4 * Copyright (C) 2006-2008 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/init.h>
25 #include <linux/module.h>
26 #include <linux/sched.h>
27 #include <linux/interrupt.h>
28 #include <linux/device.h>
29 #include <linux/blkdev.h>
30 #include <linux/err.h>
31 #include <linux/delay.h>
33 #include <mach/mailbox.h>
35 static int enable_seq_bit;
36 module_param(enable_seq_bit, bool, 0);
37 MODULE_PARM_DESC(enable_seq_bit, "Enable sequence bit checking.");
39 static struct omap_mbox *mboxes;
40 static DEFINE_RWLOCK(mboxes_lock);
43 * Mailbox sequence bit API
46 /* seq_rcv should be initialized with any value other than
47 * 0 and 1 << 31, to allow either value for the first
49 static inline void mbox_seq_init(struct omap_mbox *mbox)
54 /* any value other than 0 and 1 << 31 */
55 mbox->seq_rcv = 0xffffffff;
58 static inline void mbox_seq_toggle(struct omap_mbox *mbox, mbox_msg_t * msg)
63 /* add seq_snd to msg */
64 *msg = (*msg & 0x7fffffff) | mbox->seq_snd;
66 mbox->seq_snd ^= 1 << 31;
69 static inline int mbox_seq_test(struct omap_mbox *mbox, mbox_msg_t msg)
76 seq = msg & (1 << 31);
77 if (seq == mbox->seq_rcv)
83 /* Mailbox FIFO handle functions */
84 static inline mbox_msg_t mbox_fifo_read(struct omap_mbox *mbox)
86 return mbox->ops->fifo_read(mbox);
88 static inline void mbox_fifo_write(struct omap_mbox *mbox, mbox_msg_t msg)
90 mbox->ops->fifo_write(mbox, msg);
92 static inline int mbox_fifo_empty(struct omap_mbox *mbox)
94 return mbox->ops->fifo_empty(mbox);
96 static inline int mbox_fifo_full(struct omap_mbox *mbox)
98 return mbox->ops->fifo_full(mbox);
101 /* Mailbox IRQ handle functions */
102 static inline void enable_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
104 mbox->ops->enable_irq(mbox, irq);
106 static inline void disable_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
108 mbox->ops->disable_irq(mbox, irq);
110 static inline void ack_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
112 if (mbox->ops->ack_irq)
113 mbox->ops->ack_irq(mbox, irq);
115 static inline int is_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
117 return mbox->ops->is_irq(mbox, irq);
120 /* Mailbox Sequence Bit function */
121 void omap_mbox_init_seq(struct omap_mbox *mbox)
125 EXPORT_SYMBOL(omap_mbox_init_seq);
130 static int __mbox_msg_send(struct omap_mbox *mbox, mbox_msg_t msg, void *arg)
132 int ret = 0, i = 1000;
134 while (mbox_fifo_full(mbox)) {
135 if (mbox->ops->type == OMAP_MBOX_TYPE2)
142 if (arg && mbox->txq->callback) {
143 ret = mbox->txq->callback(arg);
148 mbox_seq_toggle(mbox, &msg);
149 mbox_fifo_write(mbox, msg);
154 int omap_mbox_msg_send(struct omap_mbox *mbox, mbox_msg_t msg, void* arg)
157 struct request_queue *q = mbox->txq->queue;
160 rq = blk_get_request(q, WRITE, GFP_ATOMIC);
166 rq->data = (void *)msg;
167 blk_insert_request(q, rq, 0, arg);
169 schedule_work(&mbox->txq->work);
173 EXPORT_SYMBOL(omap_mbox_msg_send);
175 static void mbox_tx_work(struct work_struct *work)
179 struct omap_mbox_queue *mq = container_of(work,
180 struct omap_mbox_queue, work);
181 struct omap_mbox *mbox = mq->queue->queuedata;
182 struct request_queue *q = mbox->txq->queue;
185 spin_lock(q->queue_lock);
186 rq = elv_next_request(q);
187 spin_unlock(q->queue_lock);
192 ret = __mbox_msg_send(mbox, (mbox_msg_t) rq->data, rq->special);
194 enable_mbox_irq(mbox, IRQ_TX);
198 spin_lock(q->queue_lock);
199 if (__blk_end_request(rq, 0, 0))
201 spin_unlock(q->queue_lock);
206 * Message receiver(workqueue)
208 static void mbox_rx_work(struct work_struct *work)
210 struct omap_mbox_queue *mq =
211 container_of(work, struct omap_mbox_queue, work);
212 struct omap_mbox *mbox = mq->queue->queuedata;
213 struct request_queue *q = mbox->rxq->queue;
218 if (mbox->rxq->callback == NULL) {
219 sysfs_notify(&mbox->dev->kobj, NULL, "mbox");
224 spin_lock_irqsave(q->queue_lock, flags);
225 rq = elv_next_request(q);
226 spin_unlock_irqrestore(q->queue_lock, flags);
230 msg = (mbox_msg_t) rq->data;
232 if (blk_end_request(rq, 0, 0))
235 mbox->rxq->callback((void *)msg);
240 * Mailbox interrupt handler
242 static void mbox_txq_fn(struct request_queue * q)
246 static void mbox_rxq_fn(struct request_queue * q)
250 static void __mbox_tx_interrupt(struct omap_mbox *mbox)
252 disable_mbox_irq(mbox, IRQ_TX);
253 ack_mbox_irq(mbox, IRQ_TX);
254 schedule_work(&mbox->txq->work);
257 static void __mbox_rx_interrupt(struct omap_mbox *mbox)
261 struct request_queue *q = mbox->rxq->queue;
263 disable_mbox_irq(mbox, IRQ_RX);
265 while (!mbox_fifo_empty(mbox)) {
266 rq = blk_get_request(q, WRITE, GFP_ATOMIC);
270 msg = mbox_fifo_read(mbox);
271 rq->data = (void *)msg;
273 if (unlikely(mbox_seq_test(mbox, msg))) {
274 pr_info("mbox: Illegal seq bit!(%08x)\n", msg);
275 if (mbox->err_notify)
279 blk_insert_request(q, rq, 0, NULL);
280 if (mbox->ops->type == OMAP_MBOX_TYPE1)
284 /* no more messages in the fifo. clear IRQ source. */
285 ack_mbox_irq(mbox, IRQ_RX);
286 enable_mbox_irq(mbox, IRQ_RX);
288 schedule_work(&mbox->rxq->work);
291 static irqreturn_t mbox_interrupt(int irq, void *p)
293 struct omap_mbox *mbox = p;
295 if (is_mbox_irq(mbox, IRQ_TX))
296 __mbox_tx_interrupt(mbox);
298 if (is_mbox_irq(mbox, IRQ_RX))
299 __mbox_rx_interrupt(mbox);
308 omap_mbox_write(struct device *dev, struct device_attribute *attr,
309 const char * buf, size_t count)
312 mbox_msg_t *p = (mbox_msg_t *)buf;
313 struct omap_mbox *mbox = dev_get_drvdata(dev);
315 for (; count >= sizeof(mbox_msg_t); count -= sizeof(mbox_msg_t)) {
316 ret = omap_mbox_msg_send(mbox, be32_to_cpu(*p), NULL);
322 return (size_t)((char *)p - buf);
326 omap_mbox_read(struct device *dev, struct device_attribute *attr, char *buf)
330 mbox_msg_t *p = (mbox_msg_t *) buf;
331 struct omap_mbox *mbox = dev_get_drvdata(dev);
332 struct request_queue *q = mbox->rxq->queue;
335 spin_lock_irqsave(q->queue_lock, flags);
336 rq = elv_next_request(q);
337 spin_unlock_irqrestore(q->queue_lock, flags);
342 *p = (mbox_msg_t) rq->data;
344 if (blk_end_request(rq, 0, 0))
347 if (unlikely(mbox_seq_test(mbox, *p))) {
348 pr_info("mbox: Illegal seq bit!(%08x) ignored\n", *p);
354 pr_debug("%02x %02x %02x %02x\n", buf[0], buf[1], buf[2], buf[3]);
356 return (size_t) ((char *)p - buf);
359 static DEVICE_ATTR(mbox, S_IRUGO | S_IWUSR, omap_mbox_read, omap_mbox_write);
361 static ssize_t mbox_show(struct class *class, char *buf)
363 return sprintf(buf, "mbox");
366 static CLASS_ATTR(mbox, S_IRUGO, mbox_show, NULL);
368 static struct class omap_mbox_class = {
369 .name = "omap-mailbox",
372 static struct omap_mbox_queue *mbox_queue_alloc(struct omap_mbox *mbox,
373 request_fn_proc * proc,
374 void (*work) (struct work_struct *))
376 struct request_queue *q;
377 struct omap_mbox_queue *mq;
379 mq = kzalloc(sizeof(struct omap_mbox_queue), GFP_KERNEL);
383 spin_lock_init(&mq->lock);
385 q = blk_init_queue(proc, &mq->lock);
391 INIT_WORK(&mq->work, work);
399 static void mbox_queue_free(struct omap_mbox_queue *q)
401 blk_cleanup_queue(q->queue);
405 static int omap_mbox_init(struct omap_mbox *mbox)
408 struct omap_mbox_queue *mq;
410 if (likely(mbox->ops->startup)) {
411 ret = mbox->ops->startup(mbox);
416 ret = request_irq(mbox->irq, mbox_interrupt, IRQF_DISABLED,
420 "failed to register mailbox interrupt:%d\n", ret);
421 goto fail_request_irq;
424 mq = mbox_queue_alloc(mbox, mbox_txq_fn, mbox_tx_work);
431 mq = mbox_queue_alloc(mbox, mbox_rxq_fn, mbox_rx_work);
441 mbox_queue_free(mbox->txq);
443 free_irq(mbox->irq, mbox);
445 if (unlikely(mbox->ops->shutdown))
446 mbox->ops->shutdown(mbox);
451 static void omap_mbox_fini(struct omap_mbox *mbox)
453 mbox_queue_free(mbox->txq);
454 mbox_queue_free(mbox->rxq);
456 free_irq(mbox->irq, mbox);
458 if (unlikely(mbox->ops->shutdown))
459 mbox->ops->shutdown(mbox);
462 static struct omap_mbox **find_mboxes(const char *name)
464 struct omap_mbox **p;
466 for (p = &mboxes; *p; p = &(*p)->next) {
467 if (strcmp((*p)->name, name) == 0)
474 struct omap_mbox *omap_mbox_get(const char *name)
476 struct omap_mbox *mbox;
479 read_lock(&mboxes_lock);
480 mbox = *(find_mboxes(name));
482 read_unlock(&mboxes_lock);
483 return ERR_PTR(-ENOENT);
486 read_unlock(&mboxes_lock);
488 ret = omap_mbox_init(mbox);
490 return ERR_PTR(-ENODEV);
494 EXPORT_SYMBOL(omap_mbox_get);
496 void omap_mbox_put(struct omap_mbox *mbox)
498 omap_mbox_fini(mbox);
500 EXPORT_SYMBOL(omap_mbox_put);
502 int omap_mbox_register(struct device *parent, struct omap_mbox *mbox)
505 struct omap_mbox **tmp;
512 mbox->dev = device_create(&omap_mbox_class,
513 parent, 0, mbox, "%s", mbox->name);
514 if (IS_ERR(mbox->dev))
515 return PTR_ERR(mbox->dev);
517 ret = device_create_file(mbox->dev, &dev_attr_mbox);
521 write_lock(&mboxes_lock);
522 tmp = find_mboxes(mbox->name);
525 write_unlock(&mboxes_lock);
529 write_unlock(&mboxes_lock);
534 device_remove_file(mbox->dev, &dev_attr_mbox);
536 device_unregister(mbox->dev);
539 EXPORT_SYMBOL(omap_mbox_register);
541 int omap_mbox_unregister(struct omap_mbox *mbox)
543 struct omap_mbox **tmp;
545 write_lock(&mboxes_lock);
551 write_unlock(&mboxes_lock);
552 device_remove_file(mbox->dev, &dev_attr_mbox);
553 device_unregister(mbox->dev);
558 write_unlock(&mboxes_lock);
562 EXPORT_SYMBOL(omap_mbox_unregister);
564 static int __init omap_mbox_class_init(void)
566 int ret = class_register(&omap_mbox_class);
568 ret = class_create_file(&omap_mbox_class, &class_attr_mbox);
573 static void __exit omap_mbox_class_exit(void)
575 class_remove_file(&omap_mbox_class, &class_attr_mbox);
576 class_unregister(&omap_mbox_class);
579 subsys_initcall(omap_mbox_class_init);
580 module_exit(omap_mbox_class_exit);
582 MODULE_LICENSE("GPL v2");
583 MODULE_DESCRIPTION("omap mailbox: interrupt driven messaging");
584 MODULE_AUTHOR("Toshihiro Kobayashi and Hiroshi DOYU");