[mirror_ubuntu-artful-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/init.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/interrupt.h>
#include <linux/device.h>
#include <linux/blkdev.h>
#include <linux/err.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <mach/mailbox.h>
#include "mailbox.h"

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

/* Mailbox Sequence Bit function */
void omap_mbox_init_seq(struct omap_mbox *mbox)
{
	mbox_seq_init(mbox);
}
EXPORT_SYMBOL(omap_mbox_init_seq);

/*
 * message sender
 */
static int __mbox_msg_send(struct omap_mbox *mbox, mbox_msg_t msg, void *arg)
{
	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);
	}

	if (arg && mbox->txq->callback) {
		ret = mbox->txq->callback(arg);
		if (ret)
			goto out;
	}

	mbox_seq_toggle(mbox, &msg);
	mbox_fifo_write(mbox, msg);
 out:
	return ret;
}

int omap_mbox_msg_send(struct omap_mbox *mbox, mbox_msg_t msg, void* arg)
{
	struct request *rq;
	struct request_queue *q = mbox->txq->queue;
	int ret = 0;

	rq = blk_get_request(q, WRITE, GFP_ATOMIC);
	if (unlikely(!rq)) {
		ret = -ENOMEM;
		goto fail;
	}

	rq->data = (void *)msg;
	blk_insert_request(q, rq, 0, arg);

	schedule_work(&mbox->txq->work);
 fail:
	return ret;
}
EXPORT_SYMBOL(omap_mbox_msg_send);

static void mbox_tx_work(struct work_struct *work)
{
	int ret;
	struct request *rq;
	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->txq->queue;

	while (1) {
		spin_lock(q->queue_lock);
		rq = elv_next_request(q);
		spin_unlock(q->queue_lock);

		if (!rq)
			break;

		ret = __mbox_msg_send(mbox, (mbox_msg_t) rq->data, rq->special);
		if (ret) {
			enable_mbox_irq(mbox, IRQ_TX);
			return;
		}

		spin_lock(q->queue_lock);
		if (__blk_end_request(rq, 0, 0))
			BUG();
		spin_unlock(q->queue_lock);
	}
}

/*
 * 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;

	if (mbox->rxq->callback == NULL) {
		sysfs_notify(&mbox->dev->kobj, NULL, "mbox");
		return;
	}

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

		msg = (mbox_msg_t) rq->data;

		if (blk_end_request(rq, 0, 0))
			BUG();

		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)
{
	disable_mbox_irq(mbox, IRQ_TX);
	ack_mbox_irq(mbox, IRQ_TX);
	schedule_work(&mbox->txq->work);
}

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

	disable_mbox_irq(mbox, IRQ_RX);

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

		msg = mbox_fifo_read(mbox);
		rq->data = (void *)msg;

		if (unlikely(mbox_seq_test(mbox, msg))) {
			pr_info("mbox: Illegal seq bit!(%08x)\n", msg);
			if (mbox->err_notify)
				mbox->err_notify();
		}

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

	/* no more messages in the fifo. clear IRQ source. */
	ack_mbox_irq(mbox, IRQ_RX);
	enable_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;
}

/*
 * sysfs files
 */
static ssize_t
omap_mbox_write(struct device *dev, struct device_attribute *attr,
		const char * buf, size_t count)
{
	int ret;
	mbox_msg_t *p = (mbox_msg_t *)buf;
	struct omap_mbox *mbox = dev_get_drvdata(dev);

	for (; count >= sizeof(mbox_msg_t); count -= sizeof(mbox_msg_t)) {
		ret = omap_mbox_msg_send(mbox, be32_to_cpu(*p), NULL);
		if (ret)
			return -EAGAIN;
		p++;
	}

	return (size_t)((char *)p - buf);
}

static ssize_t
omap_mbox_read(struct device *dev, struct device_attribute *attr, char *buf)
{
	unsigned long flags;
	struct request *rq;
	mbox_msg_t *p = (mbox_msg_t *) buf;
	struct omap_mbox *mbox = dev_get_drvdata(dev);
	struct request_queue *q = mbox->rxq->queue;

	while (1) {
		spin_lock_irqsave(q->queue_lock, flags);
		rq = elv_next_request(q);
		spin_unlock_irqrestore(q->queue_lock, flags);

		if (!rq)
			break;

		*p = (mbox_msg_t) rq->data;

		if (blk_end_request(rq, 0, 0))
			BUG();

		if (unlikely(mbox_seq_test(mbox, *p))) {
			pr_info("mbox: Illegal seq bit!(%08x) ignored\n", *p);
			continue;
		}
		p++;
	}

	pr_debug("%02x %02x %02x %02x\n", buf[0], buf[1], buf[2], buf[3]);

	return (size_t) ((char *)p - buf);
}

static DEVICE_ATTR(mbox, S_IRUGO | S_IWUSR, omap_mbox_read, omap_mbox_write);

static ssize_t mbox_show(struct class *class, char *buf)
{
	return sprintf(buf, "mbox");
}

static CLASS_ATTR(mbox, S_IRUGO, mbox_show, NULL);

static struct class omap_mbox_class = {
	.name = "omap-mailbox",
};

static struct omap_mbox_queue *mbox_queue_alloc(struct omap_mbox *mbox,
					request_fn_proc * proc,
					void (*work) (struct work_struct *))
{
	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;

	INIT_WORK(&mq->work, work);

	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_init(struct omap_mbox *mbox)
{
	int ret;
	struct omap_mbox_queue *mq;

	if (likely(mbox->ops->startup)) {
		ret = mbox->ops->startup(mbox);
		if (unlikely(ret))
			return ret;
	}

	ret = request_irq(mbox->irq, mbox_interrupt, IRQF_DISABLED,
				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, mbox_tx_work);
	if (!mq) {
		ret = -ENOMEM;
		goto fail_alloc_txq;
	}
	mbox->txq = mq;

	mq = mbox_queue_alloc(mbox, mbox_rxq_fn, mbox_rx_work);
	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))
		mbox->ops->shutdown(mbox);
}

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_init(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;

	mbox->dev = device_create(&omap_mbox_class,
				  parent, 0, mbox, "%s", mbox->name);
	if (IS_ERR(mbox->dev))
		return PTR_ERR(mbox->dev);

	ret = device_create_file(mbox->dev, &dev_attr_mbox);
	if (ret)
		goto err_sysfs;

	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:
	device_remove_file(mbox->dev, &dev_attr_mbox);
err_sysfs:
	device_unregister(mbox->dev);
	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);
			device_remove_file(mbox->dev, &dev_attr_mbox);
			device_unregister(mbox->dev);
			return 0;
		}
		tmp = &(*tmp)->next;
	}
	write_unlock(&mboxes_lock);

	return -EINVAL;
}
EXPORT_SYMBOL(omap_mbox_unregister);

static int __init omap_mbox_class_init(void)
{
	int ret = class_register(&omap_mbox_class);
	if (!ret)
		ret = class_create_file(&omap_mbox_class, &class_attr_mbox);

	return ret;
}

static void __exit omap_mbox_class_exit(void)
{
	class_remove_file(&omap_mbox_class, &class_attr_mbox);
	class_unregister(&omap_mbox_class);
}

subsys_initcall(omap_mbox_class_init);
module_exit(omap_mbox_class_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
	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>
fced80c7	32	#include <linux/io.h>
a09e64fb	33	#include <mach/mailbox.h>
340a614a HD	34	#include "mailbox.h"
	35
	36	static struct omap_mbox *mboxes;
	37	static DEFINE_RWLOCK(mboxes_lock);
	38
	39	/* Mailbox Sequence Bit function */
	40	void omap_mbox_init_seq(struct omap_mbox *mbox)
	41	{
	42	mbox_seq_init(mbox);
	43	}
	44	EXPORT_SYMBOL(omap_mbox_init_seq);
	45
	46	/*
	47	* message sender
	48	*/
	49	static int __mbox_msg_send(struct omap_mbox mbox, mbox_msg_t msg, void arg)
	50	{
	51	int ret = 0, i = 1000;
	52
	53	while (mbox_fifo_full(mbox)) {
	54	if (mbox->ops->type == OMAP_MBOX_TYPE2)
	55	return -1;
	56	if (--i == 0)
	57	return -1;
	58	udelay(1);
	59	}
	60
	61	if (arg && mbox->txq->callback) {
	62	ret = mbox->txq->callback(arg);
	63	if (ret)
	64	goto out;
	65	}
	66
	67	mbox_seq_toggle(mbox, &msg);
	68	mbox_fifo_write(mbox, msg);
	69	out:
	70	return ret;
	71	}
	72
	73	int omap_mbox_msg_send(struct omap_mbox mbox, mbox_msg_t msg, void arg)
	74	{
	75	struct request *rq;
	76	struct request_queue *q = mbox->txq->queue;
	77	int ret = 0;
	78
	79	rq = blk_get_request(q, WRITE, GFP_ATOMIC);
	80	if (unlikely(!rq)) {
	81	ret = -ENOMEM;
	82	goto fail;
	83	}
	84
	85	rq->data = (void *)msg;
	86	blk_insert_request(q, rq, 0, arg);
	87
	88	schedule_work(&mbox->txq->work);
	89	fail:
	90	return ret;
	91	}
	92	EXPORT_SYMBOL(omap_mbox_msg_send);
	93
	94	static void mbox_tx_work(struct work_struct *work)
	95	{
	96	int ret;
	97	struct request *rq;
98	struct omap_mbox_queue *mq = container_of(work,
99	struct omap_mbox_queue, work);
100	struct omap_mbox *mbox = mq->queue->queuedata;
101	struct request_queue *q = mbox->txq->queue;
102
103	while (1) {
104	spin_lock(q->queue_lock);
105	rq = elv_next_request(q);
106	spin_unlock(q->queue_lock);
107
108	if (!rq)
109	break;
110
111	ret = __mbox_msg_send(mbox, (mbox_msg_t) rq->data, rq->special);
112	if (ret) {
113	enable_mbox_irq(mbox, IRQ_TX);
114	return;
115	}
116
117	spin_lock(q->queue_lock);
650e9cfd KU	118	if (__blk_end_request(rq, 0, 0))
650e9cfd KU	119	BUG();
340a614a HD	120	spin_unlock(q->queue_lock);
	121	}
	122	}
	123
	124	/*
	125	* Message receiver(workqueue)
	126	*/
	127	static void mbox_rx_work(struct work_struct *work)
	128	{
	129	struct omap_mbox_queue *mq =
	130	container_of(work, struct omap_mbox_queue, work);
	131	struct omap_mbox *mbox = mq->queue->queuedata;
	132	struct request_queue *q = mbox->rxq->queue;
	133	struct request *rq;
	134	mbox_msg_t msg;
	135	unsigned long flags;
	136
	137	if (mbox->rxq->callback == NULL) {
f48cca87	138	sysfs_notify(&mbox->dev->kobj, NULL, "mbox");
340a614a HD	139	return;
	140	}
	141
	142	while (1) {
	143	spin_lock_irqsave(q->queue_lock, flags);
	144	rq = elv_next_request(q);
	145	spin_unlock_irqrestore(q->queue_lock, flags);
	146	if (!rq)
	147	break;
	148
	149	msg = (mbox_msg_t) rq->data;
	150
650e9cfd KU	151	if (blk_end_request(rq, 0, 0))
650e9cfd KU	152	BUG();
340a614a HD	153
	154	mbox->rxq->callback((void *)msg);
	155	}
	156	}
	157
	158	/*
	159	* Mailbox interrupt handler
	160	*/
165125e1	161	static void mbox_txq_fn(struct request_queue * q)
340a614a HD	162	{
	163	}
	164
165125e1	165	static void mbox_rxq_fn(struct request_queue * q)
340a614a HD	166	{
	167	}
	168
	169	static void __mbox_tx_interrupt(struct omap_mbox *mbox)
	170	{
	171	disable_mbox_irq(mbox, IRQ_TX);
	172	ack_mbox_irq(mbox, IRQ_TX);
	173	schedule_work(&mbox->txq->work);
	174	}
	175
	176	static void __mbox_rx_interrupt(struct omap_mbox *mbox)
	177	{
	178	struct request *rq;
	179	mbox_msg_t msg;
165125e1	180	struct request_queue *q = mbox->rxq->queue;
340a614a HD	181
	182	disable_mbox_irq(mbox, IRQ_RX);
	183
	184	while (!mbox_fifo_empty(mbox)) {
	185	rq = blk_get_request(q, WRITE, GFP_ATOMIC);
	186	if (unlikely(!rq))
	187	goto nomem;
	188
	189	msg = mbox_fifo_read(mbox);
	190	rq->data = (void *)msg;
	191
	192	if (unlikely(mbox_seq_test(mbox, msg))) {
	193	pr_info("mbox: Illegal seq bit!(%08x)\n", msg);
	194	if (mbox->err_notify)
	195	mbox->err_notify();
	196	}
	197
	198	blk_insert_request(q, rq, 0, NULL);
	199	if (mbox->ops->type == OMAP_MBOX_TYPE1)
	200	break;
	201	}
	202
	203	/* no more messages in the fifo. clear IRQ source. */
	204	ack_mbox_irq(mbox, IRQ_RX);
	205	enable_mbox_irq(mbox, IRQ_RX);
f48cca87	206	nomem:
340a614a HD	207	schedule_work(&mbox->rxq->work);
	208	}
	209
	210	static irqreturn_t mbox_interrupt(int irq, void *p)
	211	{
2a7057e3	212	struct omap_mbox *mbox = p;
340a614a HD	213
	214	if (is_mbox_irq(mbox, IRQ_TX))
	215	__mbox_tx_interrupt(mbox);
	216
	217	if (is_mbox_irq(mbox, IRQ_RX))
	218	__mbox_rx_interrupt(mbox);
	219
	220	return IRQ_HANDLED;
	221	}
	222
	223	/*
	224	* sysfs files
	225	*/
	226	static ssize_t
	227	omap_mbox_write(struct device dev, struct device_attribute attr,
	228	const char * buf, size_t count)
	229	{
	230	int ret;
	231	mbox_msg_t p = (mbox_msg_t )buf;
	232	struct omap_mbox *mbox = dev_get_drvdata(dev);
	233
	234	for (; count >= sizeof(mbox_msg_t); count -= sizeof(mbox_msg_t)) {
	235	ret = omap_mbox_msg_send(mbox, be32_to_cpu(*p), NULL);
	236	if (ret)
	237	return -EAGAIN;
	238	p++;
	239	}
	240
	241	return (size_t)((char *)p - buf);
	242	}
	243
	244	static ssize_t
	245	omap_mbox_read(struct device dev, struct device_attribute attr, char *buf)
	246	{
	247	unsigned long flags;
	248	struct request *rq;
	249	mbox_msg_t p = (mbox_msg_t ) buf;
	250	struct omap_mbox *mbox = dev_get_drvdata(dev);
	251	struct request_queue *q = mbox->rxq->queue;
	252
	253	while (1) {
	254	spin_lock_irqsave(q->queue_lock, flags);
	255	rq = elv_next_request(q);
	256	spin_unlock_irqrestore(q->queue_lock, flags);
	257
	258	if (!rq)
	259	break;
	260
	261	*p = (mbox_msg_t) rq->data;
	262
650e9cfd KU	263	if (blk_end_request(rq, 0, 0))
650e9cfd KU	264	BUG();
340a614a HD	265
	266	if (unlikely(mbox_seq_test(mbox, *p))) {
	267	pr_info("mbox: Illegal seq bit!(%08x) ignored\n", *p);
	268	continue;
	269	}
	270	p++;
	271	}
	272
	273	pr_debug("%02x %02x %02x %02x\n", buf[0], buf[1], buf[2], buf[3]);
	274
	275	return (size_t) ((char *)p - buf);
	276	}
	277
	278	static DEVICE_ATTR(mbox, S_IRUGO \| S_IWUSR, omap_mbox_read, omap_mbox_write);
	279
	280	static ssize_t mbox_show(struct class class, char buf)
	281	{
	282	return sprintf(buf, "mbox");
	283	}
	284
	285	static CLASS_ATTR(mbox, S_IRUGO, mbox_show, NULL);
	286
	287	static struct class omap_mbox_class = {
f48cca87	288	.name = "omap-mailbox",
340a614a HD	289	};
	290
	291	static struct omap_mbox_queue mbox_queue_alloc(struct omap_mbox mbox,
	292	request_fn_proc * proc,
	293	void (work) (struct work_struct ))
	294	{
165125e1	295	struct request_queue *q;
340a614a HD	296	struct omap_mbox_queue *mq;
	297
	298	mq = kzalloc(sizeof(struct omap_mbox_queue), GFP_KERNEL);
	299	if (!mq)
	300	return NULL;
	301
	302	spin_lock_init(&mq->lock);
	303
	304	q = blk_init_queue(proc, &mq->lock);
	305	if (!q)
	306	goto error;
	307	q->queuedata = mbox;
	308	mq->queue = q;
	309
	310	INIT_WORK(&mq->work, work);
	311
	312	return mq;
	313	error:
	314	kfree(mq);
	315	return NULL;
	316	}
	317
	318	static void mbox_queue_free(struct omap_mbox_queue *q)
	319	{
	320	blk_cleanup_queue(q->queue);
	321	kfree(q);
	322	}
	323
	324	static int omap_mbox_init(struct omap_mbox *mbox)
	325	{
	326	int ret;
	327	struct omap_mbox_queue *mq;
	328
	329	if (likely(mbox->ops->startup)) {
	330	ret = mbox->ops->startup(mbox);
	331	if (unlikely(ret))
	332	return ret;
	333	}
	334
340a614a HD	335	ret = request_irq(mbox->irq, mbox_interrupt, IRQF_DISABLED,
	336	mbox->name, mbox);
	337	if (unlikely(ret)) {
	338	printk(KERN_ERR
	339	"failed to register mailbox interrupt:%d\n", ret);
	340	goto fail_request_irq;
	341	}
340a614a HD	342
	343	mq = mbox_queue_alloc(mbox, mbox_txq_fn, mbox_tx_work);
	344	if (!mq) {
	345	ret = -ENOMEM;
	346	goto fail_alloc_txq;
	347	}
	348	mbox->txq = mq;
	349
	350	mq = mbox_queue_alloc(mbox, mbox_rxq_fn, mbox_rx_work);
	351	if (!mq) {
	352	ret = -ENOMEM;
	353	goto fail_alloc_rxq;
	354	}
	355	mbox->rxq = mq;
	356
	357	return 0;
	358
	359	fail_alloc_rxq:
	360	mbox_queue_free(mbox->txq);
	361	fail_alloc_txq:
	362	free_irq(mbox->irq, mbox);
	363	fail_request_irq:
340a614a HD	364	if (unlikely(mbox->ops->shutdown))
	365	mbox->ops->shutdown(mbox);
	366
	367	return ret;
	368	}
	369
	370	static void omap_mbox_fini(struct omap_mbox *mbox)
	371	{
	372	mbox_queue_free(mbox->txq);
	373	mbox_queue_free(mbox->rxq);
	374
	375	free_irq(mbox->irq, mbox);
340a614a HD	376
	377	if (unlikely(mbox->ops->shutdown))
	378	mbox->ops->shutdown(mbox);
	379	}
	380
	381	static struct omap_mbox *find_mboxes(const char name)
	382	{
	383	struct omap_mbox **p;
	384
	385	for (p = &mboxes; p; p = &(p)->next) {
	386	if (strcmp((*p)->name, name) == 0)
	387	break;
	388	}
	389
	390	return p;
	391	}
	392
	393	struct omap_mbox omap_mbox_get(const char name)
	394	{
	395	struct omap_mbox *mbox;
	396	int ret;
	397
	398	read_lock(&mboxes_lock);
	399	mbox = *(find_mboxes(name));
	400	if (mbox == NULL) {
	401	read_unlock(&mboxes_lock);
	402	return ERR_PTR(-ENOENT);
	403	}
	404
	405	read_unlock(&mboxes_lock);
	406
	407	ret = omap_mbox_init(mbox);
	408	if (ret)
	409	return ERR_PTR(-ENODEV);
	410
	411	return mbox;
	412	}
	413	EXPORT_SYMBOL(omap_mbox_get);
	414
	415	void omap_mbox_put(struct omap_mbox *mbox)
	416	{
	417	omap_mbox_fini(mbox);
	418	}
	419	EXPORT_SYMBOL(omap_mbox_put);
	420
f48cca87	421	int omap_mbox_register(struct device parent, struct omap_mbox mbox)
340a614a HD	422	{
	423	int ret = 0;
	424	struct omap_mbox **tmp;
	425
	426	if (!mbox)
	427	return -EINVAL;
	428	if (mbox->next)
	429	return -EBUSY;
	430
f48cca87 HD	431	mbox->dev = device_create(&omap_mbox_class,
	432	parent, 0, mbox, "%s", mbox->name);
	433	if (IS_ERR(mbox->dev))
	434	return PTR_ERR(mbox->dev);
	435
	436	ret = device_create_file(mbox->dev, &dev_attr_mbox);
	437	if (ret)
	438	goto err_sysfs;
	439
340a614a HD	440	write_lock(&mboxes_lock);
340a614a HD	441	tmp = find_mboxes(mbox->name);
f48cca87	442	if (*tmp) {
340a614a	443	ret = -EBUSY;
f48cca87 HD	444	write_unlock(&mboxes_lock);
	445	goto err_find;
	446	}
	447	*tmp = mbox;
340a614a HD	448	write_unlock(&mboxes_lock);
340a614a HD	449
f48cca87 HD	450	return 0;
	451
	452	err_find:
	453	device_remove_file(mbox->dev, &dev_attr_mbox);
	454	err_sysfs:
	455	device_unregister(mbox->dev);
340a614a HD	456	return ret;
	457	}
	458	EXPORT_SYMBOL(omap_mbox_register);
	459
	460	int omap_mbox_unregister(struct omap_mbox *mbox)
	461	{
	462	struct omap_mbox **tmp;
	463
	464	write_lock(&mboxes_lock);
	465	tmp = &mboxes;
	466	while (*tmp) {
	467	if (mbox == *tmp) {
	468	*tmp = mbox->next;
	469	mbox->next = NULL;
	470	write_unlock(&mboxes_lock);
f48cca87 HD	471	device_remove_file(mbox->dev, &dev_attr_mbox);
f48cca87 HD	472	device_unregister(mbox->dev);
340a614a HD	473	return 0;
	474	}
	475	tmp = &(*tmp)->next;
	476	}
	477	write_unlock(&mboxes_lock);
	478
	479	return -EINVAL;
	480	}
	481	EXPORT_SYMBOL(omap_mbox_unregister);
	482
	483	static int __init omap_mbox_class_init(void)
	484	{
	485	int ret = class_register(&omap_mbox_class);
	486	if (!ret)
	487	ret = class_create_file(&omap_mbox_class, &class_attr_mbox);
	488
	489	return ret;
	490	}
	491
	492	static void __exit omap_mbox_class_exit(void)
	493	{
	494	class_remove_file(&omap_mbox_class, &class_attr_mbox);
	495	class_unregister(&omap_mbox_class);
	496	}
	497
	498	subsys_initcall(omap_mbox_class_init);
	499	module_exit(omap_mbox_class_exit);
	500
f48cca87 HD	501	MODULE_LICENSE("GPL v2");
	502	MODULE_DESCRIPTION("omap mailbox: interrupt driven messaging");
	503	MODULE_AUTHOR("Toshihiro Kobayashi and Hiroshi DOYU");