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