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git.proxmox.com Git - mirror_ubuntu-zesty-kernel.git/blob - arch/arm/plat-omap/mailbox.c
4 * Copyright (C) 2006-2009 Nokia Corporation. All rights reserved.
6 * Contact: Hiroshi DOYU <Hiroshi.DOYU@nokia.com>
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.
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.
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
24 #include <linux/module.h>
25 #include <linux/interrupt.h>
26 #include <linux/device.h>
27 #include <linux/delay.h>
29 #include <plat/mailbox.h>
31 static struct workqueue_struct
*mboxd
;
32 static struct omap_mbox
*mboxes
;
33 static DEFINE_RWLOCK(mboxes_lock
);
35 static int mbox_configured
;
37 /* Mailbox FIFO handle functions */
38 static inline mbox_msg_t
mbox_fifo_read(struct omap_mbox
*mbox
)
40 return mbox
->ops
->fifo_read(mbox
);
42 static inline void mbox_fifo_write(struct omap_mbox
*mbox
, mbox_msg_t msg
)
44 mbox
->ops
->fifo_write(mbox
, msg
);
46 static inline int mbox_fifo_empty(struct omap_mbox
*mbox
)
48 return mbox
->ops
->fifo_empty(mbox
);
50 static inline int mbox_fifo_full(struct omap_mbox
*mbox
)
52 return mbox
->ops
->fifo_full(mbox
);
55 /* Mailbox IRQ handle functions */
56 static inline void ack_mbox_irq(struct omap_mbox
*mbox
, omap_mbox_irq_t irq
)
58 if (mbox
->ops
->ack_irq
)
59 mbox
->ops
->ack_irq(mbox
, irq
);
61 static inline int is_mbox_irq(struct omap_mbox
*mbox
, omap_mbox_irq_t irq
)
63 return mbox
->ops
->is_irq(mbox
, irq
);
69 static int __mbox_msg_send(struct omap_mbox
*mbox
, mbox_msg_t msg
)
71 int ret
= 0, i
= 1000;
73 while (mbox_fifo_full(mbox
)) {
74 if (mbox
->ops
->type
== OMAP_MBOX_TYPE2
)
80 mbox_fifo_write(mbox
, msg
);
85 int omap_mbox_msg_send(struct omap_mbox
*mbox
, mbox_msg_t msg
)
89 struct request_queue
*q
= mbox
->txq
->queue
;
91 rq
= blk_get_request(q
, WRITE
, GFP_ATOMIC
);
95 blk_insert_request(q
, rq
, 0, (void *) msg
);
96 tasklet_schedule(&mbox
->txq
->tasklet
);
100 EXPORT_SYMBOL(omap_mbox_msg_send
);
102 static void mbox_tx_tasklet(unsigned long tx_data
)
106 struct omap_mbox
*mbox
= (struct omap_mbox
*)tx_data
;
107 struct request_queue
*q
= mbox
->txq
->queue
;
111 rq
= blk_fetch_request(q
);
116 ret
= __mbox_msg_send(mbox
, (mbox_msg_t
)rq
->special
);
118 omap_mbox_enable_irq(mbox
, IRQ_TX
);
119 blk_requeue_request(q
, rq
);
122 blk_end_request_all(rq
, 0);
127 * Message receiver(workqueue)
129 static void mbox_rx_work(struct work_struct
*work
)
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
;
140 spin_lock_irqsave(q
->queue_lock
, flags
);
141 rq
= blk_fetch_request(q
);
142 spin_unlock_irqrestore(q
->queue_lock
, flags
);
146 msg
= (mbox_msg_t
)rq
->special
;
147 blk_end_request_all(rq
, 0);
148 mbox
->rxq
->callback((void *)msg
);
153 * Mailbox interrupt handler
155 static void mbox_txq_fn(struct request_queue
*q
)
159 static void mbox_rxq_fn(struct request_queue
*q
)
163 static void __mbox_tx_interrupt(struct omap_mbox
*mbox
)
165 omap_mbox_disable_irq(mbox
, IRQ_TX
);
166 ack_mbox_irq(mbox
, IRQ_TX
);
167 tasklet_schedule(&mbox
->txq
->tasklet
);
170 static void __mbox_rx_interrupt(struct omap_mbox
*mbox
)
174 struct request_queue
*q
= mbox
->rxq
->queue
;
176 while (!mbox_fifo_empty(mbox
)) {
177 rq
= blk_get_request(q
, WRITE
, GFP_ATOMIC
);
181 msg
= mbox_fifo_read(mbox
);
184 blk_insert_request(q
, rq
, 0, (void *)msg
);
185 if (mbox
->ops
->type
== OMAP_MBOX_TYPE1
)
189 /* no more messages in the fifo. clear IRQ source. */
190 ack_mbox_irq(mbox
, IRQ_RX
);
192 queue_work(mboxd
, &mbox
->rxq
->work
);
195 static irqreturn_t
mbox_interrupt(int irq
, void *p
)
197 struct omap_mbox
*mbox
= p
;
199 if (is_mbox_irq(mbox
, IRQ_TX
))
200 __mbox_tx_interrupt(mbox
);
202 if (is_mbox_irq(mbox
, IRQ_RX
))
203 __mbox_rx_interrupt(mbox
);
208 static struct omap_mbox_queue
*mbox_queue_alloc(struct omap_mbox
*mbox
,
209 request_fn_proc
*proc
,
210 void (*work
) (struct work_struct
*),
211 void (*tasklet
)(unsigned long))
213 struct request_queue
*q
;
214 struct omap_mbox_queue
*mq
;
216 mq
= kzalloc(sizeof(struct omap_mbox_queue
), GFP_KERNEL
);
220 spin_lock_init(&mq
->lock
);
222 q
= blk_init_queue(proc
, &mq
->lock
);
229 INIT_WORK(&mq
->work
, work
);
232 tasklet_init(&mq
->tasklet
, tasklet
, (unsigned long)mbox
);
239 static void mbox_queue_free(struct omap_mbox_queue
*q
)
241 blk_cleanup_queue(q
->queue
);
245 static int omap_mbox_startup(struct omap_mbox
*mbox
)
248 struct omap_mbox_queue
*mq
;
250 if (likely(mbox
->ops
->startup
)) {
251 write_lock(&mboxes_lock
);
252 if (!mbox_configured
)
253 ret
= mbox
->ops
->startup(mbox
);
256 write_unlock(&mboxes_lock
);
260 write_unlock(&mboxes_lock
);
263 ret
= request_irq(mbox
->irq
, mbox_interrupt
, IRQF_SHARED
,
267 "failed to register mailbox interrupt:%d\n", ret
);
268 goto fail_request_irq
;
271 mq
= mbox_queue_alloc(mbox
, mbox_txq_fn
, NULL
, mbox_tx_tasklet
);
278 mq
= mbox_queue_alloc(mbox
, mbox_rxq_fn
, mbox_rx_work
, NULL
);
288 mbox_queue_free(mbox
->txq
);
290 free_irq(mbox
->irq
, mbox
);
292 if (unlikely(mbox
->ops
->shutdown
))
293 mbox
->ops
->shutdown(mbox
);
298 static void omap_mbox_fini(struct omap_mbox
*mbox
)
300 mbox_queue_free(mbox
->txq
);
301 mbox_queue_free(mbox
->rxq
);
303 free_irq(mbox
->irq
, mbox
);
305 if (unlikely(mbox
->ops
->shutdown
)) {
306 write_lock(&mboxes_lock
);
307 if (mbox_configured
> 0)
309 if (!mbox_configured
)
310 mbox
->ops
->shutdown(mbox
);
311 write_unlock(&mboxes_lock
);
315 static struct omap_mbox
**find_mboxes(const char *name
)
317 struct omap_mbox
**p
;
319 for (p
= &mboxes
; *p
; p
= &(*p
)->next
) {
320 if (strcmp((*p
)->name
, name
) == 0)
327 struct omap_mbox
*omap_mbox_get(const char *name
)
329 struct omap_mbox
*mbox
;
332 read_lock(&mboxes_lock
);
333 mbox
= *(find_mboxes(name
));
335 read_unlock(&mboxes_lock
);
336 return ERR_PTR(-ENOENT
);
339 read_unlock(&mboxes_lock
);
341 ret
= omap_mbox_startup(mbox
);
343 return ERR_PTR(-ENODEV
);
347 EXPORT_SYMBOL(omap_mbox_get
);
349 void omap_mbox_put(struct omap_mbox
*mbox
)
351 omap_mbox_fini(mbox
);
353 EXPORT_SYMBOL(omap_mbox_put
);
355 int omap_mbox_register(struct device
*parent
, struct omap_mbox
*mbox
)
358 struct omap_mbox
**tmp
;
365 write_lock(&mboxes_lock
);
366 tmp
= find_mboxes(mbox
->name
);
369 write_unlock(&mboxes_lock
);
373 write_unlock(&mboxes_lock
);
380 EXPORT_SYMBOL(omap_mbox_register
);
382 int omap_mbox_unregister(struct omap_mbox
*mbox
)
384 struct omap_mbox
**tmp
;
386 write_lock(&mboxes_lock
);
392 write_unlock(&mboxes_lock
);
397 write_unlock(&mboxes_lock
);
401 EXPORT_SYMBOL(omap_mbox_unregister
);
403 static int __init
omap_mbox_init(void)
405 mboxd
= create_workqueue("mboxd");
411 module_init(omap_mbox_init
);
413 static void __exit
omap_mbox_exit(void)
415 destroy_workqueue(mboxd
);
417 module_exit(omap_mbox_exit
);
419 MODULE_LICENSE("GPL v2");
420 MODULE_DESCRIPTION("omap mailbox: interrupt driven messaging");
421 MODULE_AUTHOR("Toshihiro Kobayashi and Hiroshi DOYU");