[mirror_ubuntu-artful-kernel.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/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
 */
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_fifo_full(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_fifo_full(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));
	}

	/* 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>
5a0e3ad6	27	#include <linux/slab.h>
b5bebe41 OBC	28	#include <linux/kfifo.h>
b5bebe41 OBC	29	#include <linux/err.h>
58256307	30	#include <linux/notifier.h>
73017a54	31	#include <linux/module.h>
8dff0fa5	32
c869c75c	33	#include "omap-mbox.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	*/
b2b6362e	76	int omap_mbox_msg_send(struct omap_mbox *mbox, mbox_msg_t msg)
340a614a	77	{
b5bebe41 OBC	78	struct omap_mbox_queue *mq = mbox->txq;
b5bebe41 OBC	79	int ret = 0, len;
5ed8d32e	80
a42743c2	81	spin_lock_bh(&mq->lock);
ec24751a	82
b5bebe41 OBC	83	if (kfifo_avail(&mq->fifo) < sizeof(msg)) {
	84	ret = -ENOMEM;
	85	goto out;
	86	}
	87
fe714a46	88	if (kfifo_is_empty(&mq->fifo) && !mbox_fifo_full(mbox)) {
a42743c2 KH	89	mbox_fifo_write(mbox, msg);
	90	goto out;
	91	}
	92
b5bebe41 OBC	93	len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
b5bebe41 OBC	94	WARN_ON(len != sizeof(msg));
340a614a	95
5ed8d32e	96	tasklet_schedule(&mbox->txq->tasklet);
340a614a	97
b5bebe41	98	out:
a42743c2	99	spin_unlock_bh(&mq->lock);
b5bebe41	100	return ret;
340a614a HD	101	}
	102	EXPORT_SYMBOL(omap_mbox_msg_send);
	103
c869c75c SA	104	void omap_mbox_save_ctx(struct omap_mbox *mbox)
	105	{
	106	if (!mbox->ops->save_ctx) {
	107	dev_err(mbox->dev, "%s:\tno save\n", __func__);
	108	return;
	109	}
	110
	111	mbox->ops->save_ctx(mbox);
	112	}
	113	EXPORT_SYMBOL(omap_mbox_save_ctx);
	114
	115	void omap_mbox_restore_ctx(struct omap_mbox *mbox)
	116	{
	117	if (!mbox->ops->restore_ctx) {
	118	dev_err(mbox->dev, "%s:\tno restore\n", __func__);
	119	return;
	120	}
	121
	122	mbox->ops->restore_ctx(mbox);
	123	}
	124	EXPORT_SYMBOL(omap_mbox_restore_ctx);
	125
	126	void omap_mbox_enable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
	127	{
	128	mbox->ops->enable_irq(mbox, irq);
	129	}
	130	EXPORT_SYMBOL(omap_mbox_enable_irq);
	131
	132	void omap_mbox_disable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
	133	{
	134	mbox->ops->disable_irq(mbox, irq);
	135	}
	136	EXPORT_SYMBOL(omap_mbox_disable_irq);
	137
5ed8d32e	138	static void mbox_tx_tasklet(unsigned long tx_data)
340a614a	139	{
5ed8d32e	140	struct omap_mbox mbox = (struct omap_mbox )tx_data;
b5bebe41 OBC	141	struct omap_mbox_queue *mq = mbox->txq;
	142	mbox_msg_t msg;
	143	int ret;
340a614a	144
b5bebe41	145	while (kfifo_len(&mq->fifo)) {
fe714a46	146	if (mbox_fifo_full(mbox)) {
eb18858e	147	omap_mbox_enable_irq(mbox, IRQ_TX);
b5bebe41	148	break;
340a614a	149	}
b5bebe41 OBC	150
	151	ret = kfifo_out(&mq->fifo, (unsigned char *)&msg,
	152	sizeof(msg));
	153	WARN_ON(ret != sizeof(msg));
	154
	155	mbox_fifo_write(mbox, msg);
340a614a HD	156	}
	157	}
	158
	159	/*
	160	* Message receiver(workqueue)
	161	*/
	162	static void mbox_rx_work(struct work_struct *work)
	163	{
	164	struct omap_mbox_queue *mq =
	165	container_of(work, struct omap_mbox_queue, work);
340a614a	166	mbox_msg_t msg;
b5bebe41 OBC	167	int len;
	168
	169	while (kfifo_len(&mq->fifo) >= sizeof(msg)) {
	170	len = kfifo_out(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
	171	WARN_ON(len != sizeof(msg));
340a614a	172
58256307 KH	173	blocking_notifier_call_chain(&mq->mbox->notifier, len,
58256307 KH	174	(void *)msg);
d2295042 FGL	175	spin_lock_irq(&mq->lock);
	176	if (mq->full) {
	177	mq->full = false;
	178	omap_mbox_enable_irq(mq->mbox, IRQ_RX);
	179	}
	180	spin_unlock_irq(&mq->lock);
340a614a HD	181	}
	182	}
	183
	184	/*
	185	* Mailbox interrupt handler
	186	*/
340a614a HD	187	static void __mbox_tx_interrupt(struct omap_mbox *mbox)
340a614a HD	188	{
eb18858e	189	omap_mbox_disable_irq(mbox, IRQ_TX);
340a614a	190	ack_mbox_irq(mbox, IRQ_TX);
5ed8d32e	191	tasklet_schedule(&mbox->txq->tasklet);
340a614a HD	192	}
	193
	194	static void __mbox_rx_interrupt(struct omap_mbox *mbox)
	195	{
b5bebe41	196	struct omap_mbox_queue *mq = mbox->rxq;
340a614a	197	mbox_msg_t msg;
b5bebe41	198	int len;
340a614a	199
340a614a	200	while (!mbox_fifo_empty(mbox)) {
b5bebe41	201	if (unlikely(kfifo_avail(&mq->fifo) < sizeof(msg))) {
1ea5d6d1	202	omap_mbox_disable_irq(mbox, IRQ_RX);
d2295042	203	mq->full = true;
340a614a	204	goto nomem;
1ea5d6d1	205	}
340a614a HD	206
340a614a HD	207	msg = mbox_fifo_read(mbox);
340a614a	208
b5bebe41 OBC	209	len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
b5bebe41 OBC	210	WARN_ON(len != sizeof(msg));
340a614a HD	211	}
	212
	213	/* no more messages in the fifo. clear IRQ source. */
	214	ack_mbox_irq(mbox, IRQ_RX);
f48cca87	215	nomem:
c4873005	216	schedule_work(&mbox->rxq->work);
340a614a HD	217	}
	218
	219	static irqreturn_t mbox_interrupt(int irq, void *p)
	220	{
2a7057e3	221	struct omap_mbox *mbox = p;
340a614a HD	222
	223	if (is_mbox_irq(mbox, IRQ_TX))
	224	__mbox_tx_interrupt(mbox);
	225
	226	if (is_mbox_irq(mbox, IRQ_RX))
	227	__mbox_rx_interrupt(mbox);
	228
	229	return IRQ_HANDLED;
	230	}
	231
340a614a	232	static struct omap_mbox_queue mbox_queue_alloc(struct omap_mbox mbox,
5ed8d32e S	233	void (work) (struct work_struct ),
5ed8d32e S	234	void (*tasklet)(unsigned long))
340a614a	235	{
340a614a HD	236	struct omap_mbox_queue *mq;
	237
	238	mq = kzalloc(sizeof(struct omap_mbox_queue), GFP_KERNEL);
	239	if (!mq)
	240	return NULL;
	241
	242	spin_lock_init(&mq->lock);
	243
b5bebe41	244	if (kfifo_alloc(&mq->fifo, mbox_kfifo_size, GFP_KERNEL))
340a614a	245	goto error;
340a614a	246
5ed8d32e S	247	if (work)
5ed8d32e S	248	INIT_WORK(&mq->work, work);
340a614a	249
5ed8d32e S	250	if (tasklet)
5ed8d32e S	251	tasklet_init(&mq->tasklet, tasklet, (unsigned long)mbox);
340a614a HD	252	return mq;
	253	error:
	254	kfree(mq);
	255	return NULL;
	256	}
	257
	258	static void mbox_queue_free(struct omap_mbox_queue *q)
	259	{
b5bebe41	260	kfifo_free(&q->fifo);
340a614a HD	261	kfree(q);
	262	}
	263
c7c158e5	264	static int omap_mbox_startup(struct omap_mbox *mbox)
340a614a	265	{
5f00ec64	266	int ret = 0;
340a614a HD	267	struct omap_mbox_queue *mq;
340a614a HD	268
58256307 KH	269	mutex_lock(&mbox_configured_lock);
	270	if (!mbox_configured++) {
	271	if (likely(mbox->ops->startup)) {
5f00ec64	272	ret = mbox->ops->startup(mbox);
58256307 KH	273	if (unlikely(ret))
	274	goto fail_startup;
	275	} else
	276	goto fail_startup;
340a614a HD	277	}
340a614a HD	278
58256307	279	if (!mbox->use_count++) {
58256307 KH	280	mq = mbox_queue_alloc(mbox, NULL, mbox_tx_tasklet);
	281	if (!mq) {
	282	ret = -ENOMEM;
	283	goto fail_alloc_txq;
	284	}
	285	mbox->txq = mq;
340a614a	286
58256307 KH	287	mq = mbox_queue_alloc(mbox, mbox_rx_work, NULL);
	288	if (!mq) {
	289	ret = -ENOMEM;
	290	goto fail_alloc_rxq;
	291	}
	292	mbox->rxq = mq;
	293	mq->mbox = mbox;
ecf305cf SA	294	ret = request_irq(mbox->irq, mbox_interrupt, IRQF_SHARED,
	295	mbox->name, mbox);
	296	if (unlikely(ret)) {
	297	pr_err("failed to register mailbox interrupt:%d\n",
	298	ret);
	299	goto fail_request_irq;
	300	}
1d8a0e96 JG	301
1d8a0e96 JG	302	omap_mbox_enable_irq(mbox, IRQ_RX);
340a614a	303	}
58256307	304	mutex_unlock(&mbox_configured_lock);
340a614a HD	305	return 0;
340a614a HD	306
ecf305cf SA	307	fail_request_irq:
ecf305cf SA	308	mbox_queue_free(mbox->rxq);
ab66ac30	309	fail_alloc_rxq:
340a614a	310	mbox_queue_free(mbox->txq);
ab66ac30	311	fail_alloc_txq:
01072d8f	312	if (mbox->ops->shutdown)
340a614a	313	mbox->ops->shutdown(mbox);
58256307 KH	314	mbox->use_count--;
	315	fail_startup:
	316	mbox_configured--;
	317	mutex_unlock(&mbox_configured_lock);
340a614a HD	318	return ret;
	319	}
	320
	321	static void omap_mbox_fini(struct omap_mbox *mbox)
	322	{
58256307 KH	323	mutex_lock(&mbox_configured_lock);
	324
	325	if (!--mbox->use_count) {
1d8a0e96	326	omap_mbox_disable_irq(mbox, IRQ_RX);
58256307 KH	327	free_irq(mbox->irq, mbox);
58256307 KH	328	tasklet_kill(&mbox->txq->tasklet);
43829731	329	flush_work(&mbox->rxq->work);
58256307 KH	330	mbox_queue_free(mbox->txq);
	331	mbox_queue_free(mbox->rxq);
	332	}
340a614a	333
58256307 KH	334	if (likely(mbox->ops->shutdown)) {
58256307 KH	335	if (!--mbox_configured)
5f00ec64	336	mbox->ops->shutdown(mbox);
5f00ec64	337	}
58256307 KH	338
58256307 KH	339	mutex_unlock(&mbox_configured_lock);
340a614a HD	340	}
340a614a HD	341
58256307	342	struct omap_mbox omap_mbox_get(const char name, struct notifier_block *nb)
340a614a	343	{
c0377320 KH	344	struct omap_mbox _mbox, mbox = NULL;
c0377320 KH	345	int i, ret;
340a614a	346
9c80c8cd FC	347	if (!mboxes)
9c80c8cd FC	348	return ERR_PTR(-EINVAL);
340a614a	349
c0377320 KH	350	for (i = 0; (_mbox = mboxes[i]); i++) {
	351	if (!strcmp(_mbox->name, name)) {
	352	mbox = _mbox;
9c80c8cd	353	break;
c0377320 KH	354	}
c0377320 KH	355	}
9c80c8cd FC	356
	357	if (!mbox)
	358	return ERR_PTR(-ENOENT);
340a614a	359
58256307 KH	360	if (nb)
	361	blocking_notifier_chain_register(&mbox->notifier, nb);
	362
1d8a0e96 JG	363	ret = omap_mbox_startup(mbox);
	364	if (ret) {
	365	blocking_notifier_chain_unregister(&mbox->notifier, nb);
	366	return ERR_PTR(-ENODEV);
	367	}
	368
340a614a HD	369	return mbox;
	370	}
	371	EXPORT_SYMBOL(omap_mbox_get);
	372
58256307	373	void omap_mbox_put(struct omap_mbox mbox, struct notifier_block nb)
340a614a	374	{
58256307	375	blocking_notifier_chain_unregister(&mbox->notifier, nb);
340a614a HD	376	omap_mbox_fini(mbox);
	377	}
	378	EXPORT_SYMBOL(omap_mbox_put);
	379
6b233985 HD	380	static struct class omap_mbox_class = { .name = "mbox", };
6b233985 HD	381
9c80c8cd	382	int omap_mbox_register(struct device parent, struct omap_mbox *list)
340a614a	383	{
9c80c8cd FC	384	int ret;
9c80c8cd FC	385	int i;
340a614a	386
9c80c8cd FC	387	mboxes = list;
9c80c8cd FC	388	if (!mboxes)
340a614a	389	return -EINVAL;
340a614a	390
9c80c8cd FC	391	for (i = 0; mboxes[i]; i++) {
	392	struct omap_mbox *mbox = mboxes[i];
	393	mbox->dev = device_create(&omap_mbox_class,
	394	parent, 0, mbox, "%s", mbox->name);
	395	if (IS_ERR(mbox->dev)) {
	396	ret = PTR_ERR(mbox->dev);
	397	goto err_out;
	398	}
58256307 KH	399
58256307 KH	400	BLOCKING_INIT_NOTIFIER_HEAD(&mbox->notifier);
9c80c8cd	401	}
f48cca87 HD	402	return 0;
f48cca87 HD	403
9c80c8cd FC	404	err_out:
	405	while (i--)
	406	device_unregister(mboxes[i]->dev);
340a614a HD	407	return ret;
	408	}
	409	EXPORT_SYMBOL(omap_mbox_register);
	410
9c80c8cd	411	int omap_mbox_unregister(void)
340a614a	412	{
9c80c8cd	413	int i;
340a614a	414
9c80c8cd FC	415	if (!mboxes)
	416	return -EINVAL;
	417
	418	for (i = 0; mboxes[i]; i++)
	419	device_unregister(mboxes[i]->dev);
	420	mboxes = NULL;
	421	return 0;
340a614a HD	422	}
	423	EXPORT_SYMBOL(omap_mbox_unregister);
	424
c7c158e5	425	static int __init omap_mbox_init(void)
340a614a	426	{
6b233985 HD	427	int err;
	428
	429	err = class_register(&omap_mbox_class);
	430	if (err)
	431	return err;
	432
b5bebe41 OBC	433	/* kfifo size sanity check: alignment and minimal size */
b5bebe41 OBC	434	mbox_kfifo_size = ALIGN(mbox_kfifo_size, sizeof(mbox_msg_t));
ab66ac30 KH	435	mbox_kfifo_size = max_t(unsigned int, mbox_kfifo_size,
ab66ac30 KH	436	sizeof(mbox_msg_t));
b5bebe41	437
c7c158e5	438	return 0;
340a614a	439	}
6b233985	440	subsys_initcall(omap_mbox_init);
340a614a	441
c7c158e5	442	static void __exit omap_mbox_exit(void)
340a614a	443	{
6b233985	444	class_unregister(&omap_mbox_class);
340a614a	445	}
c7c158e5	446	module_exit(omap_mbox_exit);
340a614a	447
f48cca87 HD	448	MODULE_LICENSE("GPL v2");
f48cca87 HD	449	MODULE_DESCRIPTION("omap mailbox: interrupt driven messaging");
f375325a OBC	450	MODULE_AUTHOR("Toshihiro Kobayashi");
f375325a OBC	451	MODULE_AUTHOR("Hiroshi DOYU");