sc16is7xx.c 36 KB

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  1. /*
  2. * SC16IS7xx tty serial driver - Copyright (C) 2014 GridPoint
  3. * Author: Jon Ringle <jringle@gridpoint.com>
  4. *
  5. * Based on max310x.c, by Alexander Shiyan <shc_work@mail.ru>
  6. *
  7. * This program is free software; you can redistribute it and/or modify
  8. * it under the terms of the GNU General Public License as published by
  9. * the Free Software Foundation; either version 2 of the License, or
  10. * (at your option) any later version.
  11. *
  12. */
  13. #include <linux/bitops.h>
  14. #include <linux/clk.h>
  15. #include <linux/delay.h>
  16. #include <linux/device.h>
  17. #include <linux/gpio.h>
  18. #include <linux/i2c.h>
  19. #include <linux/module.h>
  20. #include <linux/of.h>
  21. #include <linux/of_device.h>
  22. #include <linux/regmap.h>
  23. #include <linux/serial_core.h>
  24. #include <linux/serial.h>
  25. #include <linux/tty.h>
  26. #include <linux/tty_flip.h>
  27. #include <linux/uaccess.h>
  28. #define SC16IS7XX_NAME "sc16is7xx"
  29. /* SC16IS7XX register definitions */
  30. #define SC16IS7XX_RHR_REG (0x00) /* RX FIFO */
  31. #define SC16IS7XX_THR_REG (0x00) /* TX FIFO */
  32. #define SC16IS7XX_IER_REG (0x01) /* Interrupt enable */
  33. #define SC16IS7XX_IIR_REG (0x02) /* Interrupt Identification */
  34. #define SC16IS7XX_FCR_REG (0x02) /* FIFO control */
  35. #define SC16IS7XX_LCR_REG (0x03) /* Line Control */
  36. #define SC16IS7XX_MCR_REG (0x04) /* Modem Control */
  37. #define SC16IS7XX_LSR_REG (0x05) /* Line Status */
  38. #define SC16IS7XX_MSR_REG (0x06) /* Modem Status */
  39. #define SC16IS7XX_SPR_REG (0x07) /* Scratch Pad */
  40. #define SC16IS7XX_TXLVL_REG (0x08) /* TX FIFO level */
  41. #define SC16IS7XX_RXLVL_REG (0x09) /* RX FIFO level */
  42. #define SC16IS7XX_IODIR_REG (0x0a) /* I/O Direction
  43. * - only on 75x/76x
  44. */
  45. #define SC16IS7XX_IOSTATE_REG (0x0b) /* I/O State
  46. * - only on 75x/76x
  47. */
  48. #define SC16IS7XX_IOINTENA_REG (0x0c) /* I/O Interrupt Enable
  49. * - only on 75x/76x
  50. */
  51. #define SC16IS7XX_IOCONTROL_REG (0x0e) /* I/O Control
  52. * - only on 75x/76x
  53. */
  54. #define SC16IS7XX_EFCR_REG (0x0f) /* Extra Features Control */
  55. /* TCR/TLR Register set: Only if ((MCR[2] == 1) && (EFR[4] == 1)) */
  56. #define SC16IS7XX_TCR_REG (0x06) /* Transmit control */
  57. #define SC16IS7XX_TLR_REG (0x07) /* Trigger level */
  58. /* Special Register set: Only if ((LCR[7] == 1) && (LCR != 0xBF)) */
  59. #define SC16IS7XX_DLL_REG (0x00) /* Divisor Latch Low */
  60. #define SC16IS7XX_DLH_REG (0x01) /* Divisor Latch High */
  61. /* Enhanced Register set: Only if (LCR == 0xBF) */
  62. #define SC16IS7XX_EFR_REG (0x02) /* Enhanced Features */
  63. #define SC16IS7XX_XON1_REG (0x04) /* Xon1 word */
  64. #define SC16IS7XX_XON2_REG (0x05) /* Xon2 word */
  65. #define SC16IS7XX_XOFF1_REG (0x06) /* Xoff1 word */
  66. #define SC16IS7XX_XOFF2_REG (0x07) /* Xoff2 word */
  67. /* IER register bits */
  68. #define SC16IS7XX_IER_RDI_BIT (1 << 0) /* Enable RX data interrupt */
  69. #define SC16IS7XX_IER_THRI_BIT (1 << 1) /* Enable TX holding register
  70. * interrupt */
  71. #define SC16IS7XX_IER_RLSI_BIT (1 << 2) /* Enable RX line status
  72. * interrupt */
  73. #define SC16IS7XX_IER_MSI_BIT (1 << 3) /* Enable Modem status
  74. * interrupt */
  75. /* IER register bits - write only if (EFR[4] == 1) */
  76. #define SC16IS7XX_IER_SLEEP_BIT (1 << 4) /* Enable Sleep mode */
  77. #define SC16IS7XX_IER_XOFFI_BIT (1 << 5) /* Enable Xoff interrupt */
  78. #define SC16IS7XX_IER_RTSI_BIT (1 << 6) /* Enable nRTS interrupt */
  79. #define SC16IS7XX_IER_CTSI_BIT (1 << 7) /* Enable nCTS interrupt */
  80. /* FCR register bits */
  81. #define SC16IS7XX_FCR_FIFO_BIT (1 << 0) /* Enable FIFO */
  82. #define SC16IS7XX_FCR_RXRESET_BIT (1 << 1) /* Reset RX FIFO */
  83. #define SC16IS7XX_FCR_TXRESET_BIT (1 << 2) /* Reset TX FIFO */
  84. #define SC16IS7XX_FCR_RXLVLL_BIT (1 << 6) /* RX Trigger level LSB */
  85. #define SC16IS7XX_FCR_RXLVLH_BIT (1 << 7) /* RX Trigger level MSB */
  86. /* FCR register bits - write only if (EFR[4] == 1) */
  87. #define SC16IS7XX_FCR_TXLVLL_BIT (1 << 4) /* TX Trigger level LSB */
  88. #define SC16IS7XX_FCR_TXLVLH_BIT (1 << 5) /* TX Trigger level MSB */
  89. /* IIR register bits */
  90. #define SC16IS7XX_IIR_NO_INT_BIT (1 << 0) /* No interrupts pending */
  91. #define SC16IS7XX_IIR_ID_MASK 0x3e /* Mask for the interrupt ID */
  92. #define SC16IS7XX_IIR_THRI_SRC 0x02 /* TX holding register empty */
  93. #define SC16IS7XX_IIR_RDI_SRC 0x04 /* RX data interrupt */
  94. #define SC16IS7XX_IIR_RLSE_SRC 0x06 /* RX line status error */
  95. #define SC16IS7XX_IIR_RTOI_SRC 0x0c /* RX time-out interrupt */
  96. #define SC16IS7XX_IIR_MSI_SRC 0x00 /* Modem status interrupt
  97. * - only on 75x/76x
  98. */
  99. #define SC16IS7XX_IIR_INPIN_SRC 0x30 /* Input pin change of state
  100. * - only on 75x/76x
  101. */
  102. #define SC16IS7XX_IIR_XOFFI_SRC 0x10 /* Received Xoff */
  103. #define SC16IS7XX_IIR_CTSRTS_SRC 0x20 /* nCTS,nRTS change of state
  104. * from active (LOW)
  105. * to inactive (HIGH)
  106. */
  107. /* LCR register bits */
  108. #define SC16IS7XX_LCR_LENGTH0_BIT (1 << 0) /* Word length bit 0 */
  109. #define SC16IS7XX_LCR_LENGTH1_BIT (1 << 1) /* Word length bit 1
  110. *
  111. * Word length bits table:
  112. * 00 -> 5 bit words
  113. * 01 -> 6 bit words
  114. * 10 -> 7 bit words
  115. * 11 -> 8 bit words
  116. */
  117. #define SC16IS7XX_LCR_STOPLEN_BIT (1 << 2) /* STOP length bit
  118. *
  119. * STOP length bit table:
  120. * 0 -> 1 stop bit
  121. * 1 -> 1-1.5 stop bits if
  122. * word length is 5,
  123. * 2 stop bits otherwise
  124. */
  125. #define SC16IS7XX_LCR_PARITY_BIT (1 << 3) /* Parity bit enable */
  126. #define SC16IS7XX_LCR_EVENPARITY_BIT (1 << 4) /* Even parity bit enable */
  127. #define SC16IS7XX_LCR_FORCEPARITY_BIT (1 << 5) /* 9-bit multidrop parity */
  128. #define SC16IS7XX_LCR_TXBREAK_BIT (1 << 6) /* TX break enable */
  129. #define SC16IS7XX_LCR_DLAB_BIT (1 << 7) /* Divisor Latch enable */
  130. #define SC16IS7XX_LCR_WORD_LEN_5 (0x00)
  131. #define SC16IS7XX_LCR_WORD_LEN_6 (0x01)
  132. #define SC16IS7XX_LCR_WORD_LEN_7 (0x02)
  133. #define SC16IS7XX_LCR_WORD_LEN_8 (0x03)
  134. #define SC16IS7XX_LCR_CONF_MODE_A SC16IS7XX_LCR_DLAB_BIT /* Special
  135. * reg set */
  136. #define SC16IS7XX_LCR_CONF_MODE_B 0xBF /* Enhanced
  137. * reg set */
  138. /* MCR register bits */
  139. #define SC16IS7XX_MCR_DTR_BIT (1 << 0) /* DTR complement
  140. * - only on 75x/76x
  141. */
  142. #define SC16IS7XX_MCR_RTS_BIT (1 << 1) /* RTS complement */
  143. #define SC16IS7XX_MCR_TCRTLR_BIT (1 << 2) /* TCR/TLR register enable */
  144. #define SC16IS7XX_MCR_LOOP_BIT (1 << 4) /* Enable loopback test mode */
  145. #define SC16IS7XX_MCR_XONANY_BIT (1 << 5) /* Enable Xon Any
  146. * - write enabled
  147. * if (EFR[4] == 1)
  148. */
  149. #define SC16IS7XX_MCR_IRDA_BIT (1 << 6) /* Enable IrDA mode
  150. * - write enabled
  151. * if (EFR[4] == 1)
  152. */
  153. #define SC16IS7XX_MCR_CLKSEL_BIT (1 << 7) /* Divide clock by 4
  154. * - write enabled
  155. * if (EFR[4] == 1)
  156. */
  157. /* LSR register bits */
  158. #define SC16IS7XX_LSR_DR_BIT (1 << 0) /* Receiver data ready */
  159. #define SC16IS7XX_LSR_OE_BIT (1 << 1) /* Overrun Error */
  160. #define SC16IS7XX_LSR_PE_BIT (1 << 2) /* Parity Error */
  161. #define SC16IS7XX_LSR_FE_BIT (1 << 3) /* Frame Error */
  162. #define SC16IS7XX_LSR_BI_BIT (1 << 4) /* Break Interrupt */
  163. #define SC16IS7XX_LSR_BRK_ERROR_MASK 0x1E /* BI, FE, PE, OE bits */
  164. #define SC16IS7XX_LSR_THRE_BIT (1 << 5) /* TX holding register empty */
  165. #define SC16IS7XX_LSR_TEMT_BIT (1 << 6) /* Transmitter empty */
  166. #define SC16IS7XX_LSR_FIFOE_BIT (1 << 7) /* Fifo Error */
  167. /* MSR register bits */
  168. #define SC16IS7XX_MSR_DCTS_BIT (1 << 0) /* Delta CTS Clear To Send */
  169. #define SC16IS7XX_MSR_DDSR_BIT (1 << 1) /* Delta DSR Data Set Ready
  170. * or (IO4)
  171. * - only on 75x/76x
  172. */
  173. #define SC16IS7XX_MSR_DRI_BIT (1 << 2) /* Delta RI Ring Indicator
  174. * or (IO7)
  175. * - only on 75x/76x
  176. */
  177. #define SC16IS7XX_MSR_DCD_BIT (1 << 3) /* Delta CD Carrier Detect
  178. * or (IO6)
  179. * - only on 75x/76x
  180. */
  181. #define SC16IS7XX_MSR_CTS_BIT (1 << 0) /* CTS */
  182. #define SC16IS7XX_MSR_DSR_BIT (1 << 1) /* DSR (IO4)
  183. * - only on 75x/76x
  184. */
  185. #define SC16IS7XX_MSR_RI_BIT (1 << 2) /* RI (IO7)
  186. * - only on 75x/76x
  187. */
  188. #define SC16IS7XX_MSR_CD_BIT (1 << 3) /* CD (IO6)
  189. * - only on 75x/76x
  190. */
  191. #define SC16IS7XX_MSR_DELTA_MASK 0x0F /* Any of the delta bits! */
  192. /*
  193. * TCR register bits
  194. * TCR trigger levels are available from 0 to 60 characters with a granularity
  195. * of four.
  196. * The programmer must program the TCR such that TCR[3:0] > TCR[7:4]. There is
  197. * no built-in hardware check to make sure this condition is met. Also, the TCR
  198. * must be programmed with this condition before auto RTS or software flow
  199. * control is enabled to avoid spurious operation of the device.
  200. */
  201. #define SC16IS7XX_TCR_RX_HALT(words) ((((words) / 4) & 0x0f) << 0)
  202. #define SC16IS7XX_TCR_RX_RESUME(words) ((((words) / 4) & 0x0f) << 4)
  203. /*
  204. * TLR register bits
  205. * If TLR[3:0] or TLR[7:4] are logical 0, the selectable trigger levels via the
  206. * FIFO Control Register (FCR) are used for the transmit and receive FIFO
  207. * trigger levels. Trigger levels from 4 characters to 60 characters are
  208. * available with a granularity of four.
  209. *
  210. * When the trigger level setting in TLR is zero, the SC16IS740/750/760 uses the
  211. * trigger level setting defined in FCR. If TLR has non-zero trigger level value
  212. * the trigger level defined in FCR is discarded. This applies to both transmit
  213. * FIFO and receive FIFO trigger level setting.
  214. *
  215. * When TLR is used for RX trigger level control, FCR[7:6] should be left at the
  216. * default state, that is, '00'.
  217. */
  218. #define SC16IS7XX_TLR_TX_TRIGGER(words) ((((words) / 4) & 0x0f) << 0)
  219. #define SC16IS7XX_TLR_RX_TRIGGER(words) ((((words) / 4) & 0x0f) << 4)
  220. /* IOControl register bits (Only 750/760) */
  221. #define SC16IS7XX_IOCONTROL_LATCH_BIT (1 << 0) /* Enable input latching */
  222. #define SC16IS7XX_IOCONTROL_GPIO_BIT (1 << 1) /* Enable GPIO[7:4] */
  223. #define SC16IS7XX_IOCONTROL_SRESET_BIT (1 << 3) /* Software Reset */
  224. /* EFCR register bits */
  225. #define SC16IS7XX_EFCR_9BIT_MODE_BIT (1 << 0) /* Enable 9-bit or Multidrop
  226. * mode (RS485) */
  227. #define SC16IS7XX_EFCR_RXDISABLE_BIT (1 << 1) /* Disable receiver */
  228. #define SC16IS7XX_EFCR_TXDISABLE_BIT (1 << 2) /* Disable transmitter */
  229. #define SC16IS7XX_EFCR_AUTO_RS485_BIT (1 << 4) /* Auto RS485 RTS direction */
  230. #define SC16IS7XX_EFCR_RTS_INVERT_BIT (1 << 5) /* RTS output inversion */
  231. #define SC16IS7XX_EFCR_IRDA_MODE_BIT (1 << 7) /* IrDA mode
  232. * 0 = rate upto 115.2 kbit/s
  233. * - Only 750/760
  234. * 1 = rate upto 1.152 Mbit/s
  235. * - Only 760
  236. */
  237. /* EFR register bits */
  238. #define SC16IS7XX_EFR_AUTORTS_BIT (1 << 6) /* Auto RTS flow ctrl enable */
  239. #define SC16IS7XX_EFR_AUTOCTS_BIT (1 << 7) /* Auto CTS flow ctrl enable */
  240. #define SC16IS7XX_EFR_XOFF2_DETECT_BIT (1 << 5) /* Enable Xoff2 detection */
  241. #define SC16IS7XX_EFR_ENABLE_BIT (1 << 4) /* Enable enhanced functions
  242. * and writing to IER[7:4],
  243. * FCR[5:4], MCR[7:5]
  244. */
  245. #define SC16IS7XX_EFR_SWFLOW3_BIT (1 << 3) /* SWFLOW bit 3 */
  246. #define SC16IS7XX_EFR_SWFLOW2_BIT (1 << 2) /* SWFLOW bit 2
  247. *
  248. * SWFLOW bits 3 & 2 table:
  249. * 00 -> no transmitter flow
  250. * control
  251. * 01 -> transmitter generates
  252. * XON2 and XOFF2
  253. * 10 -> transmitter generates
  254. * XON1 and XOFF1
  255. * 11 -> transmitter generates
  256. * XON1, XON2, XOFF1 and
  257. * XOFF2
  258. */
  259. #define SC16IS7XX_EFR_SWFLOW1_BIT (1 << 1) /* SWFLOW bit 2 */
  260. #define SC16IS7XX_EFR_SWFLOW0_BIT (1 << 0) /* SWFLOW bit 3
  261. *
  262. * SWFLOW bits 3 & 2 table:
  263. * 00 -> no received flow
  264. * control
  265. * 01 -> receiver compares
  266. * XON2 and XOFF2
  267. * 10 -> receiver compares
  268. * XON1 and XOFF1
  269. * 11 -> receiver compares
  270. * XON1, XON2, XOFF1 and
  271. * XOFF2
  272. */
  273. /* Misc definitions */
  274. #define SC16IS7XX_FIFO_SIZE (64)
  275. #define SC16IS7XX_REG_SHIFT 2
  276. struct sc16is7xx_devtype {
  277. char name[10];
  278. int nr_gpio;
  279. int nr_uart;
  280. };
  281. struct sc16is7xx_one {
  282. struct uart_port port;
  283. struct work_struct tx_work;
  284. struct work_struct md_work;
  285. };
  286. struct sc16is7xx_port {
  287. struct uart_driver uart;
  288. struct sc16is7xx_devtype *devtype;
  289. struct regmap *regmap;
  290. struct mutex mutex;
  291. struct clk *clk;
  292. #ifdef CONFIG_GPIOLIB
  293. struct gpio_chip gpio;
  294. #endif
  295. unsigned char buf[SC16IS7XX_FIFO_SIZE];
  296. struct sc16is7xx_one p[0];
  297. };
  298. #define to_sc16is7xx_one(p,e) ((container_of((p), struct sc16is7xx_one, e)))
  299. static u8 sc16is7xx_port_read(struct uart_port *port, u8 reg)
  300. {
  301. struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
  302. unsigned int val = 0;
  303. regmap_read(s->regmap,
  304. (reg << SC16IS7XX_REG_SHIFT) | port->line, &val);
  305. return val;
  306. }
  307. static void sc16is7xx_port_write(struct uart_port *port, u8 reg, u8 val)
  308. {
  309. struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
  310. regmap_write(s->regmap,
  311. (reg << SC16IS7XX_REG_SHIFT) | port->line, val);
  312. }
  313. static void sc16is7xx_port_update(struct uart_port *port, u8 reg,
  314. u8 mask, u8 val)
  315. {
  316. struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
  317. regmap_update_bits(s->regmap,
  318. (reg << SC16IS7XX_REG_SHIFT) | port->line,
  319. mask, val);
  320. }
  321. static void sc16is7xx_power(struct uart_port *port, int on)
  322. {
  323. sc16is7xx_port_update(port, SC16IS7XX_IER_REG,
  324. SC16IS7XX_IER_SLEEP_BIT,
  325. on ? 0 : SC16IS7XX_IER_SLEEP_BIT);
  326. }
  327. static const struct sc16is7xx_devtype sc16is74x_devtype = {
  328. .name = "SC16IS74X",
  329. .nr_gpio = 0,
  330. .nr_uart = 1,
  331. };
  332. static const struct sc16is7xx_devtype sc16is750_devtype = {
  333. .name = "SC16IS750",
  334. .nr_gpio = 8,
  335. .nr_uart = 1,
  336. };
  337. static const struct sc16is7xx_devtype sc16is752_devtype = {
  338. .name = "SC16IS752",
  339. .nr_gpio = 8,
  340. .nr_uart = 2,
  341. };
  342. static const struct sc16is7xx_devtype sc16is760_devtype = {
  343. .name = "SC16IS760",
  344. .nr_gpio = 8,
  345. .nr_uart = 1,
  346. };
  347. static const struct sc16is7xx_devtype sc16is762_devtype = {
  348. .name = "SC16IS762",
  349. .nr_gpio = 8,
  350. .nr_uart = 2,
  351. };
  352. static bool sc16is7xx_regmap_volatile(struct device *dev, unsigned int reg)
  353. {
  354. switch (reg >> SC16IS7XX_REG_SHIFT) {
  355. case SC16IS7XX_RHR_REG:
  356. case SC16IS7XX_IIR_REG:
  357. case SC16IS7XX_LSR_REG:
  358. case SC16IS7XX_MSR_REG:
  359. case SC16IS7XX_TXLVL_REG:
  360. case SC16IS7XX_RXLVL_REG:
  361. case SC16IS7XX_IOSTATE_REG:
  362. return true;
  363. default:
  364. break;
  365. }
  366. return false;
  367. }
  368. static bool sc16is7xx_regmap_precious(struct device *dev, unsigned int reg)
  369. {
  370. switch (reg >> SC16IS7XX_REG_SHIFT) {
  371. case SC16IS7XX_RHR_REG:
  372. return true;
  373. default:
  374. break;
  375. }
  376. return false;
  377. }
  378. static int sc16is7xx_set_baud(struct uart_port *port, int baud)
  379. {
  380. struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
  381. u8 lcr;
  382. u8 prescaler = 0;
  383. unsigned long clk = port->uartclk, div = clk / 16 / baud;
  384. if (div > 0xffff) {
  385. prescaler = SC16IS7XX_MCR_CLKSEL_BIT;
  386. div /= 4;
  387. }
  388. lcr = sc16is7xx_port_read(port, SC16IS7XX_LCR_REG);
  389. /* Open the LCR divisors for configuration */
  390. sc16is7xx_port_write(port, SC16IS7XX_LCR_REG,
  391. SC16IS7XX_LCR_CONF_MODE_B);
  392. /* Enable enhanced features */
  393. regcache_cache_bypass(s->regmap, true);
  394. sc16is7xx_port_write(port, SC16IS7XX_EFR_REG,
  395. SC16IS7XX_EFR_ENABLE_BIT);
  396. regcache_cache_bypass(s->regmap, false);
  397. /* Put LCR back to the normal mode */
  398. sc16is7xx_port_write(port, SC16IS7XX_LCR_REG, lcr);
  399. sc16is7xx_port_update(port, SC16IS7XX_MCR_REG,
  400. SC16IS7XX_MCR_CLKSEL_BIT,
  401. prescaler);
  402. /* Open the LCR divisors for configuration */
  403. sc16is7xx_port_write(port, SC16IS7XX_LCR_REG,
  404. SC16IS7XX_LCR_CONF_MODE_A);
  405. /* Write the new divisor */
  406. regcache_cache_bypass(s->regmap, true);
  407. sc16is7xx_port_write(port, SC16IS7XX_DLH_REG, div / 256);
  408. sc16is7xx_port_write(port, SC16IS7XX_DLL_REG, div % 256);
  409. regcache_cache_bypass(s->regmap, false);
  410. /* Put LCR back to the normal mode */
  411. sc16is7xx_port_write(port, SC16IS7XX_LCR_REG, lcr);
  412. return DIV_ROUND_CLOSEST(clk / 16, div);
  413. }
  414. static void sc16is7xx_handle_rx(struct uart_port *port, unsigned int rxlen,
  415. unsigned int iir)
  416. {
  417. struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
  418. unsigned int lsr = 0, ch, flag, bytes_read, i;
  419. bool read_lsr = (iir == SC16IS7XX_IIR_RLSE_SRC) ? true : false;
  420. if (unlikely(rxlen >= sizeof(s->buf))) {
  421. dev_warn_ratelimited(port->dev,
  422. "Port %i: Possible RX FIFO overrun: %d\n",
  423. port->line, rxlen);
  424. port->icount.buf_overrun++;
  425. /* Ensure sanity of RX level */
  426. rxlen = sizeof(s->buf);
  427. }
  428. while (rxlen) {
  429. /* Only read lsr if there are possible errors in FIFO */
  430. if (read_lsr) {
  431. lsr = sc16is7xx_port_read(port, SC16IS7XX_LSR_REG);
  432. if (!(lsr & SC16IS7XX_LSR_FIFOE_BIT))
  433. read_lsr = false; /* No errors left in FIFO */
  434. } else
  435. lsr = 0;
  436. if (read_lsr) {
  437. s->buf[0] = sc16is7xx_port_read(port, SC16IS7XX_RHR_REG);
  438. bytes_read = 1;
  439. } else {
  440. regcache_cache_bypass(s->regmap, true);
  441. regmap_raw_read(s->regmap, SC16IS7XX_RHR_REG,
  442. s->buf, rxlen);
  443. regcache_cache_bypass(s->regmap, false);
  444. bytes_read = rxlen;
  445. }
  446. lsr &= SC16IS7XX_LSR_BRK_ERROR_MASK;
  447. port->icount.rx++;
  448. flag = TTY_NORMAL;
  449. if (unlikely(lsr)) {
  450. if (lsr & SC16IS7XX_LSR_BI_BIT) {
  451. port->icount.brk++;
  452. if (uart_handle_break(port))
  453. continue;
  454. } else if (lsr & SC16IS7XX_LSR_PE_BIT)
  455. port->icount.parity++;
  456. else if (lsr & SC16IS7XX_LSR_FE_BIT)
  457. port->icount.frame++;
  458. else if (lsr & SC16IS7XX_LSR_OE_BIT)
  459. port->icount.overrun++;
  460. lsr &= port->read_status_mask;
  461. if (lsr & SC16IS7XX_LSR_BI_BIT)
  462. flag = TTY_BREAK;
  463. else if (lsr & SC16IS7XX_LSR_PE_BIT)
  464. flag = TTY_PARITY;
  465. else if (lsr & SC16IS7XX_LSR_FE_BIT)
  466. flag = TTY_FRAME;
  467. else if (lsr & SC16IS7XX_LSR_OE_BIT)
  468. flag = TTY_OVERRUN;
  469. }
  470. for (i = 0; i < bytes_read; ++i) {
  471. ch = s->buf[i];
  472. if (uart_handle_sysrq_char(port, ch))
  473. continue;
  474. if (lsr & port->ignore_status_mask)
  475. continue;
  476. uart_insert_char(port, lsr, SC16IS7XX_LSR_OE_BIT, ch,
  477. flag);
  478. }
  479. rxlen -= bytes_read;
  480. }
  481. tty_flip_buffer_push(&port->state->port);
  482. }
  483. static void sc16is7xx_handle_tx(struct uart_port *port)
  484. {
  485. struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
  486. struct circ_buf *xmit = &port->state->xmit;
  487. unsigned int txlen, to_send, i;
  488. if (unlikely(port->x_char)) {
  489. sc16is7xx_port_write(port, SC16IS7XX_THR_REG, port->x_char);
  490. port->icount.tx++;
  491. port->x_char = 0;
  492. return;
  493. }
  494. if (uart_circ_empty(xmit) || uart_tx_stopped(port))
  495. return;
  496. /* Get length of data pending in circular buffer */
  497. to_send = uart_circ_chars_pending(xmit);
  498. if (likely(to_send)) {
  499. /* Limit to size of TX FIFO */
  500. txlen = sc16is7xx_port_read(port, SC16IS7XX_TXLVL_REG);
  501. to_send = (to_send > txlen) ? txlen : to_send;
  502. /* Add data to send */
  503. port->icount.tx += to_send;
  504. /* Convert to linear buffer */
  505. for (i = 0; i < to_send; ++i) {
  506. s->buf[i] = xmit->buf[xmit->tail];
  507. xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
  508. }
  509. regcache_cache_bypass(s->regmap, true);
  510. regmap_raw_write(s->regmap, SC16IS7XX_THR_REG, s->buf, to_send);
  511. regcache_cache_bypass(s->regmap, false);
  512. }
  513. if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
  514. uart_write_wakeup(port);
  515. }
  516. static void sc16is7xx_port_irq(struct sc16is7xx_port *s, int portno)
  517. {
  518. struct uart_port *port = &s->p[portno].port;
  519. do {
  520. unsigned int iir, msr, rxlen;
  521. iir = sc16is7xx_port_read(port, SC16IS7XX_IIR_REG);
  522. if (iir & SC16IS7XX_IIR_NO_INT_BIT)
  523. break;
  524. iir &= SC16IS7XX_IIR_ID_MASK;
  525. switch (iir) {
  526. case SC16IS7XX_IIR_RDI_SRC:
  527. case SC16IS7XX_IIR_RLSE_SRC:
  528. case SC16IS7XX_IIR_RTOI_SRC:
  529. case SC16IS7XX_IIR_XOFFI_SRC:
  530. rxlen = sc16is7xx_port_read(port, SC16IS7XX_RXLVL_REG);
  531. if (rxlen)
  532. sc16is7xx_handle_rx(port, rxlen, iir);
  533. break;
  534. case SC16IS7XX_IIR_CTSRTS_SRC:
  535. msr = sc16is7xx_port_read(port, SC16IS7XX_MSR_REG);
  536. uart_handle_cts_change(port,
  537. !!(msr & SC16IS7XX_MSR_CTS_BIT));
  538. break;
  539. case SC16IS7XX_IIR_THRI_SRC:
  540. mutex_lock(&s->mutex);
  541. sc16is7xx_handle_tx(port);
  542. mutex_unlock(&s->mutex);
  543. break;
  544. default:
  545. dev_err_ratelimited(port->dev,
  546. "Port %i: Unexpected interrupt: %x",
  547. port->line, iir);
  548. break;
  549. }
  550. } while (1);
  551. }
  552. static irqreturn_t sc16is7xx_ist(int irq, void *dev_id)
  553. {
  554. struct sc16is7xx_port *s = (struct sc16is7xx_port *)dev_id;
  555. int i;
  556. for (i = 0; i < s->uart.nr; ++i)
  557. sc16is7xx_port_irq(s, i);
  558. return IRQ_HANDLED;
  559. }
  560. static void sc16is7xx_wq_proc(struct work_struct *ws)
  561. {
  562. struct sc16is7xx_one *one = to_sc16is7xx_one(ws, tx_work);
  563. struct sc16is7xx_port *s = dev_get_drvdata(one->port.dev);
  564. mutex_lock(&s->mutex);
  565. sc16is7xx_handle_tx(&one->port);
  566. mutex_unlock(&s->mutex);
  567. }
  568. static void sc16is7xx_stop_tx(struct uart_port* port)
  569. {
  570. struct sc16is7xx_one *one = to_sc16is7xx_one(port, port);
  571. struct circ_buf *xmit = &one->port.state->xmit;
  572. /* handle rs485 */
  573. if (port->rs485.flags & SER_RS485_ENABLED) {
  574. /* do nothing if current tx not yet completed */
  575. int lsr = sc16is7xx_port_read(port, SC16IS7XX_LSR_REG);
  576. if (!(lsr & SC16IS7XX_LSR_TEMT_BIT))
  577. return;
  578. if (uart_circ_empty(xmit) &&
  579. (port->rs485.delay_rts_after_send > 0))
  580. mdelay(port->rs485.delay_rts_after_send);
  581. }
  582. sc16is7xx_port_update(port, SC16IS7XX_IER_REG,
  583. SC16IS7XX_IER_THRI_BIT,
  584. 0);
  585. }
  586. static void sc16is7xx_stop_rx(struct uart_port* port)
  587. {
  588. struct sc16is7xx_one *one = to_sc16is7xx_one(port, port);
  589. one->port.read_status_mask &= ~SC16IS7XX_LSR_DR_BIT;
  590. sc16is7xx_port_update(port, SC16IS7XX_IER_REG,
  591. SC16IS7XX_LSR_DR_BIT,
  592. 0);
  593. }
  594. static void sc16is7xx_start_tx(struct uart_port *port)
  595. {
  596. struct sc16is7xx_one *one = to_sc16is7xx_one(port, port);
  597. /* handle rs485 */
  598. if ((port->rs485.flags & SER_RS485_ENABLED) &&
  599. (port->rs485.delay_rts_before_send > 0)) {
  600. mdelay(port->rs485.delay_rts_before_send);
  601. }
  602. if (!work_pending(&one->tx_work))
  603. schedule_work(&one->tx_work);
  604. }
  605. static unsigned int sc16is7xx_tx_empty(struct uart_port *port)
  606. {
  607. unsigned int lvl, lsr;
  608. lvl = sc16is7xx_port_read(port, SC16IS7XX_TXLVL_REG);
  609. lsr = sc16is7xx_port_read(port, SC16IS7XX_LSR_REG);
  610. return ((lsr & SC16IS7XX_LSR_THRE_BIT) && !lvl) ? TIOCSER_TEMT : 0;
  611. }
  612. static unsigned int sc16is7xx_get_mctrl(struct uart_port *port)
  613. {
  614. /* DCD and DSR are not wired and CTS/RTS is handled automatically
  615. * so just indicate DSR and CAR asserted
  616. */
  617. return TIOCM_DSR | TIOCM_CAR;
  618. }
  619. static void sc16is7xx_md_proc(struct work_struct *ws)
  620. {
  621. struct sc16is7xx_one *one = to_sc16is7xx_one(ws, md_work);
  622. sc16is7xx_port_update(&one->port, SC16IS7XX_MCR_REG,
  623. SC16IS7XX_MCR_LOOP_BIT,
  624. (one->port.mctrl & TIOCM_LOOP) ?
  625. SC16IS7XX_MCR_LOOP_BIT : 0);
  626. }
  627. static void sc16is7xx_set_mctrl(struct uart_port *port, unsigned int mctrl)
  628. {
  629. struct sc16is7xx_one *one = to_sc16is7xx_one(port, port);
  630. schedule_work(&one->md_work);
  631. }
  632. static void sc16is7xx_break_ctl(struct uart_port *port, int break_state)
  633. {
  634. sc16is7xx_port_update(port, SC16IS7XX_LCR_REG,
  635. SC16IS7XX_LCR_TXBREAK_BIT,
  636. break_state ? SC16IS7XX_LCR_TXBREAK_BIT : 0);
  637. }
  638. static void sc16is7xx_set_termios(struct uart_port *port,
  639. struct ktermios *termios,
  640. struct ktermios *old)
  641. {
  642. struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
  643. unsigned int lcr, flow = 0;
  644. int baud;
  645. /* Mask termios capabilities we don't support */
  646. termios->c_cflag &= ~CMSPAR;
  647. /* Word size */
  648. switch (termios->c_cflag & CSIZE) {
  649. case CS5:
  650. lcr = SC16IS7XX_LCR_WORD_LEN_5;
  651. break;
  652. case CS6:
  653. lcr = SC16IS7XX_LCR_WORD_LEN_6;
  654. break;
  655. case CS7:
  656. lcr = SC16IS7XX_LCR_WORD_LEN_7;
  657. break;
  658. case CS8:
  659. lcr = SC16IS7XX_LCR_WORD_LEN_8;
  660. break;
  661. default:
  662. lcr = SC16IS7XX_LCR_WORD_LEN_8;
  663. termios->c_cflag &= ~CSIZE;
  664. termios->c_cflag |= CS8;
  665. break;
  666. }
  667. /* Parity */
  668. if (termios->c_cflag & PARENB) {
  669. lcr |= SC16IS7XX_LCR_PARITY_BIT;
  670. if (!(termios->c_cflag & PARODD))
  671. lcr |= SC16IS7XX_LCR_EVENPARITY_BIT;
  672. }
  673. /* Stop bits */
  674. if (termios->c_cflag & CSTOPB)
  675. lcr |= SC16IS7XX_LCR_STOPLEN_BIT; /* 2 stops */
  676. /* Set read status mask */
  677. port->read_status_mask = SC16IS7XX_LSR_OE_BIT;
  678. if (termios->c_iflag & INPCK)
  679. port->read_status_mask |= SC16IS7XX_LSR_PE_BIT |
  680. SC16IS7XX_LSR_FE_BIT;
  681. if (termios->c_iflag & (BRKINT | PARMRK))
  682. port->read_status_mask |= SC16IS7XX_LSR_BI_BIT;
  683. /* Set status ignore mask */
  684. port->ignore_status_mask = 0;
  685. if (termios->c_iflag & IGNBRK)
  686. port->ignore_status_mask |= SC16IS7XX_LSR_BI_BIT;
  687. if (!(termios->c_cflag & CREAD))
  688. port->ignore_status_mask |= SC16IS7XX_LSR_BRK_ERROR_MASK;
  689. sc16is7xx_port_write(port, SC16IS7XX_LCR_REG,
  690. SC16IS7XX_LCR_CONF_MODE_B);
  691. /* Configure flow control */
  692. regcache_cache_bypass(s->regmap, true);
  693. sc16is7xx_port_write(port, SC16IS7XX_XON1_REG, termios->c_cc[VSTART]);
  694. sc16is7xx_port_write(port, SC16IS7XX_XOFF1_REG, termios->c_cc[VSTOP]);
  695. if (termios->c_cflag & CRTSCTS)
  696. flow |= SC16IS7XX_EFR_AUTOCTS_BIT |
  697. SC16IS7XX_EFR_AUTORTS_BIT;
  698. if (termios->c_iflag & IXON)
  699. flow |= SC16IS7XX_EFR_SWFLOW3_BIT;
  700. if (termios->c_iflag & IXOFF)
  701. flow |= SC16IS7XX_EFR_SWFLOW1_BIT;
  702. sc16is7xx_port_write(port, SC16IS7XX_EFR_REG, flow);
  703. regcache_cache_bypass(s->regmap, false);
  704. /* Update LCR register */
  705. sc16is7xx_port_write(port, SC16IS7XX_LCR_REG, lcr);
  706. /* Get baud rate generator configuration */
  707. baud = uart_get_baud_rate(port, termios, old,
  708. port->uartclk / 16 / 4 / 0xffff,
  709. port->uartclk / 16);
  710. /* Setup baudrate generator */
  711. baud = sc16is7xx_set_baud(port, baud);
  712. /* Update timeout according to new baud rate */
  713. uart_update_timeout(port, termios->c_cflag, baud);
  714. }
  715. static int sc16is7xx_config_rs485(struct uart_port *port,
  716. struct serial_rs485 *rs485)
  717. {
  718. if (port->rs485.flags & SER_RS485_ENABLED)
  719. sc16is7xx_port_update(port, SC16IS7XX_EFCR_REG,
  720. SC16IS7XX_EFCR_AUTO_RS485_BIT,
  721. SC16IS7XX_EFCR_AUTO_RS485_BIT);
  722. else
  723. sc16is7xx_port_update(port, SC16IS7XX_EFCR_REG,
  724. SC16IS7XX_EFCR_AUTO_RS485_BIT,
  725. 0);
  726. port->rs485 = *rs485;
  727. return 0;
  728. }
  729. static int sc16is7xx_startup(struct uart_port *port)
  730. {
  731. struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
  732. unsigned int val;
  733. sc16is7xx_power(port, 1);
  734. /* Reset FIFOs*/
  735. val = SC16IS7XX_FCR_RXRESET_BIT | SC16IS7XX_FCR_TXRESET_BIT;
  736. sc16is7xx_port_write(port, SC16IS7XX_FCR_REG, val);
  737. udelay(5);
  738. sc16is7xx_port_write(port, SC16IS7XX_FCR_REG,
  739. SC16IS7XX_FCR_FIFO_BIT);
  740. /* Enable EFR */
  741. sc16is7xx_port_write(port, SC16IS7XX_LCR_REG,
  742. SC16IS7XX_LCR_CONF_MODE_B);
  743. regcache_cache_bypass(s->regmap, true);
  744. /* Enable write access to enhanced features and internal clock div */
  745. sc16is7xx_port_write(port, SC16IS7XX_EFR_REG,
  746. SC16IS7XX_EFR_ENABLE_BIT);
  747. /* Enable TCR/TLR */
  748. sc16is7xx_port_update(port, SC16IS7XX_MCR_REG,
  749. SC16IS7XX_MCR_TCRTLR_BIT,
  750. SC16IS7XX_MCR_TCRTLR_BIT);
  751. /* Configure flow control levels */
  752. /* Flow control halt level 48, resume level 24 */
  753. sc16is7xx_port_write(port, SC16IS7XX_TCR_REG,
  754. SC16IS7XX_TCR_RX_RESUME(24) |
  755. SC16IS7XX_TCR_RX_HALT(48));
  756. regcache_cache_bypass(s->regmap, false);
  757. /* Now, initialize the UART */
  758. sc16is7xx_port_write(port, SC16IS7XX_LCR_REG, SC16IS7XX_LCR_WORD_LEN_8);
  759. /* Enable the Rx and Tx FIFO */
  760. sc16is7xx_port_update(port, SC16IS7XX_EFCR_REG,
  761. SC16IS7XX_EFCR_RXDISABLE_BIT |
  762. SC16IS7XX_EFCR_TXDISABLE_BIT,
  763. 0);
  764. /* Enable RX, TX, CTS change interrupts */
  765. val = SC16IS7XX_IER_RDI_BIT | SC16IS7XX_IER_THRI_BIT |
  766. SC16IS7XX_IER_CTSI_BIT;
  767. sc16is7xx_port_write(port, SC16IS7XX_IER_REG, val);
  768. return 0;
  769. }
  770. static void sc16is7xx_shutdown(struct uart_port *port)
  771. {
  772. /* Disable all interrupts */
  773. sc16is7xx_port_write(port, SC16IS7XX_IER_REG, 0);
  774. /* Disable TX/RX */
  775. sc16is7xx_port_write(port, SC16IS7XX_EFCR_REG,
  776. SC16IS7XX_EFCR_RXDISABLE_BIT |
  777. SC16IS7XX_EFCR_TXDISABLE_BIT);
  778. sc16is7xx_power(port, 0);
  779. }
  780. static const char *sc16is7xx_type(struct uart_port *port)
  781. {
  782. struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
  783. return (port->type == PORT_SC16IS7XX) ? s->devtype->name : NULL;
  784. }
  785. static int sc16is7xx_request_port(struct uart_port *port)
  786. {
  787. /* Do nothing */
  788. return 0;
  789. }
  790. static void sc16is7xx_config_port(struct uart_port *port, int flags)
  791. {
  792. if (flags & UART_CONFIG_TYPE)
  793. port->type = PORT_SC16IS7XX;
  794. }
  795. static int sc16is7xx_verify_port(struct uart_port *port,
  796. struct serial_struct *s)
  797. {
  798. if ((s->type != PORT_UNKNOWN) && (s->type != PORT_SC16IS7XX))
  799. return -EINVAL;
  800. if (s->irq != port->irq)
  801. return -EINVAL;
  802. return 0;
  803. }
  804. static void sc16is7xx_pm(struct uart_port *port, unsigned int state,
  805. unsigned int oldstate)
  806. {
  807. sc16is7xx_power(port, (state == UART_PM_STATE_ON) ? 1 : 0);
  808. }
  809. static void sc16is7xx_null_void(struct uart_port *port)
  810. {
  811. /* Do nothing */
  812. }
  813. static const struct uart_ops sc16is7xx_ops = {
  814. .tx_empty = sc16is7xx_tx_empty,
  815. .set_mctrl = sc16is7xx_set_mctrl,
  816. .get_mctrl = sc16is7xx_get_mctrl,
  817. .stop_tx = sc16is7xx_stop_tx,
  818. .start_tx = sc16is7xx_start_tx,
  819. .stop_rx = sc16is7xx_stop_rx,
  820. .break_ctl = sc16is7xx_break_ctl,
  821. .startup = sc16is7xx_startup,
  822. .shutdown = sc16is7xx_shutdown,
  823. .set_termios = sc16is7xx_set_termios,
  824. .type = sc16is7xx_type,
  825. .request_port = sc16is7xx_request_port,
  826. .release_port = sc16is7xx_null_void,
  827. .config_port = sc16is7xx_config_port,
  828. .verify_port = sc16is7xx_verify_port,
  829. .pm = sc16is7xx_pm,
  830. };
  831. #ifdef CONFIG_GPIOLIB
  832. static int sc16is7xx_gpio_get(struct gpio_chip *chip, unsigned offset)
  833. {
  834. unsigned int val;
  835. struct sc16is7xx_port *s = container_of(chip, struct sc16is7xx_port,
  836. gpio);
  837. struct uart_port *port = &s->p[0].port;
  838. val = sc16is7xx_port_read(port, SC16IS7XX_IOSTATE_REG);
  839. return !!(val & BIT(offset));
  840. }
  841. static void sc16is7xx_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
  842. {
  843. struct sc16is7xx_port *s = container_of(chip, struct sc16is7xx_port,
  844. gpio);
  845. struct uart_port *port = &s->p[0].port;
  846. sc16is7xx_port_update(port, SC16IS7XX_IOSTATE_REG, BIT(offset),
  847. val ? BIT(offset) : 0);
  848. }
  849. static int sc16is7xx_gpio_direction_input(struct gpio_chip *chip,
  850. unsigned offset)
  851. {
  852. struct sc16is7xx_port *s = container_of(chip, struct sc16is7xx_port,
  853. gpio);
  854. struct uart_port *port = &s->p[0].port;
  855. sc16is7xx_port_update(port, SC16IS7XX_IODIR_REG, BIT(offset), 0);
  856. return 0;
  857. }
  858. static int sc16is7xx_gpio_direction_output(struct gpio_chip *chip,
  859. unsigned offset, int val)
  860. {
  861. struct sc16is7xx_port *s = container_of(chip, struct sc16is7xx_port,
  862. gpio);
  863. struct uart_port *port = &s->p[0].port;
  864. sc16is7xx_port_update(port, SC16IS7XX_IOSTATE_REG, BIT(offset),
  865. val ? BIT(offset) : 0);
  866. sc16is7xx_port_update(port, SC16IS7XX_IODIR_REG, BIT(offset),
  867. BIT(offset));
  868. return 0;
  869. }
  870. #endif
  871. static int sc16is7xx_probe(struct device *dev,
  872. struct sc16is7xx_devtype *devtype,
  873. struct regmap *regmap, int irq, unsigned long flags)
  874. {
  875. unsigned long freq, *pfreq = dev_get_platdata(dev);
  876. int i, ret;
  877. struct sc16is7xx_port *s;
  878. if (IS_ERR(regmap))
  879. return PTR_ERR(regmap);
  880. /* Alloc port structure */
  881. s = devm_kzalloc(dev, sizeof(*s) +
  882. sizeof(struct sc16is7xx_one) * devtype->nr_uart,
  883. GFP_KERNEL);
  884. if (!s) {
  885. dev_err(dev, "Error allocating port structure\n");
  886. return -ENOMEM;
  887. }
  888. s->clk = devm_clk_get(dev, NULL);
  889. if (IS_ERR(s->clk)) {
  890. if (pfreq)
  891. freq = *pfreq;
  892. else
  893. return PTR_ERR(s->clk);
  894. } else {
  895. freq = clk_get_rate(s->clk);
  896. }
  897. s->regmap = regmap;
  898. s->devtype = devtype;
  899. dev_set_drvdata(dev, s);
  900. /* Register UART driver */
  901. s->uart.owner = THIS_MODULE;
  902. s->uart.dev_name = "ttySC";
  903. s->uart.nr = devtype->nr_uart;
  904. ret = uart_register_driver(&s->uart);
  905. if (ret) {
  906. dev_err(dev, "Registering UART driver failed\n");
  907. goto out_clk;
  908. }
  909. #ifdef CONFIG_GPIOLIB
  910. if (devtype->nr_gpio) {
  911. /* Setup GPIO cotroller */
  912. s->gpio.owner = THIS_MODULE;
  913. s->gpio.dev = dev;
  914. s->gpio.label = dev_name(dev);
  915. s->gpio.direction_input = sc16is7xx_gpio_direction_input;
  916. s->gpio.get = sc16is7xx_gpio_get;
  917. s->gpio.direction_output = sc16is7xx_gpio_direction_output;
  918. s->gpio.set = sc16is7xx_gpio_set;
  919. s->gpio.base = -1;
  920. s->gpio.ngpio = devtype->nr_gpio;
  921. s->gpio.can_sleep = 1;
  922. ret = gpiochip_add(&s->gpio);
  923. if (ret)
  924. goto out_uart;
  925. }
  926. #endif
  927. mutex_init(&s->mutex);
  928. for (i = 0; i < devtype->nr_uart; ++i) {
  929. /* Initialize port data */
  930. s->p[i].port.line = i;
  931. s->p[i].port.dev = dev;
  932. s->p[i].port.irq = irq;
  933. s->p[i].port.type = PORT_SC16IS7XX;
  934. s->p[i].port.fifosize = SC16IS7XX_FIFO_SIZE;
  935. s->p[i].port.flags = UPF_FIXED_TYPE | UPF_LOW_LATENCY;
  936. s->p[i].port.iotype = UPIO_PORT;
  937. s->p[i].port.uartclk = freq;
  938. s->p[i].port.rs485_config = sc16is7xx_config_rs485;
  939. s->p[i].port.ops = &sc16is7xx_ops;
  940. /* Disable all interrupts */
  941. sc16is7xx_port_write(&s->p[i].port, SC16IS7XX_IER_REG, 0);
  942. /* Disable TX/RX */
  943. sc16is7xx_port_write(&s->p[i].port, SC16IS7XX_EFCR_REG,
  944. SC16IS7XX_EFCR_RXDISABLE_BIT |
  945. SC16IS7XX_EFCR_TXDISABLE_BIT);
  946. /* Initialize queue for start TX */
  947. INIT_WORK(&s->p[i].tx_work, sc16is7xx_wq_proc);
  948. /* Initialize queue for changing mode */
  949. INIT_WORK(&s->p[i].md_work, sc16is7xx_md_proc);
  950. /* Register port */
  951. uart_add_one_port(&s->uart, &s->p[i].port);
  952. /* Go to suspend mode */
  953. sc16is7xx_power(&s->p[i].port, 0);
  954. }
  955. /* Setup interrupt */
  956. ret = devm_request_threaded_irq(dev, irq, NULL, sc16is7xx_ist,
  957. IRQF_ONESHOT | flags, dev_name(dev), s);
  958. if (!ret)
  959. return 0;
  960. mutex_destroy(&s->mutex);
  961. #ifdef CONFIG_GPIOLIB
  962. if (devtype->nr_gpio)
  963. gpiochip_remove(&s->gpio);
  964. out_uart:
  965. #endif
  966. uart_unregister_driver(&s->uart);
  967. out_clk:
  968. if (!IS_ERR(s->clk))
  969. clk_disable_unprepare(s->clk);
  970. return ret;
  971. }
  972. static int sc16is7xx_remove(struct device *dev)
  973. {
  974. struct sc16is7xx_port *s = dev_get_drvdata(dev);
  975. int i;
  976. #ifdef CONFIG_GPIOLIB
  977. if (s->devtype->nr_gpio)
  978. gpiochip_remove(&s->gpio);
  979. #endif
  980. for (i = 0; i < s->uart.nr; i++) {
  981. cancel_work_sync(&s->p[i].tx_work);
  982. cancel_work_sync(&s->p[i].md_work);
  983. uart_remove_one_port(&s->uart, &s->p[i].port);
  984. sc16is7xx_power(&s->p[i].port, 0);
  985. }
  986. mutex_destroy(&s->mutex);
  987. uart_unregister_driver(&s->uart);
  988. if (!IS_ERR(s->clk))
  989. clk_disable_unprepare(s->clk);
  990. return 0;
  991. }
  992. static const struct of_device_id __maybe_unused sc16is7xx_dt_ids[] = {
  993. { .compatible = "nxp,sc16is740", .data = &sc16is74x_devtype, },
  994. { .compatible = "nxp,sc16is741", .data = &sc16is74x_devtype, },
  995. { .compatible = "nxp,sc16is750", .data = &sc16is750_devtype, },
  996. { .compatible = "nxp,sc16is752", .data = &sc16is752_devtype, },
  997. { .compatible = "nxp,sc16is760", .data = &sc16is760_devtype, },
  998. { .compatible = "nxp,sc16is762", .data = &sc16is762_devtype, },
  999. { }
  1000. };
  1001. MODULE_DEVICE_TABLE(of, sc16is7xx_dt_ids);
  1002. static struct regmap_config regcfg = {
  1003. .reg_bits = 7,
  1004. .pad_bits = 1,
  1005. .val_bits = 8,
  1006. .cache_type = REGCACHE_RBTREE,
  1007. .volatile_reg = sc16is7xx_regmap_volatile,
  1008. .precious_reg = sc16is7xx_regmap_precious,
  1009. };
  1010. static int sc16is7xx_i2c_probe(struct i2c_client *i2c,
  1011. const struct i2c_device_id *id)
  1012. {
  1013. struct sc16is7xx_devtype *devtype;
  1014. unsigned long flags = 0;
  1015. struct regmap *regmap;
  1016. if (i2c->dev.of_node) {
  1017. const struct of_device_id *of_id =
  1018. of_match_device(sc16is7xx_dt_ids, &i2c->dev);
  1019. devtype = (struct sc16is7xx_devtype *)of_id->data;
  1020. } else {
  1021. devtype = (struct sc16is7xx_devtype *)id->driver_data;
  1022. flags = IRQF_TRIGGER_FALLING;
  1023. }
  1024. regcfg.max_register = (0xf << SC16IS7XX_REG_SHIFT) |
  1025. (devtype->nr_uart - 1);
  1026. regmap = devm_regmap_init_i2c(i2c, &regcfg);
  1027. return sc16is7xx_probe(&i2c->dev, devtype, regmap, i2c->irq, flags);
  1028. }
  1029. static int sc16is7xx_i2c_remove(struct i2c_client *client)
  1030. {
  1031. return sc16is7xx_remove(&client->dev);
  1032. }
  1033. static const struct i2c_device_id sc16is7xx_i2c_id_table[] = {
  1034. { "sc16is74x", (kernel_ulong_t)&sc16is74x_devtype, },
  1035. { "sc16is750", (kernel_ulong_t)&sc16is750_devtype, },
  1036. { "sc16is752", (kernel_ulong_t)&sc16is752_devtype, },
  1037. { "sc16is760", (kernel_ulong_t)&sc16is760_devtype, },
  1038. { "sc16is762", (kernel_ulong_t)&sc16is762_devtype, },
  1039. { }
  1040. };
  1041. MODULE_DEVICE_TABLE(i2c, sc16is7xx_i2c_id_table);
  1042. static struct i2c_driver sc16is7xx_i2c_uart_driver = {
  1043. .driver = {
  1044. .name = SC16IS7XX_NAME,
  1045. .owner = THIS_MODULE,
  1046. .of_match_table = of_match_ptr(sc16is7xx_dt_ids),
  1047. },
  1048. .probe = sc16is7xx_i2c_probe,
  1049. .remove = sc16is7xx_i2c_remove,
  1050. .id_table = sc16is7xx_i2c_id_table,
  1051. };
  1052. module_i2c_driver(sc16is7xx_i2c_uart_driver);
  1053. MODULE_ALIAS("i2c:sc16is7xx");
  1054. MODULE_LICENSE("GPL");
  1055. MODULE_AUTHOR("Jon Ringle <jringle@gridpoint.com>");
  1056. MODULE_DESCRIPTION("SC16IS7XX serial driver");