diff options
Diffstat (limited to 'arch/arm/plat-omap/mailbox.c')
-rw-r--r-- | arch/arm/plat-omap/mailbox.c | 509 |
1 files changed, 509 insertions, 0 deletions
diff --git a/arch/arm/plat-omap/mailbox.c b/arch/arm/plat-omap/mailbox.c new file mode 100644 index 000000000000..de7e6ef48bd0 --- /dev/null +++ b/arch/arm/plat-omap/mailbox.c | |||
@@ -0,0 +1,509 @@ | |||
1 | /* | ||
2 | * OMAP mailbox driver | ||
3 | * | ||
4 | * Copyright (C) 2006 Nokia Corporation. All rights reserved. | ||
5 | * | ||
6 | * Contact: Toshihiro Kobayashi <toshihiro.kobayashi@nokia.com> | ||
7 | * Restructured by Hiroshi DOYU <Hiroshi.DOYU@nokia.com> | ||
8 | * | ||
9 | * This program is free software; you can redistribute it and/or | ||
10 | * modify it under the terms of the GNU General Public License | ||
11 | * version 2 as published by the Free Software Foundation. | ||
12 | * | ||
13 | * This program is distributed in the hope that it will be useful, but | ||
14 | * WITHOUT ANY WARRANTY; without even the implied warranty of | ||
15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | ||
16 | * 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 | ||
21 | * 02110-1301 USA | ||
22 | * | ||
23 | */ | ||
24 | |||
25 | #include <linux/init.h> | ||
26 | #include <linux/module.h> | ||
27 | #include <linux/sched.h> | ||
28 | #include <linux/interrupt.h> | ||
29 | #include <linux/device.h> | ||
30 | #include <linux/blkdev.h> | ||
31 | #include <linux/err.h> | ||
32 | #include <linux/delay.h> | ||
33 | #include <asm/io.h> | ||
34 | #include <asm/arch/mailbox.h> | ||
35 | #include "mailbox.h" | ||
36 | |||
37 | static struct omap_mbox *mboxes; | ||
38 | static DEFINE_RWLOCK(mboxes_lock); | ||
39 | |||
40 | /* Mailbox Sequence Bit function */ | ||
41 | void omap_mbox_init_seq(struct omap_mbox *mbox) | ||
42 | { | ||
43 | mbox_seq_init(mbox); | ||
44 | } | ||
45 | EXPORT_SYMBOL(omap_mbox_init_seq); | ||
46 | |||
47 | /* | ||
48 | * message sender | ||
49 | */ | ||
50 | static int __mbox_msg_send(struct omap_mbox *mbox, mbox_msg_t msg, void *arg) | ||
51 | { | ||
52 | int ret = 0, i = 1000; | ||
53 | |||
54 | while (mbox_fifo_full(mbox)) { | ||
55 | if (mbox->ops->type == OMAP_MBOX_TYPE2) | ||
56 | return -1; | ||
57 | if (--i == 0) | ||
58 | return -1; | ||
59 | udelay(1); | ||
60 | } | ||
61 | |||
62 | if (arg && mbox->txq->callback) { | ||
63 | ret = mbox->txq->callback(arg); | ||
64 | if (ret) | ||
65 | goto out; | ||
66 | } | ||
67 | |||
68 | mbox_seq_toggle(mbox, &msg); | ||
69 | mbox_fifo_write(mbox, msg); | ||
70 | out: | ||
71 | return ret; | ||
72 | } | ||
73 | |||
74 | int omap_mbox_msg_send(struct omap_mbox *mbox, mbox_msg_t msg, void* arg) | ||
75 | { | ||
76 | struct request *rq; | ||
77 | struct request_queue *q = mbox->txq->queue; | ||
78 | int ret = 0; | ||
79 | |||
80 | rq = blk_get_request(q, WRITE, GFP_ATOMIC); | ||
81 | if (unlikely(!rq)) { | ||
82 | ret = -ENOMEM; | ||
83 | goto fail; | ||
84 | } | ||
85 | |||
86 | rq->data = (void *)msg; | ||
87 | blk_insert_request(q, rq, 0, arg); | ||
88 | |||
89 | schedule_work(&mbox->txq->work); | ||
90 | fail: | ||
91 | return ret; | ||
92 | } | ||
93 | EXPORT_SYMBOL(omap_mbox_msg_send); | ||
94 | |||
95 | static void mbox_tx_work(struct work_struct *work) | ||
96 | { | ||
97 | int ret; | ||
98 | struct request *rq; | ||
99 | struct omap_mbox_queue *mq = container_of(work, | ||
100 | struct omap_mbox_queue, work); | ||
101 | struct omap_mbox *mbox = mq->queue->queuedata; | ||
102 | struct request_queue *q = mbox->txq->queue; | ||
103 | |||
104 | while (1) { | ||
105 | spin_lock(q->queue_lock); | ||
106 | rq = elv_next_request(q); | ||
107 | spin_unlock(q->queue_lock); | ||
108 | |||
109 | if (!rq) | ||
110 | break; | ||
111 | |||
112 | ret = __mbox_msg_send(mbox, (mbox_msg_t) rq->data, rq->special); | ||
113 | if (ret) { | ||
114 | enable_mbox_irq(mbox, IRQ_TX); | ||
115 | return; | ||
116 | } | ||
117 | |||
118 | spin_lock(q->queue_lock); | ||
119 | blkdev_dequeue_request(rq); | ||
120 | end_that_request_last(rq, 0); | ||
121 | spin_unlock(q->queue_lock); | ||
122 | } | ||
123 | } | ||
124 | |||
125 | /* | ||
126 | * Message receiver(workqueue) | ||
127 | */ | ||
128 | static void mbox_rx_work(struct work_struct *work) | ||
129 | { | ||
130 | struct omap_mbox_queue *mq = | ||
131 | container_of(work, struct omap_mbox_queue, work); | ||
132 | struct omap_mbox *mbox = mq->queue->queuedata; | ||
133 | struct request_queue *q = mbox->rxq->queue; | ||
134 | struct request *rq; | ||
135 | mbox_msg_t msg; | ||
136 | unsigned long flags; | ||
137 | |||
138 | if (mbox->rxq->callback == NULL) { | ||
139 | sysfs_notify(&mbox->dev.kobj, NULL, "mbox"); | ||
140 | return; | ||
141 | } | ||
142 | |||
143 | while (1) { | ||
144 | spin_lock_irqsave(q->queue_lock, flags); | ||
145 | rq = elv_next_request(q); | ||
146 | spin_unlock_irqrestore(q->queue_lock, flags); | ||
147 | if (!rq) | ||
148 | break; | ||
149 | |||
150 | msg = (mbox_msg_t) rq->data; | ||
151 | |||
152 | spin_lock_irqsave(q->queue_lock, flags); | ||
153 | blkdev_dequeue_request(rq); | ||
154 | end_that_request_last(rq, 0); | ||
155 | spin_unlock_irqrestore(q->queue_lock, flags); | ||
156 | |||
157 | mbox->rxq->callback((void *)msg); | ||
158 | } | ||
159 | } | ||
160 | |||
161 | /* | ||
162 | * Mailbox interrupt handler | ||
163 | */ | ||
164 | static void mbox_txq_fn(request_queue_t * q) | ||
165 | { | ||
166 | } | ||
167 | |||
168 | static void mbox_rxq_fn(request_queue_t * q) | ||
169 | { | ||
170 | } | ||
171 | |||
172 | static void __mbox_tx_interrupt(struct omap_mbox *mbox) | ||
173 | { | ||
174 | disable_mbox_irq(mbox, IRQ_TX); | ||
175 | ack_mbox_irq(mbox, IRQ_TX); | ||
176 | schedule_work(&mbox->txq->work); | ||
177 | } | ||
178 | |||
179 | static void __mbox_rx_interrupt(struct omap_mbox *mbox) | ||
180 | { | ||
181 | struct request *rq; | ||
182 | mbox_msg_t msg; | ||
183 | request_queue_t *q = mbox->rxq->queue; | ||
184 | |||
185 | disable_mbox_irq(mbox, IRQ_RX); | ||
186 | |||
187 | while (!mbox_fifo_empty(mbox)) { | ||
188 | rq = blk_get_request(q, WRITE, GFP_ATOMIC); | ||
189 | if (unlikely(!rq)) | ||
190 | goto nomem; | ||
191 | |||
192 | msg = mbox_fifo_read(mbox); | ||
193 | rq->data = (void *)msg; | ||
194 | |||
195 | if (unlikely(mbox_seq_test(mbox, msg))) { | ||
196 | pr_info("mbox: Illegal seq bit!(%08x)\n", msg); | ||
197 | if (mbox->err_notify) | ||
198 | mbox->err_notify(); | ||
199 | } | ||
200 | |||
201 | blk_insert_request(q, rq, 0, NULL); | ||
202 | if (mbox->ops->type == OMAP_MBOX_TYPE1) | ||
203 | break; | ||
204 | } | ||
205 | |||
206 | /* no more messages in the fifo. clear IRQ source. */ | ||
207 | ack_mbox_irq(mbox, IRQ_RX); | ||
208 | enable_mbox_irq(mbox, IRQ_RX); | ||
209 | nomem: | ||
210 | schedule_work(&mbox->rxq->work); | ||
211 | } | ||
212 | |||
213 | static irqreturn_t mbox_interrupt(int irq, void *p) | ||
214 | { | ||
215 | struct omap_mbox *mbox = (struct omap_mbox *)p; | ||
216 | |||
217 | if (is_mbox_irq(mbox, IRQ_TX)) | ||
218 | __mbox_tx_interrupt(mbox); | ||
219 | |||
220 | if (is_mbox_irq(mbox, IRQ_RX)) | ||
221 | __mbox_rx_interrupt(mbox); | ||
222 | |||
223 | return IRQ_HANDLED; | ||
224 | } | ||
225 | |||
226 | /* | ||
227 | * sysfs files | ||
228 | */ | ||
229 | static ssize_t | ||
230 | omap_mbox_write(struct device *dev, struct device_attribute *attr, | ||
231 | const char * buf, size_t count) | ||
232 | { | ||
233 | int ret; | ||
234 | mbox_msg_t *p = (mbox_msg_t *)buf; | ||
235 | struct omap_mbox *mbox = dev_get_drvdata(dev); | ||
236 | |||
237 | for (; count >= sizeof(mbox_msg_t); count -= sizeof(mbox_msg_t)) { | ||
238 | ret = omap_mbox_msg_send(mbox, be32_to_cpu(*p), NULL); | ||
239 | if (ret) | ||
240 | return -EAGAIN; | ||
241 | p++; | ||
242 | } | ||
243 | |||
244 | return (size_t)((char *)p - buf); | ||
245 | } | ||
246 | |||
247 | static ssize_t | ||
248 | omap_mbox_read(struct device *dev, struct device_attribute *attr, char *buf) | ||
249 | { | ||
250 | unsigned long flags; | ||
251 | struct request *rq; | ||
252 | mbox_msg_t *p = (mbox_msg_t *) buf; | ||
253 | struct omap_mbox *mbox = dev_get_drvdata(dev); | ||
254 | struct request_queue *q = mbox->rxq->queue; | ||
255 | |||
256 | while (1) { | ||
257 | spin_lock_irqsave(q->queue_lock, flags); | ||
258 | rq = elv_next_request(q); | ||
259 | spin_unlock_irqrestore(q->queue_lock, flags); | ||
260 | |||
261 | if (!rq) | ||
262 | break; | ||
263 | |||
264 | *p = (mbox_msg_t) rq->data; | ||
265 | |||
266 | spin_lock_irqsave(q->queue_lock, flags); | ||
267 | blkdev_dequeue_request(rq); | ||
268 | end_that_request_last(rq, 0); | ||
269 | spin_unlock_irqrestore(q->queue_lock, flags); | ||
270 | |||
271 | if (unlikely(mbox_seq_test(mbox, *p))) { | ||
272 | pr_info("mbox: Illegal seq bit!(%08x) ignored\n", *p); | ||
273 | continue; | ||
274 | } | ||
275 | p++; | ||
276 | } | ||
277 | |||
278 | pr_debug("%02x %02x %02x %02x\n", buf[0], buf[1], buf[2], buf[3]); | ||
279 | |||
280 | return (size_t) ((char *)p - buf); | ||
281 | } | ||
282 | |||
283 | static DEVICE_ATTR(mbox, S_IRUGO | S_IWUSR, omap_mbox_read, omap_mbox_write); | ||
284 | |||
285 | static ssize_t mbox_show(struct class *class, char *buf) | ||
286 | { | ||
287 | return sprintf(buf, "mbox"); | ||
288 | } | ||
289 | |||
290 | static CLASS_ATTR(mbox, S_IRUGO, mbox_show, NULL); | ||
291 | |||
292 | static struct class omap_mbox_class = { | ||
293 | .name = "omap_mbox", | ||
294 | }; | ||
295 | |||
296 | static struct omap_mbox_queue *mbox_queue_alloc(struct omap_mbox *mbox, | ||
297 | request_fn_proc * proc, | ||
298 | void (*work) (struct work_struct *)) | ||
299 | { | ||
300 | request_queue_t *q; | ||
301 | struct omap_mbox_queue *mq; | ||
302 | |||
303 | mq = kzalloc(sizeof(struct omap_mbox_queue), GFP_KERNEL); | ||
304 | if (!mq) | ||
305 | return NULL; | ||
306 | |||
307 | spin_lock_init(&mq->lock); | ||
308 | |||
309 | q = blk_init_queue(proc, &mq->lock); | ||
310 | if (!q) | ||
311 | goto error; | ||
312 | q->queuedata = mbox; | ||
313 | mq->queue = q; | ||
314 | |||
315 | INIT_WORK(&mq->work, work); | ||
316 | |||
317 | return mq; | ||
318 | error: | ||
319 | kfree(mq); | ||
320 | return NULL; | ||
321 | } | ||
322 | |||
323 | static void mbox_queue_free(struct omap_mbox_queue *q) | ||
324 | { | ||
325 | blk_cleanup_queue(q->queue); | ||
326 | kfree(q); | ||
327 | } | ||
328 | |||
329 | static int omap_mbox_init(struct omap_mbox *mbox) | ||
330 | { | ||
331 | int ret; | ||
332 | struct omap_mbox_queue *mq; | ||
333 | |||
334 | if (likely(mbox->ops->startup)) { | ||
335 | ret = mbox->ops->startup(mbox); | ||
336 | if (unlikely(ret)) | ||
337 | return ret; | ||
338 | } | ||
339 | |||
340 | mbox->dev.class = &omap_mbox_class; | ||
341 | strlcpy(mbox->dev.bus_id, mbox->name, KOBJ_NAME_LEN); | ||
342 | dev_set_drvdata(&mbox->dev, mbox); | ||
343 | |||
344 | ret = device_register(&mbox->dev); | ||
345 | if (unlikely(ret)) | ||
346 | goto fail_device_reg; | ||
347 | |||
348 | ret = device_create_file(&mbox->dev, &dev_attr_mbox); | ||
349 | if (unlikely(ret)) { | ||
350 | printk(KERN_ERR | ||
351 | "device_create_file failed: %d\n", ret); | ||
352 | goto fail_create_mbox; | ||
353 | } | ||
354 | |||
355 | ret = request_irq(mbox->irq, mbox_interrupt, IRQF_DISABLED, | ||
356 | mbox->name, mbox); | ||
357 | if (unlikely(ret)) { | ||
358 | printk(KERN_ERR | ||
359 | "failed to register mailbox interrupt:%d\n", ret); | ||
360 | goto fail_request_irq; | ||
361 | } | ||
362 | enable_mbox_irq(mbox, IRQ_RX); | ||
363 | |||
364 | mq = mbox_queue_alloc(mbox, mbox_txq_fn, mbox_tx_work); | ||
365 | if (!mq) { | ||
366 | ret = -ENOMEM; | ||
367 | goto fail_alloc_txq; | ||
368 | } | ||
369 | mbox->txq = mq; | ||
370 | |||
371 | mq = mbox_queue_alloc(mbox, mbox_rxq_fn, mbox_rx_work); | ||
372 | if (!mq) { | ||
373 | ret = -ENOMEM; | ||
374 | goto fail_alloc_rxq; | ||
375 | } | ||
376 | mbox->rxq = mq; | ||
377 | |||
378 | return 0; | ||
379 | |||
380 | fail_alloc_rxq: | ||
381 | mbox_queue_free(mbox->txq); | ||
382 | fail_alloc_txq: | ||
383 | free_irq(mbox->irq, mbox); | ||
384 | fail_request_irq: | ||
385 | device_remove_file(&mbox->dev, &dev_attr_mbox); | ||
386 | fail_create_mbox: | ||
387 | device_unregister(&mbox->dev); | ||
388 | fail_device_reg: | ||
389 | if (unlikely(mbox->ops->shutdown)) | ||
390 | mbox->ops->shutdown(mbox); | ||
391 | |||
392 | return ret; | ||
393 | } | ||
394 | |||
395 | static void omap_mbox_fini(struct omap_mbox *mbox) | ||
396 | { | ||
397 | mbox_queue_free(mbox->txq); | ||
398 | mbox_queue_free(mbox->rxq); | ||
399 | |||
400 | free_irq(mbox->irq, mbox); | ||
401 | device_remove_file(&mbox->dev, &dev_attr_mbox); | ||
402 | class_unregister(&omap_mbox_class); | ||
403 | |||
404 | if (unlikely(mbox->ops->shutdown)) | ||
405 | mbox->ops->shutdown(mbox); | ||
406 | } | ||
407 | |||
408 | static struct omap_mbox **find_mboxes(const char *name) | ||
409 | { | ||
410 | struct omap_mbox **p; | ||
411 | |||
412 | for (p = &mboxes; *p; p = &(*p)->next) { | ||
413 | if (strcmp((*p)->name, name) == 0) | ||
414 | break; | ||
415 | } | ||
416 | |||
417 | return p; | ||
418 | } | ||
419 | |||
420 | struct omap_mbox *omap_mbox_get(const char *name) | ||
421 | { | ||
422 | struct omap_mbox *mbox; | ||
423 | int ret; | ||
424 | |||
425 | read_lock(&mboxes_lock); | ||
426 | mbox = *(find_mboxes(name)); | ||
427 | if (mbox == NULL) { | ||
428 | read_unlock(&mboxes_lock); | ||
429 | return ERR_PTR(-ENOENT); | ||
430 | } | ||
431 | |||
432 | read_unlock(&mboxes_lock); | ||
433 | |||
434 | ret = omap_mbox_init(mbox); | ||
435 | if (ret) | ||
436 | return ERR_PTR(-ENODEV); | ||
437 | |||
438 | return mbox; | ||
439 | } | ||
440 | EXPORT_SYMBOL(omap_mbox_get); | ||
441 | |||
442 | void omap_mbox_put(struct omap_mbox *mbox) | ||
443 | { | ||
444 | omap_mbox_fini(mbox); | ||
445 | } | ||
446 | EXPORT_SYMBOL(omap_mbox_put); | ||
447 | |||
448 | int omap_mbox_register(struct omap_mbox *mbox) | ||
449 | { | ||
450 | int ret = 0; | ||
451 | struct omap_mbox **tmp; | ||
452 | |||
453 | if (!mbox) | ||
454 | return -EINVAL; | ||
455 | if (mbox->next) | ||
456 | return -EBUSY; | ||
457 | |||
458 | write_lock(&mboxes_lock); | ||
459 | tmp = find_mboxes(mbox->name); | ||
460 | if (*tmp) | ||
461 | ret = -EBUSY; | ||
462 | else | ||
463 | *tmp = mbox; | ||
464 | write_unlock(&mboxes_lock); | ||
465 | |||
466 | return ret; | ||
467 | } | ||
468 | EXPORT_SYMBOL(omap_mbox_register); | ||
469 | |||
470 | int omap_mbox_unregister(struct omap_mbox *mbox) | ||
471 | { | ||
472 | struct omap_mbox **tmp; | ||
473 | |||
474 | write_lock(&mboxes_lock); | ||
475 | tmp = &mboxes; | ||
476 | while (*tmp) { | ||
477 | if (mbox == *tmp) { | ||
478 | *tmp = mbox->next; | ||
479 | mbox->next = NULL; | ||
480 | write_unlock(&mboxes_lock); | ||
481 | return 0; | ||
482 | } | ||
483 | tmp = &(*tmp)->next; | ||
484 | } | ||
485 | write_unlock(&mboxes_lock); | ||
486 | |||
487 | return -EINVAL; | ||
488 | } | ||
489 | EXPORT_SYMBOL(omap_mbox_unregister); | ||
490 | |||
491 | static int __init omap_mbox_class_init(void) | ||
492 | { | ||
493 | int ret = class_register(&omap_mbox_class); | ||
494 | if (!ret) | ||
495 | ret = class_create_file(&omap_mbox_class, &class_attr_mbox); | ||
496 | |||
497 | return ret; | ||
498 | } | ||
499 | |||
500 | static void __exit omap_mbox_class_exit(void) | ||
501 | { | ||
502 | class_remove_file(&omap_mbox_class, &class_attr_mbox); | ||
503 | class_unregister(&omap_mbox_class); | ||
504 | } | ||
505 | |||
506 | subsys_initcall(omap_mbox_class_init); | ||
507 | module_exit(omap_mbox_class_exit); | ||
508 | |||
509 | MODULE_LICENSE("GPL"); | ||