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PM / sleep: Asynchronous threads for suspend_noirq
[linux/fpc-iii.git] / drivers / spi / spi-sh.c
blobf6f2c701017795ed9a41133ac0da1151988c6f98
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 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
21 *
22 */
23
24 #include <linux/module.h>
25 #include <linux/kernel.h>
26 #include <linux/sched.h>
27 #include <linux/errno.h>
28 #include <linux/timer.h>
29 #include <linux/delay.h>
30 #include <linux/list.h>
31 #include <linux/workqueue.h>
32 #include <linux/interrupt.h>
33 #include <linux/platform_device.h>
34 #include <linux/io.h>
35 #include <linux/spi/spi.h>
36
37 #define SPI_SH_TBR 0x00
38 #define SPI_SH_RBR 0x00
39 #define SPI_SH_CR1 0x08
40 #define SPI_SH_CR2 0x10
41 #define SPI_SH_CR3 0x18
42 #define SPI_SH_CR4 0x20
43 #define SPI_SH_CR5 0x28
44
45 /* CR1 */
46 #define SPI_SH_TBE 0x80
47 #define SPI_SH_TBF 0x40
48 #define SPI_SH_RBE 0x20
49 #define SPI_SH_RBF 0x10
50 #define SPI_SH_PFONRD 0x08
51 #define SPI_SH_SSDB 0x04
52 #define SPI_SH_SSD 0x02
53 #define SPI_SH_SSA 0x01
54
55 /* CR2 */
56 #define SPI_SH_RSTF 0x80
57 #define SPI_SH_LOOPBK 0x40
58 #define SPI_SH_CPOL 0x20
59 #define SPI_SH_CPHA 0x10
60 #define SPI_SH_L1M0 0x08
61
62 /* CR3 */
63 #define SPI_SH_MAX_BYTE 0xFF
64
65 /* CR4 */
66 #define SPI_SH_TBEI 0x80
67 #define SPI_SH_TBFI 0x40
68 #define SPI_SH_RBEI 0x20
69 #define SPI_SH_RBFI 0x10
70 #define SPI_SH_WPABRT 0x04
71 #define SPI_SH_SSS 0x01
72
73 /* CR8 */
74 #define SPI_SH_P1L0 0x80
75 #define SPI_SH_PP1L0 0x40
76 #define SPI_SH_MUXI 0x20
77 #define SPI_SH_MUXIRQ 0x10
78
79 #define SPI_SH_FIFO_SIZE 32
80 #define SPI_SH_SEND_TIMEOUT (3 * HZ)
81 #define SPI_SH_RECEIVE_TIMEOUT (HZ >> 3)
82
83 #undef DEBUG
84
85 struct spi_sh_data {
86 void __iomem *addr;
87 int irq;
88 struct spi_master *master;
89 struct list_head queue;
90 struct workqueue_struct *workqueue;
91 struct work_struct ws;
92 unsigned long cr1;
93 wait_queue_head_t wait;
94 spinlock_t lock;
95 int width;
96 };
97
98 static void spi_sh_write(struct spi_sh_data *ss, unsigned long data,
99 unsigned long offset)
100 {
101 if (ss->width == 8)
102 iowrite8(data, ss->addr + (offset >> 2));
103 else if (ss->width == 32)
104 iowrite32(data, ss->addr + offset);
105 }
106
107 static unsigned long spi_sh_read(struct spi_sh_data *ss, unsigned long offset)
108 {
109 if (ss->width == 8)
110 return ioread8(ss->addr + (offset >> 2));
111 else if (ss->width == 32)
112 return ioread32(ss->addr + offset);
113 else
114 return 0;
115 }
116
117 static void spi_sh_set_bit(struct spi_sh_data *ss, unsigned long val,
118 unsigned long offset)
119 {
120 unsigned long tmp;
121
122 tmp = spi_sh_read(ss, offset);
123 tmp |= val;
124 spi_sh_write(ss, tmp, offset);
125 }
126
127 static void spi_sh_clear_bit(struct spi_sh_data *ss, unsigned long val,
128 unsigned long offset)
129 {
130 unsigned long tmp;
131
132 tmp = spi_sh_read(ss, offset);
133 tmp &= ~val;
134 spi_sh_write(ss, tmp, offset);
135 }
136
137 static void clear_fifo(struct spi_sh_data *ss)
138 {
139 spi_sh_set_bit(ss, SPI_SH_RSTF, SPI_SH_CR2);
140 spi_sh_clear_bit(ss, SPI_SH_RSTF, SPI_SH_CR2);
141 }
142
143 static int spi_sh_wait_receive_buffer(struct spi_sh_data *ss)
144 {
145 int timeout = 100000;
146
147 while (spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_RBE) {
148 udelay(10);
149 if (timeout-- < 0)
150 return -ETIMEDOUT;
151 }
152 return 0;
153 }
154
155 static int spi_sh_wait_write_buffer_empty(struct spi_sh_data *ss)
156 {
157 int timeout = 100000;
158
159 while (!(spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_TBE)) {
160 udelay(10);
161 if (timeout-- < 0)
162 return -ETIMEDOUT;
163 }
164 return 0;
165 }
166
167 static int spi_sh_send(struct spi_sh_data *ss, struct spi_message *mesg,
168 struct spi_transfer *t)
169 {
170 int i, retval = 0;
171 int remain = t->len;
172 int cur_len;
173 unsigned char *data;
174 long ret;
175
176 if (t->len)
177 spi_sh_set_bit(ss, SPI_SH_SSA, SPI_SH_CR1);
178
179 data = (unsigned char *)t->tx_buf;
180 while (remain > 0) {
181 cur_len = min(SPI_SH_FIFO_SIZE, remain);
182 for (i = 0; i < cur_len &&
183 !(spi_sh_read(ss, SPI_SH_CR4) &
184 SPI_SH_WPABRT) &&
185 !(spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_TBF);
186 i++)
187 spi_sh_write(ss, (unsigned long)data[i], SPI_SH_TBR);
188
189 if (spi_sh_read(ss, SPI_SH_CR4) & SPI_SH_WPABRT) {
190 /* Abort SPI operation */
191 spi_sh_set_bit(ss, SPI_SH_WPABRT, SPI_SH_CR4);
192 retval = -EIO;
193 break;
194 }
195
196 cur_len = i;
197
198 remain -= cur_len;
199 data += cur_len;
200
201 if (remain > 0) {
202 ss->cr1 &= ~SPI_SH_TBE;
203 spi_sh_set_bit(ss, SPI_SH_TBE, SPI_SH_CR4);
204 ret = wait_event_interruptible_timeout(ss->wait,
205 ss->cr1 & SPI_SH_TBE,
206 SPI_SH_SEND_TIMEOUT);
207 if (ret == 0 && !(ss->cr1 & SPI_SH_TBE)) {
208 printk(KERN_ERR "%s: timeout\n", __func__);
209 return -ETIMEDOUT;
210 }
211 }
212 }
213
214 if (list_is_last(&t->transfer_list, &mesg->transfers)) {
215 spi_sh_clear_bit(ss, SPI_SH_SSD | SPI_SH_SSDB, SPI_SH_CR1);
216 spi_sh_set_bit(ss, SPI_SH_SSA, SPI_SH_CR1);
217
218 ss->cr1 &= ~SPI_SH_TBE;
219 spi_sh_set_bit(ss, SPI_SH_TBE, SPI_SH_CR4);
220 ret = wait_event_interruptible_timeout(ss->wait,
221 ss->cr1 & SPI_SH_TBE,
222 SPI_SH_SEND_TIMEOUT);
223 if (ret == 0 && (ss->cr1 & SPI_SH_TBE)) {
224 printk(KERN_ERR "%s: timeout\n", __func__);
225 return -ETIMEDOUT;
226 }
227 }
228
229 return retval;
230 }
231
232 static int spi_sh_receive(struct spi_sh_data *ss, struct spi_message *mesg,
233 struct spi_transfer *t)
234 {
235 int i;
236 int remain = t->len;
237 int cur_len;
238 unsigned char *data;
239 long ret;
240
241 if (t->len > SPI_SH_MAX_BYTE)
242 spi_sh_write(ss, SPI_SH_MAX_BYTE, SPI_SH_CR3);
243 else
244 spi_sh_write(ss, t->len, SPI_SH_CR3);
245
246 spi_sh_clear_bit(ss, SPI_SH_SSD | SPI_SH_SSDB, SPI_SH_CR1);
247 spi_sh_set_bit(ss, SPI_SH_SSA, SPI_SH_CR1);
248
249 spi_sh_wait_write_buffer_empty(ss);
250
251 data = (unsigned char *)t->rx_buf;
252 while (remain > 0) {
253 if (remain >= SPI_SH_FIFO_SIZE) {
254 ss->cr1 &= ~SPI_SH_RBF;
255 spi_sh_set_bit(ss, SPI_SH_RBF, SPI_SH_CR4);
256 ret = wait_event_interruptible_timeout(ss->wait,
257 ss->cr1 & SPI_SH_RBF,
258 SPI_SH_RECEIVE_TIMEOUT);
259 if (ret == 0 &&
260 spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_RBE) {
261 printk(KERN_ERR "%s: timeout\n", __func__);
262 return -ETIMEDOUT;
263 }
264 }
265
266 cur_len = min(SPI_SH_FIFO_SIZE, remain);
267 for (i = 0; i < cur_len; i++) {
268 if (spi_sh_wait_receive_buffer(ss))
269 break;
270 data[i] = (unsigned char)spi_sh_read(ss, SPI_SH_RBR);
271 }
272
273 remain -= cur_len;
274 data += cur_len;
275 }
276
277 /* deassert CS when SPI is receiving. */
278 if (t->len > SPI_SH_MAX_BYTE) {
279 clear_fifo(ss);
280 spi_sh_write(ss, 1, SPI_SH_CR3);
281 } else {
282 spi_sh_write(ss, 0, SPI_SH_CR3);
283 }
284
285 return 0;
286 }
287
288 static void spi_sh_work(struct work_struct *work)
289 {
290 struct spi_sh_data *ss = container_of(work, struct spi_sh_data, ws);
291 struct spi_message *mesg;
292 struct spi_transfer *t;
293 unsigned long flags;
294 int ret;
295
296 pr_debug("%s: enter\n", __func__);
297
298 spin_lock_irqsave(&ss->lock, flags);
299 while (!list_empty(&ss->queue)) {
300 mesg = list_entry(ss->queue.next, struct spi_message, queue);
301 list_del_init(&mesg->queue);
302
303 spin_unlock_irqrestore(&ss->lock, flags);
304 list_for_each_entry(t, &mesg->transfers, transfer_list) {
305 pr_debug("tx_buf = %p, rx_buf = %p\n",
306 t->tx_buf, t->rx_buf);
307 pr_debug("len = %d, delay_usecs = %d\n",
308 t->len, t->delay_usecs);
309
310 if (t->tx_buf) {
311 ret = spi_sh_send(ss, mesg, t);
312 if (ret < 0)
313 goto error;
314 }
315 if (t->rx_buf) {
316 ret = spi_sh_receive(ss, mesg, t);
317 if (ret < 0)
318 goto error;
319 }
320 mesg->actual_length += t->len;
321 }
322 spin_lock_irqsave(&ss->lock, flags);
323
324 mesg->status = 0;
325 mesg->complete(mesg->context);
326 }
327
328 clear_fifo(ss);
329 spi_sh_set_bit(ss, SPI_SH_SSD, SPI_SH_CR1);
330 udelay(100);
331
332 spi_sh_clear_bit(ss, SPI_SH_SSA | SPI_SH_SSDB | SPI_SH_SSD,
333 SPI_SH_CR1);
334
335 clear_fifo(ss);
336
337 spin_unlock_irqrestore(&ss->lock, flags);
338
339 return;
340
341 error:
342 mesg->status = ret;
343 mesg->complete(mesg->context);
344
345 spi_sh_clear_bit(ss, SPI_SH_SSA | SPI_SH_SSDB | SPI_SH_SSD,
346 SPI_SH_CR1);
347 clear_fifo(ss);
348
349 }
350
351 static int spi_sh_setup(struct spi_device *spi)
352 {
353 struct spi_sh_data *ss = spi_master_get_devdata(spi->master);
354
355 pr_debug("%s: enter\n", __func__);
356
357 spi_sh_write(ss, 0xfe, SPI_SH_CR1); /* SPI sycle stop */
358 spi_sh_write(ss, 0x00, SPI_SH_CR1); /* CR1 init */
359 spi_sh_write(ss, 0x00, SPI_SH_CR3); /* CR3 init */
360
361 clear_fifo(ss);
362
363 /* 1/8 clock */
364 spi_sh_write(ss, spi_sh_read(ss, SPI_SH_CR2) | 0x07, SPI_SH_CR2);
365 udelay(10);
366
367 return 0;
368 }
369
370 static int spi_sh_transfer(struct spi_device *spi, struct spi_message *mesg)
371 {
372 struct spi_sh_data *ss = spi_master_get_devdata(spi->master);
373 unsigned long flags;
374
375 pr_debug("%s: enter\n", __func__);
376 pr_debug("\tmode = %02x\n", spi->mode);
377
378 spin_lock_irqsave(&ss->lock, flags);
379
380 mesg->actual_length = 0;
381 mesg->status = -EINPROGRESS;
382
383 spi_sh_clear_bit(ss, SPI_SH_SSA, SPI_SH_CR1);
384
385 list_add_tail(&mesg->queue, &ss->queue);
386 queue_work(ss->workqueue, &ss->ws);
387
388 spin_unlock_irqrestore(&ss->lock, flags);
389
390 return 0;
391 }
392
393 static void spi_sh_cleanup(struct spi_device *spi)
394 {
395 struct spi_sh_data *ss = spi_master_get_devdata(spi->master);
396
397 pr_debug("%s: enter\n", __func__);
398
399 spi_sh_clear_bit(ss, SPI_SH_SSA | SPI_SH_SSDB | SPI_SH_SSD,
400 SPI_SH_CR1);
401 }
402
403 static irqreturn_t spi_sh_irq(int irq, void *_ss)
404 {
405 struct spi_sh_data *ss = (struct spi_sh_data *)_ss;
406 unsigned long cr1;
407
408 cr1 = spi_sh_read(ss, SPI_SH_CR1);
409 if (cr1 & SPI_SH_TBE)
410 ss->cr1 |= SPI_SH_TBE;
411 if (cr1 & SPI_SH_TBF)
412 ss->cr1 |= SPI_SH_TBF;
413 if (cr1 & SPI_SH_RBE)
414 ss->cr1 |= SPI_SH_RBE;
415 if (cr1 & SPI_SH_RBF)
416 ss->cr1 |= SPI_SH_RBF;
417
418 if (ss->cr1) {
419 spi_sh_clear_bit(ss, ss->cr1, SPI_SH_CR4);
420 wake_up(&ss->wait);
421 }
422
423 return IRQ_HANDLED;
424 }
425
426 static int spi_sh_remove(struct platform_device *pdev)
427 {
428 struct spi_sh_data *ss = platform_get_drvdata(pdev);
429
430 spi_unregister_master(ss->master);
431 destroy_workqueue(ss->workqueue);
432 free_irq(ss->irq, ss);
433 iounmap(ss->addr);
434
435 return 0;
436 }
437
438 static int spi_sh_probe(struct platform_device *pdev)
439 {
440 struct resource *res;
441 struct spi_master *master;
442 struct spi_sh_data *ss;
443 int ret, irq;
444
445 /* get base addr */
446 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
447 if (unlikely(res == NULL)) {
448 dev_err(&pdev->dev, "invalid resource\n");
449 return -EINVAL;
450 }
451
452 irq = platform_get_irq(pdev, 0);
453 if (irq < 0) {
454 dev_err(&pdev->dev, "platform_get_irq error\n");
455 return -ENODEV;
456 }
457
458 master = spi_alloc_master(&pdev->dev, sizeof(struct spi_sh_data));
459 if (master == NULL) {
460 dev_err(&pdev->dev, "spi_alloc_master error.\n");
461 return -ENOMEM;
462 }
463
464 ss = spi_master_get_devdata(master);
465 platform_set_drvdata(pdev, ss);
466
467 switch (res->flags & IORESOURCE_MEM_TYPE_MASK) {
468 case IORESOURCE_MEM_8BIT:
469 ss->width = 8;
470 break;
471 case IORESOURCE_MEM_32BIT:
472 ss->width = 32;
473 break;
474 default:
475 dev_err(&pdev->dev, "No support width\n");
476 ret = -ENODEV;
477 goto error1;
478 }
479 ss->irq = irq;
480 ss->master = master;
481 ss->addr = ioremap(res->start, resource_size(res));
482 if (ss->addr == NULL) {
483 dev_err(&pdev->dev, "ioremap error.\n");
484 ret = -ENOMEM;
485 goto error1;
486 }
487 INIT_LIST_HEAD(&ss->queue);
488 spin_lock_init(&ss->lock);
489 INIT_WORK(&ss->ws, spi_sh_work);
490 init_waitqueue_head(&ss->wait);
491 ss->workqueue = create_singlethread_workqueue(
492 dev_name(master->dev.parent));
493 if (ss->workqueue == NULL) {
494 dev_err(&pdev->dev, "create workqueue error\n");
495 ret = -EBUSY;
496 goto error2;
497 }
498
499 ret = request_irq(irq, spi_sh_irq, 0, "spi_sh", ss);
500 if (ret < 0) {
501 dev_err(&pdev->dev, "request_irq error\n");
502 goto error3;
503 }
504
505 master->num_chipselect = 2;
506 master->bus_num = pdev->id;
507 master->setup = spi_sh_setup;
508 master->transfer = spi_sh_transfer;
509 master->cleanup = spi_sh_cleanup;
510
511 ret = spi_register_master(master);
512 if (ret < 0) {
513 printk(KERN_ERR "spi_register_master error.\n");
514 goto error4;
515 }
516
517 return 0;
518
519 error4:
520 free_irq(irq, ss);
521 error3:
522 destroy_workqueue(ss->workqueue);
523 error2:
524 iounmap(ss->addr);
525 error1:
526 spi_master_put(master);
527
528 return ret;
529 }
530
531 static struct platform_driver spi_sh_driver = {
532 .probe = spi_sh_probe,
533 .remove = spi_sh_remove,
534 .driver = {
535 .name = "sh_spi",
536 .owner = THIS_MODULE,
537 },
538 };
539 module_platform_driver(spi_sh_driver);
540
541 MODULE_DESCRIPTION("SH SPI bus driver");
542 MODULE_LICENSE("GPL");
543 MODULE_AUTHOR("Yoshihiro Shimoda");
544 MODULE_ALIAS("platform:sh_spi");
Linux with added FPC-III support