[linux-2.6-block.git] / arch / arm / plat-omap / mailbox.c

/*
 * OMAP mailbox driver
 *
 * Copyright (C) 2006-2009 Nokia Corporation. All rights reserved.
 *
 * Contact: Hiroshi DOYU <Hiroshi.DOYU@nokia.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 *
 */

#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/device.h>
#include <linux/delay.h>

#include <plat/mailbox.h>

static struct omap_mbox *mboxes;
static DEFINE_RWLOCK(mboxes_lock);

static int mbox_configured;

/* Mailbox FIFO handle functions */
static inline mbox_msg_t mbox_fifo_read(struct omap_mbox *mbox)
{
	return mbox->ops->fifo_read(mbox);
}
static inline void mbox_fifo_write(struct omap_mbox *mbox, mbox_msg_t msg)
{
	mbox->ops->fifo_write(mbox, msg);
}
static inline int mbox_fifo_empty(struct omap_mbox *mbox)
{
	return mbox->ops->fifo_empty(mbox);
}
static inline int mbox_fifo_full(struct omap_mbox *mbox)
{
	return mbox->ops->fifo_full(mbox);
}

/* Mailbox IRQ handle functions */
static inline void ack_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
{
	if (mbox->ops->ack_irq)
		mbox->ops->ack_irq(mbox, irq);
}
static inline int is_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
{
	return mbox->ops->is_irq(mbox, irq);
}

/*
 * message sender
 */
static int __mbox_msg_send(struct omap_mbox *mbox, mbox_msg_t msg)
{
	int ret = 0, i = 1000;

	while (mbox_fifo_full(mbox)) {
		if (mbox->ops->type == OMAP_MBOX_TYPE2)
			return -1;
		if (--i == 0)
			return -1;
		udelay(1);
	}
	mbox_fifo_write(mbox, msg);
	return ret;
}


int omap_mbox_msg_send(struct omap_mbox *mbox, mbox_msg_t msg)
{

	struct request *rq;
	struct request_queue *q = mbox->txq->queue;

	rq = blk_get_request(q, WRITE, GFP_ATOMIC);
	if (unlikely(!rq))
		return -ENOMEM;

	blk_insert_request(q, rq, 0, (void *) msg);
	tasklet_schedule(&mbox->txq->tasklet);

	return 0;
}
EXPORT_SYMBOL(omap_mbox_msg_send);

static void mbox_tx_tasklet(unsigned long tx_data)
{
	int ret;
	struct request *rq;
	struct omap_mbox *mbox = (struct omap_mbox *)tx_data;
	struct request_queue *q = mbox->txq->queue;

	while (1) {

		rq = blk_fetch_request(q);

		if (!rq)
			break;

		ret = __mbox_msg_send(mbox, (mbox_msg_t)rq->special);
		if (ret) {
			omap_mbox_enable_irq(mbox, IRQ_TX);
			blk_requeue_request(q, rq);
			return;
		}
		blk_end_request_all(rq, 0);
	}
}

/*
 * Message receiver(workqueue)
 */
static void mbox_rx_work(struct work_struct *work)
{
	struct omap_mbox_queue *mq =
			container_of(work, struct omap_mbox_queue, work);
	struct omap_mbox *mbox = mq->queue->queuedata;
	struct request_queue *q = mbox->rxq->queue;
	struct request *rq;
	mbox_msg_t msg;
	unsigned long flags;

	while (1) {
		spin_lock_irqsave(q->queue_lock, flags);
		rq = blk_fetch_request(q);
		spin_unlock_irqrestore(q->queue_lock, flags);
		if (!rq)
			break;

		msg = (mbox_msg_t)rq->special;
		blk_end_request_all(rq, 0);
		mbox->rxq->callback((void *)msg);
	}
}

/*
 * Mailbox interrupt handler
 */
static void mbox_txq_fn(struct request_queue *q)
{
}

static void mbox_rxq_fn(struct request_queue *q)
{
}

static void __mbox_tx_interrupt(struct omap_mbox *mbox)
{
	omap_mbox_disable_irq(mbox, IRQ_TX);
	ack_mbox_irq(mbox, IRQ_TX);
	tasklet_schedule(&mbox->txq->tasklet);
}

static void __mbox_rx_interrupt(struct omap_mbox *mbox)
{
	struct request *rq;
	mbox_msg_t msg;
	struct request_queue *q = mbox->rxq->queue;

	while (!mbox_fifo_empty(mbox)) {
		rq = blk_get_request(q, WRITE, GFP_ATOMIC);
		if (unlikely(!rq))
			goto nomem;

		msg = mbox_fifo_read(mbox);


		blk_insert_request(q, rq, 0, (void *)msg);
		if (mbox->ops->type == OMAP_MBOX_TYPE1)
			break;
	}

	/* no more messages in the fifo. clear IRQ source. */
	ack_mbox_irq(mbox, IRQ_RX);
nomem:
	schedule_work(&mbox->rxq->work);
}

static irqreturn_t mbox_interrupt(int irq, void *p)
{
	struct omap_mbox *mbox = p;

	if (is_mbox_irq(mbox, IRQ_TX))
		__mbox_tx_interrupt(mbox);

	if (is_mbox_irq(mbox, IRQ_RX))
		__mbox_rx_interrupt(mbox);

	return IRQ_HANDLED;
}

static struct omap_mbox_queue *mbox_queue_alloc(struct omap_mbox *mbox,
					request_fn_proc *proc,
					void (*work) (struct work_struct *),
					void (*tasklet)(unsigned long))
{
	struct request_queue *q;
	struct omap_mbox_queue *mq;

	mq = kzalloc(sizeof(struct omap_mbox_queue), GFP_KERNEL);
	if (!mq)
		return NULL;

	spin_lock_init(&mq->lock);

	q = blk_init_queue(proc, &mq->lock);
	if (!q)
		goto error;
	q->queuedata = mbox;
	mq->queue = q;

	if (work)
		INIT_WORK(&mq->work, work);

	if (tasklet)
		tasklet_init(&mq->tasklet, tasklet, (unsigned long)mbox);
	return mq;
error:
	kfree(mq);
	return NULL;
}

static void mbox_queue_free(struct omap_mbox_queue *q)
{
	blk_cleanup_queue(q->queue);
	kfree(q);
}

static int omap_mbox_startup(struct omap_mbox *mbox)
{
	int ret = 0;
	struct omap_mbox_queue *mq;

	if (likely(mbox->ops->startup)) {
		write_lock(&mboxes_lock);
		if (!mbox_configured)
			ret = mbox->ops->startup(mbox);

		if (unlikely(ret)) {
			write_unlock(&mboxes_lock);
			return ret;
		}
		mbox_configured++;
		write_unlock(&mboxes_lock);
	}

	ret = request_irq(mbox->irq, mbox_interrupt, IRQF_SHARED,
				mbox->name, mbox);
	if (unlikely(ret)) {
		printk(KERN_ERR
			"failed to register mailbox interrupt:%d\n", ret);
		goto fail_request_irq;
	}

	mq = mbox_queue_alloc(mbox, mbox_txq_fn, NULL, mbox_tx_tasklet);
	if (!mq) {
		ret = -ENOMEM;
		goto fail_alloc_txq;
	}
	mbox->txq = mq;

	mq = mbox_queue_alloc(mbox, mbox_rxq_fn, mbox_rx_work, NULL);
	if (!mq) {
		ret = -ENOMEM;
		goto fail_alloc_rxq;
	}
	mbox->rxq = mq;

	return 0;

 fail_alloc_rxq:
	mbox_queue_free(mbox->txq);
 fail_alloc_txq:
	free_irq(mbox->irq, mbox);
 fail_request_irq:
	if (unlikely(mbox->ops->shutdown))
		mbox->ops->shutdown(mbox);

	return ret;
}

static void omap_mbox_fini(struct omap_mbox *mbox)
{
	mbox_queue_free(mbox->txq);
	mbox_queue_free(mbox->rxq);

	free_irq(mbox->irq, mbox);

	if (unlikely(mbox->ops->shutdown)) {
		write_lock(&mboxes_lock);
		if (mbox_configured > 0)
			mbox_configured--;
		if (!mbox_configured)
			mbox->ops->shutdown(mbox);
		write_unlock(&mboxes_lock);
	}
}

static struct omap_mbox **find_mboxes(const char *name)
{
	struct omap_mbox **p;

	for (p = &mboxes; *p; p = &(*p)->next) {
		if (strcmp((*p)->name, name) == 0)
			break;
	}

	return p;
}

struct omap_mbox *omap_mbox_get(const char *name)
{
	struct omap_mbox *mbox;
	int ret;

	read_lock(&mboxes_lock);
	mbox = *(find_mboxes(name));
	if (mbox == NULL) {
		read_unlock(&mboxes_lock);
		return ERR_PTR(-ENOENT);
	}

	read_unlock(&mboxes_lock);

	ret = omap_mbox_startup(mbox);
	if (ret)
		return ERR_PTR(-ENODEV);

	return mbox;
}
EXPORT_SYMBOL(omap_mbox_get);

void omap_mbox_put(struct omap_mbox *mbox)
{
	omap_mbox_fini(mbox);
}
EXPORT_SYMBOL(omap_mbox_put);

int omap_mbox_register(struct device *parent, struct omap_mbox *mbox)
{
	int ret = 0;
	struct omap_mbox **tmp;

	if (!mbox)
		return -EINVAL;
	if (mbox->next)
		return -EBUSY;

	write_lock(&mboxes_lock);
	tmp = find_mboxes(mbox->name);
	if (*tmp) {
		ret = -EBUSY;
		write_unlock(&mboxes_lock);
		goto err_find;
	}
	*tmp = mbox;
	write_unlock(&mboxes_lock);

	return 0;

err_find:
	return ret;
}
EXPORT_SYMBOL(omap_mbox_register);

int omap_mbox_unregister(struct omap_mbox *mbox)
{
	struct omap_mbox **tmp;

	write_lock(&mboxes_lock);
	tmp = &mboxes;
	while (*tmp) {
		if (mbox == *tmp) {
			*tmp = mbox->next;
			mbox->next = NULL;
			write_unlock(&mboxes_lock);
			return 0;
		}
		tmp = &(*tmp)->next;
	}
	write_unlock(&mboxes_lock);

	return -EINVAL;
}
EXPORT_SYMBOL(omap_mbox_unregister);

static int __init omap_mbox_init(void)
{
	return 0;
}
module_init(omap_mbox_init);

static void __exit omap_mbox_exit(void)
{
}
module_exit(omap_mbox_exit);

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