Merge branch 'i2c/for-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

Pull i2c updates from Wolfram Sang:

 - New drivers: UniPhier (with and without FIFO)

 - some drivers got some bigger rework: ismt, designware, img-scb (rcar
   had to be reverted because issues were showing up just lately)

 - ACPI: reworked the device scanning and added support for muxes

... and quite a lot of driver bugfixes and cleanups this time.  All
files touched outside of the i2c realm have proper acks.

* 'i2c/for-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (70 commits)
  i2c: rcar: Revert the latest refactoring series
  i2c: pnx: remove superfluous assignment
  MAINTAINERS: i2c: drop i2c-pnx maintainer
  MAINTAINERS: i2c: mark also subdirectories as maintained
  i2c: cadence: enable driver for ARM64
  i2c: i801: Document Intel DNV and Broxton
  i2c: at91: manage unexpected RXRDY flag when starting a transfer
  i2c: pnx: Use setup_timer instead of open coding it
  i2c: add ACPI support for I2C mux ports
  acpi: add acpi_preset_companion() stub
  i2c: pxa: Add support for pxa910/988 & new configuration features
  i2c: au1550: Convert to devm_kzalloc and devm_ioremap_resource
  i2c-dev: Fix I2C_SLAVE ioctl comment
  i2c-dev: Fix typo in ioctl name reference
  i2c: sirf: tune the divider to make i2c bus freq more accurate
  i2c: imx: Use -ENXIO as error in the NACK case
  i2c: i801: Add support for Intel Broxton
  i2c: i801: Add support for Intel DNV
  i2c: mediatek: add i2c resume support
  i2c: imx: implement bus recovery
  ...

Documentation/acpi/i2c-muxes.txt

@@ -0,0 +1,58 @@
+ACPI I2C Muxes
+--------------
+
+Describing an I2C device hierarchy that includes I2C muxes requires an ACPI
+Device () scope per mux channel.
+
+Consider this topology:
+
++------+   +------+
+| SMB1 |-->| MUX0 |--CH00--> i2c client A (0x50)
+|      |   | 0x70 |--CH01--> i2c client B (0x50)
++------+   +------+
+
+which corresponds to the following ASL:
+
+Device (SMB1)
+{
+    Name (_HID, ...)
+    Device (MUX0)
+    {
+        Name (_HID, ...)
+        Name (_CRS, ResourceTemplate () {
+            I2cSerialBus (0x70, ControllerInitiated, I2C_SPEED,
+                          AddressingMode7Bit, "^SMB1", 0x00,
+                          ResourceConsumer,,)
+        }
+
+        Device (CH00)
+        {
+            Name (_ADR, 0)
+
+            Device (CLIA)
+            {
+                Name (_HID, ...)
+                Name (_CRS, ResourceTemplate () {
+                    I2cSerialBus (0x50, ControllerInitiated, I2C_SPEED,
+                                  AddressingMode7Bit, "^CH00", 0x00,
+                                  ResourceConsumer,,)
+                }
+            }
+        }
+
+        Device (CH01)
+        {
+            Name (_ADR, 1)
+
+            Device (CLIB)
+            {
+                Name (_HID, ...)
+                Name (_CRS, ResourceTemplate () {
+                    I2cSerialBus (0x50, ControllerInitiated, I2C_SPEED,
+                                  AddressingMode7Bit, "^CH01", 0x00,
+                                  ResourceConsumer,,)
+                }
+            }
+        }
+    }
+}

Documentation/devicetree/bindings/i2c/i2c-davinci.txt

@@ -1,10 +1,10 @@
-* Texas Instruments Davinci I2C
+* Texas Instruments Davinci/Keystone I2C
 
 This file provides information, what the device node for the
-davinci i2c interface contain.
+davinci/keystone i2c interface contains.
 
 Required properties:
-- compatible: "ti,davinci-i2c";
+- compatible: "ti,davinci-i2c" or "ti,keystone-i2c";
 - reg : Offset and length of the register set for the device
 
 Recommended properties :

Documentation/devicetree/bindings/i2c/i2c-imx.txt

@@ -14,6 +14,10 @@ Optional properties:
   The absence of the propoerty indicates the default frequency 100 kHz.
 - dmas: A list of two dma specifiers, one for each entry in dma-names.
 - dma-names: should contain "tx" and "rx".
+- scl-gpios: specify the gpio related to SCL pin
+- sda-gpios: specify the gpio related to SDA pin
+- pinctrl: add extra pinctrl to configure i2c pins to gpio function for i2c
+  bus recovery, call it "gpio" state
 
 Examples:
 
@@ -37,4 +41,9 @@ i2c0: i2c@40066000 { /* i2c0 on vf610 */
 	dmas = <&edma0 0 50>,
 		<&edma0 0 51>;
 	dma-names = "rx","tx";
+	pinctrl-names = "default", "gpio";
+	pinctrl-0 = <&pinctrl_i2c1>;
+	pinctrl-1 = <&pinctrl_i2c1_gpio>;
+	scl-gpios = <&gpio5 26 GPIO_ACTIVE_HIGH>;
+	sda-gpios = <&gpio5 27 GPIO_ACTIVE_HIGH>;
 };

Documentation/devicetree/bindings/i2c/i2c-rcar.txt

@@ -10,6 +10,7 @@ Required properties:
 	"renesas,i2c-r8a7792"
 	"renesas,i2c-r8a7793"
 	"renesas,i2c-r8a7794"
+	"renesas,i2c-r8a7795"
 - reg: physical base address of the controller and length of memory mapped
   region.
 - interrupts: interrupt specifier.

Documentation/devicetree/bindings/i2c/i2c-sh_mobile.txt

@@ -10,6 +10,7 @@ Required properties:
 			- "renesas,iic-r8a7792" (R-Car V2H)
 			- "renesas,iic-r8a7793" (R-Car M2-N)
 			- "renesas,iic-r8a7794" (R-Car E2)
+			- "renesas,iic-r8a7795" (R-Car H3)
 			- "renesas,iic-sh73a0" (SH-Mobile AG5)
 - reg             : address start and address range size of device
 - interrupts      : interrupt of device

Documentation/devicetree/bindings/i2c/i2c-uniphier-f.txt

@@ -0,0 +1,25 @@
+UniPhier I2C controller (FIFO-builtin)
+
+Required properties:
+- compatible: should be "socionext,uniphier-fi2c".
+- #address-cells: should be 1.
+- #size-cells: should be 0.
+- reg: offset and length of the register set for the device.
+- interrupts: a single interrupt specifier.
+- clocks: phandle to the input clock.
+
+Optional properties:
+- clock-frequency: desired I2C bus frequency in Hz.  The maximum supported
+  value is 400000.  Defaults to 100000 if not specified.
+
+Examples:
+
+	i2c0: i2c@58780000 {
+		compatible = "socionext,uniphier-fi2c";
+		reg = <0x58780000 0x80>;
+		#address-cells = <1>;
+		#size-cells = <0>;
+		interrupts = <0 41 4>;
+		clocks = <&i2c_clk>;
+		clock-frequency = <100000>;
+	};

Documentation/devicetree/bindings/i2c/i2c-uniphier.txt

@@ -0,0 +1,25 @@
+UniPhier I2C controller (FIFO-less)
+
+Required properties:
+- compatible: should be "socionext,uniphier-i2c".
+- #address-cells: should be 1.
+- #size-cells: should be 0.
+- reg: offset and length of the register set for the device.
+- interrupts: a single interrupt specifier.
+- clocks: phandle to the input clock.
+
+Optional properties:
+- clock-frequency: desired I2C bus frequency in Hz.  The maximum supported
+  value is 400000.  Defaults to 100000 if not specified.
+
+Examples:
+
+	i2c0: i2c@58400000 {
+		compatible = "socionext,uniphier-i2c";
+		reg = <0x58400000 0x40>;
+		#address-cells = <1>;
+		#size-cells = <0>;
+		interrupts = <0 41 1>;
+		clocks = <&i2c_clk>;
+		clock-frequency = <100000>;
+	};

Documentation/i2c/busses/i2c-i801

@@ -30,6 +30,8 @@ Supported adapters:
   * Intel BayTrail (SOC)
   * Intel Sunrise Point-H (PCH)
   * Intel Sunrise Point-LP (PCH)
+  * Intel DNV (SOC)
+  * Intel Broxton (SOC)
    Datasheets: Publicly available at the Intel website
 
 On Intel Patsburg and later chipsets, both the normal host SMBus controller

MAINTAINERS

@@ -1626,6 +1626,7 @@ L:	linux-arm-kernel@lists.infradead.org (moderated for non-subscribers)
 S:	Maintained
 F:	arch/arm/boot/dts/uniphier*
 F:	arch/arm/mach-uniphier/
+F:	drivers/i2c/busses/i2c-uniphier*
 F:	drivers/pinctrl/uniphier/
 F:	drivers/tty/serial/8250/8250_uniphier.c
 N:	uniphier
@@ -5163,6 +5164,7 @@ S:	Maintained
 F:	Documentation/devicetree/bindings/i2c/
 F:	Documentation/i2c/
 F:	drivers/i2c/
+F:	drivers/i2c/*/
 F:	include/linux/i2c.h
 F:	include/linux/i2c-*.h
 F:	include/uapi/linux/i2c.h
@@ -8418,12 +8420,6 @@ M:	"Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
 S:	Maintained
 F:	drivers/pnp/
 
-PNXxxxx I2C DRIVER
-M:	Vitaly Wool <vitalywool@gmail.com>
-L:	linux-i2c@vger.kernel.org
-S:	Maintained
-F:	drivers/i2c/busses/i2c-pnx.c
-
 PPP PROTOCOL DRIVERS AND COMPRESSORS
 M:	Paul Mackerras <paulus@samba.org>
 L:	linux-ppp@vger.kernel.org

drivers/i2c/busses/Kconfig

@@ -124,6 +124,8 @@ config I2C_I801
 	    BayTrail (SOC)
 	    Sunrise Point-H (PCH)
 	    Sunrise Point-LP (PCH)
+	    DNV (SOC)
+	    Broxton (SOC)
 
 	  This driver can also be built as a module.  If so, the module
 	  will be called i2c-i801.
@@ -422,7 +424,7 @@ config I2C_BLACKFIN_TWI_CLK_KHZ
 
 config I2C_CADENCE
 	tristate "Cadence I2C Controller"
-	depends on ARCH_ZYNQ
+	depends on ARCH_ZYNQ || ARM64
 	help
 	  Say yes here to select Cadence I2C Host Controller. This controller is
 	  e.g. used by Xilinx Zynq.
@@ -582,10 +584,10 @@ config I2C_IMG
 
 config I2C_IMX
 	tristate "IMX I2C interface"
-	depends on ARCH_MXC
+	depends on ARCH_MXC || ARCH_LAYERSCAPE
 	help
 	  Say Y here if you want to use the IIC bus controller on
-	  the Freescale i.MX/MXC processors.
+	  the Freescale i.MX/MXC or Layerscape processors.
 
 	  This driver can also be built as a module.  If so, the module
 	  will be called i2c-imx.
@@ -902,6 +904,22 @@ config I2C_TEGRA
 	  If you say yes to this option, support will be included for the
 	  I2C controller embedded in NVIDIA Tegra SOCs
 
+config I2C_UNIPHIER
+	tristate "UniPhier FIFO-less I2C controller"
+	depends on ARCH_UNIPHIER
+	help
+	  If you say yes to this option, support will be included for
+	  the UniPhier FIFO-less I2C interface embedded in PH1-LD4, PH1-sLD8,
+	  or older UniPhier SoCs.
+
+config I2C_UNIPHIER_F
+	tristate "UniPhier FIFO-builtin I2C controller"
+	depends on ARCH_UNIPHIER
+	help
+	  If you say yes to this option, support will be included for
+	  the UniPhier FIFO-builtin I2C interface embedded in PH1-Pro4,
+	  PH1-Pro5, or newer UniPhier SoCs.
+
 config I2C_VERSATILE
 	tristate "ARM Versatile/Realview I2C bus support"
 	depends on ARCH_VERSATILE || ARCH_REALVIEW || ARCH_VEXPRESS

drivers/i2c/busses/Makefile

@@ -87,6 +87,8 @@ obj-$(CONFIG_I2C_ST)		+= i2c-st.o
 obj-$(CONFIG_I2C_STU300)	+= i2c-stu300.o
 obj-$(CONFIG_I2C_SUN6I_P2WI)	+= i2c-sun6i-p2wi.o
 obj-$(CONFIG_I2C_TEGRA)		+= i2c-tegra.o
+obj-$(CONFIG_I2C_UNIPHIER)	+= i2c-uniphier.o
+obj-$(CONFIG_I2C_UNIPHIER_F)	+= i2c-uniphier-f.o
 obj-$(CONFIG_I2C_VERSATILE)	+= i2c-versatile.o
 obj-$(CONFIG_I2C_WMT)		+= i2c-wmt.o
 obj-$(CONFIG_I2C_OCTEON)	+= i2c-octeon.o

drivers/i2c/busses/i2c-at91.c

@@ -347,8 +347,14 @@ error:
 
 static void at91_twi_read_next_byte(struct at91_twi_dev *dev)
 {
-	if (!dev->buf_len)
+	/*
+	 * If we are in this case, it means there is garbage data in RHR, so
+	 * delete them.
+	 */
+	if (!dev->buf_len) {
+		at91_twi_read(dev, AT91_TWI_RHR);
 		return;
+	}
 
 	/* 8bit read works with and without FIFO */
 	*dev->buf = readb_relaxed(dev->base + AT91_TWI_RHR);
@@ -465,19 +471,73 @@ static irqreturn_t atmel_twi_interrupt(int irq, void *dev_id)
 
 	if (!irqstatus)
 		return IRQ_NONE;
-	else if (irqstatus & AT91_TWI_RXRDY)
+	/*
+	 * In reception, the behavior of the twi device (before sama5d2) is
+	 * weird. There is some magic about RXRDY flag! When a data has been
+	 * almost received, the reception of a new one is anticipated if there
+	 * is no stop command to send. That is the reason why ask for sending
+	 * the stop command not on the last data but on the second last one.
+	 *
+	 * Unfortunately, we could still have the RXRDY flag set even if the
+	 * transfer is done and we have read the last data. It might happen
+	 * when the i2c slave device sends too quickly data after receiving the
+	 * ack from the master. The data has been almost received before having
+	 * the order to send stop. In this case, sending the stop command could
+	 * cause a RXRDY interrupt with a TXCOMP one. It is better to manage
+	 * the RXRDY interrupt first in order to not keep garbage data in the
+	 * Receive Holding Register for the next transfer.
+	 */
+	if (irqstatus & AT91_TWI_RXRDY)
 		at91_twi_read_next_byte(dev);
-	else if (irqstatus & AT91_TWI_TXRDY)
-		at91_twi_write_next_byte(dev);
-
-	/* catch error flags */
-	dev->transfer_status |= status;
 
+	/*
+	 * When a NACK condition is detected, the I2C controller sets the NACK,
+	 * TXCOMP and TXRDY bits all together in the Status Register (SR).
+	 *
+	 * 1 - Handling NACK errors with CPU write transfer.
+	 *
+	 * In such case, we should not write the next byte into the Transmit
+	 * Holding Register (THR) otherwise the I2C controller would start a new
+	 * transfer and the I2C slave is likely to reply by another NACK.
+	 *
+	 * 2 - Handling NACK errors with DMA write transfer.
+	 *
+	 * By setting the TXRDY bit in the SR, the I2C controller also triggers
+	 * the DMA controller to write the next data into the THR. Then the
+	 * result depends on the hardware version of the I2C controller.
+	 *
+	 * 2a - Without support of the Alternative Command mode.
+	 *
+	 * This is the worst case: the DMA controller is triggered to write the
+	 * next data into the THR, hence starting a new transfer: the I2C slave
+	 * is likely to reply by another NACK.
+	 * Concurrently, this interrupt handler is likely to be called to manage
+	 * the first NACK before the I2C controller detects the second NACK and
+	 * sets once again the NACK bit into the SR.
+	 * When handling the first NACK, this interrupt handler disables the I2C
+	 * controller interruptions, especially the NACK interrupt.
+	 * Hence, the NACK bit is pending into the SR. This is why we should
+	 * read the SR to clear all pending interrupts at the beginning of
+	 * at91_do_twi_transfer() before actually starting a new transfer.
+	 *
+	 * 2b - With support of the Alternative Command mode.
+	 *
+	 * When a NACK condition is detected, the I2C controller also locks the
+	 * THR (and sets the LOCK bit in the SR): even though the DMA controller
+	 * is triggered by the TXRDY bit to write the next data into the THR,
+	 * this data actually won't go on the I2C bus hence a second NACK is not
+	 * generated.
+	 */
 	if (irqstatus & (AT91_TWI_TXCOMP | AT91_TWI_NACK)) {
 		at91_disable_twi_interrupts(dev);
 		complete(&dev->cmd_complete);
+	} else if (irqstatus & AT91_TWI_TXRDY) {
+		at91_twi_write_next_byte(dev);
 	}
 
+	/* catch error flags */
+	dev->transfer_status |= status;
+
 	return IRQ_HANDLED;
 }
 
@@ -537,6 +597,9 @@ static int at91_do_twi_transfer(struct at91_twi_dev *dev)
 	reinit_completion(&dev->cmd_complete);
 	dev->transfer_status = 0;
 
+	/* Clear pending interrupts, such as NACK. */
+	at91_twi_read(dev, AT91_TWI_SR);
+
 	if (dev->fifo_size) {
 		unsigned fifo_mr = at91_twi_read(dev, AT91_TWI_FMR);
 
@@ -558,11 +621,6 @@ static int at91_do_twi_transfer(struct at91_twi_dev *dev)
 	} else if (dev->msg->flags & I2C_M_RD) {
 		unsigned start_flags = AT91_TWI_START;
 
-		if (at91_twi_read(dev, AT91_TWI_SR) & AT91_TWI_RXRDY) {
-			dev_err(dev->dev, "RXRDY still set!");
-			at91_twi_read(dev, AT91_TWI_RHR);
-		}
-
 		/* if only one byte is to be read, immediately stop transfer */
 		if (!has_alt_cmd && dev->buf_len <= 1 &&
 		    !(dev->msg->flags & I2C_M_RECV_LEN))

drivers/i2c/busses/i2c-au1550.c

@@ -48,7 +48,6 @@ struct i2c_au1550_data {
 	void __iomem *psc_base;
 	int	xfer_timeout;
 	struct i2c_adapter adap;
-	struct resource *ioarea;
 };
 
 static inline void WR(struct i2c_au1550_data *a, int r, unsigned long v)
@@ -284,10 +283,10 @@ static void i2c_au1550_setup(struct i2c_au1550_data *priv)
 	/* Set the protocol timer values.  See Table 71 in the
 	 * Au1550 Data Book for standard timing values.
 	 */
-	WR(priv, PSC_SMBTMR, PSC_SMBTMR_SET_TH(0) | PSC_SMBTMR_SET_PS(15) | \
-		PSC_SMBTMR_SET_PU(15) | PSC_SMBTMR_SET_SH(15) | \
-		PSC_SMBTMR_SET_SU(15) | PSC_SMBTMR_SET_CL(15) | \
-		PSC_SMBTMR_SET_CH(15));
+	WR(priv, PSC_SMBTMR, PSC_SMBTMR_SET_TH(0) | PSC_SMBTMR_SET_PS(20) | \
+		PSC_SMBTMR_SET_PU(20) | PSC_SMBTMR_SET_SH(20) | \
+		PSC_SMBTMR_SET_SU(20) | PSC_SMBTMR_SET_CL(20) | \
+		PSC_SMBTMR_SET_CH(20));
 
 	cfg |= PSC_SMBCFG_DE_ENABLE;
 	WR(priv, PSC_SMBCFG, cfg);
@@ -315,30 +314,16 @@ i2c_au1550_probe(struct platform_device *pdev)
 	struct resource *r;
 	int ret;
 
-	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	if (!r) {
-		ret = -ENODEV;
-		goto out;
-	}
+	priv = devm_kzalloc(&pdev->dev, sizeof(struct i2c_au1550_data),
+			    GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
 
-	priv = kzalloc(sizeof(struct i2c_au1550_data), GFP_KERNEL);
-	if (!priv) {
-		ret = -ENOMEM;
-		goto out;
-	}
-
-	priv->ioarea = request_mem_region(r->start, resource_size(r),
-					  pdev->name);
-	if (!priv->ioarea) {
-		ret = -EBUSY;
-		goto out_mem;
-	}
+	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	priv->psc_base = devm_ioremap_resource(&pdev->dev, r);
+	if (IS_ERR(priv->psc_base))
+		return PTR_ERR(priv->psc_base);
 
-	priv->psc_base = ioremap(r->start, resource_size(r));
-	if (!priv->psc_base) {
-		ret = -EIO;
-		goto out_map;
-	}
 	priv->xfer_timeout = 200;
 
 	priv->adap.nr = pdev->id;
@@ -351,20 +336,13 @@ i2c_au1550_probe(struct platform_device *pdev)
 	i2c_au1550_setup(priv);
 
 	ret = i2c_add_numbered_adapter(&priv->adap);
-	if (ret == 0) {
-		platform_set_drvdata(pdev, priv);
-		return 0;
+	if (ret) {
+		i2c_au1550_disable(priv);
+		return ret;
 	}
 
-	i2c_au1550_disable(priv);
-	iounmap(priv->psc_base);
-out_map:
-	release_resource(priv->ioarea);
-	kfree(priv->ioarea);
-out_mem:
-	kfree(priv);
-out:
-	return ret;
+	platform_set_drvdata(pdev, priv);
+	return 0;
 }
 
 static int i2c_au1550_remove(struct platform_device *pdev)
@@ -373,10 +351,6 @@ static int i2c_au1550_remove(struct platform_device *pdev)
 
 	i2c_del_adapter(&priv->adap);
 	i2c_au1550_disable(priv);
-	iounmap(priv->psc_base);
-	release_resource(priv->ioarea);
-	kfree(priv->ioarea);
-	kfree(priv);
 	return 0;
 }
 

drivers/i2c/busses/i2c-davinci.c

@@ -181,6 +181,7 @@ static void i2c_davinci_calc_clk_dividers(struct davinci_i2c_dev *dev)
 	u32 clkh;
 	u32 clkl;
 	u32 input_clock = clk_get_rate(dev->clk);
+	struct device_node *of_node = dev->dev->of_node;
 
 	/* NOTE: I2C Clock divider programming info
 	 * As per I2C specs the following formulas provide prescaler
@@ -196,6 +197,9 @@ static void i2c_davinci_calc_clk_dividers(struct davinci_i2c_dev *dev)
 	 * where if PSC == 0, d = 7,
 	 *       if PSC == 1, d = 6
 	 *       if PSC > 1 , d = 5
+	 *
+	 * Note:
+	 * d is always 6 on Keystone I2C controller
 	 */
 
 	/* get minimum of 7 MHz clock, but max of 12 MHz */
@@ -204,6 +208,9 @@ static void i2c_davinci_calc_clk_dividers(struct davinci_i2c_dev *dev)
 		psc++;	/* better to run under spec than over */
 	d = (psc >= 2) ? 5 : 7 - psc;
 
+	if (of_node && of_device_is_compatible(of_node, "ti,keystone-i2c"))
+		d = 6;
+
 	clk = ((input_clock / (psc + 1)) / (pdata->bus_freq * 1000));
 	/* Avoid driving the bus too fast because of rounding errors above */
 	if (input_clock / (psc + 1) / clk > pdata->bus_freq * 1000)
@@ -726,6 +733,7 @@ static struct i2c_algorithm i2c_davinci_algo = {
 
 static const struct of_device_id davinci_i2c_of_match[] = {
 	{.compatible = "ti,davinci-i2c", },
+	{.compatible = "ti,keystone-i2c", },
 	{},
 };
 MODULE_DEVICE_TABLE(of, davinci_i2c_of_match);

drivers/i2c/busses/i2c-designware-core.c

@@ -165,7 +165,7 @@ static char *abort_sources[] = {
 		"lost arbitration",
 };
 
-u32 dw_readl(struct dw_i2c_dev *dev, int offset)
+static u32 dw_readl(struct dw_i2c_dev *dev, int offset)
 {
 	u32 value;
 
@@ -181,7 +181,7 @@ u32 dw_readl(struct dw_i2c_dev *dev, int offset)
 		return value;
 }
 
-void dw_writel(struct dw_i2c_dev *dev, u32 b, int offset)
+static void dw_writel(struct dw_i2c_dev *dev, u32 b, int offset)
 {
 	if (dev->accessor_flags & ACCESS_SWAP)
 		b = swab32(b);
@@ -438,7 +438,7 @@ static void i2c_dw_xfer_init(struct dw_i2c_dev *dev)
 	__i2c_dw_enable(dev, true);
 
 	/* Clear and enable interrupts */
-	i2c_dw_clear_int(dev);
+	dw_readl(dev, DW_IC_CLR_INTR);
 	dw_writel(dev, DW_IC_INTR_DEFAULT_MASK, DW_IC_INTR_MASK);
 }
 
@@ -618,7 +618,7 @@ static int i2c_dw_handle_tx_abort(struct dw_i2c_dev *dev)
 /*
  * Prepare controller for a transaction and call i2c_dw_xfer_msg
  */
-int
+static int
 i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
 {
 	struct dw_i2c_dev *dev = i2c_get_adapdata(adap);
@@ -702,14 +702,17 @@ done_nolock:
 
 	return ret;
 }
-EXPORT_SYMBOL_GPL(i2c_dw_xfer);
 
-u32 i2c_dw_func(struct i2c_adapter *adap)
+static u32 i2c_dw_func(struct i2c_adapter *adap)
 {
 	struct dw_i2c_dev *dev = i2c_get_adapdata(adap);
 	return dev->functionality;
 }
-EXPORT_SYMBOL_GPL(i2c_dw_func);
+
+static struct i2c_algorithm i2c_dw_algo = {
+	.master_xfer	= i2c_dw_xfer,
+	.functionality	= i2c_dw_func,
+};
 
 static u32 i2c_dw_read_clear_intrbits(struct dw_i2c_dev *dev)
 {
@@ -770,7 +773,7 @@ static u32 i2c_dw_read_clear_intrbits(struct dw_i2c_dev *dev)
  * Interrupt service routine. This gets called whenever an I2C interrupt
  * occurs.
  */
-irqreturn_t i2c_dw_isr(int this_irq, void *dev_id)
+static irqreturn_t i2c_dw_isr(int this_irq, void *dev_id)
 {
 	struct dw_i2c_dev *dev = dev_id;
 	u32 stat, enabled;
@@ -813,20 +816,6 @@ tx_aborted:
 
 	return IRQ_HANDLED;
 }
-EXPORT_SYMBOL_GPL(i2c_dw_isr);
-
-void i2c_dw_enable(struct dw_i2c_dev *dev)
-{
-       /* Enable the adapter */
-	__i2c_dw_enable(dev, true);
-}
-EXPORT_SYMBOL_GPL(i2c_dw_enable);
-
-u32 i2c_dw_is_enabled(struct dw_i2c_dev *dev)
-{
-	return dw_readl(dev, DW_IC_ENABLE);
-}
-EXPORT_SYMBOL_GPL(i2c_dw_is_enabled);
 
 void i2c_dw_disable(struct dw_i2c_dev *dev)
 {
@@ -839,12 +828,6 @@ void i2c_dw_disable(struct dw_i2c_dev *dev)
 }
 EXPORT_SYMBOL_GPL(i2c_dw_disable);
 
-void i2c_dw_clear_int(struct dw_i2c_dev *dev)
-{
-	dw_readl(dev, DW_IC_CLR_INTR);
-}
-EXPORT_SYMBOL_GPL(i2c_dw_clear_int);
-
 void i2c_dw_disable_int(struct dw_i2c_dev *dev)
 {
 	dw_writel(dev, 0, DW_IC_INTR_MASK);
@@ -857,5 +840,40 @@ u32 i2c_dw_read_comp_param(struct dw_i2c_dev *dev)
 }
 EXPORT_SYMBOL_GPL(i2c_dw_read_comp_param);
 
+int i2c_dw_probe(struct dw_i2c_dev *dev)
+{
+	struct i2c_adapter *adap = &dev->adapter;
+	int r;
+
+	init_completion(&dev->cmd_complete);
+	mutex_init(&dev->lock);
+
+	r = i2c_dw_init(dev);
+	if (r)
+		return r;
+
+	snprintf(adap->name, sizeof(adap->name),
+		 "Synopsys DesignWare I2C adapter");
+	adap->algo = &i2c_dw_algo;
+	adap->dev.parent = dev->dev;
+	i2c_set_adapdata(adap, dev);
+
+	i2c_dw_disable_int(dev);
+	r = devm_request_irq(dev->dev, dev->irq, i2c_dw_isr, IRQF_SHARED,
+			     dev_name(dev->dev), dev);
+	if (r) {
+		dev_err(dev->dev, "failure requesting irq %i: %d\n",
+			dev->irq, r);
+		return r;
+	}
+
+	r = i2c_add_numbered_adapter(adap);
+	if (r)
+		dev_err(dev->dev, "failure adding adapter: %d\n", r);
+
+	return r;
+}
+EXPORT_SYMBOL_GPL(i2c_dw_probe);
+
 MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter core");
 MODULE_LICENSE("GPL");

drivers/i2c/busses/i2c-designware-core.h

@@ -112,19 +112,11 @@ struct dw_i2c_dev {
 #define ACCESS_SWAP		0x00000001
 #define ACCESS_16BIT		0x00000002
 
-extern u32 dw_readl(struct dw_i2c_dev *dev, int offset);
-extern void dw_writel(struct dw_i2c_dev *dev, u32 b, int offset);
 extern int i2c_dw_init(struct dw_i2c_dev *dev);
-extern int i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[],
-		int num);
-extern u32 i2c_dw_func(struct i2c_adapter *adap);
-extern irqreturn_t i2c_dw_isr(int this_irq, void *dev_id);
-extern void i2c_dw_enable(struct dw_i2c_dev *dev);
-extern u32 i2c_dw_is_enabled(struct dw_i2c_dev *dev);
 extern void i2c_dw_disable(struct dw_i2c_dev *dev);
-extern void i2c_dw_clear_int(struct dw_i2c_dev *dev);
 extern void i2c_dw_disable_int(struct dw_i2c_dev *dev);
 extern u32 i2c_dw_read_comp_param(struct dw_i2c_dev *dev);
+extern int i2c_dw_probe(struct dw_i2c_dev *dev);
 
 #if IS_ENABLED(CONFIG_I2C_DESIGNWARE_BAYTRAIL)
 extern int i2c_dw_eval_lock_support(struct dw_i2c_dev *dev);

drivers/i2c/busses/i2c-designware-pcidrv.c

@@ -35,6 +35,7 @@
 #include <linux/slab.h>
 #include <linux/pci.h>
 #include <linux/pm_runtime.h>
+#include <linux/acpi.h>
 #include "i2c-designware-core.h"
 
 #define DRIVER_NAME "i2c-designware-pci"
@@ -158,11 +159,6 @@ static struct dw_pci_controller dw_pci_controllers[] = {
 	},
 };
 
-static struct i2c_algorithm i2c_dw_algo = {
-	.master_xfer	= i2c_dw_xfer,
-	.functionality	= i2c_dw_func,
-};
-
 #ifdef CONFIG_PM
 static int i2c_dw_pci_suspend(struct device *dev)
 {
@@ -222,13 +218,12 @@ static int i2c_dw_pci_probe(struct pci_dev *pdev,
 	if (!dev)
 		return -ENOMEM;
 
-	init_completion(&dev->cmd_complete);
-	mutex_init(&dev->lock);
 	dev->clk = NULL;
 	dev->controller = controller;
 	dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;
 	dev->base = pcim_iomap_table(pdev)[0];
 	dev->dev = &pdev->dev;
+	dev->irq = pdev->irq;
 	dev->functionality = controller->functionality |
 				DW_DEFAULT_FUNCTIONALITY;
 
@@ -246,34 +241,16 @@ static int i2c_dw_pci_probe(struct pci_dev *pdev,
 
 	dev->tx_fifo_depth = controller->tx_fifo_depth;
 	dev->rx_fifo_depth = controller->rx_fifo_depth;
-	r = i2c_dw_init(dev);
-	if (r)
-		return r;
 
 	adap = &dev->adapter;
-	i2c_set_adapdata(adap, dev);
 	adap->owner = THIS_MODULE;
 	adap->class = 0;
-	adap->algo = &i2c_dw_algo;
-	adap->dev.parent = &pdev->dev;
+	ACPI_COMPANION_SET(&adap->dev, ACPI_COMPANION(&pdev->dev));
 	adap->nr = controller->bus_num;
 
-	snprintf(adap->name, sizeof(adap->name), "i2c-designware-pci");
-
-	r = devm_request_irq(&pdev->dev, pdev->irq, i2c_dw_isr,
-			IRQF_SHARED | IRQF_COND_SUSPEND, adap->name, dev);
-	if (r) {
-		dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq);
-		return r;
-	}
-
-	i2c_dw_disable_int(dev);
-	i2c_dw_clear_int(dev);
-	r = i2c_add_numbered_adapter(adap);
-	if (r) {
-		dev_err(&pdev->dev, "failure adding adapter\n");
+	r = i2c_dw_probe(dev);
+	if (r)
 		return r;
-	}
 
 	pm_runtime_set_autosuspend_delay(&pdev->dev, 1000);
 	pm_runtime_use_autosuspend(&pdev->dev);

drivers/i2c/busses/i2c-designware-platdrv.c

@@ -42,10 +42,6 @@
 #include <linux/platform_data/i2c-designware.h>
 #include "i2c-designware-core.h"
 
-static struct i2c_algorithm i2c_dw_algo = {
-	.master_xfer	= i2c_dw_xfer,
-	.functionality	= i2c_dw_func,
-};
 static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
 {
 	return clk_get_rate(dev->clk)/1000;
@@ -97,7 +93,6 @@ static void dw_i2c_acpi_params(struct platform_device *pdev, char method[],
 static int dw_i2c_acpi_configure(struct platform_device *pdev)
 {
 	struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
-	const struct acpi_device_id *id;
 
 	dev->adapter.nr = -1;
 	dev->tx_fifo_depth = 32;
@@ -111,29 +106,9 @@ static int dw_i2c_acpi_configure(struct platform_device *pdev)
 	dw_i2c_acpi_params(pdev, "FMCN", &dev->fs_hcnt, &dev->fs_lcnt,
 			   &dev->sda_hold_time);
 
-	/*
-	 * Provide a way for Designware I2C host controllers that are not
-	 * based on Intel LPSS to specify their input clock frequency via
-	 * id->driver_data.
-	 */
-	id = acpi_match_device(pdev->dev.driver->acpi_match_table, &pdev->dev);
-	if (id && id->driver_data)
-		clk_register_fixed_rate(&pdev->dev, dev_name(&pdev->dev), NULL,
-					CLK_IS_ROOT, id->driver_data);
-
 	return 0;
 }
 
-static void dw_i2c_acpi_unconfigure(struct platform_device *pdev)
-{
-	struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
-	const struct acpi_device_id *id;
-
-	id = acpi_match_device(pdev->dev.driver->acpi_match_table, &pdev->dev);
-	if (id && id->driver_data)
-		clk_unregister(dev->clk);
-}
-
 static const struct acpi_device_id dw_i2c_acpi_match[] = {
 	{ "INT33C2", 0 },
 	{ "INT33C3", 0 },
@@ -141,7 +116,7 @@ static const struct acpi_device_id dw_i2c_acpi_match[] = {
 	{ "INT3433", 0 },
 	{ "80860F41", 0 },
 	{ "808622C1", 0 },
-	{ "AMD0010", 133 * 1000 * 1000 },
+	{ "AMD0010", 0 },
 	{ }
 };
 MODULE_DEVICE_TABLE(acpi, dw_i2c_acpi_match);
@@ -150,10 +125,9 @@ static inline int dw_i2c_acpi_configure(struct platform_device *pdev)
 {
 	return -ENODEV;
 }
-static inline void dw_i2c_acpi_unconfigure(struct platform_device *pdev) { }
 #endif
 
-static int dw_i2c_probe(struct platform_device *pdev)
+static int dw_i2c_plat_probe(struct platform_device *pdev)
 {
 	struct dw_i2c_dev *dev;
 	struct i2c_adapter *adap;
@@ -175,8 +149,6 @@ static int dw_i2c_probe(struct platform_device *pdev)
 	if (IS_ERR(dev->base))
 		return PTR_ERR(dev->base);
 
-	init_completion(&dev->cmd_complete);
-	mutex_init(&dev->lock);
 	dev->dev = &pdev->dev;
 	dev->irq = irq;
 	platform_set_drvdata(pdev, dev);
@@ -251,26 +223,11 @@ static int dw_i2c_probe(struct platform_device *pdev)
 		dev->rx_fifo_depth = ((param1 >> 8)  & 0xff) + 1;
 		dev->adapter.nr = pdev->id;
 	}
-	r = i2c_dw_init(dev);
-	if (r)
-		return r;
-
-	i2c_dw_disable_int(dev);
-	r = devm_request_irq(&pdev->dev, dev->irq, i2c_dw_isr, IRQF_SHARED,
-			pdev->name, dev);
-	if (r) {
-		dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq);
-		return r;
-	}
 
 	adap = &dev->adapter;
-	i2c_set_adapdata(adap, dev);
 	adap->owner = THIS_MODULE;
 	adap->class = I2C_CLASS_DEPRECATED;
-	strlcpy(adap->name, "Synopsys DesignWare I2C adapter",
-			sizeof(adap->name));
-	adap->algo = &i2c_dw_algo;
-	adap->dev.parent = &pdev->dev;
+	ACPI_COMPANION_SET(&adap->dev, ACPI_COMPANION(&pdev->dev));
 	adap->dev.of_node = pdev->dev.of_node;
 
 	if (dev->pm_runtime_disabled) {
@@ -282,9 +239,8 @@ static int dw_i2c_probe(struct platform_device *pdev)
 		pm_runtime_enable(&pdev->dev);
 	}
 
-	r = i2c_add_numbered_adapter(adap);
+	r = i2c_dw_probe(dev);
 	if (r) {
-		dev_err(&pdev->dev, "failure adding adapter\n");
 		pm_runtime_disable(&pdev->dev);
 		return r;
 	}
@@ -292,7 +248,7 @@ static int dw_i2c_probe(struct platform_device *pdev)
 	return 0;
 }
 
-static int dw_i2c_remove(struct platform_device *pdev)
+static int dw_i2c_plat_remove(struct platform_device *pdev)
 {
 	struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
 
@@ -306,9 +262,6 @@ static int dw_i2c_remove(struct platform_device *pdev)
 	pm_runtime_put_sync(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
 
-	if (has_acpi_companion(&pdev->dev))
-		dw_i2c_acpi_unconfigure(pdev);
-
 	return 0;
 }
 
@@ -321,23 +274,23 @@ MODULE_DEVICE_TABLE(of, dw_i2c_of_match);
 #endif
 
 #ifdef CONFIG_PM_SLEEP
-static int dw_i2c_prepare(struct device *dev)
+static int dw_i2c_plat_prepare(struct device *dev)
 {
 	return pm_runtime_suspended(dev);
 }
 
-static void dw_i2c_complete(struct device *dev)
+static void dw_i2c_plat_complete(struct device *dev)
 {
 	if (dev->power.direct_complete)
 		pm_request_resume(dev);
 }
 #else
-#define dw_i2c_prepare	NULL
-#define dw_i2c_complete	NULL
+#define dw_i2c_plat_prepare	NULL
+#define dw_i2c_plat_complete	NULL
 #endif
 
 #ifdef CONFIG_PM
-static int dw_i2c_suspend(struct device *dev)
+static int dw_i2c_plat_suspend(struct device *dev)
 {
 	struct platform_device *pdev = to_platform_device(dev);
 	struct dw_i2c_dev *i_dev = platform_get_drvdata(pdev);
@@ -348,7 +301,7 @@ static int dw_i2c_suspend(struct device *dev)
 	return 0;
 }
 
-static int dw_i2c_resume(struct device *dev)
+static int dw_i2c_plat_resume(struct device *dev)
 {
 	struct platform_device *pdev = to_platform_device(dev);
 	struct dw_i2c_dev *i_dev = platform_get_drvdata(pdev);
@@ -362,10 +315,10 @@ static int dw_i2c_resume(struct device *dev)
 }
 
 static const struct dev_pm_ops dw_i2c_dev_pm_ops = {
-	.prepare = dw_i2c_prepare,
-	.complete = dw_i2c_complete,
-	SET_SYSTEM_SLEEP_PM_OPS(dw_i2c_suspend, dw_i2c_resume)
-	SET_RUNTIME_PM_OPS(dw_i2c_suspend, dw_i2c_resume, NULL)
+	.prepare = dw_i2c_plat_prepare,
+	.complete = dw_i2c_plat_complete,
+	SET_SYSTEM_SLEEP_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume)
+	SET_RUNTIME_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume, NULL)
 };
 
 #define DW_I2C_DEV_PMOPS (&dw_i2c_dev_pm_ops)
@@ -377,8 +330,8 @@ static const struct dev_pm_ops dw_i2c_dev_pm_ops = {
 MODULE_ALIAS("platform:i2c_designware");
 
 static struct platform_driver dw_i2c_driver = {
-	.probe = dw_i2c_probe,
-	.remove = dw_i2c_remove,
+	.probe = dw_i2c_plat_probe,
+	.remove = dw_i2c_plat_remove,
 	.driver		= {
 		.name	= "i2c_designware",
 		.of_match_table = of_match_ptr(dw_i2c_of_match),

drivers/i2c/busses/i2c-i801.c

@@ -60,6 +60,8 @@
  * BayTrail (SOC)		0x0f12	32	hard	yes	yes	yes
  * Sunrise Point-H (PCH) 	0xa123  32	hard	yes	yes	yes
  * Sunrise Point-LP (PCH)	0x9d23	32	hard	yes	yes	yes
+ * DNV (SOC)			0x19df	32	hard	yes	yes	yes
+ * Broxton (SOC)		0x5ad4	32	hard	yes	yes	yes
  *
  * Features supported by this driver:
  * Software PEC				no
@@ -202,6 +204,8 @@
 #define PCI_DEVICE_ID_INTEL_WILDCATPOINT_LP_SMBUS	0x9ca2
 #define PCI_DEVICE_ID_INTEL_SUNRISEPOINT_H_SMBUS	0xa123
 #define PCI_DEVICE_ID_INTEL_SUNRISEPOINT_LP_SMBUS	0x9d23
+#define PCI_DEVICE_ID_INTEL_DNV_SMBUS			0x19df
+#define PCI_DEVICE_ID_INTEL_BROXTON_SMBUS		0x5ad4
 
 struct i801_mux_config {
 	char *gpio_chip;
@@ -863,6 +867,8 @@ static const struct pci_device_id i801_ids[] = {
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_BRASWELL_SMBUS) },
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SUNRISEPOINT_H_SMBUS) },
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SUNRISEPOINT_LP_SMBUS) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_DNV_SMBUS) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_BROXTON_SMBUS) },
 	{ 0, }
 };
 
@@ -1251,11 +1257,15 @@ static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
 	priv->adapter.owner = THIS_MODULE;
 	priv->adapter.class = i801_get_adapter_class(priv);
 	priv->adapter.algo = &smbus_algorithm;
+	priv->adapter.dev.parent = &dev->dev;
+	ACPI_COMPANION_SET(&priv->adapter.dev, ACPI_COMPANION(&dev->dev));
+	priv->adapter.retries = 3;
 
 	priv->pci_dev = dev;
 	switch (dev->device) {
 	case PCI_DEVICE_ID_INTEL_SUNRISEPOINT_H_SMBUS:
 	case PCI_DEVICE_ID_INTEL_SUNRISEPOINT_LP_SMBUS:
+	case PCI_DEVICE_ID_INTEL_DNV_SMBUS:
 		priv->features |= FEATURE_I2C_BLOCK_READ;
 		priv->features |= FEATURE_IRQ;
 		priv->features |= FEATURE_SMBUS_PEC;
@@ -1381,12 +1391,6 @@ static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
 
 	i801_add_tco(priv);
 
-	/* set up the sysfs linkage to our parent device */
-	priv->adapter.dev.parent = &dev->dev;
-
-	/* Retry up to 3 times on lost arbitration */
-	priv->adapter.retries = 3;
-
 	snprintf(priv->adapter.name, sizeof(priv->adapter.name),
 		"SMBus I801 adapter at %04lx", priv->smba);
 	err = i2c_add_adapter(&priv->adapter);

drivers/i2c/busses/i2c-ibm_iic.c

@@ -798,6 +798,7 @@ static const struct of_device_id ibm_iic_match[] = {
 	{ .compatible = "ibm,iic", },
 	{}
 };
+MODULE_DEVICE_TABLE(of, ibm_iic_match);
 
 static struct platform_driver ibm_iic_driver = {
 	.driver = {

drivers/i2c/busses/i2c-img-scb.c

@@ -278,8 +278,6 @@
 #define ISR_COMPLETE(err)	(ISR_COMPLETE_M | (ISR_STATUS_M & (err)))
 #define ISR_FATAL(err)		(ISR_COMPLETE(err) | ISR_FATAL_M)
 
-#define REL_SOC_IP_SCB_2_2_1	0x00020201
-
 enum img_i2c_mode {
 	MODE_INACTIVE,
 	MODE_RAW,
@@ -536,6 +534,7 @@ static void img_i2c_read_fifo(struct img_i2c *i2c)
 		u32 fifo_status;
 		u8 data;
 
+		img_i2c_wr_rd_fence(i2c);
 		fifo_status = img_i2c_readl(i2c, SCB_FIFO_STATUS_REG);
 		if (fifo_status & FIFO_READ_EMPTY)
 			break;
@@ -544,7 +543,6 @@ static void img_i2c_read_fifo(struct img_i2c *i2c)
 		*i2c->msg.buf = data;
 
 		img_i2c_writel(i2c, SCB_READ_FIFO_REG, 0xff);
-		img_i2c_wr_rd_fence(i2c);
 		i2c->msg.len--;
 		i2c->msg.buf++;
 	}
@@ -556,12 +554,12 @@ static void img_i2c_write_fifo(struct img_i2c *i2c)
 	while (i2c->msg.len) {
 		u32 fifo_status;
 
+		img_i2c_wr_rd_fence(i2c);
 		fifo_status = img_i2c_readl(i2c, SCB_FIFO_STATUS_REG);
 		if (fifo_status & FIFO_WRITE_FULL)
 			break;
 
 		img_i2c_writel(i2c, SCB_WRITE_DATA_REG, *i2c->msg.buf);
-		img_i2c_wr_rd_fence(i2c);
 		i2c->msg.len--;
 		i2c->msg.buf++;
 	}
@@ -859,7 +857,7 @@ static unsigned int img_i2c_auto(struct img_i2c *i2c,
 	}
 
 	/* Enable transaction halt on start bit */
-	if (!i2c->last_msg && i2c->line_status & LINESTAT_START_BIT_DET) {
+	if (!i2c->last_msg && line_status & LINESTAT_START_BIT_DET) {
 		img_i2c_transaction_halt(i2c, true);
 		/* we're no longer interested in the slave event */
 		i2c->int_enable &= ~INT_SLAVE_EVENT;
@@ -1062,6 +1060,15 @@ static int img_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
 		i2c->last_msg = (i == num - 1);
 		reinit_completion(&i2c->msg_complete);
 
+		/*
+		 * Clear line status and all interrupts before starting a
+		 * transfer, as we may have unserviced interrupts from
+		 * previous transfers that might be handled in the context
+		 * of the new transfer.
+		 */
+		img_i2c_writel(i2c, SCB_INT_CLEAR_REG, ~0);
+		img_i2c_writel(i2c, SCB_CLEAR_REG, ~0);
+
 		if (atomic)
 			img_i2c_atomic_start(i2c);
 		else if (msg->flags & I2C_M_RD)
@@ -1120,13 +1127,8 @@ static int img_i2c_init(struct img_i2c *i2c)
 		return -EINVAL;
 	}
 
-	if (rev == REL_SOC_IP_SCB_2_2_1) {
-		i2c->need_wr_rd_fence = true;
-		dev_info(i2c->adap.dev.parent, "fence quirk enabled");
-	}
-
-	bitrate_khz = i2c->bitrate / 1000;
-	clk_khz = clk_get_rate(i2c->scb_clk) / 1000;
+	/* Fencing enabled by default. */
+	i2c->need_wr_rd_fence = true;
 
 	/* Determine what mode we're in from the bitrate */
 	timing = timings[0];
@@ -1136,6 +1138,17 @@ static int img_i2c_init(struct img_i2c *i2c)
 			break;
 		}
 	}
+	if (i2c->bitrate > timings[ARRAY_SIZE(timings) - 1].max_bitrate) {
+		dev_warn(i2c->adap.dev.parent,
+			 "requested bitrate (%u) is higher than the max bitrate supported (%u)\n",
+			 i2c->bitrate,
+			 timings[ARRAY_SIZE(timings) - 1].max_bitrate);
+		timing = timings[ARRAY_SIZE(timings) - 1];
+		i2c->bitrate = timing.max_bitrate;
+	}
+
+	bitrate_khz = i2c->bitrate / 1000;
+	clk_khz = clk_get_rate(i2c->scb_clk) / 1000;
 
 	/* Find the prescale that would give us that inc (approx delay = 0) */
 	prescale = SCB_OPT_INC * clk_khz / (256 * 16 * bitrate_khz);
@@ -1182,32 +1195,32 @@ static int img_i2c_init(struct img_i2c *i2c)
 	    ((bitrate_khz * clk_period) / 2))
 		int_bitrate++;
 
-	/* Setup TCKH value */
-	tckh = timing.tckh / clk_period;
-	if (timing.tckh % clk_period)
-		tckh++;
+	/*
+	 * Setup clock duty cycle, start with 50% and adjust TCKH and TCKL
+	 * values from there if they don't meet minimum timing requirements
+	 */
+	tckh = int_bitrate / 2;
+	tckl = int_bitrate - tckh;
 
-	if (tckh > 0)
-		data = tckh - 1;
-	else
-		data = 0;
+	/* Adjust TCKH and TCKL values */
+	data = DIV_ROUND_UP(timing.tckl, clk_period);
 
-	img_i2c_writel(i2c, SCB_TIME_TCKH_REG, data);
+	if (tckl < data) {
+		tckl = data;
+		tckh = int_bitrate - tckl;
+	}
 
-	/* Setup TCKL value */
-	tckl = int_bitrate - tckh;
+	if (tckh > 0)
+		--tckh;
 
 	if (tckl > 0)
-		data = tckl - 1;
-	else
-		data = 0;
+		--tckl;
 
-	img_i2c_writel(i2c, SCB_TIME_TCKL_REG, data);
+	img_i2c_writel(i2c, SCB_TIME_TCKH_REG, tckh);
+	img_i2c_writel(i2c, SCB_TIME_TCKL_REG, tckl);
 
 	/* Setup TSDH value */
-	tsdh = timing.tsdh / clk_period;
-	if (timing.tsdh % clk_period)
-		tsdh++;
+	tsdh = DIV_ROUND_UP(timing.tsdh, clk_period);
 
 	if (tsdh > 1)
 		data = tsdh - 1;

drivers/i2c/busses/i2c-imx.c

@@ -49,6 +49,7 @@
 #include <linux/of.h>
 #include <linux/of_device.h>
 #include <linux/of_dma.h>
+#include <linux/of_gpio.h>
 #include <linux/platform_data/i2c-imx.h>
 #include <linux/platform_device.h>
 #include <linux/sched.h>
@@ -207,6 +208,11 @@ struct imx_i2c_struct {
 	unsigned int		cur_clk;
 	unsigned int		bitrate;
 	const struct imx_i2c_hwdata	*hwdata;
+	struct i2c_bus_recovery_info rinfo;
+
+	struct pinctrl *pinctrl;
+	struct pinctrl_state *pinctrl_pins_default;
+	struct pinctrl_state *pinctrl_pins_gpio;
 
 	struct imx_i2c_dma	*dma;
 };
@@ -461,7 +467,7 @@ static int i2c_imx_acked(struct imx_i2c_struct *i2c_imx)
 {
 	if (imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR) & I2SR_RXAK) {
 		dev_dbg(&i2c_imx->adapter.dev, "<%s> No ACK\n", __func__);
-		return -EIO;  /* No ACK */
+		return -ENXIO;  /* No ACK */
 	}
 
 	dev_dbg(&i2c_imx->adapter.dev, "<%s> ACK received\n", __func__);
@@ -896,6 +902,13 @@ static int i2c_imx_xfer(struct i2c_adapter *adapter,
 
 	/* Start I2C transfer */
 	result = i2c_imx_start(i2c_imx);
+	if (result) {
+		if (i2c_imx->adapter.bus_recovery_info) {
+			i2c_recover_bus(&i2c_imx->adapter);
+			result = i2c_imx_start(i2c_imx);
+		}
+	}
+
 	if (result)
 		goto fail0;
 
@@ -956,6 +969,55 @@ fail0:
 	return (result < 0) ? result : num;
 }
 
+static void i2c_imx_prepare_recovery(struct i2c_adapter *adap)
+{
+	struct imx_i2c_struct *i2c_imx;
+
+	i2c_imx = container_of(adap, struct imx_i2c_struct, adapter);
+
+	pinctrl_select_state(i2c_imx->pinctrl, i2c_imx->pinctrl_pins_gpio);
+}
+
+static void i2c_imx_unprepare_recovery(struct i2c_adapter *adap)
+{
+	struct imx_i2c_struct *i2c_imx;
+
+	i2c_imx = container_of(adap, struct imx_i2c_struct, adapter);
+
+	pinctrl_select_state(i2c_imx->pinctrl, i2c_imx->pinctrl_pins_default);
+}
+
+static void i2c_imx_init_recovery_info(struct imx_i2c_struct *i2c_imx,
+		struct platform_device *pdev)
+{
+	struct i2c_bus_recovery_info *rinfo = &i2c_imx->rinfo;
+
+	i2c_imx->pinctrl_pins_default = pinctrl_lookup_state(i2c_imx->pinctrl,
+			PINCTRL_STATE_DEFAULT);
+	i2c_imx->pinctrl_pins_gpio = pinctrl_lookup_state(i2c_imx->pinctrl,
+			"gpio");
+	rinfo->sda_gpio = of_get_named_gpio_flags(pdev->dev.of_node,
+			"sda-gpios", 0, NULL);
+	rinfo->scl_gpio = of_get_named_gpio_flags(pdev->dev.of_node,
+			"scl-gpios", 0, NULL);
+
+	if (!gpio_is_valid(rinfo->sda_gpio) ||
+	    !gpio_is_valid(rinfo->scl_gpio) ||
+	    IS_ERR(i2c_imx->pinctrl_pins_default) ||
+	    IS_ERR(i2c_imx->pinctrl_pins_gpio)) {
+		dev_dbg(&pdev->dev, "recovery information incomplete\n");
+		return;
+	}
+
+	dev_dbg(&pdev->dev, "using scl-gpio %d and sda-gpio %d for recovery\n",
+			rinfo->sda_gpio, rinfo->scl_gpio);
+
+	rinfo->prepare_recovery = i2c_imx_prepare_recovery;
+	rinfo->unprepare_recovery = i2c_imx_unprepare_recovery;
+	rinfo->recover_bus = i2c_generic_gpio_recovery;
+	i2c_imx->adapter.bus_recovery_info = rinfo;
+}
+
 static u32 i2c_imx_func(struct i2c_adapter *adapter)
 {
 	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL
@@ -1023,6 +1085,13 @@ static int i2c_imx_probe(struct platform_device *pdev)
 		dev_err(&pdev->dev, "can't enable I2C clock\n");
 		return ret;
 	}
+
+	i2c_imx->pinctrl = devm_pinctrl_get(&pdev->dev);
+	if (IS_ERR(i2c_imx->pinctrl)) {
+		ret = PTR_ERR(i2c_imx->pinctrl);
+		goto clk_disable;
+	}
+
 	/* Request IRQ */
 	ret = devm_request_irq(&pdev->dev, irq, i2c_imx_isr, 0,
 				pdev->name, i2c_imx);
@@ -1056,6 +1125,8 @@ static int i2c_imx_probe(struct platform_device *pdev)
 		goto clk_disable;
 	}
 
+	i2c_imx_init_recovery_info(i2c_imx, pdev);
+
 	/* Set up platform driver data */
 	platform_set_drvdata(pdev, i2c_imx);
 	clk_disable_unprepare(i2c_imx->clk);

drivers/i2c/busses/i2c-ismt.c

@@ -165,14 +165,13 @@ struct ismt_desc {
 
 struct ismt_priv {
 	struct i2c_adapter adapter;
-	void *smba;				/* PCI BAR */
+	void __iomem *smba;			/* PCI BAR */
 	struct pci_dev *pci_dev;
 	struct ismt_desc *hw;			/* descriptor virt base addr */
 	dma_addr_t io_rng_dma;			/* descriptor HW base addr */
 	u8 head;				/* ring buffer head pointer */
 	struct completion cmp;			/* interrupt completion */
 	u8 dma_buffer[I2C_SMBUS_BLOCK_MAX + 1];	/* temp R/W data buffer */
-	bool using_msi;				/* type of interrupt flag */
 };
 
 /**
@@ -398,7 +397,7 @@ static int ismt_access(struct i2c_adapter *adap, u16 addr,
 	desc->tgtaddr_rw = ISMT_DESC_ADDR_RW(addr, read_write);
 
 	/* Initialize common control bits */
-	if (likely(priv->using_msi))
+	if (likely(pci_dev_msi_enabled(priv->pci_dev)))
 		desc->control = ISMT_DESC_INT | ISMT_DESC_FAIR;
 	else
 		desc->control = ISMT_DESC_FAIR;
@@ -789,11 +788,8 @@ static int ismt_int_init(struct ismt_priv *priv)
 
 	/* Try using MSI interrupts */
 	err = pci_enable_msi(priv->pci_dev);
-	if (err) {
-		dev_warn(&priv->pci_dev->dev,
-			 "Unable to use MSI interrupts, falling back to legacy\n");
+	if (err)
 		goto intx;
-	}
 
 	err = devm_request_irq(&priv->pci_dev->dev,
 			       priv->pci_dev->irq,
@@ -806,11 +802,13 @@ static int ismt_int_init(struct ismt_priv *priv)
 		goto intx;
 	}
 
-	priv->using_msi = true;
-	goto done;
+	return 0;
 
 	/* Try using legacy interrupts */
 intx:
+	dev_warn(&priv->pci_dev->dev,
+		 "Unable to use MSI interrupts, falling back to legacy\n");
+
 	err = devm_request_irq(&priv->pci_dev->dev,
 			       priv->pci_dev->irq,
 			       ismt_do_interrupt,
@@ -819,12 +817,9 @@ intx:
 			       priv);
 	if (err) {
 		dev_err(&priv->pci_dev->dev, "no usable interrupts\n");
-		return -ENODEV;
+		return err;
 	}
 
-	priv->using_msi = false;
-
-done:
 	return 0;
 }
 
@@ -847,17 +842,13 @@ ismt_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 		return -ENOMEM;
 
 	pci_set_drvdata(pdev, priv);
+
 	i2c_set_adapdata(&priv->adapter, priv);
 	priv->adapter.owner = THIS_MODULE;
-
 	priv->adapter.class = I2C_CLASS_HWMON;
-
 	priv->adapter.algo = &smbus_algorithm;
-
-	/* set up the sysfs linkage to our parent device */
 	priv->adapter.dev.parent = &pdev->dev;
-
-	/* number of retries on lost arbitration */
+	ACPI_COMPANION_SET(&priv->adapter.dev, ACPI_COMPANION(&pdev->dev));
 	priv->adapter.retries = ISMT_MAX_RETRIES;
 
 	priv->pci_dev = pdev;
@@ -904,8 +895,7 @@ ismt_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	priv->smba = pcim_iomap(pdev, SMBBAR, len);
 	if (!priv->smba) {
 		dev_err(&pdev->dev, "Unable to ioremap SMBus BAR\n");
-		err = -ENODEV;
-		goto fail;
+		return -ENODEV;
 	}
 
 	if ((pci_set_dma_mask(pdev, DMA_BIT_MASK(64)) != 0) ||
@@ -915,32 +905,26 @@ ismt_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 						 DMA_BIT_MASK(32)) != 0)) {
 			dev_err(&pdev->dev, "pci_set_dma_mask fail %p\n",
 				pdev);
-			err = -ENODEV;
-			goto fail;
+			return -ENODEV;
 		}
 	}
 
 	err = ismt_dev_init(priv);
 	if (err)
-		goto fail;
+		return err;
 
 	ismt_hw_init(priv);
 
 	err = ismt_int_init(priv);
 	if (err)
-		goto fail;
+		return err;
 
 	err = i2c_add_adapter(&priv->adapter);
 	if (err) {
 		dev_err(&pdev->dev, "Failed to add SMBus iSMT adapter\n");
-		err = -ENODEV;
-		goto fail;
+		return -ENODEV;
 	}
 	return 0;
-
-fail:
-	pci_release_region(pdev, SMBBAR);
-	return err;
 }
 
 /**
@@ -952,47 +936,13 @@ static void ismt_remove(struct pci_dev *pdev)
 	struct ismt_priv *priv = pci_get_drvdata(pdev);
 
 	i2c_del_adapter(&priv->adapter);
-	pci_release_region(pdev, SMBBAR);
 }
 
-/**
- * ismt_suspend() - place the device in suspend
- * @pdev: PCI-Express device
- * @mesg: PM message
- */
-#ifdef CONFIG_PM
-static int ismt_suspend(struct pci_dev *pdev, pm_message_t mesg)
-{
-	pci_save_state(pdev);
-	pci_set_power_state(pdev, pci_choose_state(pdev, mesg));
-	return 0;
-}
-
-/**
- * ismt_resume() - PCI resume code
- * @pdev: PCI-Express device
- */
-static int ismt_resume(struct pci_dev *pdev)
-{
-	pci_set_power_state(pdev, PCI_D0);
-	pci_restore_state(pdev);
-	return pci_enable_device(pdev);
-}
-
-#else
-
-#define ismt_suspend NULL
-#define ismt_resume NULL
-
-#endif
-
 static struct pci_driver ismt_driver = {
 	.name = "ismt_smbus",
 	.id_table = ismt_ids,
 	.probe = ismt_probe,
 	.remove = ismt_remove,
-	.suspend = ismt_suspend,
-	.resume = ismt_resume,
 };
 
 module_pci_driver(ismt_driver);

drivers/i2c/busses/i2c-meson.c

@@ -475,6 +475,7 @@ static const struct of_device_id meson_i2c_match[] = {
 	{ .compatible = "amlogic,meson6-i2c" },
 	{ },
 };
+MODULE_DEVICE_TABLE(of, meson_i2c_match);
 
 static struct platform_driver meson_i2c_driver = {
 	.probe   = meson_i2c_probe,

drivers/i2c/busses/i2c-mt65xx.c

@@ -728,11 +728,27 @@ static int mtk_i2c_remove(struct platform_device *pdev)
 	return 0;
 }
 
+#ifdef CONFIG_PM_SLEEP
+static int mtk_i2c_resume(struct device *dev)
+{
+	struct mtk_i2c *i2c = dev_get_drvdata(dev);
+
+	mtk_i2c_init_hw(i2c);
+
+	return 0;
+}
+#endif
+
+static const struct dev_pm_ops mtk_i2c_pm = {
+	SET_SYSTEM_SLEEP_PM_OPS(NULL, mtk_i2c_resume)
+};
+
 static struct platform_driver mtk_i2c_driver = {
 	.probe = mtk_i2c_probe,
 	.remove = mtk_i2c_remove,
 	.driver = {
 		.name = I2C_DRV_NAME,
+		.pm = &mtk_i2c_pm,
 		.of_match_table = of_match_ptr(mtk_i2c_of_match),
 	},
 };

drivers/i2c/busses/i2c-ocores.c

@@ -92,6 +92,16 @@ static void oc_setreg_32(struct ocores_i2c *i2c, int reg, u8 value)
 	iowrite32(value, i2c->base + (reg << i2c->reg_shift));
 }
 
+static void oc_setreg_16be(struct ocores_i2c *i2c, int reg, u8 value)
+{
+	iowrite16be(value, i2c->base + (reg << i2c->reg_shift));
+}
+
+static void oc_setreg_32be(struct ocores_i2c *i2c, int reg, u8 value)
+{
+	iowrite32be(value, i2c->base + (reg << i2c->reg_shift));
+}
+
 static inline u8 oc_getreg_8(struct ocores_i2c *i2c, int reg)
 {
 	return ioread8(i2c->base + (reg << i2c->reg_shift));
@@ -107,6 +117,16 @@ static inline u8 oc_getreg_32(struct ocores_i2c *i2c, int reg)
 	return ioread32(i2c->base + (reg << i2c->reg_shift));
 }
 
+static inline u8 oc_getreg_16be(struct ocores_i2c *i2c, int reg)
+{
+	return ioread16be(i2c->base + (reg << i2c->reg_shift));
+}
+
+static inline u8 oc_getreg_32be(struct ocores_i2c *i2c, int reg)
+{
+	return ioread32be(i2c->base + (reg << i2c->reg_shift));
+}
+
 static inline void oc_setreg(struct ocores_i2c *i2c, int reg, u8 value)
 {
 	i2c->setreg(i2c, reg, value);
@@ -428,6 +448,9 @@ static int ocores_i2c_probe(struct platform_device *pdev)
 		i2c->reg_io_width = 1; /* Set to default value */
 
 	if (!i2c->setreg || !i2c->getreg) {
+		bool be = pdata ? pdata->big_endian :
+			of_device_is_big_endian(pdev->dev.of_node);
+
 		switch (i2c->reg_io_width) {
 		case 1:
 			i2c->setreg = oc_setreg_8;
@@ -435,13 +458,13 @@ static int ocores_i2c_probe(struct platform_device *pdev)
 			break;
 
 		case 2:
-			i2c->setreg = oc_setreg_16;
-			i2c->getreg = oc_getreg_16;
+			i2c->setreg = be ? oc_setreg_16be : oc_setreg_16;
+			i2c->getreg = be ? oc_getreg_16be : oc_getreg_16;
 			break;
 
 		case 4:
-			i2c->setreg = oc_setreg_32;
-			i2c->getreg = oc_getreg_32;
+			i2c->setreg = be ? oc_setreg_32be : oc_setreg_32;
+			i2c->getreg = be ? oc_getreg_32be : oc_getreg_32;
 			break;
 
 		default:

drivers/i2c/busses/i2c-pnx.c

@@ -496,7 +496,7 @@ i2c_pnx_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
 	struct i2c_msg *pmsg;
 	int rc = 0, completed = 0, i;
 	struct i2c_pnx_algo_data *alg_data = adap->algo_data;
-	u32 stat = ioread32(I2C_REG_STS(alg_data));
+	u32 stat;
 
 	dev_dbg(&alg_data->adapter.dev,
 		"%s(): entering: %d messages, stat = %04x.\n",
@@ -659,9 +659,8 @@ static int i2c_pnx_probe(struct platform_device *pdev)
 	if (IS_ERR(alg_data->clk))
 		return PTR_ERR(alg_data->clk);
 
-	init_timer(&alg_data->mif.timer);
-	alg_data->mif.timer.function = i2c_pnx_timeout;
-	alg_data->mif.timer.data = (unsigned long)alg_data;
+	setup_timer(&alg_data->mif.timer, i2c_pnx_timeout,
+			(unsigned long)alg_data);
 
 	snprintf(alg_data->adapter.name, sizeof(alg_data->adapter.name),
 		 "%s", pdev->name);

drivers/i2c/busses/i2c-pxa.c

@@ -46,12 +46,15 @@ struct pxa_reg_layout {
 	u32 icr;
 	u32 isr;
 	u32 isar;
+	u32 ilcr;
+	u32 iwcr;
 };
 
 enum pxa_i2c_types {
 	REGS_PXA2XX,
 	REGS_PXA3XX,
 	REGS_CE4100,
+	REGS_PXA910,
 };
 
 /*
@@ -79,12 +82,22 @@ static struct pxa_reg_layout pxa_reg_layout[] = {
 		.isr =	0x04,
 		/* no isar register */
 	},
+	[REGS_PXA910] = {
+		.ibmr = 0x00,
+		.idbr = 0x08,
+		.icr =	0x10,
+		.isr =	0x18,
+		.isar = 0x20,
+		.ilcr = 0x28,
+		.iwcr = 0x30,
+	},
 };
 
 static const struct platform_device_id i2c_pxa_id_table[] = {
 	{ "pxa2xx-i2c",		REGS_PXA2XX },
 	{ "pxa3xx-pwri2c",	REGS_PXA3XX },
 	{ "ce4100-i2c",		REGS_CE4100 },
+	{ "pxa910-i2c",		REGS_PXA910 },
 	{ },
 };
 MODULE_DEVICE_TABLE(platform, i2c_pxa_id_table);
@@ -124,6 +137,23 @@ MODULE_DEVICE_TABLE(platform, i2c_pxa_id_table);
 #define ISR_SAD		(1 << 9)	   /* slave address detected */
 #define ISR_BED		(1 << 10)	   /* bus error no ACK/NAK */
 
+/* bit field shift & mask */
+#define ILCR_SLV_SHIFT		0
+#define ILCR_SLV_MASK		(0x1FF << ILCR_SLV_SHIFT)
+#define ILCR_FLV_SHIFT		9
+#define ILCR_FLV_MASK		(0x1FF << ILCR_FLV_SHIFT)
+#define ILCR_HLVL_SHIFT		18
+#define ILCR_HLVL_MASK		(0x1FF << ILCR_HLVL_SHIFT)
+#define ILCR_HLVH_SHIFT		27
+#define ILCR_HLVH_MASK		(0x1F << ILCR_HLVH_SHIFT)
+
+#define IWCR_CNT_SHIFT		0
+#define IWCR_CNT_MASK		(0x1F << IWCR_CNT_SHIFT)
+#define IWCR_HS_CNT1_SHIFT	5
+#define IWCR_HS_CNT1_MASK	(0x1F << IWCR_HS_CNT1_SHIFT)
+#define IWCR_HS_CNT2_SHIFT	10
+#define IWCR_HS_CNT2_MASK	(0x1F << IWCR_HS_CNT2_SHIFT)
+
 struct pxa_i2c {
 	spinlock_t		lock;
 	wait_queue_head_t	wait;
@@ -150,6 +180,8 @@ struct pxa_i2c {
 	void __iomem		*reg_icr;
 	void __iomem		*reg_isr;
 	void __iomem		*reg_isar;
+	void __iomem		*reg_ilcr;
+	void __iomem		*reg_iwcr;
 
 	unsigned long		iobase;
 	unsigned long		iosize;
@@ -168,6 +200,8 @@ struct pxa_i2c {
 #define _ICR(i2c)	((i2c)->reg_icr)
 #define _ISR(i2c)	((i2c)->reg_isr)
 #define _ISAR(i2c)	((i2c)->reg_isar)
+#define _ILCR(i2c)	((i2c)->reg_ilcr)
+#define _IWCR(i2c)	((i2c)->reg_iwcr)
 
 /*
  * I2C Slave mode address
@@ -1102,7 +1136,7 @@ static const struct i2c_algorithm i2c_pxa_pio_algorithm = {
 static const struct of_device_id i2c_pxa_dt_ids[] = {
 	{ .compatible = "mrvl,pxa-i2c", .data = (void *)REGS_PXA2XX },
 	{ .compatible = "mrvl,pwri2c", .data = (void *)REGS_PXA3XX },
-	{ .compatible = "mrvl,mmp-twsi", .data = (void *)REGS_PXA2XX },
+	{ .compatible = "mrvl,mmp-twsi", .data = (void *)REGS_PXA910 },
 	{}
 };
 MODULE_DEVICE_TABLE(of, i2c_pxa_dt_ids);
@@ -1203,6 +1237,11 @@ static int i2c_pxa_probe(struct platform_device *dev)
 	if (i2c_type != REGS_CE4100)
 		i2c->reg_isar = i2c->reg_base + pxa_reg_layout[i2c_type].isar;
 
+	if (i2c_type == REGS_PXA910) {
+		i2c->reg_ilcr = i2c->reg_base + pxa_reg_layout[i2c_type].ilcr;
+		i2c->reg_iwcr = i2c->reg_base + pxa_reg_layout[i2c_type].iwcr;
+	}
+
 	i2c->iobase = res->start;
 	i2c->iosize = resource_size(res);
 

drivers/i2c/busses/i2c-rcar.c

@@ -27,7 +27,6 @@
 #include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/i2c.h>
-#include <linux/i2c/i2c-rcar.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/of_device.h>
@@ -103,6 +102,7 @@
 enum rcar_i2c_type {
 	I2C_RCAR_GEN1,
 	I2C_RCAR_GEN2,
+	I2C_RCAR_GEN3,
 };
 
 struct rcar_i2c_priv {
@@ -178,6 +178,7 @@ static int rcar_i2c_clock_calculate(struct rcar_i2c_priv *priv,
 		cdf_width = 2;
 		break;
 	case I2C_RCAR_GEN2:
+	case I2C_RCAR_GEN3:
 		cdf_width = 3;
 		break;
 	default:
@@ -625,13 +626,13 @@ static const struct of_device_id rcar_i2c_dt_ids[] = {
 	{ .compatible = "renesas,i2c-r8a7792", .data = (void *)I2C_RCAR_GEN2 },
 	{ .compatible = "renesas,i2c-r8a7793", .data = (void *)I2C_RCAR_GEN2 },
 	{ .compatible = "renesas,i2c-r8a7794", .data = (void *)I2C_RCAR_GEN2 },
+	{ .compatible = "renesas,i2c-r8a7795", .data = (void *)I2C_RCAR_GEN3 },
 	{},
 };
 MODULE_DEVICE_TABLE(of, rcar_i2c_dt_ids);
 
 static int rcar_i2c_probe(struct platform_device *pdev)
 {
-	struct i2c_rcar_platform_data *pdata = dev_get_platdata(&pdev->dev);
 	struct rcar_i2c_priv *priv;
 	struct i2c_adapter *adap;
 	struct resource *res;
@@ -650,15 +651,9 @@ static int rcar_i2c_probe(struct platform_device *pdev)
 	}
 
 	bus_speed = 100000; /* default 100 kHz */
-	ret = of_property_read_u32(dev->of_node, "clock-frequency", &bus_speed);
-	if (ret < 0 && pdata && pdata->bus_speed)
-		bus_speed = pdata->bus_speed;
+	of_property_read_u32(dev->of_node, "clock-frequency", &bus_speed);
 
-	if (pdev->dev.of_node)
-		priv->devtype = (long)of_match_device(rcar_i2c_dt_ids,
-						      dev)->data;
-	else
-		priv->devtype = platform_get_device_id(pdev)->driver_data;
+	priv->devtype = (enum rcar_i2c_type)of_match_device(rcar_i2c_dt_ids, dev)->data;
 
 	ret = rcar_i2c_clock_calculate(priv, bus_speed, dev);
 	if (ret < 0)
@@ -716,14 +711,6 @@ static int rcar_i2c_remove(struct platform_device *pdev)
 	return 0;
 }
 
-static const struct platform_device_id rcar_i2c_id_table[] = {
-	{ "i2c-rcar",		I2C_RCAR_GEN1 },
-	{ "i2c-rcar_gen1",	I2C_RCAR_GEN1 },
-	{ "i2c-rcar_gen2",	I2C_RCAR_GEN2 },
-	{},
-};
-MODULE_DEVICE_TABLE(platform, rcar_i2c_id_table);
-
 static struct platform_driver rcar_i2c_driver = {
 	.driver	= {
 		.name	= "i2c-rcar",
@@ -731,7 +718,6 @@ static struct platform_driver rcar_i2c_driver = {
 	},
 	.probe		= rcar_i2c_probe,
 	.remove		= rcar_i2c_remove,
-	.id_table	= rcar_i2c_id_table,
 };
 
 module_platform_driver(rcar_i2c_driver);

drivers/i2c/busses/i2c-rk3x.c

@@ -858,6 +858,7 @@ static const struct of_device_id rk3x_i2c_match[] = {
 	{ .compatible = "rockchip,rk3288-i2c", .data = (void *)&soc_data[2] },
 	{},
 };
+MODULE_DEVICE_TABLE(of, rk3x_i2c_match);
 
 static int rk3x_i2c_probe(struct platform_device *pdev)
 {

drivers/i2c/busses/i2c-sh_mobile.c

@@ -836,6 +836,7 @@ static const struct of_device_id sh_mobile_i2c_dt_ids[] = {
 	{ .compatible = "renesas,iic-r8a7792", .data = &fast_clock_dt_config },
 	{ .compatible = "renesas,iic-r8a7793", .data = &fast_clock_dt_config },
 	{ .compatible = "renesas,iic-r8a7794", .data = &fast_clock_dt_config },
+	{ .compatible = "renesas,iic-r8a7795", .data = &fast_clock_dt_config },
 	{ .compatible = "renesas,iic-sh73a0", .data = &fast_clock_dt_config },
 	{},
 };

drivers/i2c/busses/i2c-sirf.c

@@ -358,11 +358,29 @@ static int i2c_sirfsoc_probe(struct platform_device *pdev)
 	if (err < 0)
 		bitrate = SIRFSOC_I2C_DEFAULT_SPEED;
 
-	if (bitrate < 100000)
-		regval =
-			(2 * ctrl_speed) / (bitrate * 11);
-	else
+	/*
+	 * Due to some hardware design issues, we need to tune the formula.
+	 * Since i2c is open drain interface that allows the slave to
+	 * stall the transaction by holding the SCL line at '0', the RTL
+	 * implementation is waiting for SCL feedback from the pin after
+	 * setting it to High-Z ('1'). This wait adds to the high-time
+	 * interval counter few cycles of the input synchronization
+	 * (depending on the SCL_FILTER_REG field), and also the time it
+	 * takes for the board pull-up resistor to rise the SCL line.
+	 * For slow SCL settings these additions are negligible,
+	 * but they start to affect the speed when clock is set to faster
+	 * frequencies.
+	 * Through the actual tests, use the different user_div value(which
+	 * in the divider formular 'Fio / (Fi2c * user_div)') to adapt
+	 * the different ranges of i2c bus clock frequency, to make the SCL
+	 * more accurate.
+	 */
+	if (bitrate <= 30000)
 		regval = ctrl_speed / (bitrate * 5);
+	else if (bitrate > 30000 && bitrate <= 280000)
+		regval = (2 * ctrl_speed) / (bitrate * 11);
+	else
+		regval = ctrl_speed / (bitrate * 6);
 
 	writel(regval, siic->base + SIRFSOC_I2C_CLK_CTRL);
 	if (regval > 0xFF)

drivers/i2c/busses/i2c-stu300.c

@@ -977,6 +977,7 @@ static const struct of_device_id stu300_dt_match[] = {
 	{ .compatible = "st,ddci2c" },
 	{},
 };
+MODULE_DEVICE_TABLE(of, stu300_dt_match);
 
 static struct platform_driver stu300_i2c_driver = {
 	.driver = {

drivers/i2c/busses/i2c-tegra.c

@@ -873,7 +873,6 @@ static int tegra_i2c_probe(struct platform_device *pdev)
 	i2c_dev->adapter.class = I2C_CLASS_DEPRECATED;
 	strlcpy(i2c_dev->adapter.name, "Tegra I2C adapter",
 		sizeof(i2c_dev->adapter.name));
-	i2c_dev->adapter.algo = &tegra_i2c_algo;
 	i2c_dev->adapter.dev.parent = &pdev->dev;
 	i2c_dev->adapter.nr = pdev->id;
 	i2c_dev->adapter.dev.of_node = pdev->dev.of_node;

drivers/i2c/busses/i2c-uniphier-f.c

@@ -0,0 +1,584 @@
+/*
+ * Copyright (C) 2015 Masahiro Yamada <yamada.masahiro@socionext.com>
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/clk.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+#define UNIPHIER_FI2C_CR	0x00	/* control register */
+#define     UNIPHIER_FI2C_CR_MST	BIT(3)	/* master mode */
+#define     UNIPHIER_FI2C_CR_STA	BIT(2)	/* start condition */
+#define     UNIPHIER_FI2C_CR_STO	BIT(1)	/* stop condition */
+#define     UNIPHIER_FI2C_CR_NACK	BIT(0)	/* do not return ACK */
+#define UNIPHIER_FI2C_DTTX	0x04	/* TX FIFO */
+#define     UNIPHIER_FI2C_DTTX_CMD	BIT(8)	/* send command (slave addr) */
+#define     UNIPHIER_FI2C_DTTX_RD	BIT(0)	/* read transaction */
+#define UNIPHIER_FI2C_DTRX	0x04	/* RX FIFO */
+#define UNIPHIER_FI2C_SLAD	0x0c	/* slave address */
+#define UNIPHIER_FI2C_CYC	0x10	/* clock cycle control */
+#define UNIPHIER_FI2C_LCTL	0x14	/* clock low period control */
+#define UNIPHIER_FI2C_SSUT	0x18	/* restart/stop setup time control */
+#define UNIPHIER_FI2C_DSUT	0x1c	/* data setup time control */
+#define UNIPHIER_FI2C_INT	0x20	/* interrupt status */
+#define UNIPHIER_FI2C_IE	0x24	/* interrupt enable */
+#define UNIPHIER_FI2C_IC	0x28	/* interrupt clear */
+#define     UNIPHIER_FI2C_INT_TE	BIT(9)	/* TX FIFO empty */
+#define     UNIPHIER_FI2C_INT_RF	BIT(8)	/* RX FIFO full */
+#define     UNIPHIER_FI2C_INT_TC	BIT(7)	/* send complete (STOP) */
+#define     UNIPHIER_FI2C_INT_RC	BIT(6)	/* receive complete (STOP) */
+#define     UNIPHIER_FI2C_INT_TB	BIT(5)	/* sent specified bytes */
+#define     UNIPHIER_FI2C_INT_RB	BIT(4)	/* received specified bytes */
+#define     UNIPHIER_FI2C_INT_NA	BIT(2)	/* no ACK */
+#define     UNIPHIER_FI2C_INT_AL	BIT(1)	/* arbitration lost */
+#define UNIPHIER_FI2C_SR	0x2c	/* status register */
+#define     UNIPHIER_FI2C_SR_DB		BIT(12)	/* device busy */
+#define     UNIPHIER_FI2C_SR_STS	BIT(11)	/* stop condition detected */
+#define     UNIPHIER_FI2C_SR_BB		BIT(8)	/* bus busy */
+#define     UNIPHIER_FI2C_SR_RFF	BIT(3)	/* RX FIFO full */
+#define     UNIPHIER_FI2C_SR_RNE	BIT(2)	/* RX FIFO not empty */
+#define     UNIPHIER_FI2C_SR_TNF	BIT(1)	/* TX FIFO not full */
+#define     UNIPHIER_FI2C_SR_TFE	BIT(0)	/* TX FIFO empty */
+#define UNIPHIER_FI2C_RST	0x34	/* reset control */
+#define     UNIPHIER_FI2C_RST_TBRST	BIT(2)	/* clear TX FIFO */
+#define     UNIPHIER_FI2C_RST_RBRST	BIT(1)	/* clear RX FIFO */
+#define     UNIPHIER_FI2C_RST_RST	BIT(0)	/* forcible bus reset */
+#define UNIPHIER_FI2C_BM	0x38	/* bus monitor */
+#define     UNIPHIER_FI2C_BM_SDAO	BIT(3)	/* output for SDA line */
+#define     UNIPHIER_FI2C_BM_SDAS	BIT(2)	/* readback of SDA line */
+#define     UNIPHIER_FI2C_BM_SCLO	BIT(1)	/* output for SCL line */
+#define     UNIPHIER_FI2C_BM_SCLS	BIT(0)	/* readback of SCL line */
+#define UNIPHIER_FI2C_NOISE	0x3c	/* noise filter control */
+#define UNIPHIER_FI2C_TBC	0x40	/* TX byte count setting */
+#define UNIPHIER_FI2C_RBC	0x44	/* RX byte count setting */
+#define UNIPHIER_FI2C_TBCM	0x48	/* TX byte count monitor */
+#define UNIPHIER_FI2C_RBCM	0x4c	/* RX byte count monitor */
+#define UNIPHIER_FI2C_BRST	0x50	/* bus reset */
+#define     UNIPHIER_FI2C_BRST_FOEN	BIT(1)	/* normal operation */
+#define     UNIPHIER_FI2C_BRST_RSCL	BIT(0)	/* release SCL */
+
+#define UNIPHIER_FI2C_INT_FAULTS	\
+				(UNIPHIER_FI2C_INT_NA | UNIPHIER_FI2C_INT_AL)
+#define UNIPHIER_FI2C_INT_STOP		\
+				(UNIPHIER_FI2C_INT_TC | UNIPHIER_FI2C_INT_RC)
+
+#define UNIPHIER_FI2C_RD		BIT(0)
+#define UNIPHIER_FI2C_STOP		BIT(1)
+#define UNIPHIER_FI2C_MANUAL_NACK	BIT(2)
+#define UNIPHIER_FI2C_BYTE_WISE		BIT(3)
+#define UNIPHIER_FI2C_DEFER_STOP_COMP	BIT(4)
+
+#define UNIPHIER_FI2C_DEFAULT_SPEED	100000
+#define UNIPHIER_FI2C_MAX_SPEED		400000
+#define UNIPHIER_FI2C_FIFO_SIZE		8
+
+struct uniphier_fi2c_priv {
+	struct completion comp;
+	struct i2c_adapter adap;
+	void __iomem *membase;
+	struct clk *clk;
+	unsigned int len;
+	u8 *buf;
+	u32 enabled_irqs;
+	int error;
+	unsigned int flags;
+	unsigned int busy_cnt;
+};
+
+static void uniphier_fi2c_fill_txfifo(struct uniphier_fi2c_priv *priv,
+				      bool first)
+{
+	int fifo_space = UNIPHIER_FI2C_FIFO_SIZE;
+
+	/*
+	 * TX-FIFO stores slave address in it for the first access.
+	 * Decrement the counter.
+	 */
+	if (first)
+		fifo_space--;
+
+	while (priv->len) {
+		if (fifo_space-- <= 0)
+			break;
+
+		dev_dbg(&priv->adap.dev, "write data: %02x\n", *priv->buf);
+		writel(*priv->buf++, priv->membase + UNIPHIER_FI2C_DTTX);
+		priv->len--;
+	}
+}
+
+static void uniphier_fi2c_drain_rxfifo(struct uniphier_fi2c_priv *priv)
+{
+	int fifo_left = priv->flags & UNIPHIER_FI2C_BYTE_WISE ?
+						1 : UNIPHIER_FI2C_FIFO_SIZE;
+
+	while (priv->len) {
+		if (fifo_left-- <= 0)
+			break;
+
+		*priv->buf++ = readl(priv->membase + UNIPHIER_FI2C_DTRX);
+		dev_dbg(&priv->adap.dev, "read data: %02x\n", priv->buf[-1]);
+		priv->len--;
+	}
+}
+
+static void uniphier_fi2c_set_irqs(struct uniphier_fi2c_priv *priv)
+{
+	writel(priv->enabled_irqs, priv->membase + UNIPHIER_FI2C_IE);
+}
+
+static void uniphier_fi2c_clear_irqs(struct uniphier_fi2c_priv *priv)
+{
+	writel(-1, priv->membase + UNIPHIER_FI2C_IC);
+}
+
+static void uniphier_fi2c_stop(struct uniphier_fi2c_priv *priv)
+{
+	dev_dbg(&priv->adap.dev, "stop condition\n");
+
+	priv->enabled_irqs |= UNIPHIER_FI2C_INT_STOP;
+	uniphier_fi2c_set_irqs(priv);
+	writel(UNIPHIER_FI2C_CR_MST | UNIPHIER_FI2C_CR_STO,
+	       priv->membase + UNIPHIER_FI2C_CR);
+}
+
+static irqreturn_t uniphier_fi2c_interrupt(int irq, void *dev_id)
+{
+	struct uniphier_fi2c_priv *priv = dev_id;
+	u32 irq_status;
+
+	irq_status = readl(priv->membase + UNIPHIER_FI2C_INT);
+
+	dev_dbg(&priv->adap.dev,
+		"interrupt: enabled_irqs=%04x, irq_status=%04x\n",
+		priv->enabled_irqs, irq_status);
+
+	if (irq_status & UNIPHIER_FI2C_INT_STOP)
+		goto complete;
+
+	if (unlikely(irq_status & UNIPHIER_FI2C_INT_AL)) {
+		dev_dbg(&priv->adap.dev, "arbitration lost\n");
+		priv->error = -EAGAIN;
+		goto complete;
+	}
+
+	if (unlikely(irq_status & UNIPHIER_FI2C_INT_NA)) {
+		dev_dbg(&priv->adap.dev, "could not get ACK\n");
+		priv->error = -ENXIO;
+		if (priv->flags & UNIPHIER_FI2C_RD) {
+			/*
+			 * work around a hardware bug:
+			 * The receive-completed interrupt is never set even if
+			 * STOP condition is detected after the address phase
+			 * of read transaction fails to get ACK.
+			 * To avoid time-out error, we issue STOP here,
+			 * but do not wait for its completion.
+			 * It should be checked after exiting this handler.
+			 */
+			uniphier_fi2c_stop(priv);
+			priv->flags |= UNIPHIER_FI2C_DEFER_STOP_COMP;
+			goto complete;
+		}
+		goto stop;
+	}
+
+	if (irq_status & UNIPHIER_FI2C_INT_TE) {
+		if (!priv->len)
+			goto data_done;
+
+		uniphier_fi2c_fill_txfifo(priv, false);
+		goto handled;
+	}
+
+	if (irq_status & (UNIPHIER_FI2C_INT_RF | UNIPHIER_FI2C_INT_RB)) {
+		uniphier_fi2c_drain_rxfifo(priv);
+		if (!priv->len)
+			goto data_done;
+
+		if (unlikely(priv->flags & UNIPHIER_FI2C_MANUAL_NACK)) {
+			if (priv->len <= UNIPHIER_FI2C_FIFO_SIZE &&
+			    !(priv->flags & UNIPHIER_FI2C_BYTE_WISE)) {
+				dev_dbg(&priv->adap.dev,
+					"enable read byte count IRQ\n");
+				priv->enabled_irqs |= UNIPHIER_FI2C_INT_RB;
+				uniphier_fi2c_set_irqs(priv);
+				priv->flags |= UNIPHIER_FI2C_BYTE_WISE;
+			}
+			if (priv->len <= 1) {
+				dev_dbg(&priv->adap.dev, "set NACK\n");
+				writel(UNIPHIER_FI2C_CR_MST |
+				       UNIPHIER_FI2C_CR_NACK,
+				       priv->membase + UNIPHIER_FI2C_CR);
+			}
+		}
+
+		goto handled;
+	}
+
+	return IRQ_NONE;
+
+data_done:
+	if (priv->flags & UNIPHIER_FI2C_STOP) {
+stop:
+		uniphier_fi2c_stop(priv);
+	} else {
+complete:
+		priv->enabled_irqs = 0;
+		uniphier_fi2c_set_irqs(priv);
+		complete(&priv->comp);
+	}
+
+handled:
+	uniphier_fi2c_clear_irqs(priv);
+
+	return IRQ_HANDLED;
+}
+
+static void uniphier_fi2c_tx_init(struct uniphier_fi2c_priv *priv, u16 addr)
+{
+	priv->enabled_irqs |= UNIPHIER_FI2C_INT_TE;
+	/* do not use TX byte counter */
+	writel(0, priv->membase + UNIPHIER_FI2C_TBC);
+	/* set slave address */
+	writel(UNIPHIER_FI2C_DTTX_CMD | addr << 1,
+	       priv->membase + UNIPHIER_FI2C_DTTX);
+	/* first chunk of data */
+	uniphier_fi2c_fill_txfifo(priv, true);
+}
+
+static void uniphier_fi2c_rx_init(struct uniphier_fi2c_priv *priv, u16 addr)
+{
+	priv->flags |= UNIPHIER_FI2C_RD;
+
+	if (likely(priv->len < 256)) {
+		/*
+		 * If possible, use RX byte counter.
+		 * It can automatically handle NACK for the last byte.
+		 */
+		writel(priv->len, priv->membase + UNIPHIER_FI2C_RBC);
+		priv->enabled_irqs |= UNIPHIER_FI2C_INT_RF |
+				      UNIPHIER_FI2C_INT_RB;
+	} else {
+		/*
+		 * The byte counter can not count over 256.  In this case,
+		 * do not use it at all.  Drain data when FIFO gets full,
+		 * but treat the last portion as a special case.
+		 */
+		writel(0, priv->membase + UNIPHIER_FI2C_RBC);
+		priv->flags |= UNIPHIER_FI2C_MANUAL_NACK;
+		priv->enabled_irqs |= UNIPHIER_FI2C_INT_RF;
+	}
+
+	/* set slave address with RD bit */
+	writel(UNIPHIER_FI2C_DTTX_CMD | UNIPHIER_FI2C_DTTX_RD | addr << 1,
+	       priv->membase + UNIPHIER_FI2C_DTTX);
+}
+
+static void uniphier_fi2c_reset(struct uniphier_fi2c_priv *priv)
+{
+	writel(UNIPHIER_FI2C_RST_RST, priv->membase + UNIPHIER_FI2C_RST);
+}
+
+static void uniphier_fi2c_prepare_operation(struct uniphier_fi2c_priv *priv)
+{
+	writel(UNIPHIER_FI2C_BRST_FOEN | UNIPHIER_FI2C_BRST_RSCL,
+	       priv->membase + UNIPHIER_FI2C_BRST);
+}
+
+static void uniphier_fi2c_recover(struct uniphier_fi2c_priv *priv)
+{
+	uniphier_fi2c_reset(priv);
+	i2c_recover_bus(&priv->adap);
+}
+
+static int uniphier_fi2c_master_xfer_one(struct i2c_adapter *adap,
+					 struct i2c_msg *msg, bool stop)
+{
+	struct uniphier_fi2c_priv *priv = i2c_get_adapdata(adap);
+	bool is_read = msg->flags & I2C_M_RD;
+	unsigned long time_left;
+
+	dev_dbg(&adap->dev, "%s: addr=0x%02x, len=%d, stop=%d\n",
+		is_read ? "receive" : "transmit", msg->addr, msg->len, stop);
+
+	priv->len = msg->len;
+	priv->buf = msg->buf;
+	priv->enabled_irqs = UNIPHIER_FI2C_INT_FAULTS;
+	priv->error = 0;
+	priv->flags = 0;
+
+	if (stop)
+		priv->flags |= UNIPHIER_FI2C_STOP;
+
+	reinit_completion(&priv->comp);
+	uniphier_fi2c_clear_irqs(priv);
+	writel(UNIPHIER_FI2C_RST_TBRST | UNIPHIER_FI2C_RST_RBRST,
+	       priv->membase + UNIPHIER_FI2C_RST);	/* reset TX/RX FIFO */
+
+	if (is_read)
+		uniphier_fi2c_rx_init(priv, msg->addr);
+	else
+		uniphier_fi2c_tx_init(priv, msg->addr);
+
+	uniphier_fi2c_set_irqs(priv);
+
+	dev_dbg(&adap->dev, "start condition\n");
+	writel(UNIPHIER_FI2C_CR_MST | UNIPHIER_FI2C_CR_STA,
+	       priv->membase + UNIPHIER_FI2C_CR);
+
+	time_left = wait_for_completion_timeout(&priv->comp, adap->timeout);
+	if (!time_left) {
+		dev_err(&adap->dev, "transaction timeout.\n");
+		uniphier_fi2c_recover(priv);
+		return -ETIMEDOUT;
+	}
+	dev_dbg(&adap->dev, "complete\n");
+
+	if (unlikely(priv->flags & UNIPHIER_FI2C_DEFER_STOP_COMP)) {
+		u32 status = readl(priv->membase + UNIPHIER_FI2C_SR);
+
+		if (!(status & UNIPHIER_FI2C_SR_STS) ||
+		    status & UNIPHIER_FI2C_SR_BB) {
+			dev_err(&adap->dev,
+				"stop condition was not completed.\n");
+			uniphier_fi2c_recover(priv);
+			return -EBUSY;
+		}
+	}
+
+	return priv->error;
+}
+
+static int uniphier_fi2c_check_bus_busy(struct i2c_adapter *adap)
+{
+	struct uniphier_fi2c_priv *priv = i2c_get_adapdata(adap);
+
+	if (readl(priv->membase + UNIPHIER_FI2C_SR) & UNIPHIER_FI2C_SR_DB) {
+		if (priv->busy_cnt++ > 3) {
+			/*
+			 * If bus busy continues too long, it is probably
+			 * in a wrong state.  Try bus recovery.
+			 */
+			uniphier_fi2c_recover(priv);
+			priv->busy_cnt = 0;
+		}
+
+		return -EAGAIN;
+	}
+
+	priv->busy_cnt = 0;
+	return 0;
+}
+
+static int uniphier_fi2c_master_xfer(struct i2c_adapter *adap,
+				     struct i2c_msg *msgs, int num)
+{
+	struct i2c_msg *msg, *emsg = msgs + num;
+	int ret;
+
+	ret = uniphier_fi2c_check_bus_busy(adap);
+	if (ret)
+		return ret;
+
+	for (msg = msgs; msg < emsg; msg++) {
+		/* If next message is read, skip the stop condition */
+		bool stop = !(msg + 1 < emsg && msg[1].flags & I2C_M_RD);
+		/* but, force it if I2C_M_STOP is set */
+		if (msg->flags & I2C_M_STOP)
+			stop = true;
+
+		ret = uniphier_fi2c_master_xfer_one(adap, msg, stop);
+		if (ret)
+			return ret;
+	}
+
+	return num;
+}
+
+static u32 uniphier_fi2c_functionality(struct i2c_adapter *adap)
+{
+	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+static const struct i2c_algorithm uniphier_fi2c_algo = {
+	.master_xfer = uniphier_fi2c_master_xfer,
+	.functionality = uniphier_fi2c_functionality,
+};
+
+static int uniphier_fi2c_get_scl(struct i2c_adapter *adap)
+{
+	struct uniphier_fi2c_priv *priv = i2c_get_adapdata(adap);
+
+	return !!(readl(priv->membase + UNIPHIER_FI2C_BM) &
+							UNIPHIER_FI2C_BM_SCLS);
+}
+
+static void uniphier_fi2c_set_scl(struct i2c_adapter *adap, int val)
+{
+	struct uniphier_fi2c_priv *priv = i2c_get_adapdata(adap);
+
+	writel(val ? UNIPHIER_FI2C_BRST_RSCL : 0,
+	       priv->membase + UNIPHIER_FI2C_BRST);
+}
+
+static int uniphier_fi2c_get_sda(struct i2c_adapter *adap)
+{
+	struct uniphier_fi2c_priv *priv = i2c_get_adapdata(adap);
+
+	return !!(readl(priv->membase + UNIPHIER_FI2C_BM) &
+							UNIPHIER_FI2C_BM_SDAS);
+}
+
+static void uniphier_fi2c_unprepare_recovery(struct i2c_adapter *adap)
+{
+	uniphier_fi2c_prepare_operation(i2c_get_adapdata(adap));
+}
+
+static struct i2c_bus_recovery_info uniphier_fi2c_bus_recovery_info = {
+	.recover_bus = i2c_generic_scl_recovery,
+	.get_scl = uniphier_fi2c_get_scl,
+	.set_scl = uniphier_fi2c_set_scl,
+	.get_sda = uniphier_fi2c_get_sda,
+	.unprepare_recovery = uniphier_fi2c_unprepare_recovery,
+};
+
+static int uniphier_fi2c_clk_init(struct device *dev,
+				  struct uniphier_fi2c_priv *priv)
+{
+	struct device_node *np = dev->of_node;
+	unsigned long clk_rate;
+	u32 bus_speed, clk_count;
+	int ret;
+
+	if (of_property_read_u32(np, "clock-frequency", &bus_speed))
+		bus_speed = UNIPHIER_FI2C_DEFAULT_SPEED;
+
+	if (bus_speed > UNIPHIER_FI2C_MAX_SPEED)
+		bus_speed = UNIPHIER_FI2C_MAX_SPEED;
+
+	/* Get input clk rate through clk driver */
+	priv->clk = devm_clk_get(dev, NULL);
+	if (IS_ERR(priv->clk)) {
+		dev_err(dev, "failed to get clock\n");
+		return PTR_ERR(priv->clk);
+	}
+
+	ret = clk_prepare_enable(priv->clk);
+	if (ret)
+		return ret;
+
+	clk_rate = clk_get_rate(priv->clk);
+
+	uniphier_fi2c_reset(priv);
+
+	clk_count = clk_rate / bus_speed;
+
+	writel(clk_count, priv->membase + UNIPHIER_FI2C_CYC);
+	writel(clk_count / 2, priv->membase + UNIPHIER_FI2C_LCTL);
+	writel(clk_count / 2, priv->membase + UNIPHIER_FI2C_SSUT);
+	writel(clk_count / 16, priv->membase + UNIPHIER_FI2C_DSUT);
+
+	uniphier_fi2c_prepare_operation(priv);
+
+	return 0;
+}
+
+static int uniphier_fi2c_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct uniphier_fi2c_priv *priv;
+	struct resource *regs;
+	int irq;
+	int ret;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	priv->membase = devm_ioremap_resource(dev, regs);
+	if (IS_ERR(priv->membase))
+		return PTR_ERR(priv->membase);
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		dev_err(dev, "failed to get IRQ number");
+		return irq;
+	}
+
+	init_completion(&priv->comp);
+	priv->adap.owner = THIS_MODULE;
+	priv->adap.algo = &uniphier_fi2c_algo;
+	priv->adap.dev.parent = dev;
+	priv->adap.dev.of_node = dev->of_node;
+	strlcpy(priv->adap.name, "UniPhier FI2C", sizeof(priv->adap.name));
+	priv->adap.bus_recovery_info = &uniphier_fi2c_bus_recovery_info;
+	i2c_set_adapdata(&priv->adap, priv);
+	platform_set_drvdata(pdev, priv);
+
+	ret = uniphier_fi2c_clk_init(dev, priv);
+	if (ret)
+		return ret;
+
+	ret = devm_request_irq(dev, irq, uniphier_fi2c_interrupt, 0,
+			       pdev->name, priv);
+	if (ret) {
+		dev_err(dev, "failed to request irq %d\n", irq);
+		goto err;
+	}
+
+	ret = i2c_add_adapter(&priv->adap);
+	if (ret) {
+		dev_err(dev, "failed to add I2C adapter\n");
+		goto err;
+	}
+
+err:
+	if (ret)
+		clk_disable_unprepare(priv->clk);
+
+	return ret;
+}
+
+static int uniphier_fi2c_remove(struct platform_device *pdev)
+{
+	struct uniphier_fi2c_priv *priv = platform_get_drvdata(pdev);
+
+	i2c_del_adapter(&priv->adap);
+	clk_disable_unprepare(priv->clk);
+
+	return 0;
+}
+
+static const struct of_device_id uniphier_fi2c_match[] = {
+	{ .compatible = "socionext,uniphier-fi2c" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, uniphier_fi2c_match);
+
+static struct platform_driver uniphier_fi2c_drv = {
+	.probe  = uniphier_fi2c_probe,
+	.remove = uniphier_fi2c_remove,
+	.driver = {
+		.name  = "uniphier-fi2c",
+		.of_match_table = uniphier_fi2c_match,
+	},
+};
+module_platform_driver(uniphier_fi2c_drv);
+
+MODULE_AUTHOR("Masahiro Yamada <yamada.masahiro@socionext.com>");
+MODULE_DESCRIPTION("UniPhier FIFO-builtin I2C bus driver");
+MODULE_LICENSE("GPL");

drivers/i2c/busses/i2c-uniphier.c

@@ -0,0 +1,441 @@
+/*
+ * Copyright (C) 2015 Masahiro Yamada <yamada.masahiro@socionext.com>
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/clk.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+#define UNIPHIER_I2C_DTRM	0x00	/* TX register */
+#define     UNIPHIER_I2C_DTRM_IRQEN	BIT(11)	/* enable interrupt */
+#define     UNIPHIER_I2C_DTRM_STA	BIT(10)	/* start condition */
+#define     UNIPHIER_I2C_DTRM_STO	BIT(9)	/* stop condition */
+#define     UNIPHIER_I2C_DTRM_NACK	BIT(8)	/* do not return ACK */
+#define     UNIPHIER_I2C_DTRM_RD	BIT(0)	/* read transaction */
+#define UNIPHIER_I2C_DREC	0x04	/* RX register */
+#define     UNIPHIER_I2C_DREC_MST	BIT(14)	/* 1 = master, 0 = slave */
+#define     UNIPHIER_I2C_DREC_TX	BIT(13)	/* 1 = transmit, 0 = receive */
+#define     UNIPHIER_I2C_DREC_STS	BIT(12)	/* stop condition detected */
+#define     UNIPHIER_I2C_DREC_LRB	BIT(11)	/* no ACK */
+#define     UNIPHIER_I2C_DREC_LAB	BIT(9)	/* arbitration lost */
+#define     UNIPHIER_I2C_DREC_BBN	BIT(8)	/* bus not busy */
+#define UNIPHIER_I2C_MYAD	0x08	/* slave address */
+#define UNIPHIER_I2C_CLK	0x0c	/* clock frequency control */
+#define UNIPHIER_I2C_BRST	0x10	/* bus reset */
+#define     UNIPHIER_I2C_BRST_FOEN	BIT(1)	/* normal operation */
+#define     UNIPHIER_I2C_BRST_RSCL	BIT(0)	/* release SCL */
+#define UNIPHIER_I2C_HOLD	0x14	/* hold time control */
+#define UNIPHIER_I2C_BSTS	0x18	/* bus status monitor */
+#define     UNIPHIER_I2C_BSTS_SDA	BIT(1)	/* readback of SDA line */
+#define     UNIPHIER_I2C_BSTS_SCL	BIT(0)	/* readback of SCL line */
+#define UNIPHIER_I2C_NOISE	0x1c	/* noise filter control */
+#define UNIPHIER_I2C_SETUP	0x20	/* setup time control */
+
+#define UNIPHIER_I2C_DEFAULT_SPEED	100000
+#define UNIPHIER_I2C_MAX_SPEED		400000
+
+struct uniphier_i2c_priv {
+	struct completion comp;
+	struct i2c_adapter adap;
+	void __iomem *membase;
+	struct clk *clk;
+	unsigned int busy_cnt;
+};
+
+static irqreturn_t uniphier_i2c_interrupt(int irq, void *dev_id)
+{
+	struct uniphier_i2c_priv *priv = dev_id;
+
+	/*
+	 * This hardware uses edge triggered interrupt.  Do not touch the
+	 * hardware registers in this handler to make sure to catch the next
+	 * interrupt edge.  Just send a complete signal and return.
+	 */
+	complete(&priv->comp);
+
+	return IRQ_HANDLED;
+}
+
+static int uniphier_i2c_xfer_byte(struct i2c_adapter *adap, u32 txdata,
+				  u32 *rxdatap)
+{
+	struct uniphier_i2c_priv *priv = i2c_get_adapdata(adap);
+	unsigned long time_left;
+	u32 rxdata;
+
+	reinit_completion(&priv->comp);
+
+	txdata |= UNIPHIER_I2C_DTRM_IRQEN;
+	dev_dbg(&adap->dev, "write data: 0x%04x\n", txdata);
+	writel(txdata, priv->membase + UNIPHIER_I2C_DTRM);
+
+	time_left = wait_for_completion_timeout(&priv->comp, adap->timeout);
+	if (unlikely(!time_left)) {
+		dev_err(&adap->dev, "transaction timeout\n");
+		return -ETIMEDOUT;
+	}
+
+	rxdata = readl(priv->membase + UNIPHIER_I2C_DREC);
+	dev_dbg(&adap->dev, "read data: 0x%04x\n", rxdata);
+
+	if (rxdatap)
+		*rxdatap = rxdata;
+
+	return 0;
+}
+
+static int uniphier_i2c_send_byte(struct i2c_adapter *adap, u32 txdata)
+{
+	u32 rxdata;
+	int ret;
+
+	ret = uniphier_i2c_xfer_byte(adap, txdata, &rxdata);
+	if (ret)
+		return ret;
+
+	if (unlikely(rxdata & UNIPHIER_I2C_DREC_LAB)) {
+		dev_dbg(&adap->dev, "arbitration lost\n");
+		return -EAGAIN;
+	}
+	if (unlikely(rxdata & UNIPHIER_I2C_DREC_LRB)) {
+		dev_dbg(&adap->dev, "could not get ACK\n");
+		return -ENXIO;
+	}
+
+	return 0;
+}
+
+static int uniphier_i2c_tx(struct i2c_adapter *adap, u16 addr, u16 len,
+			   const u8 *buf)
+{
+	int ret;
+
+	dev_dbg(&adap->dev, "start condition\n");
+	ret = uniphier_i2c_send_byte(adap, addr << 1 |
+				     UNIPHIER_I2C_DTRM_STA |
+				     UNIPHIER_I2C_DTRM_NACK);
+	if (ret)
+		return ret;
+
+	while (len--) {
+		ret = uniphier_i2c_send_byte(adap,
+					     UNIPHIER_I2C_DTRM_NACK | *buf++);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static int uniphier_i2c_rx(struct i2c_adapter *adap, u16 addr, u16 len,
+			   u8 *buf)
+{
+	int ret;
+
+	dev_dbg(&adap->dev, "start condition\n");
+	ret = uniphier_i2c_send_byte(adap, addr << 1 |
+				     UNIPHIER_I2C_DTRM_STA |
+				     UNIPHIER_I2C_DTRM_NACK |
+				     UNIPHIER_I2C_DTRM_RD);
+	if (ret)
+		return ret;
+
+	while (len--) {
+		u32 rxdata;
+
+		ret = uniphier_i2c_xfer_byte(adap,
+					     len ? 0 : UNIPHIER_I2C_DTRM_NACK,
+					     &rxdata);
+		if (ret)
+			return ret;
+		*buf++ = rxdata;
+	}
+
+	return 0;
+}
+
+static int uniphier_i2c_stop(struct i2c_adapter *adap)
+{
+	dev_dbg(&adap->dev, "stop condition\n");
+	return uniphier_i2c_send_byte(adap, UNIPHIER_I2C_DTRM_STO |
+				      UNIPHIER_I2C_DTRM_NACK);
+}
+
+static int uniphier_i2c_master_xfer_one(struct i2c_adapter *adap,
+					struct i2c_msg *msg, bool stop)
+{
+	bool is_read = msg->flags & I2C_M_RD;
+	bool recovery = false;
+	int ret;
+
+	dev_dbg(&adap->dev, "%s: addr=0x%02x, len=%d, stop=%d\n",
+		is_read ? "receive" : "transmit", msg->addr, msg->len, stop);
+
+	if (is_read)
+		ret = uniphier_i2c_rx(adap, msg->addr, msg->len, msg->buf);
+	else
+		ret = uniphier_i2c_tx(adap, msg->addr, msg->len, msg->buf);
+
+	if (ret == -EAGAIN) /* could not acquire bus. bail out without STOP */
+		return ret;
+
+	if (ret == -ETIMEDOUT) {
+		/* This error is fatal.  Needs recovery. */
+		stop = false;
+		recovery = true;
+	}
+
+	if (stop) {
+		int ret2 = uniphier_i2c_stop(adap);
+
+		if (ret2) {
+			/* Failed to issue STOP.  The bus needs recovery. */
+			recovery = true;
+			ret = ret ?: ret2;
+		}
+	}
+
+	if (recovery)
+		i2c_recover_bus(adap);
+
+	return ret;
+}
+
+static int uniphier_i2c_check_bus_busy(struct i2c_adapter *adap)
+{
+	struct uniphier_i2c_priv *priv = i2c_get_adapdata(adap);
+
+	if (!(readl(priv->membase + UNIPHIER_I2C_DREC) &
+						UNIPHIER_I2C_DREC_BBN)) {
+		if (priv->busy_cnt++ > 3) {
+			/*
+			 * If bus busy continues too long, it is probably
+			 * in a wrong state.  Try bus recovery.
+			 */
+			i2c_recover_bus(adap);
+			priv->busy_cnt = 0;
+		}
+
+		return -EAGAIN;
+	}
+
+	priv->busy_cnt = 0;
+	return 0;
+}
+
+static int uniphier_i2c_master_xfer(struct i2c_adapter *adap,
+				    struct i2c_msg *msgs, int num)
+{
+	struct i2c_msg *msg, *emsg = msgs + num;
+	int ret;
+
+	ret = uniphier_i2c_check_bus_busy(adap);
+	if (ret)
+		return ret;
+
+	for (msg = msgs; msg < emsg; msg++) {
+		/* If next message is read, skip the stop condition */
+		bool stop = !(msg + 1 < emsg && msg[1].flags & I2C_M_RD);
+		/* but, force it if I2C_M_STOP is set */
+		if (msg->flags & I2C_M_STOP)
+			stop = true;
+
+		ret = uniphier_i2c_master_xfer_one(adap, msg, stop);
+		if (ret)
+			return ret;
+	}
+
+	return num;
+}
+
+static u32 uniphier_i2c_functionality(struct i2c_adapter *adap)
+{
+	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+static const struct i2c_algorithm uniphier_i2c_algo = {
+	.master_xfer = uniphier_i2c_master_xfer,
+	.functionality = uniphier_i2c_functionality,
+};
+
+static void uniphier_i2c_reset(struct uniphier_i2c_priv *priv, bool reset_on)
+{
+	u32 val = UNIPHIER_I2C_BRST_RSCL;
+
+	val |= reset_on ? 0 : UNIPHIER_I2C_BRST_FOEN;
+	writel(val, priv->membase + UNIPHIER_I2C_BRST);
+}
+
+static int uniphier_i2c_get_scl(struct i2c_adapter *adap)
+{
+	struct uniphier_i2c_priv *priv = i2c_get_adapdata(adap);
+
+	return !!(readl(priv->membase + UNIPHIER_I2C_BSTS) &
+							UNIPHIER_I2C_BSTS_SCL);
+}
+
+static void uniphier_i2c_set_scl(struct i2c_adapter *adap, int val)
+{
+	struct uniphier_i2c_priv *priv = i2c_get_adapdata(adap);
+
+	writel(val ? UNIPHIER_I2C_BRST_RSCL : 0,
+	       priv->membase + UNIPHIER_I2C_BRST);
+}
+
+static int uniphier_i2c_get_sda(struct i2c_adapter *adap)
+{
+	struct uniphier_i2c_priv *priv = i2c_get_adapdata(adap);
+
+	return !!(readl(priv->membase + UNIPHIER_I2C_BSTS) &
+							UNIPHIER_I2C_BSTS_SDA);
+}
+
+static void uniphier_i2c_unprepare_recovery(struct i2c_adapter *adap)
+{
+	uniphier_i2c_reset(i2c_get_adapdata(adap), false);
+}
+
+static struct i2c_bus_recovery_info uniphier_i2c_bus_recovery_info = {
+	.recover_bus = i2c_generic_scl_recovery,
+	.get_scl = uniphier_i2c_get_scl,
+	.set_scl = uniphier_i2c_set_scl,
+	.get_sda = uniphier_i2c_get_sda,
+	.unprepare_recovery = uniphier_i2c_unprepare_recovery,
+};
+
+static int uniphier_i2c_clk_init(struct device *dev,
+				 struct uniphier_i2c_priv *priv)
+{
+	struct device_node *np = dev->of_node;
+	unsigned long clk_rate;
+	u32 bus_speed;
+	int ret;
+
+	if (of_property_read_u32(np, "clock-frequency", &bus_speed))
+		bus_speed = UNIPHIER_I2C_DEFAULT_SPEED;
+
+	if (bus_speed > UNIPHIER_I2C_MAX_SPEED)
+		bus_speed = UNIPHIER_I2C_MAX_SPEED;
+
+	/* Get input clk rate through clk driver */
+	priv->clk = devm_clk_get(dev, NULL);
+	if (IS_ERR(priv->clk)) {
+		dev_err(dev, "failed to get clock\n");
+		return PTR_ERR(priv->clk);
+	}
+
+	ret = clk_prepare_enable(priv->clk);
+	if (ret)
+		return ret;
+
+	clk_rate = clk_get_rate(priv->clk);
+
+	uniphier_i2c_reset(priv, true);
+
+	writel((clk_rate / bus_speed / 2 << 16) | (clk_rate / bus_speed),
+	       priv->membase + UNIPHIER_I2C_CLK);
+
+	uniphier_i2c_reset(priv, false);
+
+	return 0;
+}
+
+static int uniphier_i2c_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct uniphier_i2c_priv *priv;
+	struct resource *regs;
+	int irq;
+	int ret;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	priv->membase = devm_ioremap_resource(dev, regs);
+	if (IS_ERR(priv->membase))
+		return PTR_ERR(priv->membase);
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		dev_err(dev, "failed to get IRQ number");
+		return irq;
+	}
+
+	init_completion(&priv->comp);
+	priv->adap.owner = THIS_MODULE;
+	priv->adap.algo = &uniphier_i2c_algo;
+	priv->adap.dev.parent = dev;
+	priv->adap.dev.of_node = dev->of_node;
+	strlcpy(priv->adap.name, "UniPhier I2C", sizeof(priv->adap.name));
+	priv->adap.bus_recovery_info = &uniphier_i2c_bus_recovery_info;
+	i2c_set_adapdata(&priv->adap, priv);
+	platform_set_drvdata(pdev, priv);
+
+	ret = uniphier_i2c_clk_init(dev, priv);
+	if (ret)
+		return ret;
+
+	ret = devm_request_irq(dev, irq, uniphier_i2c_interrupt, 0, pdev->name,
+			       priv);
+	if (ret) {
+		dev_err(dev, "failed to request irq %d\n", irq);
+		goto err;
+	}
+
+	ret = i2c_add_adapter(&priv->adap);
+	if (ret) {
+		dev_err(dev, "failed to add I2C adapter\n");
+		goto err;
+	}
+
+err:
+	if (ret)
+		clk_disable_unprepare(priv->clk);
+
+	return ret;
+}
+
+static int uniphier_i2c_remove(struct platform_device *pdev)
+{
+	struct uniphier_i2c_priv *priv = platform_get_drvdata(pdev);
+
+	i2c_del_adapter(&priv->adap);
+	clk_disable_unprepare(priv->clk);
+
+	return 0;
+}
+
+static const struct of_device_id uniphier_i2c_match[] = {
+	{ .compatible = "socionext,uniphier-i2c" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, uniphier_i2c_match);
+
+static struct platform_driver uniphier_i2c_drv = {
+	.probe  = uniphier_i2c_probe,
+	.remove = uniphier_i2c_remove,
+	.driver = {
+		.name  = "uniphier-i2c",
+		.of_match_table = uniphier_i2c_match,
+	},
+};
+module_platform_driver(uniphier_i2c_drv);
+
+MODULE_AUTHOR("Masahiro Yamada <yamada.masahiro@socionext.com>");
+MODULE_DESCRIPTION("UniPhier I2C bus driver");
+MODULE_LICENSE("GPL");

drivers/i2c/i2c-core.c

@@ -99,27 +99,40 @@ struct gsb_buffer {
 	};
 } __packed;
 
-static int acpi_i2c_add_resource(struct acpi_resource *ares, void *data)
+struct acpi_i2c_lookup {
+	struct i2c_board_info *info;
+	acpi_handle adapter_handle;
+	acpi_handle device_handle;
+};
+
+static int acpi_i2c_find_address(struct acpi_resource *ares, void *data)
 {
-	struct i2c_board_info *info = data;
+	struct acpi_i2c_lookup *lookup = data;
+	struct i2c_board_info *info = lookup->info;
+	struct acpi_resource_i2c_serialbus *sb;
+	acpi_handle adapter_handle;
+	acpi_status status;
 
-	if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) {
-		struct acpi_resource_i2c_serialbus *sb;
+	if (info->addr || ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
+		return 1;
 
-		sb = &ares->data.i2c_serial_bus;
-		if (!info->addr && sb->type == ACPI_RESOURCE_SERIAL_TYPE_I2C) {
-			info->addr = sb->slave_address;
-			if (sb->access_mode == ACPI_I2C_10BIT_MODE)
-				info->flags |= I2C_CLIENT_TEN;
-		}
-	} else if (!info->irq) {
-		struct resource r;
+	sb = &ares->data.i2c_serial_bus;
+	if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C)
+		return 1;
 
-		if (acpi_dev_resource_interrupt(ares, 0, &r))
-			info->irq = r.start;
+	/*
+	 * Extract the ResourceSource and make sure that the handle matches
+	 * with the I2C adapter handle.
+	 */
+	status = acpi_get_handle(lookup->device_handle,
+				 sb->resource_source.string_ptr,
+				 &adapter_handle);
+	if (ACPI_SUCCESS(status) && adapter_handle == lookup->adapter_handle) {
+		info->addr = sb->slave_address;
+		if (sb->access_mode == ACPI_I2C_10BIT_MODE)
+			info->flags |= I2C_CLIENT_TEN;
 	}
 
-	/* Tell the ACPI core to skip this resource */
 	return 1;
 }
 
@@ -128,6 +141,8 @@ static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level,
 {
 	struct i2c_adapter *adapter = data;
 	struct list_head resource_list;
+	struct acpi_i2c_lookup lookup;
+	struct resource_entry *entry;
 	struct i2c_board_info info;
 	struct acpi_device *adev;
 	int ret;
@@ -140,14 +155,37 @@ static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level,
 	memset(&info, 0, sizeof(info));
 	info.fwnode = acpi_fwnode_handle(adev);
 
+	memset(&lookup, 0, sizeof(lookup));
+	lookup.adapter_handle = ACPI_HANDLE(&adapter->dev);
+	lookup.device_handle = handle;
+	lookup.info = &info;
+
+	/*
+	 * Look up for I2cSerialBus resource with ResourceSource that
+	 * matches with this adapter.
+	 */
 	INIT_LIST_HEAD(&resource_list);
 	ret = acpi_dev_get_resources(adev, &resource_list,
-				     acpi_i2c_add_resource, &info);
+				     acpi_i2c_find_address, &lookup);
 	acpi_dev_free_resource_list(&resource_list);
 
 	if (ret < 0 || !info.addr)
 		return AE_OK;
 
+	/* Then fill IRQ number if any */
+	ret = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
+	if (ret < 0)
+		return AE_OK;
+
+	resource_list_for_each_entry(entry, &resource_list) {
+		if (resource_type(entry->res) == IORESOURCE_IRQ) {
+			info.irq = entry->res->start;
+			break;
+		}
+	}
+
+	acpi_dev_free_resource_list(&resource_list);
+
 	adev->power.flags.ignore_parent = true;
 	strlcpy(info.type, dev_name(&adev->dev), sizeof(info.type));
 	if (!i2c_new_device(adapter, &info)) {
@@ -160,6 +198,8 @@ static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level,
 	return AE_OK;
 }
 
+#define ACPI_I2C_MAX_SCAN_DEPTH 32
+
 /**
  * acpi_i2c_register_devices - enumerate I2C slave devices behind adapter
  * @adap: pointer to adapter
@@ -170,17 +210,13 @@ static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level,
  */
 static void acpi_i2c_register_devices(struct i2c_adapter *adap)
 {
-	acpi_handle handle;
 	acpi_status status;
 
-	if (!adap->dev.parent)
-		return;
-
-	handle = ACPI_HANDLE(adap->dev.parent);
-	if (!handle)
+	if (!has_acpi_companion(&adap->dev))
 		return;
 
-	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
+	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
+				     ACPI_I2C_MAX_SCAN_DEPTH,
 				     acpi_i2c_add_device, NULL,
 				     adap, NULL);
 	if (ACPI_FAILURE(status))

drivers/i2c/i2c-dev.c

@@ -235,7 +235,7 @@ static int i2cdev_check_addr(struct i2c_adapter *adapter, unsigned int addr)
 	return result;
 }
 
-static noinline int i2cdev_ioctl_rdrw(struct i2c_client *client,
+static noinline int i2cdev_ioctl_rdwr(struct i2c_client *client,
 		unsigned long arg)
 {
 	struct i2c_rdwr_ioctl_data rdwr_arg;
@@ -250,7 +250,7 @@ static noinline int i2cdev_ioctl_rdrw(struct i2c_client *client,
 
 	/* Put an arbitrary limit on the number of messages that can
 	 * be sent at once */
-	if (rdwr_arg.nmsgs > I2C_RDRW_IOCTL_MAX_MSGS)
+	if (rdwr_arg.nmsgs > I2C_RDWR_IOCTL_MAX_MSGS)
 		return -EINVAL;
 
 	rdwr_pa = memdup_user(rdwr_arg.msgs,
@@ -421,16 +421,6 @@ static long i2cdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 	switch (cmd) {
 	case I2C_SLAVE:
 	case I2C_SLAVE_FORCE:
-		/* NOTE:  devices set up to work with "new style" drivers
-		 * can't use I2C_SLAVE, even when the device node is not
-		 * bound to a driver.  Only I2C_SLAVE_FORCE will work.
-		 *
-		 * Setting the PEC flag here won't affect kernel drivers,
-		 * which will be using the i2c_client node registered with
-		 * the driver model core.  Likewise, when that client has
-		 * the PEC flag already set, the i2c-dev driver won't see
-		 * (or use) this setting.
-		 */
 		if ((arg > 0x3ff) ||
 		    (((client->flags & I2C_M_TEN) == 0) && arg > 0x7f))
 			return -EINVAL;
@@ -446,6 +436,13 @@ static long i2cdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 			client->flags &= ~I2C_M_TEN;
 		return 0;
 	case I2C_PEC:
+		/*
+		 * Setting the PEC flag here won't affect kernel drivers,
+		 * which will be using the i2c_client node registered with
+		 * the driver model core.  Likewise, when that client has
+		 * the PEC flag already set, the i2c-dev driver won't see
+		 * (or use) this setting.
+		 */
 		if (arg)
 			client->flags |= I2C_CLIENT_PEC;
 		else
@@ -456,7 +453,7 @@ static long i2cdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 		return put_user(funcs, (unsigned long __user *)arg);
 
 	case I2C_RDWR:
-		return i2cdev_ioctl_rdrw(client, arg);
+		return i2cdev_ioctl_rdwr(client, arg);
 
 	case I2C_SMBUS:
 		return i2cdev_ioctl_smbus(client, arg);

drivers/i2c/i2c-mux.c

@@ -25,6 +25,7 @@
 #include <linux/i2c.h>
 #include <linux/i2c-mux.h>
 #include <linux/of.h>
+#include <linux/acpi.h>
 
 /* multiplexer per channel data */
 struct i2c_mux_priv {
@@ -173,6 +174,13 @@ struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent,
 		}
 	}
 
+	/*
+	 * Associate the mux channel with an ACPI node.
+	 */
+	if (has_acpi_companion(mux_dev))
+		acpi_preset_companion(&priv->adap.dev, ACPI_COMPANION(mux_dev),
+				      chan_id);
+
 	if (force_nr) {
 		priv->adap.nr = force_nr;
 		ret = i2c_add_numbered_adapter(&priv->adap);

fs/compat_ioctl.c

@@ -686,7 +686,7 @@ static int do_i2c_rdwr_ioctl(unsigned int fd, unsigned int cmd,
 
 	if (get_user(nmsgs, &udata->nmsgs))
 		return -EFAULT;
-	if (nmsgs > I2C_RDRW_IOCTL_MAX_MSGS)
+	if (nmsgs > I2C_RDWR_IOCTL_MAX_MSGS)
 		return -EINVAL;
 
 	if (get_user(datap, &udata->msgs))

include/linux/acpi.h

@@ -514,6 +514,11 @@ static inline bool has_acpi_companion(struct device *dev)
 	return false;
 }
 
+static inline void acpi_preset_companion(struct device *dev,
+					 struct acpi_device *parent, u64 addr)
+{
+}
+
 static inline const char *acpi_dev_name(struct acpi_device *adev)
 {
 	return NULL;

include/linux/i2c-ocores.h

@@ -15,6 +15,7 @@ struct ocores_i2c_platform_data {
 	u32 reg_shift; /* register offset shift value */
 	u32 reg_io_width; /* register io read/write width */
 	u32 clock_khz; /* input clock in kHz */
+	bool big_endian; /* registers are big endian */
 	u8 num_devices; /* number of devices in the devices list */
 	struct i2c_board_info const *devices; /* devices connected to the bus */
 };

include/linux/i2c/i2c-rcar.h

@@ -1,10 +0,0 @@
-#ifndef __I2C_R_CAR_H__
-#define __I2C_R_CAR_H__
-
-#include <linux/platform_device.h>
-
-struct i2c_rcar_platform_data {
-	u32 bus_speed;
-};
-
-#endif /* __I2C_R_CAR_H__ */

include/uapi/linux/i2c-dev.h

@@ -66,7 +66,9 @@ struct i2c_rdwr_ioctl_data {
 	__u32 nmsgs;			/* number of i2c_msgs */
 };
 
-#define  I2C_RDRW_IOCTL_MAX_MSGS	42
+#define  I2C_RDWR_IOCTL_MAX_MSGS	42
+/* Originally defined with a typo, keep it for compatibility */
+#define  I2C_RDRW_IOCTL_MAX_MSGS	I2C_RDWR_IOCTL_MAX_MSGS
 
 
 #endif /* _UAPI_LINUX_I2C_DEV_H */