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Merge branch 'master' of git://git.denx.de/u-boot-cfi-flash
[people/ms/u-boot.git] / drivers / i2c / omap24xx_i2c.c
CommitLineData
8ed96046
WD
1/*
2 * Basic I2C functions
3 *
4 * Copyright (c) 2004 Texas Instruments
5 *
6 * This package is free software; you can redistribute it and/or
7 * modify it under the terms of the license found in the file
8 * named COPYING that should have accompanied this file.
9 *
10 * THIS PACKAGE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
11 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
12 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
13 *
14 * Author: Jian Zhang jzhang@ti.com, Texas Instruments
15 *
16 * Copyright (c) 2003 Wolfgang Denk, wd@denx.de
17 * Rewritten to fit into the current U-Boot framework
18 *
19 * Adapted for OMAP2420 I2C, r-woodruff2@ti.com
20 *
21 */
22
23#include <common.h>
289f932c 24
8ed96046
WD
25#include <asm/arch/i2c.h>
26#include <asm/io.h>
27
938717ce
SS
28#include "omap24xx_i2c.h"
29
29565326
JR
30DECLARE_GLOBAL_DATA_PTR;
31
2faa7619
PR
32#define I2C_STAT_TIMEO (1 << 31)
33#define I2C_TIMEOUT 10
d708395d 34
2faa7619
PR
35static u32 wait_for_bb(void);
36static u32 wait_for_status_mask(u16 mask);
49a7581c 37static void flush_fifo(void);
8ed96046 38
0b620ec9
AM
39/*
40 * For SPL boot some boards need i2c before SDRAM is initialised so force
41 * variables to live in SRAM
42 */
43static struct i2c __attribute__((section (".data"))) *i2c_base =
44 (struct i2c *)I2C_DEFAULT_BASE;
45static unsigned int __attribute__((section (".data"))) bus_initialized[I2C_BUS_MAX] =
46 { [0 ... (I2C_BUS_MAX-1)] = 0 };
47static unsigned int __attribute__((section (".data"))) current_bus = 0;
1d2e96de 48
89677b27 49void i2c_init(int speed, int slaveadd)
8ed96046 50{
7f79dfb4
TR
51 int psc, fsscll, fssclh;
52 int hsscll = 0, hssclh = 0;
53 u32 scll, sclh;
54
55 /* Only handle standard, fast and high speeds */
56 if ((speed != OMAP_I2C_STANDARD) &&
57 (speed != OMAP_I2C_FAST_MODE) &&
58 (speed != OMAP_I2C_HIGH_SPEED)) {
59 printf("Error : I2C unsupported speed %d\n", speed);
60 return;
61 }
62
63 psc = I2C_IP_CLK / I2C_INTERNAL_SAMPLING_CLK;
64 psc -= 1;
65 if (psc < I2C_PSC_MIN) {
66 printf("Error : I2C unsupported prescalar %d\n", psc);
67 return;
68 }
69
70 if (speed == OMAP_I2C_HIGH_SPEED) {
71 /* High speed */
72
73 /* For first phase of HS mode */
74 fsscll = fssclh = I2C_INTERNAL_SAMPLING_CLK /
75 (2 * OMAP_I2C_FAST_MODE);
76
77 fsscll -= I2C_HIGHSPEED_PHASE_ONE_SCLL_TRIM;
78 fssclh -= I2C_HIGHSPEED_PHASE_ONE_SCLH_TRIM;
79 if (((fsscll < 0) || (fssclh < 0)) ||
80 ((fsscll > 255) || (fssclh > 255))) {
49e9b4bd 81 puts("Error : I2C initializing first phase clock\n");
7f79dfb4
TR
82 return;
83 }
84
85 /* For second phase of HS mode */
86 hsscll = hssclh = I2C_INTERNAL_SAMPLING_CLK / (2 * speed);
87
88 hsscll -= I2C_HIGHSPEED_PHASE_TWO_SCLL_TRIM;
89 hssclh -= I2C_HIGHSPEED_PHASE_TWO_SCLH_TRIM;
90 if (((fsscll < 0) || (fssclh < 0)) ||
91 ((fsscll > 255) || (fssclh > 255))) {
49e9b4bd 92 puts("Error : I2C initializing second phase clock\n");
7f79dfb4
TR
93 return;
94 }
95
96 scll = (unsigned int)hsscll << 8 | (unsigned int)fsscll;
97 sclh = (unsigned int)hssclh << 8 | (unsigned int)fssclh;
98
99 } else {
100 /* Standard and fast speed */
101 fsscll = fssclh = I2C_INTERNAL_SAMPLING_CLK / (2 * speed);
102
103 fsscll -= I2C_FASTSPEED_SCLL_TRIM;
104 fssclh -= I2C_FASTSPEED_SCLH_TRIM;
105 if (((fsscll < 0) || (fssclh < 0)) ||
106 ((fsscll > 255) || (fssclh > 255))) {
49e9b4bd 107 puts("Error : I2C initializing clock\n");
7f79dfb4
TR
108 return;
109 }
110
111 scll = (unsigned int)fsscll;
112 sclh = (unsigned int)fssclh;
113 }
8ed96046 114
2faa7619
PR
115 if (gd->flags & GD_FLG_RELOC)
116 bus_initialized[current_bus] = 1;
117
89677b27
MJ
118 if (readw(&i2c_base->con) & I2C_CON_EN) {
119 writew(0, &i2c_base->con);
120 udelay(50000);
8ed96046
WD
121 }
122
1d2e96de
DB
123 writew(psc, &i2c_base->psc);
124 writew(scll, &i2c_base->scll);
125 writew(sclh, &i2c_base->sclh);
7f79dfb4 126
8ed96046 127 /* own address */
89677b27
MJ
128 writew(slaveadd, &i2c_base->oa);
129 writew(I2C_CON_EN, &i2c_base->con);
49a7581c 130
8ed96046 131 /* have to enable intrrupts or OMAP i2c module doesn't work */
89677b27 132 writew(I2C_IE_XRDY_IE | I2C_IE_RRDY_IE | I2C_IE_ARDY_IE |
1d2e96de 133 I2C_IE_NACK_IE | I2C_IE_AL_IE, &i2c_base->ie);
89677b27 134 udelay(1000);
49a7581c 135 flush_fifo();
89677b27
MJ
136 writew(0xFFFF, &i2c_base->stat);
137 writew(0, &i2c_base->cnt);
8ed96046
WD
138}
139
49a7581c 140static void flush_fifo(void)
8ed96046 141{ u16 stat;
082acfd4
WD
142
143 /* note: if you try and read data when its not there or ready
144 * you get a bus error
145 */
89677b27 146 while (1) {
1d2e96de 147 stat = readw(&i2c_base->stat);
89677b27 148 if (stat == I2C_STAT_RRDY) {
938717ce 149#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
498cbdfe 150 defined(CONFIG_OMAP44XX) || defined(CONFIG_AM33XX)
1d2e96de 151 readb(&i2c_base->data);
7d264c1e 152#else
1d2e96de 153 readw(&i2c_base->data);
7d264c1e 154#endif
89677b27 155 writew(I2C_STAT_RRDY, &i2c_base->stat);
8ed96046 156 udelay(1000);
89677b27 157 } else
8ed96046
WD
158 break;
159 }
160}
161
89677b27 162int i2c_probe(uchar chip)
8ed96046 163{
2faa7619 164 u32 status;
8ed96046
WD
165 int res = 1; /* default = fail */
166
89677b27 167 if (chip == readw(&i2c_base->oa))
8ed96046 168 return res;
8ed96046
WD
169
170 /* wait until bus not busy */
2faa7619
PR
171 status = wait_for_bb();
172 /* exit on BUS busy */
173 if (status & I2C_STAT_TIMEO)
174 return res;
8ed96046 175
0e57968a 176 /* try to write one byte */
89677b27 177 writew(1, &i2c_base->cnt);
8ed96046 178 /* set slave address */
89677b27 179 writew(chip, &i2c_base->sa);
8ed96046 180 /* stop bit needed here */
2faa7619
PR
181 writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT
182 | I2C_CON_STP, &i2c_base->con);
183 /* enough delay for the NACK bit set */
184 udelay(9000);
185
186 if (!(readw(&i2c_base->stat) & I2C_STAT_NACK)) {
187 res = 0; /* success case */
188 flush_fifo();
189 writew(0xFFFF, &i2c_base->stat);
190 } else {
191 /* failure, clear sources*/
192 writew(0xFFFF, &i2c_base->stat);
193 /* finish up xfer */
194 writew(readw(&i2c_base->con) | I2C_CON_STP, &i2c_base->con);
195 status = wait_for_bb();
196 /* exit on BUS busy */
197 if (status & I2C_STAT_TIMEO)
198 return res;
199 }
8ed96046 200 flush_fifo();
89677b27
MJ
201 /* don't allow any more data in... we don't want it. */
202 writew(0, &i2c_base->cnt);
1d2e96de 203 writew(0xFFFF, &i2c_base->stat);
8ed96046
WD
204 return res;
205}
206
89677b27 207int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len)
8ed96046 208{
2faa7619
PR
209 int i2c_error = 0, i;
210 u32 status;
211
212 if ((alen > 2) || (alen < 0))
213 return 1;
8ed96046 214
2faa7619
PR
215 if (alen < 2) {
216 if (addr + len > 256)
217 return 1;
218 } else if (addr + len > 0xFFFF) {
8ed96046
WD
219 return 1;
220 }
221
2faa7619
PR
222 /* wait until bus not busy */
223 status = wait_for_bb();
224
225 /* exit on BUS busy */
226 if (status & I2C_STAT_TIMEO)
8ed96046 227 return 1;
2faa7619
PR
228
229 writew((alen & 0xFF), &i2c_base->cnt);
230 /* set slave address */
231 writew(chip, &i2c_base->sa);
232 /* Clear the Tx & Rx FIFOs */
233 writew((readw(&i2c_base->buf) | I2C_RXFIFO_CLEAR |
234 I2C_TXFIFO_CLEAR), &i2c_base->buf);
235 /* no stop bit needed here */
236 writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_TRX |
237 I2C_CON_STT, &i2c_base->con);
238
239 /* wait for Transmit ready condition */
240 status = wait_for_status_mask(I2C_STAT_XRDY | I2C_STAT_NACK);
241
242 if (status & (I2C_STAT_NACK | I2C_STAT_TIMEO))
243 i2c_error = 1;
244
245 if (!i2c_error) {
246 if (status & I2C_STAT_XRDY) {
247 switch (alen) {
248 case 2:
249 /* Send address MSByte */
498cbdfe
PR
250#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
251 defined(CONFIG_AM33XX)
2faa7619
PR
252 writew(((addr >> 8) & 0xFF), &i2c_base->data);
253
254 /* Clearing XRDY event */
255 writew((status & I2C_STAT_XRDY),
256 &i2c_base->stat);
257 /* wait for Transmit ready condition */
258 status = wait_for_status_mask(I2C_STAT_XRDY |
259 I2C_STAT_NACK);
260
261 if (status & (I2C_STAT_NACK |
262 I2C_STAT_TIMEO)) {
263 i2c_error = 1;
264 break;
265 }
266#endif
267 case 1:
498cbdfe
PR
268#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
269 defined(CONFIG_AM33XX)
2faa7619
PR
270 /* Send address LSByte */
271 writew((addr & 0xFF), &i2c_base->data);
272#else
273 /* Send address Short word */
274 writew((addr & 0xFFFF), &i2c_base->data);
275#endif
276 /* Clearing XRDY event */
277 writew((status & I2C_STAT_XRDY),
278 &i2c_base->stat);
279 /*wait for Transmit ready condition */
280 status = wait_for_status_mask(I2C_STAT_ARDY |
281 I2C_STAT_NACK);
282
283 if (status & (I2C_STAT_NACK |
284 I2C_STAT_TIMEO)) {
285 i2c_error = 1;
286 break;
287 }
288 }
289 } else
290 i2c_error = 1;
8ed96046
WD
291 }
292
2faa7619
PR
293 /* Wait for ARDY to set */
294 status = wait_for_status_mask(I2C_STAT_ARDY | I2C_STAT_NACK
295 | I2C_STAT_AL);
296
297 if (!i2c_error) {
298 /* set slave address */
299 writew(chip, &i2c_base->sa);
300 writew((len & 0xFF), &i2c_base->cnt);
301 /* Clear the Tx & Rx FIFOs */
302 writew((readw(&i2c_base->buf) | I2C_RXFIFO_CLEAR |
303 I2C_TXFIFO_CLEAR), &i2c_base->buf);
304 /* need stop bit here */
305 writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_STP,
306 &i2c_base->con);
307
308 for (i = 0; i < len; i++) {
309 /* wait for Receive condition */
310 status = wait_for_status_mask(I2C_STAT_RRDY |
311 I2C_STAT_NACK);
312 if (status & (I2C_STAT_NACK | I2C_STAT_TIMEO)) {
313 i2c_error = 1;
314 break;
315 }
316
317 if (status & I2C_STAT_RRDY) {
498cbdfe
PR
318#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
319 defined(CONFIG_AM33XX)
2faa7619
PR
320 buffer[i] = readb(&i2c_base->data);
321#else
322 *((u16 *)&buffer[i]) =
323 readw(&i2c_base->data) & 0xFFFF;
324 i++;
325#endif
326 writew((status & I2C_STAT_RRDY),
327 &i2c_base->stat);
328 udelay(1000);
329 } else {
330 i2c_error = 1;
331 }
8ed96046
WD
332 }
333 }
334
2faa7619
PR
335 /* Wait for ARDY to set */
336 status = wait_for_status_mask(I2C_STAT_ARDY | I2C_STAT_NACK
337 | I2C_STAT_AL);
338
339 if (i2c_error) {
340 writew(0, &i2c_base->con);
341 return 1;
342 }
343
344 writew(I2C_CON_EN, &i2c_base->con);
345
346 while (readw(&i2c_base->stat)
347 || (readw(&i2c_base->con) & I2C_CON_MST)) {
348 udelay(10000);
349 writew(0xFFFF, &i2c_base->stat);
350 }
351
352 writew(I2C_CON_EN, &i2c_base->con);
353 flush_fifo();
354 writew(0xFFFF, &i2c_base->stat);
355 writew(0, &i2c_base->cnt);
356
8ed96046
WD
357 return 0;
358}
359
89677b27 360int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len)
8ed96046 361{
8ed96046 362
2faa7619
PR
363 int i, i2c_error = 0;
364 u32 status;
365 u16 writelen;
366
367 if (alen > 2)
8ed96046 368 return 1;
8ed96046 369
2faa7619
PR
370 if (alen < 2) {
371 if (addr + len > 256)
372 return 1;
373 } else if (addr + len > 0xFFFF) {
8ed96046
WD
374 return 1;
375 }
376
0607e2b9 377 /* wait until bus not busy */
2faa7619
PR
378 status = wait_for_bb();
379
380 /* exiting on BUS busy */
381 if (status & I2C_STAT_TIMEO)
382 return 1;
0607e2b9 383
2faa7619
PR
384 writelen = (len & 0xFFFF) + alen;
385
386 /* two bytes */
387 writew((writelen & 0xFFFF), &i2c_base->cnt);
388 /* Clear the Tx & Rx FIFOs */
389 writew((readw(&i2c_base->buf) | I2C_RXFIFO_CLEAR |
390 I2C_TXFIFO_CLEAR), &i2c_base->buf);
0607e2b9
MJ
391 /* set slave address */
392 writew(chip, &i2c_base->sa);
393 /* stop bit needed here */
394 writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_TRX |
395 I2C_CON_STP, &i2c_base->con);
396
2faa7619
PR
397 /* wait for Transmit ready condition */
398 status = wait_for_status_mask(I2C_STAT_XRDY | I2C_STAT_NACK);
0607e2b9 399
2faa7619 400 if (status & (I2C_STAT_NACK | I2C_STAT_TIMEO))
0607e2b9 401 i2c_error = 1;
0607e2b9 402
2faa7619
PR
403 if (!i2c_error) {
404 if (status & I2C_STAT_XRDY) {
405 switch (alen) {
498cbdfe
PR
406#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
407 defined(CONFIG_AM33XX)
2faa7619
PR
408 case 2:
409 /* send out MSB byte */
410 writeb(((addr >> 8) & 0xFF), &i2c_base->data);
411#else
412 writeb((addr & 0xFFFF), &i2c_base->data);
413 break;
414#endif
415 /* Clearing XRDY event */
416 writew((status & I2C_STAT_XRDY),
417 &i2c_base->stat);
418 /*waiting for Transmit ready * condition */
419 status = wait_for_status_mask(I2C_STAT_XRDY |
420 I2C_STAT_NACK);
421
422 if (status & (I2C_STAT_NACK | I2C_STAT_TIMEO)) {
423 i2c_error = 1;
424 break;
425 }
426 case 1:
498cbdfe
PR
427#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
428 defined(CONFIG_AM33XX)
2faa7619
PR
429 /* send out MSB byte */
430 writeb((addr & 0xFF), &i2c_base->data);
431#else
432 writew(((buffer[0] << 8) | (addr & 0xFF)),
433 &i2c_base->data);
434#endif
435 }
0607e2b9 436
2faa7619
PR
437 /* Clearing XRDY event */
438 writew((status & I2C_STAT_XRDY), &i2c_base->stat);
439 }
440
441 /* waiting for Transmit ready condition */
442 status = wait_for_status_mask(I2C_STAT_XRDY | I2C_STAT_NACK);
0607e2b9 443
2faa7619 444 if (status & (I2C_STAT_NACK | I2C_STAT_TIMEO))
0607e2b9 445 i2c_error = 1;
2faa7619
PR
446
447 if (!i2c_error) {
448 for (i = ((alen > 1) ? 0 : 1); i < len; i++) {
449 if (status & I2C_STAT_XRDY) {
498cbdfe
PR
450#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
451 defined(CONFIG_AM33XX)
2faa7619
PR
452 writeb((buffer[i] & 0xFF),
453 &i2c_base->data);
454#else
455 writew((((buffer[i] << 8) |
456 buffer[i + 1]) & 0xFFFF),
457 &i2c_base->data);
458 i++;
459#endif
460 } else
461 i2c_error = 1;
462 /* Clearing XRDY event */
463 writew((status & I2C_STAT_XRDY),
464 &i2c_base->stat);
465 /* waiting for XRDY condition */
466 status = wait_for_status_mask(
467 I2C_STAT_XRDY |
468 I2C_STAT_ARDY |
469 I2C_STAT_NACK);
470 if (status & (I2C_STAT_NACK |
471 I2C_STAT_TIMEO)) {
472 i2c_error = 1;
473 break;
474 }
475 if (status & I2C_STAT_ARDY)
476 break;
477 }
0607e2b9 478 }
2faa7619 479 }
0607e2b9 480
2faa7619
PR
481 status = wait_for_status_mask(I2C_STAT_ARDY | I2C_STAT_NACK |
482 I2C_STAT_AL);
483
484 if (status & (I2C_STAT_NACK | I2C_STAT_TIMEO))
485 i2c_error = 1;
486
487 if (i2c_error) {
488 writew(0, &i2c_base->con);
489 return 1;
490 }
491
492 if (!i2c_error) {
493 int eout = 200;
494
495 writew(I2C_CON_EN, &i2c_base->con);
496 while ((status = readw(&i2c_base->stat)) ||
497 (readw(&i2c_base->con) & I2C_CON_MST)) {
498 udelay(1000);
499 /* have to read to clear intrrupt */
500 writew(0xFFFF, &i2c_base->stat);
501 if (--eout == 0)
502 /* better leave with error than hang */
503 break;
8ed96046
WD
504 }
505 }
506
0607e2b9
MJ
507 flush_fifo();
508 writew(0xFFFF, &i2c_base->stat);
2faa7619
PR
509 writew(0, &i2c_base->cnt);
510 return 0;
8ed96046
WD
511}
512
2faa7619 513static u32 wait_for_bb(void)
8ed96046 514{
73e8747f 515 int timeout = I2C_TIMEOUT;
2faa7619 516 u32 stat;
8ed96046 517
89677b27
MJ
518 while ((stat = readw(&i2c_base->stat) & I2C_STAT_BB) && timeout--) {
519 writew(stat, &i2c_base->stat);
73e8747f 520 udelay(1000);
8ed96046
WD
521 }
522
523 if (timeout <= 0) {
89677b27
MJ
524 printf("timed out in wait_for_bb: I2C_STAT=%x\n",
525 readw(&i2c_base->stat));
2faa7619 526 stat |= I2C_STAT_TIMEO;
8ed96046 527 }
1d2e96de 528 writew(0xFFFF, &i2c_base->stat); /* clear delayed stuff*/
2faa7619 529 return stat;
8ed96046
WD
530}
531
2faa7619 532static u32 wait_for_status_mask(u16 mask)
8ed96046 533{
2faa7619 534 u32 status;
73e8747f 535 int timeout = I2C_TIMEOUT;
8ed96046
WD
536
537 do {
89677b27
MJ
538 udelay(1000);
539 status = readw(&i2c_base->stat);
2faa7619 540 } while (!(status & mask) && timeout--);
8ed96046
WD
541
542 if (timeout <= 0) {
2faa7619 543 printf("timed out in wait_for_status_mask: I2C_STAT=%x\n",
89677b27 544 readw(&i2c_base->stat));
73e8747f 545 writew(0xFFFF, &i2c_base->stat);
2faa7619 546 status |= I2C_STAT_TIMEO;
73e8747f 547 }
8ed96046
WD
548 return status;
549}
1d2e96de
DB
550
551int i2c_set_bus_num(unsigned int bus)
552{
553 if ((bus < 0) || (bus >= I2C_BUS_MAX)) {
554 printf("Bad bus: %d\n", bus);
555 return -1;
556 }
557
89677b27 558#if I2C_BUS_MAX == 3
1d2e96de
DB
559 if (bus == 2)
560 i2c_base = (struct i2c *)I2C_BASE3;
561 else
562#endif
563 if (bus == 1)
564 i2c_base = (struct i2c *)I2C_BASE2;
565 else
566 i2c_base = (struct i2c *)I2C_BASE1;
567
568 current_bus = bus;
569
89677b27 570 if (!bus_initialized[current_bus])
1d2e96de
DB
571 i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
572
573 return 0;
574}
938717ce
SS
575
576int i2c_get_bus_num(void)
577{
578 return (int) current_bus;
579}