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hwmon: (adt7475) fan stall prevention
[linux/fpc-iii.git] / drivers / spi / spi-sh.c
blob2bf53f0e27d9e0fe7bb179c2d3a143c012010a55
1 /*
2 * SH SPI bus driver
3 *
4 * Copyright (C) 2011 Renesas Solutions Corp.
5 *
6 * Based on pxa2xx_spi.c:
7 * Copyright (C) 2005 Stephen Street / StreetFire Sound Labs
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 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 */
18
19 #include <linux/module.h>
20 #include <linux/kernel.h>
21 #include <linux/sched.h>
22 #include <linux/errno.h>
23 #include <linux/timer.h>
24 #include <linux/delay.h>
25 #include <linux/list.h>
26 #include <linux/workqueue.h>
27 #include <linux/interrupt.h>
28 #include <linux/platform_device.h>
29 #include <linux/io.h>
30 #include <linux/spi/spi.h>
31
32 #define SPI_SH_TBR 0x00
33 #define SPI_SH_RBR 0x00
34 #define SPI_SH_CR1 0x08
35 #define SPI_SH_CR2 0x10
36 #define SPI_SH_CR3 0x18
37 #define SPI_SH_CR4 0x20
38 #define SPI_SH_CR5 0x28
39
40 /* CR1 */
41 #define SPI_SH_TBE 0x80
42 #define SPI_SH_TBF 0x40
43 #define SPI_SH_RBE 0x20
44 #define SPI_SH_RBF 0x10
45 #define SPI_SH_PFONRD 0x08
46 #define SPI_SH_SSDB 0x04
47 #define SPI_SH_SSD 0x02
48 #define SPI_SH_SSA 0x01
49
50 /* CR2 */
51 #define SPI_SH_RSTF 0x80
52 #define SPI_SH_LOOPBK 0x40
53 #define SPI_SH_CPOL 0x20
54 #define SPI_SH_CPHA 0x10
55 #define SPI_SH_L1M0 0x08
56
57 /* CR3 */
58 #define SPI_SH_MAX_BYTE 0xFF
59
60 /* CR4 */
61 #define SPI_SH_TBEI 0x80
62 #define SPI_SH_TBFI 0x40
63 #define SPI_SH_RBEI 0x20
64 #define SPI_SH_RBFI 0x10
65 #define SPI_SH_WPABRT 0x04
66 #define SPI_SH_SSS 0x01
67
68 /* CR8 */
69 #define SPI_SH_P1L0 0x80
70 #define SPI_SH_PP1L0 0x40
71 #define SPI_SH_MUXI 0x20
72 #define SPI_SH_MUXIRQ 0x10
73
74 #define SPI_SH_FIFO_SIZE 32
75 #define SPI_SH_SEND_TIMEOUT (3 * HZ)
76 #define SPI_SH_RECEIVE_TIMEOUT (HZ >> 3)
77
78 #undef DEBUG
79
80 struct spi_sh_data {
81 void __iomem *addr;
82 int irq;
83 struct spi_master *master;
84 struct list_head queue;
85 struct work_struct ws;
86 unsigned long cr1;
87 wait_queue_head_t wait;
88 spinlock_t lock;
89 int width;
90 };
91
92 static void spi_sh_write(struct spi_sh_data *ss, unsigned long data,
93 unsigned long offset)
94 {
95 if (ss->width == 8)
96 iowrite8(data, ss->addr + (offset >> 2));
97 else if (ss->width == 32)
98 iowrite32(data, ss->addr + offset);
99 }
100
101 static unsigned long spi_sh_read(struct spi_sh_data *ss, unsigned long offset)
102 {
103 if (ss->width == 8)
104 return ioread8(ss->addr + (offset >> 2));
105 else if (ss->width == 32)
106 return ioread32(ss->addr + offset);
107 else
108 return 0;
109 }
110
111 static void spi_sh_set_bit(struct spi_sh_data *ss, unsigned long val,
112 unsigned long offset)
113 {
114 unsigned long tmp;
115
116 tmp = spi_sh_read(ss, offset);
117 tmp |= val;
118 spi_sh_write(ss, tmp, offset);
119 }
120
121 static void spi_sh_clear_bit(struct spi_sh_data *ss, unsigned long val,
122 unsigned long offset)
123 {
124 unsigned long tmp;
125
126 tmp = spi_sh_read(ss, offset);
127 tmp &= ~val;
128 spi_sh_write(ss, tmp, offset);
129 }
130
131 static void clear_fifo(struct spi_sh_data *ss)
132 {
133 spi_sh_set_bit(ss, SPI_SH_RSTF, SPI_SH_CR2);
134 spi_sh_clear_bit(ss, SPI_SH_RSTF, SPI_SH_CR2);
135 }
136
137 static int spi_sh_wait_receive_buffer(struct spi_sh_data *ss)
138 {
139 int timeout = 100000;
140
141 while (spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_RBE) {
142 udelay(10);
143 if (timeout-- < 0)
144 return -ETIMEDOUT;
145 }
146 return 0;
147 }
148
149 static int spi_sh_wait_write_buffer_empty(struct spi_sh_data *ss)
150 {
151 int timeout = 100000;
152
153 while (!(spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_TBE)) {
154 udelay(10);
155 if (timeout-- < 0)
156 return -ETIMEDOUT;
157 }
158 return 0;
159 }
160
161 static int spi_sh_send(struct spi_sh_data *ss, struct spi_message *mesg,
162 struct spi_transfer *t)
163 {
164 int i, retval = 0;
165 int remain = t->len;
166 int cur_len;
167 unsigned char *data;
168 long ret;
169
170 if (t->len)
171 spi_sh_set_bit(ss, SPI_SH_SSA, SPI_SH_CR1);
172
173 data = (unsigned char *)t->tx_buf;
174 while (remain > 0) {
175 cur_len = min(SPI_SH_FIFO_SIZE, remain);
176 for (i = 0; i < cur_len &&
177 !(spi_sh_read(ss, SPI_SH_CR4) &
178 SPI_SH_WPABRT) &&
179 !(spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_TBF);
180 i++)
181 spi_sh_write(ss, (unsigned long)data[i], SPI_SH_TBR);
182
183 if (spi_sh_read(ss, SPI_SH_CR4) & SPI_SH_WPABRT) {
184 /* Abort SPI operation */
185 spi_sh_set_bit(ss, SPI_SH_WPABRT, SPI_SH_CR4);
186 retval = -EIO;
187 break;
188 }
189
190 cur_len = i;
191
192 remain -= cur_len;
193 data += cur_len;
194
195 if (remain > 0) {
196 ss->cr1 &= ~SPI_SH_TBE;
197 spi_sh_set_bit(ss, SPI_SH_TBE, SPI_SH_CR4);
198 ret = wait_event_interruptible_timeout(ss->wait,
199 ss->cr1 & SPI_SH_TBE,
200 SPI_SH_SEND_TIMEOUT);
201 if (ret == 0 && !(ss->cr1 & SPI_SH_TBE)) {
202 printk(KERN_ERR "%s: timeout\n", __func__);
203 return -ETIMEDOUT;
204 }
205 }
206 }
207
208 if (list_is_last(&t->transfer_list, &mesg->transfers)) {
209 spi_sh_clear_bit(ss, SPI_SH_SSD | SPI_SH_SSDB, SPI_SH_CR1);
210 spi_sh_set_bit(ss, SPI_SH_SSA, SPI_SH_CR1);
211
212 ss->cr1 &= ~SPI_SH_TBE;
213 spi_sh_set_bit(ss, SPI_SH_TBE, SPI_SH_CR4);
214 ret = wait_event_interruptible_timeout(ss->wait,
215 ss->cr1 & SPI_SH_TBE,
216 SPI_SH_SEND_TIMEOUT);
217 if (ret == 0 && (ss->cr1 & SPI_SH_TBE)) {
218 printk(KERN_ERR "%s: timeout\n", __func__);
219 return -ETIMEDOUT;
220 }
221 }
222
223 return retval;
224 }
225
226 static int spi_sh_receive(struct spi_sh_data *ss, struct spi_message *mesg,
227 struct spi_transfer *t)
228 {
229 int i;
230 int remain = t->len;
231 int cur_len;
232 unsigned char *data;
233 long ret;
234
235 if (t->len > SPI_SH_MAX_BYTE)
236 spi_sh_write(ss, SPI_SH_MAX_BYTE, SPI_SH_CR3);
237 else
238 spi_sh_write(ss, t->len, SPI_SH_CR3);
239
240 spi_sh_clear_bit(ss, SPI_SH_SSD | SPI_SH_SSDB, SPI_SH_CR1);
241 spi_sh_set_bit(ss, SPI_SH_SSA, SPI_SH_CR1);
242
243 spi_sh_wait_write_buffer_empty(ss);
244
245 data = (unsigned char *)t->rx_buf;
246 while (remain > 0) {
247 if (remain >= SPI_SH_FIFO_SIZE) {
248 ss->cr1 &= ~SPI_SH_RBF;
249 spi_sh_set_bit(ss, SPI_SH_RBF, SPI_SH_CR4);
250 ret = wait_event_interruptible_timeout(ss->wait,
251 ss->cr1 & SPI_SH_RBF,
252 SPI_SH_RECEIVE_TIMEOUT);
253 if (ret == 0 &&
254 spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_RBE) {
255 printk(KERN_ERR "%s: timeout\n", __func__);
256 return -ETIMEDOUT;
257 }
258 }
259
260 cur_len = min(SPI_SH_FIFO_SIZE, remain);
261 for (i = 0; i < cur_len; i++) {
262 if (spi_sh_wait_receive_buffer(ss))
263 break;
264 data[i] = (unsigned char)spi_sh_read(ss, SPI_SH_RBR);
265 }
266
267 remain -= cur_len;
268 data += cur_len;
269 }
270
271 /* deassert CS when SPI is receiving. */
272 if (t->len > SPI_SH_MAX_BYTE) {
273 clear_fifo(ss);
274 spi_sh_write(ss, 1, SPI_SH_CR3);
275 } else {
276 spi_sh_write(ss, 0, SPI_SH_CR3);
277 }
278
279 return 0;
280 }
281
282 static void spi_sh_work(struct work_struct *work)
283 {
284 struct spi_sh_data *ss = container_of(work, struct spi_sh_data, ws);
285 struct spi_message *mesg;
286 struct spi_transfer *t;
287 unsigned long flags;
288 int ret;
289
290 pr_debug("%s: enter\n", __func__);
291
292 spin_lock_irqsave(&ss->lock, flags);
293 while (!list_empty(&ss->queue)) {
294 mesg = list_entry(ss->queue.next, struct spi_message, queue);
295 list_del_init(&mesg->queue);
296
297 spin_unlock_irqrestore(&ss->lock, flags);
298 list_for_each_entry(t, &mesg->transfers, transfer_list) {
299 pr_debug("tx_buf = %p, rx_buf = %p\n",
300 t->tx_buf, t->rx_buf);
301 pr_debug("len = %d, delay_usecs = %d\n",
302 t->len, t->delay_usecs);
303
304 if (t->tx_buf) {
305 ret = spi_sh_send(ss, mesg, t);
306 if (ret < 0)
307 goto error;
308 }
309 if (t->rx_buf) {
310 ret = spi_sh_receive(ss, mesg, t);
311 if (ret < 0)
312 goto error;
313 }
314 mesg->actual_length += t->len;
315 }
316 spin_lock_irqsave(&ss->lock, flags);
317
318 mesg->status = 0;
319 if (mesg->complete)
320 mesg->complete(mesg->context);
321 }
322
323 clear_fifo(ss);
324 spi_sh_set_bit(ss, SPI_SH_SSD, SPI_SH_CR1);
325 udelay(100);
326
327 spi_sh_clear_bit(ss, SPI_SH_SSA | SPI_SH_SSDB | SPI_SH_SSD,
328 SPI_SH_CR1);
329
330 clear_fifo(ss);
331
332 spin_unlock_irqrestore(&ss->lock, flags);
333
334 return;
335
336 error:
337 mesg->status = ret;
338 if (mesg->complete)
339 mesg->complete(mesg->context);
340
341 spi_sh_clear_bit(ss, SPI_SH_SSA | SPI_SH_SSDB | SPI_SH_SSD,
342 SPI_SH_CR1);
343 clear_fifo(ss);
344
345 }
346
347 static int spi_sh_setup(struct spi_device *spi)
348 {
349 struct spi_sh_data *ss = spi_master_get_devdata(spi->master);
350
351 pr_debug("%s: enter\n", __func__);
352
353 spi_sh_write(ss, 0xfe, SPI_SH_CR1); /* SPI sycle stop */
354 spi_sh_write(ss, 0x00, SPI_SH_CR1); /* CR1 init */
355 spi_sh_write(ss, 0x00, SPI_SH_CR3); /* CR3 init */
356
357 clear_fifo(ss);
358
359 /* 1/8 clock */
360 spi_sh_write(ss, spi_sh_read(ss, SPI_SH_CR2) | 0x07, SPI_SH_CR2);
361 udelay(10);
362
363 return 0;
364 }
365
366 static int spi_sh_transfer(struct spi_device *spi, struct spi_message *mesg)
367 {
368 struct spi_sh_data *ss = spi_master_get_devdata(spi->master);
369 unsigned long flags;
370
371 pr_debug("%s: enter\n", __func__);
372 pr_debug("\tmode = %02x\n", spi->mode);
373
374 spin_lock_irqsave(&ss->lock, flags);
375
376 mesg->actual_length = 0;
377 mesg->status = -EINPROGRESS;
378
379 spi_sh_clear_bit(ss, SPI_SH_SSA, SPI_SH_CR1);
380
381 list_add_tail(&mesg->queue, &ss->queue);
382 schedule_work(&ss->ws);
383
384 spin_unlock_irqrestore(&ss->lock, flags);
385
386 return 0;
387 }
388
389 static void spi_sh_cleanup(struct spi_device *spi)
390 {
391 struct spi_sh_data *ss = spi_master_get_devdata(spi->master);
392
393 pr_debug("%s: enter\n", __func__);
394
395 spi_sh_clear_bit(ss, SPI_SH_SSA | SPI_SH_SSDB | SPI_SH_SSD,
396 SPI_SH_CR1);
397 }
398
399 static irqreturn_t spi_sh_irq(int irq, void *_ss)
400 {
401 struct spi_sh_data *ss = (struct spi_sh_data *)_ss;
402 unsigned long cr1;
403
404 cr1 = spi_sh_read(ss, SPI_SH_CR1);
405 if (cr1 & SPI_SH_TBE)
406 ss->cr1 |= SPI_SH_TBE;
407 if (cr1 & SPI_SH_TBF)
408 ss->cr1 |= SPI_SH_TBF;
409 if (cr1 & SPI_SH_RBE)
410 ss->cr1 |= SPI_SH_RBE;
411 if (cr1 & SPI_SH_RBF)
412 ss->cr1 |= SPI_SH_RBF;
413
414 if (ss->cr1) {
415 spi_sh_clear_bit(ss, ss->cr1, SPI_SH_CR4);
416 wake_up(&ss->wait);
417 }
418
419 return IRQ_HANDLED;
420 }
421
422 static int spi_sh_remove(struct platform_device *pdev)
423 {
424 struct spi_sh_data *ss = platform_get_drvdata(pdev);
425
426 spi_unregister_master(ss->master);
427 flush_work(&ss->ws);
428 free_irq(ss->irq, ss);
429
430 return 0;
431 }
432
433 static int spi_sh_probe(struct platform_device *pdev)
434 {
435 struct resource *res;
436 struct spi_master *master;
437 struct spi_sh_data *ss;
438 int ret, irq;
439
440 /* get base addr */
441 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
442 if (unlikely(res == NULL)) {
443 dev_err(&pdev->dev, "invalid resource\n");
444 return -EINVAL;
445 }
446
447 irq = platform_get_irq(pdev, 0);
448 if (irq < 0) {
449 dev_err(&pdev->dev, "platform_get_irq error\n");
450 return -ENODEV;
451 }
452
453 master = spi_alloc_master(&pdev->dev, sizeof(struct spi_sh_data));
454 if (master == NULL) {
455 dev_err(&pdev->dev, "spi_alloc_master error.\n");
456 return -ENOMEM;
457 }
458
459 ss = spi_master_get_devdata(master);
460 platform_set_drvdata(pdev, ss);
461
462 switch (res->flags & IORESOURCE_MEM_TYPE_MASK) {
463 case IORESOURCE_MEM_8BIT:
464 ss->width = 8;
465 break;
466 case IORESOURCE_MEM_32BIT:
467 ss->width = 32;
468 break;
469 default:
470 dev_err(&pdev->dev, "No support width\n");
471 ret = -ENODEV;
472 goto error1;
473 }
474 ss->irq = irq;
475 ss->master = master;
476 ss->addr = devm_ioremap(&pdev->dev, res->start, resource_size(res));
477 if (ss->addr == NULL) {
478 dev_err(&pdev->dev, "ioremap error.\n");
479 ret = -ENOMEM;
480 goto error1;
481 }
482 INIT_LIST_HEAD(&ss->queue);
483 spin_lock_init(&ss->lock);
484 INIT_WORK(&ss->ws, spi_sh_work);
485 init_waitqueue_head(&ss->wait);
486
487 ret = request_irq(irq, spi_sh_irq, 0, "spi_sh", ss);
488 if (ret < 0) {
489 dev_err(&pdev->dev, "request_irq error\n");
490 goto error1;
491 }
492
493 master->num_chipselect = 2;
494 master->bus_num = pdev->id;
495 master->setup = spi_sh_setup;
496 master->transfer = spi_sh_transfer;
497 master->cleanup = spi_sh_cleanup;
498
499 ret = spi_register_master(master);
500 if (ret < 0) {
501 printk(KERN_ERR "spi_register_master error.\n");
502 goto error3;
503 }
504
505 return 0;
506
507 error3:
508 free_irq(irq, ss);
509 error1:
510 spi_master_put(master);
511
512 return ret;
513 }
514
515 static struct platform_driver spi_sh_driver = {
516 .probe = spi_sh_probe,
517 .remove = spi_sh_remove,
518 .driver = {
519 .name = "sh_spi",
520 },
521 };
522 module_platform_driver(spi_sh_driver);
523
524 MODULE_DESCRIPTION("SH SPI bus driver");
525 MODULE_LICENSE("GPL");
526 MODULE_AUTHOR("Yoshihiro Shimoda");
527 MODULE_ALIAS("platform:sh_spi");
Linux with added FPC-III support