Commit | Line | Data |
---|---|---|
340a614a HD |
1 | /* |
2 | * OMAP mailbox driver | |
3 | * | |
f48cca87 | 4 | * Copyright (C) 2006-2009 Nokia Corporation. All rights reserved. |
340a614a | 5 | * |
f48cca87 | 6 | * Contact: Hiroshi DOYU <Hiroshi.DOYU@nokia.com> |
340a614a HD |
7 | * |
8 | * This program is free software; you can redistribute it and/or | |
9 | * modify it under the terms of the GNU General Public License | |
10 | * version 2 as published by the Free Software Foundation. | |
11 | * | |
12 | * This program is distributed in the hope that it will be useful, but | |
13 | * WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
15 | * General Public License for more details. | |
16 | * | |
17 | * You should have received a copy of the GNU General Public License | |
18 | * along with this program; if not, write to the Free Software | |
19 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA | |
20 | * 02110-1301 USA | |
21 | * | |
22 | */ | |
23 | ||
340a614a | 24 | #include <linux/interrupt.h> |
b3e69146 FC |
25 | #include <linux/spinlock.h> |
26 | #include <linux/mutex.h> | |
340a614a | 27 | #include <linux/delay.h> |
5a0e3ad6 | 28 | #include <linux/slab.h> |
b5bebe41 OBC |
29 | #include <linux/kfifo.h> |
30 | #include <linux/err.h> | |
58256307 | 31 | #include <linux/notifier.h> |
73017a54 | 32 | #include <linux/module.h> |
8dff0fa5 | 33 | |
c869c75c | 34 | #include "omap-mbox.h" |
340a614a | 35 | |
9c80c8cd | 36 | static struct omap_mbox **mboxes; |
340a614a | 37 | |
5f00ec64 | 38 | static int mbox_configured; |
72b917ef | 39 | static DEFINE_MUTEX(mbox_configured_lock); |
5f00ec64 | 40 | |
b5bebe41 OBC |
41 | static unsigned int mbox_kfifo_size = CONFIG_OMAP_MBOX_KFIFO_SIZE; |
42 | module_param(mbox_kfifo_size, uint, S_IRUGO); | |
43 | MODULE_PARM_DESC(mbox_kfifo_size, "Size of omap's mailbox kfifo (bytes)"); | |
44 | ||
9ae0ee00 HD |
45 | /* Mailbox FIFO handle functions */ |
46 | static inline mbox_msg_t mbox_fifo_read(struct omap_mbox *mbox) | |
47 | { | |
48 | return mbox->ops->fifo_read(mbox); | |
49 | } | |
50 | static inline void mbox_fifo_write(struct omap_mbox *mbox, mbox_msg_t msg) | |
51 | { | |
52 | mbox->ops->fifo_write(mbox, msg); | |
53 | } | |
54 | static inline int mbox_fifo_empty(struct omap_mbox *mbox) | |
55 | { | |
56 | return mbox->ops->fifo_empty(mbox); | |
57 | } | |
58 | static inline int mbox_fifo_full(struct omap_mbox *mbox) | |
59 | { | |
60 | return mbox->ops->fifo_full(mbox); | |
61 | } | |
62 | ||
63 | /* Mailbox IRQ handle functions */ | |
9ae0ee00 HD |
64 | static inline void ack_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq) |
65 | { | |
66 | if (mbox->ops->ack_irq) | |
67 | mbox->ops->ack_irq(mbox, irq); | |
68 | } | |
69 | static inline int is_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq) | |
70 | { | |
71 | return mbox->ops->is_irq(mbox, irq); | |
72 | } | |
73 | ||
340a614a HD |
74 | /* |
75 | * message sender | |
76 | */ | |
b5bebe41 | 77 | static int __mbox_poll_for_space(struct omap_mbox *mbox) |
340a614a HD |
78 | { |
79 | int ret = 0, i = 1000; | |
80 | ||
81 | while (mbox_fifo_full(mbox)) { | |
82 | if (mbox->ops->type == OMAP_MBOX_TYPE2) | |
83 | return -1; | |
84 | if (--i == 0) | |
85 | return -1; | |
86 | udelay(1); | |
87 | } | |
340a614a HD |
88 | return ret; |
89 | } | |
90 | ||
b2b6362e | 91 | int omap_mbox_msg_send(struct omap_mbox *mbox, mbox_msg_t msg) |
340a614a | 92 | { |
b5bebe41 OBC |
93 | struct omap_mbox_queue *mq = mbox->txq; |
94 | int ret = 0, len; | |
5ed8d32e | 95 | |
a42743c2 | 96 | spin_lock_bh(&mq->lock); |
ec24751a | 97 | |
b5bebe41 OBC |
98 | if (kfifo_avail(&mq->fifo) < sizeof(msg)) { |
99 | ret = -ENOMEM; | |
100 | goto out; | |
101 | } | |
102 | ||
a42743c2 KH |
103 | if (kfifo_is_empty(&mq->fifo) && !__mbox_poll_for_space(mbox)) { |
104 | mbox_fifo_write(mbox, msg); | |
105 | goto out; | |
106 | } | |
107 | ||
b5bebe41 OBC |
108 | len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg)); |
109 | WARN_ON(len != sizeof(msg)); | |
340a614a | 110 | |
5ed8d32e | 111 | tasklet_schedule(&mbox->txq->tasklet); |
340a614a | 112 | |
b5bebe41 | 113 | out: |
a42743c2 | 114 | spin_unlock_bh(&mq->lock); |
b5bebe41 | 115 | return ret; |
340a614a HD |
116 | } |
117 | EXPORT_SYMBOL(omap_mbox_msg_send); | |
118 | ||
c869c75c SA |
119 | void omap_mbox_save_ctx(struct omap_mbox *mbox) |
120 | { | |
121 | if (!mbox->ops->save_ctx) { | |
122 | dev_err(mbox->dev, "%s:\tno save\n", __func__); | |
123 | return; | |
124 | } | |
125 | ||
126 | mbox->ops->save_ctx(mbox); | |
127 | } | |
128 | EXPORT_SYMBOL(omap_mbox_save_ctx); | |
129 | ||
130 | void omap_mbox_restore_ctx(struct omap_mbox *mbox) | |
131 | { | |
132 | if (!mbox->ops->restore_ctx) { | |
133 | dev_err(mbox->dev, "%s:\tno restore\n", __func__); | |
134 | return; | |
135 | } | |
136 | ||
137 | mbox->ops->restore_ctx(mbox); | |
138 | } | |
139 | EXPORT_SYMBOL(omap_mbox_restore_ctx); | |
140 | ||
141 | void omap_mbox_enable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq) | |
142 | { | |
143 | mbox->ops->enable_irq(mbox, irq); | |
144 | } | |
145 | EXPORT_SYMBOL(omap_mbox_enable_irq); | |
146 | ||
147 | void omap_mbox_disable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq) | |
148 | { | |
149 | mbox->ops->disable_irq(mbox, irq); | |
150 | } | |
151 | EXPORT_SYMBOL(omap_mbox_disable_irq); | |
152 | ||
5ed8d32e | 153 | static void mbox_tx_tasklet(unsigned long tx_data) |
340a614a | 154 | { |
5ed8d32e | 155 | struct omap_mbox *mbox = (struct omap_mbox *)tx_data; |
b5bebe41 OBC |
156 | struct omap_mbox_queue *mq = mbox->txq; |
157 | mbox_msg_t msg; | |
158 | int ret; | |
340a614a | 159 | |
b5bebe41 OBC |
160 | while (kfifo_len(&mq->fifo)) { |
161 | if (__mbox_poll_for_space(mbox)) { | |
eb18858e | 162 | omap_mbox_enable_irq(mbox, IRQ_TX); |
b5bebe41 | 163 | break; |
340a614a | 164 | } |
b5bebe41 OBC |
165 | |
166 | ret = kfifo_out(&mq->fifo, (unsigned char *)&msg, | |
167 | sizeof(msg)); | |
168 | WARN_ON(ret != sizeof(msg)); | |
169 | ||
170 | mbox_fifo_write(mbox, msg); | |
340a614a HD |
171 | } |
172 | } | |
173 | ||
174 | /* | |
175 | * Message receiver(workqueue) | |
176 | */ | |
177 | static void mbox_rx_work(struct work_struct *work) | |
178 | { | |
179 | struct omap_mbox_queue *mq = | |
180 | container_of(work, struct omap_mbox_queue, work); | |
340a614a | 181 | mbox_msg_t msg; |
b5bebe41 OBC |
182 | int len; |
183 | ||
184 | while (kfifo_len(&mq->fifo) >= sizeof(msg)) { | |
185 | len = kfifo_out(&mq->fifo, (unsigned char *)&msg, sizeof(msg)); | |
186 | WARN_ON(len != sizeof(msg)); | |
340a614a | 187 | |
58256307 KH |
188 | blocking_notifier_call_chain(&mq->mbox->notifier, len, |
189 | (void *)msg); | |
d2295042 FGL |
190 | spin_lock_irq(&mq->lock); |
191 | if (mq->full) { | |
192 | mq->full = false; | |
193 | omap_mbox_enable_irq(mq->mbox, IRQ_RX); | |
194 | } | |
195 | spin_unlock_irq(&mq->lock); | |
340a614a HD |
196 | } |
197 | } | |
198 | ||
199 | /* | |
200 | * Mailbox interrupt handler | |
201 | */ | |
340a614a HD |
202 | static void __mbox_tx_interrupt(struct omap_mbox *mbox) |
203 | { | |
eb18858e | 204 | omap_mbox_disable_irq(mbox, IRQ_TX); |
340a614a | 205 | ack_mbox_irq(mbox, IRQ_TX); |
5ed8d32e | 206 | tasklet_schedule(&mbox->txq->tasklet); |
340a614a HD |
207 | } |
208 | ||
209 | static void __mbox_rx_interrupt(struct omap_mbox *mbox) | |
210 | { | |
b5bebe41 | 211 | struct omap_mbox_queue *mq = mbox->rxq; |
340a614a | 212 | mbox_msg_t msg; |
b5bebe41 | 213 | int len; |
340a614a | 214 | |
340a614a | 215 | while (!mbox_fifo_empty(mbox)) { |
b5bebe41 | 216 | if (unlikely(kfifo_avail(&mq->fifo) < sizeof(msg))) { |
1ea5d6d1 | 217 | omap_mbox_disable_irq(mbox, IRQ_RX); |
d2295042 | 218 | mq->full = true; |
340a614a | 219 | goto nomem; |
1ea5d6d1 | 220 | } |
340a614a HD |
221 | |
222 | msg = mbox_fifo_read(mbox); | |
340a614a | 223 | |
b5bebe41 OBC |
224 | len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg)); |
225 | WARN_ON(len != sizeof(msg)); | |
340a614a | 226 | |
340a614a HD |
227 | if (mbox->ops->type == OMAP_MBOX_TYPE1) |
228 | break; | |
229 | } | |
230 | ||
231 | /* no more messages in the fifo. clear IRQ source. */ | |
232 | ack_mbox_irq(mbox, IRQ_RX); | |
f48cca87 | 233 | nomem: |
c4873005 | 234 | schedule_work(&mbox->rxq->work); |
340a614a HD |
235 | } |
236 | ||
237 | static irqreturn_t mbox_interrupt(int irq, void *p) | |
238 | { | |
2a7057e3 | 239 | struct omap_mbox *mbox = p; |
340a614a HD |
240 | |
241 | if (is_mbox_irq(mbox, IRQ_TX)) | |
242 | __mbox_tx_interrupt(mbox); | |
243 | ||
244 | if (is_mbox_irq(mbox, IRQ_RX)) | |
245 | __mbox_rx_interrupt(mbox); | |
246 | ||
247 | return IRQ_HANDLED; | |
248 | } | |
249 | ||
340a614a | 250 | static struct omap_mbox_queue *mbox_queue_alloc(struct omap_mbox *mbox, |
5ed8d32e S |
251 | void (*work) (struct work_struct *), |
252 | void (*tasklet)(unsigned long)) | |
340a614a | 253 | { |
340a614a HD |
254 | struct omap_mbox_queue *mq; |
255 | ||
256 | mq = kzalloc(sizeof(struct omap_mbox_queue), GFP_KERNEL); | |
257 | if (!mq) | |
258 | return NULL; | |
259 | ||
260 | spin_lock_init(&mq->lock); | |
261 | ||
b5bebe41 | 262 | if (kfifo_alloc(&mq->fifo, mbox_kfifo_size, GFP_KERNEL)) |
340a614a | 263 | goto error; |
340a614a | 264 | |
5ed8d32e S |
265 | if (work) |
266 | INIT_WORK(&mq->work, work); | |
340a614a | 267 | |
5ed8d32e S |
268 | if (tasklet) |
269 | tasklet_init(&mq->tasklet, tasklet, (unsigned long)mbox); | |
340a614a HD |
270 | return mq; |
271 | error: | |
272 | kfree(mq); | |
273 | return NULL; | |
274 | } | |
275 | ||
276 | static void mbox_queue_free(struct omap_mbox_queue *q) | |
277 | { | |
b5bebe41 | 278 | kfifo_free(&q->fifo); |
340a614a HD |
279 | kfree(q); |
280 | } | |
281 | ||
c7c158e5 | 282 | static int omap_mbox_startup(struct omap_mbox *mbox) |
340a614a | 283 | { |
5f00ec64 | 284 | int ret = 0; |
340a614a HD |
285 | struct omap_mbox_queue *mq; |
286 | ||
58256307 KH |
287 | mutex_lock(&mbox_configured_lock); |
288 | if (!mbox_configured++) { | |
289 | if (likely(mbox->ops->startup)) { | |
5f00ec64 | 290 | ret = mbox->ops->startup(mbox); |
58256307 KH |
291 | if (unlikely(ret)) |
292 | goto fail_startup; | |
293 | } else | |
294 | goto fail_startup; | |
340a614a HD |
295 | } |
296 | ||
58256307 | 297 | if (!mbox->use_count++) { |
58256307 KH |
298 | mq = mbox_queue_alloc(mbox, NULL, mbox_tx_tasklet); |
299 | if (!mq) { | |
300 | ret = -ENOMEM; | |
301 | goto fail_alloc_txq; | |
302 | } | |
303 | mbox->txq = mq; | |
340a614a | 304 | |
58256307 KH |
305 | mq = mbox_queue_alloc(mbox, mbox_rx_work, NULL); |
306 | if (!mq) { | |
307 | ret = -ENOMEM; | |
308 | goto fail_alloc_rxq; | |
309 | } | |
310 | mbox->rxq = mq; | |
311 | mq->mbox = mbox; | |
ecf305cf SA |
312 | ret = request_irq(mbox->irq, mbox_interrupt, IRQF_SHARED, |
313 | mbox->name, mbox); | |
314 | if (unlikely(ret)) { | |
315 | pr_err("failed to register mailbox interrupt:%d\n", | |
316 | ret); | |
317 | goto fail_request_irq; | |
318 | } | |
1d8a0e96 JG |
319 | |
320 | omap_mbox_enable_irq(mbox, IRQ_RX); | |
340a614a | 321 | } |
58256307 | 322 | mutex_unlock(&mbox_configured_lock); |
340a614a HD |
323 | return 0; |
324 | ||
ecf305cf SA |
325 | fail_request_irq: |
326 | mbox_queue_free(mbox->rxq); | |
ab66ac30 | 327 | fail_alloc_rxq: |
340a614a | 328 | mbox_queue_free(mbox->txq); |
ab66ac30 | 329 | fail_alloc_txq: |
01072d8f | 330 | if (mbox->ops->shutdown) |
340a614a | 331 | mbox->ops->shutdown(mbox); |
58256307 KH |
332 | mbox->use_count--; |
333 | fail_startup: | |
334 | mbox_configured--; | |
335 | mutex_unlock(&mbox_configured_lock); | |
340a614a HD |
336 | return ret; |
337 | } | |
338 | ||
339 | static void omap_mbox_fini(struct omap_mbox *mbox) | |
340 | { | |
58256307 KH |
341 | mutex_lock(&mbox_configured_lock); |
342 | ||
343 | if (!--mbox->use_count) { | |
1d8a0e96 | 344 | omap_mbox_disable_irq(mbox, IRQ_RX); |
58256307 KH |
345 | free_irq(mbox->irq, mbox); |
346 | tasklet_kill(&mbox->txq->tasklet); | |
43829731 | 347 | flush_work(&mbox->rxq->work); |
58256307 KH |
348 | mbox_queue_free(mbox->txq); |
349 | mbox_queue_free(mbox->rxq); | |
350 | } | |
340a614a | 351 | |
58256307 KH |
352 | if (likely(mbox->ops->shutdown)) { |
353 | if (!--mbox_configured) | |
5f00ec64 | 354 | mbox->ops->shutdown(mbox); |
5f00ec64 | 355 | } |
58256307 KH |
356 | |
357 | mutex_unlock(&mbox_configured_lock); | |
340a614a HD |
358 | } |
359 | ||
58256307 | 360 | struct omap_mbox *omap_mbox_get(const char *name, struct notifier_block *nb) |
340a614a | 361 | { |
c0377320 KH |
362 | struct omap_mbox *_mbox, *mbox = NULL; |
363 | int i, ret; | |
340a614a | 364 | |
9c80c8cd FC |
365 | if (!mboxes) |
366 | return ERR_PTR(-EINVAL); | |
340a614a | 367 | |
c0377320 KH |
368 | for (i = 0; (_mbox = mboxes[i]); i++) { |
369 | if (!strcmp(_mbox->name, name)) { | |
370 | mbox = _mbox; | |
9c80c8cd | 371 | break; |
c0377320 KH |
372 | } |
373 | } | |
9c80c8cd FC |
374 | |
375 | if (!mbox) | |
376 | return ERR_PTR(-ENOENT); | |
340a614a | 377 | |
58256307 KH |
378 | if (nb) |
379 | blocking_notifier_chain_register(&mbox->notifier, nb); | |
380 | ||
1d8a0e96 JG |
381 | ret = omap_mbox_startup(mbox); |
382 | if (ret) { | |
383 | blocking_notifier_chain_unregister(&mbox->notifier, nb); | |
384 | return ERR_PTR(-ENODEV); | |
385 | } | |
386 | ||
340a614a HD |
387 | return mbox; |
388 | } | |
389 | EXPORT_SYMBOL(omap_mbox_get); | |
390 | ||
58256307 | 391 | void omap_mbox_put(struct omap_mbox *mbox, struct notifier_block *nb) |
340a614a | 392 | { |
58256307 | 393 | blocking_notifier_chain_unregister(&mbox->notifier, nb); |
340a614a HD |
394 | omap_mbox_fini(mbox); |
395 | } | |
396 | EXPORT_SYMBOL(omap_mbox_put); | |
397 | ||
6b233985 HD |
398 | static struct class omap_mbox_class = { .name = "mbox", }; |
399 | ||
9c80c8cd | 400 | int omap_mbox_register(struct device *parent, struct omap_mbox **list) |
340a614a | 401 | { |
9c80c8cd FC |
402 | int ret; |
403 | int i; | |
340a614a | 404 | |
9c80c8cd FC |
405 | mboxes = list; |
406 | if (!mboxes) | |
340a614a | 407 | return -EINVAL; |
340a614a | 408 | |
9c80c8cd FC |
409 | for (i = 0; mboxes[i]; i++) { |
410 | struct omap_mbox *mbox = mboxes[i]; | |
411 | mbox->dev = device_create(&omap_mbox_class, | |
412 | parent, 0, mbox, "%s", mbox->name); | |
413 | if (IS_ERR(mbox->dev)) { | |
414 | ret = PTR_ERR(mbox->dev); | |
415 | goto err_out; | |
416 | } | |
58256307 KH |
417 | |
418 | BLOCKING_INIT_NOTIFIER_HEAD(&mbox->notifier); | |
9c80c8cd | 419 | } |
f48cca87 HD |
420 | return 0; |
421 | ||
9c80c8cd FC |
422 | err_out: |
423 | while (i--) | |
424 | device_unregister(mboxes[i]->dev); | |
340a614a HD |
425 | return ret; |
426 | } | |
427 | EXPORT_SYMBOL(omap_mbox_register); | |
428 | ||
9c80c8cd | 429 | int omap_mbox_unregister(void) |
340a614a | 430 | { |
9c80c8cd | 431 | int i; |
340a614a | 432 | |
9c80c8cd FC |
433 | if (!mboxes) |
434 | return -EINVAL; | |
435 | ||
436 | for (i = 0; mboxes[i]; i++) | |
437 | device_unregister(mboxes[i]->dev); | |
438 | mboxes = NULL; | |
439 | return 0; | |
340a614a HD |
440 | } |
441 | EXPORT_SYMBOL(omap_mbox_unregister); | |
442 | ||
c7c158e5 | 443 | static int __init omap_mbox_init(void) |
340a614a | 444 | { |
6b233985 HD |
445 | int err; |
446 | ||
447 | err = class_register(&omap_mbox_class); | |
448 | if (err) | |
449 | return err; | |
450 | ||
b5bebe41 OBC |
451 | /* kfifo size sanity check: alignment and minimal size */ |
452 | mbox_kfifo_size = ALIGN(mbox_kfifo_size, sizeof(mbox_msg_t)); | |
ab66ac30 KH |
453 | mbox_kfifo_size = max_t(unsigned int, mbox_kfifo_size, |
454 | sizeof(mbox_msg_t)); | |
b5bebe41 | 455 | |
c7c158e5 | 456 | return 0; |
340a614a | 457 | } |
6b233985 | 458 | subsys_initcall(omap_mbox_init); |
340a614a | 459 | |
c7c158e5 | 460 | static void __exit omap_mbox_exit(void) |
340a614a | 461 | { |
6b233985 | 462 | class_unregister(&omap_mbox_class); |
340a614a | 463 | } |
c7c158e5 | 464 | module_exit(omap_mbox_exit); |
340a614a | 465 | |
f48cca87 HD |
466 | MODULE_LICENSE("GPL v2"); |
467 | MODULE_DESCRIPTION("omap mailbox: interrupt driven messaging"); | |
f375325a OBC |
468 | MODULE_AUTHOR("Toshihiro Kobayashi"); |
469 | MODULE_AUTHOR("Hiroshi DOYU"); |