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Commit | Line | Data |
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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 | |
ce491cf8 | 34 | #include <plat/mailbox.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 | ||
5ed8d32e | 119 | static void mbox_tx_tasklet(unsigned long tx_data) |
340a614a | 120 | { |
5ed8d32e | 121 | struct omap_mbox *mbox = (struct omap_mbox *)tx_data; |
b5bebe41 OBC |
122 | struct omap_mbox_queue *mq = mbox->txq; |
123 | mbox_msg_t msg; | |
124 | int ret; | |
340a614a | 125 | |
b5bebe41 OBC |
126 | while (kfifo_len(&mq->fifo)) { |
127 | if (__mbox_poll_for_space(mbox)) { | |
eb18858e | 128 | omap_mbox_enable_irq(mbox, IRQ_TX); |
b5bebe41 | 129 | break; |
340a614a | 130 | } |
b5bebe41 OBC |
131 | |
132 | ret = kfifo_out(&mq->fifo, (unsigned char *)&msg, | |
133 | sizeof(msg)); | |
134 | WARN_ON(ret != sizeof(msg)); | |
135 | ||
136 | mbox_fifo_write(mbox, msg); | |
340a614a HD |
137 | } |
138 | } | |
139 | ||
140 | /* | |
141 | * Message receiver(workqueue) | |
142 | */ | |
143 | static void mbox_rx_work(struct work_struct *work) | |
144 | { | |
145 | struct omap_mbox_queue *mq = | |
146 | container_of(work, struct omap_mbox_queue, work); | |
340a614a | 147 | mbox_msg_t msg; |
b5bebe41 OBC |
148 | int len; |
149 | ||
150 | while (kfifo_len(&mq->fifo) >= sizeof(msg)) { | |
151 | len = kfifo_out(&mq->fifo, (unsigned char *)&msg, sizeof(msg)); | |
152 | WARN_ON(len != sizeof(msg)); | |
340a614a | 153 | |
58256307 KH |
154 | blocking_notifier_call_chain(&mq->mbox->notifier, len, |
155 | (void *)msg); | |
d2295042 FGL |
156 | spin_lock_irq(&mq->lock); |
157 | if (mq->full) { | |
158 | mq->full = false; | |
159 | omap_mbox_enable_irq(mq->mbox, IRQ_RX); | |
160 | } | |
161 | spin_unlock_irq(&mq->lock); | |
340a614a HD |
162 | } |
163 | } | |
164 | ||
165 | /* | |
166 | * Mailbox interrupt handler | |
167 | */ | |
340a614a HD |
168 | static void __mbox_tx_interrupt(struct omap_mbox *mbox) |
169 | { | |
eb18858e | 170 | omap_mbox_disable_irq(mbox, IRQ_TX); |
340a614a | 171 | ack_mbox_irq(mbox, IRQ_TX); |
5ed8d32e | 172 | tasklet_schedule(&mbox->txq->tasklet); |
340a614a HD |
173 | } |
174 | ||
175 | static void __mbox_rx_interrupt(struct omap_mbox *mbox) | |
176 | { | |
b5bebe41 | 177 | struct omap_mbox_queue *mq = mbox->rxq; |
340a614a | 178 | mbox_msg_t msg; |
b5bebe41 | 179 | int len; |
340a614a | 180 | |
340a614a | 181 | while (!mbox_fifo_empty(mbox)) { |
b5bebe41 | 182 | if (unlikely(kfifo_avail(&mq->fifo) < sizeof(msg))) { |
1ea5d6d1 | 183 | omap_mbox_disable_irq(mbox, IRQ_RX); |
d2295042 | 184 | mq->full = true; |
340a614a | 185 | goto nomem; |
1ea5d6d1 | 186 | } |
340a614a HD |
187 | |
188 | msg = mbox_fifo_read(mbox); | |
340a614a | 189 | |
b5bebe41 OBC |
190 | len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg)); |
191 | WARN_ON(len != sizeof(msg)); | |
340a614a | 192 | |
340a614a HD |
193 | if (mbox->ops->type == OMAP_MBOX_TYPE1) |
194 | break; | |
195 | } | |
196 | ||
197 | /* no more messages in the fifo. clear IRQ source. */ | |
198 | ack_mbox_irq(mbox, IRQ_RX); | |
f48cca87 | 199 | nomem: |
c4873005 | 200 | schedule_work(&mbox->rxq->work); |
340a614a HD |
201 | } |
202 | ||
203 | static irqreturn_t mbox_interrupt(int irq, void *p) | |
204 | { | |
2a7057e3 | 205 | struct omap_mbox *mbox = p; |
340a614a HD |
206 | |
207 | if (is_mbox_irq(mbox, IRQ_TX)) | |
208 | __mbox_tx_interrupt(mbox); | |
209 | ||
210 | if (is_mbox_irq(mbox, IRQ_RX)) | |
211 | __mbox_rx_interrupt(mbox); | |
212 | ||
213 | return IRQ_HANDLED; | |
214 | } | |
215 | ||
340a614a | 216 | static struct omap_mbox_queue *mbox_queue_alloc(struct omap_mbox *mbox, |
5ed8d32e S |
217 | void (*work) (struct work_struct *), |
218 | void (*tasklet)(unsigned long)) | |
340a614a | 219 | { |
340a614a HD |
220 | struct omap_mbox_queue *mq; |
221 | ||
222 | mq = kzalloc(sizeof(struct omap_mbox_queue), GFP_KERNEL); | |
223 | if (!mq) | |
224 | return NULL; | |
225 | ||
226 | spin_lock_init(&mq->lock); | |
227 | ||
b5bebe41 | 228 | if (kfifo_alloc(&mq->fifo, mbox_kfifo_size, GFP_KERNEL)) |
340a614a | 229 | goto error; |
340a614a | 230 | |
5ed8d32e S |
231 | if (work) |
232 | INIT_WORK(&mq->work, work); | |
340a614a | 233 | |
5ed8d32e S |
234 | if (tasklet) |
235 | tasklet_init(&mq->tasklet, tasklet, (unsigned long)mbox); | |
340a614a HD |
236 | return mq; |
237 | error: | |
238 | kfree(mq); | |
239 | return NULL; | |
240 | } | |
241 | ||
242 | static void mbox_queue_free(struct omap_mbox_queue *q) | |
243 | { | |
b5bebe41 | 244 | kfifo_free(&q->fifo); |
340a614a HD |
245 | kfree(q); |
246 | } | |
247 | ||
c7c158e5 | 248 | static int omap_mbox_startup(struct omap_mbox *mbox) |
340a614a | 249 | { |
5f00ec64 | 250 | int ret = 0; |
340a614a HD |
251 | struct omap_mbox_queue *mq; |
252 | ||
58256307 KH |
253 | mutex_lock(&mbox_configured_lock); |
254 | if (!mbox_configured++) { | |
255 | if (likely(mbox->ops->startup)) { | |
5f00ec64 | 256 | ret = mbox->ops->startup(mbox); |
58256307 KH |
257 | if (unlikely(ret)) |
258 | goto fail_startup; | |
259 | } else | |
260 | goto fail_startup; | |
340a614a HD |
261 | } |
262 | ||
58256307 KH |
263 | if (!mbox->use_count++) { |
264 | ret = request_irq(mbox->irq, mbox_interrupt, IRQF_SHARED, | |
265 | mbox->name, mbox); | |
266 | if (unlikely(ret)) { | |
267 | pr_err("failed to register mailbox interrupt:%d\n", | |
268 | ret); | |
269 | goto fail_request_irq; | |
270 | } | |
271 | mq = mbox_queue_alloc(mbox, NULL, mbox_tx_tasklet); | |
272 | if (!mq) { | |
273 | ret = -ENOMEM; | |
274 | goto fail_alloc_txq; | |
275 | } | |
276 | mbox->txq = mq; | |
340a614a | 277 | |
58256307 KH |
278 | mq = mbox_queue_alloc(mbox, mbox_rx_work, NULL); |
279 | if (!mq) { | |
280 | ret = -ENOMEM; | |
281 | goto fail_alloc_rxq; | |
282 | } | |
283 | mbox->rxq = mq; | |
284 | mq->mbox = mbox; | |
1d8a0e96 JG |
285 | |
286 | omap_mbox_enable_irq(mbox, IRQ_RX); | |
340a614a | 287 | } |
58256307 | 288 | mutex_unlock(&mbox_configured_lock); |
340a614a HD |
289 | return 0; |
290 | ||
ab66ac30 | 291 | fail_alloc_rxq: |
340a614a | 292 | mbox_queue_free(mbox->txq); |
ab66ac30 | 293 | fail_alloc_txq: |
340a614a | 294 | free_irq(mbox->irq, mbox); |
ab66ac30 | 295 | fail_request_irq: |
01072d8f | 296 | if (mbox->ops->shutdown) |
340a614a | 297 | mbox->ops->shutdown(mbox); |
58256307 KH |
298 | mbox->use_count--; |
299 | fail_startup: | |
300 | mbox_configured--; | |
301 | mutex_unlock(&mbox_configured_lock); | |
340a614a HD |
302 | return ret; |
303 | } | |
304 | ||
305 | static void omap_mbox_fini(struct omap_mbox *mbox) | |
306 | { | |
58256307 KH |
307 | mutex_lock(&mbox_configured_lock); |
308 | ||
309 | if (!--mbox->use_count) { | |
1d8a0e96 | 310 | omap_mbox_disable_irq(mbox, IRQ_RX); |
58256307 KH |
311 | free_irq(mbox->irq, mbox); |
312 | tasklet_kill(&mbox->txq->tasklet); | |
43829731 | 313 | flush_work(&mbox->rxq->work); |
58256307 KH |
314 | mbox_queue_free(mbox->txq); |
315 | mbox_queue_free(mbox->rxq); | |
316 | } | |
340a614a | 317 | |
58256307 KH |
318 | if (likely(mbox->ops->shutdown)) { |
319 | if (!--mbox_configured) | |
5f00ec64 | 320 | mbox->ops->shutdown(mbox); |
5f00ec64 | 321 | } |
58256307 KH |
322 | |
323 | mutex_unlock(&mbox_configured_lock); | |
340a614a HD |
324 | } |
325 | ||
58256307 | 326 | struct omap_mbox *omap_mbox_get(const char *name, struct notifier_block *nb) |
340a614a | 327 | { |
c0377320 KH |
328 | struct omap_mbox *_mbox, *mbox = NULL; |
329 | int i, ret; | |
340a614a | 330 | |
9c80c8cd FC |
331 | if (!mboxes) |
332 | return ERR_PTR(-EINVAL); | |
340a614a | 333 | |
c0377320 KH |
334 | for (i = 0; (_mbox = mboxes[i]); i++) { |
335 | if (!strcmp(_mbox->name, name)) { | |
336 | mbox = _mbox; | |
9c80c8cd | 337 | break; |
c0377320 KH |
338 | } |
339 | } | |
9c80c8cd FC |
340 | |
341 | if (!mbox) | |
342 | return ERR_PTR(-ENOENT); | |
340a614a | 343 | |
58256307 KH |
344 | if (nb) |
345 | blocking_notifier_chain_register(&mbox->notifier, nb); | |
346 | ||
1d8a0e96 JG |
347 | ret = omap_mbox_startup(mbox); |
348 | if (ret) { | |
349 | blocking_notifier_chain_unregister(&mbox->notifier, nb); | |
350 | return ERR_PTR(-ENODEV); | |
351 | } | |
352 | ||
340a614a HD |
353 | return mbox; |
354 | } | |
355 | EXPORT_SYMBOL(omap_mbox_get); | |
356 | ||
58256307 | 357 | void omap_mbox_put(struct omap_mbox *mbox, struct notifier_block *nb) |
340a614a | 358 | { |
58256307 | 359 | blocking_notifier_chain_unregister(&mbox->notifier, nb); |
340a614a HD |
360 | omap_mbox_fini(mbox); |
361 | } | |
362 | EXPORT_SYMBOL(omap_mbox_put); | |
363 | ||
6b233985 HD |
364 | static struct class omap_mbox_class = { .name = "mbox", }; |
365 | ||
9c80c8cd | 366 | int omap_mbox_register(struct device *parent, struct omap_mbox **list) |
340a614a | 367 | { |
9c80c8cd FC |
368 | int ret; |
369 | int i; | |
340a614a | 370 | |
9c80c8cd FC |
371 | mboxes = list; |
372 | if (!mboxes) | |
340a614a | 373 | return -EINVAL; |
340a614a | 374 | |
9c80c8cd FC |
375 | for (i = 0; mboxes[i]; i++) { |
376 | struct omap_mbox *mbox = mboxes[i]; | |
377 | mbox->dev = device_create(&omap_mbox_class, | |
378 | parent, 0, mbox, "%s", mbox->name); | |
379 | if (IS_ERR(mbox->dev)) { | |
380 | ret = PTR_ERR(mbox->dev); | |
381 | goto err_out; | |
382 | } | |
58256307 KH |
383 | |
384 | BLOCKING_INIT_NOTIFIER_HEAD(&mbox->notifier); | |
9c80c8cd | 385 | } |
f48cca87 HD |
386 | return 0; |
387 | ||
9c80c8cd FC |
388 | err_out: |
389 | while (i--) | |
390 | device_unregister(mboxes[i]->dev); | |
340a614a HD |
391 | return ret; |
392 | } | |
393 | EXPORT_SYMBOL(omap_mbox_register); | |
394 | ||
9c80c8cd | 395 | int omap_mbox_unregister(void) |
340a614a | 396 | { |
9c80c8cd | 397 | int i; |
340a614a | 398 | |
9c80c8cd FC |
399 | if (!mboxes) |
400 | return -EINVAL; | |
401 | ||
402 | for (i = 0; mboxes[i]; i++) | |
403 | device_unregister(mboxes[i]->dev); | |
404 | mboxes = NULL; | |
405 | return 0; | |
340a614a HD |
406 | } |
407 | EXPORT_SYMBOL(omap_mbox_unregister); | |
408 | ||
c7c158e5 | 409 | static int __init omap_mbox_init(void) |
340a614a | 410 | { |
6b233985 HD |
411 | int err; |
412 | ||
413 | err = class_register(&omap_mbox_class); | |
414 | if (err) | |
415 | return err; | |
416 | ||
b5bebe41 OBC |
417 | /* kfifo size sanity check: alignment and minimal size */ |
418 | mbox_kfifo_size = ALIGN(mbox_kfifo_size, sizeof(mbox_msg_t)); | |
ab66ac30 KH |
419 | mbox_kfifo_size = max_t(unsigned int, mbox_kfifo_size, |
420 | sizeof(mbox_msg_t)); | |
b5bebe41 | 421 | |
c7c158e5 | 422 | return 0; |
340a614a | 423 | } |
6b233985 | 424 | subsys_initcall(omap_mbox_init); |
340a614a | 425 | |
c7c158e5 | 426 | static void __exit omap_mbox_exit(void) |
340a614a | 427 | { |
6b233985 | 428 | class_unregister(&omap_mbox_class); |
340a614a | 429 | } |
c7c158e5 | 430 | module_exit(omap_mbox_exit); |
340a614a | 431 | |
f48cca87 HD |
432 | MODULE_LICENSE("GPL v2"); |
433 | MODULE_DESCRIPTION("omap mailbox: interrupt driven messaging"); | |
f375325a OBC |
434 | MODULE_AUTHOR("Toshihiro Kobayashi"); |
435 | MODULE_AUTHOR("Hiroshi DOYU"); |