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Linux 2.6.26-rc5
[linux-2.6/openmoko-kernel/knife-kernel.git] / drivers / i2c / busses / i2c-bfin-twi.c
blob48d084bdf7c8e1d590b18130882c39bc44e3d038
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/mm.h>
16 #include <linux/timer.h>
17 #include <linux/spinlock.h>
18 #include <linux/completion.h>
19 #include <linux/interrupt.h>
20 #include <linux/platform_device.h>
21
22 #include <asm/blackfin.h>
23 #include <asm/portmux.h>
24 #include <asm/irq.h>
25
26 #define POLL_TIMEOUT (2 * HZ)
27
28 /* SMBus mode*/
29 #define TWI_I2C_MODE_STANDARD 1
30 #define TWI_I2C_MODE_STANDARDSUB 2
31 #define TWI_I2C_MODE_COMBINED 3
32 #define TWI_I2C_MODE_REPEAT 4
33
34 struct bfin_twi_iface {
35 int irq;
36 spinlock_t lock;
37 char read_write;
38 u8 command;
39 u8 *transPtr;
40 int readNum;
41 int writeNum;
42 int cur_mode;
43 int manual_stop;
44 int result;
45 int timeout_count;
46 struct timer_list timeout_timer;
47 struct i2c_adapter adap;
48 struct completion complete;
49 struct i2c_msg *pmsg;
50 int msg_num;
51 int cur_msg;
52 void __iomem *regs_base;
53 };
54
55
56 #define DEFINE_TWI_REG(reg, off) \
57 static inline u16 read_##reg(struct bfin_twi_iface *iface) \
58 { return bfin_read16(iface->regs_base + (off)); } \
59 static inline void write_##reg(struct bfin_twi_iface *iface, u16 v) \
60 { bfin_write16(iface->regs_base + (off), v); }
61
62 DEFINE_TWI_REG(CLKDIV, 0x00)
63 DEFINE_TWI_REG(CONTROL, 0x04)
64 DEFINE_TWI_REG(SLAVE_CTL, 0x08)
65 DEFINE_TWI_REG(SLAVE_STAT, 0x0C)
66 DEFINE_TWI_REG(SLAVE_ADDR, 0x10)
67 DEFINE_TWI_REG(MASTER_CTL, 0x14)
68 DEFINE_TWI_REG(MASTER_STAT, 0x18)
69 DEFINE_TWI_REG(MASTER_ADDR, 0x1C)
70 DEFINE_TWI_REG(INT_STAT, 0x20)
71 DEFINE_TWI_REG(INT_MASK, 0x24)
72 DEFINE_TWI_REG(FIFO_CTL, 0x28)
73 DEFINE_TWI_REG(FIFO_STAT, 0x2C)
74 DEFINE_TWI_REG(XMT_DATA8, 0x80)
75 DEFINE_TWI_REG(XMT_DATA16, 0x84)
76 DEFINE_TWI_REG(RCV_DATA8, 0x88)
77 DEFINE_TWI_REG(RCV_DATA16, 0x8C)
78
79 static const u16 pin_req[2][3] = {
80 {P_TWI0_SCL, P_TWI0_SDA, 0},
81 {P_TWI1_SCL, P_TWI1_SDA, 0},
82 };
83
84 static void bfin_twi_handle_interrupt(struct bfin_twi_iface *iface)
85 {
86 unsigned short twi_int_status = read_INT_STAT(iface);
87 unsigned short mast_stat = read_MASTER_STAT(iface);
88
89 if (twi_int_status & XMTSERV) {
90 /* Transmit next data */
91 if (iface->writeNum > 0) {
92 write_XMT_DATA8(iface, *(iface->transPtr++));
93 iface->writeNum--;
94 }
95 /* start receive immediately after complete sending in
96 * combine mode.
97 */
98 else if (iface->cur_mode == TWI_I2C_MODE_COMBINED)
99 write_MASTER_CTL(iface,
100 read_MASTER_CTL(iface) | MDIR | RSTART);
101 else if (iface->manual_stop)
102 write_MASTER_CTL(iface,
103 read_MASTER_CTL(iface) | STOP);
104 else if (iface->cur_mode == TWI_I2C_MODE_REPEAT &&
105 iface->cur_msg+1 < iface->msg_num)
106 write_MASTER_CTL(iface,
107 read_MASTER_CTL(iface) | RSTART);
108 SSYNC();
109 /* Clear status */
110 write_INT_STAT(iface, XMTSERV);
111 SSYNC();
112 }
113 if (twi_int_status & RCVSERV) {
114 if (iface->readNum > 0) {
115 /* Receive next data */
116 *(iface->transPtr) = read_RCV_DATA8(iface);
117 if (iface->cur_mode == TWI_I2C_MODE_COMBINED) {
118 /* Change combine mode into sub mode after
119 * read first data.
120 */
121 iface->cur_mode = TWI_I2C_MODE_STANDARDSUB;
122 /* Get read number from first byte in block
123 * combine mode.
124 */
125 if (iface->readNum == 1 && iface->manual_stop)
126 iface->readNum = *iface->transPtr + 1;
127 }
128 iface->transPtr++;
129 iface->readNum--;
130 } else if (iface->manual_stop) {
131 write_MASTER_CTL(iface,
132 read_MASTER_CTL(iface) | STOP);
133 SSYNC();
134 } else if (iface->cur_mode == TWI_I2C_MODE_REPEAT &&
135 iface->cur_msg+1 < iface->msg_num) {
136 write_MASTER_CTL(iface,
137 read_MASTER_CTL(iface) | RSTART);
138 SSYNC();
139 }
140 /* Clear interrupt source */
141 write_INT_STAT(iface, RCVSERV);
142 SSYNC();
143 }
144 if (twi_int_status & MERR) {
145 write_INT_STAT(iface, MERR);
146 write_INT_MASK(iface, 0);
147 write_MASTER_STAT(iface, 0x3e);
148 write_MASTER_CTL(iface, 0);
149 SSYNC();
150 iface->result = -EIO;
151 /* if both err and complete int stats are set, return proper
152 * results.
153 */
154 if (twi_int_status & MCOMP) {
155 write_INT_STAT(iface, MCOMP);
156 write_INT_MASK(iface, 0);
157 write_MASTER_CTL(iface, 0);
158 SSYNC();
159 /* If it is a quick transfer, only address bug no data,
160 * not an err, return 1.
161 */
162 if (iface->writeNum == 0 && (mast_stat & BUFRDERR))
163 iface->result = 1;
164 /* If address not acknowledged return -1,
165 * else return 0.
166 */
167 else if (!(mast_stat & ANAK))
168 iface->result = 0;
169 }
170 complete(&iface->complete);
171 return;
172 }
173 if (twi_int_status & MCOMP) {
174 write_INT_STAT(iface, MCOMP);
175 SSYNC();
176 if (iface->cur_mode == TWI_I2C_MODE_COMBINED) {
177 if (iface->readNum == 0) {
178 /* set the read number to 1 and ask for manual
179 * stop in block combine mode
180 */
181 iface->readNum = 1;
182 iface->manual_stop = 1;
183 write_MASTER_CTL(iface,
184 read_MASTER_CTL(iface) | (0xff << 6));
185 } else {
186 /* set the readd number in other
187 * combine mode.
188 */
189 write_MASTER_CTL(iface,
190 (read_MASTER_CTL(iface) &
191 (~(0xff << 6))) |
192 (iface->readNum << 6));
193 }
194 /* remove restart bit and enable master receive */
195 write_MASTER_CTL(iface,
196 read_MASTER_CTL(iface) & ~RSTART);
197 write_MASTER_CTL(iface,
198 read_MASTER_CTL(iface) | MEN | MDIR);
199 SSYNC();
200 } else if (iface->cur_mode == TWI_I2C_MODE_REPEAT &&
201 iface->cur_msg+1 < iface->msg_num) {
202 iface->cur_msg++;
203 iface->transPtr = iface->pmsg[iface->cur_msg].buf;
204 iface->writeNum = iface->readNum =
205 iface->pmsg[iface->cur_msg].len;
206 /* Set Transmit device address */
207 write_MASTER_ADDR(iface,
208 iface->pmsg[iface->cur_msg].addr);
209 if (iface->pmsg[iface->cur_msg].flags & I2C_M_RD)
210 iface->read_write = I2C_SMBUS_READ;
211 else {
212 iface->read_write = I2C_SMBUS_WRITE;
213 /* Transmit first data */
214 if (iface->writeNum > 0) {
215 write_XMT_DATA8(iface,
216 *(iface->transPtr++));
217 iface->writeNum--;
218 SSYNC();
219 }
220 }
221
222 if (iface->pmsg[iface->cur_msg].len <= 255)
223 write_MASTER_CTL(iface,
224 iface->pmsg[iface->cur_msg].len << 6);
225 else {
226 write_MASTER_CTL(iface, 0xff << 6);
227 iface->manual_stop = 1;
228 }
229 /* remove restart bit and enable master receive */
230 write_MASTER_CTL(iface,
231 read_MASTER_CTL(iface) & ~RSTART);
232 write_MASTER_CTL(iface, read_MASTER_CTL(iface) |
233 MEN | ((iface->read_write == I2C_SMBUS_READ) ?
234 MDIR : 0));
235 SSYNC();
236 } else {
237 iface->result = 1;
238 write_INT_MASK(iface, 0);
239 write_MASTER_CTL(iface, 0);
240 SSYNC();
241 complete(&iface->complete);
242 }
243 }
244 }
245
246 /* Interrupt handler */
247 static irqreturn_t bfin_twi_interrupt_entry(int irq, void *dev_id)
248 {
249 struct bfin_twi_iface *iface = dev_id;
250 unsigned long flags;
251
252 spin_lock_irqsave(&iface->lock, flags);
253 del_timer(&iface->timeout_timer);
254 bfin_twi_handle_interrupt(iface);
255 spin_unlock_irqrestore(&iface->lock, flags);
256 return IRQ_HANDLED;
257 }
258
259 static void bfin_twi_timeout(unsigned long data)
260 {
261 struct bfin_twi_iface *iface = (struct bfin_twi_iface *)data;
262 unsigned long flags;
263
264 spin_lock_irqsave(&iface->lock, flags);
265 bfin_twi_handle_interrupt(iface);
266 if (iface->result == 0) {
267 iface->timeout_count--;
268 if (iface->timeout_count > 0) {
269 iface->timeout_timer.expires = jiffies + POLL_TIMEOUT;
270 add_timer(&iface->timeout_timer);
271 } else {
272 iface->result = -1;
273 complete(&iface->complete);
274 }
275 }
276 spin_unlock_irqrestore(&iface->lock, flags);
277 }
278
279 /*
280 * Generic i2c master transfer entrypoint
281 */
282 static int bfin_twi_master_xfer(struct i2c_adapter *adap,
283 struct i2c_msg *msgs, int num)
284 {
285 struct bfin_twi_iface *iface = adap->algo_data;
286 struct i2c_msg *pmsg;
287 int rc = 0;
288
289 if (!(read_CONTROL(iface) & TWI_ENA))
290 return -ENXIO;
291
292 while (read_MASTER_STAT(iface) & BUSBUSY)
293 yield();
294
295 iface->pmsg = msgs;
296 iface->msg_num = num;
297 iface->cur_msg = 0;
298
299 pmsg = &msgs[0];
300 if (pmsg->flags & I2C_M_TEN) {
301 dev_err(&adap->dev, "10 bits addr not supported!\n");
302 return -EINVAL;
303 }
304
305 iface->cur_mode = TWI_I2C_MODE_REPEAT;
306 iface->manual_stop = 0;
307 iface->transPtr = pmsg->buf;
308 iface->writeNum = iface->readNum = pmsg->len;
309 iface->result = 0;
310 iface->timeout_count = 10;
311 init_completion(&(iface->complete));
312 /* Set Transmit device address */
313 write_MASTER_ADDR(iface, pmsg->addr);
314
315 /* FIFO Initiation. Data in FIFO should be
316 * discarded before start a new operation.
317 */
318 write_FIFO_CTL(iface, 0x3);
319 SSYNC();
320 write_FIFO_CTL(iface, 0);
321 SSYNC();
322
323 if (pmsg->flags & I2C_M_RD)
324 iface->read_write = I2C_SMBUS_READ;
325 else {
326 iface->read_write = I2C_SMBUS_WRITE;
327 /* Transmit first data */
328 if (iface->writeNum > 0) {
329 write_XMT_DATA8(iface, *(iface->transPtr++));
330 iface->writeNum--;
331 SSYNC();
332 }
333 }
334
335 /* clear int stat */
336 write_INT_STAT(iface, MERR | MCOMP | XMTSERV | RCVSERV);
337
338 /* Interrupt mask . Enable XMT, RCV interrupt */
339 write_INT_MASK(iface, MCOMP | MERR | RCVSERV | XMTSERV);
340 SSYNC();
341
342 if (pmsg->len <= 255)
343 write_MASTER_CTL(iface, pmsg->len << 6);
344 else {
345 write_MASTER_CTL(iface, 0xff << 6);
346 iface->manual_stop = 1;
347 }
348
349 iface->timeout_timer.expires = jiffies + POLL_TIMEOUT;
350 add_timer(&iface->timeout_timer);
351
352 /* Master enable */
353 write_MASTER_CTL(iface, read_MASTER_CTL(iface) | MEN |
354 ((iface->read_write == I2C_SMBUS_READ) ? MDIR : 0) |
355 ((CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ > 100) ? FAST : 0));
356 SSYNC();
357
358 wait_for_completion(&iface->complete);
359
360 rc = iface->result;
361
362 if (rc == 1)
363 return num;
364 else
365 return rc;
366 }
367
368 /*
369 * SMBus type transfer entrypoint
370 */
371
372 int bfin_twi_smbus_xfer(struct i2c_adapter *adap, u16 addr,
373 unsigned short flags, char read_write,
374 u8 command, int size, union i2c_smbus_data *data)
375 {
376 struct bfin_twi_iface *iface = adap->algo_data;
377 int rc = 0;
378
379 if (!(read_CONTROL(iface) & TWI_ENA))
380 return -ENXIO;
381
382 while (read_MASTER_STAT(iface) & BUSBUSY)
383 yield();
384
385 iface->writeNum = 0;
386 iface->readNum = 0;
387
388 /* Prepare datas & select mode */
389 switch (size) {
390 case I2C_SMBUS_QUICK:
391 iface->transPtr = NULL;
392 iface->cur_mode = TWI_I2C_MODE_STANDARD;
393 break;
394 case I2C_SMBUS_BYTE:
395 if (data == NULL)
396 iface->transPtr = NULL;
397 else {
398 if (read_write == I2C_SMBUS_READ)
399 iface->readNum = 1;
400 else
401 iface->writeNum = 1;
402 iface->transPtr = &data->byte;
403 }
404 iface->cur_mode = TWI_I2C_MODE_STANDARD;
405 break;
406 case I2C_SMBUS_BYTE_DATA:
407 if (read_write == I2C_SMBUS_READ) {
408 iface->readNum = 1;
409 iface->cur_mode = TWI_I2C_MODE_COMBINED;
410 } else {
411 iface->writeNum = 1;
412 iface->cur_mode = TWI_I2C_MODE_STANDARDSUB;
413 }
414 iface->transPtr = &data->byte;
415 break;
416 case I2C_SMBUS_WORD_DATA:
417 if (read_write == I2C_SMBUS_READ) {
418 iface->readNum = 2;
419 iface->cur_mode = TWI_I2C_MODE_COMBINED;
420 } else {
421 iface->writeNum = 2;
422 iface->cur_mode = TWI_I2C_MODE_STANDARDSUB;
423 }
424 iface->transPtr = (u8 *)&data->word;
425 break;
426 case I2C_SMBUS_PROC_CALL:
427 iface->writeNum = 2;
428 iface->readNum = 2;
429 iface->cur_mode = TWI_I2C_MODE_COMBINED;
430 iface->transPtr = (u8 *)&data->word;
431 break;
432 case I2C_SMBUS_BLOCK_DATA:
433 if (read_write == I2C_SMBUS_READ) {
434 iface->readNum = 0;
435 iface->cur_mode = TWI_I2C_MODE_COMBINED;
436 } else {
437 iface->writeNum = data->block[0] + 1;
438 iface->cur_mode = TWI_I2C_MODE_STANDARDSUB;
439 }
440 iface->transPtr = data->block;
441 break;
442 default:
443 return -1;
444 }
445
446 iface->result = 0;
447 iface->manual_stop = 0;
448 iface->read_write = read_write;
449 iface->command = command;
450 iface->timeout_count = 10;
451 init_completion(&(iface->complete));
452
453 /* FIFO Initiation. Data in FIFO should be discarded before
454 * start a new operation.
455 */
456 write_FIFO_CTL(iface, 0x3);
457 SSYNC();
458 write_FIFO_CTL(iface, 0);
459
460 /* clear int stat */
461 write_INT_STAT(iface, MERR | MCOMP | XMTSERV | RCVSERV);
462
463 /* Set Transmit device address */
464 write_MASTER_ADDR(iface, addr);
465 SSYNC();
466
467 iface->timeout_timer.expires = jiffies + POLL_TIMEOUT;
468 add_timer(&iface->timeout_timer);
469
470 switch (iface->cur_mode) {
471 case TWI_I2C_MODE_STANDARDSUB:
472 write_XMT_DATA8(iface, iface->command);
473 write_INT_MASK(iface, MCOMP | MERR |
474 ((iface->read_write == I2C_SMBUS_READ) ?
475 RCVSERV : XMTSERV));
476 SSYNC();
477
478 if (iface->writeNum + 1 <= 255)
479 write_MASTER_CTL(iface, (iface->writeNum + 1) << 6);
480 else {
481 write_MASTER_CTL(iface, 0xff << 6);
482 iface->manual_stop = 1;
483 }
484 /* Master enable */
485 write_MASTER_CTL(iface, read_MASTER_CTL(iface) | MEN |
486 ((CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ>100) ? FAST : 0));
487 break;
488 case TWI_I2C_MODE_COMBINED:
489 write_XMT_DATA8(iface, iface->command);
490 write_INT_MASK(iface, MCOMP | MERR | RCVSERV | XMTSERV);
491 SSYNC();
492
493 if (iface->writeNum > 0)
494 write_MASTER_CTL(iface, (iface->writeNum + 1) << 6);
495 else
496 write_MASTER_CTL(iface, 0x1 << 6);
497 /* Master enable */
498 write_MASTER_CTL(iface, read_MASTER_CTL(iface) | MEN |
499 ((CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ>100) ? FAST : 0));
500 break;
501 default:
502 write_MASTER_CTL(iface, 0);
503 if (size != I2C_SMBUS_QUICK) {
504 /* Don't access xmit data register when this is a
505 * read operation.
506 */
507 if (iface->read_write != I2C_SMBUS_READ) {
508 if (iface->writeNum > 0) {
509 write_XMT_DATA8(iface,
510 *(iface->transPtr++));
511 if (iface->writeNum <= 255)
512 write_MASTER_CTL(iface,
513 iface->writeNum << 6);
514 else {
515 write_MASTER_CTL(iface,
516 0xff << 6);
517 iface->manual_stop = 1;
518 }
519 iface->writeNum--;
520 } else {
521 write_XMT_DATA8(iface, iface->command);
522 write_MASTER_CTL(iface, 1 << 6);
523 }
524 } else {
525 if (iface->readNum > 0 && iface->readNum <= 255)
526 write_MASTER_CTL(iface,
527 iface->readNum << 6);
528 else if (iface->readNum > 255) {
529 write_MASTER_CTL(iface, 0xff << 6);
530 iface->manual_stop = 1;
531 } else {
532 del_timer(&iface->timeout_timer);
533 break;
534 }
535 }
536 }
537 write_INT_MASK(iface, MCOMP | MERR |
538 ((iface->read_write == I2C_SMBUS_READ) ?
539 RCVSERV : XMTSERV));
540 SSYNC();
541
542 /* Master enable */
543 write_MASTER_CTL(iface, read_MASTER_CTL(iface) | MEN |
544 ((iface->read_write == I2C_SMBUS_READ) ? MDIR : 0) |
545 ((CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ > 100) ? FAST : 0));
546 break;
547 }
548 SSYNC();
549
550 wait_for_completion(&iface->complete);
551
552 rc = (iface->result >= 0) ? 0 : -1;
553
554 return rc;
555 }
556
557 /*
558 * Return what the adapter supports
559 */
560 static u32 bfin_twi_functionality(struct i2c_adapter *adap)
561 {
562 return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
563 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
564 I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_PROC_CALL |
565 I2C_FUNC_I2C;
566 }
567
568
569 static struct i2c_algorithm bfin_twi_algorithm = {
570 .master_xfer = bfin_twi_master_xfer,
571 .smbus_xfer = bfin_twi_smbus_xfer,
572 .functionality = bfin_twi_functionality,
573 };
574
575
576 static int i2c_bfin_twi_suspend(struct platform_device *dev, pm_message_t state)
577 {
578 struct bfin_twi_iface *iface = platform_get_drvdata(dev);
579
580 /* Disable TWI */
581 write_CONTROL(iface, read_CONTROL(iface) & ~TWI_ENA);
582 SSYNC();
583
584 return 0;
585 }
586
587 static int i2c_bfin_twi_resume(struct platform_device *dev)
588 {
589 struct bfin_twi_iface *iface = platform_get_drvdata(dev);
590
591 /* Enable TWI */
592 write_CONTROL(iface, read_CONTROL(iface) | TWI_ENA);
593 SSYNC();
594
595 return 0;
596 }
597
598 static int i2c_bfin_twi_probe(struct platform_device *pdev)
599 {
600 struct bfin_twi_iface *iface;
601 struct i2c_adapter *p_adap;
602 struct resource *res;
603 int rc;
604
605 iface = kzalloc(sizeof(struct bfin_twi_iface), GFP_KERNEL);
606 if (!iface) {
607 dev_err(&pdev->dev, "Cannot allocate memory\n");
608 rc = -ENOMEM;
609 goto out_error_nomem;
610 }
611
612 spin_lock_init(&(iface->lock));
613
614 /* Find and map our resources */
615 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
616 if (res == NULL) {
617 dev_err(&pdev->dev, "Cannot get IORESOURCE_MEM\n");
618 rc = -ENOENT;
619 goto out_error_get_res;
620 }
621
622 iface->regs_base = ioremap(res->start, res->end - res->start + 1);
623 if (iface->regs_base == NULL) {
624 dev_err(&pdev->dev, "Cannot map IO\n");
625 rc = -ENXIO;
626 goto out_error_ioremap;
627 }
628
629 iface->irq = platform_get_irq(pdev, 0);
630 if (iface->irq < 0) {
631 dev_err(&pdev->dev, "No IRQ specified\n");
632 rc = -ENOENT;
633 goto out_error_no_irq;
634 }
635
636 init_timer(&(iface->timeout_timer));
637 iface->timeout_timer.function = bfin_twi_timeout;
638 iface->timeout_timer.data = (unsigned long)iface;
639
640 p_adap = &iface->adap;
641 p_adap->id = I2C_HW_BLACKFIN;
642 p_adap->nr = pdev->id;
643 strlcpy(p_adap->name, pdev->name, sizeof(p_adap->name));
644 p_adap->algo = &bfin_twi_algorithm;
645 p_adap->algo_data = iface;
646 p_adap->class = I2C_CLASS_ALL;
647 p_adap->dev.parent = &pdev->dev;
648
649 rc = peripheral_request_list(pin_req[pdev->id], "i2c-bfin-twi");
650 if (rc) {
651 dev_err(&pdev->dev, "Can't setup pin mux!\n");
652 goto out_error_pin_mux;
653 }
654
655 rc = request_irq(iface->irq, bfin_twi_interrupt_entry,
656 IRQF_DISABLED, pdev->name, iface);
657 if (rc) {
658 dev_err(&pdev->dev, "Can't get IRQ %d !\n", iface->irq);
659 rc = -ENODEV;
660 goto out_error_req_irq;
661 }
662
663 /* Set TWI internal clock as 10MHz */
664 write_CONTROL(iface, ((get_sclk() / 1024 / 1024 + 5) / 10) & 0x7F);
665
666 /* Set Twi interface clock as specified */
667 write_CLKDIV(iface, ((5*1024 / CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ)
668 << 8) | ((5*1024 / CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ)
669 & 0xFF));
670
671 /* Enable TWI */
672 write_CONTROL(iface, read_CONTROL(iface) | TWI_ENA);
673 SSYNC();
674
675 rc = i2c_add_numbered_adapter(p_adap);
676 if (rc < 0) {
677 dev_err(&pdev->dev, "Can't add i2c adapter!\n");
678 goto out_error_add_adapter;
679 }
680
681 platform_set_drvdata(pdev, iface);
682
683 dev_info(&pdev->dev, "Blackfin BF5xx on-chip I2C TWI Contoller, "
684 "regs_base@%p\n", iface->regs_base);
685
686 return 0;
687
688 out_error_add_adapter:
689 free_irq(iface->irq, iface);
690 out_error_req_irq:
691 out_error_no_irq:
692 peripheral_free_list(pin_req[pdev->id]);
693 out_error_pin_mux:
694 iounmap(iface->regs_base);
695 out_error_ioremap:
696 out_error_get_res:
697 kfree(iface);
698 out_error_nomem:
699 return rc;
700 }
701
702 static int i2c_bfin_twi_remove(struct platform_device *pdev)
703 {
704 struct bfin_twi_iface *iface = platform_get_drvdata(pdev);
705
706 platform_set_drvdata(pdev, NULL);
707
708 i2c_del_adapter(&(iface->adap));
709 free_irq(iface->irq, iface);
710 peripheral_free_list(pin_req[pdev->id]);
711 iounmap(iface->regs_base);
712 kfree(iface);
713
714 return 0;
715 }
716
717 static struct platform_driver i2c_bfin_twi_driver = {
718 .probe = i2c_bfin_twi_probe,
719 .remove = i2c_bfin_twi_remove,
720 .suspend = i2c_bfin_twi_suspend,
721 .resume = i2c_bfin_twi_resume,
722 .driver = {
723 .name = "i2c-bfin-twi",
724 .owner = THIS_MODULE,
725 },
726 };
727
728 static int __init i2c_bfin_twi_init(void)
729 {
730 return platform_driver_register(&i2c_bfin_twi_driver);
731 }
732
733 static void __exit i2c_bfin_twi_exit(void)
734 {
735 platform_driver_unregister(&i2c_bfin_twi_driver);
736 }
737
738 module_init(i2c_bfin_twi_init);
739 module_exit(i2c_bfin_twi_exit);
740
741 MODULE_AUTHOR("Bryan Wu, Sonic Zhang");
742 MODULE_DESCRIPTION("Blackfin BF5xx on-chip I2C TWI Contoller Driver");
743 MODULE_LICENSE("GPL");
744 MODULE_ALIAS("platform:i2c-bfin-twi");
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