i2c-omap.c 33 KB

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  1. /*
  2. * TI OMAP I2C master mode driver
  3. *
  4. * Copyright (C) 2003 MontaVista Software, Inc.
  5. * Copyright (C) 2005 Nokia Corporation
  6. * Copyright (C) 2004 - 2007 Texas Instruments.
  7. *
  8. * Originally written by MontaVista Software, Inc.
  9. * Additional contributions by:
  10. * Tony Lindgren <tony@atomide.com>
  11. * Imre Deak <imre.deak@nokia.com>
  12. * Juha Yrjölä <juha.yrjola@solidboot.com>
  13. * Syed Khasim <x0khasim@ti.com>
  14. * Nishant Menon <nm@ti.com>
  15. *
  16. * This program is free software; you can redistribute it and/or modify
  17. * it under the terms of the GNU General Public License as published by
  18. * the Free Software Foundation; either version 2 of the License, or
  19. * (at your option) any later version.
  20. *
  21. * This program is distributed in the hope that it will be useful,
  22. * but WITHOUT ANY WARRANTY; without even the implied warranty of
  23. * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  24. * GNU General Public License for more details.
  25. *
  26. * You should have received a copy of the GNU General Public License
  27. * along with this program; if not, write to the Free Software
  28. * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  29. */
  30. #include <linux/module.h>
  31. #include <linux/delay.h>
  32. #include <linux/i2c.h>
  33. #include <linux/err.h>
  34. #include <linux/interrupt.h>
  35. #include <linux/completion.h>
  36. #include <linux/platform_device.h>
  37. #include <linux/clk.h>
  38. #include <linux/io.h>
  39. #include <linux/of.h>
  40. #include <linux/of_i2c.h>
  41. #include <linux/of_device.h>
  42. #include <linux/slab.h>
  43. #include <linux/i2c-omap.h>
  44. #include <linux/pm_runtime.h>
  45. /* I2C controller revisions */
  46. #define OMAP_I2C_OMAP1_REV_2 0x20
  47. /* I2C controller revisions present on specific hardware */
  48. #define OMAP_I2C_REV_ON_2430 0x36
  49. #define OMAP_I2C_REV_ON_3430_3530 0x3C
  50. #define OMAP_I2C_REV_ON_3630_4430 0x40
  51. /* timeout waiting for the controller to respond */
  52. #define OMAP_I2C_TIMEOUT (msecs_to_jiffies(1000))
  53. /* For OMAP3 I2C_IV has changed to I2C_WE (wakeup enable) */
  54. enum {
  55. OMAP_I2C_REV_REG = 0,
  56. OMAP_I2C_IE_REG,
  57. OMAP_I2C_STAT_REG,
  58. OMAP_I2C_IV_REG,
  59. OMAP_I2C_WE_REG,
  60. OMAP_I2C_SYSS_REG,
  61. OMAP_I2C_BUF_REG,
  62. OMAP_I2C_CNT_REG,
  63. OMAP_I2C_DATA_REG,
  64. OMAP_I2C_SYSC_REG,
  65. OMAP_I2C_CON_REG,
  66. OMAP_I2C_OA_REG,
  67. OMAP_I2C_SA_REG,
  68. OMAP_I2C_PSC_REG,
  69. OMAP_I2C_SCLL_REG,
  70. OMAP_I2C_SCLH_REG,
  71. OMAP_I2C_SYSTEST_REG,
  72. OMAP_I2C_BUFSTAT_REG,
  73. /* only on OMAP4430 */
  74. OMAP_I2C_IP_V2_REVNB_LO,
  75. OMAP_I2C_IP_V2_REVNB_HI,
  76. OMAP_I2C_IP_V2_IRQSTATUS_RAW,
  77. OMAP_I2C_IP_V2_IRQENABLE_SET,
  78. OMAP_I2C_IP_V2_IRQENABLE_CLR,
  79. };
  80. /* I2C Interrupt Enable Register (OMAP_I2C_IE): */
  81. #define OMAP_I2C_IE_XDR (1 << 14) /* TX Buffer drain int enable */
  82. #define OMAP_I2C_IE_RDR (1 << 13) /* RX Buffer drain int enable */
  83. #define OMAP_I2C_IE_XRDY (1 << 4) /* TX data ready int enable */
  84. #define OMAP_I2C_IE_RRDY (1 << 3) /* RX data ready int enable */
  85. #define OMAP_I2C_IE_ARDY (1 << 2) /* Access ready int enable */
  86. #define OMAP_I2C_IE_NACK (1 << 1) /* No ack interrupt enable */
  87. #define OMAP_I2C_IE_AL (1 << 0) /* Arbitration lost int ena */
  88. /* I2C Status Register (OMAP_I2C_STAT): */
  89. #define OMAP_I2C_STAT_XDR (1 << 14) /* TX Buffer draining */
  90. #define OMAP_I2C_STAT_RDR (1 << 13) /* RX Buffer draining */
  91. #define OMAP_I2C_STAT_BB (1 << 12) /* Bus busy */
  92. #define OMAP_I2C_STAT_ROVR (1 << 11) /* Receive overrun */
  93. #define OMAP_I2C_STAT_XUDF (1 << 10) /* Transmit underflow */
  94. #define OMAP_I2C_STAT_AAS (1 << 9) /* Address as slave */
  95. #define OMAP_I2C_STAT_AD0 (1 << 8) /* Address zero */
  96. #define OMAP_I2C_STAT_XRDY (1 << 4) /* Transmit data ready */
  97. #define OMAP_I2C_STAT_RRDY (1 << 3) /* Receive data ready */
  98. #define OMAP_I2C_STAT_ARDY (1 << 2) /* Register access ready */
  99. #define OMAP_I2C_STAT_NACK (1 << 1) /* No ack interrupt enable */
  100. #define OMAP_I2C_STAT_AL (1 << 0) /* Arbitration lost int ena */
  101. /* I2C WE wakeup enable register */
  102. #define OMAP_I2C_WE_XDR_WE (1 << 14) /* TX drain wakup */
  103. #define OMAP_I2C_WE_RDR_WE (1 << 13) /* RX drain wakeup */
  104. #define OMAP_I2C_WE_AAS_WE (1 << 9) /* Address as slave wakeup*/
  105. #define OMAP_I2C_WE_BF_WE (1 << 8) /* Bus free wakeup */
  106. #define OMAP_I2C_WE_STC_WE (1 << 6) /* Start condition wakeup */
  107. #define OMAP_I2C_WE_GC_WE (1 << 5) /* General call wakeup */
  108. #define OMAP_I2C_WE_DRDY_WE (1 << 3) /* TX/RX data ready wakeup */
  109. #define OMAP_I2C_WE_ARDY_WE (1 << 2) /* Reg access ready wakeup */
  110. #define OMAP_I2C_WE_NACK_WE (1 << 1) /* No acknowledgment wakeup */
  111. #define OMAP_I2C_WE_AL_WE (1 << 0) /* Arbitration lost wakeup */
  112. #define OMAP_I2C_WE_ALL (OMAP_I2C_WE_XDR_WE | OMAP_I2C_WE_RDR_WE | \
  113. OMAP_I2C_WE_AAS_WE | OMAP_I2C_WE_BF_WE | \
  114. OMAP_I2C_WE_STC_WE | OMAP_I2C_WE_GC_WE | \
  115. OMAP_I2C_WE_DRDY_WE | OMAP_I2C_WE_ARDY_WE | \
  116. OMAP_I2C_WE_NACK_WE | OMAP_I2C_WE_AL_WE)
  117. /* I2C Buffer Configuration Register (OMAP_I2C_BUF): */
  118. #define OMAP_I2C_BUF_RDMA_EN (1 << 15) /* RX DMA channel enable */
  119. #define OMAP_I2C_BUF_RXFIF_CLR (1 << 14) /* RX FIFO Clear */
  120. #define OMAP_I2C_BUF_XDMA_EN (1 << 7) /* TX DMA channel enable */
  121. #define OMAP_I2C_BUF_TXFIF_CLR (1 << 6) /* TX FIFO Clear */
  122. /* I2C Configuration Register (OMAP_I2C_CON): */
  123. #define OMAP_I2C_CON_EN (1 << 15) /* I2C module enable */
  124. #define OMAP_I2C_CON_BE (1 << 14) /* Big endian mode */
  125. #define OMAP_I2C_CON_OPMODE_HS (1 << 12) /* High Speed support */
  126. #define OMAP_I2C_CON_STB (1 << 11) /* Start byte mode (master) */
  127. #define OMAP_I2C_CON_MST (1 << 10) /* Master/slave mode */
  128. #define OMAP_I2C_CON_TRX (1 << 9) /* TX/RX mode (master only) */
  129. #define OMAP_I2C_CON_XA (1 << 8) /* Expand address */
  130. #define OMAP_I2C_CON_RM (1 << 2) /* Repeat mode (master only) */
  131. #define OMAP_I2C_CON_STP (1 << 1) /* Stop cond (master only) */
  132. #define OMAP_I2C_CON_STT (1 << 0) /* Start condition (master) */
  133. /* I2C SCL time value when Master */
  134. #define OMAP_I2C_SCLL_HSSCLL 8
  135. #define OMAP_I2C_SCLH_HSSCLH 8
  136. /* I2C System Test Register (OMAP_I2C_SYSTEST): */
  137. #ifdef DEBUG
  138. #define OMAP_I2C_SYSTEST_ST_EN (1 << 15) /* System test enable */
  139. #define OMAP_I2C_SYSTEST_FREE (1 << 14) /* Free running mode */
  140. #define OMAP_I2C_SYSTEST_TMODE_MASK (3 << 12) /* Test mode select */
  141. #define OMAP_I2C_SYSTEST_TMODE_SHIFT (12) /* Test mode select */
  142. #define OMAP_I2C_SYSTEST_SCL_I (1 << 3) /* SCL line sense in */
  143. #define OMAP_I2C_SYSTEST_SCL_O (1 << 2) /* SCL line drive out */
  144. #define OMAP_I2C_SYSTEST_SDA_I (1 << 1) /* SDA line sense in */
  145. #define OMAP_I2C_SYSTEST_SDA_O (1 << 0) /* SDA line drive out */
  146. #endif
  147. /* OCP_SYSSTATUS bit definitions */
  148. #define SYSS_RESETDONE_MASK (1 << 0)
  149. /* OCP_SYSCONFIG bit definitions */
  150. #define SYSC_CLOCKACTIVITY_MASK (0x3 << 8)
  151. #define SYSC_SIDLEMODE_MASK (0x3 << 3)
  152. #define SYSC_ENAWAKEUP_MASK (1 << 2)
  153. #define SYSC_SOFTRESET_MASK (1 << 1)
  154. #define SYSC_AUTOIDLE_MASK (1 << 0)
  155. #define SYSC_IDLEMODE_SMART 0x2
  156. #define SYSC_CLOCKACTIVITY_FCLK 0x2
  157. /* Errata definitions */
  158. #define I2C_OMAP_ERRATA_I207 (1 << 0)
  159. #define I2C_OMAP_ERRATA_I462 (1 << 1)
  160. struct omap_i2c_dev {
  161. struct device *dev;
  162. void __iomem *base; /* virtual */
  163. int irq;
  164. int reg_shift; /* bit shift for I2C register addresses */
  165. struct completion cmd_complete;
  166. struct resource *ioarea;
  167. u32 latency; /* maximum mpu wkup latency */
  168. void (*set_mpu_wkup_lat)(struct device *dev,
  169. long latency);
  170. u32 speed; /* Speed of bus in kHz */
  171. u32 dtrev; /* extra revision from DT */
  172. u32 flags;
  173. u16 cmd_err;
  174. u8 *buf;
  175. u8 *regs;
  176. size_t buf_len;
  177. struct i2c_adapter adapter;
  178. u8 fifo_size; /* use as flag and value
  179. * fifo_size==0 implies no fifo
  180. * if set, should be trsh+1
  181. */
  182. u8 rev;
  183. unsigned b_hw:1; /* bad h/w fixes */
  184. u16 iestate; /* Saved interrupt register */
  185. u16 pscstate;
  186. u16 scllstate;
  187. u16 sclhstate;
  188. u16 bufstate;
  189. u16 syscstate;
  190. u16 westate;
  191. u16 errata;
  192. };
  193. static const u8 reg_map_ip_v1[] = {
  194. [OMAP_I2C_REV_REG] = 0x00,
  195. [OMAP_I2C_IE_REG] = 0x01,
  196. [OMAP_I2C_STAT_REG] = 0x02,
  197. [OMAP_I2C_IV_REG] = 0x03,
  198. [OMAP_I2C_WE_REG] = 0x03,
  199. [OMAP_I2C_SYSS_REG] = 0x04,
  200. [OMAP_I2C_BUF_REG] = 0x05,
  201. [OMAP_I2C_CNT_REG] = 0x06,
  202. [OMAP_I2C_DATA_REG] = 0x07,
  203. [OMAP_I2C_SYSC_REG] = 0x08,
  204. [OMAP_I2C_CON_REG] = 0x09,
  205. [OMAP_I2C_OA_REG] = 0x0a,
  206. [OMAP_I2C_SA_REG] = 0x0b,
  207. [OMAP_I2C_PSC_REG] = 0x0c,
  208. [OMAP_I2C_SCLL_REG] = 0x0d,
  209. [OMAP_I2C_SCLH_REG] = 0x0e,
  210. [OMAP_I2C_SYSTEST_REG] = 0x0f,
  211. [OMAP_I2C_BUFSTAT_REG] = 0x10,
  212. };
  213. static const u8 reg_map_ip_v2[] = {
  214. [OMAP_I2C_REV_REG] = 0x04,
  215. [OMAP_I2C_IE_REG] = 0x2c,
  216. [OMAP_I2C_STAT_REG] = 0x28,
  217. [OMAP_I2C_IV_REG] = 0x34,
  218. [OMAP_I2C_WE_REG] = 0x34,
  219. [OMAP_I2C_SYSS_REG] = 0x90,
  220. [OMAP_I2C_BUF_REG] = 0x94,
  221. [OMAP_I2C_CNT_REG] = 0x98,
  222. [OMAP_I2C_DATA_REG] = 0x9c,
  223. [OMAP_I2C_SYSC_REG] = 0x10,
  224. [OMAP_I2C_CON_REG] = 0xa4,
  225. [OMAP_I2C_OA_REG] = 0xa8,
  226. [OMAP_I2C_SA_REG] = 0xac,
  227. [OMAP_I2C_PSC_REG] = 0xb0,
  228. [OMAP_I2C_SCLL_REG] = 0xb4,
  229. [OMAP_I2C_SCLH_REG] = 0xb8,
  230. [OMAP_I2C_SYSTEST_REG] = 0xbC,
  231. [OMAP_I2C_BUFSTAT_REG] = 0xc0,
  232. [OMAP_I2C_IP_V2_REVNB_LO] = 0x00,
  233. [OMAP_I2C_IP_V2_REVNB_HI] = 0x04,
  234. [OMAP_I2C_IP_V2_IRQSTATUS_RAW] = 0x24,
  235. [OMAP_I2C_IP_V2_IRQENABLE_SET] = 0x2c,
  236. [OMAP_I2C_IP_V2_IRQENABLE_CLR] = 0x30,
  237. };
  238. static inline void omap_i2c_write_reg(struct omap_i2c_dev *i2c_dev,
  239. int reg, u16 val)
  240. {
  241. __raw_writew(val, i2c_dev->base +
  242. (i2c_dev->regs[reg] << i2c_dev->reg_shift));
  243. }
  244. static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg)
  245. {
  246. return __raw_readw(i2c_dev->base +
  247. (i2c_dev->regs[reg] << i2c_dev->reg_shift));
  248. }
  249. static int omap_i2c_init(struct omap_i2c_dev *dev)
  250. {
  251. u16 psc = 0, scll = 0, sclh = 0, buf = 0;
  252. u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0;
  253. unsigned long fclk_rate = 12000000;
  254. unsigned long timeout;
  255. unsigned long internal_clk = 0;
  256. struct clk *fclk;
  257. if (dev->rev >= OMAP_I2C_OMAP1_REV_2) {
  258. /* Disable I2C controller before soft reset */
  259. omap_i2c_write_reg(dev, OMAP_I2C_CON_REG,
  260. omap_i2c_read_reg(dev, OMAP_I2C_CON_REG) &
  261. ~(OMAP_I2C_CON_EN));
  262. omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, SYSC_SOFTRESET_MASK);
  263. /* For some reason we need to set the EN bit before the
  264. * reset done bit gets set. */
  265. timeout = jiffies + OMAP_I2C_TIMEOUT;
  266. omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
  267. while (!(omap_i2c_read_reg(dev, OMAP_I2C_SYSS_REG) &
  268. SYSS_RESETDONE_MASK)) {
  269. if (time_after(jiffies, timeout)) {
  270. dev_warn(dev->dev, "timeout waiting "
  271. "for controller reset\n");
  272. return -ETIMEDOUT;
  273. }
  274. msleep(1);
  275. }
  276. /* SYSC register is cleared by the reset; rewrite it */
  277. if (dev->rev == OMAP_I2C_REV_ON_2430) {
  278. omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG,
  279. SYSC_AUTOIDLE_MASK);
  280. } else if (dev->rev >= OMAP_I2C_REV_ON_3430_3530) {
  281. dev->syscstate = SYSC_AUTOIDLE_MASK;
  282. dev->syscstate |= SYSC_ENAWAKEUP_MASK;
  283. dev->syscstate |= (SYSC_IDLEMODE_SMART <<
  284. __ffs(SYSC_SIDLEMODE_MASK));
  285. dev->syscstate |= (SYSC_CLOCKACTIVITY_FCLK <<
  286. __ffs(SYSC_CLOCKACTIVITY_MASK));
  287. omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG,
  288. dev->syscstate);
  289. /*
  290. * Enabling all wakup sources to stop I2C freezing on
  291. * WFI instruction.
  292. * REVISIT: Some wkup sources might not be needed.
  293. */
  294. dev->westate = OMAP_I2C_WE_ALL;
  295. omap_i2c_write_reg(dev, OMAP_I2C_WE_REG,
  296. dev->westate);
  297. }
  298. }
  299. omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
  300. if (dev->flags & OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK) {
  301. /*
  302. * The I2C functional clock is the armxor_ck, so there's
  303. * no need to get "armxor_ck" separately. Now, if OMAP2420
  304. * always returns 12MHz for the functional clock, we can
  305. * do this bit unconditionally.
  306. */
  307. fclk = clk_get(dev->dev, "fck");
  308. fclk_rate = clk_get_rate(fclk);
  309. clk_put(fclk);
  310. /* TRM for 5912 says the I2C clock must be prescaled to be
  311. * between 7 - 12 MHz. The XOR input clock is typically
  312. * 12, 13 or 19.2 MHz. So we should have code that produces:
  313. *
  314. * XOR MHz Divider Prescaler
  315. * 12 1 0
  316. * 13 2 1
  317. * 19.2 2 1
  318. */
  319. if (fclk_rate > 12000000)
  320. psc = fclk_rate / 12000000;
  321. }
  322. if (!(dev->flags & OMAP_I2C_FLAG_SIMPLE_CLOCK)) {
  323. /*
  324. * HSI2C controller internal clk rate should be 19.2 Mhz for
  325. * HS and for all modes on 2430. On 34xx we can use lower rate
  326. * to get longer filter period for better noise suppression.
  327. * The filter is iclk (fclk for HS) period.
  328. */
  329. if (dev->speed > 400 ||
  330. dev->flags & OMAP_I2C_FLAG_FORCE_19200_INT_CLK)
  331. internal_clk = 19200;
  332. else if (dev->speed > 100)
  333. internal_clk = 9600;
  334. else
  335. internal_clk = 4000;
  336. fclk = clk_get(dev->dev, "fck");
  337. fclk_rate = clk_get_rate(fclk) / 1000;
  338. clk_put(fclk);
  339. /* Compute prescaler divisor */
  340. psc = fclk_rate / internal_clk;
  341. psc = psc - 1;
  342. /* If configured for High Speed */
  343. if (dev->speed > 400) {
  344. unsigned long scl;
  345. /* For first phase of HS mode */
  346. scl = internal_clk / 400;
  347. fsscll = scl - (scl / 3) - 7;
  348. fssclh = (scl / 3) - 5;
  349. /* For second phase of HS mode */
  350. scl = fclk_rate / dev->speed;
  351. hsscll = scl - (scl / 3) - 7;
  352. hssclh = (scl / 3) - 5;
  353. } else if (dev->speed > 100) {
  354. unsigned long scl;
  355. /* Fast mode */
  356. scl = internal_clk / dev->speed;
  357. fsscll = scl - (scl / 3) - 7;
  358. fssclh = (scl / 3) - 5;
  359. } else {
  360. /* Standard mode */
  361. fsscll = internal_clk / (dev->speed * 2) - 7;
  362. fssclh = internal_clk / (dev->speed * 2) - 5;
  363. }
  364. scll = (hsscll << OMAP_I2C_SCLL_HSSCLL) | fsscll;
  365. sclh = (hssclh << OMAP_I2C_SCLH_HSSCLH) | fssclh;
  366. } else {
  367. /* Program desired operating rate */
  368. fclk_rate /= (psc + 1) * 1000;
  369. if (psc > 2)
  370. psc = 2;
  371. scll = fclk_rate / (dev->speed * 2) - 7 + psc;
  372. sclh = fclk_rate / (dev->speed * 2) - 7 + psc;
  373. }
  374. /* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
  375. omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, psc);
  376. /* SCL low and high time values */
  377. omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, scll);
  378. omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, sclh);
  379. if (dev->fifo_size) {
  380. /* Note: setup required fifo size - 1. RTRSH and XTRSH */
  381. buf = (dev->fifo_size - 1) << 8 | OMAP_I2C_BUF_RXFIF_CLR |
  382. (dev->fifo_size - 1) | OMAP_I2C_BUF_TXFIF_CLR;
  383. omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, buf);
  384. }
  385. /* Take the I2C module out of reset: */
  386. omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
  387. /* Enable interrupts */
  388. dev->iestate = (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY |
  389. OMAP_I2C_IE_ARDY | OMAP_I2C_IE_NACK |
  390. OMAP_I2C_IE_AL) | ((dev->fifo_size) ?
  391. (OMAP_I2C_IE_RDR | OMAP_I2C_IE_XDR) : 0);
  392. omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
  393. if (dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
  394. dev->pscstate = psc;
  395. dev->scllstate = scll;
  396. dev->sclhstate = sclh;
  397. dev->bufstate = buf;
  398. }
  399. return 0;
  400. }
  401. /*
  402. * Waiting on Bus Busy
  403. */
  404. static int omap_i2c_wait_for_bb(struct omap_i2c_dev *dev)
  405. {
  406. unsigned long timeout;
  407. timeout = jiffies + OMAP_I2C_TIMEOUT;
  408. while (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG) & OMAP_I2C_STAT_BB) {
  409. if (time_after(jiffies, timeout)) {
  410. dev_warn(dev->dev, "timeout waiting for bus ready\n");
  411. return -ETIMEDOUT;
  412. }
  413. msleep(1);
  414. }
  415. return 0;
  416. }
  417. /*
  418. * Low level master read/write transaction.
  419. */
  420. static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
  421. struct i2c_msg *msg, int stop)
  422. {
  423. struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
  424. unsigned long timeout;
  425. u16 w;
  426. dev_dbg(dev->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n",
  427. msg->addr, msg->len, msg->flags, stop);
  428. if (msg->len == 0)
  429. return -EINVAL;
  430. omap_i2c_write_reg(dev, OMAP_I2C_SA_REG, msg->addr);
  431. /* REVISIT: Could the STB bit of I2C_CON be used with probing? */
  432. dev->buf = msg->buf;
  433. dev->buf_len = msg->len;
  434. omap_i2c_write_reg(dev, OMAP_I2C_CNT_REG, dev->buf_len);
  435. /* Clear the FIFO Buffers */
  436. w = omap_i2c_read_reg(dev, OMAP_I2C_BUF_REG);
  437. w |= OMAP_I2C_BUF_RXFIF_CLR | OMAP_I2C_BUF_TXFIF_CLR;
  438. omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, w);
  439. INIT_COMPLETION(dev->cmd_complete);
  440. dev->cmd_err = 0;
  441. w = OMAP_I2C_CON_EN | OMAP_I2C_CON_MST | OMAP_I2C_CON_STT;
  442. /* High speed configuration */
  443. if (dev->speed > 400)
  444. w |= OMAP_I2C_CON_OPMODE_HS;
  445. if (msg->flags & I2C_M_STOP)
  446. stop = 1;
  447. if (msg->flags & I2C_M_TEN)
  448. w |= OMAP_I2C_CON_XA;
  449. if (!(msg->flags & I2C_M_RD))
  450. w |= OMAP_I2C_CON_TRX;
  451. if (!dev->b_hw && stop)
  452. w |= OMAP_I2C_CON_STP;
  453. omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
  454. /*
  455. * Don't write stt and stp together on some hardware.
  456. */
  457. if (dev->b_hw && stop) {
  458. unsigned long delay = jiffies + OMAP_I2C_TIMEOUT;
  459. u16 con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
  460. while (con & OMAP_I2C_CON_STT) {
  461. con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
  462. /* Let the user know if i2c is in a bad state */
  463. if (time_after(jiffies, delay)) {
  464. dev_err(dev->dev, "controller timed out "
  465. "waiting for start condition to finish\n");
  466. return -ETIMEDOUT;
  467. }
  468. cpu_relax();
  469. }
  470. w |= OMAP_I2C_CON_STP;
  471. w &= ~OMAP_I2C_CON_STT;
  472. omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
  473. }
  474. /*
  475. * REVISIT: We should abort the transfer on signals, but the bus goes
  476. * into arbitration and we're currently unable to recover from it.
  477. */
  478. timeout = wait_for_completion_timeout(&dev->cmd_complete,
  479. OMAP_I2C_TIMEOUT);
  480. dev->buf_len = 0;
  481. if (timeout == 0) {
  482. dev_err(dev->dev, "controller timed out\n");
  483. omap_i2c_init(dev);
  484. return -ETIMEDOUT;
  485. }
  486. if (likely(!dev->cmd_err))
  487. return 0;
  488. /* We have an error */
  489. if (dev->cmd_err & (OMAP_I2C_STAT_AL | OMAP_I2C_STAT_ROVR |
  490. OMAP_I2C_STAT_XUDF)) {
  491. omap_i2c_init(dev);
  492. return -EIO;
  493. }
  494. if (dev->cmd_err & OMAP_I2C_STAT_NACK) {
  495. if (msg->flags & I2C_M_IGNORE_NAK)
  496. return 0;
  497. if (stop) {
  498. w = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
  499. w |= OMAP_I2C_CON_STP;
  500. omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
  501. }
  502. return -EREMOTEIO;
  503. }
  504. return -EIO;
  505. }
  506. /*
  507. * Prepare controller for a transaction and call omap_i2c_xfer_msg
  508. * to do the work during IRQ processing.
  509. */
  510. static int
  511. omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
  512. {
  513. struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
  514. int i;
  515. int r;
  516. r = pm_runtime_get_sync(dev->dev);
  517. if (IS_ERR_VALUE(r))
  518. return r;
  519. r = omap_i2c_wait_for_bb(dev);
  520. if (r < 0)
  521. goto out;
  522. if (dev->set_mpu_wkup_lat != NULL)
  523. dev->set_mpu_wkup_lat(dev->dev, dev->latency);
  524. for (i = 0; i < num; i++) {
  525. r = omap_i2c_xfer_msg(adap, &msgs[i], (i == (num - 1)));
  526. if (r != 0)
  527. break;
  528. }
  529. if (dev->set_mpu_wkup_lat != NULL)
  530. dev->set_mpu_wkup_lat(dev->dev, -1);
  531. if (r == 0)
  532. r = num;
  533. omap_i2c_wait_for_bb(dev);
  534. out:
  535. pm_runtime_put(dev->dev);
  536. return r;
  537. }
  538. static u32
  539. omap_i2c_func(struct i2c_adapter *adap)
  540. {
  541. return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK) |
  542. I2C_FUNC_PROTOCOL_MANGLING;
  543. }
  544. static inline void
  545. omap_i2c_complete_cmd(struct omap_i2c_dev *dev, u16 err)
  546. {
  547. dev->cmd_err |= err;
  548. complete(&dev->cmd_complete);
  549. }
  550. static inline void
  551. omap_i2c_ack_stat(struct omap_i2c_dev *dev, u16 stat)
  552. {
  553. omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat);
  554. }
  555. static inline void i2c_omap_errata_i207(struct omap_i2c_dev *dev, u16 stat)
  556. {
  557. /*
  558. * I2C Errata(Errata Nos. OMAP2: 1.67, OMAP3: 1.8)
  559. * Not applicable for OMAP4.
  560. * Under certain rare conditions, RDR could be set again
  561. * when the bus is busy, then ignore the interrupt and
  562. * clear the interrupt.
  563. */
  564. if (stat & OMAP_I2C_STAT_RDR) {
  565. /* Step 1: If RDR is set, clear it */
  566. omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
  567. /* Step 2: */
  568. if (!(omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG)
  569. & OMAP_I2C_STAT_BB)) {
  570. /* Step 3: */
  571. if (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG)
  572. & OMAP_I2C_STAT_RDR) {
  573. omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
  574. dev_dbg(dev->dev, "RDR when bus is busy.\n");
  575. }
  576. }
  577. }
  578. }
  579. /* rev1 devices are apparently only on some 15xx */
  580. #ifdef CONFIG_ARCH_OMAP15XX
  581. static irqreturn_t
  582. omap_i2c_omap1_isr(int this_irq, void *dev_id)
  583. {
  584. struct omap_i2c_dev *dev = dev_id;
  585. u16 iv, w;
  586. if (pm_runtime_suspended(dev->dev))
  587. return IRQ_NONE;
  588. iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG);
  589. switch (iv) {
  590. case 0x00: /* None */
  591. break;
  592. case 0x01: /* Arbitration lost */
  593. dev_err(dev->dev, "Arbitration lost\n");
  594. omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_AL);
  595. break;
  596. case 0x02: /* No acknowledgement */
  597. omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_NACK);
  598. omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_STP);
  599. break;
  600. case 0x03: /* Register access ready */
  601. omap_i2c_complete_cmd(dev, 0);
  602. break;
  603. case 0x04: /* Receive data ready */
  604. if (dev->buf_len) {
  605. w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
  606. *dev->buf++ = w;
  607. dev->buf_len--;
  608. if (dev->buf_len) {
  609. *dev->buf++ = w >> 8;
  610. dev->buf_len--;
  611. }
  612. } else
  613. dev_err(dev->dev, "RRDY IRQ while no data requested\n");
  614. break;
  615. case 0x05: /* Transmit data ready */
  616. if (dev->buf_len) {
  617. w = *dev->buf++;
  618. dev->buf_len--;
  619. if (dev->buf_len) {
  620. w |= *dev->buf++ << 8;
  621. dev->buf_len--;
  622. }
  623. omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
  624. } else
  625. dev_err(dev->dev, "XRDY IRQ while no data to send\n");
  626. break;
  627. default:
  628. return IRQ_NONE;
  629. }
  630. return IRQ_HANDLED;
  631. }
  632. #else
  633. #define omap_i2c_omap1_isr NULL
  634. #endif
  635. /*
  636. * OMAP3430 Errata i462: When an XRDY/XDR is hit, wait for XUDF before writing
  637. * data to DATA_REG. Otherwise some data bytes can be lost while transferring
  638. * them from the memory to the I2C interface.
  639. */
  640. static int errata_omap3_i462(struct omap_i2c_dev *dev, u16 *stat, int *err)
  641. {
  642. unsigned long timeout = 10000;
  643. while (--timeout && !(*stat & OMAP_I2C_STAT_XUDF)) {
  644. if (*stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) {
  645. omap_i2c_ack_stat(dev, *stat & (OMAP_I2C_STAT_XRDY |
  646. OMAP_I2C_STAT_XDR));
  647. return -ETIMEDOUT;
  648. }
  649. cpu_relax();
  650. *stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
  651. }
  652. if (!timeout) {
  653. dev_err(dev->dev, "timeout waiting on XUDF bit\n");
  654. return 0;
  655. }
  656. *err |= OMAP_I2C_STAT_XUDF;
  657. return 0;
  658. }
  659. static irqreturn_t
  660. omap_i2c_isr(int this_irq, void *dev_id)
  661. {
  662. struct omap_i2c_dev *dev = dev_id;
  663. u16 bits;
  664. u16 stat, w;
  665. int err, count = 0;
  666. if (pm_runtime_suspended(dev->dev))
  667. return IRQ_NONE;
  668. bits = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
  669. while ((stat = (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG))) & bits) {
  670. dev_dbg(dev->dev, "IRQ (ISR = 0x%04x)\n", stat);
  671. if (count++ == 100) {
  672. dev_warn(dev->dev, "Too much work in one IRQ\n");
  673. break;
  674. }
  675. err = 0;
  676. complete:
  677. /*
  678. * Ack the stat in one go, but [R/X]DR and [R/X]RDY should be
  679. * acked after the data operation is complete.
  680. * Ref: TRM SWPU114Q Figure 18-31
  681. */
  682. omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat &
  683. ~(OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR |
  684. OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR));
  685. if (stat & OMAP_I2C_STAT_NACK)
  686. err |= OMAP_I2C_STAT_NACK;
  687. if (stat & OMAP_I2C_STAT_AL) {
  688. dev_err(dev->dev, "Arbitration lost\n");
  689. err |= OMAP_I2C_STAT_AL;
  690. }
  691. /*
  692. * ProDB0017052: Clear ARDY bit twice
  693. */
  694. if (stat & (OMAP_I2C_STAT_ARDY | OMAP_I2C_STAT_NACK |
  695. OMAP_I2C_STAT_AL)) {
  696. omap_i2c_ack_stat(dev, stat &
  697. (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR |
  698. OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR |
  699. OMAP_I2C_STAT_ARDY));
  700. omap_i2c_complete_cmd(dev, err);
  701. return IRQ_HANDLED;
  702. }
  703. if (stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR)) {
  704. u8 num_bytes = 1;
  705. if (dev->errata & I2C_OMAP_ERRATA_I207)
  706. i2c_omap_errata_i207(dev, stat);
  707. if (dev->fifo_size) {
  708. if (stat & OMAP_I2C_STAT_RRDY)
  709. num_bytes = dev->fifo_size;
  710. else /* read RXSTAT on RDR interrupt */
  711. num_bytes = (omap_i2c_read_reg(dev,
  712. OMAP_I2C_BUFSTAT_REG)
  713. >> 8) & 0x3F;
  714. }
  715. while (num_bytes) {
  716. num_bytes--;
  717. w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
  718. if (dev->buf_len) {
  719. *dev->buf++ = w;
  720. dev->buf_len--;
  721. /*
  722. * Data reg in 2430, omap3 and
  723. * omap4 is 8 bit wide
  724. */
  725. if (dev->flags &
  726. OMAP_I2C_FLAG_16BIT_DATA_REG) {
  727. if (dev->buf_len) {
  728. *dev->buf++ = w >> 8;
  729. dev->buf_len--;
  730. }
  731. }
  732. } else {
  733. if (stat & OMAP_I2C_STAT_RRDY)
  734. dev_err(dev->dev,
  735. "RRDY IRQ while no data"
  736. " requested\n");
  737. if (stat & OMAP_I2C_STAT_RDR)
  738. dev_err(dev->dev,
  739. "RDR IRQ while no data"
  740. " requested\n");
  741. break;
  742. }
  743. }
  744. omap_i2c_ack_stat(dev,
  745. stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR));
  746. continue;
  747. }
  748. if (stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR)) {
  749. u8 num_bytes = 1;
  750. if (dev->fifo_size) {
  751. if (stat & OMAP_I2C_STAT_XRDY)
  752. num_bytes = dev->fifo_size;
  753. else /* read TXSTAT on XDR interrupt */
  754. num_bytes = omap_i2c_read_reg(dev,
  755. OMAP_I2C_BUFSTAT_REG)
  756. & 0x3F;
  757. }
  758. while (num_bytes) {
  759. num_bytes--;
  760. w = 0;
  761. if (dev->buf_len) {
  762. w = *dev->buf++;
  763. dev->buf_len--;
  764. /*
  765. * Data reg in 2430, omap3 and
  766. * omap4 is 8 bit wide
  767. */
  768. if (dev->flags &
  769. OMAP_I2C_FLAG_16BIT_DATA_REG) {
  770. if (dev->buf_len) {
  771. w |= *dev->buf++ << 8;
  772. dev->buf_len--;
  773. }
  774. }
  775. } else {
  776. if (stat & OMAP_I2C_STAT_XRDY)
  777. dev_err(dev->dev,
  778. "XRDY IRQ while no "
  779. "data to send\n");
  780. if (stat & OMAP_I2C_STAT_XDR)
  781. dev_err(dev->dev,
  782. "XDR IRQ while no "
  783. "data to send\n");
  784. break;
  785. }
  786. if ((dev->errata & I2C_OMAP_ERRATA_I462) &&
  787. errata_omap3_i462(dev, &stat, &err))
  788. goto complete;
  789. omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
  790. }
  791. omap_i2c_ack_stat(dev,
  792. stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR));
  793. continue;
  794. }
  795. if (stat & OMAP_I2C_STAT_ROVR) {
  796. dev_err(dev->dev, "Receive overrun\n");
  797. dev->cmd_err |= OMAP_I2C_STAT_ROVR;
  798. }
  799. if (stat & OMAP_I2C_STAT_XUDF) {
  800. dev_err(dev->dev, "Transmit underflow\n");
  801. dev->cmd_err |= OMAP_I2C_STAT_XUDF;
  802. }
  803. }
  804. return count ? IRQ_HANDLED : IRQ_NONE;
  805. }
  806. static const struct i2c_algorithm omap_i2c_algo = {
  807. .master_xfer = omap_i2c_xfer,
  808. .functionality = omap_i2c_func,
  809. };
  810. #ifdef CONFIG_OF
  811. static struct omap_i2c_bus_platform_data omap3_pdata = {
  812. .rev = OMAP_I2C_IP_VERSION_1,
  813. .flags = OMAP_I2C_FLAG_APPLY_ERRATA_I207 |
  814. OMAP_I2C_FLAG_RESET_REGS_POSTIDLE |
  815. OMAP_I2C_FLAG_BUS_SHIFT_2,
  816. };
  817. static struct omap_i2c_bus_platform_data omap4_pdata = {
  818. .rev = OMAP_I2C_IP_VERSION_2,
  819. };
  820. static const struct of_device_id omap_i2c_of_match[] = {
  821. {
  822. .compatible = "ti,omap4-i2c",
  823. .data = &omap4_pdata,
  824. },
  825. {
  826. .compatible = "ti,omap3-i2c",
  827. .data = &omap3_pdata,
  828. },
  829. { },
  830. };
  831. MODULE_DEVICE_TABLE(of, omap_i2c_of_match);
  832. #endif
  833. static int __devinit
  834. omap_i2c_probe(struct platform_device *pdev)
  835. {
  836. struct omap_i2c_dev *dev;
  837. struct i2c_adapter *adap;
  838. struct resource *mem, *irq, *ioarea;
  839. struct omap_i2c_bus_platform_data *pdata = pdev->dev.platform_data;
  840. struct device_node *node = pdev->dev.of_node;
  841. const struct of_device_id *match;
  842. irq_handler_t isr;
  843. int r;
  844. /* NOTE: driver uses the static register mapping */
  845. mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  846. if (!mem) {
  847. dev_err(&pdev->dev, "no mem resource?\n");
  848. return -ENODEV;
  849. }
  850. irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
  851. if (!irq) {
  852. dev_err(&pdev->dev, "no irq resource?\n");
  853. return -ENODEV;
  854. }
  855. ioarea = request_mem_region(mem->start, resource_size(mem),
  856. pdev->name);
  857. if (!ioarea) {
  858. dev_err(&pdev->dev, "I2C region already claimed\n");
  859. return -EBUSY;
  860. }
  861. dev = kzalloc(sizeof(struct omap_i2c_dev), GFP_KERNEL);
  862. if (!dev) {
  863. r = -ENOMEM;
  864. goto err_release_region;
  865. }
  866. match = of_match_device(of_match_ptr(omap_i2c_of_match), &pdev->dev);
  867. if (match) {
  868. u32 freq = 100000; /* default to 100000 Hz */
  869. pdata = match->data;
  870. dev->dtrev = pdata->rev;
  871. dev->flags = pdata->flags;
  872. of_property_read_u32(node, "clock-frequency", &freq);
  873. /* convert DT freq value in Hz into kHz for speed */
  874. dev->speed = freq / 1000;
  875. } else if (pdata != NULL) {
  876. dev->speed = pdata->clkrate;
  877. dev->flags = pdata->flags;
  878. dev->set_mpu_wkup_lat = pdata->set_mpu_wkup_lat;
  879. dev->dtrev = pdata->rev;
  880. }
  881. dev->dev = &pdev->dev;
  882. dev->irq = irq->start;
  883. dev->base = ioremap(mem->start, resource_size(mem));
  884. if (!dev->base) {
  885. r = -ENOMEM;
  886. goto err_free_mem;
  887. }
  888. platform_set_drvdata(pdev, dev);
  889. init_completion(&dev->cmd_complete);
  890. dev->reg_shift = (dev->flags >> OMAP_I2C_FLAG_BUS_SHIFT__SHIFT) & 3;
  891. if (dev->dtrev == OMAP_I2C_IP_VERSION_2)
  892. dev->regs = (u8 *)reg_map_ip_v2;
  893. else
  894. dev->regs = (u8 *)reg_map_ip_v1;
  895. pm_runtime_enable(dev->dev);
  896. r = pm_runtime_get_sync(dev->dev);
  897. if (IS_ERR_VALUE(r))
  898. goto err_free_mem;
  899. dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff;
  900. dev->errata = 0;
  901. if (dev->flags & OMAP_I2C_FLAG_APPLY_ERRATA_I207)
  902. dev->errata |= I2C_OMAP_ERRATA_I207;
  903. if (dev->rev <= OMAP_I2C_REV_ON_3430_3530)
  904. dev->errata |= I2C_OMAP_ERRATA_I462;
  905. if (!(dev->flags & OMAP_I2C_FLAG_NO_FIFO)) {
  906. u16 s;
  907. /* Set up the fifo size - Get total size */
  908. s = (omap_i2c_read_reg(dev, OMAP_I2C_BUFSTAT_REG) >> 14) & 0x3;
  909. dev->fifo_size = 0x8 << s;
  910. /*
  911. * Set up notification threshold as half the total available
  912. * size. This is to ensure that we can handle the status on int
  913. * call back latencies.
  914. */
  915. dev->fifo_size = (dev->fifo_size / 2);
  916. if (dev->rev >= OMAP_I2C_REV_ON_3630_4430)
  917. dev->b_hw = 0; /* Disable hardware fixes */
  918. else
  919. dev->b_hw = 1; /* Enable hardware fixes */
  920. /* calculate wakeup latency constraint for MPU */
  921. if (dev->set_mpu_wkup_lat != NULL)
  922. dev->latency = (1000000 * dev->fifo_size) /
  923. (1000 * dev->speed / 8);
  924. }
  925. /* reset ASAP, clearing any IRQs */
  926. omap_i2c_init(dev);
  927. isr = (dev->rev < OMAP_I2C_OMAP1_REV_2) ? omap_i2c_omap1_isr :
  928. omap_i2c_isr;
  929. r = request_irq(dev->irq, isr, IRQF_NO_SUSPEND, pdev->name, dev);
  930. if (r) {
  931. dev_err(dev->dev, "failure requesting irq %i\n", dev->irq);
  932. goto err_unuse_clocks;
  933. }
  934. dev_info(dev->dev, "bus %d rev%d.%d.%d at %d kHz\n", pdev->id,
  935. dev->dtrev, dev->rev >> 4, dev->rev & 0xf, dev->speed);
  936. adap = &dev->adapter;
  937. i2c_set_adapdata(adap, dev);
  938. adap->owner = THIS_MODULE;
  939. adap->class = I2C_CLASS_HWMON;
  940. strlcpy(adap->name, "OMAP I2C adapter", sizeof(adap->name));
  941. adap->algo = &omap_i2c_algo;
  942. adap->dev.parent = &pdev->dev;
  943. adap->dev.of_node = pdev->dev.of_node;
  944. /* i2c device drivers may be active on return from add_adapter() */
  945. adap->nr = pdev->id;
  946. r = i2c_add_numbered_adapter(adap);
  947. if (r) {
  948. dev_err(dev->dev, "failure adding adapter\n");
  949. goto err_free_irq;
  950. }
  951. of_i2c_register_devices(adap);
  952. pm_runtime_put(dev->dev);
  953. return 0;
  954. err_free_irq:
  955. free_irq(dev->irq, dev);
  956. err_unuse_clocks:
  957. omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
  958. pm_runtime_put(dev->dev);
  959. iounmap(dev->base);
  960. pm_runtime_disable(&pdev->dev);
  961. err_free_mem:
  962. platform_set_drvdata(pdev, NULL);
  963. kfree(dev);
  964. err_release_region:
  965. release_mem_region(mem->start, resource_size(mem));
  966. return r;
  967. }
  968. static int __devexit omap_i2c_remove(struct platform_device *pdev)
  969. {
  970. struct omap_i2c_dev *dev = platform_get_drvdata(pdev);
  971. struct resource *mem;
  972. int ret;
  973. platform_set_drvdata(pdev, NULL);
  974. free_irq(dev->irq, dev);
  975. i2c_del_adapter(&dev->adapter);
  976. ret = pm_runtime_get_sync(&pdev->dev);
  977. if (IS_ERR_VALUE(ret))
  978. return ret;
  979. omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
  980. pm_runtime_put(&pdev->dev);
  981. pm_runtime_disable(&pdev->dev);
  982. iounmap(dev->base);
  983. kfree(dev);
  984. mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  985. release_mem_region(mem->start, resource_size(mem));
  986. return 0;
  987. }
  988. #ifdef CONFIG_PM
  989. #ifdef CONFIG_PM_RUNTIME
  990. static int omap_i2c_runtime_suspend(struct device *dev)
  991. {
  992. struct platform_device *pdev = to_platform_device(dev);
  993. struct omap_i2c_dev *_dev = platform_get_drvdata(pdev);
  994. u16 iv;
  995. _dev->iestate = omap_i2c_read_reg(_dev, OMAP_I2C_IE_REG);
  996. omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, 0);
  997. if (_dev->rev < OMAP_I2C_OMAP1_REV_2) {
  998. iv = omap_i2c_read_reg(_dev, OMAP_I2C_IV_REG); /* Read clears */
  999. } else {
  1000. omap_i2c_write_reg(_dev, OMAP_I2C_STAT_REG, _dev->iestate);
  1001. /* Flush posted write */
  1002. omap_i2c_read_reg(_dev, OMAP_I2C_STAT_REG);
  1003. }
  1004. return 0;
  1005. }
  1006. static int omap_i2c_runtime_resume(struct device *dev)
  1007. {
  1008. struct platform_device *pdev = to_platform_device(dev);
  1009. struct omap_i2c_dev *_dev = platform_get_drvdata(pdev);
  1010. if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
  1011. omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, 0);
  1012. omap_i2c_write_reg(_dev, OMAP_I2C_PSC_REG, _dev->pscstate);
  1013. omap_i2c_write_reg(_dev, OMAP_I2C_SCLL_REG, _dev->scllstate);
  1014. omap_i2c_write_reg(_dev, OMAP_I2C_SCLH_REG, _dev->sclhstate);
  1015. omap_i2c_write_reg(_dev, OMAP_I2C_BUF_REG, _dev->bufstate);
  1016. omap_i2c_write_reg(_dev, OMAP_I2C_SYSC_REG, _dev->syscstate);
  1017. omap_i2c_write_reg(_dev, OMAP_I2C_WE_REG, _dev->westate);
  1018. omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
  1019. }
  1020. /*
  1021. * Don't write to this register if the IE state is 0 as it can
  1022. * cause deadlock.
  1023. */
  1024. if (_dev->iestate)
  1025. omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, _dev->iestate);
  1026. return 0;
  1027. }
  1028. #endif /* CONFIG_PM_RUNTIME */
  1029. static struct dev_pm_ops omap_i2c_pm_ops = {
  1030. SET_RUNTIME_PM_OPS(omap_i2c_runtime_suspend,
  1031. omap_i2c_runtime_resume, NULL)
  1032. };
  1033. #define OMAP_I2C_PM_OPS (&omap_i2c_pm_ops)
  1034. #else
  1035. #define OMAP_I2C_PM_OPS NULL
  1036. #endif /* CONFIG_PM */
  1037. static struct platform_driver omap_i2c_driver = {
  1038. .probe = omap_i2c_probe,
  1039. .remove = __devexit_p(omap_i2c_remove),
  1040. .driver = {
  1041. .name = "omap_i2c",
  1042. .owner = THIS_MODULE,
  1043. .pm = OMAP_I2C_PM_OPS,
  1044. .of_match_table = of_match_ptr(omap_i2c_of_match),
  1045. },
  1046. };
  1047. /* I2C may be needed to bring up other drivers */
  1048. static int __init
  1049. omap_i2c_init_driver(void)
  1050. {
  1051. return platform_driver_register(&omap_i2c_driver);
  1052. }
  1053. subsys_initcall(omap_i2c_init_driver);
  1054. static void __exit omap_i2c_exit_driver(void)
  1055. {
  1056. platform_driver_unregister(&omap_i2c_driver);
  1057. }
  1058. module_exit(omap_i2c_exit_driver);
  1059. MODULE_AUTHOR("MontaVista Software, Inc. (and others)");
  1060. MODULE_DESCRIPTION("TI OMAP I2C bus adapter");
  1061. MODULE_LICENSE("GPL");
  1062. MODULE_ALIAS("platform:omap_i2c");