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ededad3e WZ |
1 | /* |
2 | * linux/drivers/i2c/busses/i2c-nuc900.c | |
3 | * | |
4 | * Copyright (c) 2010 Nuvoton technology corporation. | |
5 | * | |
6 | * This driver based on S3C2410 I2C driver of Ben Dooks <ben-Y5A6D6n0/KfQXOPxS62xeg@public.gmane.org>. | |
7 | * Written by Wan ZongShun <mcuos.com-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> | |
8 | * | |
9 | * This program is free software; you can redistribute it and/or modify | |
10 | * it under the terms of the GNU General Public License as published by | |
11 | * the Free Software Foundation;version 2 of the License. | |
12 | * | |
13 | */ | |
14 | ||
15 | #include <linux/kernel.h> | |
16 | #include <linux/module.h> | |
17 | ||
18 | #include <linux/i2c.h> | |
ededad3e WZ |
19 | #include <linux/init.h> |
20 | #include <linux/time.h> | |
21 | #include <linux/interrupt.h> | |
22 | #include <linux/delay.h> | |
23 | #include <linux/errno.h> | |
24 | #include <linux/err.h> | |
25 | #include <linux/platform_device.h> | |
26 | #include <linux/clk.h> | |
27 | #include <linux/cpufreq.h> | |
28 | #include <linux/slab.h> | |
29 | #include <linux/io.h> | |
30 | ||
31 | #include <mach/mfp.h> | |
32 | #include <mach/i2c.h> | |
33 | ||
34 | /* nuc900 i2c registers offset */ | |
35 | ||
36 | #define CSR 0x00 | |
37 | #define DIVIDER 0x04 | |
38 | #define CMDR 0x08 | |
39 | #define SWR 0x0C | |
40 | #define RXR 0x10 | |
41 | #define TXR 0x14 | |
42 | ||
43 | /* nuc900 i2c CSR register bits */ | |
44 | ||
45 | #define IRQEN 0x003 | |
46 | #define I2CBUSY 0x400 | |
47 | #define I2CSTART 0x018 | |
48 | #define IRQFLAG 0x004 | |
49 | #define ARBIT_LOST 0x200 | |
50 | #define SLAVE_ACK 0x800 | |
51 | ||
52 | /* nuc900 i2c CMDR register bits */ | |
53 | ||
54 | #define I2C_CMD_START 0x10 | |
55 | #define I2C_CMD_STOP 0x08 | |
56 | #define I2C_CMD_READ 0x04 | |
57 | #define I2C_CMD_WRITE 0x02 | |
58 | #define I2C_CMD_NACK 0x01 | |
59 | ||
60 | /* i2c controller state */ | |
61 | ||
62 | enum nuc900_i2c_state { | |
63 | STATE_IDLE, | |
64 | STATE_START, | |
65 | STATE_READ, | |
66 | STATE_WRITE, | |
67 | STATE_STOP | |
68 | }; | |
69 | ||
70 | /* i2c controller private data */ | |
71 | ||
72 | struct nuc900_i2c { | |
73 | spinlock_t lock; | |
74 | wait_queue_head_t wait; | |
75 | ||
76 | struct i2c_msg *msg; | |
77 | unsigned int msg_num; | |
78 | unsigned int msg_idx; | |
79 | unsigned int msg_ptr; | |
80 | unsigned int irq; | |
81 | ||
82 | enum nuc900_i2c_state state; | |
83 | ||
84 | void __iomem *regs; | |
85 | struct clk *clk; | |
86 | struct device *dev; | |
87 | struct resource *ioarea; | |
88 | struct i2c_adapter adap; | |
89 | }; | |
90 | ||
91 | /* nuc900_i2c_master_complete | |
92 | * | |
93 | * complete the message and wake up the caller, using the given return code, | |
94 | * or zero to mean ok. | |
95 | */ | |
96 | ||
97 | static inline void nuc900_i2c_master_complete(struct nuc900_i2c *i2c, int ret) | |
98 | { | |
99 | dev_dbg(i2c->dev, "master_complete %d\n", ret); | |
100 | ||
101 | i2c->msg_ptr = 0; | |
102 | i2c->msg = NULL; | |
103 | i2c->msg_idx++; | |
104 | i2c->msg_num = 0; | |
105 | if (ret) | |
106 | i2c->msg_idx = ret; | |
107 | ||
108 | wake_up(&i2c->wait); | |
109 | } | |
110 | ||
111 | /* irq enable/disable functions */ | |
112 | ||
113 | static inline void nuc900_i2c_disable_irq(struct nuc900_i2c *i2c) | |
114 | { | |
115 | unsigned long tmp; | |
116 | ||
117 | tmp = readl(i2c->regs + CSR); | |
118 | writel(tmp & ~IRQEN, i2c->regs + CSR); | |
119 | } | |
120 | ||
121 | static inline void nuc900_i2c_enable_irq(struct nuc900_i2c *i2c) | |
122 | { | |
123 | unsigned long tmp; | |
124 | ||
125 | tmp = readl(i2c->regs + CSR); | |
126 | writel(tmp | IRQEN, i2c->regs + CSR); | |
127 | } | |
128 | ||
129 | ||
130 | /* nuc900_i2c_message_start | |
131 | * | |
132 | * put the start of a message onto the bus | |
133 | */ | |
134 | ||
135 | static void nuc900_i2c_message_start(struct nuc900_i2c *i2c, | |
136 | struct i2c_msg *msg) | |
137 | { | |
138 | unsigned int addr = (msg->addr & 0x7f) << 1; | |
139 | ||
140 | if (msg->flags & I2C_M_RD) | |
141 | addr |= 0x1; | |
142 | writel(addr & 0xff, i2c->regs + TXR); | |
143 | writel(I2C_CMD_START | I2C_CMD_WRITE, i2c->regs + CMDR); | |
144 | } | |
145 | ||
146 | static inline void nuc900_i2c_stop(struct nuc900_i2c *i2c, int ret) | |
147 | { | |
148 | ||
149 | dev_dbg(i2c->dev, "STOP\n"); | |
150 | ||
151 | /* stop the transfer */ | |
152 | i2c->state = STATE_STOP; | |
153 | writel(I2C_CMD_STOP, i2c->regs + CMDR); | |
154 | ||
155 | nuc900_i2c_master_complete(i2c, ret); | |
156 | nuc900_i2c_disable_irq(i2c); | |
157 | } | |
158 | ||
159 | /* helper functions to determine the current state in the set of | |
160 | * messages we are sending | |
161 | */ | |
162 | ||
163 | /* is_lastmsg() | |
164 | * | |
165 | * returns TRUE if the current message is the last in the set | |
166 | */ | |
167 | ||
168 | static inline int is_lastmsg(struct nuc900_i2c *i2c) | |
169 | { | |
170 | return i2c->msg_idx >= (i2c->msg_num - 1); | |
171 | } | |
172 | ||
173 | /* is_msglast | |
174 | * | |
175 | * returns TRUE if we this is the last byte in the current message | |
176 | */ | |
177 | ||
178 | static inline int is_msglast(struct nuc900_i2c *i2c) | |
179 | { | |
180 | return i2c->msg_ptr == i2c->msg->len-1; | |
181 | } | |
182 | ||
183 | /* is_msgend | |
184 | * | |
185 | * returns TRUE if we reached the end of the current message | |
186 | */ | |
187 | ||
188 | static inline int is_msgend(struct nuc900_i2c *i2c) | |
189 | { | |
190 | return i2c->msg_ptr >= i2c->msg->len; | |
191 | } | |
192 | ||
193 | /* i2c_nuc900_irq_nextbyte | |
194 | * | |
195 | * process an interrupt and work out what to do | |
196 | */ | |
197 | ||
198 | static void i2c_nuc900_irq_nextbyte(struct nuc900_i2c *i2c, | |
199 | unsigned long iicstat) | |
200 | { | |
201 | unsigned char byte; | |
202 | ||
203 | switch (i2c->state) { | |
204 | ||
205 | case STATE_IDLE: | |
206 | dev_err(i2c->dev, "%s: called in STATE_IDLE\n", __func__); | |
207 | break; | |
208 | ||
209 | case STATE_STOP: | |
210 | dev_err(i2c->dev, "%s: called in STATE_STOP\n", __func__); | |
211 | nuc900_i2c_disable_irq(i2c); | |
212 | break; | |
213 | ||
214 | case STATE_START: | |
215 | /* last thing we did was send a start condition on the | |
216 | * bus, or started a new i2c message | |
217 | */ | |
218 | ||
219 | if (iicstat & SLAVE_ACK && | |
220 | !(i2c->msg->flags & I2C_M_IGNORE_NAK)) { | |
221 | /* ack was not received... */ | |
222 | ||
223 | dev_dbg(i2c->dev, "ack was not received\n"); | |
224 | nuc900_i2c_stop(i2c, -ENXIO); | |
225 | break; | |
226 | } | |
227 | ||
228 | if (i2c->msg->flags & I2C_M_RD) | |
229 | i2c->state = STATE_READ; | |
230 | else | |
231 | i2c->state = STATE_WRITE; | |
232 | ||
233 | /* terminate the transfer if there is nothing to do | |
234 | * as this is used by the i2c probe to find devices. | |
235 | */ | |
236 | ||
237 | if (is_lastmsg(i2c) && i2c->msg->len == 0) { | |
238 | nuc900_i2c_stop(i2c, 0); | |
239 | break; | |
240 | } | |
241 | ||
242 | if (i2c->state == STATE_READ) | |
243 | goto prepare_read; | |
244 | ||
245 | /* fall through to the write state, as we will need to | |
246 | * send a byte as well | |
247 | */ | |
248 | ||
249 | case STATE_WRITE: | |
250 | /* we are writing data to the device... check for the | |
251 | * end of the message, and if so, work out what to do | |
252 | */ | |
253 | ||
254 | if (!(i2c->msg->flags & I2C_M_IGNORE_NAK)) { | |
255 | if (iicstat & SLAVE_ACK) { | |
256 | dev_dbg(i2c->dev, "WRITE: No Ack\n"); | |
257 | ||
258 | nuc900_i2c_stop(i2c, -ECONNREFUSED); | |
259 | break; | |
260 | } | |
261 | } | |
262 | ||
263 | retry_write: | |
264 | ||
265 | if (!is_msgend(i2c)) { | |
266 | byte = i2c->msg->buf[i2c->msg_ptr++]; | |
267 | writeb(byte, i2c->regs + TXR); | |
268 | writel(I2C_CMD_WRITE, i2c->regs + CMDR); | |
269 | ||
270 | } else if (!is_lastmsg(i2c)) { | |
271 | /* we need to go to the next i2c message */ | |
272 | ||
273 | dev_dbg(i2c->dev, "WRITE: Next Message\n"); | |
274 | ||
275 | i2c->msg_ptr = 0; | |
276 | i2c->msg_idx++; | |
277 | i2c->msg++; | |
278 | ||
279 | /* check to see if we need to do another message */ | |
280 | if (i2c->msg->flags & I2C_M_NOSTART) { | |
281 | ||
282 | if (i2c->msg->flags & I2C_M_RD) { | |
283 | /* cannot do this, the controller | |
284 | * forces us to send a new START | |
285 | * when we change direction | |
286 | */ | |
287 | ||
288 | nuc900_i2c_stop(i2c, -EINVAL); | |
289 | } | |
290 | ||
291 | goto retry_write; | |
292 | } else { | |
293 | /* send the new start */ | |
294 | nuc900_i2c_message_start(i2c, i2c->msg); | |
295 | i2c->state = STATE_START; | |
296 | } | |
297 | ||
298 | } else { | |
299 | /* send stop */ | |
300 | ||
301 | nuc900_i2c_stop(i2c, 0); | |
302 | } | |
303 | break; | |
304 | ||
305 | case STATE_READ: | |
306 | /* we have a byte of data in the data register, do | |
307 | * something with it, and then work out wether we are | |
308 | * going to do any more read/write | |
309 | */ | |
310 | ||
311 | byte = readb(i2c->regs + RXR); | |
312 | i2c->msg->buf[i2c->msg_ptr++] = byte; | |
313 | ||
314 | prepare_read: | |
315 | if (is_msglast(i2c)) { | |
316 | /* last byte of buffer */ | |
317 | ||
318 | if (is_lastmsg(i2c)) | |
319 | writel(I2C_CMD_READ | I2C_CMD_NACK, | |
320 | i2c->regs + CMDR); | |
321 | ||
322 | } else if (is_msgend(i2c)) { | |
323 | /* ok, we've read the entire buffer, see if there | |
324 | * is anything else we need to do | |
325 | */ | |
326 | ||
327 | if (is_lastmsg(i2c)) { | |
328 | /* last message, send stop and complete */ | |
329 | dev_dbg(i2c->dev, "READ: Send Stop\n"); | |
330 | ||
331 | nuc900_i2c_stop(i2c, 0); | |
332 | } else { | |
333 | /* go to the next transfer */ | |
334 | dev_dbg(i2c->dev, "READ: Next Transfer\n"); | |
335 | ||
336 | i2c->msg_ptr = 0; | |
337 | i2c->msg_idx++; | |
338 | i2c->msg++; | |
339 | ||
340 | writel(I2C_CMD_READ, i2c->regs + CMDR); | |
341 | } | |
342 | ||
343 | } else { | |
344 | writel(I2C_CMD_READ, i2c->regs + CMDR); | |
345 | } | |
346 | ||
347 | break; | |
348 | } | |
349 | } | |
350 | ||
351 | /* nuc900_i2c_irq | |
352 | * | |
353 | * top level IRQ servicing routine | |
354 | */ | |
355 | ||
356 | static irqreturn_t nuc900_i2c_irq(int irqno, void *dev_id) | |
357 | { | |
358 | struct nuc900_i2c *i2c = dev_id; | |
359 | unsigned long status; | |
360 | ||
361 | status = readl(i2c->regs + CSR); | |
362 | writel(status | IRQFLAG, i2c->regs + CSR); | |
363 | ||
364 | if (status & ARBIT_LOST) { | |
365 | /* deal with arbitration loss */ | |
366 | dev_err(i2c->dev, "deal with arbitration loss\n"); | |
367 | goto out; | |
368 | } | |
369 | ||
370 | if (i2c->state == STATE_IDLE) { | |
371 | dev_dbg(i2c->dev, "IRQ: error i2c->state == IDLE\n"); | |
372 | goto out; | |
373 | } | |
374 | ||
375 | /* pretty much this leaves us with the fact that we've | |
376 | * transmitted or received whatever byte we last sent | |
377 | */ | |
378 | ||
379 | i2c_nuc900_irq_nextbyte(i2c, status); | |
380 | ||
381 | out: | |
382 | return IRQ_HANDLED; | |
383 | } | |
384 | ||
385 | ||
386 | /* nuc900_i2c_set_master | |
387 | * | |
388 | * get the i2c bus for a master transaction | |
389 | */ | |
390 | ||
391 | static int nuc900_i2c_set_master(struct nuc900_i2c *i2c) | |
392 | { | |
393 | int timeout = 400; | |
394 | ||
395 | while (timeout-- > 0) { | |
396 | if (((readl(i2c->regs + SWR) & I2CSTART) == I2CSTART) && | |
397 | ((readl(i2c->regs + CSR) & I2CBUSY) == 0)) { | |
398 | return 0; | |
399 | } | |
400 | ||
401 | msleep(1); | |
402 | } | |
403 | ||
404 | return -ETIMEDOUT; | |
405 | } | |
406 | ||
407 | /* nuc900_i2c_doxfer | |
408 | * | |
409 | * this starts an i2c transfer | |
410 | */ | |
411 | ||
412 | static int nuc900_i2c_doxfer(struct nuc900_i2c *i2c, | |
413 | struct i2c_msg *msgs, int num) | |
414 | { | |
415 | unsigned long iicstat, timeout; | |
416 | int spins = 20; | |
417 | int ret; | |
418 | ||
419 | ret = nuc900_i2c_set_master(i2c); | |
420 | if (ret != 0) { | |
421 | dev_err(i2c->dev, "cannot get bus (error %d)\n", ret); | |
422 | ret = -EAGAIN; | |
423 | goto out; | |
424 | } | |
425 | ||
426 | spin_lock_irq(&i2c->lock); | |
427 | ||
428 | i2c->msg = msgs; | |
429 | i2c->msg_num = num; | |
430 | i2c->msg_ptr = 0; | |
431 | i2c->msg_idx = 0; | |
432 | i2c->state = STATE_START; | |
433 | ||
434 | nuc900_i2c_message_start(i2c, msgs); | |
435 | spin_unlock_irq(&i2c->lock); | |
436 | ||
437 | timeout = wait_event_timeout(i2c->wait, i2c->msg_num == 0, HZ * 5); | |
438 | ||
439 | ret = i2c->msg_idx; | |
440 | ||
441 | /* having these next two as dev_err() makes life very | |
442 | * noisy when doing an i2cdetect | |
443 | */ | |
444 | ||
445 | if (timeout == 0) | |
446 | dev_dbg(i2c->dev, "timeout\n"); | |
447 | else if (ret != num) | |
448 | dev_dbg(i2c->dev, "incomplete xfer (%d)\n", ret); | |
449 | ||
450 | /* ensure the stop has been through the bus */ | |
451 | ||
452 | dev_dbg(i2c->dev, "waiting for bus idle\n"); | |
453 | ||
454 | /* first, try busy waiting briefly */ | |
455 | do { | |
456 | iicstat = readl(i2c->regs + CSR); | |
457 | } while ((iicstat & I2CBUSY) && --spins); | |
458 | ||
459 | /* if that timed out sleep */ | |
460 | if (!spins) { | |
461 | msleep(1); | |
462 | iicstat = readl(i2c->regs + CSR); | |
463 | } | |
464 | ||
465 | if (iicstat & I2CBUSY) | |
466 | dev_warn(i2c->dev, "timeout waiting for bus idle\n"); | |
467 | ||
468 | out: | |
469 | return ret; | |
470 | } | |
471 | ||
472 | /* nuc900_i2c_xfer | |
473 | * | |
474 | * first port of call from the i2c bus code when an message needs | |
475 | * transferring across the i2c bus. | |
476 | */ | |
477 | ||
478 | static int nuc900_i2c_xfer(struct i2c_adapter *adap, | |
479 | struct i2c_msg *msgs, int num) | |
480 | { | |
481 | struct nuc900_i2c *i2c = (struct nuc900_i2c *)adap->algo_data; | |
482 | int retry; | |
483 | int ret; | |
484 | ||
485 | nuc900_i2c_enable_irq(i2c); | |
486 | ||
487 | for (retry = 0; retry < adap->retries; retry++) { | |
488 | ||
489 | ret = nuc900_i2c_doxfer(i2c, msgs, num); | |
490 | ||
491 | if (ret != -EAGAIN) | |
492 | return ret; | |
493 | ||
494 | dev_dbg(i2c->dev, "Retrying transmission (%d)\n", retry); | |
495 | ||
496 | udelay(100); | |
497 | } | |
498 | ||
499 | return -EREMOTEIO; | |
500 | } | |
501 | ||
502 | /* declare our i2c functionality */ | |
503 | static u32 nuc900_i2c_func(struct i2c_adapter *adap) | |
504 | { | |
14674e70 MB |
505 | return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_NOSTART | |
506 | I2C_FUNC_PROTOCOL_MANGLING; | |
ededad3e WZ |
507 | } |
508 | ||
509 | /* i2c bus registration info */ | |
510 | ||
511 | static const struct i2c_algorithm nuc900_i2c_algorithm = { | |
512 | .master_xfer = nuc900_i2c_xfer, | |
513 | .functionality = nuc900_i2c_func, | |
514 | }; | |
515 | ||
516 | /* nuc900_i2c_probe | |
517 | * | |
518 | * called by the bus driver when a suitable device is found | |
519 | */ | |
520 | ||
521 | static int __devinit nuc900_i2c_probe(struct platform_device *pdev) | |
522 | { | |
523 | struct nuc900_i2c *i2c; | |
524 | struct nuc900_platform_i2c *pdata; | |
525 | struct resource *res; | |
526 | int ret; | |
527 | ||
528 | pdata = pdev->dev.platform_data; | |
529 | if (!pdata) { | |
530 | dev_err(&pdev->dev, "no platform data\n"); | |
531 | return -EINVAL; | |
532 | } | |
533 | ||
534 | i2c = kzalloc(sizeof(struct nuc900_i2c), GFP_KERNEL); | |
535 | if (!i2c) { | |
536 | dev_err(&pdev->dev, "no memory for state\n"); | |
537 | return -ENOMEM; | |
538 | } | |
539 | ||
540 | strlcpy(i2c->adap.name, "nuc900-i2c0", sizeof(i2c->adap.name)); | |
541 | i2c->adap.owner = THIS_MODULE; | |
542 | i2c->adap.algo = &nuc900_i2c_algorithm; | |
543 | i2c->adap.retries = 2; | |
544 | i2c->adap.class = I2C_CLASS_HWMON | I2C_CLASS_SPD; | |
545 | ||
546 | spin_lock_init(&i2c->lock); | |
547 | init_waitqueue_head(&i2c->wait); | |
548 | ||
549 | /* find the clock and enable it */ | |
550 | ||
551 | i2c->dev = &pdev->dev; | |
552 | i2c->clk = clk_get(&pdev->dev, NULL); | |
553 | if (IS_ERR(i2c->clk)) { | |
554 | dev_err(&pdev->dev, "cannot get clock\n"); | |
555 | ret = -ENOENT; | |
556 | goto err_noclk; | |
557 | } | |
558 | ||
559 | dev_dbg(&pdev->dev, "clock source %p\n", i2c->clk); | |
560 | ||
561 | clk_enable(i2c->clk); | |
562 | ||
563 | /* map the registers */ | |
564 | ||
565 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); | |
566 | if (res == NULL) { | |
567 | dev_err(&pdev->dev, "cannot find IO resource\n"); | |
568 | ret = -ENOENT; | |
569 | goto err_clk; | |
570 | } | |
571 | ||
572 | i2c->ioarea = request_mem_region(res->start, resource_size(res), | |
573 | pdev->name); | |
574 | ||
575 | if (i2c->ioarea == NULL) { | |
576 | dev_err(&pdev->dev, "cannot request IO\n"); | |
577 | ret = -ENXIO; | |
578 | goto err_clk; | |
579 | } | |
580 | ||
581 | i2c->regs = ioremap(res->start, resource_size(res)); | |
582 | ||
583 | if (i2c->regs == NULL) { | |
584 | dev_err(&pdev->dev, "cannot map IO\n"); | |
585 | ret = -ENXIO; | |
586 | goto err_ioarea; | |
587 | } | |
588 | ||
589 | dev_dbg(&pdev->dev, "registers %p (%p, %p)\n", | |
590 | i2c->regs, i2c->ioarea, res); | |
591 | ||
592 | /* setup info block for the i2c core */ | |
593 | ||
594 | i2c->adap.algo_data = i2c; | |
595 | i2c->adap.dev.parent = &pdev->dev; | |
596 | ||
97371fa9 | 597 | mfp_set_groupg(&pdev->dev, NULL); |
ededad3e WZ |
598 | |
599 | clk_get_rate(i2c->clk); | |
600 | ||
601 | ret = (i2c->clk.apbfreq)/(pdata->bus_freq * 5) - 1; | |
602 | writel(ret & 0xffff, i2c->regs + DIVIDER); | |
603 | ||
604 | /* find the IRQ for this unit (note, this relies on the init call to | |
605 | * ensure no current IRQs pending | |
606 | */ | |
607 | ||
608 | i2c->irq = ret = platform_get_irq(pdev, 0); | |
609 | if (ret <= 0) { | |
610 | dev_err(&pdev->dev, "cannot find IRQ\n"); | |
611 | goto err_iomap; | |
612 | } | |
613 | ||
4311051c | 614 | ret = request_irq(i2c->irq, nuc900_i2c_irq, IRQF_SHARED, |
ededad3e WZ |
615 | dev_name(&pdev->dev), i2c); |
616 | ||
617 | if (ret != 0) { | |
618 | dev_err(&pdev->dev, "cannot claim IRQ %d\n", i2c->irq); | |
619 | goto err_iomap; | |
620 | } | |
621 | ||
622 | /* Note, previous versions of the driver used i2c_add_adapter() | |
623 | * to add the bus at any number. We now pass the bus number via | |
624 | * the platform data, so if unset it will now default to always | |
625 | * being bus 0. | |
626 | */ | |
627 | ||
628 | i2c->adap.nr = pdata->bus_num; | |
629 | ||
630 | ret = i2c_add_numbered_adapter(&i2c->adap); | |
631 | if (ret < 0) { | |
632 | dev_err(&pdev->dev, "failed to add bus to i2c core\n"); | |
633 | goto err_irq; | |
634 | } | |
635 | ||
636 | platform_set_drvdata(pdev, i2c); | |
637 | ||
638 | dev_info(&pdev->dev, "%s: NUC900 I2C adapter\n", | |
639 | dev_name(&i2c->adap.dev)); | |
640 | return 0; | |
641 | ||
642 | err_irq: | |
643 | free_irq(i2c->irq, i2c); | |
644 | ||
645 | err_iomap: | |
646 | iounmap(i2c->regs); | |
647 | ||
648 | err_ioarea: | |
649 | release_resource(i2c->ioarea); | |
650 | kfree(i2c->ioarea); | |
651 | ||
652 | err_clk: | |
653 | clk_disable(i2c->clk); | |
654 | clk_put(i2c->clk); | |
655 | ||
656 | err_noclk: | |
657 | kfree(i2c); | |
658 | return ret; | |
659 | } | |
660 | ||
661 | /* nuc900_i2c_remove | |
662 | * | |
663 | * called when device is removed from the bus | |
664 | */ | |
665 | ||
666 | static int __devexit nuc900_i2c_remove(struct platform_device *pdev) | |
667 | { | |
668 | struct nuc900_i2c *i2c = platform_get_drvdata(pdev); | |
669 | ||
670 | i2c_del_adapter(&i2c->adap); | |
671 | free_irq(i2c->irq, i2c); | |
672 | ||
673 | clk_disable(i2c->clk); | |
674 | clk_put(i2c->clk); | |
675 | ||
676 | iounmap(i2c->regs); | |
677 | ||
678 | release_resource(i2c->ioarea); | |
679 | kfree(i2c->ioarea); | |
680 | kfree(i2c); | |
681 | ||
682 | return 0; | |
683 | } | |
684 | ||
685 | static struct platform_driver nuc900_i2c_driver = { | |
686 | .probe = nuc900_i2c_probe, | |
687 | .remove = __devexit_p(nuc900_i2c_remove), | |
688 | .driver = { | |
689 | .owner = THIS_MODULE, | |
690 | .name = "nuc900-i2c0", | |
691 | }, | |
692 | }; | |
693 | ||
694 | static int __init i2c_adap_nuc900_init(void) | |
695 | { | |
696 | return platform_driver_register(&nuc900_i2c_driver); | |
697 | } | |
698 | ||
699 | static void __exit i2c_adap_nuc900_exit(void) | |
700 | { | |
701 | platform_driver_unregister(&nuc900_i2c_driver); | |
702 | } | |
703 | subsys_initcall(i2c_adap_nuc900_init); | |
704 | module_exit(i2c_adap_nuc900_exit); | |
705 | ||
706 | MODULE_DESCRIPTION("NUC900 I2C Bus driver"); | |
707 | MODULE_AUTHOR("Wan ZongShun, <mcuos.com-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>"); | |
708 | MODULE_LICENSE("GPL"); | |
709 | MODULE_ALIAS("platform:nuc900-i2c0"); |