_out(up, UART_IER, iersave & ~UART_IER_UUE);
+	if (!(serial_in(up, UART_IER) & UART_IER_UUE)) {
+		/*
+		 * OK it's in a known zero state, try writing and reading
+		 * without disturbing the current state of the other bits.
+		 */
+		serial_out(up, UART_IER, iersave | UART_IER_UUE);
+		if (serial_in(up, UART_IER) & UART_IER_UUE) {
+			/*
+			 * It's an Xscale.
+			 * We'll leave the UART_IER_UUE bit set to 1 (enabled).
+			 */
+			DEBUG_AUTOCONF("Xscale ");
+			up->port.type = PORT_XSCALE;
+			up->capabilities |= UART_CAP_UUE | UART_CAP_RTOIE;
+			return;
+		}
+	} else {
+		/*
+		 * If we got here we couldn't force the IER_UUE bit to 0.
+		 * Log it and continue.
+		 */
+		DEBUG_AUTOCONF("Couldn't force IER_UUE to 0 ");
+	}
+	serial_out(up, UART_IER, iersave);
+
+	/*
+	 * Exar uarts have EFR in a weird location
+	 */
+	if (up->port.flags & UPF_EXAR_EFR) {
+		DEBUG_AUTOCONF("Exar XR17D15x ");
+		up->port.type = PORT_XR17D15X;
+		up->capabilities |= UART_CAP_AFE | UART_CAP_EFR |
+				    UART_CAP_SLEEP;
+
+		return;
+	}
+
+	/*
+	 * We distinguish between 16550A and U6 16550A by counting
+	 * how many bytes are in the FIFO.
+	 */
+	if (up->port.type == PORT_16550A && size_fifo(up) == 64) {
+		up->port.type = PORT_U6_16550A;
+		up->capabilities |= UART_CAP_AFE;
+	}
+}
+
+/*
+ * This routine is called by rs_init() to initialize a specific serial
+ * port.  It determines what type of UART chip this serial port is
+ * using: 8250, 16450, 16550, 16550A.  The important question is
+ * whether or not this UART is a 16550A or not, since this will
+ * determine whether or not we can use its FIFO features or not.
+ */
+static void autoconfig(struct uart_8250_port *up)
+{
+	unsigned char status1, scratch, scratch2, scratch3;
+	unsigned char save_lcr, save_mcr;
+	struct uart_port *port = &up->port;
+	unsigned long flags;
+	unsigned int old_capabilities;
+
+	if (!port->iobase && !port->mapbase && !port->membase)
+		return;
+
+	DEBUG_AUTOCONF("ttyS%d: autoconf (0x%04lx, 0x%p): ",
+		       serial_index(port), port->iobase, port->membase);
+
+	/*
+	 * We really do need global IRQs disabled here - we're going to
+	 * be frobbing the chips IRQ enable register to see if it exists.
+	 */
+	spin_lock_irqsave(&port->lock, flags);
+
+	up->capabilities = 0;
+	up->bugs = 0;
+
+	if (!(port->flags & UPF_BUGGY_UART)) {
+		/*
+		 * Do a simple existence test first; if we fail this,
+		 * there's no point trying anything else.
+		 *
+		 * 0x80 is used as a nonsense port to prevent against
+		 * false positives due to ISA bus float.  The
+		 * assumption is that 0x80 is a non-existent port;
+		 * which should be safe since include/asm/io.h also
+		 * makes this assumption.
+		 *
+		 * Note: this is safe as long as MCR bit 4 is clear
+		 * and the device is in "PC" mode.
+		 */
+		scratch = serial_in(up, UART_IER);
+		serial_out(up, UART_IER, 0);
+#ifdef __i386__
+		outb(0xff, 0x080);
+#endif
+		/*
+		 * Mask out IER[7:4] bits for test as some UARTs (e.g. TL
+		 * 16C754B) allow only to modify them if an EFR bit is set.
+		 */
+		scratch2 = serial_in(up, UART_IER) & 0x0f;
+		serial_out(up, UART_IER, 0x0F);
+#ifdef __i386__
+		outb(0, 0x080);
+#endif
+		scratch3 = serial_in(up, UART_IER) & 0x0f;
+		serial_out(up, UART_IER, scratch);
+		if (scratch2 != 0 || scratch3 != 0x0F) {
+			/*
+			 * We failed; there's nothing here
+			 */
+			spin_unlock_irqrestore(&port->lock, flags);
+			DEBUG_AUTOCONF("IER test failed (%02x, %02x) ",
+				       scratch2, scratch3);
+			goto out;
+		}
+	}
+
+	save_mcr = serial_in(up, UART_MCR);
+	save_lcr = serial_in(up, UART_LCR);
+
+	/*
+	 * Check to see if a UART is really there.  Certain broken
+	 * internal modems based on the Rockwell chipset fail this
+	 * test, because they apparently don't implement the loopback
+	 * test mode.  So this test is skipped on the COM 1 through
+	 * COM 4 ports.  This *should* be safe, since no board
+	 * manufacturer would be stupid enough to design a board
+	 * that conflicts with COM 1-4 --- we hope!
+	 */
+	if (!(port->flags & UPF_SKIP_TEST)) {
+		serial_out(up, UART_MCR, UART_MCR_LOOP | 0x0A);
+		status1 = serial_in(up, UART_MSR) & 0xF0;
+		serial_out(up, UART_MCR, save_mcr);
+		if (status1 != 0x90) {
+			spin_unlock_irqrestore(&port->lock, flags);
+			DEBUG_AUTOCONF("LOOP test failed (%02x) ",
+				       status1);
+			goto out;
+		}
+	}
+
+	/*
+	 * We're pretty sure there's a port here.  Lets find out what
+	 * type of port it is.  The IIR top two bits allows us to find
+	 * out if it's 8250 or 16450, 16550, 16550A or later.  This
+	 * determines what we test for next.
+	 *
+	 * We also initialise the EFR (if any) to zero for later.  The
+	 * EFR occupies the same register location as the FCR and IIR.
+	 */
+	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
+	serial_out(up, UART_EFR, 0);
+	serial_out(up, UART_LCR, 0);
+
+	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
+	scratch = serial_in(up, UART_IIR) >> 6;
+
+	switch (scratch) {
+	case 0:
+		autoconfig_8250(up);
+		break;
+	case 1:
+		port->type = PORT_UNKNOWN;
+		break;
+	case 2:
+		port->type = PORT_16550;
+		break;
+	case 3:
+		autoconfig_16550a(up);
+		break;
+	}
+
+#ifdef CONFIG_SERIAL_8250_RSA
+	/*
+	 * Only probe for RSA ports if we got the region.
+	 */
+	if (port->type == PORT_16550A && up->probe & UART_PROBE_RSA &&
+	    __enable_rsa(up))
+		port->type = PORT_RSA;
+#endif
+
+	serial_out(up, UART_LCR, save_lcr);
+
+	port->fifosize = uart_config[up->port.type].fifo_size;
+	old_capabilities = up->capabilities;
+	up->capabilities = uart_config[port->type].flags;
+	up->tx_loadsz = uart_config[port->type].tx_loadsz;
+
+	if (port->type == PORT_UNKNOWN)
+		goto out_lock;
+
+	/*
+	 * Reset the UART.
+	 */
+#ifdef CONFIG_SERIAL_8250_RSA
+	if (port->type == PORT_RSA)
+		serial_out(up, UART_RSA_FRR, 0);
+#endif
+	serial_out(up, UART_MCR, save_mcr);
+	serial8250_clear_fifos(up);
+	serial_in(up, UART_RX);
+	if (up->capabilities & UART_CAP_UUE)
+		serial_out(up, UART_IER, UART_IER_UUE);
+	else
+		serial_out(up, UART_IER, 0);
+
+out_lock:
+	spin_unlock_irqrestore(&port->lock, flags);
+	if (up->capabilities != old_capabilities) {
+		printk(KERN_WARNING
+		       "ttyS%d: detected caps %08x should be %08x\n",
+		       serial_index(port), old_capabilities,
+		       up->capabilities);
+	}
+out:
+	DEBUG_AUTOCONF("iir=%d ", scratch);
+	DEBUG_AUTOCONF("type=%s\n", uart_config[port->type].name);
+}
+
+static void autoconfig_irq(struct uart_8250_port *up)
+{
+	struct uart_port *port = &up->port;
+	unsigned char save_mcr, save_ier;
+	unsigned char save_ICP = 0;
+	unsigned int ICP = 0;
+	unsigned long irqs;
+	int irq;
+
+	if (port->flags & UPF_FOURPORT) {
+		ICP = (port->iobase & 0xfe0) | 0x1f;
+		save_ICP = inb_p(ICP);
+		outb_p(0x80, ICP);
+		inb_p(ICP);
+	}
+
+	/* forget possible initially masked and pending IRQ */
+	probe_irq_off(probe_irq_on());
+	save_mcr = serial_in(up, UART_MCR);
+	save_ier = serial_in(up, UART_IER);
+	serial_out(up, UART_MCR, UART_MCR_OUT1 | UART_MCR_OUT2);
+
+	irqs = probe_irq_on();
+	serial_out(up, UART_MCR, 0);
+	udelay(10);
+	if (port->flags & UPF_FOURPORT) {
+		serial_out(up, UART_MCR,
+			    UART_MCR_DTR | UART_MCR_RTS);
+	} else {
+		serial_out(up, UART_MCR,
+			    UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2);
+	}
+	serial_out(up, UART_IER, 0x0f);	/* enable all intrs */
+	serial_in(up, UART_LSR);
+	serial_in(up, UART_RX);
+	serial_in(up, UART_IIR);
+	serial_in(up, UART_MSR);
+	serial_out(up, UART_TX, 0xFF);
+	udelay(20);
+	irq = probe_irq_off(irqs);
+
+	serial_out(up, UART_MCR, save_mcr);
+	serial_out(up, UART_IER, save_ier);
+
+	if (port->flags & UPF_FOURPORT)
+		outb_p(save_ICP, ICP);
+
+	port->irq = (irq > 0) ? irq : 0;
+}
+
+static inline void __stop_tx(struct uart_8250_port *p)
+{
+	if (p->ier & UART_IER_THRI) {
+		p->ier &= ~UART_IER_THRI;
+		serial_out(p, UART_IER, p->ier);
+		serial8250_rpm_put_tx(p);
+	}
+}
+
+static void serial8250_stop_tx(struct uart_port *port)
+{
+	struct uart_8250_port *up = up_to_u8250p(port);
+
+	serial8250_rpm_get(up);
+	__stop_tx(up);
+
+	/*
+	 * We really want to stop the transmitter from sending.
+	 */
+	if (port->type == PORT_16C950) {
+		up->acr |= UART_ACR_TXDIS;
+		serial_icr_write(up, UART_ACR, up->acr);
+	}
+	serial8250_rpm_put(up);
+}
+
+static void serial8250_start_tx(struct uart_port *port)
+{
+	struct uart_8250_port *up = up_to_u8250p(port);
+
+	serial8250_rpm_get_tx(up);
+
+	if (up->dma && !up->dma->tx_dma(up))
+		return;
+
+	if (!(up->ier & UART_IER_THRI)) {
+		up->ier |= UART_IER_THRI;
+		serial_port_out(port, UART_IER, up->ier);
+
+		if (up->bugs & UART_BUG_TXEN) {
+			unsigned char lsr;
+			lsr = serial_in(up, UART_LSR);
+			up->lsr_saved_flags |= lsr & LSR_SAVE_FLAGS;
+			if (lsr & UART_LSR_THRE)
+				serial8250_tx_chars(up);
+		}
+	}
+
+	/*
+	 * Re-enable the transmitter if we disabled it.
+	 */
+	if (port->type == PORT_16C950 && up->acr & UART_ACR_TXDIS) {
+		up->acr &= ~UART_ACR_TXDIS;
+		serial_icr_write(up, UART_ACR, up->acr);
+	}
+}
+
+static void serial8250_throttle(struct uart_port *port)
+{
+	port->throttle(port);
+}
+
+static void serial8250_unthrottle(struct uart_port *port)
+{
+	port->unthrottle(port);
+}
+
+static void serial8250_stop_rx(struct uart_port *port)
+{
+	struct uart_8250_port *up = up_to_u8250p(port);
+
+	serial8250_rpm_get(up);
+
+	up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
+	up->port.read_status_mask &= ~UART_LSR_DR;
+	serial_port_out(port, UART_IER, up->ier);
+
+	serial8250_rpm_put(up);
+}
+
+static void serial8250_disable_ms(struct uart_port *port)
+{
+	struct uart_8250_port *up =
+		container_of(port, struct uart_8250_port, port);
+
+	/* no MSR capabilities */
+	if (up->bugs & UART_BUG_NOMSR)
+		return;
+
+	up->ier &= ~UART_IER_MSI;
+	serial_port_out(port, UART_IER, up->ier);
+}
+
+static void serial8250_enable_ms(struct uart_port *port)
+{
+	struct uart_8250_port *up = up_to_u8250p(port);
+
+	/* no MSR capabilities */
+	if (up->bugs & UART_BUG_NOMSR)
+		return;
+
+	up->ier |= UART_IER_MSI;
+
+	serial8250_rpm_get(up);
+	serial_port_out(port, UART_IER, up->ier);
+	serial8250_rpm_put(up);
+}
+
+/*
+ * serial8250_rx_chars: processes according to the passed in LSR
+ * value, and returns the remaining LSR bits not handled
+ * by this Rx routine.
+ */
+unsigned char
+serial8250_rx_chars(struct uart_8250_port *up, unsigned char lsr)
+{
+	struct uart_port *port = &up->port;
+	unsigned char ch;
+	int max_count = 256;
+	char flag;
+
+	do {
+		if (likely(lsr & UART_LSR_DR))
+			ch = serial_in(up, UART_RX);
+		else
+			/*
+			 * Intel 82571 has a Serial Over Lan device that will
+			 * set UART_LSR_BI without setting UART_LSR_DR when
+			 * it receives a break. To avoid reading from the
+			 * receive buffer without UART_LSR_DR bit set, we
+			 * just force the read character to be 0
+			 */
+			ch = 0;
+
+		flag = TTY_NORMAL;
+		port->icount.rx++;
+
+		lsr |= up->lsr_saved_flags;
+		up->lsr_saved_flags = 0;
+
+		if (unlikely(lsr & UART_LSR_BRK_ERROR_BITS)) {
+			if (lsr & UART_LSR_BI) {
+				lsr &= ~(UART_LSR_FE | UART_LSR_PE);
+				port->icount.brk++;
+				/*
+				 * We do the SysRQ and SAK checking
+				 * here because otherwise the break
+				 * may get masked by ignore_status_mask
+				 * or read_status_mask.
+				 */
+				if (uart_handle_break(port))
+					goto ignore_char;
+			} else if (lsr & UART_LSR_PE)
+				port->icount.parity++;
+			else if (lsr & UART_LSR_FE)
+				port->icount.frame++;
+			if (lsr & UART_LSR_OE)
+				port->icount.overrun++;
+
+			/*
+			 * Mask off conditions which should be ignored.
+			 */
+			lsr &= port->read_status_mask;
+
+			if (lsr & UART_LSR_BI) {
+				DEBUG_INTR("handling break....");
+				flag = TTY_BREAK;
+			} else if (lsr & UART_LSR_PE)
+				flag = TTY_PARITY;
+			else if (lsr & UART_LSR_FE)
+				flag = TTY_FRAME;
+		}
+		if (uart_handle_sysrq_char(port, ch))
+			goto ignore_char;
+
+		uart_insert_char(port, lsr, UART_LSR_OE, ch, flag);
+
+ignore_char:
+		lsr = serial_in(up, UART_LSR);
+	} while ((lsr & (UART_LSR_DR | UART_LSR_BI)) && (--max_count > 0));
+	spin_unlock(&port->lock);
+	tty_flip_buffer_push(&port->state->port);
+	spin_lock(&port->lock);
+	return lsr;
+}
+EXPORT_SYMBOL_GPL(serial8250_rx_chars);
+
+void serial8250_tx_chars(struct uart_8250_port *up)
+{
+	struct uart_port *port = &up->port;
+	struct circ_buf *xmit = &port->state->xmit;
+	int count;
+
+	if (port->x_char) {
+		serial_out(up, UART_TX, port->x_char);
+		port->icount.tx++;
+		port->x_char = 0;
+		return;
+	}
+	if (uart_tx_stopped(port)) {
+		serial8250_stop_tx(port);
+		return;
+	}
+	if (uart_circ_empty(xmit)) {
+		__stop_tx(up);
+		return;
+	}
+
+	count = up->tx_loadsz;
+	do {
+		serial_out(up, UART_TX, xmit->buf[xmit->tail]);
+		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+		port->icount.tx++;
+		if (uart_circ_empty(xmit))
+			break;
+		if (up->capabilities & UART_CAP_HFIFO) {
+			if ((serial_port_in(port, UART_LSR) & BOTH_EMPTY) !=
+			    BOTH_EMPTY)
+				break;
+		}
+	} while (--count > 0);
+
+	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+		uart_write_wakeup(port);
+
+	DEBUG_INTR("THRE...");
+
+	/*
+	 * With RPM enabled, we have to wait until the FIFO is empty before the
+	 * HW can go idle. So we get here once again with empty FIFO and disable
+	 * the interrupt and RPM in __stop_tx()
+	 */
+	if (uart_circ_empty(xmit) && !(up->capabilities & UART_CAP_RPM))
+		__stop_tx(up);
+}
+EXPORT_SYMBOL_GPL(serial8250_tx_chars);
+
+/* Caller holds uart port lock */
+unsigned int serial8250_modem_status(struct uart_8250_port *up)
+{
+	struct uart_port *port = &up->port;
+	unsigned int status = serial_in(up, UART_MSR);
+
+	status |= up->msr_saved_flags;
+	up->msr_saved_flags = 0;
+	if (status & UART_MSR_ANY_DELTA && up->ier & UART_IER_MSI &&
+	    port->state != NULL) {
+		if (status & UART_MSR_TERI)
+			port->icount.rng++;
+		if (status & UART_MSR_DDSR)
+			port->icount.dsr++;
+		if (status & UART_MSR_DDCD)
+			uart_handle_dcd_change(port, status & UART_MSR_DCD);
+		if (status & UART_MSR_DCTS)
+			uart_handle_cts_change(port, status & UART_MSR_CTS);
+
+		wake_up_interruptible(&port->state->port.delta_msr_wait);
+	}
+
+	return status;
+}
+EXPORT_SYMBOL_GPL(serial8250_modem_status);
+
+/*
+ * This handles the interrupt from one port.
+ */
+int serial8250_handle_irq(struct uart_port *port, unsigned int iir)
+{
+	unsigned char status;
+	unsigned long flags;
+	struct uart_8250_port *up = up_to_u8250p(port);
+	int dma_err = 0;
+
+	if (iir & UART_IIR_NO_INT)
+		return 0;
+
+	spin_lock_irqsave(&port->lock, flags);
+
+	status = serial_port_in(port, UART_LSR);
+
+	DEBUG_INTR("status = %x...", status);
+
+	if (status & (UART_LSR_DR | UART_LSR_BI)) {
+		if (up->dma)
+			dma_err = up->dma->rx_dma(up, iir);
+
+		if (!up->dma || dma_err)
+			status = serial8250_rx_chars(up, status);
+	}
+	serial8250_modem_status(up);
+	if ((!up->dma || (up->dma && up->dma->tx_err)) &&
+	    (status & UART_LSR_THRE))
+		serial8250_tx_chars(up);
+
+	spin_unlock_irqrestore(&port->lock, flags);
+	return 1;
+}
+EXPORT_SYMBOL_GPL(serial8250_handle_irq);
+
+static int serial8250_default_handle_irq(struct uart_port *port)
+{
+	struct uart_8250_port *up = up_to_u8250p(port);
+	unsigned int iir;
+	int ret;
+
+	serial8250_rpm_get(up);
+
+	iir = serial_port_in(port, UART_IIR);
+	ret = serial8250_handle_irq(port, iir);
+
+	serial8250_rpm_put(up);
+	return ret;
+}
+
+/*
+ * These Exar UARTs have an extra interrupt indicator that could
+ * fire for a few unimplemented interrupts.  One of which is a
+ * wakeup event when coming out of sleep.  Put this here just
+ * to be on the safe side that these interrupts don't go unhandled.
+ */
+static int exar_handle_irq(struct uart_port *port)
+{
+	unsigned char int0, int1, int2, int3;
+	unsigned int iir = serial_port_in(port, UART_IIR);
+	int ret;
+
+	ret = serial8250_handle_irq(port, iir);
+
+	if ((port->type == PORT_XR17V35X) ||
+	   (port->type == PORT_XR17D15X)) {
+		int0 = serial_port_in(port, 0x80);
+		int1 = serial_port_in(port, 0x81);
+		int2 = serial_port_in(port, 0x82);
+		int3 = serial_port_in(port, 0x83);
+	}
+
+	return ret;
+}
+
+static unsigned int serial8250_tx_empty(struct uart_port *port)
+{
+	struct uart_8250_port *up = up_to_u8250p(port);
+	unsigned long flags;
+	unsigned int lsr;
+
+	serial8250_rpm_get(up);
+
+	spin_lock_irqsave(&port->lock, flags);
+	lsr = serial_port_in(port, UART_LSR);
+	up->lsr_saved_flags |= lsr & LSR_SAVE_FLAGS;
+	spin_unlock_irqrestore(&port->lock, flags);
+
+	serial8250_rpm_put(up);
+
+	return (lsr & BOTH_EMPTY) == BOTH_EMPTY ? TIOCSER_TEMT : 0;
+}
+
+static unsigned int serial8250_get_mctrl(struct uart_port *port)
+{
+	struct uart_8250_port *up = up_to_u8250p(port);
+	unsigned int status;
+	unsigned int ret;
+
+	serial8250_rpm_get(up);
+	status = serial8250_modem_status(up);
+	serial8250_rpm_put(up);
+
+	ret = 0;
+	if (status & UART_MSR_DCD)
+		ret |= TIOCM_CAR;
+	if (status & UART_MSR_RI)
+		ret |= TIOCM_RNG;
+	if (status & UART_MSR_DSR)
+		ret |= TIOCM_DSR;
+	if (status & UART_MSR_CTS)
+		ret |= TIOCM_CTS;
+	return ret;
+}
+
+void serial8250_do_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+	struct uart_8250_port *up = up_to_u8250p(port);
+	unsigned char mcr = 0;
+
+	if (mctrl & TIOCM_RTS)
+		mcr |= UART_MCR_RTS;
+	if (mctrl & TIOCM_DTR)
+		mcr |= UART_MCR_DTR;
+	if (mctrl & TIOCM_OUT1)
+		mcr |= UART_MCR_OUT1;
+	if (mctrl & TIOCM_OUT2)
+		mcr |= UART_MCR_OUT2;
+	if (mctrl & TIOCM_LOOP)
+		mcr |= UART_MCR_LOOP;
+
+	mcr = (mcr & up->mcr_mask) | up->mcr_force | up->mcr;
+
+	serial_port_out(port, UART_MCR, mcr);
+}
+EXPORT_SYMBOL_GPL(serial8250_do_set_mctrl);
+
+static void serial8250_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+	if (port->set_mctrl)
+		port->set_mctrl(port, mctrl);
+	else
+		serial8250_do_set_mctrl(port, mctrl);
+}
+
+static void serial8250_break_ctl(struct uart_port *port, int break_state)
+{
+	struct uart_8250_port *up = up_to_u8250p(port);
+	unsigned long flags;
+
+	serial8250_rpm_get(up);
+	spin_lock_irqsave(&port->lock, flags);
+	if (break_state == -1)
+		up->lcr |= UART_LCR_SBC;
+	else
+		up->lcr &= ~UART_LCR_SBC;
+	serial_port_out(port, UART_LCR, up->lcr);
+	spin_unlock_irqrestore(&port->lock, flags);
+	serial8250_rpm_put(up);
+}
+
+/*
+ *	Wait for transmitter & holding register to empty
+ */
+static void wait_for_xmitr(struct uart_8250_port *up, int bits)
+{
+	unsigned int status, tmout = 10000;
+
+	/* Wait up to 10ms for the character(s) to be sent. */
+	for (;;) {
+		status = serial_in(up, UART_LSR);
+
+		up->lsr_saved_flags |= status & LSR_SAVE_FLAGS;
+
+		if ((status & bits) == bits)
+			break;
+		if (--tmout == 0)
+			break;
+		udelay(1);
+	}
+
+	/* Wait up to 1s for flow control if necessary */
+	if (up->port.flags & UPF_CONS_FLOW) {
+		unsigned int tmout;
+		for (tmout = 1000000; tmout; tmout--) {
+			unsigned int msr = serial_in(up, UART_MSR);
+			up->msr_saved_flags |= msr & MSR_SAVE_FLAGS;
+			if (msr & UART_MSR_CTS)
+				break;
+			udelay(1);
+			touch_nmi_watchdog();
+		}
+	}
+}
+
+#ifdef CONFIG_CONSOLE_POLL
+/*
+ * Console polling routines for writing and reading from the uart while
+ * in an interrupt or debug context.
+ */
+
+static int serial8250_get_poll_char(struct uart_port *port)
+{
+	struct uart_8250_port *up = up_to_u8250p(port);
+	unsigned char lsr;
+	int status;
+
+	serial8250_rpm_get(up);
+
+	lsr = serial_port_in(port, UART_LSR);
+
+	if (!(lsr & UART_LSR_DR)) {
+		status = NO_POLL_CHAR;
+		goto out;
+	}
+
+	status = serial_port_in(port, UART_RX);
+out:
+	serial8250_rpm_put(up);
+	return status;
+}
+
+
+static void serial8250_put_poll_char(struct uart_port *port,
+			 unsigned char c)
+{
+	unsigned int ier;
+	struct uart_8250_port *up = up_to_u8250p(port);
+
+	serial8250_rpm_get(up);
+	/*
+	 *	First save the IER then disable the interrupts
+	 */
+	ier = serial_port_in(port, UART_IER);
+	if (up->capabilities & UART_CAP_UUE)
+		serial_port_out(port, UART_IER, UART_IER_UUE);
+	else
+		serial_port_out(port, UART_IER, 0);
+
+	wait_for_xmitr(up, BOTH_EMPTY);
+	/*
+	 *	Send the character out.
+	 */
+	serial_port_out(port, UART_TX, c);
+
+	/*
+	 *	Finally, wait for transmitter to become empty
+	 *	and restore the IER
+	 */
+	wait_for_xmitr(up, BOTH_EMPTY);
+	serial_port_out(port, UART_IER, ier);
+	serial8250_rpm_put(up);
+}
+
+#endif /* CONFIG_CONSOLE_POLL */
+
+int serial8250_do_startup(struct uart_port *port)
+{
+	struct uart_8250_port *up = up_to_u8250p(port);
+	unsigned long flags;
+	unsigned char lsr, iir;
+	int retval;
+
+	if (port->type == PORT_8250_CIR)
+		return -ENODEV;
+
+	if (!port->fifosize)
+		port->fifosize = uart_config[port->type].fifo_size;
+	if (!up->tx_loadsz)
+		up->tx_loadsz = uart_config[port->type].tx_loadsz;
+	if (!up->capabilities)
+		up->capabilities = uart_config[port->type].flags;
+	up->mcr = 0;
+
+	if (port->iotype != up->cur_iotype)
+		set_io_from_upio(port);
+
+	serial8250_rpm_get(up);
+	if (port->type == PORT_16C950) {
+		/* Wake up and initialize UART */
+		up->acr = 0;
+		serial_port_out(port, UART_LCR, UART_LCR_CONF_MODE_B);
+		serial_port_out(port, UART_EFR, UART_EFR_ECB);
+		serial_port_out(port, UART_IER, 0);
+		serial_port_out(port, UART_LCR, 0);
+		serial_icr_write(up, UART_CSR, 0); /* Reset the UART */
+		serial_port_out(port, UART_LCR, UART_LCR_CONF_MODE_B);
+		serial_port_out(port, UART_EFR, UART_EFR_ECB);
+		serial_port_out(port, UART_LCR, 0);
+	}
+
+#ifdef CONFIG_SERIAL_8250_RSA
+	/*
+	 * If this is an RSA port, see if we can kick it up to the
+	 * higher speed clock.
+	 */
+	enable_rsa(up);
+#endif
+
+	if (port->type == PORT_XR17V35X) {
+		/*
+		 * First enable access to IER [7:5], ISR [5:4], FCR [5:4],
+		 * MCR [7:5] and MSR [7:0]
+		 */
+		serial_port_out(port, UART_XR_EFR, UART_EFR_ECB);
+
+		/*
+		 * Make sure all interrups are masked until initialization is
+		 * complete and the FIFOs are cleared
+		 */
+		serial_port_out(port, UART_IER, 0);
+	}
+
+	/*
+	 * Clear the FIFO buffers and disable them.
+	 * (they will be reenabled in set_termios())
+	 */
+	serial8250_clear_fifos(up);
+
+	/*
+	 * Clear the interrupt registers.
+	 */
+	serial_port_in(port, UART_LSR);
+	serial_port_in(port, UART_RX);
+	serial_port_in(port, UART_IIR);
+	serial_port_in(port, UART_MSR);
+
+	/*
+	 * At this point, there's no way the LSR could still be 0xff;
+	 * if it is, then bail out, because there's likely no UART
+	 * here.
+	 */
+	if (!(port->flags & UPF_BUGGY_UART) &&
+	    (serial_port_in(port, UART_LSR) == 0xff)) {
+		printk_ratelimited(KERN_INFO "ttyS%d: LSR safety check engaged!\n",
+				   serial_index(port));
+		retval = -ENODEV;
+		goto out;
+	}
+
+	/*
+	 * For a XR16C850, we need to set the trigger levels
+	 */
+	if (port->type == PORT_16850) {
+		unsigned char fctr;
+
+		serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
+
+		fctr = serial_in(up, UART_FCTR) & ~(UART_FCTR_RX|UART_FCTR_TX);
+		serial_port_out(port, UART_FCTR,
+				fctr | UART_FCTR_TRGD | UART_FCTR_RX);
+		serial_port_out(port, UART_TRG, UART_TRG_96);
+		serial_port_out(port, UART_FCTR,
+				fctr | UART_FCTR_TRGD | UART_FCTR_TX);
+		serial_port_out(port, UART_TRG, UART_TRG_96);
+
+		serial_port_out(port, UART_LCR, 0);
+	}
+
+	if (port->irq) {
+		unsigned char iir1;
+		/*
+		 * Test for UARTs that do not reassert THRE when the
+		 * transmitter is idle and the interrupt has already
+		 * been cleared.  Real 16550s should always reassert
+		 * this interrupt whenever the transmitter is idle and
+		 * the interrupt is enabled.  Delays are necessary to
+		 * allow register changes to become visible.
+		 */
+		spin_lock_irqsave(&port->lock, flags);
+		if (up->port.irqflags & IRQF_SHARED)
+			disable_irq_nosync(port->irq);
+
+		wait_for_xmitr(up, UART_LSR_THRE);
+		serial_port_out_sync(port, UART_IER, UART_IER_THRI);
+		udelay(1); /* allow THRE to set */
+		iir1 = serial_port_in(port, UART_IIR);
+		serial_port_out(port, UART_IER, 0);
+		serial_port_out_sync(port, UART_IER, UART_IER_THRI);
+		udelay(1); /* allow a working UART time to re-assert THRE */
+		iir = serial_port_in(port, UART_IIR);
+		serial_port_out(port, UART_IER, 0);
+
+		if (port->irqflags & IRQF_SHARED)
+			enable_irq(port->irq);
+		spin_unlock_irqrestore(&port->lock, flags);
+
+		/*
+		 * If the interrupt is not reasserted, or we otherwise
+		 * don't trust the iir, setup a timer to kick the UART
+		 * on a regular basis.
+		 */
+		if ((!(iir1 & UART_IIR_NO_INT) && (iir & UART_IIR_NO_INT)) ||
+		    up->port.flags & UPF_BUG_THRE) {
+			up->bugs |= UART_BUG_THRE;
+		}
+	}
+
+	retval = up->ops->setup_irq(up);
+	if (retval)
+		goto out;
+
+	/*
+	 * Now, initialize the UART
+	 */
+	serial_port_out(port, UART_LCR, UART_LCR_WLEN8);
+
+	spin_lock_irqsave(&port->lock, flags);
+	if (up->port.flags & UPF_FOURPORT) {
+		if (!up->port.irq)
+			up->port.mctrl |= TIOCM_OUT1;
+	} else
+		/*
+		 * Most PC uarts need OUT2 raised to enable interrupts.
+		 */
+		if (port->irq)
+			up->port.mctrl |= TIOCM_OUT2;
+
+	serial8250_set_mctrl(port, port->mctrl);
+
+	/* Serial over Lan (SoL) hack:
+	   Intel 8257x Gigabit ethernet chips have a
+	   16550 emulation, to be used for Serial Over Lan.
+	   Those chips take a longer time than a normal
+	   serial device to signalize that a transmission
+	   data was queued. Due to that, the above test generally
+	   fails. One solution would be to delay the reading of
+	   iir. However, this is not reliable, since the timeout
+	   is variable. So, let's just don't test if we receive
+	   TX irq. This way, we'll never enable UART_BUG_TXEN.
+	 */
+	if (up->port.flags & UPF_NO_TXEN_TEST)
+		goto dont_test_tx_en;
+
+	/*
+	 * Do a quick test to see if we receive an
+	 * interrupt when we enable the TX irq.
+	 */
+	serial_port_out(port, UART_IER, UART_IER_THRI);
+	lsr = serial_port_in(port, UART_LSR);
+	iir = serial_port_in(port, UART_IIR);
+	serial_port_out(port, UART_IER, 0);
+
+	if (lsr & UART_LSR_TEMT && iir & UART_IIR_NO_INT) {
+		if (!(up->bugs & UART_BUG_TXEN)) {
+			up->bugs |= UART_BUG_TXEN;
+			pr_debug("ttyS%d - enabling bad tx status workarounds\n",
+				 serial_index(port));
+		}
+	} else {
+		up->bugs &= ~UART_BUG_TXEN;
+	}
+
+dont_test_tx_en:
+	spin_unlock_irqrestore(&port->lock, flags);
+
+	/*
+	 * Clear the interrupt registers again for luck, and clear the
+	 * saved flags to avoid getting false values from polling
+	 * routines or the previous session.
+	 */
+	serial_port_in(port, UART_LSR);
+	serial_port_in(port, UART_RX);
+	serial_port_in(port, UART_IIR);
+	serial_port_in(port, UART_MSR);
+	up->lsr_saved_flags = 0;
+	up->msr_saved_flags = 0;
+
+	/*
+	 * Request DMA channels for both RX and TX.
+	 */
+	if (up->dma) {
+		retval = serial8250_request_dma(up);
+		if (retval) {
+			pr_warn_ratelimited("ttyS%d - failed to request DMA\n",
+					    serial_index(port));
+			up->dma = NULL;
+		}
+	}
+
+	/*
+	 * Set the IER shadow for rx interrupts but defer actual interrupt
+	 * enable until after the FIFOs are enabled; otherwise, an already-
+	 * active sender can swamp the interrupt handler with "too much work".
+	 */
+	up->ier = UART_IER_RLSI | UART_IER_RDI;
+
+	if (port->flags & UPF_FOURPORT) {
+		unsigned int icp;
+		/*
+		 * Enable interrupts on the AST Fourport board
+		 */
+		icp = (port->iobase & 0xfe0) | 0x01f;
+		outb_p(0x80, icp);
+		inb_p(icp);
+	}
+	retval = 0;
+out:
+	serial8250_rpm_put(up);
+	return retval;
+}
+EXPORT_SYMBOL_GPL(serial8250_do_startup);
+
+static int serial8250_startup(struct uart_port *port)
+{
+	if (port->startup)
+		return port->startup(port);
+	return serial8250_do_startup(port);
+}
+
+void serial8250_do_shutdown(struct uart_port *port)
+{
+	struct uart_8250_port *up = up_to_u8250p(port);
+	unsigned long flags;
+
+	serial8250_rpm_get(up);
+	/*
+	 * Disable interrupts from this port
+	 */
+	up->ier = 0;
+	serial_port_out(port, UART_IER, 0);
+
+	if (up->dma)
+		serial8250_release_dma(up);
+
+	spin_lock_irqsave(&port->lock, flags);
+	if (port->flags & UPF_FOURPORT) {
+		/* reset interrupts on the AST Fourport board */
+		inb((port->iobase & 0xfe0) | 0x1f);
+		port->mctrl |= TIOCM_OUT1;
+	} else
+		port->mctrl &= ~TIOCM_OUT2;
+
+	serial8250_set_mctrl(port, port->mctrl);
+	spin_unlock_irqrestore(&port->lock, flags);
+
+	/*
+	 * Disable break condition and FIFOs
+	 */
+	serial_port_out(port, UART_LCR,
+			serial_port_in(port, UART_LCR) & ~UART_LCR_SBC);
+	serial8250_clear_fifos(up);
+
+#ifdef CONFIG_SERIAL_8250_RSA
+	/*
+	 * Reset the RSA board back to 115kbps compat mode.
+	 */
+	disable_rsa(up);
+#endif
+
+	/*
+	 * Read data port to reset things, and then unlink from
+	 * the IRQ chain.
+	 */
+	serial_port_in(port, UART_RX);
+	serial8250_rpm_put(up);
+
+	up->ops->release_irq(up);
+}
+EXPORT_SYMBOL_GPL(serial8250_do_shutdown);
+
+static void serial8250_shutdown(struct uart_port *port)
+{
+	if (port->shutdown)
+		port->shutdown(port);
+	else
+		serial8250_do_shutdown(port);
+}
+
+/*
+ * XR17V35x UARTs have an extra fractional divisor register (DLD)
+ * Calculate divisor with extra 4-bit fractional portion
+ */
+static unsigned int xr17v35x_get_divisor(struct uart_8250_port *up,
+					 unsigned int baud,
+					 unsigned int *frac)
+{
+	struct uart_port *port = &up->port;
+	unsigned int quot_16;
+
+	quot_16 = DIV_ROUND_CLOSEST(port->uartclk, baud);
+	*frac = quot_16 & 0x0f;
+
+	return quot_16 >> 4;
+}
+
+static unsigned int serial8250_get_divisor(struct uart_8250_port *up,
+					   unsigned int baud,
+					   unsigned int *frac)
+{
+	struct uart_port *port = &up->port;
+	unsigned int quot;
+
+	/*
+	 * Handle magic divisors for baud rates above baud_base on
+	 * SMSC SuperIO chips.
+	 *
+	 */
+	if ((port->flags & UPF_MAGIC_MULTIPLIER) &&
+	    baud == (port->uartclk/4))
+		quot = 0x8001;
+	else if ((port->flags & UPF_MAGIC_MULTIPLIER) &&
+		 baud == (port->uartclk/8))
+		quot = 0x8002;
+	else if (up->port.type == PORT_XR17V35X)
+		quot = xr17v35x_get_divisor(up, baud, frac);
+	else
+		quot = uart_get_divisor(port, baud);
+
+	/*
+	 * Oxford Semi 952 rev B workaround
+	 */
+	if (up->bugs & UART_BUG_QUOT && (quot & 0xff) == 0)
+		quot++;
+
+	return quot;
+}
+
+static unsigned char serial8250_compute_lcr(struct uart_8250_port *up,
+					    tcflag_t c_cflag)
+{
+	unsigned char cval;
+
+	switch (c_cflag & CSIZE) {
+	case CS5:
+		cval = UART_LCR_WLEN5;
+		break;
+	case CS6:
+		cval = UART_LCR_WLEN6;
+		break;
+	case CS7:
+		cval = UART_LCR_WLEN7;
+		break;
+	default:
+	case CS8:
+		cval = UART_LCR_WLEN8;
+		break;
+	}
+
+	if (c_cflag & CSTOPB)
+		cval |= UART_LCR_STOP;
+	if (c_cflag & PARENB) {
+		cval |= UART_LCR_PARITY;
+		if (up->bugs & UART_BUG_PARITY)
+			up->fifo_bug = true;
+	}
+	if (!(c_cflag & PARODD))
+		cval |= UART_LCR_EPAR;
+#ifdef CMSPAR
+	if (c_cflag & CMSPAR)
+		cval |= UART_LCR_SPAR;
+#endif
+
+	return cval;
+}
+
+static void serial8250_set_divisor(struct uart_port *port, unsigned int baud,
+			    unsigned int quot, unsigned int quot_frac)
+{
+	struct uart_8250_port *up = up_to_u8250p(port);
+
+	/* Workaround to enable 115200 baud on OMAP1510 internal ports */
+	if (is_omap1510_8250(up)) {
+		if (baud == 115200) {
+			quot = 1;
+			serial_port_out(port, UART_OMAP_OSC_12M_SEL, 1);
+		} else
+			serial_port_out(port, UART_OMAP_OSC_12M_SEL, 0);
+	}
+
+	/*
+	 * For NatSemi, switch to bank 2 not bank 1, to avoid resetting EXCR2,
+	 * otherwise just set DLAB
+	 */
+	if (up->capabilities & UART_NATSEMI)
+		serial_port_out(port, UART_LCR, 0xe0);
+	else
+		serial_port_out(port, UART_LCR, up->lcr | UART_LCR_DLAB);
+
+	serial_dl_write(up, quot);
+
+	/* XR17V35x UARTs have an extra fractional divisor register (DLD) */
+	if (up->port.type == PORT_XR17V35X)
+		serial_port_out(port, 0x2, quot_frac);
+}
+
+void
+serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios,
+		          struct ktermios *old)
+{
+	struct uart_8250_port *up = up_to_u8250p(port);
+	unsigned char cval;
+	unsigned long flags;
+	unsigned int baud, quot, frac = 0;
+
+	cval = serial8250_compute_lcr(up, termios->c_cflag);
+
+	/*
+	 * Ask the core to calculate the divisor for us.
+	 */
+	baud = uart_get_baud_rate(port, termios, old,
+				  port->uartclk / 16 / 0xffff,
+				  port->uartclk / 16);
+	quot = serial8250_get_divisor(up, baud, &frac);
+
+	/*
+	 * Ok, we're now changing the port state.  Do it with
+	 * interrupts disabled.
+	 */
+	serial8250_rpm_get(up);
+	spin_lock_irqsave(&port->lock, flags);
+
+	up->lcr = cval;					/* Save computed LCR */
+
+	if (up->capabilities & UART_CAP_FIFO && port->fifosize > 1) {
+		/* NOTE: If fifo_bug is not set, a user can set RX_trigger. */
+		if ((baud < 2400 && !up->dma) || up->fifo_bug) {
+			up->fcr &= ~UART_FCR_TRIGGER_MASK;
+			up->fcr |= UART_FCR_TRIGGER_1;
+		}
+	}
+
+	/*
+	 * MCR-based auto flow control.  When AFE is enabled, RTS will be
+	 * deasserted when the receive FIFO contains more characters than
+	 * the trigger, or the MCR RTS bit is cleared.  In the case where
+	 * the remote UART is not using CTS auto flow control, we must
+	 * have sufficient FIFO entries for the latency of the remote
+	 * UART to respond.  IOW, at least 32 bytes of FIFO.
+	 */
+	if (up->capabilities & UART_CAP_AFE && port->fifosize >= 32) {
+		up->mcr &= ~UART_MCR_AFE;
+		if (termios->c_cflag & CRTSCTS)
+			up->mcr |= UART_MCR_AFE;
+	}
+
+	/*
+	 * Update the per-port timeout.
+	 */
+	uart_update_timeout(port, termios->c_cflag, baud);
+
+	port->read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
+	if (termios->c_iflag & INPCK)
+		port->read_status_mask |= UART_LSR_FE | UART_LSR_PE;
+	if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
+		port->read_status_mask |= UART_LSR_BI;
+
+	/*
+	 * Characteres to ignore
+	 */
+	port->ignore_status_mask = 0;
+	if (termios->c_iflag & IGNPAR)
+		port->ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
+	if (termios->c_iflag & IGNBRK) {
+		port->ignore_status_mask |= UART_LSR_BI;
+		/*
+		 * If we're ignoring parity and break indicators,
+		 * ignore overruns too (for real raw support).
+		 */
+		if (termios->c_iflag & IGNPAR)
+			port->ignore_status_mask |= UART_LSR_OE;
+	}
+
+	/*
+	 * ignore all characters if CREAD is not set
+	 */
+	if ((termios->c_cflag & CREAD) == 0)
+		port->ignore_status_mask |= UART_LSR_DR;
+
+	/*
+	 * CTS flow control flag and modem status interrupts
+	 */
+	up->ier &= ~UART_IER_MSI;
+	if (!(up->bugs & UART_BUG_NOMSR) &&
+			UART_ENABLE_MS(&up->port, termios->c_cflag))
+		up->ier |= UART_IER_MSI;
+	if (up->capabilities & UART_CAP_UUE)
+		up->ier |= UART_IER_UUE;
+	if (up->capabilities & UART_CAP_RTOIE)
+		up->ier |= UART_IER_RTOIE;
+
+	serial_port_out(port, UART_IER, up->ier);
+
+	if (up->capabilities & UART_CAP_EFR) {
+		unsigned char efr = 0;
+		/*
+		 * TI16C752/Startech hardware flow control.  FIXME:
+		 * - TI16C752 requires control thresholds to be set.
+		 * - UART_MCR_RTS is ineffective if auto-RTS mode is enabled.
+		 */
+		if (termios->c_cflag & CRTSCTS)
+			efr |= UART_EFR_CTS;
+
+		serial_port_out(port, UART_LCR, UART_LCR_CONF_MODE_B);
+		if (port->flags & UPF_EXAR_EFR)
+			serial_port_out(port, UART_XR_EFR, efr);
+		else
+			serial_port_out(port, UART_EFR, efr);
+	}
+
+	serial8250_set_divisor(port, baud, quot, frac);
+
+	/*
+	 * LCR DLAB must be set to enable 64-byte FIFO mode. If the FCR
+	 * is written without DLAB set, this mode will be disabled.
+	 */
+	if (port->type == PORT_16750)
+		serial_port_out(port, UART_FCR, up->fcr);
+
+	serial_port_out(port, UART_LCR, up->lcr);	/* reset DLAB */
+	if (port->type != PORT_16750) {
+		/* emulated UARTs (Lucent Venus 167x) need two steps */
+		if (up->fcr & UART_FCR_ENABLE_FIFO)
+			serial_port_out(port, UART_FCR, UART_FCR_ENABLE_FIFO);
+		serial_port_out(port, UART_FCR, up->fcr);	/* set fcr */
+	}
+	serial8250_set_mctrl(port, port->mctrl);
+	spin_unlock_irqrestore(&port->lock, flags);
+	serial8250_rpm_put(up);
+
+	/* Don't rewrite B0 */
+	if (tty_termios_baud_rate(termios))
+		tty_termios_encode_baud_rate(termios, baud, baud);
+}
+EXPORT_SYMBOL(serial8250_do_set_termios);
+
+static void
+serial8250_set_termios(struct uart_port *port, struct ktermios *termios,
+		       struct ktermios *old)
+{
+	if (port->set_termios)
+		port->set_termios(port, termios, old);
+	else
+		serial8250_do_set_termios(port, termios, old);
+}
+
+static void
+serial8250_set_ldisc(struct uart_port *port, struct ktermios *termios)
+{
+	if (termios->c_line == N_PPS) {
+		port->flags |= UPF_HARDPPS_CD;
+		spin_lock_irq(&port->lock);
+		serial8250_enable_ms(port);
+		spin_unlock_irq(&port->lock);
+	} else {
+		port->flags &= ~UPF_HARDPPS_CD;
+		if (!UART_ENABLE_MS(port, termios->c_cflag)) {
+			spin_lock_irq(&port->lock);
+			serial8250_disable_ms(port);
+			spin_unlock_irq(&port->lock);
+		}
+	}
+}
+
+
+void serial8250_do_pm(struct uart_port *port, unsigned int state,
+		      unsigned int oldstate)
+{
+	struct uart_8250_port *p = up_to_u8250p(port);
+
+	serial8250_set_sleep(p, state != 0);
+}
+EXPORT_SYMBOL(serial8250_do_pm);
+
+static void
+serial8250_pm(struct uart_port *port, unsigned int state,
+	      unsigned int oldstate)
+{
+	if (port->pm)
+		port->pm(port, state, oldstate);
+	else
+		serial8250_do_pm(port, state, oldstate);
+}
+
+static unsigned int serial8250_port_size(struct uart_8250_port *pt)
+{
+	if (pt->port.mapsize)
+		return pt->port.mapsize;
+	if (pt->port.iotype == UPIO_AU) {
+		if (pt->port.type == PORT_RT2880)
+			return 0x100;
+		return 0x1000;
+	}
+	if (is_omap1_8250(pt))
+		return 0x16 << pt->port.regshift;
+
+	return 8 << pt->port.regshift;
+}
+
+/*
+ * Resource handling.
+ */
+static int serial8250_request_std_resource(struct uart_8250_port *up)
+{
+	unsigned int size = serial8250_port_size(up);
+	struct uart_port *port = &up->port;
+	int ret = 0;
+
+	switch (port->iotype) {
+	case UPIO_AU:
+	case UPIO_TSI:
+	case UPIO_MEM32:
+	case UPIO_MEM32BE:
+	case UPIO_MEM:
+		if (!port->mapbase)
+			break;
+
+		if (!request_mem_region(port->mapbase, size, "serial")) {
+			ret = -EBUSY;
+			break;
+		}
+
+		if (port->flags & UPF_IOREMAP) {
+			port->membase = ioremap_nocache(port->mapbase, size);
+			if (!port->membase) {
+				release_mem_region(port->mapbase, size);
+				ret = -ENOMEM;
+			}
+		}
+		break;
+
+	case UPIO_HUB6:
+	case UPIO_PORT:
+		if (!request_region(port->iobase, size, "serial"))
+			ret = -EBUSY;
+		break;
+	}
+	return ret;
+}
+
+static void serial8250_release_std_resource(struct uart_8250_port *up)
+{
+	unsigned int size = serial8250_port_size(up);
+	struct uart_port *port = &up->port;
+
+	switch (port->iotype) {
+	case UPIO_AU:
+	case UPIO_TSI:
+	case UPIO_MEM32:
+	case UPIO_MEM32BE:
+	case UPIO_MEM:
+		if (!port->mapbase)
+			break;
+
+		if (port->flags & UPF_IOREMAP) {
+			iounmap(port->membase);
+			port->membase = NULL;
+		}
+
+		release_mem_region(port->mapbase, size);
+		break;
+
+	case UPIO_HUB6:
+	case UPIO_PORT:
+		release_region(port->iobase, size);
+		break;
+	}
+}
+
+static void serial8250_release_port(struct uart_port *port)
+{
+	struct uart_8250_port *up = up_to_u8250p(port);
+
+	serial8250_release_std_resource(up);
+}
+
+static int serial8250_request_port(struct uart_port *port)
+{
+	struct uart_8250_port *up = up_to_u8250p(port);
+	int ret;
+
+	if (port->type == PORT_8250_CIR)
+		return -ENODEV;
+
+	ret = serial8250_request_std_resource(up);
+
+	return ret;
+}
+
+static int fcr_get_rxtrig_bytes(struct uart_8250_port *up)
+{
+	const struct serial8250_config *conf_type = &uart_config[up->port.type];
+	unsigned char bytes;
+
+	bytes = conf_type->rxtrig_bytes[UART_FCR_R_TRIG_BITS(up->fcr)];
+
+	return bytes ? bytes : -EOPNOTSUPP;
+}
+
+static int bytes_to_fcr_rxtrig(struct uart_8250_port *up, unsigned char bytes)
+{
+	const struct serial8250_config *conf_type = &uart_config[up->port.type];
+	int i;
+
+	if (!conf_type->rxtrig_bytes[UART_FCR_R_TRIG_BITS(UART_FCR_R_TRIG_00)])
+		return -EOPNOTSUPP;
+
+	for (i = 1; i < UART_FCR_R_TRIG_MAX_STATE; i++) {
+		if (bytes < conf_type->rxtrig_bytes[i])
+			/* Use the nearest lower value */
+			return (--i) << UART_FCR_R_TRIG_SHIFT;
+	}
+
+	return UART_FCR_R_TRIG_11;
+}
+
+static int do_get_rxtrig(struct tty_port *port)
+{
+	struct uart_state *state = container_of(port, struct uart_state, port);
+	struct uart_port *uport = state->uart_port;
+	struct uart_8250_port *up =
+		container_of(uport, struct uart_8250_port, port);
+
+	if (!(up->capabilities & UART_CAP_FIFO) || uport->fifosize <= 1)
+		return -EINVAL;
+
+	return fcr_get_rxtrig_bytes(up);
+}
+
+static int do_serial8250_get_rxtrig(struct tty_port *port)
+{
+	int rxtrig_bytes;
+
+	mutex_lock(&port->mutex);
+	rxtrig_bytes = do_get_rxtrig(port);
+	mutex_unlock(&port->mutex);
+
+	return rxtrig_bytes;
+}
+
+static ssize_t serial8250_get_attr_rx_trig_bytes(struct device *dev,
+	struct device_attribute *attr, char *buf)
+{
+	struct tty_port *port = dev_get_drvdata(dev);
+	int rxtrig_bytes;
+
+	rxtrig_bytes = do_serial8250_get_rxtrig(port);
+	if (rxtrig_bytes < 0)
+		return rxtrig_bytes;
+
+	return snprintf(buf, PAGE_SIZE, "%d\n", rxtrig_bytes);
+}
+
+static int do_set_rxtrig(struct tty_port *port, unsigned char bytes)
+{
+	struct uart_state *state = container_of(port, struct uart_state, port);
+	struct uart_port *uport = state->uart_port;
+	struct uart_8250_port *up =
+		container_of(uport, struct uart_8250_port, port);
+	int rxtrig;
+
+	if (!(up->capabilities & UART_CAP_FIFO) || uport->fifosize <= 1 ||
+	    up->fifo_bug)
+		return -EINVAL;
+
+	rxtrig = bytes_to_fcr_rxtrig(up, bytes);
+	if (rxtrig < 0)
+		return rxtrig;
+
+	serial8250_clear_fifos(up);
+	up->fcr &= ~UART_FCR_TRIGGER_MASK;
+	up->fcr |= (unsigned char)rxtrig;
+	serial_out(up, UART_FCR, up->fcr);
+	return 0;
+}
+
+static int do_serial8250_set_rxtrig(struct tty_port *port, unsigned char bytes)
+{
+	int ret;
+
+	mutex_lock(&port->mutex);
+	ret = do_set_rxtrig(port, bytes);
+	mutex_unlock(&port->mutex);
+
+	return ret;
+}
+
+static ssize_t serial8250_set_attr_rx_trig_bytes(struct device *dev,
+	struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct tty_port *port = dev_get_drvdata(dev);
+	unsigned char bytes;
+	int ret;
+
+	if (!count)
+		return -EINVAL;
+
+	ret = kstrtou8(buf, 10, &bytes);
+	if (ret < 0)
+		return ret;
+
+	ret = do_serial8250_set_rxtrig(port, bytes);
+	if (ret < 0)
+		return ret;
+
+	return count;
+}
+
+static DEVICE_ATTR(rx_trig_bytes, S_IRUSR | S_IWUSR | S_IRGRP,
+		   serial8250_get_attr_rx_trig_bytes,
+		   serial8250_set_attr_rx_trig_bytes);
+
+static struct attribute *serial8250_dev_attrs[] = {
+	&dev_attr_rx_trig_bytes.attr,
+	NULL,
+	};
+
+static struct attribute_group serial8250_dev_attr_group = {
+	.attrs = serial8250_dev_attrs,
+	};
+
+static void register_dev_spec_attr_grp(struct uart_8250_port *up)
+{
+	const struct serial8250_config *conf_type = &uart_config[up->port.type];
+
+	if (conf_type->rxtrig_bytes[0])
+		up->port.attr_group = &serial8250_dev_attr_group;
+}
+
+static void serial8250_config_port(struct uart_port *port, int flags)
+{
+	struct uart_8250_port *up = up_to_u8250p(port);
+	int ret;
+
+	if (port->type == PORT_8250_CIR)
+		return;
+
+	/*
+	 * Find the region that we can probe for.  This in turn
+	 * tells us whether we can probe for the type of port.
+	 */
+	ret = serial8250_request_std_resource(up);
+	if (ret < 0)
+		return;
+
+	if (port->iotype != up->cur_iotype)
+		set_io_from_upio(port);
+
+	if (flags & UART_CONFIG_TYPE)
+		autoconfig(up);
+
+	/* if access method is AU, it is a 16550 with a quirk */
+	if (port->type == PORT_16550A && port->iotype == UPIO_AU)
+		up->bugs |= UART_BUG_NOMSR;
+
+	/* HW bugs may trigger IRQ while IIR == NO_INT */
+	if (port->type == PORT_TEGRA)
+		up->bugs |= UART_BUG_NOMSR;
+
+	if (port->type != PORT_UNKNOWN && flags & UART_CONFIG_IRQ)
+		autoconfig_irq(up);
+
+	if (port->type == PORT_UNKNOWN)
+		serial8250_release_std_resource(up);
+
+	/* Fixme: probably not the best place for this */
+	if ((port->type == PORT_XR17V35X) ||
+	   (port->type == PORT_XR17D15X))
+		port->handle_irq = exar_handle_irq;
+
+	register_dev_spec_attr_grp(up);
+	up->fcr = uart_config[up->port.type].fcr;
+}
+
+static int
+serial8250_verify_port(struct uart_port *port, struct serial_struct *ser)
+{
+	if (ser->irq >= nr_irqs || ser->irq < 0 ||
+	    ser->baud_base < 9600 || ser->type < PORT_UNKNOWN ||
+	    ser->type >= ARRAY_SIZE(uart_config) || ser->type == PORT_CIRRUS ||
+	    ser->type == PORT_STARTECH)
+		return -EINVAL;
+	return 0;
+}
+
+static const char *
+serial8250_type(struct uart_port *port)
+{
+	int type = port->type;
+
+	if (type >= ARRAY_SIZE(uart_config))
+		type = 0;
+	return uart_config[type].name;
+}
+
+static const struct uart_ops serial8250_pops = {
+	.tx_empty	= serial8250_tx_empty,
+	.set_mctrl	= serial8250_set_mctrl,
+	.get_mctrl	= serial8250_get_mctrl,
+	.stop_tx	= serial8250_stop_tx,
+	.start_tx	= serial8250_start_tx,
+	.throttle	= serial8250_throttle,
+	.unthrottle	= serial8250_unthrottle,
+	.stop_rx	= serial8250_stop_rx,
+	.enable_ms	= serial8250_enable_ms,
+	.break_ctl	= serial8250_break_ctl,
+	.startup	= serial8250_startup,
+	.shutdown	= serial8250_shutdown,
+	.set_termios	= serial8250_set_termios,
+	.set_ldisc	= serial8250_set_ldisc,
+	.pm		= serial8250_pm,
+	.type		= serial8250_type,
+	.release_port	= serial8250_release_port,
+	.request_port	= serial8250_request_port,
+	.config_port	= serial8250_config_port,
+	.verify_port	= serial8250_verify_port,
+#ifdef CONFIG_CONSOLE_POLL
+	.poll_get_char = serial8250_get_poll_char,
+	.poll_put_char = serial8250_put_poll_char,
+#endif
+};
+
+void serial8250_init_port(struct uart_8250_port *up)
+{
+	struct uart_port *port = &up->port;
+
+	spin_lock_init(&port->lock);
+	port->ops = &serial8250_pops;
+
+	up->cur_iotype = 0xFF;
+}
+EXPORT_SYMBOL_GPL(serial8250_init_port);
+
+void serial8250_set_defaults(struct uart_8250_port *up)
+{
+	struct uart_port *port = &up->port;
+
+	if (up->port.flags & UPF_FIXED_TYPE) {
+		unsigned int type = up->port.type;
+
+		if (!up->port.fifosize)
+			up->port.fifosize = uart_config[type].fifo_size;
+		if (!up->tx_loadsz)
+			up->tx_loadsz = uart_config[type].tx_loadsz;
+		if (!up->capabilities)
+			up->capabilities = uart_config[type].flags;
+	}
+
+	set_io_from_upio(port);
+
+	/* default dma handlers */
+	if (up->dma) {
+		if (!up->dma->tx_dma)
+			up->dma->tx_dma = serial8250_tx_dma;
+		if (!up->dma->rx_dma)
+			up->dma->rx_dma = serial8250_rx_dma;
+	}
+}
+EXPORT_SYMBOL_GPL(serial8250_set_defaults);
+
+#ifdef CONFIG_SERIAL_8250_CONSOLE
+
+static void serial8250_console_putchar(struct uart_port *port, int ch)
+{
+	struct uart_8250_port *up = up_to_u8250p(port);
+
+	wait_for_xmitr(up, UART_LSR_THRE);
+	serial_port_out(port, UART_TX, ch);
+}
+
+/*
+ *	Print a string to the serial port trying not to disturb
+ *	any possible real use of the port...
+ *
+ *	The console_lock must be held when we get here.
+ */
+void serial8250_console_write(struct uart_8250_port *up, const char *s,
+			      unsigned int count)
+{
+	struct uart_port *port = &up->port;
+	unsigned long flags;
+	unsigned int ier;
+	int locked = 1;
+
+	touch_nmi_watchdog();
+
+	serial8250_rpm_get(up);
+
+	if (port->sysrq)
+		locked = 0;
+	else if (oops_in_progress)
+		locked = spin_trylock_irqsave(&port->lock, flags);
+	else
+		spin_lock_irqsave(&port->lock, flags);
+
+	/*
+	 *	First save the IER then disable the interrupts
+	 */
+	ier = serial_port_in(port, UART_IER);
+
+	if (up->capabilities & UART_CAP_UUE)
+		serial_port_out(port, UART_IER, UART_IER_UUE);
+	else
+		serial_port_out(port, UART_IER, 0);
+
+	/* check scratch reg to see if port powered off during system sleep */
+	if (up->canary && (up->canary != serial_port_in(port, UART_SCR))) {
+		struct ktermios termios;
+		unsigned int baud, quot, frac = 0;
+
+		termios.c_cflag = port->cons->cflag;
+		if (port->state->port.tty && termios.c_cflag == 0)
+			termios.c_cflag = port->state->port.tty->termios.c_cflag;
+
+		baud = uart_get_baud_rate(port, &termios, NULL,
+					  port->uartclk / 16 / 0xffff,
+					  port->uartclk / 16);
+		quot = serial8250_get_divisor(up, baud, &frac);
+
+		serial8250_set_divisor(port, baud, quot, frac);
+		serial_port_out(port, UART_LCR, up->lcr);
+		serial_port_out(port, UART_MCR, UART_MCR_DTR | UART_MCR_RTS);
+
+		up->canary = 0;
+	}
+
+	uart_console_write(port, s, count, serial8250_console_putchar);
+
+	/*
+	 *	Finally, wait for transmitter to become empty
+	 *	and restore the IER
+	 */
+	wait_for_xmitr(up, BOTH_EMPTY);
+	serial_port_out(port, UART_IER, ier);
+
+	/*
+	 *	The receive handling will happen properly because the
+	 *	receive ready bit will still be set; it is not cleared
+	 *	on read.  However, modem control will not, we must
+	 *	call it if we have saved something in the saved flags
+	 *	while processing with interrupts off.
+	 */
+	if (up->msr_saved_flags)
+		serial8250_modem_status(up);
+
+	if (locked)
+		spin_unlock_irqrestore(&port->lock, flags);
+	serial8250_rpm_put(up);
+}
+
+static unsigned int probe_baud(struct uart_port *port)
+{
+	unsigned char lcr, dll, dlm;
+	unsigned int quot;
+
+	lcr = serial_port_in(port, UART_LCR);
+	serial_port_out(port, UART_LCR, lcr | UART_LCR_DLAB);
+	dll = serial_port_in(port, UART_DLL);
+	dlm = serial_port_in(port, UART_DLM);
+	serial_port_out(port, UART_LCR, lcr);
+
+	quot = (dlm << 8) | dll;
+	return (port->uartclk / 16) / quot;
+}
+
+int serial8250_console_setup(struct uart_port *port, char *options, bool probe)
+{
+	int baud = 9600;
+	int bits = 8;
+	int parity = 'n';
+	int flow = 'n';
+
+	if (!port->iobase && !port->membase)
+		return -ENODEV;
+
+	if (options)
+		uart_parse_options(options, &baud, &parity, &bits, &flow);
+	else if (probe)
+		baud = probe_baud(port);
+
+	return uart_set_options(port, port->cons, baud, parity, bits, flow);
+}
+
+#endif /* CONFIG_SERIAL_8250_CONSOLE */

drivers/tty/serial/8250/8250_uniphier.c

@@ -218,6 +218,7 @@ static int uniphier_uart_probe(struct platform_device *pdev)
 	ret = serial8250_register_8250_port(&up);
 	if (ret < 0) {
 		dev_err(dev, "failed to register 8250 port\n");
+		clk_disable_unprepare(priv->clk);
 		return ret;
 	}
 

drivers/tty/serial/8250/Makefile

@@ -2,10 +2,11 @@
 # Makefile for the 8250 serial device drivers.
 #
 
-obj-$(CONFIG_SERIAL_8250)		+= 8250.o
+obj-$(CONFIG_SERIAL_8250)		+= 8250.o 8250_base.o
 8250-y					:= 8250_core.o
 8250-$(CONFIG_SERIAL_8250_PNP)		+= 8250_pnp.o
-8250-$(CONFIG_SERIAL_8250_DMA)		+= 8250_dma.o
+8250_base-y				:= 8250_port.o
+8250_base-$(CONFIG_SERIAL_8250_DMA)	+= 8250_dma.o
 obj-$(CONFIG_SERIAL_8250_GSC)		+= 8250_gsc.o
 obj-$(CONFIG_SERIAL_8250_PCI)		+= 8250_pci.o
 obj-$(CONFIG_SERIAL_8250_HP300)		+= 8250_hp300.o

drivers/tty/serial/Kconfig

@@ -47,12 +47,12 @@ config SERIAL_AMBA_PL010_CONSOLE
 
 config SERIAL_AMBA_PL011
 	tristate "ARM AMBA PL011 serial port support"
-	depends on ARM_AMBA
+	depends on ARM_AMBA || SOC_ZX296702
 	select SERIAL_CORE
 	help
 	  This selects the ARM(R) AMBA(R) PrimeCell PL011 UART.  If you have
 	  an Integrator/PP2, Integrator/CP or Versatile platform, say Y or M
-	  here.
+	  here. Say Y or M if you have SOC_ZX296702.
 
 	  If unsure, say N.
 
@@ -594,7 +594,7 @@ config SERIAL_IMX_CONSOLE
 
 config SERIAL_UARTLITE
 	tristate "Xilinx uartlite serial port support"
-	depends on PPC32 || MICROBLAZE || MFD_TIMBERDALE || ARCH_ZYNQ
+	depends on HAS_IOMEM
 	select SERIAL_CORE
 	help
 	  Say Y here if you want to use the Xilinx uartlite serial controller.
@@ -1067,6 +1067,7 @@ config SERIAL_ETRAXFS
 	bool "ETRAX FS serial port support"
 	depends on ETRAX_ARCH_V32 && OF
 	select SERIAL_CORE
+	select SERIAL_MCTRL_GPIO if GPIOLIB
 
 config SERIAL_ETRAXFS_CONSOLE
 	bool "ETRAX FS serial console support"
@@ -1376,7 +1377,8 @@ config SERIAL_ALTERA_UART_CONSOLE
 
 config SERIAL_IFX6X60
         tristate "SPI protocol driver for Infineon 6x60 modem (EXPERIMENTAL)"
-	depends on GPIOLIB && SPI && HAS_DMA
+	depends on GPIOLIB || COMPILE_TEST
+	depends on SPI && HAS_DMA
 	help
 	  Support for the IFX6x60 modem devices on Intel MID platforms.
 

drivers/tty/serial/amba-pl011.c

@@ -74,8 +74,13 @@
 /* There is by now at least one vendor with differing details, so handle it */
 struct vendor_data {
 	unsigned int		ifls;
+	unsigned int		fr_busy;
+	unsigned int		fr_dsr;
+	unsigned int		fr_cts;
+	unsigned int		fr_ri;
 	unsigned int		lcrh_tx;
 	unsigned int		lcrh_rx;
+	u16			*reg_lut;
 	bool			oversampling;
 	bool			dma_threshold;
 	bool			cts_event_workaround;
@@ -85,6 +90,48 @@ struct vendor_data {
 	unsigned int (*get_fifosize)(struct amba_device *dev);
 };
 
+/* Max address offset of register in use is 0x48 */
+#define REG_NR		(0x48 >> 2)
+#define IDX(x)		(x >> 2)
+enum reg_idx {
+	REG_DR		= IDX(UART01x_DR),
+	REG_RSR		= IDX(UART01x_RSR),
+	REG_ST_DMAWM	= IDX(ST_UART011_DMAWM),
+	REG_FR		= IDX(UART01x_FR),
+	REG_ST_LCRH_RX  = IDX(ST_UART011_LCRH_RX),
+	REG_ILPR	= IDX(UART01x_ILPR),
+	REG_IBRD	= IDX(UART011_IBRD),
+	REG_FBRD	= IDX(UART011_FBRD),
+	REG_LCRH	= IDX(UART011_LCRH),
+	REG_CR		= IDX(UART011_CR),
+	REG_IFLS	= IDX(UART011_IFLS),
+	REG_IMSC	= IDX(UART011_IMSC),
+	REG_RIS		= IDX(UART011_RIS),
+	REG_MIS		= IDX(UART011_MIS),
+	REG_ICR		= IDX(UART011_ICR),
+	REG_DMACR	= IDX(UART011_DMACR),
+};
+
+static u16 arm_reg[] = {
+	[REG_DR]		= UART01x_DR,
+	[REG_RSR]		= UART01x_RSR,
+	[REG_ST_DMAWM]		= ~0,
+	[REG_FR]		= UART01x_FR,
+	[REG_ST_LCRH_RX]	= ~0,
+	[REG_ILPR]		= UART01x_ILPR,
+	[REG_IBRD]		= UART011_IBRD,
+	[REG_FBRD]		= UART011_FBRD,
+	[REG_LCRH]		= UART011_LCRH,
+	[REG_CR]		= UART011_CR,
+	[REG_IFLS]		= UART011_IFLS,
+	[REG_IMSC]		= UART011_IMSC,
+	[REG_RIS]		= UART011_RIS,
+	[REG_MIS]		= UART011_MIS,
+	[REG_ICR]		= UART011_ICR,
+	[REG_DMACR]		= UART011_DMACR,
+};
+
+#ifdef CONFIG_ARM_AMBA
 static unsigned int get_fifosize_arm(struct amba_device *dev)
 {
 	return amba_rev(dev) < 3 ? 16 : 32;
@@ -92,8 +139,13 @@ static unsigned int get_fifosize_arm(struct amba_device *dev)
 
 static struct vendor_data vendor_arm = {
 	.ifls			= UART011_IFLS_RX4_8|UART011_IFLS_TX4_8,
-	.lcrh_tx		= UART011_LCRH,
-	.lcrh_rx		= UART011_LCRH,
+	.fr_busy		= UART01x_FR_BUSY,
+	.fr_dsr			= UART01x_FR_DSR,
+	.fr_cts			= UART01x_FR_CTS,
+	.fr_ri			= UART011_FR_RI,
+	.lcrh_tx		= REG_LCRH,
+	.lcrh_rx		= REG_LCRH,
+	.reg_lut		= arm_reg,
 	.oversampling		= false,
 	.dma_threshold		= false,
 	.cts_event_workaround	= false,
@@ -101,8 +153,14 @@ static struct vendor_data vendor_arm = {
 	.fixed_options		= false,
 	.get_fifosize		= get_fifosize_arm,
 };
+#endif
 
 static struct vendor_data vendor_sbsa = {
+	.fr_busy		= UART01x_FR_BUSY,
+	.fr_dsr			= UART01x_FR_DSR,
+	.fr_cts			= UART01x_FR_CTS,
+	.fr_ri			= UART011_FR_RI,
+	.reg_lut		= arm_reg,
 	.oversampling		= false,
 	.dma_threshold		= false,
 	.cts_event_workaround	= false,
@@ -110,6 +168,26 @@ static struct vendor_data vendor_sbsa = {
 	.fixed_options		= true,
 };
 
+#ifdef CONFIG_ARM_AMBA
+static u16 st_reg[] = {
+	[REG_DR]		= UART01x_DR,
+	[REG_RSR]		= UART01x_RSR,
+	[REG_ST_DMAWM]		= ST_UART011_DMAWM,
+	[REG_FR]		= UART01x_FR,
+	[REG_ST_LCRH_RX]	= ST_UART011_LCRH_RX,
+	[REG_ILPR]		= UART01x_ILPR,
+	[REG_IBRD]		= UART011_IBRD,
+	[REG_FBRD]		= UART011_FBRD,
+	[REG_LCRH]		= UART011_LCRH,
+	[REG_CR]		= UART011_CR,
+	[REG_IFLS]		= UART011_IFLS,
+	[REG_IMSC]		= UART011_IMSC,
+	[REG_RIS]		= UART011_RIS,
+	[REG_MIS]		= UART011_MIS,
+	[REG_ICR]		= UART011_ICR,
+	[REG_DMACR]		= UART011_DMACR,
+};
+
 static unsigned int get_fifosize_st(struct amba_device *dev)
 {
 	return 64;
@@ -117,8 +195,13 @@ static unsigned int get_fifosize_st(struct amba_device *dev)
 
 static struct vendor_data vendor_st = {
 	.ifls			= UART011_IFLS_RX_HALF|UART011_IFLS_TX_HALF,
-	.lcrh_tx		= ST_UART011_LCRH_TX,
-	.lcrh_rx		= ST_UART011_LCRH_RX,
+	.fr_busy		= UART01x_FR_BUSY,
+	.fr_dsr			= UART01x_FR_DSR,
+	.fr_cts			= UART01x_FR_CTS,
+	.fr_ri			= UART011_FR_RI,
+	.lcrh_tx		= REG_LCRH,
+	.lcrh_rx		= REG_ST_LCRH_RX,
+	.reg_lut		= st_reg,
 	.oversampling		= true,
 	.dma_threshold		= true,
 	.cts_event_workaround	= true,
@@ -126,6 +209,43 @@ static struct vendor_data vendor_st = {
 	.fixed_options		= false,
 	.get_fifosize		= get_fifosize_st,
 };
+#endif
+
+#ifdef CONFIG_SOC_ZX296702
+static u16 zte_reg[] = {
+	[REG_DR]		= ZX_UART01x_DR,
+	[REG_RSR]		= UART01x_RSR,
+	[REG_ST_DMAWM]		= ST_UART011_DMAWM,
+	[REG_FR]		= ZX_UART01x_FR,
+	[REG_ST_LCRH_RX]	= ST_UART011_LCRH_RX,
+	[REG_ILPR]		= UART01x_ILPR,
+	[REG_IBRD]		= UART011_IBRD,
+	[REG_FBRD]		= UART011_FBRD,
+	[REG_LCRH]		= ZX_UART011_LCRH_TX,
+	[REG_CR]		= ZX_UART011_CR,
+	[REG_IFLS]		= ZX_UART011_IFLS,
+	[REG_IMSC]		= ZX_UART011_IMSC,
+	[REG_RIS]		= ZX_UART011_RIS,
+	[REG_MIS]		= ZX_UART011_MIS,
+	[REG_ICR]		= ZX_UART011_ICR,
+	[REG_DMACR]		= ZX_UART011_DMACR,
+};
+
+static struct vendor_data vendor_zte = {
+	.ifls			= UART011_IFLS_RX4_8|UART011_IFLS_TX4_8,
+	.fr_busy		= ZX_UART01x_FR_BUSY,
+	.fr_dsr			= ZX_UART01x_FR_DSR,
+	.fr_cts			= ZX_UART01x_FR_CTS,
+	.fr_ri			= ZX_UART011_FR_RI,
+	.lcrh_tx		= REG_LCRH,
+	.lcrh_rx		= REG_ST_LCRH_RX,
+	.reg_lut		= zte_reg,
+	.oversampling		= false,
+	.dma_threshold		= false,
+	.cts_event_workaround	= false,
+	.fixed_options		= false,
+};
+#endif
 
 /* Deals with DMA transactions */
 
@@ -164,10 +284,15 @@ struct uart_amba_port {
 	struct uart_port	port;
 	struct clk		*clk;
 	const struct vendor_data *vendor;
+	u16			*reg_lut;
 	unsigned int		dmacr;		/* dma control reg */
 	unsigned int		im;		/* interrupt mask */
 	unsigned int		old_status;
 	unsigned int		fifosize;	/* vendor-specific */
+	unsigned int		fr_busy;        /* vendor-specific */
+	unsigned int		fr_dsr;		/* vendor-specific */
+	unsigned int		fr_cts;         /* vendor-specific */
+	unsigned int		fr_ri;		/* vendor-specific */
 	unsigned int		lcrh_tx;	/* vendor-specific */
 	unsigned int		lcrh_rx;	/* vendor-specific */
 	unsigned int		old_cr;		/* state during shutdown */
@@ -184,6 +309,29 @@ struct uart_amba_port {
 #endif
 };
 
+static bool is_implemented(struct uart_amba_port *uap, unsigned int reg)
+{
+	return uap->reg_lut[reg] != (u16)~0;
+}
+
+static unsigned int pl011_readw(struct uart_amba_port *uap, int index)
+{
+	WARN_ON(index > REG_NR);
+	return readw_relaxed(uap->port.membase + uap->reg_lut[index]);
+}
+
+static void pl011_writew(struct uart_amba_port *uap, int val, int index)
+{
+	WARN_ON(index > REG_NR);
+	writew_relaxed(val, uap->port.membase + uap->reg_lut[index]);
+}
+
+static void pl011_writeb(struct uart_amba_port *uap, u8 val, int index)
+{
+	WARN_ON(index > REG_NR);
+	writeb_relaxed(val, uap->port.membase + uap->reg_lut[index]);
+}
+
 /*
  * Reads up to 256 characters from the FIFO or until it's empty and
  * inserts them into the TTY layer. Returns the number of characters
@@ -196,12 +344,12 @@ static int pl011_fifo_to_tty(struct uart_amba_port *uap)
 	int fifotaken = 0;
 
 	while (max_count--) {
-		status = readw(uap->port.membase + UART01x_FR);
+		status = pl011_readw(uap, REG_FR);
 		if (status & UART01x_FR_RXFE)
 			break;
 
 		/* Take chars from the FIFO and update status */
-		ch = readw(uap->port.membase + UART01x_DR) |
+		ch = pl011_readw(uap, REG_DR) |
 			UART_DUMMY_DR_RX;
 		flag = TTY_NORMAL;
 		uap->port.icount.rx++;
@@ -284,7 +432,7 @@ static void pl011_dma_probe(struct uart_amba_port *uap)
 	struct amba_pl011_data *plat = dev_get_platdata(uap->port.dev);
 	struct device *dev = uap->port.dev;
 	struct dma_slave_config tx_conf = {
-		.dst_addr = uap->port.mapbase + UART01x_DR,
+		.dst_addr = uap->port.mapbase + uap->reg_lut[REG_DR],
 		.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE,
 		.direction = DMA_MEM_TO_DEV,
 		.dst_maxburst = uap->fifosize >> 1,
@@ -339,7 +487,7 @@ static void pl011_dma_probe(struct uart_amba_port *uap)
 
 	if (chan) {
 		struct dma_slave_config rx_conf = {
-			.src_addr = uap->port.mapbase + UART01x_DR,
+			.src_addr = uap->port.mapbase + uap->reg_lut[REG_DR],
 			.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE,
 			.direction = DMA_DEV_TO_MEM,
 			.src_maxburst = uap->fifosize >> 2,
@@ -438,7 +586,7 @@ static void pl011_dma_tx_callback(void *data)
 
 	dmacr = uap->dmacr;
 	uap->dmacr = dmacr & ~UART011_TXDMAE;
-	writew(uap->dmacr, uap->port.membase + UART011_DMACR);
+	pl011_writew(uap, uap->dmacr, REG_DMACR);
 
 	/*
 	 * If TX DMA was disabled, it means that we've stopped the DMA for
@@ -552,7 +700,7 @@ static int pl011_dma_tx_refill(struct uart_amba_port *uap)
 	dma_dev->device_issue_pending(chan);
 
 	uap->dmacr |= UART011_TXDMAE;
-	writew(uap->dmacr, uap->port.membase + UART011_DMACR);
+	pl011_writew(uap, uap->dmacr, REG_DMACR);
 	uap->dmatx.queued = true;
 
 	/*
@@ -588,9 +736,9 @@ static bool pl011_dma_tx_irq(struct uart_amba_port *uap)
 	 */
 	if (uap->dmatx.queued) {
 		uap->dmacr |= UART011_TXDMAE;
-		writew(uap->dmacr, uap->port.membase + UART011_DMACR);
+		pl011_writew(uap, uap->dmacr, REG_DMACR);
 		uap->im &= ~UART011_TXIM;
-		writew(uap->im, uap->port.membase + UART011_IMSC);
+		pl011_writew(uap, uap->im, REG_IMSC);
 		return true;
 	}
 
@@ -600,7 +748,7 @@ static bool pl011_dma_tx_irq(struct uart_amba_port *uap)
 	 */
 	if (pl011_dma_tx_refill(uap) > 0) {
 		uap->im &= ~UART011_TXIM;
-		writew(uap->im, uap->port.membase + UART011_IMSC);
+		pl011_writew(uap, uap->im, REG_IMSC);
 		return true;
 	}
 	return false;
@@ -614,7 +762,7 @@ static inline void pl011_dma_tx_stop(struct uart_amba_port *uap)
 {
 	if (uap->dmatx.queued) {
 		uap->dmacr &= ~UART011_TXDMAE;
-		writew(uap->dmacr, uap->port.membase + UART011_DMACR);
+		pl011_writew(uap, uap->dmacr, REG_DMACR);
 	}
 }
 
@@ -640,14 +788,12 @@ static inline bool pl011_dma_tx_start(struct uart_amba_port *uap)
 		if (!uap->dmatx.queued) {
 			if (pl011_dma_tx_refill(uap) > 0) {
 				uap->im &= ~UART011_TXIM;
-				writew(uap->im, uap->port.membase +
-				       UART011_IMSC);
+				pl011_writew(uap, uap->im, REG_IMSC);
 			} else
 				ret = false;
 		} else if (!(uap->dmacr & UART011_TXDMAE)) {
 			uap->dmacr |= UART011_TXDMAE;
-			writew(uap->dmacr,
-				       uap->port.membase + UART011_DMACR);
+			pl011_writew(uap, uap->dmacr, REG_DMACR);
 		}
 		return ret;
 	}
@@ -658,9 +804,9 @@ static inline bool pl011_dma_tx_start(struct uart_amba_port *uap)
 	 */
 	dmacr = uap->dmacr;
 	uap->dmacr &= ~UART011_TXDMAE;
-	writew(uap->dmacr, uap->port.membase + UART011_DMACR);
+	pl011_writew(uap, uap->dmacr, REG_DMACR);
 
-	if (readw(uap->port.membase + UART01x_FR) & UART01x_FR_TXFF) {
+	if (pl011_readw(uap, REG_FR) & UART01x_FR_TXFF) {
 		/*
 		 * No space in the FIFO, so enable the transmit interrupt
 		 * so we know when there is space.  Note that once we've
@@ -669,13 +815,13 @@ static inline bool pl011_dma_tx_start(struct uart_amba_port *uap)
 		return false;
 	}
 
-	writew(uap->port.x_char, uap->port.membase + UART01x_DR);
+	pl011_writew(uap, uap->port.x_char, REG_DR);
 	uap->port.icount.tx++;
 	uap->port.x_char = 0;
 
 	/* Success - restore the DMA state */
 	uap->dmacr = dmacr;
-	writew(dmacr, uap->port.membase + UART011_DMACR);
+	pl011_writew(uap, dmacr, REG_DMACR);
 
 	return true;
 }
@@ -703,7 +849,7 @@ __acquires(&uap->port.lock)
 			     DMA_TO_DEVICE);
 		uap->dmatx.queued = false;
 		uap->dmacr &= ~UART011_TXDMAE;
-		writew(uap->dmacr, uap->port.membase + UART011_DMACR);
+		pl011_writew(uap, uap->dmacr, REG_DMACR);
 	}
 }
 
@@ -743,11 +889,11 @@ static int pl011_dma_rx_trigger_dma(struct uart_amba_port *uap)
 	dma_async_issue_pending(rxchan);
 
 	uap->dmacr |= UART011_RXDMAE;
-	writew(uap->dmacr, uap->port.membase + UART011_DMACR);
+	pl011_writew(uap, uap->dmacr, REG_DMACR);
 	uap->dmarx.running = true;
 
 	uap->im &= ~UART011_RXIM;
-	writew(uap->im, uap->port.membase + UART011_IMSC);
+	pl011_writew(uap, uap->im, REG_IMSC);
 
 	return 0;
 }
@@ -805,8 +951,9 @@ static void pl011_dma_rx_chars(struct uart_amba_port *uap,
 	 */
 	if (dma_count == pending && readfifo) {
 		/* Clear any error flags */
-		writew(UART011_OEIS | UART011_BEIS | UART011_PEIS | UART011_FEIS,
-		       uap->port.membase + UART011_ICR);
+		pl011_writew(uap,
+			     UART011_OEIS | UART011_BEIS | UART011_PEIS
+			     | UART011_FEIS, REG_ICR);
 
 		/*
 		 * If we read all the DMA'd characters, and we had an
@@ -854,7 +1001,7 @@ static void pl011_dma_rx_irq(struct uart_amba_port *uap)
 
 	/* Disable RX DMA - incoming data will wait in the FIFO */
 	uap->dmacr &= ~UART011_RXDMAE;
-	writew(uap->dmacr, uap->port.membase + UART011_DMACR);
+	pl011_writew(uap, uap->dmacr, REG_DMACR);
 	uap->dmarx.running = false;
 
 	pending = sgbuf->sg.length - state.residue;
@@ -874,7 +1021,7 @@ static void pl011_dma_rx_irq(struct uart_amba_port *uap)
 		dev_dbg(uap->port.dev, "could not retrigger RX DMA job "
 			"fall back to interrupt mode\n");
 		uap->im |= UART011_RXIM;
-		writew(uap->im, uap->port.membase + UART011_IMSC);
+		pl011_writew(uap, uap->im, REG_IMSC);
 	}
 }
 
@@ -922,7 +1069,7 @@ static void pl011_dma_rx_callback(void *data)
 		dev_dbg(uap->port.dev, "could not retrigger RX DMA job "
 			"fall back to interrupt mode\n");
 		uap->im |= UART011_RXIM;
-		writew(uap->im, uap->port.membase + UART011_IMSC);
+		pl011_writew(uap, uap->im, REG_IMSC);
 	}
 }
 
@@ -935,7 +1082,7 @@ static inline void pl011_dma_rx_stop(struct uart_amba_port *uap)
 {
 	/* FIXME.  Just disable the DMA enable */
 	uap->dmacr &= ~UART011_RXDMAE;
-	writew(uap->dmacr, uap->port.membase + UART011_DMACR);
+	pl011_writew(uap, uap->dmacr, REG_DMACR);
 }
 
 /*
@@ -979,7 +1126,7 @@ static void pl011_dma_rx_poll(unsigned long args)
 		spin_lock_irqsave(&uap->port.lock, flags);
 		pl011_dma_rx_stop(uap);
 		uap->im |= UART011_RXIM;
-		writew(uap->im, uap->port.membase + UART011_IMSC);
+		pl011_writew(uap, uap->im, REG_IMSC);
 		spin_unlock_irqrestore(&uap->port.lock, flags);
 
 		uap->dmarx.running = false;
@@ -1041,7 +1188,7 @@ static void pl011_dma_startup(struct uart_amba_port *uap)
 skip_rx:
 	/* Turn on DMA error (RX/TX will be enabled on demand) */
 	uap->dmacr |= UART011_DMAONERR;
-	writew(uap->dmacr, uap->port.membase + UART011_DMACR);
+	pl011_writew(uap, uap->dmacr, REG_DMACR);
 
 	/*
 	 * ST Micro variants has some specific dma burst threshold
@@ -1049,8 +1196,9 @@ skip_rx:
 	 * be issued above/below 16 bytes.
 	 */
 	if (uap->vendor->dma_threshold)
-		writew(ST_UART011_DMAWM_RX_16 | ST_UART011_DMAWM_TX_16,
-			       uap->port.membase + ST_UART011_DMAWM);
+		pl011_writew(uap,
+			     ST_UART011_DMAWM_RX_16 | ST_UART011_DMAWM_TX_16,
+			     REG_ST_DMAWM);
 
 	if (uap->using_rx_dma) {
 		if (pl011_dma_rx_trigger_dma(uap))
@@ -1075,12 +1223,12 @@ static void pl011_dma_shutdown(struct uart_amba_port *uap)
 		return;
 
 	/* Disable RX and TX DMA */
-	while (readw(uap->port.membase + UART01x_FR) & UART01x_FR_BUSY)
+	while (pl011_readw(uap, REG_FR) & uap->fr_busy)
 		barrier();
 
 	spin_lock_irq(&uap->port.lock);
 	uap->dmacr &= ~(UART011_DMAONERR | UART011_RXDMAE | UART011_TXDMAE);
-	writew(uap->dmacr, uap->port.membase + UART011_DMACR);
+	pl011_writew(uap, uap->dmacr, REG_DMACR);
 	spin_unlock_irq(&uap->port.lock);
 
 	if (uap->using_tx_dma) {
@@ -1181,7 +1329,7 @@ static void pl011_stop_tx(struct uart_port *port)
 	    container_of(port, struct uart_amba_port, port);
 
 	uap->im &= ~UART011_TXIM;
-	writew(uap->im, uap->port.membase + UART011_IMSC);
+	pl011_writew(uap, uap->im, REG_IMSC);
 	pl011_dma_tx_stop(uap);
 }
 
@@ -1191,7 +1339,7 @@ static void pl011_tx_chars(struct uart_amba_port *uap, bool from_irq);
 static void pl011_start_tx_pio(struct uart_amba_port *uap)
 {
 	uap->im |= UART011_TXIM;
-	writew(uap->im, uap->port.membase + UART011_IMSC);
+	pl011_writew(uap, uap->im, REG_IMSC);
 	pl011_tx_chars(uap, false);
 }
 
@@ -1211,7 +1359,7 @@ static void pl011_stop_rx(struct uart_port *port)
 
 	uap->im &= ~(UART011_RXIM|UART011_RTIM|UART011_FEIM|
 		     UART011_PEIM|UART011_BEIM|UART011_OEIM);
-	writew(uap->im, uap->port.membase + UART011_IMSC);
+	pl011_writew(uap, uap->im, REG_IMSC);
 
 	pl011_dma_rx_stop(uap);
 }
@@ -1222,7 +1370,7 @@ static void pl011_enable_ms(struct uart_port *port)
 	    container_of(port, struct uart_amba_port, port);
 
 	uap->im |= UART011_RIMIM|UART011_CTSMIM|UART011_DCDMIM|UART011_DSRMIM;
-	writew(uap->im, uap->port.membase + UART011_IMSC);
+	pl011_writew(uap, uap->im, REG_IMSC);
 }
 
 static void pl011_rx_chars(struct uart_amba_port *uap)
@@ -1242,7 +1390,7 @@ __acquires(&uap->port.lock)
 			dev_dbg(uap->port.dev, "could not trigger RX DMA job "
 				"fall back to interrupt mode again\n");
 			uap->im |= UART011_RXIM;
-			writew(uap->im, uap->port.membase + UART011_IMSC);
+			pl011_writew(uap, uap->im, REG_IMSC);
 		} else {
 #ifdef CONFIG_DMA_ENGINE
 			/* Start Rx DMA poll */
@@ -1263,10 +1411,10 @@ static bool pl011_tx_char(struct uart_amba_port *uap, unsigned char c,
 			  bool from_irq)
 {
 	if (unlikely(!from_irq) &&
-	    readw(uap->port.membase + UART01x_FR) & UART01x_FR_TXFF)
+	    pl011_readw(uap, REG_FR) & UART01x_FR_TXFF)
 		return false; /* unable to transmit character */
 
-	writew(c, uap->port.membase + UART01x_DR);
+	pl011_writew(uap, c, REG_DR);
 	uap->port.icount.tx++;
 
 	return true;
@@ -1313,7 +1461,7 @@ static void pl011_modem_status(struct uart_amba_port *uap)
 {
 	unsigned int status, delta;
 
-	status = readw(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
+	status = pl011_readw(uap, REG_FR) & UART01x_FR_MODEM_ANY;
 
 	delta = status ^ uap->old_status;
 	uap->old_status = status;
@@ -1324,11 +1472,11 @@ static void pl011_modem_status(struct uart_amba_port *uap)
 	if (delta & UART01x_FR_DCD)
 		uart_handle_dcd_change(&uap->port, status & UART01x_FR_DCD);
 
-	if (delta & UART01x_FR_DSR)
+	if (delta & uap->fr_dsr)
 		uap->port.icount.dsr++;
 
-	if (delta & UART01x_FR_CTS)
-		uart_handle_cts_change(&uap->port, status & UART01x_FR_CTS);
+	if (delta & uap->fr_cts)
+		uart_handle_cts_change(&uap->port, status & uap->fr_cts);
 
 	wake_up_interruptible(&uap->port.state->port.delta_msr_wait);
 }
@@ -1341,15 +1489,15 @@ static void check_apply_cts_event_workaround(struct uart_amba_port *uap)
 		return;
 
 	/* workaround to make sure that all bits are unlocked.. */
-	writew(0x00, uap->port.membase + UART011_ICR);
+	pl011_writew(uap, 0x00, REG_ICR);
 
 	/*
 	 * WA: introduce 26ns(1 uart clk) delay before W1C;
 	 * single apb access will incur 2 pclk(133.12Mhz) delay,
 	 * so add 2 dummy reads
 	 */
-	dummy_read = readw(uap->port.membase + UART011_ICR);
-	dummy_read = readw(uap->port.membase + UART011_ICR);
+	dummy_read = pl011_readw(uap, REG_ICR);
+	dummy_read = pl011_readw(uap, REG_ICR);
 }
 
 static irqreturn_t pl011_int(int irq, void *dev_id)
@@ -1361,15 +1509,13 @@ static irqreturn_t pl011_int(int irq, void *dev_id)
 	int handled = 0;
 
 	spin_lock_irqsave(&uap->port.lock, flags);
-	imsc = readw(uap->port.membase + UART011_IMSC);
-	status = readw(uap->port.membase + UART011_RIS) & imsc;
+	imsc = pl011_readw(uap, REG_IMSC);
+	status = pl011_readw(uap, REG_RIS) & imsc;
 	if (status) {
 		do {
 			check_apply_cts_event_workaround(uap);
-
-			writew(status & ~(UART011_TXIS|UART011_RTIS|
-					  UART011_RXIS),
-			       uap->port.membase + UART011_ICR);
+			pl011_writew(uap, status & ~(UART011_TXIS|UART011_RTIS|
+				     UART011_RXIS), REG_ICR);
 
 			if (status & (UART011_RTIS|UART011_RXIS)) {
 				if (pl011_dma_rx_running(uap))
@@ -1386,7 +1532,7 @@ static irqreturn_t pl011_int(int irq, void *dev_id)
 			if (pass_counter-- == 0)
 				break;
 
-			status = readw(uap->port.membase + UART011_RIS) & imsc;
+			status = pl011_readw(uap, REG_RIS) & imsc;
 		} while (status != 0);
 		handled = 1;
 	}
@@ -1400,8 +1546,8 @@ static unsigned int pl011_tx_empty(struct uart_port *port)
 {
 	struct uart_amba_port *uap =
 	    container_of(port, struct uart_amba_port, port);
-	unsigned int status = readw(uap->port.membase + UART01x_FR);
-	return status & (UART01x_FR_BUSY|UART01x_FR_TXFF) ? 0 : TIOCSER_TEMT;
+	unsigned int status = pl011_readw(uap, REG_FR);
+	return status & (uap->fr_busy|UART01x_FR_TXFF) ? 0 : TIOCSER_TEMT;
 }
 
 static unsigned int pl011_get_mctrl(struct uart_port *port)
@@ -1409,16 +1555,16 @@ static unsigned int pl011_get_mctrl(struct uart_port *port)
 	struct uart_amba_port *uap =
 	    container_of(port, struct uart_amba_port, port);
 	unsigned int result = 0;
-	unsigned int status = readw(uap->port.membase + UART01x_FR);
+	unsigned int status = pl011_readw(uap, REG_FR);
 
 #define TIOCMBIT(uartbit, tiocmbit)	\
 	if (status & uartbit)		\
 		result |= tiocmbit
 
 	TIOCMBIT(UART01x_FR_DCD, TIOCM_CAR);
-	TIOCMBIT(UART01x_FR_DSR, TIOCM_DSR);
-	TIOCMBIT(UART01x_FR_CTS, TIOCM_CTS);
-	TIOCMBIT(UART011_FR_RI, TIOCM_RNG);
+	TIOCMBIT(uap->fr_dsr, TIOCM_DSR);
+	TIOCMBIT(uap->fr_cts, TIOCM_CTS);
+	TIOCMBIT(uap->fr_ri, TIOCM_RNG);
 #undef TIOCMBIT
 	return result;
 }
@@ -1429,7 +1575,7 @@ static void pl011_set_mctrl(struct uart_port *port, unsigned int mctrl)
 	    container_of(port, struct uart_amba_port, port);
 	unsigned int cr;
 
-	cr = readw(uap->port.membase + UART011_CR);
+	cr = pl011_readw(uap, REG_CR);
 
 #define	TIOCMBIT(tiocmbit, uartbit)		\
 	if (mctrl & tiocmbit)		\
@@ -1449,7 +1595,7 @@ static void pl011_set_mctrl(struct uart_port *port, unsigned int mctrl)
 	}
 #undef TIOCMBIT
 
-	writew(cr, uap->port.membase + UART011_CR);
+	pl011_writew(uap, cr, REG_CR);
 }
 
 static void pl011_break_ctl(struct uart_port *port, int break_state)
@@ -1460,12 +1606,12 @@ static void pl011_break_ctl(struct uart_port *port, int break_state)
 	unsigned int lcr_h;
 
 	spin_lock_irqsave(&uap->port.lock, flags);
-	lcr_h = readw(uap->port.membase + uap->lcrh_tx);
+	lcr_h = pl011_readw(uap, uap->lcrh_tx);
 	if (break_state == -1)
 		lcr_h |= UART01x_LCRH_BRK;
 	else
 		lcr_h &= ~UART01x_LCRH_BRK;
-	writew(lcr_h, uap->port.membase + uap->lcrh_tx);
+	pl011_writew(uap, lcr_h, uap->lcrh_tx);
 	spin_unlock_irqrestore(&uap->port.lock, flags);
 }
 
@@ -1475,9 +1621,8 @@ static void pl011_quiesce_irqs(struct uart_port *port)
 {
 	struct uart_amba_port *uap =
 	    container_of(port, struct uart_amba_port, port);
-	unsigned char __iomem *regs = uap->port.membase;
 
-	writew(readw(regs + UART011_MIS), regs + UART011_ICR);
+	pl011_writew(uap, pl011_readw(uap, REG_MIS), REG_ICR);
 	/*
 	 * There is no way to clear TXIM as this is "ready to transmit IRQ", so
 	 * we simply mask it. start_tx() will unmask it.
@@ -1491,7 +1636,7 @@ static void pl011_quiesce_irqs(struct uart_port *port)
 	 * (including tx queue), so we're also fine with start_tx()'s caller
 	 * side.
 	 */
-	writew(readw(regs + UART011_IMSC) & ~UART011_TXIM, regs + UART011_IMSC);
+	pl011_writew(uap, pl011_readw(uap, REG_IMSC) & ~UART011_TXIM, REG_IMSC);
 }
 
 static int pl011_get_poll_char(struct uart_port *port)
@@ -1506,11 +1651,11 @@ static int pl011_get_poll_char(struct uart_port *port)
 	 */
 	pl011_quiesce_irqs(port);
 
-	status = readw(uap->port.membase + UART01x_FR);
+	status = pl011_readw(uap, REG_FR);
 	if (status & UART01x_FR_RXFE)
 		return NO_POLL_CHAR;
 
-	return readw(uap->port.membase + UART01x_DR);
+	return pl011_readw(uap, REG_DR);
 }
 
 static void pl011_put_poll_char(struct uart_port *port,
@@ -1519,10 +1664,10 @@ static void pl011_put_poll_char(struct uart_port *port,
 	struct uart_amba_port *uap =
 	    container_of(port, struct uart_amba_port, port);
 
-	while (readw(uap->port.membase + UART01x_FR) & UART01x_FR_TXFF)
+	while (pl011_readw(uap, REG_FR) & UART01x_FR_TXFF)
 		barrier();
 
-	writew(ch, uap->port.membase + UART01x_DR);
+	pl011_writew(uap, ch, REG_DR);
 }
 
 #endif /* CONFIG_CONSOLE_POLL */
@@ -1546,15 +1691,15 @@ static int pl011_hwinit(struct uart_port *port)
 	uap->port.uartclk = clk_get_rate(uap->clk);
 
 	/* Clear pending error and receive interrupts */
-	writew(UART011_OEIS | UART011_BEIS | UART011_PEIS | UART011_FEIS |
-	       UART011_RTIS | UART011_RXIS, uap->port.membase + UART011_ICR);
+	pl011_writew(uap, UART011_OEIS | UART011_BEIS | UART011_PEIS |
+		     UART011_FEIS | UART011_RTIS | UART011_RXIS, REG_ICR);
 
 	/*
 	 * Save interrupts enable mask, and enable RX interrupts in case if
 	 * the interrupt is used for NMI entry.
 	 */
-	uap->im = readw(uap->port.membase + UART011_IMSC);
-	writew(UART011_RTIM | UART011_RXIM, uap->port.membase + UART011_IMSC);
+	uap->im = pl011_readw(uap, REG_IMSC);
+	pl011_writew(uap, UART011_RTIM | UART011_RXIM, REG_IMSC);
 
 	if (dev_get_platdata(uap->port.dev)) {
 		struct amba_pl011_data *plat;
@@ -1568,22 +1713,22 @@ static int pl011_hwinit(struct uart_port *port)
 
 static void pl011_write_lcr_h(struct uart_amba_port *uap, unsigned int lcr_h)
 {
-	writew(lcr_h, uap->port.membase + uap->lcrh_rx);
-	if (uap->lcrh_rx != uap->lcrh_tx) {
+	pl011_writew(uap, lcr_h, uap->lcrh_rx);
+	if (is_implemented(uap, REG_ST_LCRH_RX)) {
 		int i;
 		/*
 		 * Wait 10 PCLKs before writing LCRH_TX register,
 		 * to get this delay write read only register 10 times
 		 */
 		for (i = 0; i < 10; ++i)
-			writew(0xff, uap->port.membase + UART011_MIS);
-		writew(lcr_h, uap->port.membase + uap->lcrh_tx);
+			pl011_writew(uap, 0xff, REG_MIS);
+		pl011_writew(uap, lcr_h, uap->lcrh_tx);
 	}
 }
 
 static int pl011_allocate_irq(struct uart_amba_port *uap)
 {
-	writew(uap->im, uap->port.membase + UART011_IMSC);
+	pl011_writew(uap, uap->im, REG_IMSC);
 
 	return request_irq(uap->port.irq, pl011_int, 0, "uart-pl011", uap);
 }
@@ -1598,12 +1743,11 @@ static void pl011_enable_interrupts(struct uart_amba_port *uap)
 	spin_lock_irq(&uap->port.lock);
 
 	/* Clear out any spuriously appearing RX interrupts */
-	writew(UART011_RTIS | UART011_RXIS,
-	       uap->port.membase + UART011_ICR);
+	pl011_writew(uap, UART011_RTIS | UART011_RXIS, REG_ICR);
 	uap->im = UART011_RTIM;
 	if (!pl011_dma_rx_running(uap))
 		uap->im |= UART011_RXIM;
-	writew(uap->im, uap->port.membase + UART011_IMSC);
+	pl011_writew(uap, uap->im, REG_IMSC);
 	spin_unlock_irq(&uap->port.lock);
 }
 
@@ -1622,21 +1766,21 @@ static int pl011_startup(struct uart_port *port)
 	if (retval)
 		goto clk_dis;
 
-	writew(uap->vendor->ifls, uap->port.membase + UART011_IFLS);
+	pl011_writew(uap, uap->vendor->ifls, REG_IFLS);
 
 	spin_lock_irq(&uap->port.lock);
 
 	/* restore RTS and DTR */
 	cr = uap->old_cr & (UART011_CR_RTS | UART011_CR_DTR);
 	cr |= UART01x_CR_UARTEN | UART011_CR_RXE | UART011_CR_TXE;
-	writew(cr, uap->port.membase + UART011_CR);
+	pl011_writew(uap, cr, REG_CR);
 
 	spin_unlock_irq(&uap->port.lock);
 
 	/*
 	 * initialise the old status of the modem signals
 	 */
-	uap->old_status = readw(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
+	uap->old_status = pl011_readw(uap, REG_FR) & UART01x_FR_MODEM_ANY;
 
 	/* Startup DMA */
 	pl011_dma_startup(uap);
@@ -1675,11 +1819,11 @@ static int sbsa_uart_startup(struct uart_port *port)
 static void pl011_shutdown_channel(struct uart_amba_port *uap,
 					unsigned int lcrh)
 {
-      unsigned long val;
+	unsigned long val;
 
-      val = readw(uap->port.membase + lcrh);
-      val &= ~(UART01x_LCRH_BRK | UART01x_LCRH_FEN);
-      writew(val, uap->port.membase + lcrh);
+	val = pl011_readw(uap, lcrh);
+	val &= ~(UART01x_LCRH_BRK | UART01x_LCRH_FEN);
+	pl011_writew(uap, val, lcrh);
 }
 
 /*
@@ -1693,18 +1837,18 @@ static void pl011_disable_uart(struct uart_amba_port *uap)
 
 	uap->autorts = false;
 	spin_lock_irq(&uap->port.lock);
-	cr = readw(uap->port.membase + UART011_CR);
+	cr = pl011_readw(uap, REG_CR);
 	uap->old_cr = cr;
 	cr &= UART011_CR_RTS | UART011_CR_DTR;
 	cr |= UART01x_CR_UARTEN | UART011_CR_TXE;
-	writew(cr, uap->port.membase + UART011_CR);
+	pl011_writew(uap, cr, REG_CR);
 	spin_unlock_irq(&uap->port.lock);
 
 	/*
 	 * disable break condition and fifos
 	 */
 	pl011_shutdown_channel(uap, uap->lcrh_rx);
-	if (uap->lcrh_rx != uap->lcrh_tx)
+	if (is_implemented(uap, REG_ST_LCRH_RX))
 		pl011_shutdown_channel(uap, uap->lcrh_tx);
 }
 
@@ -1714,8 +1858,8 @@ static void pl011_disable_interrupts(struct uart_amba_port *uap)
 
 	/* mask all interrupts and clear all pending ones */
 	uap->im = 0;
-	writew(uap->im, uap->port.membase + UART011_IMSC);
-	writew(0xffff, uap->port.membase + UART011_ICR);
+	pl011_writew(uap, uap->im, REG_IMSC);
+	pl011_writew(uap, 0xffff, REG_ICR);
 
 	spin_unlock_irq(&uap->port.lock);
 }
@@ -1867,8 +2011,8 @@ pl011_set_termios(struct uart_port *port, struct ktermios *termios,
 		pl011_enable_ms(port);
 
 	/* first, disable everything */
-	old_cr = readw(port->membase + UART011_CR);
-	writew(0, port->membase + UART011_CR);
+	old_cr = pl011_readw(uap, REG_CR);
+	pl011_writew(uap, 0, REG_CR);
 
 	if (termios->c_cflag & CRTSCTS) {
 		if (old_cr & UART011_CR_RTS)
@@ -1901,17 +2045,17 @@ pl011_set_termios(struct uart_port *port, struct ktermios *termios,
 			quot -= 2;
 	}
 	/* Set baud rate */
-	writew(quot & 0x3f, port->membase + UART011_FBRD);
-	writew(quot >> 6, port->membase + UART011_IBRD);
+	pl011_writew(uap, quot & 0x3f, REG_FBRD);
+	pl011_writew(uap, quot >> 6, REG_IBRD);
 
 	/*
 	 * ----------v----------v----------v----------v-----
 	 * NOTE: lcrh_tx and lcrh_rx MUST BE WRITTEN AFTER
-	 * UART011_FBRD & UART011_IBRD.
+	 * REG_FBRD & REG_IBRD.
 	 * ----------^----------^----------^----------^-----
 	 */
 	pl011_write_lcr_h(uap, lcr_h);
-	writew(old_cr, port->membase + UART011_CR);
+	pl011_writew(uap, old_cr, REG_CR);
 
 	spin_unlock_irqrestore(&port->lock, flags);
 }
@@ -2052,9 +2196,9 @@ static void pl011_console_putchar(struct uart_port *port, int ch)
 	struct uart_amba_port *uap =
 	    container_of(port, struct uart_amba_port, port);
 
-	while (readw(uap->port.membase + UART01x_FR) & UART01x_FR_TXFF)
+	while (pl011_readw(uap, REG_FR) & UART01x_FR_TXFF)
 		barrier();
-	writew(ch, uap->port.membase + UART01x_DR);
+	pl011_writew(uap, ch, REG_DR);
 }
 
 static void
@@ -2079,10 +2223,10 @@ pl011_console_write(struct console *co, const char *s, unsigned int count)
 	 *	First save the CR then disable the interrupts
 	 */
 	if (!uap->vendor->always_enabled) {
-		old_cr = readw(uap->port.membase + UART011_CR);
+		old_cr = pl011_readw(uap, REG_CR);
 		new_cr = old_cr & ~UART011_CR_CTSEN;
 		new_cr |= UART01x_CR_UARTEN | UART011_CR_TXE;
-		writew(new_cr, uap->port.membase + UART011_CR);
+		pl011_writew(uap, new_cr, REG_CR);
 	}
 
 	uart_console_write(&uap->port, s, count, pl011_console_putchar);
@@ -2092,10 +2236,10 @@ pl011_console_write(struct console *co, const char *s, unsigned int count)
 	 *	and restore the TCR
 	 */
 	do {
-		status = readw(uap->port.membase + UART01x_FR);
-	} while (status & UART01x_FR_BUSY);
+		status = pl011_readw(uap, REG_FR);
+	} while (status & uap->fr_busy);
 	if (!uap->vendor->always_enabled)
-		writew(old_cr, uap->port.membase + UART011_CR);
+		pl011_writew(uap, old_cr, REG_CR);
 
 	if (locked)
 		spin_unlock(&uap->port.lock);
@@ -2108,10 +2252,10 @@ static void __init
 pl011_console_get_options(struct uart_amba_port *uap, int *baud,
 			     int *parity, int *bits)
 {
-	if (readw(uap->port.membase + UART011_CR) & UART01x_CR_UARTEN) {
+	if (pl011_readw(uap, REG_CR) & UART01x_CR_UARTEN) {
 		unsigned int lcr_h, ibrd, fbrd;
 
-		lcr_h = readw(uap->port.membase + uap->lcrh_tx);
+		lcr_h = pl011_readw(uap, uap->lcrh_tx);
 
 		*parity = 'n';
 		if (lcr_h & UART01x_LCRH_PEN) {
@@ -2126,13 +2270,13 @@ pl011_console_get_options(struct uart_amba_port *uap, int *baud,
 		else
 			*bits = 8;
 
-		ibrd = readw(uap->port.membase + UART011_IBRD);
-		fbrd = readw(uap->port.membase + UART011_FBRD);
+		ibrd = pl011_readw(uap, REG_IBRD);
+		fbrd = pl011_readw(uap, REG_FBRD);
 
 		*baud = uap->port.uartclk * 4 / (64 * ibrd + fbrd);
 
 		if (uap->vendor->oversampling) {
-			if (readw(uap->port.membase + UART011_CR)
+			if (pl011_readw(uap, REG_CR)
 				  & ST_UART011_CR_OVSFACT)
 				*baud *= 2;
 		}
@@ -2204,10 +2348,13 @@ static struct console amba_console = {
 
 static void pl011_putc(struct uart_port *port, int c)
 {
-	while (readl(port->membase + UART01x_FR) & UART01x_FR_TXFF)
+	struct uart_amba_port *uap =
+	    container_of(port, struct uart_amba_port, port);
+
+	while (pl011_readw(uap, REG_FR) & UART01x_FR_TXFF)
 		;
-	writeb(c, port->membase + UART01x_DR);
-	while (readl(port->membase + UART01x_FR) & UART01x_FR_BUSY)
+	pl011_writeb(uap, c, REG_DR);
+	while (pl011_readw(uap, REG_FR) & uap->fr_busy)
 		;
 }
 
@@ -2334,8 +2481,8 @@ static int pl011_register_port(struct uart_amba_port *uap)
 	int ret;
 
 	/* Ensure interrupts from this UART are masked and cleared */
-	writew(0, uap->port.membase + UART011_IMSC);
-	writew(0xffff, uap->port.membase + UART011_ICR);
+	pl011_writew(uap, 0, REG_IMSC);
+	pl011_writew(uap, 0xffff, REG_ICR);
 
 	if (!amba_reg.state) {
 		ret = uart_register_driver(&amba_reg);
@@ -2353,6 +2500,7 @@ static int pl011_register_port(struct uart_amba_port *uap)
 	return ret;
 }
 
+#ifdef CONFIG_ARM_AMBA
 static int pl011_probe(struct amba_device *dev, const struct amba_id *id)
 {
 	struct uart_amba_port *uap;
@@ -2373,8 +2521,13 @@ static int pl011_probe(struct amba_device *dev, const struct amba_id *id)
 		return PTR_ERR(uap->clk);
 
 	uap->vendor = vendor;
+	uap->reg_lut = vendor->reg_lut;
 	uap->lcrh_rx = vendor->lcrh_rx;
 	uap->lcrh_tx = vendor->lcrh_tx;
+	uap->fr_busy = vendor->fr_busy;
+	uap->fr_dsr = vendor->fr_dsr;
+	uap->fr_cts = vendor->fr_cts;
+	uap->fr_ri = vendor->fr_ri;
 	uap->fifosize = vendor->get_fifosize(dev);
 	uap->port.irq = dev->irq[0];
 	uap->port.ops = &amba_pl011_pops;
@@ -2398,6 +2551,67 @@ static int pl011_remove(struct amba_device *dev)
 	pl011_unregister_port(uap);
 	return 0;
 }
+#endif
+
+#ifdef CONFIG_SOC_ZX296702
+static int zx_uart_probe(struct platform_device *pdev)
+{
+	struct uart_amba_port *uap;
+	struct vendor_data *vendor = &vendor_zte;
+	struct resource *res;
+	int portnr, ret;
+
+	portnr = pl011_find_free_port();
+	if (portnr < 0)
+		return portnr;
+
+	uap = devm_kzalloc(&pdev->dev, sizeof(struct uart_amba_port),
+			GFP_KERNEL);
+	if (!uap) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	uap->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(uap->clk)) {
+		ret = PTR_ERR(uap->clk);
+		goto out;
+	}
+
+	uap->vendor	= vendor;
+	uap->reg_lut	= vendor->reg_lut;
+	uap->lcrh_rx	= vendor->lcrh_rx;
+	uap->lcrh_tx	= vendor->lcrh_tx;
+	uap->fr_busy	= vendor->fr_busy;
+	uap->fr_dsr	= vendor->fr_dsr;
+	uap->fr_cts	= vendor->fr_cts;
+	uap->fr_ri	= vendor->fr_ri;
+	uap->fifosize	= 16;
+	uap->port.irq	= platform_get_irq(pdev, 0);
+	uap->port.ops	= &amba_pl011_pops;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+
+	ret = pl011_setup_port(&pdev->dev, uap, res, portnr);
+	if (ret)
+		return ret;
+
+	platform_set_drvdata(pdev, uap);
+
+	return pl011_register_port(uap);
+out:
+	return ret;
+}
+
+static int zx_uart_remove(struct platform_device *pdev)
+{
+	struct uart_amba_port *uap = platform_get_drvdata(pdev);
+
+	uart_remove_one_port(&amba_reg, &uap->port);
+	pl011_unregister_port(uap);
+	return 0;
+}
+#endif
 
 #ifdef CONFIG_PM_SLEEP
 static int pl011_suspend(struct device *dev)
@@ -2454,6 +2668,11 @@ static int sbsa_uart_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	uap->vendor	= &vendor_sbsa;
+	uap->reg_lut	= vendor_sbsa.reg_lut;
+	uap->fr_busy	= vendor_sbsa.fr_busy;
+	uap->fr_dsr	= vendor_sbsa.fr_dsr;
+	uap->fr_cts	= vendor_sbsa.fr_cts;
+	uap->fr_ri	= vendor_sbsa.fr_ri;
 	uap->fifosize	= 32;
 	uap->port.irq	= platform_get_irq(pdev, 0);
 	uap->port.ops	= &sbsa_uart_pops;
@@ -2503,6 +2722,7 @@ static struct platform_driver arm_sbsa_uart_platform_driver = {
 	},
 };
 
+#ifdef CONFIG_ARM_AMBA
 static struct amba_id pl011_ids[] = {
 	{
 		.id	= 0x00041011,
@@ -2528,20 +2748,57 @@ static struct amba_driver pl011_driver = {
 	.probe		= pl011_probe,
 	.remove		= pl011_remove,
 };
+#endif
+
+#ifdef CONFIG_SOC_ZX296702
+static const struct of_device_id zx_uart_dt_ids[] = {
+	{ .compatible = "zte,zx296702-uart", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, zx_uart_dt_ids);
+
+static struct platform_driver zx_uart_driver = {
+	.driver = {
+		.name	= "zx-uart",
+		.owner	= THIS_MODULE,
+		.pm	= &pl011_dev_pm_ops,
+		.of_match_table = zx_uart_dt_ids,
+	},
+	.probe		= zx_uart_probe,
+	.remove		= zx_uart_remove,
+};
+#endif
+
 
 static int __init pl011_init(void)
 {
+	int ret;
 	printk(KERN_INFO "Serial: AMBA PL011 UART driver\n");
 
 	if (platform_driver_register(&arm_sbsa_uart_platform_driver))
 		pr_warn("could not register SBSA UART platform driver\n");
-	return amba_driver_register(&pl011_driver);
+
+#ifdef CONFIG_SOC_ZX296702
+	ret = platform_driver_register(&zx_uart_driver);
+	if (ret)
+		pr_warn("could not register ZX UART platform driver\n");
+#endif
+
+#ifdef CONFIG_ARM_AMBA
+	ret = amba_driver_register(&pl011_driver);
+#endif
+	return ret;
 }
 
 static void __exit pl011_exit(void)
 {
 	platform_driver_unregister(&arm_sbsa_uart_platform_driver);
+#ifdef CONFIG_SOC_ZX296702
+	platform_driver_unregister(&zx_uart_driver);
+#endif
+#ifdef CONFIG_ARM_AMBA
 	amba_driver_unregister(&pl011_driver);
+#endif
 }
 
 /*

drivers/tty/serial/atmel_serial.c

@@ -56,6 +56,15 @@
 /* Revisit: We should calculate this based on the actual port settings */
 #define PDC_RX_TIMEOUT		(3 * 10)		/* 3 bytes */
 
+/* The minium number of data FIFOs should be able to contain */
+#define ATMEL_MIN_FIFO_SIZE	8
+/*
+ * These two offsets are substracted from the RX FIFO size to define the RTS
+ * high and low thresholds
+ */
+#define ATMEL_RTS_HIGH_OFFSET	16
+#define ATMEL_RTS_LOW_OFFSET	20
+
 #if defined(CONFIG_SERIAL_ATMEL_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
 #define SUPPORT_SYSRQ
 #endif
@@ -88,37 +97,6 @@ static void atmel_stop_rx(struct uart_port *port);
 
 #define ATMEL_ISR_PASS_LIMIT	256
 
-/* UART registers. CR is write-only, hence no GET macro */
-#define UART_PUT_CR(port,v)	__raw_writel(v, (port)->membase + ATMEL_US_CR)
-#define UART_GET_MR(port)	__raw_readl((port)->membase + ATMEL_US_MR)
-#define UART_PUT_MR(port,v)	__raw_writel(v, (port)->membase + ATMEL_US_MR)
-#define UART_PUT_IER(port,v)	__raw_writel(v, (port)->membase + ATMEL_US_IER)
-#define UART_PUT_IDR(port,v)	__raw_writel(v, (port)->membase + ATMEL_US_IDR)
-#define UART_GET_IMR(port)	__raw_readl((port)->membase + ATMEL_US_IMR)
-#define UART_GET_CSR(port)	__raw_readl((port)->membase + ATMEL_US_CSR)
-#define UART_GET_CHAR(port)	__raw_readl((port)->membase + ATMEL_US_RHR)
-#define UART_PUT_CHAR(port,v)	__raw_writel(v, (port)->membase + ATMEL_US_THR)
-#define UART_GET_BRGR(port)	__raw_readl((port)->membase + ATMEL_US_BRGR)
-#define UART_PUT_BRGR(port,v)	__raw_writel(v, (port)->membase + ATMEL_US_BRGR)
-#define UART_PUT_RTOR(port,v)	__raw_writel(v, (port)->membase + ATMEL_US_RTOR)
-#define UART_PUT_TTGR(port, v)	__raw_writel(v, (port)->membase + ATMEL_US_TTGR)
-#define UART_GET_IP_NAME(port)	__raw_readl((port)->membase + ATMEL_US_NAME)
-#define UART_GET_IP_VERSION(port) __raw_readl((port)->membase + ATMEL_US_VERSION)
-
- /* PDC registers */
-#define UART_PUT_PTCR(port,v)	__raw_writel(v, (port)->membase + ATMEL_PDC_PTCR)
-#define UART_GET_PTSR(port)	__raw_readl((port)->membase + ATMEL_PDC_PTSR)
-
-#define UART_PUT_RPR(port,v)	__raw_writel(v, (port)->membase + ATMEL_PDC_RPR)
-#define UART_GET_RPR(port)	__raw_readl((port)->membase + ATMEL_PDC_RPR)
-#define UART_PUT_RCR(port,v)	__raw_writel(v, (port)->membase + ATMEL_PDC_RCR)
-#define UART_PUT_RNPR(port,v)	__raw_writel(v, (port)->membase + ATMEL_PDC_RNPR)
-#define UART_PUT_RNCR(port,v)	__raw_writel(v, (port)->membase + ATMEL_PDC_RNCR)
-
-#define UART_PUT_TPR(port,v)	__raw_writel(v, (port)->membase + ATMEL_PDC_TPR)
-#define UART_PUT_TCR(port,v)	__raw_writel(v, (port)->membase + ATMEL_PDC_TCR)
-#define UART_GET_TCR(port)	__raw_readl((port)->membase + ATMEL_PDC_TCR)
-
 struct atmel_dma_buffer {
 	unsigned char	*buf;
 	dma_addr_t	dma_addr;
@@ -166,12 +144,16 @@ struct atmel_uart_port {
 	unsigned int		irq_status;
 	unsigned int		irq_status_prev;
 	unsigned int		status_change;
+	unsigned int		tx_len;
 
 	struct circ_buf		rx_ring;
 
 	struct mctrl_gpios	*gpios;
 	int			gpio_irq[UART_GPIO_MAX];
 	unsigned int		tx_done_mask;
+	u32			fifo_size;
+	u32			rts_high;
+	u32			rts_low;
 	bool			ms_irq_enabled;
 	bool			is_usart;	/* usart or uart */
 	struct timer_list	uart_timer;	/* uart timer */
@@ -212,6 +194,43 @@ to_atmel_uart_port(struct uart_port *uart)
 	return container_of(uart, struct atmel_uart_port, uart);
 }
 
+static inline u32 atmel_uart_readl(struct uart_port *port, u32 reg)
+{
+	return __raw_readl(port->membase + reg);
+}
+
+static inline void atmel_uart_writel(struct uart_port *port, u32 reg, u32 value)
+{
+	__raw_writel(value, port->membase + reg);
+}
+
+#ifdef CONFIG_AVR32
+
+/* AVR32 cannot handle 8 or 16bit I/O accesses but only 32bit I/O accesses */
+static inline u8 atmel_uart_read_char(struct uart_port *port)
+{
+	return __raw_readl(port->membase + ATMEL_US_RHR);
+}
+
+static inline void atmel_uart_write_char(struct uart_port *port, u8 value)
+{
+	__raw_writel(value, port->membase + ATMEL_US_THR);
+}
+
+#else
+
+static inline u8 atmel_uart_read_char(struct uart_port *port)
+{
+	return __raw_readb(port->membase + ATMEL_US_RHR);
+}
+
+static inline void atmel_uart_write_char(struct uart_port *port, u8 value)
+{
+	__raw_writeb(value, port->membase + ATMEL_US_THR);
+}
+
+#endif
+
 #ifdef CONFIG_SERIAL_ATMEL_PDC
 static bool atmel_use_pdc_rx(struct uart_port *port)
 {
@@ -257,7 +276,7 @@ static unsigned int atmel_get_lines_status(struct uart_port *port)
 	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
 	unsigned int status, ret = 0;
 
-	status = UART_GET_CSR(port);
+	status = atmel_uart_readl(port, ATMEL_US_CSR);
 
 	mctrl_gpio_get(atmel_port->gpios, &ret);
 
@@ -304,9 +323,9 @@ static int atmel_config_rs485(struct uart_port *port,
 	unsigned int mode;
 
 	/* Disable interrupts */
-	UART_PUT_IDR(port, atmel_port->tx_done_mask);
+	atmel_uart_writel(port, ATMEL_US_IDR, atmel_port->tx_done_mask);
 
-	mode = UART_GET_MR(port);
+	mode = atmel_uart_readl(port, ATMEL_US_MR);
 
 	/* Resetting serial mode to RS232 (0x0) */
 	mode &= ~ATMEL_US_USMODE;
@@ -316,7 +335,8 @@ static int atmel_config_rs485(struct uart_port *port,
 	if (rs485conf->flags & SER_RS485_ENABLED) {
 		dev_dbg(port->dev, "Setting UART to RS485\n");
 		atmel_port->tx_done_mask = ATMEL_US_TXEMPTY;
-		UART_PUT_TTGR(port, rs485conf->delay_rts_after_send);
+		atmel_uart_writel(port, ATMEL_US_TTGR,
+				  rs485conf->delay_rts_after_send);
 		mode |= ATMEL_US_USMODE_RS485;
 	} else {
 		dev_dbg(port->dev, "Setting UART to RS232\n");
@@ -326,10 +346,10 @@ static int atmel_config_rs485(struct uart_port *port,
 		else
 			atmel_port->tx_done_mask = ATMEL_US_TXRDY;
 	}
-	UART_PUT_MR(port, mode);
+	atmel_uart_writel(port, ATMEL_US_MR, mode);
 
 	/* Enable interrupts */
-	UART_PUT_IER(port, atmel_port->tx_done_mask);
+	atmel_uart_writel(port, ATMEL_US_IER, atmel_port->tx_done_mask);
 
 	return 0;
 }
@@ -339,7 +359,9 @@ static int atmel_config_rs485(struct uart_port *port,
  */
 static u_int atmel_tx_empty(struct uart_port *port)
 {
-	return (UART_GET_CSR(port) & ATMEL_US_TXEMPTY) ? TIOCSER_TEMT : 0;
+	return (atmel_uart_readl(port, ATMEL_US_CSR) & ATMEL_US_TXEMPTY) ?
+		TIOCSER_TEMT :
+		0;
 }
 
 /*
@@ -348,13 +370,14 @@ static u_int atmel_tx_empty(struct uart_port *port)
 static void atmel_set_mctrl(struct uart_port *port, u_int mctrl)
 {
 	unsigned int control = 0;
-	unsigned int mode = UART_GET_MR(port);
+	unsigned int mode = atmel_uart_readl(port, ATMEL_US_MR);
 	unsigned int rts_paused, rts_ready;
 	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
 
 	/* override mode to RS485 if needed, otherwise keep the current mode */
 	if (port->rs485.flags & SER_RS485_ENABLED) {
-		UART_PUT_TTGR(port, port->rs485.delay_rts_after_send);
+		atmel_uart_writel(port, ATMEL_US_TTGR,
+				  port->rs485.delay_rts_after_send);
 		mode &= ~ATMEL_US_USMODE;
 		mode |= ATMEL_US_USMODE_RS485;
 	}
@@ -384,7 +407,7 @@ static void atmel_set_mctrl(struct uart_port *port, u_int mctrl)
 	else
 		control |= ATMEL_US_DTRDIS;
 
-	UART_PUT_CR(port, control);
+	atmel_uart_writel(port, ATMEL_US_CR, control);
 
 	mctrl_gpio_set(atmel_port->gpios, mctrl);
 
@@ -395,7 +418,7 @@ static void atmel_set_mctrl(struct uart_port *port, u_int mctrl)
 	else
 		mode |= ATMEL_US_CHMODE_NORMAL;
 
-	UART_PUT_MR(port, mode);
+	atmel_uart_writel(port, ATMEL_US_MR, mode);
 }
 
 /*
@@ -406,7 +429,7 @@ static u_int atmel_get_mctrl(struct uart_port *port)
 	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
 	unsigned int ret = 0, status;
 
-	status = UART_GET_CSR(port);
+	status = atmel_uart_readl(port, ATMEL_US_CSR);
 
 	/*
 	 * The control signals are active low.
@@ -432,10 +455,10 @@ static void atmel_stop_tx(struct uart_port *port)
 
 	if (atmel_use_pdc_tx(port)) {
 		/* disable PDC transmit */
-		UART_PUT_PTCR(port, ATMEL_PDC_TXTDIS);
+		atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_TXTDIS);
 	}
 	/* Disable interrupts */
-	UART_PUT_IDR(port, atmel_port->tx_done_mask);
+	atmel_uart_writel(port, ATMEL_US_IDR, atmel_port->tx_done_mask);
 
 	if ((port->rs485.flags & SER_RS485_ENABLED) &&
 	    !(port->rs485.flags & SER_RS485_RX_DURING_TX))
@@ -450,7 +473,7 @@ static void atmel_start_tx(struct uart_port *port)
 	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
 
 	if (atmel_use_pdc_tx(port)) {
-		if (UART_GET_PTSR(port) & ATMEL_PDC_TXTEN)
+		if (atmel_uart_readl(port, ATMEL_PDC_PTSR) & ATMEL_PDC_TXTEN)
 			/* The transmitter is already running.  Yes, we
 			   really need this.*/
 			return;
@@ -460,10 +483,10 @@ static void atmel_start_tx(struct uart_port *port)
 			atmel_stop_rx(port);
 
 		/* re-enable PDC transmit */
-		UART_PUT_PTCR(port, ATMEL_PDC_TXTEN);
+		atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_TXTEN);
 	}
 	/* Enable interrupts */
-	UART_PUT_IER(port, atmel_port->tx_done_mask);
+	atmel_uart_writel(port, ATMEL_US_IER, atmel_port->tx_done_mask);
 }
 
 /*
@@ -471,17 +494,19 @@ static void atmel_start_tx(struct uart_port *port)
  */
 static void atmel_start_rx(struct uart_port *port)
 {
-	UART_PUT_CR(port, ATMEL_US_RSTSTA);  /* reset status and receiver */
+	/* reset status and receiver */
+	atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_RSTSTA);
 
-	UART_PUT_CR(port, ATMEL_US_RXEN);
+	atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_RXEN);
 
 	if (atmel_use_pdc_rx(port)) {
 		/* enable PDC controller */
-		UART_PUT_IER(port, ATMEL_US_ENDRX | ATMEL_US_TIMEOUT |
-			port->read_status_mask);
-		UART_PUT_PTCR(port, ATMEL_PDC_RXTEN);
+		atmel_uart_writel(port, ATMEL_US_IER,
+				  ATMEL_US_ENDRX | ATMEL_US_TIMEOUT |
+				  port->read_status_mask);
+		atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_RXTEN);
 	} else {
-		UART_PUT_IER(port, ATMEL_US_RXRDY);
+		atmel_uart_writel(port, ATMEL_US_IER, ATMEL_US_RXRDY);
 	}
 }
 
@@ -490,15 +515,16 @@ static void atmel_start_rx(struct uart_port *port)
  */
 static void atmel_stop_rx(struct uart_port *port)
 {
-	UART_PUT_CR(port, ATMEL_US_RXDIS);
+	atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_RXDIS);
 
 	if (atmel_use_pdc_rx(port)) {
 		/* disable PDC receive */
-		UART_PUT_PTCR(port, ATMEL_PDC_RXTDIS);
-		UART_PUT_IDR(port, ATMEL_US_ENDRX | ATMEL_US_TIMEOUT |
-			port->read_status_mask);
+		atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_RXTDIS);
+		atmel_uart_writel(port, ATMEL_US_IDR,
+				  ATMEL_US_ENDRX | ATMEL_US_TIMEOUT |
+				  port->read_status_mask);
 	} else {
-		UART_PUT_IDR(port, ATMEL_US_RXRDY);
+		atmel_uart_writel(port, ATMEL_US_IDR, ATMEL_US_RXRDY);
 	}
 }
 
@@ -538,7 +564,7 @@ static void atmel_enable_ms(struct uart_port *port)
 	else
 		ier |= ATMEL_US_DCDIC;
 
-	UART_PUT_IER(port, ier);
+	atmel_uart_writel(port, ATMEL_US_IER, ier);
 }
 
 /*
@@ -577,7 +603,7 @@ static void atmel_disable_ms(struct uart_port *port)
 	else
 		idr |= ATMEL_US_DCDIC;
 
-	UART_PUT_IDR(port, idr);
+	atmel_uart_writel(port, ATMEL_US_IDR, idr);
 }
 
 /*
@@ -586,9 +612,11 @@ static void atmel_disable_ms(struct uart_port *port)
 static void atmel_break_ctl(struct uart_port *port, int break_state)
 {
 	if (break_state != 0)
-		UART_PUT_CR(port, ATMEL_US_STTBRK);	/* start break */
+		/* start break */
+		atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_STTBRK);
 	else
-		UART_PUT_CR(port, ATMEL_US_STPBRK);	/* stop break */
+		/* stop break */
+		atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_STPBRK);
 }
 
 /*
@@ -622,7 +650,7 @@ atmel_buffer_rx_char(struct uart_port *port, unsigned int status,
 static void atmel_pdc_rxerr(struct uart_port *port, unsigned int status)
 {
 	/* clear error */
-	UART_PUT_CR(port, ATMEL_US_RSTSTA);
+	atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_RSTSTA);
 
 	if (status & ATMEL_US_RXBRK) {
 		/* ignore side-effect */
@@ -645,9 +673,9 @@ static void atmel_rx_chars(struct uart_port *port)
 	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
 	unsigned int status, ch;
 
-	status = UART_GET_CSR(port);
+	status = atmel_uart_readl(port, ATMEL_US_CSR);
 	while (status & ATMEL_US_RXRDY) {
-		ch = UART_GET_CHAR(port);
+		ch = atmel_uart_read_char(port);
 
 		/*
 		 * note that the error handling code is
@@ -658,12 +686,13 @@ static void atmel_rx_chars(struct uart_port *port)
 			     || atmel_port->break_active)) {
 
 			/* clear error */
-			UART_PUT_CR(port, ATMEL_US_RSTSTA);
+			atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_RSTSTA);
 
 			if (status & ATMEL_US_RXBRK
 			    && !atmel_port->break_active) {
 				atmel_port->break_active = 1;
-				UART_PUT_IER(port, ATMEL_US_RXBRK);
+				atmel_uart_writel(port, ATMEL_US_IER,
+						  ATMEL_US_RXBRK);
 			} else {
 				/*
 				 * This is either the end-of-break
@@ -672,14 +701,15 @@ static void atmel_rx_chars(struct uart_port *port)
 				 * being set. In both cases, the next
 				 * RXBRK will indicate start-of-break.
 				 */
-				UART_PUT_IDR(port, ATMEL_US_RXBRK);
+				atmel_uart_writel(port, ATMEL_US_IDR,
+						  ATMEL_US_RXBRK);
 				status &= ~ATMEL_US_RXBRK;
 				atmel_port->break_active = 0;
 			}
 		}
 
 		atmel_buffer_rx_char(port, status, ch);
-		status = UART_GET_CSR(port);
+		status = atmel_uart_readl(port, ATMEL_US_CSR);
 	}
 
 	tasklet_schedule(&atmel_port->tasklet);
@@ -694,16 +724,18 @@ static void atmel_tx_chars(struct uart_port *port)
 	struct circ_buf *xmit = &port->state->xmit;
 	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
 
-	if (port->x_char && UART_GET_CSR(port) & atmel_port->tx_done_mask) {
-		UART_PUT_CHAR(port, port->x_char);
+	if (port->x_char &&
+	    (atmel_uart_readl(port, ATMEL_US_CSR) & atmel_port->tx_done_mask)) {
+		atmel_uart_write_char(port, port->x_char);
 		port->icount.tx++;
 		port->x_char = 0;
 	}
 	if (uart_circ_empty(xmit) || uart_tx_stopped(port))
 		return;
 
-	while (UART_GET_CSR(port) & atmel_port->tx_done_mask) {
-		UART_PUT_CHAR(port, xmit->buf[xmit->tail]);
+	while (atmel_uart_readl(port, ATMEL_US_CSR) &
+	       atmel_port->tx_done_mask) {
+		atmel_uart_write_char(port, xmit->buf[xmit->tail]);
 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 		port->icount.tx++;
 		if (uart_circ_empty(xmit))
@@ -715,7 +747,8 @@ static void atmel_tx_chars(struct uart_port *port)
 
 	if (!uart_circ_empty(xmit))
 		/* Enable interrupts */
-		UART_PUT_IER(port, atmel_port->tx_done_mask);
+		atmel_uart_writel(port, ATMEL_US_IER,
+				  atmel_port->tx_done_mask);
 }
 
 static void atmel_complete_tx_dma(void *arg)
@@ -730,10 +763,10 @@ static void atmel_complete_tx_dma(void *arg)
 
 	if (chan)
 		dmaengine_terminate_all(chan);
-	xmit->tail += sg_dma_len(&atmel_port->sg_tx);
+	xmit->tail += atmel_port->tx_len;
 	xmit->tail &= UART_XMIT_SIZE - 1;
 
-	port->icount.tx += sg_dma_len(&atmel_port->sg_tx);
+	port->icount.tx += atmel_port->tx_len;
 
 	spin_lock_irq(&atmel_port->lock_tx);
 	async_tx_ack(atmel_port->desc_tx);
@@ -781,7 +814,9 @@ static void atmel_tx_dma(struct uart_port *port)
 	struct circ_buf *xmit = &port->state->xmit;
 	struct dma_chan *chan = atmel_port->chan_tx;
 	struct dma_async_tx_descriptor *desc;
-	struct scatterlist *sg = &atmel_port->sg_tx;
+	struct scatterlist sgl[2], *sg, *sg_tx = &atmel_port->sg_tx;
+	unsigned int tx_len, part1_len, part2_len, sg_len;
+	dma_addr_t phys_addr;
 
 	/* Make sure we have an idle channel */
 	if (atmel_port->desc_tx != NULL)
@@ -797,18 +832,46 @@ static void atmel_tx_dma(struct uart_port *port)
 		 * Take the port lock to get a
 		 * consistent xmit buffer state.
 		 */
-		sg->offset = xmit->tail & (UART_XMIT_SIZE - 1);
-		sg_dma_address(sg) = (sg_dma_address(sg) &
-					~(UART_XMIT_SIZE - 1))
-					+ sg->offset;
-		sg_dma_len(sg) = CIRC_CNT_TO_END(xmit->head,
-						xmit->tail,
-						UART_XMIT_SIZE);
-		BUG_ON(!sg_dma_len(sg));
+		tx_len = CIRC_CNT_TO_END(xmit->head,
+					 xmit->tail,
+					 UART_XMIT_SIZE);
+
+		if (atmel_port->fifo_size) {
+			/* multi data mode */
+			part1_len = (tx_len & ~0x3); /* DWORD access */
+			part2_len = (tx_len & 0x3); /* BYTE access */
+		} else {
+			/* single data (legacy) mode */
+			part1_len = 0;
+			part2_len = tx_len; /* BYTE access only */
+		}
+
+		sg_init_table(sgl, 2);
+		sg_len = 0;
+		phys_addr = sg_dma_address(sg_tx) + xmit->tail;
+		if (part1_len) {
+			sg = &sgl[sg_len++];
+			sg_dma_address(sg) = phys_addr;
+			sg_dma_len(sg) = part1_len;
+
+			phys_addr += part1_len;
+		}
+
+		if (part2_len) {
+			sg = &sgl[sg_len++];
+			sg_dma_address(sg) = phys_addr;
+			sg_dma_len(sg) = part2_len;
+		}
+
+		/*
+		 * save tx_len so atmel_complete_tx_dma() will increase
+		 * xmit->tail correctly
+		 */
+		atmel_port->tx_len = tx_len;
 
 		desc = dmaengine_prep_slave_sg(chan,
-					       sg,
-					       1,
+					       sgl,
+					       sg_len,
 					       DMA_MEM_TO_DEV,
 					       DMA_PREP_INTERRUPT |
 					       DMA_CTRL_ACK);
@@ -817,7 +880,7 @@ static void atmel_tx_dma(struct uart_port *port)
 			return;
 		}
 
-		dma_sync_sg_for_device(port->dev, sg, 1, DMA_TO_DEVICE);
+		dma_sync_sg_for_device(port->dev, sg_tx, 1, DMA_TO_DEVICE);
 
 		atmel_port->desc_tx = desc;
 		desc->callback = atmel_complete_tx_dma;
@@ -877,7 +940,9 @@ static int atmel_prepare_tx_dma(struct uart_port *port)
 	/* Configure the slave DMA */
 	memset(&config, 0, sizeof(config));
 	config.direction = DMA_MEM_TO_DEV;
-	config.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+	config.dst_addr_width = (atmel_port->fifo_size) ?
+				DMA_SLAVE_BUSWIDTH_4_BYTES :
+				DMA_SLAVE_BUSWIDTH_1_BYTE;
 	config.dst_addr = port->mapbase + ATMEL_US_THR;
 	config.dst_maxburst = 1;
 
@@ -935,14 +1000,14 @@ static void atmel_rx_from_dma(struct uart_port *port)
 
 
 	/* Reset the UART timeout early so that we don't miss one */
-	UART_PUT_CR(port, ATMEL_US_STTTO);
+	atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_STTTO);
 	dmastat = dmaengine_tx_status(chan,
 				atmel_port->cookie_rx,
 				&state);
 	/* Restart a new tasklet if DMA status is error */
 	if (dmastat == DMA_ERROR) {
 		dev_dbg(port->dev, "Get residue error, restart tasklet\n");
-		UART_PUT_IER(port, ATMEL_US_TIMEOUT);
+		atmel_uart_writel(port, ATMEL_US_IER, ATMEL_US_TIMEOUT);
 		tasklet_schedule(&atmel_port->tasklet);
 		return;
 	}
@@ -1008,7 +1073,7 @@ static void atmel_rx_from_dma(struct uart_port *port)
 	tty_flip_buffer_push(tport);
 	spin_lock(&port->lock);
 
-	UART_PUT_IER(port, ATMEL_US_TIMEOUT);
+	atmel_uart_writel(port, ATMEL_US_IER, ATMEL_US_TIMEOUT);
 }
 
 static int atmel_prepare_rx_dma(struct uart_port *port)
@@ -1118,8 +1183,8 @@ atmel_handle_receive(struct uart_port *port, unsigned int pending)
 		 * the moment.
 		 */
 		if (pending & (ATMEL_US_ENDRX | ATMEL_US_TIMEOUT)) {
-			UART_PUT_IDR(port, (ATMEL_US_ENDRX
-						| ATMEL_US_TIMEOUT));
+			atmel_uart_writel(port, ATMEL_US_IDR,
+					  (ATMEL_US_ENDRX | ATMEL_US_TIMEOUT));
 			tasklet_schedule(&atmel_port->tasklet);
 		}
 
@@ -1130,7 +1195,8 @@ atmel_handle_receive(struct uart_port *port, unsigned int pending)
 
 	if (atmel_use_dma_rx(port)) {
 		if (pending & ATMEL_US_TIMEOUT) {
-			UART_PUT_IDR(port, ATMEL_US_TIMEOUT);
+			atmel_uart_writel(port, ATMEL_US_IDR,
+					  ATMEL_US_TIMEOUT);
 			tasklet_schedule(&atmel_port->tasklet);
 		}
 	}
@@ -1143,8 +1209,8 @@ atmel_handle_receive(struct uart_port *port, unsigned int pending)
 		 * End of break detected. If it came along with a
 		 * character, atmel_rx_chars will handle it.
 		 */
-		UART_PUT_CR(port, ATMEL_US_RSTSTA);
-		UART_PUT_IDR(port, ATMEL_US_RXBRK);
+		atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_RSTSTA);
+		atmel_uart_writel(port, ATMEL_US_IDR, ATMEL_US_RXBRK);
 		atmel_port->break_active = 0;
 	}
 }
@@ -1159,7 +1225,8 @@ atmel_handle_transmit(struct uart_port *port, unsigned int pending)
 
 	if (pending & atmel_port->tx_done_mask) {
 		/* Either PDC or interrupt transmission */
-		UART_PUT_IDR(port, atmel_port->tx_done_mask);
+		atmel_uart_writel(port, ATMEL_US_IDR,
+				  atmel_port->tx_done_mask);
 		tasklet_schedule(&atmel_port->tasklet);
 	}
 }
@@ -1197,7 +1264,7 @@ static irqreturn_t atmel_interrupt(int irq, void *dev_id)
 
 	do {
 		status = atmel_get_lines_status(port);
-		mask = UART_GET_IMR(port);
+		mask = atmel_uart_readl(port, ATMEL_US_IMR);
 		pending = status & mask;
 		if (!gpio_handled) {
 			/*
@@ -1223,7 +1290,7 @@ static irqreturn_t atmel_interrupt(int irq, void *dev_id)
 		if (atmel_port->suspended) {
 			atmel_port->pending |= pending;
 			atmel_port->pending_status = status;
-			UART_PUT_IDR(port, mask);
+			atmel_uart_writel(port, ATMEL_US_IDR, mask);
 			pm_system_wakeup();
 			break;
 		}
@@ -1260,7 +1327,7 @@ static void atmel_tx_pdc(struct uart_port *port)
 	int count;
 
 	/* nothing left to transmit? */
-	if (UART_GET_TCR(port))
+	if (atmel_uart_readl(port, ATMEL_PDC_TCR))
 		return;
 
 	xmit->tail += pdc->ofs;
@@ -1272,7 +1339,7 @@ static void atmel_tx_pdc(struct uart_port *port)
 	/* more to transmit - setup next transfer */
 
 	/* disable PDC transmit */
-	UART_PUT_PTCR(port, ATMEL_PDC_TXTDIS);
+	atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_TXTDIS);
 
 	if (!uart_circ_empty(xmit) && !uart_tx_stopped(port)) {
 		dma_sync_single_for_device(port->dev,
@@ -1283,12 +1350,14 @@ static void atmel_tx_pdc(struct uart_port *port)
 		count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
 		pdc->ofs = count;
 
-		UART_PUT_TPR(port, pdc->dma_addr + xmit->tail);
-		UART_PUT_TCR(port, count);
+		atmel_uart_writel(port, ATMEL_PDC_TPR,
+				  pdc->dma_addr + xmit->tail);
+		atmel_uart_writel(port, ATMEL_PDC_TCR, count);
 		/* re-enable PDC transmit */
-		UART_PUT_PTCR(port, ATMEL_PDC_TXTEN);
+		atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_TXTEN);
 		/* Enable interrupts */
-		UART_PUT_IER(port, atmel_port->tx_done_mask);
+		atmel_uart_writel(port, ATMEL_US_IER,
+				  atmel_port->tx_done_mask);
 	} else {
 		if ((port->rs485.flags & SER_RS485_ENABLED) &&
 		    !(port->rs485.flags & SER_RS485_RX_DURING_TX)) {
@@ -1414,10 +1483,10 @@ static void atmel_rx_from_pdc(struct uart_port *port)
 
 	do {
 		/* Reset the UART timeout early so that we don't miss one */
-		UART_PUT_CR(port, ATMEL_US_STTTO);
+		atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_STTTO);
 
 		pdc = &atmel_port->pdc_rx[rx_idx];
-		head = UART_GET_RPR(port) - pdc->dma_addr;
+		head = atmel_uart_readl(port, ATMEL_PDC_RPR) - pdc->dma_addr;
 		tail = pdc->ofs;
 
 		/* If the PDC has switched buffers, RPR won't contain
@@ -1460,8 +1529,8 @@ static void atmel_rx_from_pdc(struct uart_port *port)
 		 */
 		if (head >= pdc->dma_size) {
 			pdc->ofs = 0;
-			UART_PUT_RNPR(port, pdc->dma_addr);
-			UART_PUT_RNCR(port, pdc->dma_size);
+			atmel_uart_writel(port, ATMEL_PDC_RNPR, pdc->dma_addr);
+			atmel_uart_writel(port, ATMEL_PDC_RNCR, pdc->dma_size);
 
 			rx_idx = !rx_idx;
 			atmel_port->pdc_rx_idx = rx_idx;
@@ -1476,7 +1545,8 @@ static void atmel_rx_from_pdc(struct uart_port *port)
 	tty_flip_buffer_push(tport);
 	spin_lock(&port->lock);
 
-	UART_PUT_IER(port, ATMEL_US_ENDRX | ATMEL_US_TIMEOUT);
+	atmel_uart_writel(port, ATMEL_US_IER,
+			  ATMEL_US_ENDRX | ATMEL_US_TIMEOUT);
 }
 
 static int atmel_prepare_rx_pdc(struct uart_port *port)
@@ -1509,11 +1579,12 @@ static int atmel_prepare_rx_pdc(struct uart_port *port)
 
 	atmel_port->pdc_rx_idx = 0;
 
-	UART_PUT_RPR(port, atmel_port->pdc_rx[0].dma_addr);
-	UART_PUT_RCR(port, PDC_BUFFER_SIZE);
+	atmel_uart_writel(port, ATMEL_PDC_RPR, atmel_port->pdc_rx[0].dma_addr);
+	atmel_uart_writel(port, ATMEL_PDC_RCR, PDC_BUFFER_SIZE);
 
-	UART_PUT_RNPR(port, atmel_port->pdc_rx[1].dma_addr);
-	UART_PUT_RNCR(port, PDC_BUFFER_SIZE);
+	atmel_uart_writel(port, ATMEL_PDC_RNPR,
+			  atmel_port->pdc_rx[1].dma_addr);
+	atmel_uart_writel(port, ATMEL_PDC_RNCR, PDC_BUFFER_SIZE);
 
 	return 0;
 }
@@ -1667,7 +1738,7 @@ static void atmel_set_ops(struct uart_port *port)
 static void atmel_get_ip_name(struct uart_port *port)
 {
 	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
-	int name = UART_GET_IP_NAME(port);
+	int name = atmel_uart_readl(port, ATMEL_US_NAME);
 	u32 version;
 	int usart, uart;
 	/* usart and uart ascii */
@@ -1684,7 +1755,7 @@ static void atmel_get_ip_name(struct uart_port *port)
 		atmel_port->is_usart = false;
 	} else {
 		/* fallback for older SoCs: use version field */
-		version = UART_GET_IP_VERSION(port);
+		version = atmel_uart_readl(port, ATMEL_US_VERSION);
 		switch (version) {
 		case 0x302:
 		case 0x10213:
@@ -1756,7 +1827,7 @@ static int atmel_startup(struct uart_port *port)
 	 * request_irq() is called we could get stuck trying to
 	 * handle an unexpected interrupt
 	 */
-	UART_PUT_IDR(port, -1);
+	atmel_uart_writel(port, ATMEL_US_IDR, -1);
 	atmel_port->ms_irq_enabled = false;
 
 	/*
@@ -1797,6 +1868,32 @@ static int atmel_startup(struct uart_port *port)
 			atmel_set_ops(port);
 	}
 
+	/*
+	 * Enable FIFO when available
+	 */
+	if (atmel_port->fifo_size) {
+		unsigned int txrdym = ATMEL_US_ONE_DATA;
+		unsigned int rxrdym = ATMEL_US_ONE_DATA;
+		unsigned int fmr;
+
+		atmel_uart_writel(port, ATMEL_US_CR,
+				  ATMEL_US_FIFOEN |
+				  ATMEL_US_RXFCLR |
+				  ATMEL_US_TXFLCLR);
+
+		if (atmel_use_dma_tx(port))
+			txrdym = ATMEL_US_FOUR_DATA;
+
+		fmr = ATMEL_US_TXRDYM(txrdym) | ATMEL_US_RXRDYM(rxrdym);
+		if (atmel_port->rts_high &&
+		    atmel_port->rts_low)
+			fmr |=	ATMEL_US_FRTSC |
+				ATMEL_US_RXFTHRES(atmel_port->rts_high) |
+				ATMEL_US_RXFTHRES2(atmel_port->rts_low);
+
+		atmel_uart_writel(port, ATMEL_US_FMR, fmr);
+	}
+
 	/* Save current CSR for comparison in atmel_tasklet_func() */
 	atmel_port->irq_status_prev = atmel_get_lines_status(port);
 	atmel_port->irq_status = atmel_port->irq_status_prev;
@@ -1804,9 +1901,9 @@ static int atmel_startup(struct uart_port *port)
 	/*
 	 * Finally, enable the serial port
 	 */
-	UART_PUT_CR(port, ATMEL_US_RSTSTA | ATMEL_US_RSTRX);
+	atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_RSTSTA | ATMEL_US_RSTRX);
 	/* enable xmit & rcvr */
-	UART_PUT_CR(port, ATMEL_US_TXEN | ATMEL_US_RXEN);
+	atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_TXEN | ATMEL_US_RXEN);
 
 	setup_timer(&atmel_port->uart_timer,
 			atmel_uart_timer_callback,
@@ -1819,13 +1916,14 @@ static int atmel_startup(struct uart_port *port)
 					jiffies + uart_poll_timeout(port));
 		/* set USART timeout */
 		} else {
-			UART_PUT_RTOR(port, PDC_RX_TIMEOUT);
-			UART_PUT_CR(port, ATMEL_US_STTTO);
+			atmel_uart_writel(port, ATMEL_US_RTOR, PDC_RX_TIMEOUT);
+			atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_STTTO);
 
-			UART_PUT_IER(port, ATMEL_US_ENDRX | ATMEL_US_TIMEOUT);
+			atmel_uart_writel(port, ATMEL_US_IER,
+					  ATMEL_US_ENDRX | ATMEL_US_TIMEOUT);
 		}
 		/* enable PDC controller */
-		UART_PUT_PTCR(port, ATMEL_PDC_RXTEN);
+		atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_RXTEN);
 	} else if (atmel_use_dma_rx(port)) {
 		/* set UART timeout */
 		if (!atmel_port->is_usart) {
@@ -1833,14 +1931,15 @@ static int atmel_startup(struct uart_port *port)
 					jiffies + uart_poll_timeout(port));
 		/* set USART timeout */
 		} else {
-			UART_PUT_RTOR(port, PDC_RX_TIMEOUT);
-			UART_PUT_CR(port, ATMEL_US_STTTO);
+			atmel_uart_writel(port, ATMEL_US_RTOR, PDC_RX_TIMEOUT);
+			atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_STTTO);
 
-			UART_PUT_IER(port, ATMEL_US_TIMEOUT);
+			atmel_uart_writel(port, ATMEL_US_IER,
+					  ATMEL_US_TIMEOUT);
 		}
 	} else {
 		/* enable receive only */
-		UART_PUT_IER(port, ATMEL_US_RXRDY);
+		atmel_uart_writel(port, ATMEL_US_IER, ATMEL_US_RXRDY);
 	}
 
 	return 0;
@@ -1860,7 +1959,7 @@ static void atmel_flush_buffer(struct uart_port *port)
 	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
 
 	if (atmel_use_pdc_tx(port)) {
-		UART_PUT_TCR(port, 0);
+		atmel_uart_writel(port, ATMEL_PDC_TCR, 0);
 		atmel_port->pdc_tx.ofs = 0;
 	}
 }
@@ -1892,8 +1991,8 @@ static void atmel_shutdown(struct uart_port *port)
 	atmel_stop_rx(port);
 	atmel_stop_tx(port);
 
-	UART_PUT_CR(port, ATMEL_US_RSTSTA);
-	UART_PUT_IDR(port, -1);
+	atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_RSTSTA);
+	atmel_uart_writel(port, ATMEL_US_IDR, -1);
 
 
 	/*
@@ -1938,12 +2037,12 @@ static void atmel_serial_pm(struct uart_port *port, unsigned int state,
 		clk_prepare_enable(atmel_port->clk);
 
 		/* re-enable interrupts if we disabled some on suspend */
-		UART_PUT_IER(port, atmel_port->backup_imr);
+		atmel_uart_writel(port, ATMEL_US_IER, atmel_port->backup_imr);
 		break;
 	case 3:
 		/* Back up the interrupt mask and disable all interrupts */
-		atmel_port->backup_imr = UART_GET_IMR(port);
-		UART_PUT_IDR(port, -1);
+		atmel_port->backup_imr = atmel_uart_readl(port, ATMEL_US_IMR);
+		atmel_uart_writel(port, ATMEL_US_IDR, -1);
 
 		/*
 		 * Disable the peripheral clock for this serial port.
@@ -1966,7 +2065,7 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios,
 	unsigned int old_mode, mode, imr, quot, baud;
 
 	/* save the current mode register */
-	mode = old_mode = UART_GET_MR(port);
+	mode = old_mode = atmel_uart_readl(port, ATMEL_US_MR);
 
 	/* reset the mode, clock divisor, parity, stop bits and data size */
 	mode &= ~(ATMEL_US_USCLKS | ATMEL_US_CHRL | ATMEL_US_NBSTOP |
@@ -2025,7 +2124,7 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios,
 
 	if (atmel_use_pdc_rx(port))
 		/* need to enable error interrupts */
-		UART_PUT_IER(port, port->read_status_mask);
+		atmel_uart_writel(port, ATMEL_US_IER, port->read_status_mask);
 
 	/*
 	 * Characters to ignore
@@ -2052,15 +2151,16 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios,
 	 * transmitter is empty if requested by the caller, so there's
 	 * no need to wait for it here.
 	 */
-	imr = UART_GET_IMR(port);
-	UART_PUT_IDR(port, -1);
+	imr = atmel_uart_readl(port, ATMEL_US_IMR);
+	atmel_uart_writel(port, ATMEL_US_IDR, -1);
 
 	/* disable receiver and transmitter */
-	UART_PUT_CR(port, ATMEL_US_TXDIS | ATMEL_US_RXDIS);
+	atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_TXDIS | ATMEL_US_RXDIS);
 
 	/* mode */
 	if (port->rs485.flags & SER_RS485_ENABLED) {
-		UART_PUT_TTGR(port, port->rs485.delay_rts_after_send);
+		atmel_uart_writel(port, ATMEL_US_TTGR,
+				  port->rs485.delay_rts_after_send);
 		mode |= ATMEL_US_USMODE_RS485;
 	} else if (termios->c_cflag & CRTSCTS) {
 		/* RS232 with hardware handshake (RTS/CTS) */
@@ -2071,7 +2171,7 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios,
 	}
 
 	/* set the mode, clock divisor, parity, stop bits and data size */
-	UART_PUT_MR(port, mode);
+	atmel_uart_writel(port, ATMEL_US_MR, mode);
 
 	/*
 	 * when switching the mode, set the RTS line state according to the
@@ -2088,16 +2188,16 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios,
 			rts_state = ATMEL_US_RTSEN;
 		}
 
-		UART_PUT_CR(port, rts_state);
+		atmel_uart_writel(port, ATMEL_US_CR, rts_state);
 	}
 
 	/* set the baud rate */
-	UART_PUT_BRGR(port, quot);
-	UART_PUT_CR(port, ATMEL_US_RSTSTA | ATMEL_US_RSTRX);
-	UART_PUT_CR(port, ATMEL_US_TXEN | ATMEL_US_RXEN);
+	atmel_uart_writel(port, ATMEL_US_BRGR, quot);
+	atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_RSTSTA | ATMEL_US_RSTRX);
+	atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_TXEN | ATMEL_US_RXEN);
 
 	/* restore interrupts */
-	UART_PUT_IER(port, imr);
+	atmel_uart_writel(port, ATMEL_US_IER, imr);
 
 	/* CTS flow-control and modem-status interrupts */
 	if (UART_ENABLE_MS(port, termios->c_cflag))
@@ -2208,18 +2308,18 @@ static int atmel_verify_port(struct uart_port *port, struct serial_struct *ser)
 #ifdef CONFIG_CONSOLE_POLL
 static int atmel_poll_get_char(struct uart_port *port)
 {
-	while (!(UART_GET_CSR(port) & ATMEL_US_RXRDY))
+	while (!(atmel_uart_readl(port, ATMEL_US_CSR) & ATMEL_US_RXRDY))
 		cpu_relax();
 
-	return UART_GET_CHAR(port);
+	return atmel_uart_read_char(port);
 }
 
 static void atmel_poll_put_char(struct uart_port *port, unsigned char ch)
 {
-	while (!(UART_GET_CSR(port) & ATMEL_US_TXRDY))
+	while (!(atmel_uart_readl(port, ATMEL_US_CSR) & ATMEL_US_TXRDY))
 		cpu_relax();
 
-	UART_PUT_CHAR(port, ch);
+	atmel_uart_write_char(port, ch);
 }
 #endif
 
@@ -2324,9 +2424,9 @@ struct platform_device *atmel_default_console_device;	/* the serial console devi
 #ifdef CONFIG_SERIAL_ATMEL_CONSOLE
 static void atmel_console_putchar(struct uart_port *port, int ch)
 {
-	while (!(UART_GET_CSR(port) & ATMEL_US_TXRDY))
+	while (!(atmel_uart_readl(port, ATMEL_US_CSR) & ATMEL_US_TXRDY))
 		cpu_relax();
-	UART_PUT_CHAR(port, ch);
+	atmel_uart_write_char(port, ch);
 }
 
 /*
@@ -2342,12 +2442,13 @@ static void atmel_console_write(struct console *co, const char *s, u_int count)
 	/*
 	 * First, save IMR and then disable interrupts
 	 */
-	imr = UART_GET_IMR(port);
-	UART_PUT_IDR(port, ATMEL_US_RXRDY | atmel_port->tx_done_mask);
+	imr = atmel_uart_readl(port, ATMEL_US_IMR);
+	atmel_uart_writel(port, ATMEL_US_IDR,
+			  ATMEL_US_RXRDY | atmel_port->tx_done_mask);
 
 	/* Store PDC transmit status and disable it */
-	pdc_tx = UART_GET_PTSR(port) & ATMEL_PDC_TXTEN;
-	UART_PUT_PTCR(port, ATMEL_PDC_TXTDIS);
+	pdc_tx = atmel_uart_readl(port, ATMEL_PDC_PTSR) & ATMEL_PDC_TXTEN;
+	atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_TXTDIS);
 
 	uart_console_write(port, s, count, atmel_console_putchar);
 
@@ -2356,15 +2457,15 @@ static void atmel_console_write(struct console *co, const char *s, u_int count)
 	 * and restore IMR
 	 */
 	do {
-		status = UART_GET_CSR(port);
+		status = atmel_uart_readl(port, ATMEL_US_CSR);
 	} while (!(status & ATMEL_US_TXRDY));
 
 	/* Restore PDC transmit status */
 	if (pdc_tx)
-		UART_PUT_PTCR(port, ATMEL_PDC_TXTEN);
+		atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_TXTEN);
 
 	/* set interrupts back the way they were */
-	UART_PUT_IER(port, imr);
+	atmel_uart_writel(port, ATMEL_US_IER, imr);
 }
 
 /*
@@ -2380,17 +2481,17 @@ static void __init atmel_console_get_options(struct uart_port *port, int *baud,
 	 * If the baud rate generator isn't running, the port wasn't
 	 * initialized by the boot loader.
 	 */
-	quot = UART_GET_BRGR(port) & ATMEL_US_CD;
+	quot = atmel_uart_readl(port, ATMEL_US_BRGR) & ATMEL_US_CD;
 	if (!quot)
 		return;
 
-	mr = UART_GET_MR(port) & ATMEL_US_CHRL;
+	mr = atmel_uart_readl(port, ATMEL_US_MR) & ATMEL_US_CHRL;
 	if (mr == ATMEL_US_CHRL_8)
 		*bits = 8;
 	else
 		*bits = 7;
 
-	mr = UART_GET_MR(port) & ATMEL_US_PAR;
+	mr = atmel_uart_readl(port, ATMEL_US_MR) & ATMEL_US_PAR;
 	if (mr == ATMEL_US_PAR_EVEN)
 		*parity = 'e';
 	else if (mr == ATMEL_US_PAR_ODD)
@@ -2423,9 +2524,9 @@ static int __init atmel_console_setup(struct console *co, char *options)
 	if (ret)
 		return ret;
 
-	UART_PUT_IDR(port, -1);
-	UART_PUT_CR(port, ATMEL_US_RSTSTA | ATMEL_US_RSTRX);
-	UART_PUT_CR(port, ATMEL_US_TXEN | ATMEL_US_RXEN);
+	atmel_uart_writel(port, ATMEL_US_IDR, -1);
+	atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_RSTSTA | ATMEL_US_RSTRX);
+	atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_TXEN | ATMEL_US_RXEN);
 
 	if (options)
 		uart_parse_options(options, &baud, &parity, &bits, &flow);
@@ -2532,7 +2633,8 @@ static int atmel_serial_suspend(struct platform_device *pdev,
 
 	if (atmel_is_console_port(port) && console_suspend_enabled) {
 		/* Drain the TX shifter */
-		while (!(UART_GET_CSR(port) & ATMEL_US_TXEMPTY))
+		while (!(atmel_uart_readl(port, ATMEL_US_CSR) &
+			 ATMEL_US_TXEMPTY))
 			cpu_relax();
 	}
 
@@ -2599,6 +2701,48 @@ static int atmel_init_gpios(struct atmel_uart_port *p, struct device *dev)
 	return 0;
 }
 
+static void atmel_serial_probe_fifos(struct atmel_uart_port *port,
+				     struct platform_device *pdev)
+{
+	port->fifo_size = 0;
+	port->rts_low = 0;
+	port->rts_high = 0;
+
+	if (of_property_read_u32(pdev->dev.of_node,
+				 "atmel,fifo-size",
+				 &port->fifo_size))
+		return;
+
+	if (!port->fifo_size)
+		return;
+
+	if (port->fifo_size < ATMEL_MIN_FIFO_SIZE) {
+		port->fifo_size = 0;
+		dev_err(&pdev->dev, "Invalid FIFO size\n");
+		return;
+	}
+
+	/*
+	 * 0 <= rts_low <= rts_high <= fifo_size
+	 * Once their CTS line asserted by the remote peer, some x86 UARTs tend
+	 * to flush their internal TX FIFO, commonly up to 16 data, before
+	 * actually stopping to send new data. So we try to set the RTS High
+	 * Threshold to a reasonably high value respecting this 16 data
+	 * empirical rule when possible.
+	 */
+	port->rts_high = max_t(int, port->fifo_size >> 1,
+			       port->fifo_size - ATMEL_RTS_HIGH_OFFSET);
+	port->rts_low  = max_t(int, port->fifo_size >> 2,
+			       port->fifo_size - ATMEL_RTS_LOW_OFFSET);
+
+	dev_info(&pdev->dev, "Using FIFO (%u data)\n",
+		 port->fifo_size);
+	dev_dbg(&pdev->dev, "RTS High Threshold : %2u data\n",
+		port->rts_high);
+	dev_dbg(&pdev->dev, "RTS Low Threshold  : %2u data\n",
+		port->rts_low);
+}
+
 static int atmel_serial_probe(struct platform_device *pdev)
 {
 	struct atmel_uart_port *port;
@@ -2635,6 +2779,7 @@ static int atmel_serial_probe(struct platform_device *pdev)
 	port = &atmel_ports[ret];
 	port->backup_imr = 0;
 	port->uart.line = ret;
+	atmel_serial_probe_fifos(port, pdev);
 
 	spin_lock_init(&port->lock_suspended);
 
@@ -2684,8 +2829,9 @@ static int atmel_serial_probe(struct platform_device *pdev)
 	clk_prepare_enable(port->clk);
 
 	if (rs485_enabled) {
-		UART_PUT_MR(&port->uart, ATMEL_US_USMODE_NORMAL);
-		UART_PUT_CR(&port->uart, ATMEL_US_RTSEN);
+		atmel_uart_writel(&port->uart, ATMEL_US_MR,
+				  ATMEL_US_USMODE_NORMAL);
+		atmel_uart_writel(&port->uart, ATMEL_US_CR, ATMEL_US_RTSEN);
 	}
 
 	/*

drivers/tty/serial/etraxfs-uart.c

@@ -10,6 +10,8 @@
 #include <linux/of_address.h>
 #include <hwregs/ser_defs.h>
 
+#include "serial_mctrl_gpio.h"
+
 #define DRV_NAME "etraxfs-uart"
 #define UART_NR CONFIG_ETRAX_SERIAL_PORTS
 
@@ -28,10 +30,7 @@ struct uart_cris_port {
 
 	void __iomem *regi_ser;
 
-	struct gpio_desc *dtr_pin;
-	struct gpio_desc *dsr_pin;
-	struct gpio_desc *ri_pin;
-	struct gpio_desc *cd_pin;
+	struct mctrl_gpios *gpios;
 
 	int write_ongoing;
 };
@@ -112,17 +111,10 @@ cris_console_setup(struct console *co, char *options)
 	return 0;
 }
 
-static struct tty_driver *cris_console_device(struct console *co, int *index)
-{
-	struct uart_driver *p = co->data;
-	*index = co->index;
-	return p->tty_driver;
-}
-
 static struct console cris_console = {
 	.name = "ttyS",
 	.write = cris_console_write,
-	.device = cris_console_device,
+	.device = uart_console_device,
 	.setup = cris_console_setup,
 	.flags = CON_PRINTBUFFER,
 	.index = -1,
@@ -373,14 +365,6 @@ static void etraxfs_uart_stop_rx(struct uart_port *port)
 	REG_WR(ser, regi_ser, rw_rec_ctrl, rec_ctrl);
 }
 
-static void etraxfs_uart_enable_ms(struct uart_port *port)
-{
-}
-
-static void check_modem_status(struct uart_cris_port *up)
-{
-}
-
 static unsigned int etraxfs_uart_tx_empty(struct uart_port *port)
 {
 	struct uart_cris_port *up = (struct uart_cris_port *)port;
@@ -404,21 +388,9 @@ static unsigned int etraxfs_uart_get_mctrl(struct uart_port *port)
 	ret = 0;
 	if (crisv32_serial_get_rts(up))
 		ret |= TIOCM_RTS;
-	/* DTR is active low */
-	if (up->dtr_pin && !gpiod_get_raw_value(up->dtr_pin))
-		ret |= TIOCM_DTR;
-	/* CD is active low */
-	if (up->cd_pin && !gpiod_get_raw_value(up->cd_pin))
-		ret |= TIOCM_CD;
-	/* RI is active low */
-	if (up->ri_pin && !gpiod_get_raw_value(up->ri_pin))
-		ret |= TIOCM_RI;
-	/* DSR is active low */
-	if (up->dsr_pin && !gpiod_get_raw_value(up->dsr_pin))
-		ret |= TIOCM_DSR;
 	if (crisv32_serial_get_cts(up))
 		ret |= TIOCM_CTS;
-	return ret;
+	return mctrl_gpio_get(up->gpios, &ret);
 }
 
 static void etraxfs_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
@@ -426,15 +398,7 @@ static void etraxfs_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
 	struct uart_cris_port *up = (struct uart_cris_port *)port;
 
 	crisv32_serial_set_rts(up, mctrl & TIOCM_RTS ? 1 : 0, 0);
-	/* DTR is active low */
-	if (up->dtr_pin)
-		gpiod_set_raw_value(up->dtr_pin, mctrl & TIOCM_DTR ? 0 : 1);
-	/* RI is active low */
-	if (up->ri_pin)
-		gpiod_set_raw_value(up->ri_pin, mctrl & TIOCM_RNG ? 0 : 1);
-	/* CD is active low */
-	if (up->cd_pin)
-		gpiod_set_raw_value(up->cd_pin, mctrl & TIOCM_CD ? 0 : 1);
+	mctrl_gpio_set(up->gpios, mctrl);
 }
 
 static void etraxfs_uart_break_ctl(struct uart_port *port, int break_state)
@@ -598,7 +562,6 @@ ser_interrupt(int irq, void *dev_id)
 			receive_chars_no_dma(up);
 			handled = 1;
 		}
-		check_modem_status(up);
 
 		if (masked_intr.tr_rdy) {
 			transmit_chars_no_dma(up);
@@ -862,7 +825,6 @@ static const struct uart_ops etraxfs_uart_pops = {
 	.start_tx = etraxfs_uart_start_tx,
 	.send_xchar = etraxfs_uart_send_xchar,
 	.stop_rx = etraxfs_uart_stop_rx,
-	.enable_ms = etraxfs_uart_enable_ms,
 	.break_ctl = etraxfs_uart_break_ctl,
 	.startup = etraxfs_uart_startup,
 	.shutdown = etraxfs_uart_shutdown,
@@ -930,11 +892,12 @@ static int etraxfs_uart_probe(struct platform_device *pdev)
 
 	up->irq = irq_of_parse_and_map(np, 0);
 	up->regi_ser = of_iomap(np, 0);
-	up->dtr_pin = devm_gpiod_get_optional(&pdev->dev, "dtr");
-	up->dsr_pin = devm_gpiod_get_optional(&pdev->dev, "dsr");
-	up->ri_pin = devm_gpiod_get_optional(&pdev->dev, "ri");
-	up->cd_pin = devm_gpiod_get_optional(&pdev->dev, "cd");
 	up->port.dev = &pdev->dev;
+
+	up->gpios = mctrl_gpio_init(&pdev->dev, 0);
+	if (IS_ERR(up->gpios))
+		return PTR_ERR(up->gpios);
+
 	cris_serial_port_init(&up->port, dev_id);
 
 	etraxfs_uart_ports[dev_id] = up;

drivers/tty/serial/imx.c

@@ -216,6 +216,8 @@ struct imx_port {
 	unsigned int		tx_bytes;
 	unsigned int		dma_tx_nents;
 	wait_queue_head_t	dma_wait;
+	unsigned int            saved_reg[10];
+	bool			context_saved;
 };
 
 struct imx_port_ucrs {
@@ -700,7 +702,8 @@ static irqreturn_t imx_rxint(int irq, void *dev_id)
 		if (sport->port.ignore_status_mask & URXD_DUMMY_READ)
 			goto out;
 
-		tty_insert_flip_char(port, rx, flg);
+		if (tty_insert_flip_char(port, rx, flg) == 0)
+			sport->port.icount.buf_overrun++;
 	}
 
 out:
@@ -766,7 +769,6 @@ static irqreturn_t imx_int(int irq, void *dev_id)
 		writel(USR1_AWAKE, sport->port.membase + USR1);
 
 	if (sts2 & USR2_ORE) {
-		dev_err(sport->port.dev, "Rx FIFO overrun\n");
 		sport->port.icount.overrun++;
 		writel(USR2_ORE, sport->port.membase + USR2);
 	}
@@ -921,8 +923,13 @@ static void dma_rx_callback(void *data)
 	dev_dbg(sport->port.dev, "We get %d bytes.\n", count);
 
 	if (count) {
-		if (!(sport->port.ignore_status_mask & URXD_DUMMY_READ))
-			tty_insert_flip_string(port, sport->rx_buf, count);
+		if (!(sport->port.ignore_status_mask & URXD_DUMMY_READ)) {
+			int bytes = tty_insert_flip_string(port, sport->rx_buf,
+					count);
+
+			if (bytes != count)
+				sport->port.icount.buf_overrun++;
+		}
 		tty_flip_buffer_push(port);
 
 		start_rx_dma(sport);
@@ -1624,12 +1631,12 @@ imx_console_write(struct console *co, const char *s, unsigned int count)
 	int locked = 1;
 	int retval;
 
-	retval = clk_enable(sport->clk_per);
+	retval = clk_prepare_enable(sport->clk_per);
 	if (retval)
 		return;
-	retval = clk_enable(sport->clk_ipg);
+	retval = clk_prepare_enable(sport->clk_ipg);
 	if (retval) {
-		clk_disable(sport->clk_per);
+		clk_disable_unprepare(sport->clk_per);
 		return;
 	}
 
@@ -1668,8 +1675,8 @@ imx_console_write(struct console *co, const char *s, unsigned int count)
 	if (locked)
 		spin_unlock_irqrestore(&sport->port.lock, flags);
 
-	clk_disable(sport->clk_ipg);
-	clk_disable(sport->clk_per);
+	clk_disable_unprepare(sport->clk_ipg);
+	clk_disable_unprepare(sport->clk_per);
 }
 
 /*
@@ -1770,15 +1777,7 @@ imx_console_setup(struct console *co, char *options)
 
 	retval = uart_set_options(&sport->port, co, baud, parity, bits, flow);
 
-	clk_disable(sport->clk_ipg);
-	if (retval) {
-		clk_unprepare(sport->clk_ipg);
-		goto error_console;
-	}
-
-	retval = clk_prepare(sport->clk_per);
-	if (retval)
-		clk_disable_unprepare(sport->clk_ipg);
+	clk_disable_unprepare(sport->clk_ipg);
 
 error_console:
 	return retval;
@@ -1810,36 +1809,6 @@ static struct uart_driver imx_reg = {
 	.cons           = IMX_CONSOLE,
 };
 
-static int serial_imx_suspend(struct platform_device *dev, pm_message_t state)
-{
-	struct imx_port *sport = platform_get_drvdata(dev);
-	unsigned int val;
-
-	/* enable wakeup from i.MX UART */
-	val = readl(sport->port.membase + UCR3);
-	val |= UCR3_AWAKEN;
-	writel(val, sport->port.membase + UCR3);
-
-	uart_suspend_port(&imx_reg, &sport->port);
-
-	return 0;
-}
-
-static int serial_imx_resume(struct platform_device *dev)
-{
-	struct imx_port *sport = platform_get_drvdata(dev);
-	unsigned int val;
-
-	/* disable wakeup from i.MX UART */
-	val = readl(sport->port.membase + UCR3);
-	val &= ~UCR3_AWAKEN;
-	writel(val, sport->port.membase + UCR3);
-
-	uart_resume_port(&imx_reg, &sport->port);
-
-	return 0;
-}
-
 #ifdef CONFIG_OF
 /*
  * This function returns 1 iff pdev isn't a device instatiated by dt, 0 iff it
@@ -1901,7 +1870,7 @@ static int serial_imx_probe(struct platform_device *pdev)
 {
 	struct imx_port *sport;
 	void __iomem *base;
-	int ret = 0;
+	int ret = 0, reg;
 	struct resource *res;
 	int txirq, rxirq, rtsirq;
 
@@ -1956,6 +1925,19 @@ static int serial_imx_probe(struct platform_device *pdev)
 
 	sport->port.uartclk = clk_get_rate(sport->clk_per);
 
+	/* For register access, we only need to enable the ipg clock. */
+	ret = clk_prepare_enable(sport->clk_ipg);
+	if (ret)
+		return ret;
+
+	/* Disable interrupts before requesting them */
+	reg = readl_relaxed(sport->port.membase + UCR1);
+	reg &= ~(UCR1_ADEN | UCR1_TRDYEN | UCR1_IDEN | UCR1_RRDYEN |
+		 UCR1_TXMPTYEN | UCR1_RTSDEN);
+	writel_relaxed(reg, sport->port.membase + UCR1);
+
+	clk_disable_unprepare(sport->clk_ipg);
+
 	/*
 	 * Allocate the IRQ(s) i.MX1 has three interrupts whereas later
 	 * chips only have one interrupt.
@@ -1991,16 +1973,135 @@ static int serial_imx_remove(struct platform_device *pdev)
 	return uart_remove_one_port(&imx_reg, &sport->port);
 }
 
+static void serial_imx_restore_context(struct imx_port *sport)
+{
+	if (!sport->context_saved)
+		return;
+
+	writel(sport->saved_reg[4], sport->port.membase + UFCR);
+	writel(sport->saved_reg[5], sport->port.membase + UESC);
+	writel(sport->saved_reg[6], sport->port.membase + UTIM);
+	writel(sport->saved_reg[7], sport->port.membase + UBIR);
+	writel(sport->saved_reg[8], sport->port.membase + UBMR);
+	writel(sport->saved_reg[9], sport->port.membase + IMX21_UTS);
+	writel(sport->saved_reg[0], sport->port.membase + UCR1);
+	writel(sport->saved_reg[1] | UCR2_SRST, sport->port.membase + UCR2);
+	writel(sport->saved_reg[2], sport->port.membase + UCR3);
+	writel(sport->saved_reg[3], sport->port.membase + UCR4);
+	sport->context_saved = false;
+}
+
+static void serial_imx_save_context(struct imx_port *sport)
+{
+	/* Save necessary regs */
+	sport->saved_reg[0] = readl(sport->port.membase + UCR1);
+	sport->saved_reg[1] = readl(sport->port.membase + UCR2);
+	sport->saved_reg[2] = readl(sport->port.membase + UCR3);
+	sport->saved_reg[3] = readl(sport->port.membase + UCR4);
+	sport->saved_reg[4] = readl(sport->port.membase + UFCR);
+	sport->saved_reg[5] = readl(sport->port.membase + UESC);
+	sport->saved_reg[6] = readl(sport->port.membase + UTIM);
+	sport->saved_reg[7] = readl(sport->port.membase + UBIR);
+	sport->saved_reg[8] = readl(sport->port.membase + UBMR);
+	sport->saved_reg[9] = readl(sport->port.membase + IMX21_UTS);
+	sport->context_saved = true;
+}
+
+static void serial_imx_enable_wakeup(struct imx_port *sport, bool on)
+{
+	unsigned int val;
+
+	val = readl(sport->port.membase + UCR3);
+	if (on)
+		val |= UCR3_AWAKEN;
+	else
+		val &= ~UCR3_AWAKEN;
+	writel(val, sport->port.membase + UCR3);
+
+	val = readl(sport->port.membase + UCR1);
+	if (on)
+		val |= UCR1_RTSDEN;
+	else
+		val &= ~UCR1_RTSDEN;
+	writel(val, sport->port.membase + UCR1);
+}
+
+static int imx_serial_port_suspend_noirq(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct imx_port *sport = platform_get_drvdata(pdev);
+	int ret;
+
+	ret = clk_enable(sport->clk_ipg);
+	if (ret)
+		return ret;
+
+	serial_imx_save_context(sport);
+
+	clk_disable(sport->clk_ipg);
+
+	return 0;
+}
+
+static int imx_serial_port_resume_noirq(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct imx_port *sport = platform_get_drvdata(pdev);
+	int ret;
+
+	ret = clk_enable(sport->clk_ipg);
+	if (ret)
+		return ret;
+
+	serial_imx_restore_context(sport);
+
+	clk_disable(sport->clk_ipg);
+
+	return 0;
+}
+
+static int imx_serial_port_suspend(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct imx_port *sport = platform_get_drvdata(pdev);
+
+	/* enable wakeup from i.MX UART */
+	serial_imx_enable_wakeup(sport, true);
+
+	uart_suspend_port(&imx_reg, &sport->port);
+
+	return 0;
+}
+
+static int imx_serial_port_resume(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct imx_port *sport = platform_get_drvdata(pdev);
+
+	/* disable wakeup from i.MX UART */
+	serial_imx_enable_wakeup(sport, false);
+
+	uart_resume_port(&imx_reg, &sport->port);
+
+	return 0;
+}
+
+static const struct dev_pm_ops imx_serial_port_pm_ops = {
+	.suspend_noirq = imx_serial_port_suspend_noirq,
+	.resume_noirq = imx_serial_port_resume_noirq,
+	.suspend = imx_serial_port_suspend,
+	.resume = imx_serial_port_resume,
+};
+
 static struct platform_driver serial_imx_driver = {
 	.probe		= serial_imx_probe,
 	.remove		= serial_imx_remove,
 
-	.suspend	= serial_imx_suspend,
-	.resume		= serial_imx_resume,
 	.id_table	= imx_uart_devtype,
 	.driver		= {
 		.name	= "imx-uart",
 		.of_match_table = imx_uart_dt_ids,
+		.pm	= &imx_serial_port_pm_ops,
 	},
 };
 

drivers/tty/serial/lantiq.c

@@ -21,7 +21,6 @@
  */
 
 #include <linux/slab.h>
-#include <linux/module.h>
 #include <linux/ioport.h>
 #include <linux/init.h>
 #include <linux/console.h>
@@ -740,7 +739,6 @@ static const struct of_device_id ltq_asc_match[] = {
 	{ .compatible = DRVNAME },
 	{},
 };
-MODULE_DEVICE_TABLE(of, ltq_asc_match);
 
 static struct platform_driver lqasc_driver = {
 	.driver		= {
@@ -764,8 +762,4 @@ init_lqasc(void)
 
 	return ret;
 }
-
-module_init(init_lqasc);
-
-MODULE_DESCRIPTION("Lantiq serial port driver");
-MODULE_LICENSE("GPL");
+device_initcall(init_lqasc);

drivers/tty/serial/men_z135_uart.c

@@ -392,7 +392,6 @@ static irqreturn_t men_z135_intr(int irq, void *data)
 	struct men_z135_port *uart = (struct men_z135_port *)data;
 	struct uart_port *port = &uart->port;
 	bool handled = false;
-	unsigned long flags;
 	int irq_id;
 
 	uart->stat_reg = ioread32(port->membase + MEN_Z135_STAT_REG);
@@ -401,7 +400,7 @@ static irqreturn_t men_z135_intr(int irq, void *data)
 	if (!irq_id)
 		goto out;
 
-	spin_lock_irqsave(&port->lock, flags);
+	spin_lock(&port->lock);
 	/* It's save to write to IIR[7:6] RXC[9:8] */
 	iowrite8(irq_id, port->membase + MEN_Z135_STAT_REG);
 
@@ -427,7 +426,7 @@ static irqreturn_t men_z135_intr(int irq, void *data)
 		handled = true;
 	}
 
-	spin_unlock_irqrestore(&port->lock, flags);
+	spin_unlock(&port->lock);
 out:
 	return IRQ_RETVAL(handled);
 }
@@ -717,7 +716,7 @@ static void men_z135_set_termios(struct uart_port *port,
 
 	baud = uart_get_baud_rate(port, termios, old, 0, uart_freq / 16);
 
-	spin_lock(&port->lock);
+	spin_lock_irq(&port->lock);
 	if (tty_termios_baud_rate(termios))
 		tty_termios_encode_baud_rate(termios, baud, baud);
 
@@ -725,7 +724,7 @@ static void men_z135_set_termios(struct uart_port *port,
 	iowrite32(bd_reg, port->membase + MEN_Z135_BAUD_REG);
 
 	uart_update_timeout(port, termios->c_cflag, baud);
-	spin_unlock(&port->lock);
+	spin_unlock_irq(&port->lock);
 }
 
 static const char *men_z135_type(struct uart_port *port)
@@ -840,7 +839,6 @@ static int men_z135_probe(struct mcb_device *mdev,
 	uart->port.membase = NULL;
 	uart->mdev = mdev;
 
-	spin_lock_init(&uart->port.lock);
 	spin_lock_init(&uart->lock);
 
 	err = uart_add_one_port(&men_z135_driver, &uart->port);

drivers/tty/serial/mpc52xx_uart.c

@@ -239,8 +239,9 @@ static int mpc52xx_psc_tx_rdy(struct uart_port *port)
 
 static int mpc52xx_psc_tx_empty(struct uart_port *port)
 {
-	return in_be16(&PSC(port)->mpc52xx_psc_status)
-	    & MPC52xx_PSC_SR_TXEMP;
+	u16 sts = in_be16(&PSC(port)->mpc52xx_psc_status);
+
+	return (sts & MPC52xx_PSC_SR_TXEMP) ? TIOCSER_TEMT : 0;
 }
 
 static void mpc52xx_psc_start_tx(struct uart_port *port)

drivers/tty/serial/mxs-auart.c

@@ -100,6 +100,8 @@
 #define AUART_CTRL2_TXE				(1 << 8)
 #define AUART_CTRL2_UARTEN			(1 << 0)
 
+#define AUART_LINECTRL_BAUD_DIV_MAX		0x003fffc0
+#define AUART_LINECTRL_BAUD_DIV_MIN		0x000000ec
 #define AUART_LINECTRL_BAUD_DIVINT_SHIFT	16
 #define AUART_LINECTRL_BAUD_DIVINT_MASK		0xffff0000
 #define AUART_LINECTRL_BAUD_DIVINT(v)		(((v) & 0xffff) << 16)
@@ -659,7 +661,7 @@ static void mxs_auart_settermios(struct uart_port *u,
 {
 	struct mxs_auart_port *s = to_auart_port(u);
 	u32 bm, ctrl, ctrl2, div;
-	unsigned int cflag, baud;
+	unsigned int cflag, baud, baud_min, baud_max;
 
 	cflag = termios->c_cflag;
 
@@ -752,7 +754,9 @@ static void mxs_auart_settermios(struct uart_port *u,
 	}
 
 	/* set baud rate */
-	baud = uart_get_baud_rate(u, termios, old, 0, u->uartclk);
+	baud_min = DIV_ROUND_UP(u->uartclk * 32, AUART_LINECTRL_BAUD_DIV_MAX);
+	baud_max = u->uartclk * 32 / AUART_LINECTRL_BAUD_DIV_MIN;
+	baud = uart_get_baud_rate(u, termios, old, baud_min, baud_max);
 	div = u->uartclk * 32 / baud;
 	ctrl |= AUART_LINECTRL_BAUD_DIVFRAC(div & 0x3F);
 	ctrl |= AUART_LINECTRL_BAUD_DIVINT(div >> 6);
@@ -842,7 +846,7 @@ static irqreturn_t mxs_auart_irq_handle(int irq, void *context)
 	return IRQ_HANDLED;
 }
 
-static void mxs_auart_reset(struct uart_port *u)
+static void mxs_auart_reset_deassert(struct uart_port *u)
 {
 	int i;
 	unsigned int reg;
@@ -858,6 +862,30 @@ static void mxs_auart_reset(struct uart_port *u)
 	writel(AUART_CTRL0_CLKGATE, u->membase + AUART_CTRL0_CLR);
 }
 
+static void mxs_auart_reset_assert(struct uart_port *u)
+{
+	int i;
+	u32 reg;
+
+	reg = readl(u->membase + AUART_CTRL0);
+	/* if already in reset state, keep it untouched */
+	if (reg & AUART_CTRL0_SFTRST)
+		return;
+
+	writel(AUART_CTRL0_CLKGATE, u->membase + AUART_CTRL0_CLR);
+	writel(AUART_CTRL0_SFTRST, u->membase + AUART_CTRL0_SET);
+
+	for (i = 0; i < 1000; i++) {
+		reg = readl(u->membase + AUART_CTRL0);
+		/* reset is finished when the clock is gated */
+		if (reg & AUART_CTRL0_CLKGATE)
+			return;
+		udelay(10);
+	}
+
+	dev_err(u->dev, "Failed to reset the unit.");
+}
+
 static int mxs_auart_startup(struct uart_port *u)
 {
 	int ret;
@@ -867,7 +895,13 @@ static int mxs_auart_startup(struct uart_port *u)
 	if (ret)
 		return ret;
 
-	writel(AUART_CTRL0_CLKGATE, u->membase + AUART_CTRL0_CLR);
+	if (uart_console(u)) {
+		writel(AUART_CTRL0_CLKGATE, u->membase + AUART_CTRL0_CLR);
+	} else {
+		/* reset the unit to a well known state */
+		mxs_auart_reset_assert(u);
+		mxs_auart_reset_deassert(u);
+	}
 
 	writel(AUART_CTRL2_UARTEN, u->membase + AUART_CTRL2_SET);
 
@@ -899,12 +933,14 @@ static void mxs_auart_shutdown(struct uart_port *u)
 	if (auart_dma_enabled(s))
 		mxs_auart_dma_exit(s);
 
-	writel(AUART_CTRL2_UARTEN, u->membase + AUART_CTRL2_CLR);
-
-	writel(AUART_INTR_RXIEN | AUART_INTR_RTIEN | AUART_INTR_CTSMIEN,
-			u->membase + AUART_INTR_CLR);
-
-	writel(AUART_CTRL0_CLKGATE, u->membase + AUART_CTRL0_SET);
+	if (uart_console(u)) {
+		writel(AUART_CTRL2_UARTEN, u->membase + AUART_CTRL2_CLR);
+		writel(AUART_INTR_RXIEN | AUART_INTR_RTIEN | AUART_INTR_CTSMIEN,
+				u->membase + AUART_INTR_CLR);
+		writel(AUART_CTRL0_CLKGATE, u->membase + AUART_CTRL0_SET);
+	} else {
+		mxs_auart_reset_assert(u);
+	}
 
 	clk_disable_unprepare(s->clk);
 }
@@ -1291,7 +1327,7 @@ static int mxs_auart_probe(struct platform_device *pdev)
 
 	auart_port[s->port.line] = s;
 
-	mxs_auart_reset(&s->port);
+	mxs_auart_reset_deassert(&s->port);
 
 	ret = uart_add_one_port(&auart_driver, &s->port);
 	if (ret)

drivers/tty/serial/samsung.c

@@ -53,7 +53,6 @@
 #include "samsung.h"
 
 #if	defined(CONFIG_SERIAL_SAMSUNG_DEBUG) &&	\
-	defined(CONFIG_DEBUG_LL) &&		\
 	!defined(MODULE)
 
 extern void printascii(const char *);
@@ -295,15 +294,6 @@ static int s3c24xx_serial_start_tx_dma(struct s3c24xx_uart_port *ourport,
 	if (ourport->tx_mode != S3C24XX_TX_DMA)
 		enable_tx_dma(ourport);
 
-	while (xmit->tail & (dma_get_cache_alignment() - 1)) {
-		if (rd_regl(port, S3C2410_UFSTAT) & ourport->info->tx_fifofull)
-			return 0;
-		wr_regb(port, S3C2410_UTXH, xmit->buf[xmit->tail]);
-		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
-		port->icount.tx++;
-		count--;
-	}
-
 	dma->tx_size = count & ~(dma_get_cache_alignment() - 1);
 	dma->tx_transfer_addr = dma->tx_addr + xmit->tail;
 
@@ -342,7 +332,9 @@ static void s3c24xx_serial_start_next_tx(struct s3c24xx_uart_port *ourport)
 		return;
 	}
 
-	if (!ourport->dma || !ourport->dma->tx_chan || count < port->fifosize)
+	if (!ourport->dma || !ourport->dma->tx_chan ||
+	    count < ourport->min_dma_size ||
+	    xmit->tail & (dma_get_cache_alignment() - 1))
 		s3c24xx_serial_start_tx_pio(ourport);
 	else
 		s3c24xx_serial_start_tx_dma(ourport, count);
@@ -736,15 +728,20 @@ static irqreturn_t s3c24xx_serial_tx_chars(int irq, void *id)
 	struct uart_port *port = &ourport->port;
 	struct circ_buf *xmit = &port->state->xmit;
 	unsigned long flags;
-	int count;
+	int count, dma_count = 0;
 
 	spin_lock_irqsave(&port->lock, flags);
 
 	count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
 
-	if (ourport->dma && ourport->dma->tx_chan && count >= port->fifosize) {
-		s3c24xx_serial_start_tx_dma(ourport, count);
-		goto out;
+	if (ourport->dma && ourport->dma->tx_chan &&
+	    count >= ourport->min_dma_size) {
+		int align = dma_get_cache_alignment() -
+			(xmit->tail & (dma_get_cache_alignment() - 1));
+		if (count-align >= ourport->min_dma_size) {
+			dma_count = count-align;
+			count = align;
+		}
 	}
 
 	if (port->x_char) {
@@ -765,14 +762,24 @@ static irqreturn_t s3c24xx_serial_tx_chars(int irq, void *id)
 
 	/* try and drain the buffer... */
 
-	count = port->fifosize;
-	while (!uart_circ_empty(xmit) && count-- > 0) {
+	if (count > port->fifosize) {
+		count = port->fifosize;
+		dma_count = 0;
+	}
+
+	while (!uart_circ_empty(xmit) && count > 0) {
 		if (rd_regl(port, S3C2410_UFSTAT) & ourport->info->tx_fifofull)
 			break;
 
 		wr_regb(port, S3C2410_UTXH, xmit->buf[xmit->tail]);
 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 		port->icount.tx++;
+		count--;
+	}
+
+	if (!count && dma_count) {
+		s3c24xx_serial_start_tx_dma(ourport, dma_count);
+		goto out;
 	}
 
 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) {
@@ -1838,6 +1845,13 @@ static int s3c24xx_serial_probe(struct platform_device *pdev)
 	else if (ourport->info->fifosize)
 		ourport->port.fifosize = ourport->info->fifosize;
 
+	/*
+	 * DMA transfers must be aligned at least to cache line size,
+	 * so find minimal transfer size suitable for DMA mode
+	 */
+	ourport->min_dma_size = max_t(int, ourport->port.fifosize,
+				    dma_get_cache_alignment());
+
 	probe_index++;
 
 	dbg("%s: initialising port %p...\n", __func__, ourport);

drivers/tty/serial/samsung.h

@@ -82,6 +82,7 @@ struct s3c24xx_uart_port {
 	unsigned char			tx_claimed;
 	unsigned int			pm_level;
 	unsigned long			baudclk_rate;
+	unsigned int			min_dma_size;
 
 	unsigned int			rx_irq;
 	unsigned int			tx_irq;

drivers/tty/serial/sc16is7xx.c

@@ -11,6 +11,8 @@
  *
  */
 
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
 #include <linux/bitops.h>
 #include <linux/clk.h>
 #include <linux/delay.h>
@@ -29,6 +31,7 @@
 #include <linux/uaccess.h>
 
 #define SC16IS7XX_NAME			"sc16is7xx"
+#define SC16IS7XX_MAX_DEVS		8
 
 /* SC16IS7XX register definitions */
 #define SC16IS7XX_RHR_REG		(0x00) /* RX FIFO */
@@ -312,14 +315,14 @@ struct sc16is7xx_one_config {
 
 struct sc16is7xx_one {
 	struct uart_port		port;
+	u8				line;
 	struct kthread_work		tx_work;
 	struct kthread_work		reg_work;
 	struct sc16is7xx_one_config	config;
 };
 
 struct sc16is7xx_port {
-	struct uart_driver		uart;
-	struct sc16is7xx_devtype	*devtype;
+	const struct sc16is7xx_devtype	*devtype;
 	struct regmap			*regmap;
 	struct clk			*clk;
 #ifdef CONFIG_GPIOLIB
@@ -332,16 +335,31 @@ struct sc16is7xx_port {
 	struct sc16is7xx_one		p[0];
 };
 
+static unsigned long sc16is7xx_lines;
+
+static struct uart_driver sc16is7xx_uart = {
+	.owner		= THIS_MODULE,
+	.dev_name	= "ttySC",
+	.nr		= SC16IS7XX_MAX_DEVS,
+};
+
 #define to_sc16is7xx_port(p,e)	((container_of((p), struct sc16is7xx_port, e)))
 #define to_sc16is7xx_one(p,e)	((container_of((p), struct sc16is7xx_one, e)))
 
+static int sc16is7xx_line(struct uart_port *port)
+{
+	struct sc16is7xx_one *one = to_sc16is7xx_one(port, port);
+
+	return one->line;
+}
+
 static u8 sc16is7xx_port_read(struct uart_port *port, u8 reg)
 {
 	struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
 	unsigned int val = 0;
+	const u8 line = sc16is7xx_line(port);
 
-	regmap_read(s->regmap,
-		    (reg << SC16IS7XX_REG_SHIFT) | port->line, &val);
+	regmap_read(s->regmap, (reg << SC16IS7XX_REG_SHIFT) | line, &val);
 
 	return val;
 }
@@ -349,15 +367,16 @@ static u8 sc16is7xx_port_read(struct uart_port *port, u8 reg)
 static void sc16is7xx_port_write(struct uart_port *port, u8 reg, u8 val)
 {
 	struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
+	const u8 line = sc16is7xx_line(port);
 
-	regmap_write(s->regmap,
-		     (reg << SC16IS7XX_REG_SHIFT) | port->line, val);
+	regmap_write(s->regmap, (reg << SC16IS7XX_REG_SHIFT) | line, val);
 }
 
 static void sc16is7xx_fifo_read(struct uart_port *port, unsigned int rxlen)
 {
 	struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
-	u8 addr = (SC16IS7XX_RHR_REG << SC16IS7XX_REG_SHIFT) | port->line;
+	const u8 line = sc16is7xx_line(port);
+	u8 addr = (SC16IS7XX_RHR_REG << SC16IS7XX_REG_SHIFT) | line;
 
 	regcache_cache_bypass(s->regmap, true);
 	regmap_raw_read(s->regmap, addr, s->buf, rxlen);
@@ -367,7 +386,8 @@ static void sc16is7xx_fifo_read(struct uart_port *port, unsigned int rxlen)
 static void sc16is7xx_fifo_write(struct uart_port *port, u8 to_send)
 {
 	struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
-	u8 addr = (SC16IS7XX_THR_REG << SC16IS7XX_REG_SHIFT) | port->line;
+	const u8 line = sc16is7xx_line(port);
+	u8 addr = (SC16IS7XX_THR_REG << SC16IS7XX_REG_SHIFT) | line;
 
 	regcache_cache_bypass(s->regmap, true);
 	regmap_raw_write(s->regmap, addr, s->buf, to_send);
@@ -378,12 +398,24 @@ static void sc16is7xx_port_update(struct uart_port *port, u8 reg,
 				  u8 mask, u8 val)
 {
 	struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
+	const u8 line = sc16is7xx_line(port);
 
-	regmap_update_bits(s->regmap,
-			   (reg << SC16IS7XX_REG_SHIFT) | port->line,
+	regmap_update_bits(s->regmap, (reg << SC16IS7XX_REG_SHIFT) | line,
 			   mask, val);
 }
 
+static int sc16is7xx_alloc_line(void)
+{
+	int i;
+
+	BUILD_BUG_ON(SC16IS7XX_MAX_DEVS > BITS_PER_LONG);
+
+	for (i = 0; i < SC16IS7XX_MAX_DEVS; i++)
+		if (!test_and_set_bit(i, &sc16is7xx_lines))
+			break;
+
+	return i;
+}
 
 static void sc16is7xx_power(struct uart_port *port, int on)
 {
@@ -508,7 +540,7 @@ static void sc16is7xx_handle_rx(struct uart_port *port, unsigned int rxlen,
 
 	if (unlikely(rxlen >= sizeof(s->buf))) {
 		dev_warn_ratelimited(port->dev,
-				     "Port %i: Possible RX FIFO overrun: %d\n",
+				     "ttySC%i: Possible RX FIFO overrun: %d\n",
 				     port->line, rxlen);
 		port->icount.buf_overrun++;
 		/* Ensure sanity of RX level */
@@ -649,7 +681,7 @@ static void sc16is7xx_port_irq(struct sc16is7xx_port *s, int portno)
 			break;
 		default:
 			dev_err_ratelimited(port->dev,
-					    "Port %i: Unexpected interrupt: %x",
+					    "ttySC%i: Unexpected interrupt: %x",
 					    port->line, iir);
 			break;
 		}
@@ -661,7 +693,7 @@ static void sc16is7xx_ist(struct kthread_work *ws)
 	struct sc16is7xx_port *s = to_sc16is7xx_port(ws, irq_work);
 	int i;
 
-	for (i = 0; i < s->uart.nr; ++i)
+	for (i = 0; i < s->devtype->nr_uart; ++i)
 		sc16is7xx_port_irq(s, i);
 }
 
@@ -1099,7 +1131,7 @@ static int sc16is7xx_gpio_direction_output(struct gpio_chip *chip,
 #endif
 
 static int sc16is7xx_probe(struct device *dev,
-			   struct sc16is7xx_devtype *devtype,
+			   const struct sc16is7xx_devtype *devtype,
 			   struct regmap *regmap, int irq, unsigned long flags)
 {
 	struct sched_param sched_param = { .sched_priority = MAX_RT_PRIO / 2 };
@@ -1134,23 +1166,13 @@ static int sc16is7xx_probe(struct device *dev,
 	s->devtype = devtype;
 	dev_set_drvdata(dev, s);
 
-	/* Register UART driver */
-	s->uart.owner		= THIS_MODULE;
-	s->uart.dev_name	= "ttySC";
-	s->uart.nr		= devtype->nr_uart;
-	ret = uart_register_driver(&s->uart);
-	if (ret) {
-		dev_err(dev, "Registering UART driver failed\n");
-		goto out_clk;
-	}
-
 	init_kthread_worker(&s->kworker);
 	init_kthread_work(&s->irq_work, sc16is7xx_ist);
 	s->kworker_task = kthread_run(kthread_worker_fn, &s->kworker,
 				      "sc16is7xx");
 	if (IS_ERR(s->kworker_task)) {
 		ret = PTR_ERR(s->kworker_task);
-		goto out_uart;
+		goto out_clk;
 	}
 	sched_setscheduler(s->kworker_task, SCHED_FIFO, &sched_param);
 
@@ -1174,8 +1196,8 @@ static int sc16is7xx_probe(struct device *dev,
 #endif
 
 	for (i = 0; i < devtype->nr_uart; ++i) {
+		s->p[i].line		= i;
 		/* Initialize port data */
-		s->p[i].port.line	= i;
 		s->p[i].port.dev	= dev;
 		s->p[i].port.irq	= irq;
 		s->p[i].port.type	= PORT_SC16IS7XX;
@@ -1185,6 +1207,12 @@ static int sc16is7xx_probe(struct device *dev,
 		s->p[i].port.uartclk	= freq;
 		s->p[i].port.rs485_config = sc16is7xx_config_rs485;
 		s->p[i].port.ops	= &sc16is7xx_ops;
+		s->p[i].port.line	= sc16is7xx_alloc_line();
+		if (s->p[i].port.line >= SC16IS7XX_MAX_DEVS) {
+			ret = -ENOMEM;
+			goto out_ports;
+		}
+
 		/* Disable all interrupts */
 		sc16is7xx_port_write(&s->p[i].port, SC16IS7XX_IER_REG, 0);
 		/* Disable TX/RX */
@@ -1195,7 +1223,7 @@ static int sc16is7xx_probe(struct device *dev,
 		init_kthread_work(&s->p[i].tx_work, sc16is7xx_tx_proc);
 		init_kthread_work(&s->p[i].reg_work, sc16is7xx_reg_proc);
 		/* Register port */
-		uart_add_one_port(&s->uart, &s->p[i].port);
+		uart_add_one_port(&sc16is7xx_uart, &s->p[i].port);
 		/* Go to suspend mode */
 		sc16is7xx_power(&s->p[i].port, 0);
 	}
@@ -1206,8 +1234,11 @@ static int sc16is7xx_probe(struct device *dev,
 	if (!ret)
 		return 0;
 
-	for (i = 0; i < s->uart.nr; i++)
-		uart_remove_one_port(&s->uart, &s->p[i].port);
+out_ports:
+	for (i--; i >= 0; i--) {
+		uart_remove_one_port(&sc16is7xx_uart, &s->p[i].port);
+		clear_bit(s->p[i].port.line, &sc16is7xx_lines);
+	}
 
 #ifdef CONFIG_GPIOLIB
 	if (devtype->nr_gpio)
@@ -1217,9 +1248,6 @@ out_thread:
 #endif
 	kthread_stop(s->kworker_task);
 
-out_uart:
-	uart_unregister_driver(&s->uart);
-
 out_clk:
 	if (!IS_ERR(s->clk))
 		clk_disable_unprepare(s->clk);
@@ -1237,15 +1265,15 @@ static int sc16is7xx_remove(struct device *dev)
 		gpiochip_remove(&s->gpio);
 #endif
 
-	for (i = 0; i < s->uart.nr; i++) {
-		uart_remove_one_port(&s->uart, &s->p[i].port);
+	for (i = 0; i < s->devtype->nr_uart; i++) {
+		uart_remove_one_port(&sc16is7xx_uart, &s->p[i].port);
+		clear_bit(s->p[i].port.line, &sc16is7xx_lines);
 		sc16is7xx_power(&s->p[i].port, 0);
 	}
 
 	flush_kthread_worker(&s->kworker);
 	kthread_stop(s->kworker_task);
 
-	uart_unregister_driver(&s->uart);
 	if (!IS_ERR(s->clk))
 		clk_disable_unprepare(s->clk);
 
@@ -1275,7 +1303,7 @@ static struct regmap_config regcfg = {
 #ifdef CONFIG_SERIAL_SC16IS7XX_SPI
 static int sc16is7xx_spi_probe(struct spi_device *spi)
 {
-	struct sc16is7xx_devtype *devtype;
+	const struct sc16is7xx_devtype *devtype;
 	unsigned long flags = 0;
 	struct regmap *regmap;
 	int ret;
@@ -1344,7 +1372,7 @@ MODULE_ALIAS("spi:sc16is7xx");
 static int sc16is7xx_i2c_probe(struct i2c_client *i2c,
 			       const struct i2c_device_id *id)
 {
-	struct sc16is7xx_devtype *devtype;
+	const struct sc16is7xx_devtype *devtype;
 	unsigned long flags = 0;
 	struct regmap *regmap;
 
@@ -1385,7 +1413,6 @@ MODULE_DEVICE_TABLE(i2c, sc16is7xx_i2c_id_table);
 static struct i2c_driver sc16is7xx_i2c_uart_driver = {
 	.driver = {
 		.name		= SC16IS7XX_NAME,
-		.owner		= THIS_MODULE,
 		.of_match_table	= of_match_ptr(sc16is7xx_dt_ids),
 	},
 	.probe		= sc16is7xx_i2c_probe,
@@ -1398,7 +1425,14 @@ MODULE_ALIAS("i2c:sc16is7xx");
 
 static int __init sc16is7xx_init(void)
 {
-	int ret = 0;
+	int ret;
+
+	ret = uart_register_driver(&sc16is7xx_uart);
+	if (ret) {
+		pr_err("Registering UART driver failed\n");
+		return ret;
+	}
+
 #ifdef CONFIG_SERIAL_SC16IS7XX_I2C
 	ret = i2c_add_driver(&sc16is7xx_i2c_uart_driver);
 	if (ret < 0) {
@@ -1427,6 +1461,7 @@ static void __exit sc16is7xx_exit(void)
 #ifdef CONFIG_SERIAL_SC16IS7XX_SPI
 	spi_unregister_driver(&sc16is7xx_spi_uart_driver);
 #endif
+	uart_unregister_driver(&sc16is7xx_uart);
 }
 module_exit(sc16is7xx_exit);
 

drivers/tty/serial/serial_core.c

@@ -1377,7 +1377,6 @@ static void uart_close(struct tty_struct *tty, struct file *filp)
 	struct uart_state *state = tty->driver_data;
 	struct tty_port *port;
 	struct uart_port *uport;
-	unsigned long flags;
 
 	if (!state) {
 		struct uart_driver *drv = tty->driver->driver_state;
@@ -1403,10 +1402,9 @@ static void uart_close(struct tty_struct *tty, struct file *filp)
 	 * disable the receive line status interrupts.
 	 */
 	if (port->flags & ASYNC_INITIALIZED) {
-		unsigned long flags;
-		spin_lock_irqsave(&uport->lock, flags);
+		spin_lock_irq(&uport->lock);
 		uport->ops->stop_rx(uport);
-		spin_unlock_irqrestore(&uport->lock, flags);
+		spin_unlock_irq(&uport->lock);
 		/*
 		 * Before we drop DTR, make sure the UART transmitter
 		 * has completely drained; this is especially
@@ -1419,17 +1417,17 @@ static void uart_close(struct tty_struct *tty, struct file *filp)
 	uart_shutdown(tty, state);
 	tty_port_tty_set(port, NULL);
 
-	spin_lock_irqsave(&port->lock, flags);
+	spin_lock_irq(&port->lock);
 
 	if (port->blocked_open) {
-		spin_unlock_irqrestore(&port->lock, flags);
+		spin_unlock_irq(&port->lock);
 		if (port->close_delay)
 			msleep_interruptible(jiffies_to_msecs(port->close_delay));
-		spin_lock_irqsave(&port->lock, flags);
+		spin_lock_irq(&port->lock);
 	} else if (!uart_console(uport)) {
-		spin_unlock_irqrestore(&port->lock, flags);
+		spin_unlock_irq(&port->lock);
 		uart_change_pm(state, UART_PM_STATE_OFF);
-		spin_lock_irqsave(&port->lock, flags);
+		spin_lock_irq(&port->lock);
 	}
 
 	/*
@@ -1437,7 +1435,7 @@ static void uart_close(struct tty_struct *tty, struct file *filp)
 	 */
 	clear_bit(ASYNCB_NORMAL_ACTIVE, &port->flags);
 	clear_bit(ASYNCB_CLOSING, &port->flags);
-	spin_unlock_irqrestore(&port->lock, flags);
+	spin_unlock_irq(&port->lock);
 	wake_up_interruptible(&port->open_wait);
 	wake_up_interruptible(&port->close_wait);
 
@@ -1532,11 +1530,6 @@ static void uart_hangup(struct tty_struct *tty)
 	mutex_unlock(&port->mutex);
 }
 
-static int uart_port_activate(struct tty_port *port, struct tty_struct *tty)
-{
-	return 0;
-}
-
 static void uart_port_shutdown(struct tty_port *port)
 {
 	struct uart_state *state = container_of(port, struct uart_state, port);
@@ -2379,8 +2372,6 @@ static const struct tty_operations uart_ops = {
 };
 
 static const struct tty_port_operations uart_port_ops = {
-	.activate	= uart_port_activate,
-	.shutdown	= uart_port_shutdown,
 	.carrier_raised = uart_carrier_raised,
 	.dtr_rts	= uart_dtr_rts,
 };

drivers/tty/serial/sirfsoc_uart.c

@@ -413,7 +413,6 @@ sirfsoc_uart_pio_rx_chars(struct uart_port *port, unsigned int max_rx_count)
 			break;
 	}
 
-	sirfport->rx_io_count += rx_count;
 	port->icount.rx += rx_count;
 
 	return rx_count;
@@ -600,7 +599,6 @@ static void sirfsoc_uart_start_next_rx_dma(struct uart_port *port)
 	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
 	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
 	struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
-	sirfport->rx_io_count = 0;
 	wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
 		rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) &
 		~SIRFUART_IO_MODE);
@@ -632,31 +630,6 @@ static void sirfsoc_uart_start_next_rx_dma(struct uart_port *port)
 				sirfport->uart_reg->uart_type));
 }
 
-static void sirfsoc_uart_start_rx(struct uart_port *port)
-{
-	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
-	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
-	struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
-
-	sirfport->rx_io_count = 0;
-	wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_RESET);
-	wr_regl(port, ureg->sirfsoc_rx_fifo_op, 0);
-	wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_START);
-	if (sirfport->rx_dma_chan)
-		sirfsoc_uart_start_next_rx_dma(port);
-	else {
-		if (!sirfport->is_atlas7)
-			wr_regl(port, ureg->sirfsoc_int_en_reg,
-				rd_regl(port, ureg->sirfsoc_int_en_reg) |
-				SIRFUART_RX_IO_INT_EN(uint_en,
-					sirfport->uart_reg->uart_type));
-		else
-			wr_regl(port, ureg->sirfsoc_int_en_reg,
-				SIRFUART_RX_IO_INT_EN(uint_en,
-					sirfport->uart_reg->uart_type));
-	}
-}
-
 static unsigned int
 sirfsoc_usp_calc_sample_div(unsigned long set_rate,
 		unsigned long ioclk_rate, unsigned long *sample_reg)
@@ -850,7 +823,6 @@ static void sirfsoc_uart_set_termios(struct uart_port *port,
 	rx_time_out = SIRFSOC_UART_RX_TIMEOUT(set_baud, 20000);
 	rx_time_out = SIRFUART_RECV_TIMEOUT_VALUE(rx_time_out);
 	txfifo_op_reg = rd_regl(port, ureg->sirfsoc_tx_fifo_op);
-	wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_STOP);
 	wr_regl(port, ureg->sirfsoc_tx_fifo_op,
 			(txfifo_op_reg & ~SIRFUART_FIFO_START));
 	if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
@@ -886,9 +858,13 @@ static void sirfsoc_uart_set_termios(struct uart_port *port,
 	else
 		wr_regl(port, ureg->sirfsoc_tx_dma_io_ctrl, SIRFUART_IO_MODE);
 	if (sirfport->rx_dma_chan)
-		wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl, SIRFUART_DMA_MODE);
+		wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
+			rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) &
+			~SIRFUART_IO_MODE);
 	else
-		wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl, SIRFUART_IO_MODE);
+		wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
+			rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) |
+			SIRFUART_IO_MODE);
 	sirfport->rx_period_time = 20000000;
 	/* Reset Rx/Tx FIFO Threshold level for proper baudrate */
 	if (set_baud < 1000000)
@@ -902,7 +878,6 @@ static void sirfsoc_uart_set_termios(struct uart_port *port,
 	txfifo_op_reg |= SIRFUART_FIFO_START;
 	wr_regl(port, ureg->sirfsoc_tx_fifo_op, txfifo_op_reg);
 	uart_update_timeout(port, termios->c_cflag, set_baud);
-	sirfsoc_uart_start_rx(port);
 	wr_regl(port, ureg->sirfsoc_tx_rx_en, SIRFUART_TX_EN | SIRFUART_RX_EN);
 	spin_unlock_irqrestore(&port->lock, flags);
 }
@@ -921,6 +896,7 @@ static int sirfsoc_uart_startup(struct uart_port *port)
 {
 	struct sirfsoc_uart_port *sirfport	= to_sirfport(port);
 	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
+	struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
 	unsigned int index			= port->line;
 	int ret;
 	irq_modify_status(port->irq, IRQ_NOREQUEST, IRQ_NOAUTOEN);
@@ -958,9 +934,9 @@ static int sirfsoc_uart_startup(struct uart_port *port)
 	wr_regl(port, ureg->sirfsoc_rx_fifo_ctrl, SIRFUART_FIFO_THD(port));
 	if (sirfport->rx_dma_chan)
 		wr_regl(port, ureg->sirfsoc_rx_fifo_level_chk,
-			SIRFUART_RX_FIFO_CHK_SC(port->line, 0x4) |
-			SIRFUART_RX_FIFO_CHK_LC(port->line, 0xe) |
-			SIRFUART_RX_FIFO_CHK_HC(port->line, 0x1b));
+			SIRFUART_RX_FIFO_CHK_SC(port->line, 0x1) |
+			SIRFUART_RX_FIFO_CHK_LC(port->line, 0x2) |
+			SIRFUART_RX_FIFO_CHK_HC(port->line, 0x4));
 	if (sirfport->tx_dma_chan) {
 		sirfport->tx_dma_state = TX_DMA_IDLE;
 		wr_regl(port, ureg->sirfsoc_tx_fifo_level_chk,
@@ -981,16 +957,41 @@ static int sirfsoc_uart_startup(struct uart_port *port)
 			goto init_rx_err;
 		}
 	}
-	enable_irq(port->irq);
+	if (sirfport->uart_reg->uart_type == SIRF_REAL_UART &&
+		sirfport->rx_dma_chan)
+		wr_regl(port, ureg->sirfsoc_swh_dma_io,
+			SIRFUART_CLEAR_RX_ADDR_EN);
+	if (sirfport->uart_reg->uart_type == SIRF_USP_UART &&
+			sirfport->rx_dma_chan)
+		wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
+			rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) |
+			SIRFSOC_USP_FRADDR_CLR_EN);
 	if (sirfport->rx_dma_chan && !sirfport->is_hrt_enabled) {
 		sirfport->is_hrt_enabled = true;
 		sirfport->rx_period_time = 20000000;
+		sirfport->rx_last_pos = -1;
+		sirfport->pio_fetch_cnt = 0;
 		sirfport->rx_dma_items.xmit.tail =
 			sirfport->rx_dma_items.xmit.head = 0;
 		hrtimer_start(&sirfport->hrt,
 			ns_to_ktime(sirfport->rx_period_time),
 			HRTIMER_MODE_REL);
 	}
+	wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_START);
+	if (sirfport->rx_dma_chan)
+		sirfsoc_uart_start_next_rx_dma(port);
+	else {
+		if (!sirfport->is_atlas7)
+			wr_regl(port, ureg->sirfsoc_int_en_reg,
+				rd_regl(port, ureg->sirfsoc_int_en_reg) |
+				SIRFUART_RX_IO_INT_EN(uint_en,
+					sirfport->uart_reg->uart_type));
+		else
+			wr_regl(port, ureg->sirfsoc_int_en_reg,
+				SIRFUART_RX_IO_INT_EN(uint_en,
+					sirfport->uart_reg->uart_type));
+	}
+	enable_irq(port->irq);
 
 	return 0;
 init_rx_err:
@@ -1003,6 +1004,9 @@ static void sirfsoc_uart_shutdown(struct uart_port *port)
 {
 	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
 	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
+	struct circ_buf *xmit;
+
+	xmit = &sirfport->rx_dma_items.xmit;
 	if (!sirfport->is_atlas7)
 		wr_regl(port, ureg->sirfsoc_int_en_reg, 0);
 	else
@@ -1019,8 +1023,10 @@ static void sirfsoc_uart_shutdown(struct uart_port *port)
 	if (sirfport->tx_dma_chan)
 		sirfport->tx_dma_state = TX_DMA_IDLE;
 	if (sirfport->rx_dma_chan && sirfport->is_hrt_enabled) {
-		while ((rd_regl(port, ureg->sirfsoc_rx_fifo_status) &
-			SIRFUART_RX_FIFO_MASK) > 0)
+		while (((rd_regl(port, ureg->sirfsoc_rx_fifo_status) &
+			SIRFUART_RX_FIFO_MASK) > sirfport->pio_fetch_cnt) &&
+			!CIRC_CNT(xmit->head, xmit->tail,
+			SIRFSOC_RX_DMA_BUF_SIZE))
 			;
 		sirfport->is_hrt_enabled = false;
 		hrtimer_cancel(&sirfport->hrt);
@@ -1169,6 +1175,8 @@ static enum hrtimer_restart
 	struct tty_struct *tty;
 	struct sirfsoc_register *ureg;
 	struct circ_buf *xmit;
+	struct sirfsoc_fifo_status *ufifo_st;
+	int max_pio_cnt;
 
 	sirfport = container_of(hrt, struct sirfsoc_uart_port, hrt);
 	port = &sirfport->port;
@@ -1176,9 +1184,16 @@ static enum hrtimer_restart
 	tty = port->state->port.tty;
 	ureg = &sirfport->uart_reg->uart_reg;
 	xmit = &sirfport->rx_dma_items.xmit;
+	ufifo_st = &sirfport->uart_reg->fifo_status;
+
 	dmaengine_tx_status(sirfport->rx_dma_chan,
-		sirfport->rx_dma_items.cookie, &tx_state);
-	xmit->head = SIRFSOC_RX_DMA_BUF_SIZE - tx_state.residue;
+			sirfport->rx_dma_items.cookie, &tx_state);
+	if (SIRFSOC_RX_DMA_BUF_SIZE - tx_state.residue !=
+		sirfport->rx_last_pos) {
+		xmit->head = SIRFSOC_RX_DMA_BUF_SIZE - tx_state.residue;
+		sirfport->rx_last_pos = xmit->head;
+		sirfport->pio_fetch_cnt = 0;
+	}
 	count = CIRC_CNT_TO_END(xmit->head, xmit->tail,
 			SIRFSOC_RX_DMA_BUF_SIZE);
 	while (count > 0) {
@@ -1200,23 +1215,38 @@ static enum hrtimer_restart
 	 */
 	if (!inserted && !count &&
 		((rd_regl(port, ureg->sirfsoc_rx_fifo_status) &
-		SIRFUART_RX_FIFO_MASK) > 0)) {
+		SIRFUART_RX_FIFO_MASK) > sirfport->pio_fetch_cnt)) {
+		dmaengine_pause(sirfport->rx_dma_chan);
 		/* switch to pio mode */
 		wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
 			rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) |
 			SIRFUART_IO_MODE);
-		while ((rd_regl(port, ureg->sirfsoc_rx_fifo_status) &
-			SIRFUART_RX_FIFO_MASK) > 0) {
-			if (sirfsoc_uart_pio_rx_chars(port, 16) > 0)
-				tty_flip_buffer_push(tty->port);
+		/*
+		 * UART controller SWH_DMA_IO register have CLEAR_RX_ADDR_EN
+		 * When found changing I/O to DMA mode, it clears
+		 * two low bits of read point;
+		 * USP have similar FRADDR_CLR_EN bit in USP_RX_DMA_IO_CTRL.
+		 * Fetch data out from rxfifo into DMA buffer in PIO mode,
+		 * while switch back to DMA mode, the data fetched will override
+		 * by DMA, as hardware have a strange behaviour:
+		 * after switch back to DMA mode, check rxfifo status it will
+		 * be the number PIO fetched, so record the fetched data count
+		 * to avoid the repeated fetch
+		 */
+		max_pio_cnt = 3;
+		while (!(rd_regl(port, ureg->sirfsoc_rx_fifo_status) &
+			ufifo_st->ff_empty(port)) && max_pio_cnt--) {
+			xmit->buf[xmit->head] =
+				rd_regl(port, ureg->sirfsoc_rx_fifo_data);
+			xmit->head = (xmit->head + 1) &
+					(SIRFSOC_RX_DMA_BUF_SIZE - 1);
+			sirfport->pio_fetch_cnt++;
 		}
-		wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_RESET);
-		wr_regl(port, ureg->sirfsoc_rx_fifo_op, 0);
-		wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_START);
 		/* switch back to dma mode */
 		wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
 			rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) &
 			~SIRFUART_IO_MODE);
+		dmaengine_resume(sirfport->rx_dma_chan);
 	}
 next_hrt:
 	hrtimer_forward_now(hrt, ns_to_ktime(sirfport->rx_period_time));
@@ -1239,7 +1269,7 @@ static int sirfsoc_uart_probe(struct platform_device *pdev)
 	struct resource *res;
 	int ret;
 	struct dma_slave_config slv_cfg = {
-		.src_maxburst = 2,
+		.src_maxburst = 1,
 	};
 	struct dma_slave_config tx_slv_cfg = {
 		.dst_maxburst = 2,

drivers/tty/serial/sirfsoc_uart.h

@@ -296,6 +296,7 @@ struct sirfsoc_uart_register sirfsoc_uart = {
 #define SIRFUART_DMA_MODE			0x0
 #define SIRFUART_RX_DMA_FLUSH			0x4
 
+#define SIRFUART_CLEAR_RX_ADDR_EN		0x2
 /* Baud Rate Calculation */
 #define SIRF_USP_MIN_SAMPLE_DIV			0x1
 #define SIRF_MIN_SAMPLE_DIV			0xf
@@ -325,6 +326,7 @@ struct sirfsoc_uart_register sirfsoc_uart = {
 #define SIRFSOC_USP_ASYNC_DIV2_MASK		0x3f
 #define SIRFSOC_USP_ASYNC_DIV2_OFFSET		16
 #define SIRFSOC_USP_LOOP_BACK_CTRL		BIT(2)
+#define SIRFSOC_USP_FRADDR_CLR_EN		BIT(1)
 /* USP-UART Common */
 #define SIRFSOC_UART_RX_TIMEOUT(br, to)	(((br) * (((to) + 999) / 1000)) / 1000)
 #define SIRFUART_RECV_TIMEOUT_VALUE(x)	\
@@ -421,7 +423,6 @@ struct sirfsoc_uart_port {
 	struct dma_chan			*tx_dma_chan;
 	dma_addr_t			tx_dma_addr;
 	struct dma_async_tx_descriptor	*tx_dma_desc;
-	unsigned int			rx_io_count;
 	unsigned long			transfer_size;
 	enum sirfsoc_tx_state		tx_dma_state;
 	unsigned int			cts_gpio;
@@ -431,6 +432,8 @@ struct sirfsoc_uart_port {
 	struct hrtimer			hrt;
 	bool				is_hrt_enabled;
 	unsigned long			rx_period_time;
+	unsigned long			rx_last_pos;
+	unsigned long			pio_fetch_cnt;
 };
 
 /* Register Access Control */

drivers/tty/serial/sn_console.c

@@ -42,7 +42,7 @@
 #include <linux/tty_flip.h>
 #include <linux/serial.h>
 #include <linux/console.h>
-#include <linux/module.h>
+#include <linux/init.h>
 #include <linux/sysrq.h>
 #include <linux/circ_buf.h>
 #include <linux/serial_reg.h>
@@ -659,7 +659,7 @@ static void sn_sal_timer_poll(unsigned long data)
  * @port: Our sn_cons_port (which contains the uart port)
  *
  * So this is used by sn_sal_serial_console_init (early on, before we're
- * registered with serial core).  It's also used by sn_sal_module_init
+ * registered with serial core).  It's also used by sn_sal_init
  * right after we've registered with serial core.  The later only happens
  * if we didn't already come through here via sn_sal_serial_console_init.
  *
@@ -709,7 +709,7 @@ static void __init sn_sal_switch_to_asynch(struct sn_cons_port *port)
  * sn_sal_switch_to_interrupts - Switch to interrupt driven mode
  * @port: Our sn_cons_port (which contains the uart port)
  *
- * In sn_sal_module_init, after we're registered with serial core and
+ * In sn_sal_init, after we're registered with serial core and
  * the port is added, this function is called to switch us to interrupt
  * mode.  We were previously in asynch/polling mode (using init_timer).
  *
@@ -773,7 +773,7 @@ static struct uart_driver sal_console_uart = {
 };
 
 /**
- * sn_sal_module_init - When the kernel loads us, get us rolling w/ serial core
+ * sn_sal_init - When the kernel loads us, get us rolling w/ serial core
  *
  * Before this is called, we've been printing kernel messages in a special
  * early mode not making use of the serial core infrastructure.  When our
@@ -781,7 +781,7 @@ static struct uart_driver sal_console_uart = {
  * core and try to enable interrupt driven mode.
  *
  */
-static int __init sn_sal_module_init(void)
+static int __init sn_sal_init(void)
 {
 	int retval;
 
@@ -811,7 +811,7 @@ static int __init sn_sal_module_init(void)
 
 	if (uart_register_driver(&sal_console_uart) < 0) {
 		printk
-		    ("ERROR sn_sal_module_init failed uart_register_driver, line %d\n",
+		    ("ERROR sn_sal_init failed uart_register_driver, line %d\n",
 		     __LINE__);
 		return -ENODEV;
 	}
@@ -832,33 +832,19 @@ static int __init sn_sal_module_init(void)
 
 	/* when this driver is compiled in, the console initialization
 	 * will have already switched us into asynchronous operation
-	 * before we get here through the module initcalls */
+	 * before we get here through the initcalls */
 	if (!sal_console_port.sc_is_asynch) {
 		sn_sal_switch_to_asynch(&sal_console_port);
 	}
 
-	/* at this point (module_init) we can try to turn on interrupts */
+	/* at this point (device_init) we can try to turn on interrupts */
 	if (!IS_RUNNING_ON_SIMULATOR()) {
 		sn_sal_switch_to_interrupts(&sal_console_port);
 	}
 	sn_process_input = 1;
 	return 0;
 }
-
-/**
- * sn_sal_module_exit - When we're unloaded, remove the driver/port
- *
- */
-static void __exit sn_sal_module_exit(void)
-{
-	del_timer_sync(&sal_console_port.sc_timer);
-	uart_remove_one_port(&sal_console_uart, &sal_console_port.sc_port);
-	uart_unregister_driver(&sal_console_uart);
-	misc_deregister(&misc);
-}
-
-module_init(sn_sal_module_init);
-module_exit(sn_sal_module_exit);
+device_initcall(sn_sal_init);
 
 /**
  * puts_raw_fixed - sn_sal_console_write helper for adding \r's as required

drivers/tty/serial/stm32-usart.c

@@ -6,7 +6,7 @@
  * Inspired by st-asc.c from STMicroelectronics (c)
  */
 
-#if defined(CONFIG_SERIAL_STM32_USART_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
+#if defined(CONFIG_SERIAL_STM32_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
 #define SUPPORT_SYSRQ
 #endif
 

drivers/tty/serial/suncore.c

@@ -10,7 +10,6 @@
  * Copyright (C) 2002 David S. Miller (davem@redhat.com)
  */
 
-#include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/console.h>
 #include <linux/tty.h>
@@ -234,14 +233,10 @@ static int __init suncore_init(void)
 {
 	return 0;
 }
+device_initcall(suncore_init);
 
-static void __exit suncore_exit(void)
-{
-}
-
-module_init(suncore_init);
-module_exit(suncore_exit);
-
+#if 0 /* ..def MODULE ; never supported as such */
 MODULE_AUTHOR("Eddie C. Dost, David S. Miller");
 MODULE_DESCRIPTION("Sun serial common layer");
 MODULE_LICENSE("GPL");
+#endif

drivers/tty/serial/sunhv.c

@@ -3,7 +3,6 @@
  * Copyright (C) 2006, 2007 David S. Miller (davem@davemloft.net)
  */
 
-#include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/errno.h>
 #include <linux/tty.h>
@@ -621,7 +620,6 @@ static const struct of_device_id hv_match[] = {
 	},
 	{},
 };
-MODULE_DEVICE_TABLE(of, hv_match);
 
 static struct platform_driver hv_driver = {
 	.driver = {
@@ -639,16 +637,11 @@ static int __init sunhv_init(void)
 
 	return platform_driver_register(&hv_driver);
 }
+device_initcall(sunhv_init);
 
-static void __exit sunhv_exit(void)
-{
-	platform_driver_unregister(&hv_driver);
-}
-
-module_init(sunhv_init);
-module_exit(sunhv_exit);
-
+#if 0 /* ...def MODULE ; never supported as such */
 MODULE_AUTHOR("David S. Miller");
 MODULE_DESCRIPTION("SUN4V Hypervisor console driver");
 MODULE_VERSION("2.0");
 MODULE_LICENSE("GPL");
+#endif

drivers/tty/serial/ucc_uart.c

@@ -950,7 +950,7 @@ static void qe_uart_set_termios(struct uart_port *port,
 	if ((termios->c_cflag & CREAD) == 0)
 		port->read_status_mask &= ~BD_SC_EMPTY;
 
-	baud = uart_get_baud_rate(port, termios, old, 0, 115200);
+	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16);
 
 	/* Do we really need a spinlock here? */
 	spin_lock_irqsave(&port->lock, flags);

drivers/tty/tty_buffer.c

@@ -291,12 +291,11 @@ static int __tty_buffer_request_room(struct tty_port *port, size_t size,
 			n->flags = flags;
 			buf->tail = n;
 			b->commit = b->used;
-			/* paired w/ barrier in flush_to_ldisc(); ensures the
+			/* paired w/ acquire in flush_to_ldisc(); ensures the
 			 * latest commit value can be read before the head is
 			 * advanced to the next buffer
 			 */
-			smp_wmb();
-			b->next = n;
+			smp_store_release(&b->next, n);
 		} else if (change)
 			size = 0;
 		else
@@ -445,7 +444,6 @@ receive_buf(struct tty_struct *tty, struct tty_buffer *head, int count)
 		if (count)
 			disc->ops->receive_buf(tty, p, f, count);
 	}
-	head->read += count;
 	return count;
 }
 
@@ -488,12 +486,11 @@ static void flush_to_ldisc(struct work_struct *work)
 		if (atomic_read(&buf->priority))
 			break;
 
-		next = head->next;
-		/* paired w/ barrier in __tty_buffer_request_room();
+		/* paired w/ release in __tty_buffer_request_room();
 		 * ensures commit value read is not stale if the head
 		 * is advancing to the next buffer
 		 */
-		smp_rmb();
+		next = smp_load_acquire(&head->next);
 		count = head->commit - head->read;
 		if (!count) {
 			if (next == NULL) {
@@ -508,6 +505,7 @@ static void flush_to_ldisc(struct work_struct *work)
 		count = receive_buf(tty, head, count);
 		if (!count)
 			break;
+		head->read += count;
 	}
 
 	mutex_unlock(&buf->lock);

drivers/tty/tty_io.c

@@ -106,6 +106,11 @@
 #include <linux/nsproxy.h>
 
 #undef TTY_DEBUG_HANGUP
+#ifdef TTY_DEBUG_HANGUP
+# define tty_debug_hangup(tty, f, args...)	tty_debug(tty, f, ##args)
+#else
+# define tty_debug_hangup(tty, f, args...)	do { } while (0)
+#endif
 
 #define TTY_PARANOIA_CHECK 1
 #define CHECK_TTY_COUNT 1
@@ -388,33 +393,40 @@ EXPORT_SYMBOL_GPL(tty_find_polling_driver);
 int tty_check_change(struct tty_struct *tty)
 {
 	unsigned long flags;
+	struct pid *pgrp;
 	int ret = 0;
 
 	if (current->signal->tty != tty)
 		return 0;
 
+	rcu_read_lock();
+	pgrp = task_pgrp(current);
+
 	spin_lock_irqsave(&tty->ctrl_lock, flags);
 
 	if (!tty->pgrp) {
 		printk(KERN_WARNING "tty_check_change: tty->pgrp == NULL!\n");
 		goto out_unlock;
 	}
-	if (task_pgrp(current) == tty->pgrp)
+	if (pgrp == tty->pgrp)
 		goto out_unlock;
 	spin_unlock_irqrestore(&tty->ctrl_lock, flags);
+
 	if (is_ignored(SIGTTOU))
-		goto out;
+		goto out_rcuunlock;
 	if (is_current_pgrp_orphaned()) {
 		ret = -EIO;
-		goto out;
+		goto out_rcuunlock;
 	}
-	kill_pgrp(task_pgrp(current), SIGTTOU, 1);
+	kill_pgrp(pgrp, SIGTTOU, 1);
+	rcu_read_unlock();
 	set_thread_flag(TIF_SIGPENDING);
 	ret = -ERESTARTSYS;
-out:
 	return ret;
 out_unlock:
 	spin_unlock_irqrestore(&tty->ctrl_lock, flags);
+out_rcuunlock:
+	rcu_read_unlock();
 	return ret;
 }
 
@@ -524,7 +536,8 @@ static void __proc_set_tty(struct tty_struct *tty)
 	spin_unlock_irqrestore(&tty->ctrl_lock, flags);
 	tty->session = get_pid(task_session(current));
 	if (current->signal->tty) {
-		printk(KERN_DEBUG "tty not NULL!!\n");
+		tty_debug(tty, "current tty %s not NULL!!\n",
+			  current->signal->tty->name);
 		tty_kref_put(current->signal->tty);
 	}
 	put_pid(current->signal->tty_old_pgrp);
@@ -766,9 +779,7 @@ static void do_tty_hangup(struct work_struct *work)
 
 void tty_hangup(struct tty_struct *tty)
 {
-#ifdef TTY_DEBUG_HANGUP
-	printk(KERN_DEBUG "%s hangup...\n", tty_name(tty));
-#endif
+	tty_debug_hangup(tty, "\n");
 	schedule_work(&tty->hangup_work);
 }
 
@@ -785,9 +796,7 @@ EXPORT_SYMBOL(tty_hangup);
 
 void tty_vhangup(struct tty_struct *tty)
 {
-#ifdef TTY_DEBUG_HANGUP
-	printk(KERN_DEBUG "%s vhangup...\n", tty_name(tty));
-#endif
+	tty_debug_hangup(tty, "\n");
 	__tty_hangup(tty, 0);
 }
 
@@ -824,9 +833,7 @@ void tty_vhangup_self(void)
 
 static void tty_vhangup_session(struct tty_struct *tty)
 {
-#ifdef TTY_DEBUG_HANGUP
-	printk(KERN_DEBUG "%s vhangup session...\n", tty_name(tty));
-#endif
+	tty_debug_hangup(tty, "\n");
 	__tty_hangup(tty, 1);
 }
 
@@ -920,12 +927,8 @@ void disassociate_ctty(int on_exit)
 		tty->pgrp = NULL;
 		spin_unlock_irqrestore(&tty->ctrl_lock, flags);
 		tty_kref_put(tty);
-	} else {
-#ifdef TTY_DEBUG_HANGUP
-		printk(KERN_DEBUG "error attempted to write to tty [0x%p]"
-		       " = NULL", tty);
-#endif
-	}
+	} else
+		tty_debug_hangup(tty, "no current tty\n");
 
 	spin_unlock_irq(&current->sighand->siglock);
 	/* Now clear signal->tty under the lock */
@@ -1705,8 +1708,7 @@ static int tty_release_checks(struct tty_struct *tty, int idx)
 {
 #ifdef TTY_PARANOIA_CHECK
 	if (idx < 0 || idx >= tty->driver->num) {
-		printk(KERN_DEBUG "%s: bad idx when trying to free (%s)\n",
-				__func__, tty->name);
+		tty_debug(tty, "bad idx %d\n", idx);
 		return -1;
 	}
 
@@ -1715,20 +1717,20 @@ static int tty_release_checks(struct tty_struct *tty, int idx)
 		return 0;
 
 	if (tty != tty->driver->ttys[idx]) {
-		printk(KERN_DEBUG "%s: driver.table[%d] not tty for (%s)\n",
-				__func__, idx, tty->name);
+		tty_debug(tty, "bad driver table[%d] = %p\n",
+			  idx, tty->driver->ttys[idx]);
 		return -1;
 	}
 	if (tty->driver->other) {
 		struct tty_struct *o_tty = tty->link;
 
 		if (o_tty != tty->driver->other->ttys[idx]) {
-			printk(KERN_DEBUG "%s: other->table[%d] not o_tty for (%s)\n",
-					__func__, idx, tty->name);
+			tty_debug(tty, "bad other table[%d] = %p\n",
+				  idx, tty->driver->other->ttys[idx]);
 			return -1;
 		}
 		if (o_tty->link != tty) {
-			printk(KERN_DEBUG "%s: bad pty pointers\n", __func__);
+			tty_debug(tty, "bad link = %p\n", o_tty->link);
 			return -1;
 		}
 	}
@@ -1782,10 +1784,7 @@ int tty_release(struct inode *inode, struct file *filp)
 		return 0;
 	}
 
-#ifdef TTY_DEBUG_HANGUP
-	printk(KERN_DEBUG "%s: %s (tty count=%d)...\n", __func__,
-			tty_name(tty), tty->count);
-#endif
+	tty_debug_hangup(tty, "(tty count=%d)...\n", tty->count);
 
 	if (tty->ops->close)
 		tty->ops->close(tty, filp);
@@ -1895,9 +1894,7 @@ int tty_release(struct inode *inode, struct file *filp)
 	if (!final)
 		return 0;
 
-#ifdef TTY_DEBUG_HANGUP
-	printk(KERN_DEBUG "%s: %s: final close\n", __func__, tty_name(tty));
-#endif
+	tty_debug_hangup(tty, "final close\n");
 	/*
 	 * Ask the line discipline code to release its structures
 	 */
@@ -1906,10 +1903,7 @@ int tty_release(struct inode *inode, struct file *filp)
 	/* Wait for pending work before tty destruction commmences */
 	tty_flush_works(tty);
 
-#ifdef TTY_DEBUG_HANGUP
-	printk(KERN_DEBUG "%s: %s: freeing structure...\n", __func__,
-	       tty_name(tty));
-#endif
+	tty_debug_hangup(tty, "freeing structure...\n");
 	/*
 	 * The release_tty function takes care of the details of clearing
 	 * the slots and preserving the termios structure. The tty_unlock_pair
@@ -2098,9 +2092,9 @@ retry_open:
 	if (tty->driver->type == TTY_DRIVER_TYPE_PTY &&
 	    tty->driver->subtype == PTY_TYPE_MASTER)
 		noctty = 1;
-#ifdef TTY_DEBUG_HANGUP
-	printk(KERN_DEBUG "%s: opening %s...\n", __func__, tty->name);
-#endif
+
+	tty_debug_hangup(tty, "(tty count=%d)\n", tty->count);
+
 	if (tty->ops->open)
 		retval = tty->ops->open(tty, filp);
 	else
@@ -2108,10 +2102,8 @@ retry_open:
 	filp->f_flags = saved_flags;
 
 	if (retval) {
-#ifdef TTY_DEBUG_HANGUP
-		printk(KERN_DEBUG "%s: error %d in opening %s...\n", __func__,
-				retval, tty->name);
-#endif
+		tty_debug_hangup(tty, "error %d, releasing...\n", retval);
+
 		tty_unlock(tty); /* need to call tty_release without BTM */
 		tty_release(inode, filp);
 		if (retval != -ERESTARTSYS)
@@ -3160,9 +3152,12 @@ static int tty_cdev_add(struct tty_driver *driver, dev_t dev,
 		unsigned int index, unsigned int count)
 {
 	/* init here, since reused cdevs cause crashes */
-	cdev_init(&driver->cdevs[index], &tty_fops);
-	driver->cdevs[index].owner = driver->owner;
-	return cdev_add(&driver->cdevs[index], dev, count);
+	driver->cdevs[index] = cdev_alloc();
+	if (!driver->cdevs[index])
+		return -ENOMEM;
+	cdev_init(driver->cdevs[index], &tty_fops);
+	driver->cdevs[index]->owner = driver->owner;
+	return cdev_add(driver->cdevs[index], dev, count);
 }
 
 /**
@@ -3268,8 +3263,10 @@ struct device *tty_register_device_attr(struct tty_driver *driver,
 
 error:
 	put_device(dev);
-	if (cdev)
-		cdev_del(&driver->cdevs[index]);
+	if (cdev) {
+		cdev_del(driver->cdevs[index]);
+		driver->cdevs[index] = NULL;
+	}
 	return ERR_PTR(retval);
 }
 EXPORT_SYMBOL_GPL(tty_register_device_attr);
@@ -3289,8 +3286,10 @@ void tty_unregister_device(struct tty_driver *driver, unsigned index)
 {
 	device_destroy(tty_class,
 		MKDEV(driver->major, driver->minor_start) + index);
-	if (!(driver->flags & TTY_DRIVER_DYNAMIC_ALLOC))
-		cdev_del(&driver->cdevs[index]);
+	if (!(driver->flags & TTY_DRIVER_DYNAMIC_ALLOC)) {
+		cdev_del(driver->cdevs[index]);
+		driver->cdevs[index] = NULL;
+	}
 }
 EXPORT_SYMBOL(tty_unregister_device);
 
@@ -3355,6 +3354,7 @@ err_free_all:
 	kfree(driver->ports);
 	kfree(driver->ttys);
 	kfree(driver->termios);
+	kfree(driver->cdevs);
 	kfree(driver);
 	return ERR_PTR(err);
 }
@@ -3383,7 +3383,7 @@ static void destruct_tty_driver(struct kref *kref)
 		}
 		proc_tty_unregister_driver(driver);
 		if (driver->flags & TTY_DRIVER_DYNAMIC_ALLOC)
-			cdev_del(&driver->cdevs[0]);
+			cdev_del(driver->cdevs[0]);
 	}
 	kfree(driver->cdevs);
 	kfree(driver->ports);

drivers/tty/tty_ioctl.c

@@ -26,6 +26,12 @@
 
 #undef TTY_DEBUG_WAIT_UNTIL_SENT
 
+#ifdef TTY_DEBUG_WAIT_UNTIL_SENT
+# define tty_debug_wait_until_sent(tty, f, args...)    tty_debug(tty, f, ##args)
+#else
+# define tty_debug_wait_until_sent(tty, f, args...)    do {} while (0)
+#endif
+
 #undef	DEBUG
 
 /*
@@ -210,9 +216,8 @@ int tty_unthrottle_safe(struct tty_struct *tty)
 
 void tty_wait_until_sent(struct tty_struct *tty, long timeout)
 {
-#ifdef TTY_DEBUG_WAIT_UNTIL_SENT
-	printk(KERN_DEBUG "%s wait until sent...\n", tty_name(tty));
-#endif
+	tty_debug_wait_until_sent(tty, "\n");
+
 	if (!timeout)
 		timeout = MAX_SCHEDULE_TIMEOUT;
 

drivers/tty/tty_ldisc.c

@@ -22,9 +22,7 @@
 #undef LDISC_DEBUG_HANGUP
 
 #ifdef LDISC_DEBUG_HANGUP
-#define tty_ldisc_debug(tty, f, args...) ({				  \
-	printk(KERN_DEBUG "%s: %s: " f, __func__, tty_name(tty), ##args); \
-})
+#define tty_ldisc_debug(tty, f, args...)	tty_debug(tty, f, ##args)
 #else
 #define tty_ldisc_debug(tty, f, args...)
 #endif
@@ -449,6 +447,8 @@ static int tty_ldisc_open(struct tty_struct *tty, struct tty_ldisc *ld)
 		ret = ld->ops->open(tty);
 		if (ret)
 			clear_bit(TTY_LDISC_OPEN, &tty->flags);
+
+		tty_ldisc_debug(tty, "%p: opened\n", tty->ldisc);
 		return ret;
 	}
 	return 0;
@@ -469,6 +469,7 @@ static void tty_ldisc_close(struct tty_struct *tty, struct tty_ldisc *ld)
 	clear_bit(TTY_LDISC_OPEN, &tty->flags);
 	if (ld->ops->close)
 		ld->ops->close(tty);
+	tty_ldisc_debug(tty, "%p: closed\n", tty->ldisc);
 }
 
 /**
@@ -662,7 +663,7 @@ void tty_ldisc_hangup(struct tty_struct *tty)
 	int reset = tty->driver->flags & TTY_DRIVER_RESET_TERMIOS;
 	int err = 0;
 
-	tty_ldisc_debug(tty, "closing ldisc: %p\n", tty->ldisc);
+	tty_ldisc_debug(tty, "%p: closing\n", tty->ldisc);
 
 	ld = tty_ldisc_ref(tty);
 	if (ld != NULL) {
@@ -712,7 +713,7 @@ void tty_ldisc_hangup(struct tty_struct *tty)
 	if (reset)
 		tty_reset_termios(tty);
 
-	tty_ldisc_debug(tty, "re-opened ldisc: %p\n", tty->ldisc);
+	tty_ldisc_debug(tty, "%p: re-opened\n", tty->ldisc);
 }
 
 /**
@@ -776,8 +777,6 @@ void tty_ldisc_release(struct tty_struct *tty)
 	 * it does not race with the set_ldisc code path.
 	 */
 
-	tty_ldisc_debug(tty, "closing ldisc: %p\n", tty->ldisc);
-
 	tty_ldisc_lock_pair(tty, o_tty);
 	tty_ldisc_kill(tty);
 	if (o_tty)
@@ -787,7 +786,7 @@ void tty_ldisc_release(struct tty_struct *tty)
 	/* And the memory resources remaining (buffers, termios) will be
 	   disposed of when the kref hits zero */
 
-	tty_ldisc_debug(tty, "ldisc closed\n");
+	tty_ldisc_debug(tty, "released\n");
 }
 
 /**

include/linux/amba/serial.h

@@ -33,12 +33,14 @@
 #define UART01x_DR		0x00	/* Data read or written from the interface. */
 #define UART01x_RSR		0x04	/* Receive status register (Read). */
 #define UART01x_ECR		0x04	/* Error clear register (Write). */
+#define ZX_UART01x_DR		0x04	/* Data read or written from the interface. */
 #define UART010_LCRH		0x08	/* Line control register, high byte. */
 #define ST_UART011_DMAWM	0x08    /* DMA watermark configure register. */
 #define UART010_LCRM		0x0C	/* Line control register, middle byte. */
 #define ST_UART011_TIMEOUT	0x0C    /* Timeout period register. */
 #define UART010_LCRL		0x10	/* Line control register, low byte. */
 #define UART010_CR		0x14	/* Control register. */
+#define ZX_UART01x_FR		0x14	/* Flag register (Read only). */
 #define UART01x_FR		0x18	/* Flag register (Read only). */
 #define UART010_IIR		0x1C	/* Interrupt identification register (Read). */
 #define UART010_ICR		0x1C	/* Interrupt clear register (Write). */
@@ -49,13 +51,21 @@
 #define UART011_LCRH		0x2c	/* Line control register. */
 #define ST_UART011_LCRH_TX	0x2c    /* Tx Line control register. */
 #define UART011_CR		0x30	/* Control register. */
+#define ZX_UART011_LCRH_TX	0x30    /* Tx Line control register. */
 #define UART011_IFLS		0x34	/* Interrupt fifo level select. */
+#define ZX_UART011_CR		0x34	/* Control register. */
+#define ZX_UART011_IFLS		0x38	/* Interrupt fifo level select. */
 #define UART011_IMSC		0x38	/* Interrupt mask. */
 #define UART011_RIS		0x3c	/* Raw interrupt status. */
 #define UART011_MIS		0x40	/* Masked interrupt status. */
+#define ZX_UART011_IMSC		0x40	/* Interrupt mask. */
 #define UART011_ICR		0x44	/* Interrupt clear register. */
+#define ZX_UART011_RIS		0x44	/* Raw interrupt status. */
 #define UART011_DMACR		0x48	/* DMA control register. */
+#define ZX_UART011_MIS		0x48	/* Masked interrupt status. */
+#define ZX_UART011_ICR		0x4c	/* Interrupt clear register. */
 #define ST_UART011_XFCR		0x50	/* XON/XOFF control register. */
+#define ZX_UART011_DMACR	0x50	/* DMA control register. */
 #define ST_UART011_XON1		0x54	/* XON1 register. */
 #define ST_UART011_XON2		0x58	/* XON2 register. */
 #define ST_UART011_XOFF1	0x5C	/* XON1 register. */
@@ -75,15 +85,19 @@
 #define UART01x_RSR_PE 		0x02
 #define UART01x_RSR_FE 		0x01
 
+#define ZX_UART01x_FR_BUSY	0x300
 #define UART011_FR_RI		0x100
 #define UART011_FR_TXFE		0x080
 #define UART011_FR_RXFF		0x040
 #define UART01x_FR_TXFF		0x020
 #define UART01x_FR_RXFE		0x010
 #define UART01x_FR_BUSY		0x008
+#define ZX_UART01x_FR_DSR       0x008
 #define UART01x_FR_DCD 		0x004
 #define UART01x_FR_DSR 		0x002
+#define ZX_UART01x_FR_CTS	0x002
 #define UART01x_FR_CTS 		0x001
+#define ZX_UART011_FR_RI	0x001
 #define UART01x_FR_TMSK		(UART01x_FR_TXFF + UART01x_FR_BUSY)
 
 #define UART011_CR_CTSEN	0x8000	/* CTS hardware flow control */

include/linux/atmel_serial.h

@@ -16,115 +16,151 @@
 #ifndef ATMEL_SERIAL_H
 #define ATMEL_SERIAL_H
 
-#define ATMEL_US_CR		0x00			/* Control Register */
-#define		ATMEL_US_RSTRX		(1 <<  2)		/* Reset Receiver */
-#define		ATMEL_US_RSTTX		(1 <<  3)		/* Reset Transmitter */
-#define		ATMEL_US_RXEN		(1 <<  4)		/* Receiver Enable */
-#define		ATMEL_US_RXDIS		(1 <<  5)		/* Receiver Disable */
-#define		ATMEL_US_TXEN		(1 <<  6)		/* Transmitter Enable */
-#define		ATMEL_US_TXDIS		(1 <<  7)		/* Transmitter Disable */
-#define		ATMEL_US_RSTSTA		(1 <<  8)		/* Reset Status Bits */
-#define		ATMEL_US_STTBRK		(1 <<  9)		/* Start Break */
-#define		ATMEL_US_STPBRK		(1 << 10)		/* Stop Break */
-#define		ATMEL_US_STTTO		(1 << 11)		/* Start Time-out */
-#define		ATMEL_US_SENDA		(1 << 12)		/* Send Address */
-#define		ATMEL_US_RSTIT		(1 << 13)		/* Reset Iterations */
-#define		ATMEL_US_RSTNACK	(1 << 14)		/* Reset Non Acknowledge */
-#define		ATMEL_US_RETTO		(1 << 15)		/* Rearm Time-out */
-#define		ATMEL_US_DTREN		(1 << 16)		/* Data Terminal Ready Enable [AT91RM9200 only] */
-#define		ATMEL_US_DTRDIS		(1 << 17)		/* Data Terminal Ready Disable [AT91RM9200 only] */
-#define		ATMEL_US_RTSEN		(1 << 18)		/* Request To Send Enable */
-#define		ATMEL_US_RTSDIS		(1 << 19)		/* Request To Send Disable */
+#define ATMEL_US_CR		0x00	/* Control Register */
+#define	ATMEL_US_RSTRX		BIT(2)	/* Reset Receiver */
+#define	ATMEL_US_RSTTX		BIT(3)	/* Reset Transmitter */
+#define	ATMEL_US_RXEN		BIT(4)	/* Receiver Enable */
+#define	ATMEL_US_RXDIS		BIT(5)	/* Receiver Disable */
+#define	ATMEL_US_TXEN		BIT(6)	/* Transmitter Enable */
+#define	ATMEL_US_TXDIS		BIT(7)	/* Transmitter Disable */
+#define	ATMEL_US_RSTSTA		BIT(8)	/* Reset Status Bits */
+#define	ATMEL_US_STTBRK		BIT(9)	/* Start Break */
+#define	ATMEL_US_STPBRK		BIT(10)	/* Stop Break */
+#define	ATMEL_US_STTTO		BIT(11)	/* Start Time-out */
+#define	ATMEL_US_SENDA		BIT(12)	/* Send Address */
+#define	ATMEL_US_RSTIT		BIT(13)	/* Reset Iterations */
+#define	ATMEL_US_RSTNACK	BIT(14)	/* Reset Non Acknowledge */
+#define	ATMEL_US_RETTO		BIT(15)	/* Rearm Time-out */
+#define	ATMEL_US_DTREN		BIT(16)	/* Data Terminal Ready Enable */
+#define	ATMEL_US_DTRDIS		BIT(17)	/* Data Terminal Ready Disable */
+#define	ATMEL_US_RTSEN		BIT(18)	/* Request To Send Enable */
+#define	ATMEL_US_RTSDIS		BIT(19)	/* Request To Send Disable */
+#define	ATMEL_US_TXFCLR		BIT(24)	/* Transmit FIFO Clear */
+#define	ATMEL_US_RXFCLR		BIT(25)	/* Receive FIFO Clear */
+#define	ATMEL_US_TXFLCLR	BIT(26)	/* Transmit FIFO Lock Clear */
+#define	ATMEL_US_FIFOEN		BIT(30)	/* FIFO enable */
+#define	ATMEL_US_FIFODIS	BIT(31)	/* FIFO disable */
 
-#define ATMEL_US_MR		0x04			/* Mode Register */
-#define		ATMEL_US_USMODE		(0xf <<  0)		/* Mode of the USART */
-#define			ATMEL_US_USMODE_NORMAL		0
-#define			ATMEL_US_USMODE_RS485		1
-#define			ATMEL_US_USMODE_HWHS		2
-#define			ATMEL_US_USMODE_MODEM		3
-#define			ATMEL_US_USMODE_ISO7816_T0	4
-#define			ATMEL_US_USMODE_ISO7816_T1	6
-#define			ATMEL_US_USMODE_IRDA		8
-#define		ATMEL_US_USCLKS		(3   <<  4)		/* Clock Selection */
-#define			ATMEL_US_USCLKS_MCK		(0 <<  4)
-#define			ATMEL_US_USCLKS_MCK_DIV8	(1 <<  4)
-#define			ATMEL_US_USCLKS_SCK		(3 <<  4)
-#define		ATMEL_US_CHRL		(3   <<  6)		/* Character Length */
-#define			ATMEL_US_CHRL_5			(0 <<  6)
-#define			ATMEL_US_CHRL_6			(1 <<  6)
-#define			ATMEL_US_CHRL_7			(2 <<  6)
-#define			ATMEL_US_CHRL_8			(3 <<  6)
-#define		ATMEL_US_SYNC		(1 <<  8)		/* Synchronous Mode Select */
-#define		ATMEL_US_PAR		(7 <<  9)		/* Parity Type */
-#define			ATMEL_US_PAR_EVEN		(0 <<  9)
-#define			ATMEL_US_PAR_ODD		(1 <<  9)
-#define			ATMEL_US_PAR_SPACE		(2 <<  9)
-#define			ATMEL_US_PAR_MARK		(3 <<  9)
-#define			ATMEL_US_PAR_NONE		(4 <<  9)
-#define			ATMEL_US_PAR_MULTI_DROP		(6 <<  9)
-#define		ATMEL_US_NBSTOP		(3 << 12)		/* Number of Stop Bits */
-#define			ATMEL_US_NBSTOP_1		(0 << 12)
-#define			ATMEL_US_NBSTOP_1_5		(1 << 12)
-#define			ATMEL_US_NBSTOP_2		(2 << 12)
-#define		ATMEL_US_CHMODE		(3 << 14)		/* Channel Mode */
-#define			ATMEL_US_CHMODE_NORMAL		(0 << 14)
-#define			ATMEL_US_CHMODE_ECHO		(1 << 14)
-#define			ATMEL_US_CHMODE_LOC_LOOP	(2 << 14)
-#define			ATMEL_US_CHMODE_REM_LOOP	(3 << 14)
-#define		ATMEL_US_MSBF		(1 << 16)		/* Bit Order */
-#define		ATMEL_US_MODE9		(1 << 17)		/* 9-bit Character Length */
-#define		ATMEL_US_CLKO		(1 << 18)		/* Clock Output Select */
-#define		ATMEL_US_OVER		(1 << 19)		/* Oversampling Mode */
-#define		ATMEL_US_INACK		(1 << 20)		/* Inhibit Non Acknowledge */
-#define		ATMEL_US_DSNACK		(1 << 21)		/* Disable Successive NACK */
-#define		ATMEL_US_MAX_ITER	(7 << 24)		/* Max Iterations */
-#define		ATMEL_US_FILTER		(1 << 28)		/* Infrared Receive Line Filter */
+#define ATMEL_US_MR		0x04	/* Mode Register */
+#define	ATMEL_US_USMODE		GENMASK(3, 0)	/* Mode of the USART */
+#define		ATMEL_US_USMODE_NORMAL		0
+#define		ATMEL_US_USMODE_RS485		1
+#define		ATMEL_US_USMODE_HWHS		2
+#define		ATMEL_US_USMODE_MODEM		3
+#define		ATMEL_US_USMODE_ISO7816_T0	4
+#define		ATMEL_US_USMODE_ISO7816_T1	6
+#define		ATMEL_US_USMODE_IRDA		8
+#define	ATMEL_US_USCLKS		GENMASK(5, 4)	/* Clock Selection */
+#define		ATMEL_US_USCLKS_MCK		(0 <<  4)
+#define		ATMEL_US_USCLKS_MCK_DIV8	(1 <<  4)
+#define		ATMEL_US_USCLKS_SCK		(3 <<  4)
+#define	ATMEL_US_CHRL		GENMASK(7, 6)	/* Character Length */
+#define		ATMEL_US_CHRL_5			(0 <<  6)
+#define		ATMEL_US_CHRL_6			(1 <<  6)
+#define		ATMEL_US_CHRL_7			(2 <<  6)
+#define		ATMEL_US_CHRL_8			(3 <<  6)
+#define	ATMEL_US_SYNC		BIT(8)		/* Synchronous Mode Select */
+#define	ATMEL_US_PAR		GENMASK(11, 9)	/* Parity Type */
+#define		ATMEL_US_PAR_EVEN		(0 <<  9)
+#define		ATMEL_US_PAR_ODD		(1 <<  9)
+#define		ATMEL_US_PAR_SPACE		(2 <<  9)
+#define		ATMEL_US_PAR_MARK		(3 <<  9)
+#define		ATMEL_US_PAR_NONE		(4 <<  9)
+#define		ATMEL_US_PAR_MULTI_DROP		(6 <<  9)
+#define	ATMEL_US_NBSTOP		GENMASK(13, 12)	/* Number of Stop Bits */
+#define		ATMEL_US_NBSTOP_1		(0 << 12)
+#define		ATMEL_US_NBSTOP_1_5		(1 << 12)
+#define		ATMEL_US_NBSTOP_2		(2 << 12)
+#define	ATMEL_US_CHMODE		GENMASK(15, 14)	/* Channel Mode */
+#define		ATMEL_US_CHMODE_NORMAL		(0 << 14)
+#define		ATMEL_US_CHMODE_ECHO		(1 << 14)
+#define		ATMEL_US_CHMODE_LOC_LOOP	(2 << 14)
+#define		ATMEL_US_CHMODE_REM_LOOP	(3 << 14)
+#define	ATMEL_US_MSBF		BIT(16)	/* Bit Order */
+#define	ATMEL_US_MODE9		BIT(17)	/* 9-bit Character Length */
+#define	ATMEL_US_CLKO		BIT(18)	/* Clock Output Select */
+#define	ATMEL_US_OVER		BIT(19)	/* Oversampling Mode */
+#define	ATMEL_US_INACK		BIT(20)	/* Inhibit Non Acknowledge */
+#define	ATMEL_US_DSNACK		BIT(21)	/* Disable Successive NACK */
+#define	ATMEL_US_MAX_ITER	GENMASK(26, 24)	/* Max Iterations */
+#define	ATMEL_US_FILTER		BIT(28)	/* Infrared Receive Line Filter */
 
-#define ATMEL_US_IER		0x08			/* Interrupt Enable Register */
-#define		ATMEL_US_RXRDY		(1 <<  0)		/* Receiver Ready */
-#define		ATMEL_US_TXRDY		(1 <<  1)		/* Transmitter Ready */
-#define		ATMEL_US_RXBRK		(1 <<  2)		/* Break Received / End of Break */
-#define		ATMEL_US_ENDRX		(1 <<  3)		/* End of Receiver Transfer */
-#define		ATMEL_US_ENDTX		(1 <<  4)		/* End of Transmitter Transfer */
-#define		ATMEL_US_OVRE		(1 <<  5)		/* Overrun Error */
-#define		ATMEL_US_FRAME		(1 <<  6)		/* Framing Error */
-#define		ATMEL_US_PARE		(1 <<  7)		/* Parity Error */
-#define		ATMEL_US_TIMEOUT	(1 <<  8)		/* Receiver Time-out */
-#define		ATMEL_US_TXEMPTY	(1 <<  9)		/* Transmitter Empty */
-#define		ATMEL_US_ITERATION	(1 << 10)		/* Max number of Repetitions Reached */
-#define		ATMEL_US_TXBUFE		(1 << 11)		/* Transmission Buffer Empty */
-#define		ATMEL_US_RXBUFF		(1 << 12)		/* Reception Buffer Full */
-#define		ATMEL_US_NACK		(1 << 13)		/* Non Acknowledge */
-#define		ATMEL_US_RIIC		(1 << 16)		/* Ring Indicator Input Change [AT91RM9200 only] */
-#define		ATMEL_US_DSRIC		(1 << 17)		/* Data Set Ready Input Change [AT91RM9200 only] */
-#define		ATMEL_US_DCDIC		(1 << 18)		/* Data Carrier Detect Input Change [AT91RM9200 only] */
-#define		ATMEL_US_CTSIC		(1 << 19)		/* Clear to Send Input Change */
-#define		ATMEL_US_RI		(1 << 20)		/* RI */
-#define		ATMEL_US_DSR		(1 << 21)		/* DSR */
-#define		ATMEL_US_DCD		(1 << 22)		/* DCD */
-#define		ATMEL_US_CTS		(1 << 23)		/* CTS */
+#define ATMEL_US_IER		0x08	/* Interrupt Enable Register */
+#define	ATMEL_US_RXRDY		BIT(0)	/* Receiver Ready */
+#define	ATMEL_US_TXRDY		BIT(1)	/* Transmitter Ready */
+#define	ATMEL_US_RXBRK		BIT(2)	/* Break Received / End of Break */
+#define	ATMEL_US_ENDRX		BIT(3)	/* End of Receiver Transfer */
+#define	ATMEL_US_ENDTX		BIT(4)	/* End of Transmitter Transfer */
+#define	ATMEL_US_OVRE		BIT(5)	/* Overrun Error */
+#define	ATMEL_US_FRAME		BIT(6)	/* Framing Error */
+#define	ATMEL_US_PARE		BIT(7)	/* Parity Error */
+#define	ATMEL_US_TIMEOUT	BIT(8)	/* Receiver Time-out */
+#define	ATMEL_US_TXEMPTY	BIT(9)	/* Transmitter Empty */
+#define	ATMEL_US_ITERATION	BIT(10)	/* Max number of Repetitions Reached */
+#define	ATMEL_US_TXBUFE		BIT(11)	/* Transmission Buffer Empty */
+#define	ATMEL_US_RXBUFF		BIT(12)	/* Reception Buffer Full */
+#define	ATMEL_US_NACK		BIT(13)	/* Non Acknowledge */
+#define	ATMEL_US_RIIC		BIT(16)	/* Ring Indicator Input Change */
+#define	ATMEL_US_DSRIC		BIT(17)	/* Data Set Ready Input Change */
+#define	ATMEL_US_DCDIC		BIT(18)	/* Data Carrier Detect Input Change */
+#define	ATMEL_US_CTSIC		BIT(19)	/* Clear to Send Input Change */
+#define	ATMEL_US_RI		BIT(20)	/* RI */
+#define	ATMEL_US_DSR		BIT(21)	/* DSR */
+#define	ATMEL_US_DCD		BIT(22)	/* DCD */
+#define	ATMEL_US_CTS		BIT(23)	/* CTS */
 
-#define ATMEL_US_IDR		0x0c			/* Interrupt Disable Register */
-#define ATMEL_US_IMR		0x10			/* Interrupt Mask Register */
-#define ATMEL_US_CSR		0x14			/* Channel Status Register */
-#define ATMEL_US_RHR		0x18			/* Receiver Holding Register */
-#define ATMEL_US_THR		0x1c			/* Transmitter Holding Register */
-#define		ATMEL_US_SYNH		(1 << 15)		/* Transmit/Receive Sync [AT91SAM9261 only] */
+#define ATMEL_US_IDR		0x0c	/* Interrupt Disable Register */
+#define ATMEL_US_IMR		0x10	/* Interrupt Mask Register */
+#define ATMEL_US_CSR		0x14	/* Channel Status Register */
+#define ATMEL_US_RHR		0x18	/* Receiver Holding Register */
+#define ATMEL_US_THR		0x1c	/* Transmitter Holding Register */
+#define	ATMEL_US_SYNH		BIT(15)	/* Transmit/Receive Sync */
 
-#define ATMEL_US_BRGR		0x20			/* Baud Rate Generator Register */
-#define		ATMEL_US_CD		(0xffff << 0)		/* Clock Divider */
+#define ATMEL_US_BRGR		0x20	/* Baud Rate Generator Register */
+#define	ATMEL_US_CD		GENMASK(15, 0)	/* Clock Divider */
 
-#define ATMEL_US_RTOR		0x24			/* Receiver Time-out Register */
-#define		ATMEL_US_TO		(0xffff << 0)		/* Time-out Value */
+#define ATMEL_US_RTOR		0x24	/* Receiver Time-out Register */
+#define	ATMEL_US_TO		GENMASK(15, 0)	/* Time-out Value */
 
-#define ATMEL_US_TTGR		0x28			/* Transmitter Timeguard Register */
-#define		ATMEL_US_TG		(0xff << 0)		/* Timeguard Value */
+#define ATMEL_US_TTGR		0x28	/* Transmitter Timeguard Register */
+#define	ATMEL_US_TG		GENMASK(7, 0)	/* Timeguard Value */
 
-#define ATMEL_US_FIDI		0x40			/* FI DI Ratio Register */
-#define ATMEL_US_NER		0x44			/* Number of Errors Register */
-#define ATMEL_US_IF		0x4c			/* IrDA Filter Register */
+#define ATMEL_US_FIDI		0x40	/* FI DI Ratio Register */
+#define ATMEL_US_NER		0x44	/* Number of Errors Register */
+#define ATMEL_US_IF		0x4c	/* IrDA Filter Register */
 
-#define ATMEL_US_NAME		0xf0			/* Ip Name */
-#define ATMEL_US_VERSION	0xfc			/* Ip Version */
+#define ATMEL_US_CMPR		0x90	/* Comparaison Register */
+#define ATMEL_US_FMR		0xa0	/* FIFO Mode Register */
+#define	ATMEL_US_TXRDYM(data)	(((data) & 0x3) << 0)	/* TX Ready Mode */
+#define	ATMEL_US_RXRDYM(data)	(((data) & 0x3) << 4)	/* RX Ready Mode */
+#define		ATMEL_US_ONE_DATA	0x0
+#define		ATMEL_US_TWO_DATA	0x1
+#define		ATMEL_US_FOUR_DATA	0x2
+#define	ATMEL_US_FRTSC		BIT(7)	/* FIFO RTS pin Control */
+#define	ATMEL_US_TXFTHRES(thr)	(((thr) & 0x3f) << 8)	/* TX FIFO Threshold */
+#define	ATMEL_US_RXFTHRES(thr)	(((thr) & 0x3f) << 16)	/* RX FIFO Threshold */
+#define	ATMEL_US_RXFTHRES2(thr)	(((thr) & 0x3f) << 24)	/* RX FIFO Threshold2 */
+
+#define ATMEL_US_FLR		0xa4	/* FIFO Level Register */
+#define	ATMEL_US_TXFL(reg)	(((reg) >> 0) & 0x3f)	/* TX FIFO Level */
+#define	ATMEL_US_RXFL(reg)	(((reg) >> 16) & 0x3f)	/* RX FIFO Level */
+
+#define ATMEL_US_FIER		0xa8	/* FIFO Interrupt Enable Register */
+#define ATMEL_US_FIDR		0xac	/* FIFO Interrupt Disable Register */
+#define ATMEL_US_FIMR		0xb0	/* FIFO Interrupt Mask Register */
+#define ATMEL_US_FESR		0xb4	/* FIFO Event Status Register */
+#define	ATMEL_US_TXFEF		BIT(0)	/* Transmit FIFO Empty Flag */
+#define	ATMEL_US_TXFFF		BIT(1)	/* Transmit FIFO Full Flag */
+#define	ATMEL_US_TXFTHF		BIT(2)	/* Transmit FIFO Threshold Flag */
+#define	ATMEL_US_RXFEF		BIT(3)	/* Receive FIFO Empty Flag */
+#define	ATMEL_US_RXFFF		BIT(4)	/* Receive FIFO Full Flag */
+#define	ATMEL_US_RXFTHF		BIT(5)	/* Receive FIFO Threshold Flag */
+#define	ATMEL_US_TXFPTEF	BIT(6)	/* Transmit FIFO Pointer Error Flag */
+#define	ATMEL_US_RXFPTEF	BIT(7)	/* Receive FIFO Pointer Error Flag */
+#define	ATMEL_US_TXFLOCK	BIT(8)	/* Transmit FIFO Lock (FESR only) */
+#define	ATMEL_US_RXFTHF2	BIT(9)	/* Receive FIFO Threshold Flag 2 */
+
+#define ATMEL_US_NAME		0xf0	/* Ip Name */
+#define ATMEL_US_VERSION	0xfc	/* Ip Version */
 
 #endif

include/linux/serial_8250.h

@@ -136,8 +136,6 @@ void serial8250_resume_port(int line);
 
 extern int early_serial_setup(struct uart_port *port);
 
-extern unsigned int serial8250_early_in(struct uart_port *port, int offset);
-extern void serial8250_early_out(struct uart_port *port, int offset, int value);
 extern int early_serial8250_setup(struct earlycon_device *device,
 					 const char *options);
 extern void serial8250_do_set_termios(struct uart_port *port,
@@ -152,6 +150,11 @@ int serial8250_handle_irq(struct uart_port *port, unsigned int iir);
 unsigned char serial8250_rx_chars(struct uart_8250_port *up, unsigned char lsr);
 void serial8250_tx_chars(struct uart_8250_port *up);
 unsigned int serial8250_modem_status(struct uart_8250_port *up);
+void serial8250_init_port(struct uart_8250_port *up);
+void serial8250_set_defaults(struct uart_8250_port *up);
+void serial8250_console_write(struct uart_8250_port *up, const char *s,
+			      unsigned int count);
+int serial8250_console_setup(struct uart_port *port, char *options, bool probe);
 
 extern void serial8250_set_isa_configurator(void (*v)
 					(int port, struct uart_port *up,

include/linux/tty.h

@@ -709,4 +709,10 @@ static inline void proc_tty_register_driver(struct tty_driver *d) {}
 static inline void proc_tty_unregister_driver(struct tty_driver *d) {}
 #endif
 
+#define tty_debug(tty, f, args...)					\
+	do {								\
+		printk(KERN_DEBUG "%s: %s: " f, __func__,		\
+		       tty_name(tty), ##args);				\
+	} while (0)
+
 #endif

include/linux/tty_driver.h

@@ -296,7 +296,7 @@ struct tty_operations {
 struct tty_driver {
 	int	magic;		/* magic number for this structure */
 	struct kref kref;	/* Reference management */
-	struct cdev *cdevs;
+	struct cdev **cdevs;
 	struct module	*owner;
 	const char	*driver_name;
 	const char	*name;

include/uapi/linux/gsmmux.h

@@ -3,6 +3,7 @@
 
 #include <linux/if.h>
 #include <linux/ioctl.h>
+#include <linux/types.h>
 
 struct gsm_config
 {