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[ARM] pxa: Gumstix Verdex PCMCIA support
[linux-2.6/verdex.git] / drivers / i2c / busses / i2c-bfin-twi.c
blobb309ac2c3d5cad084785f99ea3ea650713f59acf
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/io.h>
16 #include <linux/mm.h>
17 #include <linux/timer.h>
18 #include <linux/spinlock.h>
19 #include <linux/completion.h>
20 #include <linux/interrupt.h>
21 #include <linux/platform_device.h>
22
23 #include <asm/blackfin.h>
24 #include <asm/portmux.h>
25 #include <asm/irq.h>
26
27 #define POLL_TIMEOUT (2 * HZ)
28
29 /* SMBus mode*/
30 #define TWI_I2C_MODE_STANDARD 1
31 #define TWI_I2C_MODE_STANDARDSUB 2
32 #define TWI_I2C_MODE_COMBINED 3
33 #define TWI_I2C_MODE_REPEAT 4
34
35 struct bfin_twi_iface {
36 int irq;
37 spinlock_t lock;
38 char read_write;
39 u8 command;
40 u8 *transPtr;
41 int readNum;
42 int writeNum;
43 int cur_mode;
44 int manual_stop;
45 int result;
46 int timeout_count;
47 struct timer_list timeout_timer;
48 struct i2c_adapter adap;
49 struct completion complete;
50 struct i2c_msg *pmsg;
51 int msg_num;
52 int cur_msg;
53 u16 saved_clkdiv;
54 u16 saved_control;
55 void __iomem *regs_base;
56 };
57
58
59 #define DEFINE_TWI_REG(reg, off) \
60 static inline u16 read_##reg(struct bfin_twi_iface *iface) \
61 { return bfin_read16(iface->regs_base + (off)); } \
62 static inline void write_##reg(struct bfin_twi_iface *iface, u16 v) \
63 { bfin_write16(iface->regs_base + (off), v); }
64
65 DEFINE_TWI_REG(CLKDIV, 0x00)
66 DEFINE_TWI_REG(CONTROL, 0x04)
67 DEFINE_TWI_REG(SLAVE_CTL, 0x08)
68 DEFINE_TWI_REG(SLAVE_STAT, 0x0C)
69 DEFINE_TWI_REG(SLAVE_ADDR, 0x10)
70 DEFINE_TWI_REG(MASTER_CTL, 0x14)
71 DEFINE_TWI_REG(MASTER_STAT, 0x18)
72 DEFINE_TWI_REG(MASTER_ADDR, 0x1C)
73 DEFINE_TWI_REG(INT_STAT, 0x20)
74 DEFINE_TWI_REG(INT_MASK, 0x24)
75 DEFINE_TWI_REG(FIFO_CTL, 0x28)
76 DEFINE_TWI_REG(FIFO_STAT, 0x2C)
77 DEFINE_TWI_REG(XMT_DATA8, 0x80)
78 DEFINE_TWI_REG(XMT_DATA16, 0x84)
79 DEFINE_TWI_REG(RCV_DATA8, 0x88)
80 DEFINE_TWI_REG(RCV_DATA16, 0x8C)
81
82 static const u16 pin_req[2][3] = {
83 {P_TWI0_SCL, P_TWI0_SDA, 0},
84 {P_TWI1_SCL, P_TWI1_SDA, 0},
85 };
86
87 static void bfin_twi_handle_interrupt(struct bfin_twi_iface *iface)
88 {
89 unsigned short twi_int_status = read_INT_STAT(iface);
90 unsigned short mast_stat = read_MASTER_STAT(iface);
91
92 if (twi_int_status & XMTSERV) {
93 /* Transmit next data */
94 if (iface->writeNum > 0) {
95 write_XMT_DATA8(iface, *(iface->transPtr++));
96 iface->writeNum--;
97 }
98 /* start receive immediately after complete sending in
99 * combine mode.
100 */
101 else if (iface->cur_mode == TWI_I2C_MODE_COMBINED)
102 write_MASTER_CTL(iface,
103 read_MASTER_CTL(iface) | MDIR | RSTART);
104 else if (iface->manual_stop)
105 write_MASTER_CTL(iface,
106 read_MASTER_CTL(iface) | STOP);
107 else if (iface->cur_mode == TWI_I2C_MODE_REPEAT &&
108 iface->cur_msg + 1 < iface->msg_num) {
109 if (iface->pmsg[iface->cur_msg + 1].flags & I2C_M_RD)
110 write_MASTER_CTL(iface,
111 read_MASTER_CTL(iface) | RSTART | MDIR);
112 else
113 write_MASTER_CTL(iface,
114 (read_MASTER_CTL(iface) | RSTART) & ~MDIR);
115 }
116 SSYNC();
117 /* Clear status */
118 write_INT_STAT(iface, XMTSERV);
119 SSYNC();
120 }
121 if (twi_int_status & RCVSERV) {
122 if (iface->readNum > 0) {
123 /* Receive next data */
124 *(iface->transPtr) = read_RCV_DATA8(iface);
125 if (iface->cur_mode == TWI_I2C_MODE_COMBINED) {
126 /* Change combine mode into sub mode after
127 * read first data.
128 */
129 iface->cur_mode = TWI_I2C_MODE_STANDARDSUB;
130 /* Get read number from first byte in block
131 * combine mode.
132 */
133 if (iface->readNum == 1 && iface->manual_stop)
134 iface->readNum = *iface->transPtr + 1;
135 }
136 iface->transPtr++;
137 iface->readNum--;
138 } else if (iface->manual_stop) {
139 write_MASTER_CTL(iface,
140 read_MASTER_CTL(iface) | STOP);
141 SSYNC();
142 } else if (iface->cur_mode == TWI_I2C_MODE_REPEAT &&
143 iface->cur_msg + 1 < iface->msg_num) {
144 if (iface->pmsg[iface->cur_msg + 1].flags & I2C_M_RD)
145 write_MASTER_CTL(iface,
146 read_MASTER_CTL(iface) | RSTART | MDIR);
147 else
148 write_MASTER_CTL(iface,
149 (read_MASTER_CTL(iface) | RSTART) & ~MDIR);
150 SSYNC();
151 }
152 /* Clear interrupt source */
153 write_INT_STAT(iface, RCVSERV);
154 SSYNC();
155 }
156 if (twi_int_status & MERR) {
157 write_INT_STAT(iface, MERR);
158 write_INT_MASK(iface, 0);
159 write_MASTER_STAT(iface, 0x3e);
160 write_MASTER_CTL(iface, 0);
161 SSYNC();
162 iface->result = -EIO;
163 /* if both err and complete int stats are set, return proper
164 * results.
165 */
166 if (twi_int_status & MCOMP) {
167 write_INT_STAT(iface, MCOMP);
168 write_INT_MASK(iface, 0);
169 write_MASTER_CTL(iface, 0);
170 SSYNC();
171 /* If it is a quick transfer, only address bug no data,
172 * not an err, return 1.
173 */
174 if (iface->writeNum == 0 && (mast_stat & BUFRDERR))
175 iface->result = 1;
176 /* If address not acknowledged return -1,
177 * else return 0.
178 */
179 else if (!(mast_stat & ANAK))
180 iface->result = 0;
181 }
182 complete(&iface->complete);
183 return;
184 }
185 if (twi_int_status & MCOMP) {
186 write_INT_STAT(iface, MCOMP);
187 SSYNC();
188 if (iface->cur_mode == TWI_I2C_MODE_COMBINED) {
189 if (iface->readNum == 0) {
190 /* set the read number to 1 and ask for manual
191 * stop in block combine mode
192 */
193 iface->readNum = 1;
194 iface->manual_stop = 1;
195 write_MASTER_CTL(iface,
196 read_MASTER_CTL(iface) | (0xff << 6));
197 } else {
198 /* set the readd number in other
199 * combine mode.
200 */
201 write_MASTER_CTL(iface,
202 (read_MASTER_CTL(iface) &
203 (~(0xff << 6))) |
204 (iface->readNum << 6));
205 }
206 /* remove restart bit and enable master receive */
207 write_MASTER_CTL(iface,
208 read_MASTER_CTL(iface) & ~RSTART);
209 SSYNC();
210 } else if (iface->cur_mode == TWI_I2C_MODE_REPEAT &&
211 iface->cur_msg+1 < iface->msg_num) {
212 iface->cur_msg++;
213 iface->transPtr = iface->pmsg[iface->cur_msg].buf;
214 iface->writeNum = iface->readNum =
215 iface->pmsg[iface->cur_msg].len;
216 /* Set Transmit device address */
217 write_MASTER_ADDR(iface,
218 iface->pmsg[iface->cur_msg].addr);
219 if (iface->pmsg[iface->cur_msg].flags & I2C_M_RD)
220 iface->read_write = I2C_SMBUS_READ;
221 else {
222 iface->read_write = I2C_SMBUS_WRITE;
223 /* Transmit first data */
224 if (iface->writeNum > 0) {
225 write_XMT_DATA8(iface,
226 *(iface->transPtr++));
227 iface->writeNum--;
228 SSYNC();
229 }
230 }
231
232 if (iface->pmsg[iface->cur_msg].len <= 255)
233 write_MASTER_CTL(iface,
234 (read_MASTER_CTL(iface) &
235 (~(0xff << 6))) |
236 (iface->pmsg[iface->cur_msg].len << 6));
237 else {
238 write_MASTER_CTL(iface,
239 (read_MASTER_CTL(iface) |
240 (0xff << 6)));
241 iface->manual_stop = 1;
242 }
243 /* remove restart bit and enable master receive */
244 write_MASTER_CTL(iface,
245 read_MASTER_CTL(iface) & ~RSTART);
246 SSYNC();
247 } else {
248 iface->result = 1;
249 write_INT_MASK(iface, 0);
250 write_MASTER_CTL(iface, 0);
251 SSYNC();
252 complete(&iface->complete);
253 }
254 }
255 }
256
257 /* Interrupt handler */
258 static irqreturn_t bfin_twi_interrupt_entry(int irq, void *dev_id)
259 {
260 struct bfin_twi_iface *iface = dev_id;
261 unsigned long flags;
262
263 spin_lock_irqsave(&iface->lock, flags);
264 del_timer(&iface->timeout_timer);
265 bfin_twi_handle_interrupt(iface);
266 spin_unlock_irqrestore(&iface->lock, flags);
267 return IRQ_HANDLED;
268 }
269
270 static void bfin_twi_timeout(unsigned long data)
271 {
272 struct bfin_twi_iface *iface = (struct bfin_twi_iface *)data;
273 unsigned long flags;
274
275 spin_lock_irqsave(&iface->lock, flags);
276 bfin_twi_handle_interrupt(iface);
277 if (iface->result == 0) {
278 iface->timeout_count--;
279 if (iface->timeout_count > 0) {
280 iface->timeout_timer.expires = jiffies + POLL_TIMEOUT;
281 add_timer(&iface->timeout_timer);
282 } else {
283 iface->result = -1;
284 complete(&iface->complete);
285 }
286 }
287 spin_unlock_irqrestore(&iface->lock, flags);
288 }
289
290 /*
291 * Generic i2c master transfer entrypoint
292 */
293 static int bfin_twi_master_xfer(struct i2c_adapter *adap,
294 struct i2c_msg *msgs, int num)
295 {
296 struct bfin_twi_iface *iface = adap->algo_data;
297 struct i2c_msg *pmsg;
298 int rc = 0;
299
300 if (!(read_CONTROL(iface) & TWI_ENA))
301 return -ENXIO;
302
303 while (read_MASTER_STAT(iface) & BUSBUSY)
304 yield();
305
306 iface->pmsg = msgs;
307 iface->msg_num = num;
308 iface->cur_msg = 0;
309
310 pmsg = &msgs[0];
311 if (pmsg->flags & I2C_M_TEN) {
312 dev_err(&adap->dev, "10 bits addr not supported!\n");
313 return -EINVAL;
314 }
315
316 iface->cur_mode = TWI_I2C_MODE_REPEAT;
317 iface->manual_stop = 0;
318 iface->transPtr = pmsg->buf;
319 iface->writeNum = iface->readNum = pmsg->len;
320 iface->result = 0;
321 iface->timeout_count = 10;
322 init_completion(&(iface->complete));
323 /* Set Transmit device address */
324 write_MASTER_ADDR(iface, pmsg->addr);
325
326 /* FIFO Initiation. Data in FIFO should be
327 * discarded before start a new operation.
328 */
329 write_FIFO_CTL(iface, 0x3);
330 SSYNC();
331 write_FIFO_CTL(iface, 0);
332 SSYNC();
333
334 if (pmsg->flags & I2C_M_RD)
335 iface->read_write = I2C_SMBUS_READ;
336 else {
337 iface->read_write = I2C_SMBUS_WRITE;
338 /* Transmit first data */
339 if (iface->writeNum > 0) {
340 write_XMT_DATA8(iface, *(iface->transPtr++));
341 iface->writeNum--;
342 SSYNC();
343 }
344 }
345
346 /* clear int stat */
347 write_INT_STAT(iface, MERR | MCOMP | XMTSERV | RCVSERV);
348
349 /* Interrupt mask . Enable XMT, RCV interrupt */
350 write_INT_MASK(iface, MCOMP | MERR | RCVSERV | XMTSERV);
351 SSYNC();
352
353 if (pmsg->len <= 255)
354 write_MASTER_CTL(iface, pmsg->len << 6);
355 else {
356 write_MASTER_CTL(iface, 0xff << 6);
357 iface->manual_stop = 1;
358 }
359
360 iface->timeout_timer.expires = jiffies + POLL_TIMEOUT;
361 add_timer(&iface->timeout_timer);
362
363 /* Master enable */
364 write_MASTER_CTL(iface, read_MASTER_CTL(iface) | MEN |
365 ((iface->read_write == I2C_SMBUS_READ) ? MDIR : 0) |
366 ((CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ > 100) ? FAST : 0));
367 SSYNC();
368
369 wait_for_completion(&iface->complete);
370
371 rc = iface->result;
372
373 if (rc == 1)
374 return num;
375 else
376 return rc;
377 }
378
379 /*
380 * SMBus type transfer entrypoint
381 */
382
383 int bfin_twi_smbus_xfer(struct i2c_adapter *adap, u16 addr,
384 unsigned short flags, char read_write,
385 u8 command, int size, union i2c_smbus_data *data)
386 {
387 struct bfin_twi_iface *iface = adap->algo_data;
388 int rc = 0;
389
390 if (!(read_CONTROL(iface) & TWI_ENA))
391 return -ENXIO;
392
393 while (read_MASTER_STAT(iface) & BUSBUSY)
394 yield();
395
396 iface->writeNum = 0;
397 iface->readNum = 0;
398
399 /* Prepare datas & select mode */
400 switch (size) {
401 case I2C_SMBUS_QUICK:
402 iface->transPtr = NULL;
403 iface->cur_mode = TWI_I2C_MODE_STANDARD;
404 break;
405 case I2C_SMBUS_BYTE:
406 if (data == NULL)
407 iface->transPtr = NULL;
408 else {
409 if (read_write == I2C_SMBUS_READ)
410 iface->readNum = 1;
411 else
412 iface->writeNum = 1;
413 iface->transPtr = &data->byte;
414 }
415 iface->cur_mode = TWI_I2C_MODE_STANDARD;
416 break;
417 case I2C_SMBUS_BYTE_DATA:
418 if (read_write == I2C_SMBUS_READ) {
419 iface->readNum = 1;
420 iface->cur_mode = TWI_I2C_MODE_COMBINED;
421 } else {
422 iface->writeNum = 1;
423 iface->cur_mode = TWI_I2C_MODE_STANDARDSUB;
424 }
425 iface->transPtr = &data->byte;
426 break;
427 case I2C_SMBUS_WORD_DATA:
428 if (read_write == I2C_SMBUS_READ) {
429 iface->readNum = 2;
430 iface->cur_mode = TWI_I2C_MODE_COMBINED;
431 } else {
432 iface->writeNum = 2;
433 iface->cur_mode = TWI_I2C_MODE_STANDARDSUB;
434 }
435 iface->transPtr = (u8 *)&data->word;
436 break;
437 case I2C_SMBUS_PROC_CALL:
438 iface->writeNum = 2;
439 iface->readNum = 2;
440 iface->cur_mode = TWI_I2C_MODE_COMBINED;
441 iface->transPtr = (u8 *)&data->word;
442 break;
443 case I2C_SMBUS_BLOCK_DATA:
444 if (read_write == I2C_SMBUS_READ) {
445 iface->readNum = 0;
446 iface->cur_mode = TWI_I2C_MODE_COMBINED;
447 } else {
448 iface->writeNum = data->block[0] + 1;
449 iface->cur_mode = TWI_I2C_MODE_STANDARDSUB;
450 }
451 iface->transPtr = data->block;
452 break;
453 case I2C_SMBUS_I2C_BLOCK_DATA:
454 if (read_write == I2C_SMBUS_READ) {
455 iface->readNum = data->block[0];
456 iface->cur_mode = TWI_I2C_MODE_COMBINED;
457 } else {
458 iface->writeNum = data->block[0];
459 iface->cur_mode = TWI_I2C_MODE_STANDARDSUB;
460 }
461 iface->transPtr = (u8 *)&data->block[1];
462 break;
463 default:
464 return -1;
465 }
466
467 iface->result = 0;
468 iface->manual_stop = 0;
469 iface->read_write = read_write;
470 iface->command = command;
471 iface->timeout_count = 10;
472 init_completion(&(iface->complete));
473
474 /* FIFO Initiation. Data in FIFO should be discarded before
475 * start a new operation.
476 */
477 write_FIFO_CTL(iface, 0x3);
478 SSYNC();
479 write_FIFO_CTL(iface, 0);
480
481 /* clear int stat */
482 write_INT_STAT(iface, MERR | MCOMP | XMTSERV | RCVSERV);
483
484 /* Set Transmit device address */
485 write_MASTER_ADDR(iface, addr);
486 SSYNC();
487
488 iface->timeout_timer.expires = jiffies + POLL_TIMEOUT;
489 add_timer(&iface->timeout_timer);
490
491 switch (iface->cur_mode) {
492 case TWI_I2C_MODE_STANDARDSUB:
493 write_XMT_DATA8(iface, iface->command);
494 write_INT_MASK(iface, MCOMP | MERR |
495 ((iface->read_write == I2C_SMBUS_READ) ?
496 RCVSERV : XMTSERV));
497 SSYNC();
498
499 if (iface->writeNum + 1 <= 255)
500 write_MASTER_CTL(iface, (iface->writeNum + 1) << 6);
501 else {
502 write_MASTER_CTL(iface, 0xff << 6);
503 iface->manual_stop = 1;
504 }
505 /* Master enable */
506 write_MASTER_CTL(iface, read_MASTER_CTL(iface) | MEN |
507 ((CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ>100) ? FAST : 0));
508 break;
509 case TWI_I2C_MODE_COMBINED:
510 write_XMT_DATA8(iface, iface->command);
511 write_INT_MASK(iface, MCOMP | MERR | RCVSERV | XMTSERV);
512 SSYNC();
513
514 if (iface->writeNum > 0)
515 write_MASTER_CTL(iface, (iface->writeNum + 1) << 6);
516 else
517 write_MASTER_CTL(iface, 0x1 << 6);
518 /* Master enable */
519 write_MASTER_CTL(iface, read_MASTER_CTL(iface) | MEN |
520 ((CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ>100) ? FAST : 0));
521 break;
522 default:
523 write_MASTER_CTL(iface, 0);
524 if (size != I2C_SMBUS_QUICK) {
525 /* Don't access xmit data register when this is a
526 * read operation.
527 */
528 if (iface->read_write != I2C_SMBUS_READ) {
529 if (iface->writeNum > 0) {
530 write_XMT_DATA8(iface,
531 *(iface->transPtr++));
532 if (iface->writeNum <= 255)
533 write_MASTER_CTL(iface,
534 iface->writeNum << 6);
535 else {
536 write_MASTER_CTL(iface,
537 0xff << 6);
538 iface->manual_stop = 1;
539 }
540 iface->writeNum--;
541 } else {
542 write_XMT_DATA8(iface, iface->command);
543 write_MASTER_CTL(iface, 1 << 6);
544 }
545 } else {
546 if (iface->readNum > 0 && iface->readNum <= 255)
547 write_MASTER_CTL(iface,
548 iface->readNum << 6);
549 else if (iface->readNum > 255) {
550 write_MASTER_CTL(iface, 0xff << 6);
551 iface->manual_stop = 1;
552 } else {
553 del_timer(&iface->timeout_timer);
554 break;
555 }
556 }
557 }
558 write_INT_MASK(iface, MCOMP | MERR |
559 ((iface->read_write == I2C_SMBUS_READ) ?
560 RCVSERV : XMTSERV));
561 SSYNC();
562
563 /* Master enable */
564 write_MASTER_CTL(iface, read_MASTER_CTL(iface) | MEN |
565 ((iface->read_write == I2C_SMBUS_READ) ? MDIR : 0) |
566 ((CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ > 100) ? FAST : 0));
567 break;
568 }
569 SSYNC();
570
571 wait_for_completion(&iface->complete);
572
573 rc = (iface->result >= 0) ? 0 : -1;
574
575 return rc;
576 }
577
578 /*
579 * Return what the adapter supports
580 */
581 static u32 bfin_twi_functionality(struct i2c_adapter *adap)
582 {
583 return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
584 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
585 I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_PROC_CALL |
586 I2C_FUNC_I2C | I2C_FUNC_SMBUS_I2C_BLOCK;
587 }
588
589 static struct i2c_algorithm bfin_twi_algorithm = {
590 .master_xfer = bfin_twi_master_xfer,
591 .smbus_xfer = bfin_twi_smbus_xfer,
592 .functionality = bfin_twi_functionality,
593 };
594
595 static int i2c_bfin_twi_suspend(struct platform_device *pdev, pm_message_t state)
596 {
597 struct bfin_twi_iface *iface = platform_get_drvdata(pdev);
598
599 iface->saved_clkdiv = read_CLKDIV(iface);
600 iface->saved_control = read_CONTROL(iface);
601
602 free_irq(iface->irq, iface);
603
604 /* Disable TWI */
605 write_CONTROL(iface, iface->saved_control & ~TWI_ENA);
606
607 return 0;
608 }
609
610 static int i2c_bfin_twi_resume(struct platform_device *pdev)
611 {
612 struct bfin_twi_iface *iface = platform_get_drvdata(pdev);
613
614 int rc = request_irq(iface->irq, bfin_twi_interrupt_entry,
615 IRQF_DISABLED, pdev->name, iface);
616 if (rc) {
617 dev_err(&pdev->dev, "Can't get IRQ %d !\n", iface->irq);
618 return -ENODEV;
619 }
620
621 /* Resume TWI interface clock as specified */
622 write_CLKDIV(iface, iface->saved_clkdiv);
623
624 /* Resume TWI */
625 write_CONTROL(iface, iface->saved_control);
626
627 return 0;
628 }
629
630 static int i2c_bfin_twi_probe(struct platform_device *pdev)
631 {
632 struct bfin_twi_iface *iface;
633 struct i2c_adapter *p_adap;
634 struct resource *res;
635 int rc;
636 unsigned int clkhilow;
637
638 iface = kzalloc(sizeof(struct bfin_twi_iface), GFP_KERNEL);
639 if (!iface) {
640 dev_err(&pdev->dev, "Cannot allocate memory\n");
641 rc = -ENOMEM;
642 goto out_error_nomem;
643 }
644
645 spin_lock_init(&(iface->lock));
646
647 /* Find and map our resources */
648 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
649 if (res == NULL) {
650 dev_err(&pdev->dev, "Cannot get IORESOURCE_MEM\n");
651 rc = -ENOENT;
652 goto out_error_get_res;
653 }
654
655 iface->regs_base = ioremap(res->start, resource_size(res));
656 if (iface->regs_base == NULL) {
657 dev_err(&pdev->dev, "Cannot map IO\n");
658 rc = -ENXIO;
659 goto out_error_ioremap;
660 }
661
662 iface->irq = platform_get_irq(pdev, 0);
663 if (iface->irq < 0) {
664 dev_err(&pdev->dev, "No IRQ specified\n");
665 rc = -ENOENT;
666 goto out_error_no_irq;
667 }
668
669 init_timer(&(iface->timeout_timer));
670 iface->timeout_timer.function = bfin_twi_timeout;
671 iface->timeout_timer.data = (unsigned long)iface;
672
673 p_adap = &iface->adap;
674 p_adap->nr = pdev->id;
675 strlcpy(p_adap->name, pdev->name, sizeof(p_adap->name));
676 p_adap->algo = &bfin_twi_algorithm;
677 p_adap->algo_data = iface;
678 p_adap->class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
679 p_adap->dev.parent = &pdev->dev;
680
681 rc = peripheral_request_list(pin_req[pdev->id], "i2c-bfin-twi");
682 if (rc) {
683 dev_err(&pdev->dev, "Can't setup pin mux!\n");
684 goto out_error_pin_mux;
685 }
686
687 rc = request_irq(iface->irq, bfin_twi_interrupt_entry,
688 IRQF_DISABLED, pdev->name, iface);
689 if (rc) {
690 dev_err(&pdev->dev, "Can't get IRQ %d !\n", iface->irq);
691 rc = -ENODEV;
692 goto out_error_req_irq;
693 }
694
695 /* Set TWI internal clock as 10MHz */
696 write_CONTROL(iface, ((get_sclk() / 1024 / 1024 + 5) / 10) & 0x7F);
697
698 /*
699 * We will not end up with a CLKDIV=0 because no one will specify
700 * 20kHz SCL or less in Kconfig now. (5 * 1024 / 20 = 0x100)
701 */
702 clkhilow = 5 * 1024 / CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ;
703
704 /* Set Twi interface clock as specified */
705 write_CLKDIV(iface, (clkhilow << 8) | clkhilow);
706
707 /* Enable TWI */
708 write_CONTROL(iface, read_CONTROL(iface) | TWI_ENA);
709 SSYNC();
710
711 rc = i2c_add_numbered_adapter(p_adap);
712 if (rc < 0) {
713 dev_err(&pdev->dev, "Can't add i2c adapter!\n");
714 goto out_error_add_adapter;
715 }
716
717 platform_set_drvdata(pdev, iface);
718
719 dev_info(&pdev->dev, "Blackfin BF5xx on-chip I2C TWI Contoller, "
720 "regs_base@%p\n", iface->regs_base);
721
722 return 0;
723
724 out_error_add_adapter:
725 free_irq(iface->irq, iface);
726 out_error_req_irq:
727 out_error_no_irq:
728 peripheral_free_list(pin_req[pdev->id]);
729 out_error_pin_mux:
730 iounmap(iface->regs_base);
731 out_error_ioremap:
732 out_error_get_res:
733 kfree(iface);
734 out_error_nomem:
735 return rc;
736 }
737
738 static int i2c_bfin_twi_remove(struct platform_device *pdev)
739 {
740 struct bfin_twi_iface *iface = platform_get_drvdata(pdev);
741
742 platform_set_drvdata(pdev, NULL);
743
744 i2c_del_adapter(&(iface->adap));
745 free_irq(iface->irq, iface);
746 peripheral_free_list(pin_req[pdev->id]);
747 iounmap(iface->regs_base);
748 kfree(iface);
749
750 return 0;
751 }
752
753 static struct platform_driver i2c_bfin_twi_driver = {
754 .probe = i2c_bfin_twi_probe,
755 .remove = i2c_bfin_twi_remove,
756 .suspend = i2c_bfin_twi_suspend,
757 .resume = i2c_bfin_twi_resume,
758 .driver = {
759 .name = "i2c-bfin-twi",
760 .owner = THIS_MODULE,
761 },
762 };
763
764 static int __init i2c_bfin_twi_init(void)
765 {
766 return platform_driver_register(&i2c_bfin_twi_driver);
767 }
768
769 static void __exit i2c_bfin_twi_exit(void)
770 {
771 platform_driver_unregister(&i2c_bfin_twi_driver);
772 }
773
774 module_init(i2c_bfin_twi_init);
775 module_exit(i2c_bfin_twi_exit);
776
777 MODULE_AUTHOR("Bryan Wu, Sonic Zhang");
778 MODULE_DESCRIPTION("Blackfin BF5xx on-chip I2C TWI Contoller Driver");
779 MODULE_LICENSE("GPL");
780 MODULE_ALIAS("platform:i2c-bfin-twi");
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