[deliverable/linux.git] / drivers / mailbox / 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 <linux/module.h>

#include "omap-mbox.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);

void omap_mbox_save_ctx(struct omap_mbox *mbox)
{
	if (!mbox->ops->save_ctx) {
		dev_err(mbox->dev, "%s:\tno save\n", __func__);
		return;
	}

	mbox->ops->save_ctx(mbox);
}
EXPORT_SYMBOL(omap_mbox_save_ctx);

void omap_mbox_restore_ctx(struct omap_mbox *mbox)
{
	if (!mbox->ops->restore_ctx) {
		dev_err(mbox->dev, "%s:\tno restore\n", __func__);
		return;
	}

	mbox->ops->restore_ctx(mbox);
}
EXPORT_SYMBOL(omap_mbox_restore_ctx);

void omap_mbox_enable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
{
	mbox->ops->enable_irq(mbox, irq);
}
EXPORT_SYMBOL(omap_mbox_enable_irq);

void omap_mbox_disable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
{
	mbox->ops->disable_irq(mbox, irq);
}
EXPORT_SYMBOL(omap_mbox_disable_irq);

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++) {
		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;
		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;
		}

		omap_mbox_enable_irq(mbox, IRQ_RX);
	}
	mutex_unlock(&mbox_configured_lock);
	return 0;

fail_request_irq:
	mbox_queue_free(mbox->rxq);
fail_alloc_rxq:
	mbox_queue_free(mbox->txq);
fail_alloc_txq:
	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) {
		omap_mbox_disable_irq(mbox, IRQ_RX);
		free_irq(mbox->irq, mbox);
		tasklet_kill(&mbox->txq->tasklet);
		flush_work(&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);

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

	ret = omap_mbox_startup(mbox);
	if (ret) {
		blocking_notifier_chain_unregister(&mbox->notifier, nb);
		return ERR_PTR(-ENODEV);
	}

	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>
73017a54	32	#include <linux/module.h>
8dff0fa5	33
c869c75c	34	#include "omap-mbox.h"
340a614a	35
9c80c8cd	36	static struct omap_mbox **mboxes;
340a614a	37
5f00ec64	38	static int mbox_configured;
72b917ef	39	static DEFINE_MUTEX(mbox_configured_lock);
5f00ec64	40
b5bebe41 OBC	41	static unsigned int mbox_kfifo_size = CONFIG_OMAP_MBOX_KFIFO_SIZE;
	42	module_param(mbox_kfifo_size, uint, S_IRUGO);
	43	MODULE_PARM_DESC(mbox_kfifo_size, "Size of omap's mailbox kfifo (bytes)");
	44
9ae0ee00 HD	45	/* Mailbox FIFO handle functions */
	46	static inline mbox_msg_t mbox_fifo_read(struct omap_mbox *mbox)
	47	{
	48	return mbox->ops->fifo_read(mbox);
	49	}
	50	static inline void mbox_fifo_write(struct omap_mbox *mbox, mbox_msg_t msg)
	51	{
	52	mbox->ops->fifo_write(mbox, msg);
	53	}
	54	static inline int mbox_fifo_empty(struct omap_mbox *mbox)
	55	{
	56	return mbox->ops->fifo_empty(mbox);
	57	}
	58	static inline int mbox_fifo_full(struct omap_mbox *mbox)
	59	{
	60	return mbox->ops->fifo_full(mbox);
	61	}
	62
	63	/* Mailbox IRQ handle functions */
9ae0ee00 HD	64	static inline void ack_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
	65	{
	66	if (mbox->ops->ack_irq)
	67	mbox->ops->ack_irq(mbox, irq);
	68	}
	69	static inline int is_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
	70	{
	71	return mbox->ops->is_irq(mbox, irq);
	72	}
	73
340a614a HD	74	/*
	75	* message sender
	76	*/
b5bebe41	77	static int __mbox_poll_for_space(struct omap_mbox *mbox)
340a614a HD	78	{
	79	int ret = 0, i = 1000;
	80
	81	while (mbox_fifo_full(mbox)) {
	82	if (mbox->ops->type == OMAP_MBOX_TYPE2)
	83	return -1;
	84	if (--i == 0)
	85	return -1;
	86	udelay(1);
	87	}
340a614a HD	88	return ret;
	89	}
	90
b2b6362e	91	int omap_mbox_msg_send(struct omap_mbox *mbox, mbox_msg_t msg)
340a614a	92	{
b5bebe41 OBC	93	struct omap_mbox_queue *mq = mbox->txq;
b5bebe41 OBC	94	int ret = 0, len;
5ed8d32e	95
a42743c2	96	spin_lock_bh(&mq->lock);
ec24751a	97
b5bebe41 OBC	98	if (kfifo_avail(&mq->fifo) < sizeof(msg)) {
	99	ret = -ENOMEM;
	100	goto out;
	101	}
	102
a42743c2 KH	103	if (kfifo_is_empty(&mq->fifo) && !__mbox_poll_for_space(mbox)) {
	104	mbox_fifo_write(mbox, msg);
	105	goto out;
	106	}
	107
b5bebe41 OBC	108	len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
b5bebe41 OBC	109	WARN_ON(len != sizeof(msg));
340a614a	110
5ed8d32e	111	tasklet_schedule(&mbox->txq->tasklet);
340a614a	112
b5bebe41	113	out:
a42743c2	114	spin_unlock_bh(&mq->lock);
b5bebe41	115	return ret;
340a614a HD	116	}
	117	EXPORT_SYMBOL(omap_mbox_msg_send);
	118
c869c75c SA	119	void omap_mbox_save_ctx(struct omap_mbox *mbox)
	120	{
	121	if (!mbox->ops->save_ctx) {
	122	dev_err(mbox->dev, "%s:\tno save\n", __func__);
	123	return;
	124	}
	125
	126	mbox->ops->save_ctx(mbox);
	127	}
	128	EXPORT_SYMBOL(omap_mbox_save_ctx);
	129
	130	void omap_mbox_restore_ctx(struct omap_mbox *mbox)
	131	{
	132	if (!mbox->ops->restore_ctx) {
	133	dev_err(mbox->dev, "%s:\tno restore\n", __func__);
	134	return;
	135	}
	136
	137	mbox->ops->restore_ctx(mbox);
	138	}
	139	EXPORT_SYMBOL(omap_mbox_restore_ctx);
	140
	141	void omap_mbox_enable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
	142	{
	143	mbox->ops->enable_irq(mbox, irq);
	144	}
	145	EXPORT_SYMBOL(omap_mbox_enable_irq);
	146
	147	void omap_mbox_disable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
	148	{
	149	mbox->ops->disable_irq(mbox, irq);
	150	}
	151	EXPORT_SYMBOL(omap_mbox_disable_irq);
	152
5ed8d32e	153	static void mbox_tx_tasklet(unsigned long tx_data)
340a614a	154	{
5ed8d32e	155	struct omap_mbox mbox = (struct omap_mbox )tx_data;
b5bebe41 OBC	156	struct omap_mbox_queue *mq = mbox->txq;
	157	mbox_msg_t msg;
	158	int ret;
340a614a	159
b5bebe41 OBC	160	while (kfifo_len(&mq->fifo)) {
b5bebe41 OBC	161	if (__mbox_poll_for_space(mbox)) {
eb18858e	162	omap_mbox_enable_irq(mbox, IRQ_TX);
b5bebe41	163	break;
340a614a	164	}
b5bebe41 OBC	165
	166	ret = kfifo_out(&mq->fifo, (unsigned char *)&msg,
	167	sizeof(msg));
	168	WARN_ON(ret != sizeof(msg));
	169
	170	mbox_fifo_write(mbox, msg);
340a614a HD	171	}
	172	}
	173
	174	/*
	175	* Message receiver(workqueue)
	176	*/
	177	static void mbox_rx_work(struct work_struct *work)
	178	{
	179	struct omap_mbox_queue *mq =
	180	container_of(work, struct omap_mbox_queue, work);
340a614a	181	mbox_msg_t msg;
b5bebe41 OBC	182	int len;
	183
	184	while (kfifo_len(&mq->fifo) >= sizeof(msg)) {
	185	len = kfifo_out(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
	186	WARN_ON(len != sizeof(msg));
340a614a	187
58256307 KH	188	blocking_notifier_call_chain(&mq->mbox->notifier, len,
58256307 KH	189	(void *)msg);
d2295042 FGL	190	spin_lock_irq(&mq->lock);
	191	if (mq->full) {
	192	mq->full = false;
	193	omap_mbox_enable_irq(mq->mbox, IRQ_RX);
	194	}
	195	spin_unlock_irq(&mq->lock);
340a614a HD	196	}
	197	}
	198
	199	/*
	200	* Mailbox interrupt handler
	201	*/
340a614a HD	202	static void __mbox_tx_interrupt(struct omap_mbox *mbox)
340a614a HD	203	{
eb18858e	204	omap_mbox_disable_irq(mbox, IRQ_TX);
340a614a	205	ack_mbox_irq(mbox, IRQ_TX);
5ed8d32e	206	tasklet_schedule(&mbox->txq->tasklet);
340a614a HD	207	}
	208
	209	static void __mbox_rx_interrupt(struct omap_mbox *mbox)
	210	{
b5bebe41	211	struct omap_mbox_queue *mq = mbox->rxq;
340a614a	212	mbox_msg_t msg;
b5bebe41	213	int len;
340a614a	214
340a614a	215	while (!mbox_fifo_empty(mbox)) {
b5bebe41	216	if (unlikely(kfifo_avail(&mq->fifo) < sizeof(msg))) {
1ea5d6d1	217	omap_mbox_disable_irq(mbox, IRQ_RX);
d2295042	218	mq->full = true;
340a614a	219	goto nomem;
1ea5d6d1	220	}
340a614a HD	221
340a614a HD	222	msg = mbox_fifo_read(mbox);
340a614a	223
b5bebe41 OBC	224	len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
b5bebe41 OBC	225	WARN_ON(len != sizeof(msg));
340a614a	226
340a614a HD	227	if (mbox->ops->type == OMAP_MBOX_TYPE1)
	228	break;
	229	}
	230
	231	/* no more messages in the fifo. clear IRQ source. */
	232	ack_mbox_irq(mbox, IRQ_RX);
f48cca87	233	nomem:
c4873005	234	schedule_work(&mbox->rxq->work);
340a614a HD	235	}
	236
	237	static irqreturn_t mbox_interrupt(int irq, void *p)
	238	{
2a7057e3	239	struct omap_mbox *mbox = p;
340a614a HD	240
	241	if (is_mbox_irq(mbox, IRQ_TX))
	242	__mbox_tx_interrupt(mbox);
	243
	244	if (is_mbox_irq(mbox, IRQ_RX))
	245	__mbox_rx_interrupt(mbox);
	246
	247	return IRQ_HANDLED;
	248	}
	249
340a614a	250	static struct omap_mbox_queue mbox_queue_alloc(struct omap_mbox mbox,
5ed8d32e S	251	void (work) (struct work_struct ),
5ed8d32e S	252	void (*tasklet)(unsigned long))
340a614a	253	{
340a614a HD	254	struct omap_mbox_queue *mq;
	255
	256	mq = kzalloc(sizeof(struct omap_mbox_queue), GFP_KERNEL);
	257	if (!mq)
	258	return NULL;
	259
	260	spin_lock_init(&mq->lock);
	261
b5bebe41	262	if (kfifo_alloc(&mq->fifo, mbox_kfifo_size, GFP_KERNEL))
340a614a	263	goto error;
340a614a	264
5ed8d32e S	265	if (work)
5ed8d32e S	266	INIT_WORK(&mq->work, work);
340a614a	267
5ed8d32e S	268	if (tasklet)
5ed8d32e S	269	tasklet_init(&mq->tasklet, tasklet, (unsigned long)mbox);
340a614a HD	270	return mq;
	271	error:
	272	kfree(mq);
	273	return NULL;
	274	}
	275
	276	static void mbox_queue_free(struct omap_mbox_queue *q)
	277	{
b5bebe41	278	kfifo_free(&q->fifo);
340a614a HD	279	kfree(q);
	280	}
	281
c7c158e5	282	static int omap_mbox_startup(struct omap_mbox *mbox)
340a614a	283	{
5f00ec64	284	int ret = 0;
340a614a HD	285	struct omap_mbox_queue *mq;
340a614a HD	286
58256307 KH	287	mutex_lock(&mbox_configured_lock);
	288	if (!mbox_configured++) {
	289	if (likely(mbox->ops->startup)) {
5f00ec64	290	ret = mbox->ops->startup(mbox);
58256307 KH	291	if (unlikely(ret))
	292	goto fail_startup;
	293	} else
	294	goto fail_startup;
340a614a HD	295	}
340a614a HD	296
58256307	297	if (!mbox->use_count++) {
58256307 KH	298	mq = mbox_queue_alloc(mbox, NULL, mbox_tx_tasklet);
	299	if (!mq) {
	300	ret = -ENOMEM;
	301	goto fail_alloc_txq;
	302	}
	303	mbox->txq = mq;
340a614a	304
58256307 KH	305	mq = mbox_queue_alloc(mbox, mbox_rx_work, NULL);
	306	if (!mq) {
	307	ret = -ENOMEM;
	308	goto fail_alloc_rxq;
	309	}
	310	mbox->rxq = mq;
	311	mq->mbox = mbox;
ecf305cf SA	312	ret = request_irq(mbox->irq, mbox_interrupt, IRQF_SHARED,
	313	mbox->name, mbox);
	314	if (unlikely(ret)) {
	315	pr_err("failed to register mailbox interrupt:%d\n",
	316	ret);
	317	goto fail_request_irq;
	318	}
1d8a0e96 JG	319
1d8a0e96 JG	320	omap_mbox_enable_irq(mbox, IRQ_RX);
340a614a	321	}
58256307	322	mutex_unlock(&mbox_configured_lock);
340a614a HD	323	return 0;
340a614a HD	324
ecf305cf SA	325	fail_request_irq:
ecf305cf SA	326	mbox_queue_free(mbox->rxq);
ab66ac30	327	fail_alloc_rxq:
340a614a	328	mbox_queue_free(mbox->txq);
ab66ac30	329	fail_alloc_txq:
01072d8f	330	if (mbox->ops->shutdown)
340a614a	331	mbox->ops->shutdown(mbox);
58256307 KH	332	mbox->use_count--;
	333	fail_startup:
	334	mbox_configured--;
	335	mutex_unlock(&mbox_configured_lock);
340a614a HD	336	return ret;
	337	}
	338
	339	static void omap_mbox_fini(struct omap_mbox *mbox)
	340	{
58256307 KH	341	mutex_lock(&mbox_configured_lock);
	342
	343	if (!--mbox->use_count) {
1d8a0e96	344	omap_mbox_disable_irq(mbox, IRQ_RX);
58256307 KH	345	free_irq(mbox->irq, mbox);
58256307 KH	346	tasklet_kill(&mbox->txq->tasklet);
43829731	347	flush_work(&mbox->rxq->work);
58256307 KH	348	mbox_queue_free(mbox->txq);
	349	mbox_queue_free(mbox->rxq);
	350	}
340a614a	351
58256307 KH	352	if (likely(mbox->ops->shutdown)) {
58256307 KH	353	if (!--mbox_configured)
5f00ec64	354	mbox->ops->shutdown(mbox);
5f00ec64	355	}
58256307 KH	356
58256307 KH	357	mutex_unlock(&mbox_configured_lock);
340a614a HD	358	}
340a614a HD	359
58256307	360	struct omap_mbox omap_mbox_get(const char name, struct notifier_block *nb)
340a614a	361	{
c0377320 KH	362	struct omap_mbox _mbox, mbox = NULL;
c0377320 KH	363	int i, ret;
340a614a	364
9c80c8cd FC	365	if (!mboxes)
9c80c8cd FC	366	return ERR_PTR(-EINVAL);
340a614a	367
c0377320 KH	368	for (i = 0; (_mbox = mboxes[i]); i++) {
	369	if (!strcmp(_mbox->name, name)) {
	370	mbox = _mbox;
9c80c8cd	371	break;
c0377320 KH	372	}
c0377320 KH	373	}
9c80c8cd FC	374
	375	if (!mbox)
	376	return ERR_PTR(-ENOENT);
340a614a	377
58256307 KH	378	if (nb)
	379	blocking_notifier_chain_register(&mbox->notifier, nb);
	380
1d8a0e96 JG	381	ret = omap_mbox_startup(mbox);
	382	if (ret) {
	383	blocking_notifier_chain_unregister(&mbox->notifier, nb);
	384	return ERR_PTR(-ENODEV);
	385	}
	386
340a614a HD	387	return mbox;
	388	}
	389	EXPORT_SYMBOL(omap_mbox_get);
	390
58256307	391	void omap_mbox_put(struct omap_mbox mbox, struct notifier_block nb)
340a614a	392	{
58256307	393	blocking_notifier_chain_unregister(&mbox->notifier, nb);
340a614a HD	394	omap_mbox_fini(mbox);
	395	}
	396	EXPORT_SYMBOL(omap_mbox_put);
	397
6b233985 HD	398	static struct class omap_mbox_class = { .name = "mbox", };
6b233985 HD	399
9c80c8cd	400	int omap_mbox_register(struct device parent, struct omap_mbox *list)
340a614a	401	{
9c80c8cd FC	402	int ret;
9c80c8cd FC	403	int i;
340a614a	404
9c80c8cd FC	405	mboxes = list;
9c80c8cd FC	406	if (!mboxes)
340a614a	407	return -EINVAL;
340a614a	408
9c80c8cd FC	409	for (i = 0; mboxes[i]; i++) {
	410	struct omap_mbox *mbox = mboxes[i];
	411	mbox->dev = device_create(&omap_mbox_class,
	412	parent, 0, mbox, "%s", mbox->name);
	413	if (IS_ERR(mbox->dev)) {
	414	ret = PTR_ERR(mbox->dev);
	415	goto err_out;
	416	}
58256307 KH	417
58256307 KH	418	BLOCKING_INIT_NOTIFIER_HEAD(&mbox->notifier);
9c80c8cd	419	}
f48cca87 HD	420	return 0;
f48cca87 HD	421
9c80c8cd FC	422	err_out:
	423	while (i--)
	424	device_unregister(mboxes[i]->dev);
340a614a HD	425	return ret;
	426	}
	427	EXPORT_SYMBOL(omap_mbox_register);
	428
9c80c8cd	429	int omap_mbox_unregister(void)
340a614a	430	{
9c80c8cd	431	int i;
340a614a	432
9c80c8cd FC	433	if (!mboxes)
	434	return -EINVAL;
	435
	436	for (i = 0; mboxes[i]; i++)
	437	device_unregister(mboxes[i]->dev);
	438	mboxes = NULL;
	439	return 0;
340a614a HD	440	}
	441	EXPORT_SYMBOL(omap_mbox_unregister);
	442
c7c158e5	443	static int __init omap_mbox_init(void)
340a614a	444	{
6b233985 HD	445	int err;
	446
	447	err = class_register(&omap_mbox_class);
	448	if (err)
	449	return err;
	450
b5bebe41 OBC	451	/* kfifo size sanity check: alignment and minimal size */
b5bebe41 OBC	452	mbox_kfifo_size = ALIGN(mbox_kfifo_size, sizeof(mbox_msg_t));
ab66ac30 KH	453	mbox_kfifo_size = max_t(unsigned int, mbox_kfifo_size,
ab66ac30 KH	454	sizeof(mbox_msg_t));
b5bebe41	455
c7c158e5	456	return 0;
340a614a	457	}
6b233985	458	subsys_initcall(omap_mbox_init);
340a614a	459
c7c158e5	460	static void __exit omap_mbox_exit(void)
340a614a	461	{
6b233985	462	class_unregister(&omap_mbox_class);
340a614a	463	}
c7c158e5	464	module_exit(omap_mbox_exit);
340a614a	465
f48cca87 HD	466	MODULE_LICENSE("GPL v2");
f48cca87 HD	467	MODULE_DESCRIPTION("omap mailbox: interrupt driven messaging");
f375325a OBC	468	MODULE_AUTHOR("Toshihiro Kobayashi");
f375325a OBC	469	MODULE_AUTHOR("Hiroshi DOYU");