i2c-cpm.c 17 KB

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  1. /*
  2. * Freescale CPM1/CPM2 I2C interface.
  3. * Copyright (c) 1999 Dan Malek (dmalek@jlc.net).
  4. *
  5. * moved into proper i2c interface;
  6. * Brad Parker (brad@heeltoe.com)
  7. *
  8. * Parts from dbox2_i2c.c (cvs.tuxbox.org)
  9. * (C) 2000-2001 Felix Domke (tmbinc@gmx.net), Gillem (htoa@gmx.net)
  10. *
  11. * (C) 2007 Montavista Software, Inc.
  12. * Vitaly Bordug <vitb@kernel.crashing.org>
  13. *
  14. * Converted to of_platform_device. Renamed to i2c-cpm.c.
  15. * (C) 2007,2008 Jochen Friedrich <jochen@scram.de>
  16. *
  17. * This program is free software; you can redistribute it and/or modify
  18. * it under the terms of the GNU General Public License as published by
  19. * the Free Software Foundation; either version 2 of the License, or
  20. * (at your option) any later version.
  21. *
  22. * This program is distributed in the hope that it will be useful,
  23. * but WITHOUT ANY WARRANTY; without even the implied warranty of
  24. * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  25. * GNU General Public License for more details.
  26. */
  27. #include <linux/kernel.h>
  28. #include <linux/module.h>
  29. #include <linux/delay.h>
  30. #include <linux/slab.h>
  31. #include <linux/interrupt.h>
  32. #include <linux/errno.h>
  33. #include <linux/stddef.h>
  34. #include <linux/i2c.h>
  35. #include <linux/io.h>
  36. #include <linux/dma-mapping.h>
  37. #include <linux/of_address.h>
  38. #include <linux/of_device.h>
  39. #include <linux/of_irq.h>
  40. #include <linux/of_platform.h>
  41. #include <sysdev/fsl_soc.h>
  42. #include <asm/cpm.h>
  43. /* Try to define this if you have an older CPU (earlier than rev D4) */
  44. /* However, better use a GPIO based bitbang driver in this case :/ */
  45. #undef I2C_CHIP_ERRATA
  46. #define CPM_MAX_READ 513
  47. #define CPM_MAXBD 4
  48. #define I2C_EB (0x10) /* Big endian mode */
  49. #define I2C_EB_CPM2 (0x30) /* Big endian mode, memory snoop */
  50. #define DPRAM_BASE ((u8 __iomem __force *)cpm_muram_addr(0))
  51. /* I2C parameter RAM. */
  52. struct i2c_ram {
  53. ushort rbase; /* Rx Buffer descriptor base address */
  54. ushort tbase; /* Tx Buffer descriptor base address */
  55. u_char rfcr; /* Rx function code */
  56. u_char tfcr; /* Tx function code */
  57. ushort mrblr; /* Max receive buffer length */
  58. uint rstate; /* Internal */
  59. uint rdp; /* Internal */
  60. ushort rbptr; /* Rx Buffer descriptor pointer */
  61. ushort rbc; /* Internal */
  62. uint rxtmp; /* Internal */
  63. uint tstate; /* Internal */
  64. uint tdp; /* Internal */
  65. ushort tbptr; /* Tx Buffer descriptor pointer */
  66. ushort tbc; /* Internal */
  67. uint txtmp; /* Internal */
  68. char res1[4]; /* Reserved */
  69. ushort rpbase; /* Relocation pointer */
  70. char res2[2]; /* Reserved */
  71. };
  72. #define I2COM_START 0x80
  73. #define I2COM_MASTER 0x01
  74. #define I2CER_TXE 0x10
  75. #define I2CER_BUSY 0x04
  76. #define I2CER_TXB 0x02
  77. #define I2CER_RXB 0x01
  78. #define I2MOD_EN 0x01
  79. /* I2C Registers */
  80. struct i2c_reg {
  81. u8 i2mod;
  82. u8 res1[3];
  83. u8 i2add;
  84. u8 res2[3];
  85. u8 i2brg;
  86. u8 res3[3];
  87. u8 i2com;
  88. u8 res4[3];
  89. u8 i2cer;
  90. u8 res5[3];
  91. u8 i2cmr;
  92. };
  93. struct cpm_i2c {
  94. char *base;
  95. struct platform_device *ofdev;
  96. struct i2c_adapter adap;
  97. uint dp_addr;
  98. int version; /* CPM1=1, CPM2=2 */
  99. int irq;
  100. int cp_command;
  101. int freq;
  102. struct i2c_reg __iomem *i2c_reg;
  103. struct i2c_ram __iomem *i2c_ram;
  104. u16 i2c_addr;
  105. wait_queue_head_t i2c_wait;
  106. cbd_t __iomem *tbase;
  107. cbd_t __iomem *rbase;
  108. u_char *txbuf[CPM_MAXBD];
  109. u_char *rxbuf[CPM_MAXBD];
  110. dma_addr_t txdma[CPM_MAXBD];
  111. dma_addr_t rxdma[CPM_MAXBD];
  112. };
  113. static irqreturn_t cpm_i2c_interrupt(int irq, void *dev_id)
  114. {
  115. struct cpm_i2c *cpm;
  116. struct i2c_reg __iomem *i2c_reg;
  117. struct i2c_adapter *adap = dev_id;
  118. int i;
  119. cpm = i2c_get_adapdata(dev_id);
  120. i2c_reg = cpm->i2c_reg;
  121. /* Clear interrupt. */
  122. i = in_8(&i2c_reg->i2cer);
  123. out_8(&i2c_reg->i2cer, i);
  124. dev_dbg(&adap->dev, "Interrupt: %x\n", i);
  125. wake_up(&cpm->i2c_wait);
  126. return i ? IRQ_HANDLED : IRQ_NONE;
  127. }
  128. static void cpm_reset_i2c_params(struct cpm_i2c *cpm)
  129. {
  130. struct i2c_ram __iomem *i2c_ram = cpm->i2c_ram;
  131. /* Set up the I2C parameters in the parameter ram. */
  132. out_be16(&i2c_ram->tbase, (u8 __iomem *)cpm->tbase - DPRAM_BASE);
  133. out_be16(&i2c_ram->rbase, (u8 __iomem *)cpm->rbase - DPRAM_BASE);
  134. if (cpm->version == 1) {
  135. out_8(&i2c_ram->tfcr, I2C_EB);
  136. out_8(&i2c_ram->rfcr, I2C_EB);
  137. } else {
  138. out_8(&i2c_ram->tfcr, I2C_EB_CPM2);
  139. out_8(&i2c_ram->rfcr, I2C_EB_CPM2);
  140. }
  141. out_be16(&i2c_ram->mrblr, CPM_MAX_READ);
  142. out_be32(&i2c_ram->rstate, 0);
  143. out_be32(&i2c_ram->rdp, 0);
  144. out_be16(&i2c_ram->rbptr, 0);
  145. out_be16(&i2c_ram->rbc, 0);
  146. out_be32(&i2c_ram->rxtmp, 0);
  147. out_be32(&i2c_ram->tstate, 0);
  148. out_be32(&i2c_ram->tdp, 0);
  149. out_be16(&i2c_ram->tbptr, 0);
  150. out_be16(&i2c_ram->tbc, 0);
  151. out_be32(&i2c_ram->txtmp, 0);
  152. }
  153. static void cpm_i2c_force_close(struct i2c_adapter *adap)
  154. {
  155. struct cpm_i2c *cpm = i2c_get_adapdata(adap);
  156. struct i2c_reg __iomem *i2c_reg = cpm->i2c_reg;
  157. dev_dbg(&adap->dev, "cpm_i2c_force_close()\n");
  158. cpm_command(cpm->cp_command, CPM_CR_CLOSE_RX_BD);
  159. out_8(&i2c_reg->i2cmr, 0x00); /* Disable all interrupts */
  160. out_8(&i2c_reg->i2cer, 0xff);
  161. }
  162. static void cpm_i2c_parse_message(struct i2c_adapter *adap,
  163. struct i2c_msg *pmsg, int num, int tx, int rx)
  164. {
  165. cbd_t __iomem *tbdf;
  166. cbd_t __iomem *rbdf;
  167. u_char addr;
  168. u_char *tb;
  169. u_char *rb;
  170. struct cpm_i2c *cpm = i2c_get_adapdata(adap);
  171. tbdf = cpm->tbase + tx;
  172. rbdf = cpm->rbase + rx;
  173. addr = i2c_8bit_addr_from_msg(pmsg);
  174. tb = cpm->txbuf[tx];
  175. rb = cpm->rxbuf[rx];
  176. /* Align read buffer */
  177. rb = (u_char *) (((ulong) rb + 1) & ~1);
  178. tb[0] = addr; /* Device address byte w/rw flag */
  179. out_be16(&tbdf->cbd_datlen, pmsg->len + 1);
  180. out_be16(&tbdf->cbd_sc, 0);
  181. if (!(pmsg->flags & I2C_M_NOSTART))
  182. setbits16(&tbdf->cbd_sc, BD_I2C_START);
  183. if (tx + 1 == num)
  184. setbits16(&tbdf->cbd_sc, BD_SC_LAST | BD_SC_WRAP);
  185. if (pmsg->flags & I2C_M_RD) {
  186. /*
  187. * To read, we need an empty buffer of the proper length.
  188. * All that is used is the first byte for address, the remainder
  189. * is just used for timing (and doesn't really have to exist).
  190. */
  191. dev_dbg(&adap->dev, "cpm_i2c_read(abyte=0x%x)\n", addr);
  192. out_be16(&rbdf->cbd_datlen, 0);
  193. out_be16(&rbdf->cbd_sc, BD_SC_EMPTY | BD_SC_INTRPT);
  194. if (rx + 1 == CPM_MAXBD)
  195. setbits16(&rbdf->cbd_sc, BD_SC_WRAP);
  196. eieio();
  197. setbits16(&tbdf->cbd_sc, BD_SC_READY);
  198. } else {
  199. dev_dbg(&adap->dev, "cpm_i2c_write(abyte=0x%x)\n", addr);
  200. memcpy(tb+1, pmsg->buf, pmsg->len);
  201. eieio();
  202. setbits16(&tbdf->cbd_sc, BD_SC_READY | BD_SC_INTRPT);
  203. }
  204. }
  205. static int cpm_i2c_check_message(struct i2c_adapter *adap,
  206. struct i2c_msg *pmsg, int tx, int rx)
  207. {
  208. cbd_t __iomem *tbdf;
  209. cbd_t __iomem *rbdf;
  210. u_char *tb;
  211. u_char *rb;
  212. struct cpm_i2c *cpm = i2c_get_adapdata(adap);
  213. tbdf = cpm->tbase + tx;
  214. rbdf = cpm->rbase + rx;
  215. tb = cpm->txbuf[tx];
  216. rb = cpm->rxbuf[rx];
  217. /* Align read buffer */
  218. rb = (u_char *) (((uint) rb + 1) & ~1);
  219. eieio();
  220. if (pmsg->flags & I2C_M_RD) {
  221. dev_dbg(&adap->dev, "tx sc 0x%04x, rx sc 0x%04x\n",
  222. in_be16(&tbdf->cbd_sc), in_be16(&rbdf->cbd_sc));
  223. if (in_be16(&tbdf->cbd_sc) & BD_SC_NAK) {
  224. dev_dbg(&adap->dev, "I2C read; No ack\n");
  225. return -ENXIO;
  226. }
  227. if (in_be16(&rbdf->cbd_sc) & BD_SC_EMPTY) {
  228. dev_err(&adap->dev,
  229. "I2C read; complete but rbuf empty\n");
  230. return -EREMOTEIO;
  231. }
  232. if (in_be16(&rbdf->cbd_sc) & BD_SC_OV) {
  233. dev_err(&adap->dev, "I2C read; Overrun\n");
  234. return -EREMOTEIO;
  235. }
  236. memcpy(pmsg->buf, rb, pmsg->len);
  237. } else {
  238. dev_dbg(&adap->dev, "tx sc %d 0x%04x\n", tx,
  239. in_be16(&tbdf->cbd_sc));
  240. if (in_be16(&tbdf->cbd_sc) & BD_SC_NAK) {
  241. dev_dbg(&adap->dev, "I2C write; No ack\n");
  242. return -ENXIO;
  243. }
  244. if (in_be16(&tbdf->cbd_sc) & BD_SC_UN) {
  245. dev_err(&adap->dev, "I2C write; Underrun\n");
  246. return -EIO;
  247. }
  248. if (in_be16(&tbdf->cbd_sc) & BD_SC_CL) {
  249. dev_err(&adap->dev, "I2C write; Collision\n");
  250. return -EIO;
  251. }
  252. }
  253. return 0;
  254. }
  255. static int cpm_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
  256. {
  257. struct cpm_i2c *cpm = i2c_get_adapdata(adap);
  258. struct i2c_reg __iomem *i2c_reg = cpm->i2c_reg;
  259. struct i2c_ram __iomem *i2c_ram = cpm->i2c_ram;
  260. struct i2c_msg *pmsg;
  261. int ret;
  262. int tptr;
  263. int rptr;
  264. cbd_t __iomem *tbdf;
  265. cbd_t __iomem *rbdf;
  266. /* Reset to use first buffer */
  267. out_be16(&i2c_ram->rbptr, in_be16(&i2c_ram->rbase));
  268. out_be16(&i2c_ram->tbptr, in_be16(&i2c_ram->tbase));
  269. tbdf = cpm->tbase;
  270. rbdf = cpm->rbase;
  271. tptr = 0;
  272. rptr = 0;
  273. /*
  274. * If there was a collision in the last i2c transaction,
  275. * Set I2COM_MASTER as it was cleared during collision.
  276. */
  277. if (in_be16(&tbdf->cbd_sc) & BD_SC_CL) {
  278. out_8(&cpm->i2c_reg->i2com, I2COM_MASTER);
  279. }
  280. while (tptr < num) {
  281. pmsg = &msgs[tptr];
  282. dev_dbg(&adap->dev, "R: %d T: %d\n", rptr, tptr);
  283. cpm_i2c_parse_message(adap, pmsg, num, tptr, rptr);
  284. if (pmsg->flags & I2C_M_RD)
  285. rptr++;
  286. tptr++;
  287. }
  288. /* Start transfer now */
  289. /* Enable RX/TX/Error interupts */
  290. out_8(&i2c_reg->i2cmr, I2CER_TXE | I2CER_TXB | I2CER_RXB);
  291. out_8(&i2c_reg->i2cer, 0xff); /* Clear interrupt status */
  292. /* Chip bug, set enable here */
  293. setbits8(&i2c_reg->i2mod, I2MOD_EN); /* Enable */
  294. /* Begin transmission */
  295. setbits8(&i2c_reg->i2com, I2COM_START);
  296. tptr = 0;
  297. rptr = 0;
  298. while (tptr < num) {
  299. /* Check for outstanding messages */
  300. dev_dbg(&adap->dev, "test ready.\n");
  301. pmsg = &msgs[tptr];
  302. if (pmsg->flags & I2C_M_RD)
  303. ret = wait_event_timeout(cpm->i2c_wait,
  304. (in_be16(&tbdf[tptr].cbd_sc) & BD_SC_NAK) ||
  305. !(in_be16(&rbdf[rptr].cbd_sc) & BD_SC_EMPTY),
  306. 1 * HZ);
  307. else
  308. ret = wait_event_timeout(cpm->i2c_wait,
  309. !(in_be16(&tbdf[tptr].cbd_sc) & BD_SC_READY),
  310. 1 * HZ);
  311. if (ret == 0) {
  312. ret = -EREMOTEIO;
  313. dev_err(&adap->dev, "I2C transfer: timeout\n");
  314. goto out_err;
  315. }
  316. if (ret > 0) {
  317. dev_dbg(&adap->dev, "ready.\n");
  318. ret = cpm_i2c_check_message(adap, pmsg, tptr, rptr);
  319. tptr++;
  320. if (pmsg->flags & I2C_M_RD)
  321. rptr++;
  322. if (ret)
  323. goto out_err;
  324. }
  325. }
  326. #ifdef I2C_CHIP_ERRATA
  327. /*
  328. * Chip errata, clear enable. This is not needed on rev D4 CPUs.
  329. * Disabling I2C too early may cause too short stop condition
  330. */
  331. udelay(4);
  332. clrbits8(&i2c_reg->i2mod, I2MOD_EN);
  333. #endif
  334. return (num);
  335. out_err:
  336. cpm_i2c_force_close(adap);
  337. #ifdef I2C_CHIP_ERRATA
  338. /*
  339. * Chip errata, clear enable. This is not needed on rev D4 CPUs.
  340. */
  341. clrbits8(&i2c_reg->i2mod, I2MOD_EN);
  342. #endif
  343. return ret;
  344. }
  345. static u32 cpm_i2c_func(struct i2c_adapter *adap)
  346. {
  347. return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
  348. }
  349. /* -----exported algorithm data: ------------------------------------- */
  350. static const struct i2c_algorithm cpm_i2c_algo = {
  351. .master_xfer = cpm_i2c_xfer,
  352. .functionality = cpm_i2c_func,
  353. };
  354. /* CPM_MAX_READ is also limiting writes according to the code! */
  355. static struct i2c_adapter_quirks cpm_i2c_quirks = {
  356. .max_num_msgs = CPM_MAXBD,
  357. .max_read_len = CPM_MAX_READ,
  358. .max_write_len = CPM_MAX_READ,
  359. };
  360. static const struct i2c_adapter cpm_ops = {
  361. .owner = THIS_MODULE,
  362. .name = "i2c-cpm",
  363. .algo = &cpm_i2c_algo,
  364. .quirks = &cpm_i2c_quirks,
  365. };
  366. static int cpm_i2c_setup(struct cpm_i2c *cpm)
  367. {
  368. struct platform_device *ofdev = cpm->ofdev;
  369. const u32 *data;
  370. int len, ret, i;
  371. void __iomem *i2c_base;
  372. cbd_t __iomem *tbdf;
  373. cbd_t __iomem *rbdf;
  374. unsigned char brg;
  375. dev_dbg(&cpm->ofdev->dev, "cpm_i2c_setup()\n");
  376. init_waitqueue_head(&cpm->i2c_wait);
  377. cpm->irq = irq_of_parse_and_map(ofdev->dev.of_node, 0);
  378. if (!cpm->irq)
  379. return -EINVAL;
  380. /* Install interrupt handler. */
  381. ret = request_irq(cpm->irq, cpm_i2c_interrupt, 0, "cpm_i2c",
  382. &cpm->adap);
  383. if (ret)
  384. return ret;
  385. /* I2C parameter RAM */
  386. i2c_base = of_iomap(ofdev->dev.of_node, 1);
  387. if (i2c_base == NULL) {
  388. ret = -EINVAL;
  389. goto out_irq;
  390. }
  391. if (of_device_is_compatible(ofdev->dev.of_node, "fsl,cpm1-i2c")) {
  392. /* Check for and use a microcode relocation patch. */
  393. cpm->i2c_ram = i2c_base;
  394. cpm->i2c_addr = in_be16(&cpm->i2c_ram->rpbase);
  395. /*
  396. * Maybe should use cpm_muram_alloc instead of hardcoding
  397. * this in micropatch.c
  398. */
  399. if (cpm->i2c_addr) {
  400. cpm->i2c_ram = cpm_muram_addr(cpm->i2c_addr);
  401. iounmap(i2c_base);
  402. }
  403. cpm->version = 1;
  404. } else if (of_device_is_compatible(ofdev->dev.of_node, "fsl,cpm2-i2c")) {
  405. cpm->i2c_addr = cpm_muram_alloc(sizeof(struct i2c_ram), 64);
  406. cpm->i2c_ram = cpm_muram_addr(cpm->i2c_addr);
  407. out_be16(i2c_base, cpm->i2c_addr);
  408. iounmap(i2c_base);
  409. cpm->version = 2;
  410. } else {
  411. iounmap(i2c_base);
  412. ret = -EINVAL;
  413. goto out_irq;
  414. }
  415. /* I2C control/status registers */
  416. cpm->i2c_reg = of_iomap(ofdev->dev.of_node, 0);
  417. if (cpm->i2c_reg == NULL) {
  418. ret = -EINVAL;
  419. goto out_ram;
  420. }
  421. data = of_get_property(ofdev->dev.of_node, "fsl,cpm-command", &len);
  422. if (!data || len != 4) {
  423. ret = -EINVAL;
  424. goto out_reg;
  425. }
  426. cpm->cp_command = *data;
  427. data = of_get_property(ofdev->dev.of_node, "linux,i2c-class", &len);
  428. if (data && len == 4)
  429. cpm->adap.class = *data;
  430. data = of_get_property(ofdev->dev.of_node, "clock-frequency", &len);
  431. if (data && len == 4)
  432. cpm->freq = *data;
  433. else
  434. cpm->freq = 60000; /* use 60kHz i2c clock by default */
  435. /*
  436. * Allocate space for CPM_MAXBD transmit and receive buffer
  437. * descriptors in the DP ram.
  438. */
  439. cpm->dp_addr = cpm_muram_alloc(sizeof(cbd_t) * 2 * CPM_MAXBD, 8);
  440. if (!cpm->dp_addr) {
  441. ret = -ENOMEM;
  442. goto out_reg;
  443. }
  444. cpm->tbase = cpm_muram_addr(cpm->dp_addr);
  445. cpm->rbase = cpm_muram_addr(cpm->dp_addr + sizeof(cbd_t) * CPM_MAXBD);
  446. /* Allocate TX and RX buffers */
  447. tbdf = cpm->tbase;
  448. rbdf = cpm->rbase;
  449. for (i = 0; i < CPM_MAXBD; i++) {
  450. cpm->rxbuf[i] = dma_alloc_coherent(&cpm->ofdev->dev,
  451. CPM_MAX_READ + 1,
  452. &cpm->rxdma[i], GFP_KERNEL);
  453. if (!cpm->rxbuf[i]) {
  454. ret = -ENOMEM;
  455. goto out_muram;
  456. }
  457. out_be32(&rbdf[i].cbd_bufaddr, ((cpm->rxdma[i] + 1) & ~1));
  458. cpm->txbuf[i] = (unsigned char *)dma_alloc_coherent(&cpm->ofdev->dev, CPM_MAX_READ + 1, &cpm->txdma[i], GFP_KERNEL);
  459. if (!cpm->txbuf[i]) {
  460. ret = -ENOMEM;
  461. goto out_muram;
  462. }
  463. out_be32(&tbdf[i].cbd_bufaddr, cpm->txdma[i]);
  464. }
  465. /* Initialize Tx/Rx parameters. */
  466. cpm_reset_i2c_params(cpm);
  467. dev_dbg(&cpm->ofdev->dev, "i2c_ram 0x%p, i2c_addr 0x%04x, freq %d\n",
  468. cpm->i2c_ram, cpm->i2c_addr, cpm->freq);
  469. dev_dbg(&cpm->ofdev->dev, "tbase 0x%04x, rbase 0x%04x\n",
  470. (u8 __iomem *)cpm->tbase - DPRAM_BASE,
  471. (u8 __iomem *)cpm->rbase - DPRAM_BASE);
  472. cpm_command(cpm->cp_command, CPM_CR_INIT_TRX);
  473. /*
  474. * Select an invalid address. Just make sure we don't use loopback mode
  475. */
  476. out_8(&cpm->i2c_reg->i2add, 0x7f << 1);
  477. /*
  478. * PDIV is set to 00 in i2mod, so brgclk/32 is used as input to the
  479. * i2c baud rate generator. This is divided by 2 x (DIV + 3) to get
  480. * the actual i2c bus frequency.
  481. */
  482. brg = get_brgfreq() / (32 * 2 * cpm->freq) - 3;
  483. out_8(&cpm->i2c_reg->i2brg, brg);
  484. out_8(&cpm->i2c_reg->i2mod, 0x00);
  485. out_8(&cpm->i2c_reg->i2com, I2COM_MASTER); /* Master mode */
  486. /* Disable interrupts. */
  487. out_8(&cpm->i2c_reg->i2cmr, 0);
  488. out_8(&cpm->i2c_reg->i2cer, 0xff);
  489. return 0;
  490. out_muram:
  491. for (i = 0; i < CPM_MAXBD; i++) {
  492. if (cpm->rxbuf[i])
  493. dma_free_coherent(&cpm->ofdev->dev, CPM_MAX_READ + 1,
  494. cpm->rxbuf[i], cpm->rxdma[i]);
  495. if (cpm->txbuf[i])
  496. dma_free_coherent(&cpm->ofdev->dev, CPM_MAX_READ + 1,
  497. cpm->txbuf[i], cpm->txdma[i]);
  498. }
  499. cpm_muram_free(cpm->dp_addr);
  500. out_reg:
  501. iounmap(cpm->i2c_reg);
  502. out_ram:
  503. if ((cpm->version == 1) && (!cpm->i2c_addr))
  504. iounmap(cpm->i2c_ram);
  505. if (cpm->version == 2)
  506. cpm_muram_free(cpm->i2c_addr);
  507. out_irq:
  508. free_irq(cpm->irq, &cpm->adap);
  509. return ret;
  510. }
  511. static void cpm_i2c_shutdown(struct cpm_i2c *cpm)
  512. {
  513. int i;
  514. /* Shut down I2C. */
  515. clrbits8(&cpm->i2c_reg->i2mod, I2MOD_EN);
  516. /* Disable interrupts */
  517. out_8(&cpm->i2c_reg->i2cmr, 0);
  518. out_8(&cpm->i2c_reg->i2cer, 0xff);
  519. free_irq(cpm->irq, &cpm->adap);
  520. /* Free all memory */
  521. for (i = 0; i < CPM_MAXBD; i++) {
  522. dma_free_coherent(&cpm->ofdev->dev, CPM_MAX_READ + 1,
  523. cpm->rxbuf[i], cpm->rxdma[i]);
  524. dma_free_coherent(&cpm->ofdev->dev, CPM_MAX_READ + 1,
  525. cpm->txbuf[i], cpm->txdma[i]);
  526. }
  527. cpm_muram_free(cpm->dp_addr);
  528. iounmap(cpm->i2c_reg);
  529. if ((cpm->version == 1) && (!cpm->i2c_addr))
  530. iounmap(cpm->i2c_ram);
  531. if (cpm->version == 2)
  532. cpm_muram_free(cpm->i2c_addr);
  533. }
  534. static int cpm_i2c_probe(struct platform_device *ofdev)
  535. {
  536. int result, len;
  537. struct cpm_i2c *cpm;
  538. const u32 *data;
  539. cpm = kzalloc(sizeof(struct cpm_i2c), GFP_KERNEL);
  540. if (!cpm)
  541. return -ENOMEM;
  542. cpm->ofdev = ofdev;
  543. platform_set_drvdata(ofdev, cpm);
  544. cpm->adap = cpm_ops;
  545. i2c_set_adapdata(&cpm->adap, cpm);
  546. cpm->adap.dev.parent = &ofdev->dev;
  547. cpm->adap.dev.of_node = of_node_get(ofdev->dev.of_node);
  548. result = cpm_i2c_setup(cpm);
  549. if (result) {
  550. dev_err(&ofdev->dev, "Unable to init hardware\n");
  551. goto out_free;
  552. }
  553. /* register new adapter to i2c module... */
  554. data = of_get_property(ofdev->dev.of_node, "linux,i2c-index", &len);
  555. cpm->adap.nr = (data && len == 4) ? be32_to_cpup(data) : -1;
  556. result = i2c_add_numbered_adapter(&cpm->adap);
  557. if (result < 0)
  558. goto out_shut;
  559. dev_dbg(&ofdev->dev, "hw routines for %s registered.\n",
  560. cpm->adap.name);
  561. return 0;
  562. out_shut:
  563. cpm_i2c_shutdown(cpm);
  564. out_free:
  565. kfree(cpm);
  566. return result;
  567. }
  568. static int cpm_i2c_remove(struct platform_device *ofdev)
  569. {
  570. struct cpm_i2c *cpm = platform_get_drvdata(ofdev);
  571. i2c_del_adapter(&cpm->adap);
  572. cpm_i2c_shutdown(cpm);
  573. kfree(cpm);
  574. return 0;
  575. }
  576. static const struct of_device_id cpm_i2c_match[] = {
  577. {
  578. .compatible = "fsl,cpm1-i2c",
  579. },
  580. {
  581. .compatible = "fsl,cpm2-i2c",
  582. },
  583. {},
  584. };
  585. MODULE_DEVICE_TABLE(of, cpm_i2c_match);
  586. static struct platform_driver cpm_i2c_driver = {
  587. .probe = cpm_i2c_probe,
  588. .remove = cpm_i2c_remove,
  589. .driver = {
  590. .name = "fsl-i2c-cpm",
  591. .of_match_table = cpm_i2c_match,
  592. },
  593. };
  594. module_platform_driver(cpm_i2c_driver);
  595. MODULE_AUTHOR("Jochen Friedrich <jochen@scram.de>");
  596. MODULE_DESCRIPTION("I2C-Bus adapter routines for CPM boards");
  597. MODULE_LICENSE("GPL");