[mirror_ubuntu-jammy-kernel.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/interrupt.h>
#include <linux/spinlock.h>
#include <linux/mutex.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/kfifo.h>
#include <linux/err.h>
#include <linux/notifier.h>

#include <plat/mailbox.h>

static struct omap_mbox **mboxes;

static int mbox_configured;
static DEFINE_MUTEX(mbox_configured_lock);

static unsigned int mbox_kfifo_size = CONFIG_OMAP_MBOX_KFIFO_SIZE;
module_param(mbox_kfifo_size, uint, S_IRUGO);
MODULE_PARM_DESC(mbox_kfifo_size, "Size of omap's mailbox kfifo (bytes)");

/* 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_poll_for_space(struct omap_mbox *mbox)
{
	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);
	}
	return ret;
}

int omap_mbox_msg_send(struct omap_mbox *mbox, mbox_msg_t msg)
{
	struct omap_mbox_queue *mq = mbox->txq;
	int ret = 0, len;

	spin_lock_bh(&mq->lock);

	if (kfifo_avail(&mq->fifo) < sizeof(msg)) {
		ret = -ENOMEM;
		goto out;
	}

	if (kfifo_is_empty(&mq->fifo) && !__mbox_poll_for_space(mbox)) {
		mbox_fifo_write(mbox, msg);
		goto out;
	}

	len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
	WARN_ON(len != sizeof(msg));

	tasklet_schedule(&mbox->txq->tasklet);

out:
	spin_unlock_bh(&mq->lock);
	return ret;
}
EXPORT_SYMBOL(omap_mbox_msg_send);

static void mbox_tx_tasklet(unsigned long tx_data)
{
	struct omap_mbox *mbox = (struct omap_mbox *)tx_data;
	struct omap_mbox_queue *mq = mbox->txq;
	mbox_msg_t msg;
	int ret;

	while (kfifo_len(&mq->fifo)) {
		if (__mbox_poll_for_space(mbox)) {
			omap_mbox_enable_irq(mbox, IRQ_TX);
			break;
		}

		ret = kfifo_out(&mq->fifo, (unsigned char *)&msg,
								sizeof(msg));
		WARN_ON(ret != sizeof(msg));

		mbox_fifo_write(mbox, msg);
	}
}

/*
 * 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);
	mbox_msg_t msg;
	int len;

	while (kfifo_len(&mq->fifo) >= sizeof(msg)) {
		len = kfifo_out(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
		WARN_ON(len != sizeof(msg));

		blocking_notifier_call_chain(&mq->mbox->notifier, len,
								(void *)msg);
		spin_lock_irq(&mq->lock);
		if (mq->full) {
			mq->full = false;
			omap_mbox_enable_irq(mq->mbox, IRQ_RX);
		}
		spin_unlock_irq(&mq->lock);
	}
}

/*
 * Mailbox interrupt handler
 */
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 omap_mbox_queue *mq = mbox->rxq;
	mbox_msg_t msg;
	int len;

	while (!mbox_fifo_empty(mbox)) {
		if (unlikely(kfifo_avail(&mq->fifo) < sizeof(msg))) {
			omap_mbox_disable_irq(mbox, IRQ_RX);
			mq->full = true;
			goto nomem;
		}

		msg = mbox_fifo_read(mbox);

		len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
		WARN_ON(len != sizeof(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,
					void (*work) (struct work_struct *),
					void (*tasklet)(unsigned long))
{
	struct omap_mbox_queue *mq;

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

	spin_lock_init(&mq->lock);

	if (kfifo_alloc(&mq->fifo, mbox_kfifo_size, GFP_KERNEL))
		goto error;

	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)
{
	kfifo_free(&q->fifo);
	kfree(q);
}

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

	mutex_lock(&mbox_configured_lock);
	if (!mbox_configured++) {
		if (likely(mbox->ops->startup)) {
			ret = mbox->ops->startup(mbox);
			if (unlikely(ret))
				goto fail_startup;
		} else
			goto fail_startup;
	}

	if (!mbox->use_count++) {
		ret = request_irq(mbox->irq, mbox_interrupt, IRQF_SHARED,
							mbox->name, mbox);
		if (unlikely(ret)) {
			pr_err("failed to register mailbox interrupt:%d\n",
									ret);
			goto fail_request_irq;
		}
		mq = mbox_queue_alloc(mbox, NULL, mbox_tx_tasklet);
		if (!mq) {
			ret = -ENOMEM;
			goto fail_alloc_txq;
		}
		mbox->txq = mq;

		mq = mbox_queue_alloc(mbox, mbox_rx_work, NULL);
		if (!mq) {
			ret = -ENOMEM;
			goto fail_alloc_rxq;
		}
		mbox->rxq = mq;
		mq->mbox = mbox;
	}
	mutex_unlock(&mbox_configured_lock);
	return 0;

fail_alloc_rxq:
	mbox_queue_free(mbox->txq);
fail_alloc_txq:
	free_irq(mbox->irq, mbox);
fail_request_irq:
	if (mbox->ops->shutdown)
		mbox->ops->shutdown(mbox);
	mbox->use_count--;
fail_startup:
	mbox_configured--;
	mutex_unlock(&mbox_configured_lock);
	return ret;
}

static void omap_mbox_fini(struct omap_mbox *mbox)
{
	mutex_lock(&mbox_configured_lock);

	if (!--mbox->use_count) {
		free_irq(mbox->irq, mbox);
		tasklet_kill(&mbox->txq->tasklet);
	flush_work_sync(&mbox->rxq->work);
		mbox_queue_free(mbox->txq);
		mbox_queue_free(mbox->rxq);
	}

	if (likely(mbox->ops->shutdown)) {
		if (!--mbox_configured)
			mbox->ops->shutdown(mbox);
	}

	mutex_unlock(&mbox_configured_lock);
}

struct omap_mbox *omap_mbox_get(const char *name, struct notifier_block *nb)
{
	struct omap_mbox *_mbox, *mbox = NULL;
	int i, ret;

	if (!mboxes)
		return ERR_PTR(-EINVAL);

	for (i = 0; (_mbox = mboxes[i]); i++) {
		if (!strcmp(_mbox->name, name)) {
			mbox = _mbox;
			break;
		}
	}

	if (!mbox)
		return ERR_PTR(-ENOENT);

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

	if (nb)
		blocking_notifier_chain_register(&mbox->notifier, nb);

	return mbox;
}
EXPORT_SYMBOL(omap_mbox_get);

void omap_mbox_put(struct omap_mbox *mbox, struct notifier_block *nb)
{
	blocking_notifier_chain_unregister(&mbox->notifier, nb);
	omap_mbox_fini(mbox);
}
EXPORT_SYMBOL(omap_mbox_put);

static struct class omap_mbox_class = { .name = "mbox", };

int omap_mbox_register(struct device *parent, struct omap_mbox **list)
{
	int ret;
	int i;

	mboxes = list;
	if (!mboxes)
		return -EINVAL;

	for (i = 0; mboxes[i]; i++) {
		struct omap_mbox *mbox = mboxes[i];
		mbox->dev = device_create(&omap_mbox_class,
				parent, 0, mbox, "%s", mbox->name);
		if (IS_ERR(mbox->dev)) {
			ret = PTR_ERR(mbox->dev);
			goto err_out;
		}

		BLOCKING_INIT_NOTIFIER_HEAD(&mbox->notifier);
	}
	return 0;

err_out:
	while (i--)
		device_unregister(mboxes[i]->dev);
	return ret;
}
EXPORT_SYMBOL(omap_mbox_register);

int omap_mbox_unregister(void)
{
	int i;

	if (!mboxes)
		return -EINVAL;

	for (i = 0; mboxes[i]; i++)
		device_unregister(mboxes[i]->dev);
	mboxes = NULL;
	return 0;
}
EXPORT_SYMBOL(omap_mbox_unregister);

static int __init omap_mbox_init(void)
{
	int err;

	err = class_register(&omap_mbox_class);
	if (err)
		return err;

	/* kfifo size sanity check: alignment and minimal size */
	mbox_kfifo_size = ALIGN(mbox_kfifo_size, sizeof(mbox_msg_t));
	mbox_kfifo_size = max_t(unsigned int, mbox_kfifo_size,
							sizeof(mbox_msg_t));

	return 0;
}
subsys_initcall(omap_mbox_init);

static void __exit omap_mbox_exit(void)
{
	class_unregister(&omap_mbox_class);
}
module_exit(omap_mbox_exit);

MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("omap mailbox: interrupt driven messaging");
MODULE_AUTHOR("Toshihiro Kobayashi");
MODULE_AUTHOR("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/interrupt.h>
b3e69146 FC	25	#include <linux/spinlock.h>
b3e69146 FC	26	#include <linux/mutex.h>
340a614a	27	#include <linux/delay.h>
5a0e3ad6	28	#include <linux/slab.h>
b5bebe41 OBC	29	#include <linux/kfifo.h>
b5bebe41 OBC	30	#include <linux/err.h>
58256307	31	#include <linux/notifier.h>
8dff0fa5	32
ce491cf8	33	#include <plat/mailbox.h>
340a614a	34
9c80c8cd	35	static struct omap_mbox **mboxes;
340a614a	36
5f00ec64	37	static int mbox_configured;
72b917ef	38	static DEFINE_MUTEX(mbox_configured_lock);
5f00ec64	39
b5bebe41 OBC	40	static unsigned int mbox_kfifo_size = CONFIG_OMAP_MBOX_KFIFO_SIZE;
	41	module_param(mbox_kfifo_size, uint, S_IRUGO);
	42	MODULE_PARM_DESC(mbox_kfifo_size, "Size of omap's mailbox kfifo (bytes)");
	43
9ae0ee00 HD	44	/* Mailbox FIFO handle functions */
	45	static inline mbox_msg_t mbox_fifo_read(struct omap_mbox *mbox)
	46	{
	47	return mbox->ops->fifo_read(mbox);
	48	}
	49	static inline void mbox_fifo_write(struct omap_mbox *mbox, mbox_msg_t msg)
	50	{
	51	mbox->ops->fifo_write(mbox, msg);
	52	}
	53	static inline int mbox_fifo_empty(struct omap_mbox *mbox)
	54	{
	55	return mbox->ops->fifo_empty(mbox);
	56	}
	57	static inline int mbox_fifo_full(struct omap_mbox *mbox)
	58	{
	59	return mbox->ops->fifo_full(mbox);
	60	}
	61
	62	/* Mailbox IRQ handle functions */
9ae0ee00 HD	63	static inline void ack_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
	64	{
	65	if (mbox->ops->ack_irq)
	66	mbox->ops->ack_irq(mbox, irq);
	67	}
	68	static inline int is_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
	69	{
	70	return mbox->ops->is_irq(mbox, irq);
	71	}
	72
340a614a HD	73	/*
	74	* message sender
	75	*/
b5bebe41	76	static int __mbox_poll_for_space(struct omap_mbox *mbox)
340a614a HD	77	{
	78	int ret = 0, i = 1000;
	79
	80	while (mbox_fifo_full(mbox)) {
	81	if (mbox->ops->type == OMAP_MBOX_TYPE2)
	82	return -1;
	83	if (--i == 0)
	84	return -1;
	85	udelay(1);
	86	}
340a614a HD	87	return ret;
	88	}
	89
b2b6362e	90	int omap_mbox_msg_send(struct omap_mbox *mbox, mbox_msg_t msg)
340a614a	91	{
b5bebe41 OBC	92	struct omap_mbox_queue *mq = mbox->txq;
b5bebe41 OBC	93	int ret = 0, len;
5ed8d32e	94
a42743c2	95	spin_lock_bh(&mq->lock);
ec24751a	96
b5bebe41 OBC	97	if (kfifo_avail(&mq->fifo) < sizeof(msg)) {
	98	ret = -ENOMEM;
	99	goto out;
	100	}
	101
a42743c2 KH	102	if (kfifo_is_empty(&mq->fifo) && !__mbox_poll_for_space(mbox)) {
	103	mbox_fifo_write(mbox, msg);
	104	goto out;
	105	}
	106
b5bebe41 OBC	107	len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
b5bebe41 OBC	108	WARN_ON(len != sizeof(msg));
340a614a	109
5ed8d32e	110	tasklet_schedule(&mbox->txq->tasklet);
340a614a	111
b5bebe41	112	out:
a42743c2	113	spin_unlock_bh(&mq->lock);
b5bebe41	114	return ret;
340a614a HD	115	}
	116	EXPORT_SYMBOL(omap_mbox_msg_send);
	117
5ed8d32e	118	static void mbox_tx_tasklet(unsigned long tx_data)
340a614a	119	{
5ed8d32e	120	struct omap_mbox mbox = (struct omap_mbox )tx_data;
b5bebe41 OBC	121	struct omap_mbox_queue *mq = mbox->txq;
	122	mbox_msg_t msg;
	123	int ret;
340a614a	124
b5bebe41 OBC	125	while (kfifo_len(&mq->fifo)) {
b5bebe41 OBC	126	if (__mbox_poll_for_space(mbox)) {
eb18858e	127	omap_mbox_enable_irq(mbox, IRQ_TX);
b5bebe41	128	break;
340a614a	129	}
b5bebe41 OBC	130
	131	ret = kfifo_out(&mq->fifo, (unsigned char *)&msg,
	132	sizeof(msg));
	133	WARN_ON(ret != sizeof(msg));
	134
	135	mbox_fifo_write(mbox, msg);
340a614a HD	136	}
	137	}
	138
	139	/*
	140	* Message receiver(workqueue)
	141	*/
	142	static void mbox_rx_work(struct work_struct *work)
	143	{
	144	struct omap_mbox_queue *mq =
	145	container_of(work, struct omap_mbox_queue, work);
340a614a	146	mbox_msg_t msg;
b5bebe41 OBC	147	int len;
	148
	149	while (kfifo_len(&mq->fifo) >= sizeof(msg)) {
	150	len = kfifo_out(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
	151	WARN_ON(len != sizeof(msg));
340a614a	152
58256307 KH	153	blocking_notifier_call_chain(&mq->mbox->notifier, len,
58256307 KH	154	(void *)msg);
d2295042 FGL	155	spin_lock_irq(&mq->lock);
	156	if (mq->full) {
	157	mq->full = false;
	158	omap_mbox_enable_irq(mq->mbox, IRQ_RX);
	159	}
	160	spin_unlock_irq(&mq->lock);
340a614a HD	161	}
	162	}
	163
	164	/*
	165	* Mailbox interrupt handler
	166	*/
340a614a HD	167	static void __mbox_tx_interrupt(struct omap_mbox *mbox)
340a614a HD	168	{
eb18858e	169	omap_mbox_disable_irq(mbox, IRQ_TX);
340a614a	170	ack_mbox_irq(mbox, IRQ_TX);
5ed8d32e	171	tasklet_schedule(&mbox->txq->tasklet);
340a614a HD	172	}
	173
	174	static void __mbox_rx_interrupt(struct omap_mbox *mbox)
	175	{
b5bebe41	176	struct omap_mbox_queue *mq = mbox->rxq;
340a614a	177	mbox_msg_t msg;
b5bebe41	178	int len;
340a614a	179
340a614a	180	while (!mbox_fifo_empty(mbox)) {
b5bebe41	181	if (unlikely(kfifo_avail(&mq->fifo) < sizeof(msg))) {
1ea5d6d1	182	omap_mbox_disable_irq(mbox, IRQ_RX);
d2295042	183	mq->full = true;
340a614a	184	goto nomem;
1ea5d6d1	185	}
340a614a HD	186
340a614a HD	187	msg = mbox_fifo_read(mbox);
340a614a	188
b5bebe41 OBC	189	len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
b5bebe41 OBC	190	WARN_ON(len != sizeof(msg));
340a614a	191
340a614a HD	192	if (mbox->ops->type == OMAP_MBOX_TYPE1)
	193	break;
	194	}
	195
	196	/* no more messages in the fifo. clear IRQ source. */
	197	ack_mbox_irq(mbox, IRQ_RX);
f48cca87	198	nomem:
c4873005	199	schedule_work(&mbox->rxq->work);
340a614a HD	200	}
	201
	202	static irqreturn_t mbox_interrupt(int irq, void *p)
	203	{
2a7057e3	204	struct omap_mbox *mbox = p;
340a614a HD	205
	206	if (is_mbox_irq(mbox, IRQ_TX))
	207	__mbox_tx_interrupt(mbox);
	208
	209	if (is_mbox_irq(mbox, IRQ_RX))
	210	__mbox_rx_interrupt(mbox);
	211
	212	return IRQ_HANDLED;
	213	}
	214
340a614a	215	static struct omap_mbox_queue mbox_queue_alloc(struct omap_mbox mbox,
5ed8d32e S	216	void (work) (struct work_struct ),
5ed8d32e S	217	void (*tasklet)(unsigned long))
340a614a	218	{
340a614a HD	219	struct omap_mbox_queue *mq;
	220
	221	mq = kzalloc(sizeof(struct omap_mbox_queue), GFP_KERNEL);
	222	if (!mq)
	223	return NULL;
	224
	225	spin_lock_init(&mq->lock);
	226
b5bebe41	227	if (kfifo_alloc(&mq->fifo, mbox_kfifo_size, GFP_KERNEL))
340a614a	228	goto error;
340a614a	229
5ed8d32e S	230	if (work)
5ed8d32e S	231	INIT_WORK(&mq->work, work);
340a614a	232
5ed8d32e S	233	if (tasklet)
5ed8d32e S	234	tasklet_init(&mq->tasklet, tasklet, (unsigned long)mbox);
340a614a HD	235	return mq;
	236	error:
	237	kfree(mq);
	238	return NULL;
	239	}
	240
	241	static void mbox_queue_free(struct omap_mbox_queue *q)
	242	{
b5bebe41	243	kfifo_free(&q->fifo);
340a614a HD	244	kfree(q);
	245	}
	246
c7c158e5	247	static int omap_mbox_startup(struct omap_mbox *mbox)
340a614a	248	{
5f00ec64	249	int ret = 0;
340a614a HD	250	struct omap_mbox_queue *mq;
340a614a HD	251
58256307 KH	252	mutex_lock(&mbox_configured_lock);
	253	if (!mbox_configured++) {
	254	if (likely(mbox->ops->startup)) {
5f00ec64	255	ret = mbox->ops->startup(mbox);
58256307 KH	256	if (unlikely(ret))
	257	goto fail_startup;
	258	} else
	259	goto fail_startup;
340a614a HD	260	}
340a614a HD	261
58256307 KH	262	if (!mbox->use_count++) {
	263	ret = request_irq(mbox->irq, mbox_interrupt, IRQF_SHARED,
	264	mbox->name, mbox);
	265	if (unlikely(ret)) {
	266	pr_err("failed to register mailbox interrupt:%d\n",
	267	ret);
	268	goto fail_request_irq;
	269	}
	270	mq = mbox_queue_alloc(mbox, NULL, mbox_tx_tasklet);
	271	if (!mq) {
	272	ret = -ENOMEM;
	273	goto fail_alloc_txq;
	274	}
	275	mbox->txq = mq;
340a614a	276
58256307 KH	277	mq = mbox_queue_alloc(mbox, mbox_rx_work, NULL);
	278	if (!mq) {
	279	ret = -ENOMEM;
	280	goto fail_alloc_rxq;
	281	}
	282	mbox->rxq = mq;
	283	mq->mbox = mbox;
340a614a	284	}
58256307	285	mutex_unlock(&mbox_configured_lock);
340a614a HD	286	return 0;
340a614a HD	287
ab66ac30	288	fail_alloc_rxq:
340a614a	289	mbox_queue_free(mbox->txq);
ab66ac30	290	fail_alloc_txq:
340a614a	291	free_irq(mbox->irq, mbox);
ab66ac30	292	fail_request_irq:
01072d8f	293	if (mbox->ops->shutdown)
340a614a	294	mbox->ops->shutdown(mbox);
58256307 KH	295	mbox->use_count--;
	296	fail_startup:
	297	mbox_configured--;
	298	mutex_unlock(&mbox_configured_lock);
340a614a HD	299	return ret;
	300	}
	301
	302	static void omap_mbox_fini(struct omap_mbox *mbox)
	303	{
58256307 KH	304	mutex_lock(&mbox_configured_lock);
	305
	306	if (!--mbox->use_count) {
	307	free_irq(mbox->irq, mbox);
	308	tasklet_kill(&mbox->txq->tasklet);
c4873005	309	flush_work_sync(&mbox->rxq->work);
58256307 KH	310	mbox_queue_free(mbox->txq);
	311	mbox_queue_free(mbox->rxq);
	312	}
340a614a	313
58256307 KH	314	if (likely(mbox->ops->shutdown)) {
58256307 KH	315	if (!--mbox_configured)
5f00ec64	316	mbox->ops->shutdown(mbox);
5f00ec64	317	}
58256307 KH	318
58256307 KH	319	mutex_unlock(&mbox_configured_lock);
340a614a HD	320	}
340a614a HD	321
58256307	322	struct omap_mbox omap_mbox_get(const char name, struct notifier_block *nb)
340a614a	323	{
c0377320 KH	324	struct omap_mbox _mbox, mbox = NULL;
c0377320 KH	325	int i, ret;
340a614a	326
9c80c8cd FC	327	if (!mboxes)
9c80c8cd FC	328	return ERR_PTR(-EINVAL);
340a614a	329
c0377320 KH	330	for (i = 0; (_mbox = mboxes[i]); i++) {
	331	if (!strcmp(_mbox->name, name)) {
	332	mbox = _mbox;
9c80c8cd	333	break;
c0377320 KH	334	}
c0377320 KH	335	}
9c80c8cd FC	336
	337	if (!mbox)
	338	return ERR_PTR(-ENOENT);
340a614a	339
c7c158e5	340	ret = omap_mbox_startup(mbox);
340a614a HD	341	if (ret)
	342	return ERR_PTR(-ENODEV);
	343
58256307 KH	344	if (nb)
	345	blocking_notifier_chain_register(&mbox->notifier, nb);
	346
340a614a HD	347	return mbox;
	348	}
	349	EXPORT_SYMBOL(omap_mbox_get);
	350
58256307	351	void omap_mbox_put(struct omap_mbox mbox, struct notifier_block nb)
340a614a	352	{
58256307	353	blocking_notifier_chain_unregister(&mbox->notifier, nb);
340a614a HD	354	omap_mbox_fini(mbox);
	355	}
	356	EXPORT_SYMBOL(omap_mbox_put);
	357
6b233985 HD	358	static struct class omap_mbox_class = { .name = "mbox", };
6b233985 HD	359
9c80c8cd	360	int omap_mbox_register(struct device parent, struct omap_mbox *list)
340a614a	361	{
9c80c8cd FC	362	int ret;
9c80c8cd FC	363	int i;
340a614a	364
9c80c8cd FC	365	mboxes = list;
9c80c8cd FC	366	if (!mboxes)
340a614a	367	return -EINVAL;
340a614a	368
9c80c8cd FC	369	for (i = 0; mboxes[i]; i++) {
	370	struct omap_mbox *mbox = mboxes[i];
	371	mbox->dev = device_create(&omap_mbox_class,
	372	parent, 0, mbox, "%s", mbox->name);
	373	if (IS_ERR(mbox->dev)) {
	374	ret = PTR_ERR(mbox->dev);
	375	goto err_out;
	376	}
58256307 KH	377
58256307 KH	378	BLOCKING_INIT_NOTIFIER_HEAD(&mbox->notifier);
9c80c8cd	379	}
f48cca87 HD	380	return 0;
f48cca87 HD	381
9c80c8cd FC	382	err_out:
	383	while (i--)
	384	device_unregister(mboxes[i]->dev);
340a614a HD	385	return ret;
	386	}
	387	EXPORT_SYMBOL(omap_mbox_register);
	388
9c80c8cd	389	int omap_mbox_unregister(void)
340a614a	390	{
9c80c8cd	391	int i;
340a614a	392
9c80c8cd FC	393	if (!mboxes)
	394	return -EINVAL;
	395
	396	for (i = 0; mboxes[i]; i++)
	397	device_unregister(mboxes[i]->dev);
	398	mboxes = NULL;
	399	return 0;
340a614a HD	400	}
	401	EXPORT_SYMBOL(omap_mbox_unregister);
	402
c7c158e5	403	static int __init omap_mbox_init(void)
340a614a	404	{
6b233985 HD	405	int err;
	406
	407	err = class_register(&omap_mbox_class);
	408	if (err)
	409	return err;
	410
b5bebe41 OBC	411	/* kfifo size sanity check: alignment and minimal size */
b5bebe41 OBC	412	mbox_kfifo_size = ALIGN(mbox_kfifo_size, sizeof(mbox_msg_t));
ab66ac30 KH	413	mbox_kfifo_size = max_t(unsigned int, mbox_kfifo_size,
ab66ac30 KH	414	sizeof(mbox_msg_t));
b5bebe41	415
c7c158e5	416	return 0;
340a614a	417	}
6b233985	418	subsys_initcall(omap_mbox_init);
340a614a	419
c7c158e5	420	static void __exit omap_mbox_exit(void)
340a614a	421	{
6b233985	422	class_unregister(&omap_mbox_class);
340a614a	423	}
c7c158e5	424	module_exit(omap_mbox_exit);
340a614a	425
f48cca87 HD	426	MODULE_LICENSE("GPL v2");
f48cca87 HD	427	MODULE_DESCRIPTION("omap mailbox: interrupt driven messaging");
f375325a OBC	428	MODULE_AUTHOR("Toshihiro Kobayashi");
f375325a OBC	429	MODULE_AUTHOR("Hiroshi DOYU");