tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Blackfin On-Chip Two Wire Interface Driver
3 *
4 * Copyright 2005-2007 Analog Devices Inc.
5 *
6 * Enter bugs at http://blackfin.uclinux.org/
7 *
8 * Licensed under the GPL-2 or later.
9 */
10
11#include <linux/module.h>
12#include <linux/kernel.h>
13#include <linux/init.h>
14#include <linux/i2c.h>
15#include <linux/slab.h>
16#include <linux/io.h>
17#include <linux/mm.h>
18#include <linux/timer.h>
19#include <linux/spinlock.h>
20#include <linux/completion.h>
21#include <linux/interrupt.h>
22#include <linux/platform_device.h>
23#include <linux/delay.h>
24
25#include <asm/blackfin.h>
26#include <asm/portmux.h>
27#include <asm/irq.h>
28#include <asm/bfin_twi.h>
29
30/* SMBus mode*/
31#define TWI_I2C_MODE_STANDARD 1
32#define TWI_I2C_MODE_STANDARDSUB 2
33#define TWI_I2C_MODE_COMBINED 3
34#define TWI_I2C_MODE_REPEAT 4
35
36static void bfin_twi_handle_interrupt(struct bfin_twi_iface *iface,
37 unsigned short twi_int_status)
38{
39 unsigned short mast_stat = read_MASTER_STAT(iface);
40
41 if (twi_int_status & XMTSERV) {
42 /* Transmit next data */
43 if (iface->writeNum > 0) {
44 SSYNC();
45 write_XMT_DATA8(iface, *(iface->transPtr++));
46 iface->writeNum--;
47 }
48 /* start receive immediately after complete sending in
49 * combine mode.
50 */
51 else if (iface->cur_mode == TWI_I2C_MODE_COMBINED)
52 write_MASTER_CTL(iface,
53 read_MASTER_CTL(iface) | MDIR);
54 else if (iface->manual_stop)
55 write_MASTER_CTL(iface,
56 read_MASTER_CTL(iface) | STOP);
57 else if (iface->cur_mode == TWI_I2C_MODE_REPEAT &&
58 iface->cur_msg + 1 < iface->msg_num) {
59 if (iface->pmsg[iface->cur_msg + 1].flags & I2C_M_RD)
60 write_MASTER_CTL(iface,
61 read_MASTER_CTL(iface) | MDIR);
62 else
63 write_MASTER_CTL(iface,
64 read_MASTER_CTL(iface) & ~MDIR);
65 }
66 }
67 if (twi_int_status & RCVSERV) {
68 if (iface->readNum > 0) {
69 /* Receive next data */
70 *(iface->transPtr) = read_RCV_DATA8(iface);
71 if (iface->cur_mode == TWI_I2C_MODE_COMBINED) {
72 /* Change combine mode into sub mode after
73 * read first data.
74 */
75 iface->cur_mode = TWI_I2C_MODE_STANDARDSUB;
76 /* Get read number from first byte in block
77 * combine mode.
78 */
79 if (iface->readNum == 1 && iface->manual_stop)
80 iface->readNum = *iface->transPtr + 1;
81 }
82 iface->transPtr++;
83 iface->readNum--;
84 }
85
86 if (iface->readNum == 0) {
87 if (iface->manual_stop) {
88 /* Temporary workaround to avoid possible bus stall -
89 * Flush FIFO before issuing the STOP condition
90 */
91 read_RCV_DATA16(iface);
92 write_MASTER_CTL(iface,
93 read_MASTER_CTL(iface) | STOP);
94 } else if (iface->cur_mode == TWI_I2C_MODE_REPEAT &&
95 iface->cur_msg + 1 < iface->msg_num) {
96 if (iface->pmsg[iface->cur_msg + 1].flags & I2C_M_RD)
97 write_MASTER_CTL(iface,
98 read_MASTER_CTL(iface) | MDIR);
99 else
100 write_MASTER_CTL(iface,
101 read_MASTER_CTL(iface) & ~MDIR);
102 }
103 }
104 }
105 if (twi_int_status & MERR) {
106 write_INT_MASK(iface, 0);
107 write_MASTER_STAT(iface, 0x3e);
108 write_MASTER_CTL(iface, 0);
109 iface->result = -EIO;
110
111 if (mast_stat & LOSTARB)
112 dev_dbg(&iface->adap.dev, "Lost Arbitration\n");
113 if (mast_stat & ANAK)
114 dev_dbg(&iface->adap.dev, "Address Not Acknowledged\n");
115 if (mast_stat & DNAK)
116 dev_dbg(&iface->adap.dev, "Data Not Acknowledged\n");
117 if (mast_stat & BUFRDERR)
118 dev_dbg(&iface->adap.dev, "Buffer Read Error\n");
119 if (mast_stat & BUFWRERR)
120 dev_dbg(&iface->adap.dev, "Buffer Write Error\n");
121
122 /* Faulty slave devices, may drive SDA low after a transfer
123 * finishes. To release the bus this code generates up to 9
124 * extra clocks until SDA is released.
125 */
126
127 if (read_MASTER_STAT(iface) & SDASEN) {
128 int cnt = 9;
129 do {
130 write_MASTER_CTL(iface, SCLOVR);
131 udelay(6);
132 write_MASTER_CTL(iface, 0);
133 udelay(6);
134 } while ((read_MASTER_STAT(iface) & SDASEN) && cnt--);
135
136 write_MASTER_CTL(iface, SDAOVR | SCLOVR);
137 udelay(6);
138 write_MASTER_CTL(iface, SDAOVR);
139 udelay(6);
140 write_MASTER_CTL(iface, 0);
141 }
142
143 /* If it is a quick transfer, only address without data,
144 * not an err, return 1.
145 */
146 if (iface->cur_mode == TWI_I2C_MODE_STANDARD &&
147 iface->transPtr == NULL &&
148 (twi_int_status & MCOMP) && (mast_stat & DNAK))
149 iface->result = 1;
150
151 complete(&iface->complete);
152 return;
153 }
154 if (twi_int_status & MCOMP) {
155 if (twi_int_status & (XMTSERV | RCVSERV) &&
156 (read_MASTER_CTL(iface) & MEN) == 0 &&
157 (iface->cur_mode == TWI_I2C_MODE_REPEAT ||
158 iface->cur_mode == TWI_I2C_MODE_COMBINED)) {
159 iface->result = -1;
160 write_INT_MASK(iface, 0);
161 write_MASTER_CTL(iface, 0);
162 } else if (iface->cur_mode == TWI_I2C_MODE_COMBINED) {
163 if (iface->readNum == 0) {
164 /* set the read number to 1 and ask for manual
165 * stop in block combine mode
166 */
167 iface->readNum = 1;
168 iface->manual_stop = 1;
169 write_MASTER_CTL(iface,
170 read_MASTER_CTL(iface) | (0xff << 6));
171 } else {
172 /* set the readd number in other
173 * combine mode.
174 */
175 write_MASTER_CTL(iface,
176 (read_MASTER_CTL(iface) &
177 (~(0xff << 6))) |
178 (iface->readNum << 6));
179 }
180 /* remove restart bit and enable master receive */
181 write_MASTER_CTL(iface,
182 read_MASTER_CTL(iface) & ~RSTART);
183 } else if (iface->cur_mode == TWI_I2C_MODE_REPEAT &&
184 iface->cur_msg + 1 < iface->msg_num) {
185 iface->cur_msg++;
186 iface->transPtr = iface->pmsg[iface->cur_msg].buf;
187 iface->writeNum = iface->readNum =
188 iface->pmsg[iface->cur_msg].len;
189 /* Set Transmit device address */
190 write_MASTER_ADDR(iface,
191 iface->pmsg[iface->cur_msg].addr);
192 if (iface->pmsg[iface->cur_msg].flags & I2C_M_RD)
193 iface->read_write = I2C_SMBUS_READ;
194 else {
195 iface->read_write = I2C_SMBUS_WRITE;
196 /* Transmit first data */
197 if (iface->writeNum > 0) {
198 write_XMT_DATA8(iface,
199 *(iface->transPtr++));
200 iface->writeNum--;
201 }
202 }
203
204 if (iface->pmsg[iface->cur_msg].len <= 255) {
205 write_MASTER_CTL(iface,
206 (read_MASTER_CTL(iface) &
207 (~(0xff << 6))) |
208 (iface->pmsg[iface->cur_msg].len << 6));
209 iface->manual_stop = 0;
210 } else {
211 write_MASTER_CTL(iface,
212 (read_MASTER_CTL(iface) |
213 (0xff << 6)));
214 iface->manual_stop = 1;
215 }
216 /* remove restart bit before last message */
217 if (iface->cur_msg + 1 == iface->msg_num)
218 write_MASTER_CTL(iface,
219 read_MASTER_CTL(iface) & ~RSTART);
220 } else {
221 iface->result = 1;
222 write_INT_MASK(iface, 0);
223 write_MASTER_CTL(iface, 0);
224 }
225 complete(&iface->complete);
226 }
227}
228
229/* Interrupt handler */
230static irqreturn_t bfin_twi_interrupt_entry(int irq, void *dev_id)
231{
232 struct bfin_twi_iface *iface = dev_id;
233 unsigned long flags;
234 unsigned short twi_int_status;
235
236 spin_lock_irqsave(&iface->lock, flags);
237 while (1) {
238 twi_int_status = read_INT_STAT(iface);
239 if (!twi_int_status)
240 break;
241 /* Clear interrupt status */
242 write_INT_STAT(iface, twi_int_status);
243 bfin_twi_handle_interrupt(iface, twi_int_status);
244 SSYNC();
245 }
246 spin_unlock_irqrestore(&iface->lock, flags);
247 return IRQ_HANDLED;
248}
249
250/*
251 * One i2c master transfer
252 */
253static int bfin_twi_do_master_xfer(struct i2c_adapter *adap,
254 struct i2c_msg *msgs, int num)
255{
256 struct bfin_twi_iface *iface = adap->algo_data;
257 struct i2c_msg *pmsg;
258 int rc = 0;
259
260 if (!(read_CONTROL(iface) & TWI_ENA))
261 return -ENXIO;
262
263 if (read_MASTER_STAT(iface) & BUSBUSY)
264 return -EAGAIN;
265
266 iface->pmsg = msgs;
267 iface->msg_num = num;
268 iface->cur_msg = 0;
269
270 pmsg = &msgs[0];
271 if (pmsg->flags & I2C_M_TEN) {
272 dev_err(&adap->dev, "10 bits addr not supported!\n");
273 return -EINVAL;
274 }
275
276 if (iface->msg_num > 1)
277 iface->cur_mode = TWI_I2C_MODE_REPEAT;
278 iface->manual_stop = 0;
279 iface->transPtr = pmsg->buf;
280 iface->writeNum = iface->readNum = pmsg->len;
281 iface->result = 0;
282 init_completion(&(iface->complete));
283 /* Set Transmit device address */
284 write_MASTER_ADDR(iface, pmsg->addr);
285
286 /* FIFO Initiation. Data in FIFO should be
287 * discarded before start a new operation.
288 */
289 write_FIFO_CTL(iface, 0x3);
290 SSYNC();
291 write_FIFO_CTL(iface, 0);
292 SSYNC();
293
294 if (pmsg->flags & I2C_M_RD)
295 iface->read_write = I2C_SMBUS_READ;
296 else {
297 iface->read_write = I2C_SMBUS_WRITE;
298 /* Transmit first data */
299 if (iface->writeNum > 0) {
300 write_XMT_DATA8(iface, *(iface->transPtr++));
301 iface->writeNum--;
302 SSYNC();
303 }
304 }
305
306 /* clear int stat */
307 write_INT_STAT(iface, MERR | MCOMP | XMTSERV | RCVSERV);
308
309 /* Interrupt mask . Enable XMT, RCV interrupt */
310 write_INT_MASK(iface, MCOMP | MERR | RCVSERV | XMTSERV);
311 SSYNC();
312
313 if (pmsg->len <= 255)
314 write_MASTER_CTL(iface, pmsg->len << 6);
315 else {
316 write_MASTER_CTL(iface, 0xff << 6);
317 iface->manual_stop = 1;
318 }
319
320 /* Master enable */
321 write_MASTER_CTL(iface, read_MASTER_CTL(iface) | MEN |
322 (iface->msg_num > 1 ? RSTART : 0) |
323 ((iface->read_write == I2C_SMBUS_READ) ? MDIR : 0) |
324 ((CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ > 100) ? FAST : 0));
325 SSYNC();
326
327 while (!iface->result) {
328 if (!wait_for_completion_timeout(&iface->complete,
329 adap->timeout)) {
330 iface->result = -1;
331 dev_err(&adap->dev, "master transfer timeout\n");
332 }
333 }
334
335 if (iface->result == 1)
336 rc = iface->cur_msg + 1;
337 else
338 rc = iface->result;
339
340 return rc;
341}
342
343/*
344 * Generic i2c master transfer entrypoint
345 */
346static int bfin_twi_master_xfer(struct i2c_adapter *adap,
347 struct i2c_msg *msgs, int num)
348{
349 return bfin_twi_do_master_xfer(adap, msgs, num);
350}
351
352/*
353 * One I2C SMBus transfer
354 */
355int bfin_twi_do_smbus_xfer(struct i2c_adapter *adap, u16 addr,
356 unsigned short flags, char read_write,
357 u8 command, int size, union i2c_smbus_data *data)
358{
359 struct bfin_twi_iface *iface = adap->algo_data;
360 int rc = 0;
361
362 if (!(read_CONTROL(iface) & TWI_ENA))
363 return -ENXIO;
364
365 if (read_MASTER_STAT(iface) & BUSBUSY)
366 return -EAGAIN;
367
368 iface->writeNum = 0;
369 iface->readNum = 0;
370
371 /* Prepare datas & select mode */
372 switch (size) {
373 case I2C_SMBUS_QUICK:
374 iface->transPtr = NULL;
375 iface->cur_mode = TWI_I2C_MODE_STANDARD;
376 break;
377 case I2C_SMBUS_BYTE:
378 if (data == NULL)
379 iface->transPtr = NULL;
380 else {
381 if (read_write == I2C_SMBUS_READ)
382 iface->readNum = 1;
383 else
384 iface->writeNum = 1;
385 iface->transPtr = &data->byte;
386 }
387 iface->cur_mode = TWI_I2C_MODE_STANDARD;
388 break;
389 case I2C_SMBUS_BYTE_DATA:
390 if (read_write == I2C_SMBUS_READ) {
391 iface->readNum = 1;
392 iface->cur_mode = TWI_I2C_MODE_COMBINED;
393 } else {
394 iface->writeNum = 1;
395 iface->cur_mode = TWI_I2C_MODE_STANDARDSUB;
396 }
397 iface->transPtr = &data->byte;
398 break;
399 case I2C_SMBUS_WORD_DATA:
400 if (read_write == I2C_SMBUS_READ) {
401 iface->readNum = 2;
402 iface->cur_mode = TWI_I2C_MODE_COMBINED;
403 } else {
404 iface->writeNum = 2;
405 iface->cur_mode = TWI_I2C_MODE_STANDARDSUB;
406 }
407 iface->transPtr = (u8 *)&data->word;
408 break;
409 case I2C_SMBUS_PROC_CALL:
410 iface->writeNum = 2;
411 iface->readNum = 2;
412 iface->cur_mode = TWI_I2C_MODE_COMBINED;
413 iface->transPtr = (u8 *)&data->word;
414 break;
415 case I2C_SMBUS_BLOCK_DATA:
416 if (read_write == I2C_SMBUS_READ) {
417 iface->readNum = 0;
418 iface->cur_mode = TWI_I2C_MODE_COMBINED;
419 } else {
420 iface->writeNum = data->block[0] + 1;
421 iface->cur_mode = TWI_I2C_MODE_STANDARDSUB;
422 }
423 iface->transPtr = data->block;
424 break;
425 case I2C_SMBUS_I2C_BLOCK_DATA:
426 if (read_write == I2C_SMBUS_READ) {
427 iface->readNum = data->block[0];
428 iface->cur_mode = TWI_I2C_MODE_COMBINED;
429 } else {
430 iface->writeNum = data->block[0];
431 iface->cur_mode = TWI_I2C_MODE_STANDARDSUB;
432 }
433 iface->transPtr = (u8 *)&data->block[1];
434 break;
435 default:
436 return -1;
437 }
438
439 iface->result = 0;
440 iface->manual_stop = 0;
441 iface->read_write = read_write;
442 iface->command = command;
443 init_completion(&(iface->complete));
444
445 /* FIFO Initiation. Data in FIFO should be discarded before
446 * start a new operation.
447 */
448 write_FIFO_CTL(iface, 0x3);
449 SSYNC();
450 write_FIFO_CTL(iface, 0);
451
452 /* clear int stat */
453 write_INT_STAT(iface, MERR | MCOMP | XMTSERV | RCVSERV);
454
455 /* Set Transmit device address */
456 write_MASTER_ADDR(iface, addr);
457 SSYNC();
458
459 switch (iface->cur_mode) {
460 case TWI_I2C_MODE_STANDARDSUB:
461 write_XMT_DATA8(iface, iface->command);
462 write_INT_MASK(iface, MCOMP | MERR |
463 ((iface->read_write == I2C_SMBUS_READ) ?
464 RCVSERV : XMTSERV));
465 SSYNC();
466
467 if (iface->writeNum + 1 <= 255)
468 write_MASTER_CTL(iface, (iface->writeNum + 1) << 6);
469 else {
470 write_MASTER_CTL(iface, 0xff << 6);
471 iface->manual_stop = 1;
472 }
473 /* Master enable */
474 write_MASTER_CTL(iface, read_MASTER_CTL(iface) | MEN |
475 ((CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ>100) ? FAST : 0));
476 break;
477 case TWI_I2C_MODE_COMBINED:
478 write_XMT_DATA8(iface, iface->command);
479 write_INT_MASK(iface, MCOMP | MERR | RCVSERV | XMTSERV);
480 SSYNC();
481
482 if (iface->writeNum > 0)
483 write_MASTER_CTL(iface, (iface->writeNum + 1) << 6);
484 else
485 write_MASTER_CTL(iface, 0x1 << 6);
486 /* Master enable */
487 write_MASTER_CTL(iface, read_MASTER_CTL(iface) | MEN | RSTART |
488 ((CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ>100) ? FAST : 0));
489 break;
490 default:
491 write_MASTER_CTL(iface, 0);
492 if (size != I2C_SMBUS_QUICK) {
493 /* Don't access xmit data register when this is a
494 * read operation.
495 */
496 if (iface->read_write != I2C_SMBUS_READ) {
497 if (iface->writeNum > 0) {
498 write_XMT_DATA8(iface,
499 *(iface->transPtr++));
500 if (iface->writeNum <= 255)
501 write_MASTER_CTL(iface,
502 iface->writeNum << 6);
503 else {
504 write_MASTER_CTL(iface,
505 0xff << 6);
506 iface->manual_stop = 1;
507 }
508 iface->writeNum--;
509 } else {
510 write_XMT_DATA8(iface, iface->command);
511 write_MASTER_CTL(iface, 1 << 6);
512 }
513 } else {
514 if (iface->readNum > 0 && iface->readNum <= 255)
515 write_MASTER_CTL(iface,
516 iface->readNum << 6);
517 else if (iface->readNum > 255) {
518 write_MASTER_CTL(iface, 0xff << 6);
519 iface->manual_stop = 1;
520 } else
521 break;
522 }
523 }
524 write_INT_MASK(iface, MCOMP | MERR |
525 ((iface->read_write == I2C_SMBUS_READ) ?
526 RCVSERV : XMTSERV));
527 SSYNC();
528
529 /* Master enable */
530 write_MASTER_CTL(iface, read_MASTER_CTL(iface) | MEN |
531 ((iface->read_write == I2C_SMBUS_READ) ? MDIR : 0) |
532 ((CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ > 100) ? FAST : 0));
533 break;
534 }
535 SSYNC();
536
537 while (!iface->result) {
538 if (!wait_for_completion_timeout(&iface->complete,
539 adap->timeout)) {
540 iface->result = -1;
541 dev_err(&adap->dev, "smbus transfer timeout\n");
542 }
543 }
544
545 rc = (iface->result >= 0) ? 0 : -1;
546
547 return rc;
548}
549
550/*
551 * Generic I2C SMBus transfer entrypoint
552 */
553int bfin_twi_smbus_xfer(struct i2c_adapter *adap, u16 addr,
554 unsigned short flags, char read_write,
555 u8 command, int size, union i2c_smbus_data *data)
556{
557 return bfin_twi_do_smbus_xfer(adap, addr, flags,
558 read_write, command, size, data);
559}
560
561/*
562 * Return what the adapter supports
563 */
564static u32 bfin_twi_functionality(struct i2c_adapter *adap)
565{
566 return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
567 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
568 I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_PROC_CALL |
569 I2C_FUNC_I2C | I2C_FUNC_SMBUS_I2C_BLOCK;
570}
571
572static struct i2c_algorithm bfin_twi_algorithm = {
573 .master_xfer = bfin_twi_master_xfer,
574 .smbus_xfer = bfin_twi_smbus_xfer,
575 .functionality = bfin_twi_functionality,
576};
577
578static int i2c_bfin_twi_suspend(struct device *dev)
579{
580 struct bfin_twi_iface *iface = dev_get_drvdata(dev);
581
582 iface->saved_clkdiv = read_CLKDIV(iface);
583 iface->saved_control = read_CONTROL(iface);
584
585 free_irq(iface->irq, iface);
586
587 /* Disable TWI */
588 write_CONTROL(iface, iface->saved_control & ~TWI_ENA);
589
590 return 0;
591}
592
593static int i2c_bfin_twi_resume(struct device *dev)
594{
595 struct bfin_twi_iface *iface = dev_get_drvdata(dev);
596
597 int rc = request_irq(iface->irq, bfin_twi_interrupt_entry,
598 0, to_platform_device(dev)->name, iface);
599 if (rc) {
600 dev_err(dev, "Can't get IRQ %d !\n", iface->irq);
601 return -ENODEV;
602 }
603
604 /* Resume TWI interface clock as specified */
605 write_CLKDIV(iface, iface->saved_clkdiv);
606
607 /* Resume TWI */
608 write_CONTROL(iface, iface->saved_control);
609
610 return 0;
611}
612
613static SIMPLE_DEV_PM_OPS(i2c_bfin_twi_pm,
614 i2c_bfin_twi_suspend, i2c_bfin_twi_resume);
615
616static int i2c_bfin_twi_probe(struct platform_device *pdev)
617{
618 struct bfin_twi_iface *iface;
619 struct i2c_adapter *p_adap;
620 struct resource *res;
621 int rc;
622 unsigned int clkhilow;
623
624 iface = kzalloc(sizeof(struct bfin_twi_iface), GFP_KERNEL);
625 if (!iface) {
626 dev_err(&pdev->dev, "Cannot allocate memory\n");
627 rc = -ENOMEM;
628 goto out_error_nomem;
629 }
630
631 spin_lock_init(&(iface->lock));
632
633 /* Find and map our resources */
634 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
635 if (res == NULL) {
636 dev_err(&pdev->dev, "Cannot get IORESOURCE_MEM\n");
637 rc = -ENOENT;
638 goto out_error_get_res;
639 }
640
641 iface->regs_base = ioremap(res->start, resource_size(res));
642 if (iface->regs_base == NULL) {
643 dev_err(&pdev->dev, "Cannot map IO\n");
644 rc = -ENXIO;
645 goto out_error_ioremap;
646 }
647
648 iface->irq = platform_get_irq(pdev, 0);
649 if (iface->irq < 0) {
650 dev_err(&pdev->dev, "No IRQ specified\n");
651 rc = -ENOENT;
652 goto out_error_no_irq;
653 }
654
655 p_adap = &iface->adap;
656 p_adap->nr = pdev->id;
657 strlcpy(p_adap->name, pdev->name, sizeof(p_adap->name));
658 p_adap->algo = &bfin_twi_algorithm;
659 p_adap->algo_data = iface;
660 p_adap->class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
661 p_adap->dev.parent = &pdev->dev;
662 p_adap->timeout = 5 * HZ;
663 p_adap->retries = 3;
664
665 rc = peripheral_request_list((unsigned short *)pdev->dev.platform_data,
666 "i2c-bfin-twi");
667 if (rc) {
668 dev_err(&pdev->dev, "Can't setup pin mux!\n");
669 goto out_error_pin_mux;
670 }
671
672 rc = request_irq(iface->irq, bfin_twi_interrupt_entry,
673 0, pdev->name, iface);
674 if (rc) {
675 dev_err(&pdev->dev, "Can't get IRQ %d !\n", iface->irq);
676 rc = -ENODEV;
677 goto out_error_req_irq;
678 }
679
680 /* Set TWI internal clock as 10MHz */
681 write_CONTROL(iface, ((get_sclk() / 1000 / 1000 + 5) / 10) & 0x7F);
682
683 /*
684 * We will not end up with a CLKDIV=0 because no one will specify
685 * 20kHz SCL or less in Kconfig now. (5 * 1000 / 20 = 250)
686 */
687 clkhilow = ((10 * 1000 / CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ) + 1) / 2;
688
689 /* Set Twi interface clock as specified */
690 write_CLKDIV(iface, (clkhilow << 8) | clkhilow);
691
692 /* Enable TWI */
693 write_CONTROL(iface, read_CONTROL(iface) | TWI_ENA);
694 SSYNC();
695
696 rc = i2c_add_numbered_adapter(p_adap);
697 if (rc < 0) {
698 dev_err(&pdev->dev, "Can't add i2c adapter!\n");
699 goto out_error_add_adapter;
700 }
701
702 platform_set_drvdata(pdev, iface);
703
704 dev_info(&pdev->dev, "Blackfin BF5xx on-chip I2C TWI Contoller, "
705 "regs_base@%p\n", iface->regs_base);
706
707 return 0;
708
709out_error_add_adapter:
710 free_irq(iface->irq, iface);
711out_error_req_irq:
712out_error_no_irq:
713 peripheral_free_list((unsigned short *)pdev->dev.platform_data);
714out_error_pin_mux:
715 iounmap(iface->regs_base);
716out_error_ioremap:
717out_error_get_res:
718 kfree(iface);
719out_error_nomem:
720 return rc;
721}
722
723static int i2c_bfin_twi_remove(struct platform_device *pdev)
724{
725 struct bfin_twi_iface *iface = platform_get_drvdata(pdev);
726
727 platform_set_drvdata(pdev, NULL);
728
729 i2c_del_adapter(&(iface->adap));
730 free_irq(iface->irq, iface);
731 peripheral_free_list((unsigned short *)pdev->dev.platform_data);
732 iounmap(iface->regs_base);
733 kfree(iface);
734
735 return 0;
736}
737
738static struct platform_driver i2c_bfin_twi_driver = {
739 .probe = i2c_bfin_twi_probe,
740 .remove = i2c_bfin_twi_remove,
741 .driver = {
742 .name = "i2c-bfin-twi",
743 .owner = THIS_MODULE,
744 .pm = &i2c_bfin_twi_pm,
745 },
746};
747
748static int __init i2c_bfin_twi_init(void)
749{
750 return platform_driver_register(&i2c_bfin_twi_driver);
751}
752
753static void __exit i2c_bfin_twi_exit(void)
754{
755 platform_driver_unregister(&i2c_bfin_twi_driver);
756}
757
758subsys_initcall(i2c_bfin_twi_init);
759module_exit(i2c_bfin_twi_exit);
760
761MODULE_AUTHOR("Bryan Wu, Sonic Zhang");
762MODULE_DESCRIPTION("Blackfin BF5xx on-chip I2C TWI Contoller Driver");
763MODULE_LICENSE("GPL");
764MODULE_ALIAS("platform:i2c-bfin-twi");