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/module.h> |
340a614a HD |
25 | #include <linux/interrupt.h> |
26 | #include <linux/device.h> | |
340a614a | 27 | #include <linux/delay.h> |
5a0e3ad6 | 28 | #include <linux/slab.h> |
8dff0fa5 | 29 | |
ce491cf8 | 30 | #include <plat/mailbox.h> |
340a614a | 31 | |
8250a5c3 | 32 | static struct workqueue_struct *mboxd; |
340a614a HD |
33 | static struct omap_mbox *mboxes; |
34 | static DEFINE_RWLOCK(mboxes_lock); | |
35 | ||
5f00ec64 S |
36 | static int mbox_configured; |
37 | ||
9ae0ee00 HD |
38 | /* Mailbox FIFO handle functions */ |
39 | static inline mbox_msg_t mbox_fifo_read(struct omap_mbox *mbox) | |
40 | { | |
41 | return mbox->ops->fifo_read(mbox); | |
42 | } | |
43 | static inline void mbox_fifo_write(struct omap_mbox *mbox, mbox_msg_t msg) | |
44 | { | |
45 | mbox->ops->fifo_write(mbox, msg); | |
46 | } | |
47 | static inline int mbox_fifo_empty(struct omap_mbox *mbox) | |
48 | { | |
49 | return mbox->ops->fifo_empty(mbox); | |
50 | } | |
51 | static inline int mbox_fifo_full(struct omap_mbox *mbox) | |
52 | { | |
53 | return mbox->ops->fifo_full(mbox); | |
54 | } | |
55 | ||
56 | /* Mailbox IRQ handle functions */ | |
9ae0ee00 HD |
57 | static inline void ack_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq) |
58 | { | |
59 | if (mbox->ops->ack_irq) | |
60 | mbox->ops->ack_irq(mbox, irq); | |
61 | } | |
62 | static inline int is_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq) | |
63 | { | |
64 | return mbox->ops->is_irq(mbox, irq); | |
65 | } | |
66 | ||
340a614a HD |
67 | /* |
68 | * message sender | |
69 | */ | |
c7c158e5 | 70 | static int __mbox_msg_send(struct omap_mbox *mbox, mbox_msg_t msg) |
340a614a HD |
71 | { |
72 | int ret = 0, i = 1000; | |
73 | ||
74 | while (mbox_fifo_full(mbox)) { | |
75 | if (mbox->ops->type == OMAP_MBOX_TYPE2) | |
76 | return -1; | |
77 | if (--i == 0) | |
78 | return -1; | |
79 | udelay(1); | |
80 | } | |
340a614a | 81 | mbox_fifo_write(mbox, msg); |
340a614a HD |
82 | return ret; |
83 | } | |
84 | ||
ec24751a | 85 | |
b2b6362e | 86 | int omap_mbox_msg_send(struct omap_mbox *mbox, mbox_msg_t msg) |
340a614a | 87 | { |
5ed8d32e | 88 | |
340a614a HD |
89 | struct request *rq; |
90 | struct request_queue *q = mbox->txq->queue; | |
ec24751a | 91 | |
340a614a | 92 | rq = blk_get_request(q, WRITE, GFP_ATOMIC); |
5ed8d32e | 93 | if (unlikely(!rq)) |
ec24751a | 94 | return -ENOMEM; |
340a614a | 95 | |
5ed8d32e S |
96 | blk_insert_request(q, rq, 0, (void *) msg); |
97 | tasklet_schedule(&mbox->txq->tasklet); | |
340a614a | 98 | |
ec24751a | 99 | return 0; |
340a614a HD |
100 | } |
101 | EXPORT_SYMBOL(omap_mbox_msg_send); | |
102 | ||
5ed8d32e | 103 | static void mbox_tx_tasklet(unsigned long tx_data) |
340a614a HD |
104 | { |
105 | int ret; | |
106 | struct request *rq; | |
5ed8d32e | 107 | struct omap_mbox *mbox = (struct omap_mbox *)tx_data; |
340a614a HD |
108 | struct request_queue *q = mbox->txq->queue; |
109 | ||
110 | while (1) { | |
ec24751a | 111 | |
9934c8c0 | 112 | rq = blk_fetch_request(q); |
340a614a HD |
113 | |
114 | if (!rq) | |
115 | break; | |
116 | ||
5ed8d32e | 117 | ret = __mbox_msg_send(mbox, (mbox_msg_t)rq->special); |
340a614a | 118 | if (ret) { |
eb18858e | 119 | omap_mbox_enable_irq(mbox, IRQ_TX); |
296b2f6a | 120 | blk_requeue_request(q, rq); |
340a614a HD |
121 | return; |
122 | } | |
5ed8d32e | 123 | blk_end_request_all(rq, 0); |
340a614a HD |
124 | } |
125 | } | |
126 | ||
127 | /* | |
128 | * Message receiver(workqueue) | |
129 | */ | |
130 | static void mbox_rx_work(struct work_struct *work) | |
131 | { | |
132 | struct omap_mbox_queue *mq = | |
133 | container_of(work, struct omap_mbox_queue, work); | |
134 | struct omap_mbox *mbox = mq->queue->queuedata; | |
135 | struct request_queue *q = mbox->rxq->queue; | |
136 | struct request *rq; | |
137 | mbox_msg_t msg; | |
138 | unsigned long flags; | |
139 | ||
340a614a HD |
140 | while (1) { |
141 | spin_lock_irqsave(q->queue_lock, flags); | |
9934c8c0 | 142 | rq = blk_fetch_request(q); |
340a614a HD |
143 | spin_unlock_irqrestore(q->queue_lock, flags); |
144 | if (!rq) | |
145 | break; | |
146 | ||
ec24751a | 147 | msg = (mbox_msg_t)rq->special; |
40cbbb78 | 148 | blk_end_request_all(rq, 0); |
340a614a HD |
149 | mbox->rxq->callback((void *)msg); |
150 | } | |
151 | } | |
152 | ||
153 | /* | |
154 | * Mailbox interrupt handler | |
155 | */ | |
bfe1f6ac | 156 | static void mbox_txq_fn(struct request_queue *q) |
340a614a HD |
157 | { |
158 | } | |
159 | ||
bfe1f6ac | 160 | static void mbox_rxq_fn(struct request_queue *q) |
340a614a HD |
161 | { |
162 | } | |
163 | ||
164 | static void __mbox_tx_interrupt(struct omap_mbox *mbox) | |
165 | { | |
eb18858e | 166 | omap_mbox_disable_irq(mbox, IRQ_TX); |
340a614a | 167 | ack_mbox_irq(mbox, IRQ_TX); |
5ed8d32e | 168 | tasklet_schedule(&mbox->txq->tasklet); |
340a614a HD |
169 | } |
170 | ||
171 | static void __mbox_rx_interrupt(struct omap_mbox *mbox) | |
172 | { | |
173 | struct request *rq; | |
174 | mbox_msg_t msg; | |
165125e1 | 175 | struct request_queue *q = mbox->rxq->queue; |
340a614a | 176 | |
340a614a HD |
177 | while (!mbox_fifo_empty(mbox)) { |
178 | rq = blk_get_request(q, WRITE, GFP_ATOMIC); | |
179 | if (unlikely(!rq)) | |
180 | goto nomem; | |
181 | ||
182 | msg = mbox_fifo_read(mbox); | |
340a614a | 183 | |
340a614a | 184 | |
ec24751a | 185 | blk_insert_request(q, rq, 0, (void *)msg); |
340a614a HD |
186 | if (mbox->ops->type == OMAP_MBOX_TYPE1) |
187 | break; | |
188 | } | |
189 | ||
190 | /* no more messages in the fifo. clear IRQ source. */ | |
191 | ack_mbox_irq(mbox, IRQ_RX); | |
f48cca87 | 192 | nomem: |
8250a5c3 | 193 | queue_work(mboxd, &mbox->rxq->work); |
340a614a HD |
194 | } |
195 | ||
196 | static irqreturn_t mbox_interrupt(int irq, void *p) | |
197 | { | |
2a7057e3 | 198 | struct omap_mbox *mbox = p; |
340a614a HD |
199 | |
200 | if (is_mbox_irq(mbox, IRQ_TX)) | |
201 | __mbox_tx_interrupt(mbox); | |
202 | ||
203 | if (is_mbox_irq(mbox, IRQ_RX)) | |
204 | __mbox_rx_interrupt(mbox); | |
205 | ||
206 | return IRQ_HANDLED; | |
207 | } | |
208 | ||
340a614a | 209 | static struct omap_mbox_queue *mbox_queue_alloc(struct omap_mbox *mbox, |
bfe1f6ac | 210 | request_fn_proc *proc, |
5ed8d32e S |
211 | void (*work) (struct work_struct *), |
212 | void (*tasklet)(unsigned long)) | |
340a614a | 213 | { |
165125e1 | 214 | struct request_queue *q; |
340a614a HD |
215 | struct omap_mbox_queue *mq; |
216 | ||
217 | mq = kzalloc(sizeof(struct omap_mbox_queue), GFP_KERNEL); | |
218 | if (!mq) | |
219 | return NULL; | |
220 | ||
221 | spin_lock_init(&mq->lock); | |
222 | ||
223 | q = blk_init_queue(proc, &mq->lock); | |
224 | if (!q) | |
225 | goto error; | |
226 | q->queuedata = mbox; | |
227 | mq->queue = q; | |
228 | ||
5ed8d32e S |
229 | if (work) |
230 | INIT_WORK(&mq->work, work); | |
340a614a | 231 | |
5ed8d32e S |
232 | if (tasklet) |
233 | tasklet_init(&mq->tasklet, tasklet, (unsigned long)mbox); | |
340a614a HD |
234 | return mq; |
235 | error: | |
236 | kfree(mq); | |
237 | return NULL; | |
238 | } | |
239 | ||
240 | static void mbox_queue_free(struct omap_mbox_queue *q) | |
241 | { | |
242 | blk_cleanup_queue(q->queue); | |
243 | kfree(q); | |
244 | } | |
245 | ||
c7c158e5 | 246 | static int omap_mbox_startup(struct omap_mbox *mbox) |
340a614a | 247 | { |
5f00ec64 | 248 | int ret = 0; |
340a614a HD |
249 | struct omap_mbox_queue *mq; |
250 | ||
251 | if (likely(mbox->ops->startup)) { | |
5f00ec64 S |
252 | write_lock(&mboxes_lock); |
253 | if (!mbox_configured) | |
254 | ret = mbox->ops->startup(mbox); | |
255 | ||
256 | if (unlikely(ret)) { | |
257 | write_unlock(&mboxes_lock); | |
340a614a | 258 | return ret; |
5f00ec64 S |
259 | } |
260 | mbox_configured++; | |
261 | write_unlock(&mboxes_lock); | |
340a614a HD |
262 | } |
263 | ||
5e683825 | 264 | ret = request_irq(mbox->irq, mbox_interrupt, IRQF_SHARED, |
340a614a HD |
265 | mbox->name, mbox); |
266 | if (unlikely(ret)) { | |
267 | printk(KERN_ERR | |
268 | "failed to register mailbox interrupt:%d\n", ret); | |
269 | goto fail_request_irq; | |
270 | } | |
340a614a | 271 | |
5ed8d32e | 272 | mq = mbox_queue_alloc(mbox, mbox_txq_fn, NULL, mbox_tx_tasklet); |
340a614a HD |
273 | if (!mq) { |
274 | ret = -ENOMEM; | |
275 | goto fail_alloc_txq; | |
276 | } | |
277 | mbox->txq = mq; | |
278 | ||
5ed8d32e | 279 | mq = mbox_queue_alloc(mbox, mbox_rxq_fn, mbox_rx_work, NULL); |
340a614a HD |
280 | if (!mq) { |
281 | ret = -ENOMEM; | |
282 | goto fail_alloc_rxq; | |
283 | } | |
284 | mbox->rxq = mq; | |
285 | ||
286 | return 0; | |
287 | ||
288 | fail_alloc_rxq: | |
289 | mbox_queue_free(mbox->txq); | |
290 | fail_alloc_txq: | |
291 | free_irq(mbox->irq, mbox); | |
292 | fail_request_irq: | |
340a614a HD |
293 | if (unlikely(mbox->ops->shutdown)) |
294 | mbox->ops->shutdown(mbox); | |
295 | ||
296 | return ret; | |
297 | } | |
298 | ||
299 | static void omap_mbox_fini(struct omap_mbox *mbox) | |
300 | { | |
301 | mbox_queue_free(mbox->txq); | |
302 | mbox_queue_free(mbox->rxq); | |
303 | ||
304 | free_irq(mbox->irq, mbox); | |
340a614a | 305 | |
5f00ec64 S |
306 | if (unlikely(mbox->ops->shutdown)) { |
307 | write_lock(&mboxes_lock); | |
308 | if (mbox_configured > 0) | |
309 | mbox_configured--; | |
310 | if (!mbox_configured) | |
311 | mbox->ops->shutdown(mbox); | |
312 | write_unlock(&mboxes_lock); | |
313 | } | |
340a614a HD |
314 | } |
315 | ||
316 | static struct omap_mbox **find_mboxes(const char *name) | |
317 | { | |
318 | struct omap_mbox **p; | |
319 | ||
320 | for (p = &mboxes; *p; p = &(*p)->next) { | |
321 | if (strcmp((*p)->name, name) == 0) | |
322 | break; | |
323 | } | |
324 | ||
325 | return p; | |
326 | } | |
327 | ||
328 | struct omap_mbox *omap_mbox_get(const char *name) | |
329 | { | |
330 | struct omap_mbox *mbox; | |
331 | int ret; | |
332 | ||
333 | read_lock(&mboxes_lock); | |
334 | mbox = *(find_mboxes(name)); | |
335 | if (mbox == NULL) { | |
336 | read_unlock(&mboxes_lock); | |
337 | return ERR_PTR(-ENOENT); | |
338 | } | |
339 | ||
340 | read_unlock(&mboxes_lock); | |
341 | ||
c7c158e5 | 342 | ret = omap_mbox_startup(mbox); |
340a614a HD |
343 | if (ret) |
344 | return ERR_PTR(-ENODEV); | |
345 | ||
346 | return mbox; | |
347 | } | |
348 | EXPORT_SYMBOL(omap_mbox_get); | |
349 | ||
350 | void omap_mbox_put(struct omap_mbox *mbox) | |
351 | { | |
352 | omap_mbox_fini(mbox); | |
353 | } | |
354 | EXPORT_SYMBOL(omap_mbox_put); | |
355 | ||
f48cca87 | 356 | int omap_mbox_register(struct device *parent, struct omap_mbox *mbox) |
340a614a HD |
357 | { |
358 | int ret = 0; | |
359 | struct omap_mbox **tmp; | |
360 | ||
361 | if (!mbox) | |
362 | return -EINVAL; | |
363 | if (mbox->next) | |
364 | return -EBUSY; | |
365 | ||
366 | write_lock(&mboxes_lock); | |
367 | tmp = find_mboxes(mbox->name); | |
f48cca87 | 368 | if (*tmp) { |
340a614a | 369 | ret = -EBUSY; |
f48cca87 HD |
370 | write_unlock(&mboxes_lock); |
371 | goto err_find; | |
372 | } | |
373 | *tmp = mbox; | |
340a614a HD |
374 | write_unlock(&mboxes_lock); |
375 | ||
f48cca87 HD |
376 | return 0; |
377 | ||
378 | err_find: | |
340a614a HD |
379 | return ret; |
380 | } | |
381 | EXPORT_SYMBOL(omap_mbox_register); | |
382 | ||
383 | int omap_mbox_unregister(struct omap_mbox *mbox) | |
384 | { | |
385 | struct omap_mbox **tmp; | |
386 | ||
387 | write_lock(&mboxes_lock); | |
388 | tmp = &mboxes; | |
389 | while (*tmp) { | |
390 | if (mbox == *tmp) { | |
391 | *tmp = mbox->next; | |
392 | mbox->next = NULL; | |
393 | write_unlock(&mboxes_lock); | |
394 | return 0; | |
395 | } | |
396 | tmp = &(*tmp)->next; | |
397 | } | |
398 | write_unlock(&mboxes_lock); | |
399 | ||
400 | return -EINVAL; | |
401 | } | |
402 | EXPORT_SYMBOL(omap_mbox_unregister); | |
403 | ||
c7c158e5 | 404 | static int __init omap_mbox_init(void) |
340a614a | 405 | { |
8250a5c3 RC |
406 | mboxd = create_workqueue("mboxd"); |
407 | if (!mboxd) | |
408 | return -ENOMEM; | |
409 | ||
c7c158e5 | 410 | return 0; |
340a614a | 411 | } |
c7c158e5 | 412 | module_init(omap_mbox_init); |
340a614a | 413 | |
c7c158e5 | 414 | static void __exit omap_mbox_exit(void) |
340a614a | 415 | { |
8250a5c3 | 416 | destroy_workqueue(mboxd); |
340a614a | 417 | } |
c7c158e5 | 418 | module_exit(omap_mbox_exit); |
340a614a | 419 | |
f48cca87 HD |
420 | MODULE_LICENSE("GPL v2"); |
421 | MODULE_DESCRIPTION("omap mailbox: interrupt driven messaging"); | |
422 | MODULE_AUTHOR("Toshihiro Kobayashi and Hiroshi DOYU"); |