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

#include <plat/mailbox.h>

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

/* 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 enable_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
{
	mbox->ops->enable_irq(mbox, irq);
}
static inline void disable_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
{
	mbox->ops->disable_irq(mbox, irq);
}
static inline void ack_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
{
	if (mbox->ops->ack_irq)
		mbox->ops->ack_irq(mbox, irq);
}
static inline int is_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
{
	return mbox->ops->is_irq(mbox, irq);
}

/*
 * message sender
 */
static int __mbox_msg_send(struct omap_mbox *mbox, mbox_msg_t msg, 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_fifo_write(mbox, msg);
 out:
	return ret;
}

struct omap_msg_tx_data {
	mbox_msg_t	msg;
	void		*arg;
};

static void omap_msg_tx_end_io(struct request *rq, int error)
{
	kfree(rq->special);
	__blk_put_request(rq->q, rq);
}

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

	tx_data = kmalloc(sizeof(*tx_data), GFP_ATOMIC);
	if (unlikely(!tx_data))
		return -ENOMEM;

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

	tx_data->msg = msg;
	tx_data->arg = arg;
	rq->end_io = omap_msg_tx_end_io;
	blk_insert_request(q, rq, 0, tx_data);

	schedule_work(&mbox->txq->work);
	return 0;
}
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) {
		struct omap_msg_tx_data *tx_data;

		spin_lock(q->queue_lock);
		rq = blk_fetch_request(q);
		spin_unlock(q->queue_lock);

		if (!rq)
			break;

		tx_data = rq->special;

		ret = __mbox_msg_send(mbox, tx_data->msg, tx_data->arg);
		if (ret) {
			enable_mbox_irq(mbox, IRQ_TX);
			spin_lock(q->queue_lock);
			blk_requeue_request(q, rq);
			spin_unlock(q->queue_lock);
			return;
		}

		spin_lock(q->queue_lock);
		__blk_end_request_all(rq, 0);
		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 = blk_fetch_request(q);
		spin_unlock_irqrestore(q->queue_lock, flags);
		if (!rq)
			break;

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

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

static void mbox_rxq_fn(struct request_queue *q)
{
}

static void __mbox_tx_interrupt(struct omap_mbox *mbox)
{
	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);


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

	/* no more messages in the fifo. clear IRQ source. */
	ack_mbox_irq(mbox, IRQ_RX);
	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 = blk_fetch_request(q);
		spin_unlock_irqrestore(q->queue_lock, flags);

		if (!rq)
			break;

		*p = (mbox_msg_t)rq->special;

		blk_end_request_all(rq, 0);

		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
340a614a	24	#include <linux/module.h>
340a614a HD	25	#include <linux/interrupt.h>
340a614a HD	26	#include <linux/device.h>
340a614a	27	#include <linux/delay.h>
8dff0fa5	28
ce491cf8	29	#include <plat/mailbox.h>
340a614a HD	30
	31	static struct omap_mbox *mboxes;
	32	static DEFINE_RWLOCK(mboxes_lock);
	33
9ae0ee00 HD	34	/* Mailbox FIFO handle functions */
	35	static inline mbox_msg_t mbox_fifo_read(struct omap_mbox *mbox)
	36	{
	37	return mbox->ops->fifo_read(mbox);
	38	}
	39	static inline void mbox_fifo_write(struct omap_mbox *mbox, mbox_msg_t msg)
	40	{
	41	mbox->ops->fifo_write(mbox, msg);
	42	}
	43	static inline int mbox_fifo_empty(struct omap_mbox *mbox)
	44	{
	45	return mbox->ops->fifo_empty(mbox);
	46	}
	47	static inline int mbox_fifo_full(struct omap_mbox *mbox)
	48	{
	49	return mbox->ops->fifo_full(mbox);
	50	}
	51
	52	/* Mailbox IRQ handle functions */
	53	static inline void enable_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
	54	{
	55	mbox->ops->enable_irq(mbox, irq);
	56	}
	57	static inline void disable_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
	58	{
	59	mbox->ops->disable_irq(mbox, irq);
	60	}
	61	static inline void ack_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
	62	{
	63	if (mbox->ops->ack_irq)
	64	mbox->ops->ack_irq(mbox, irq);
	65	}
	66	static inline int is_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
	67	{
	68	return mbox->ops->is_irq(mbox, irq);
	69	}
	70
340a614a HD	71	/*
	72	* message sender
	73	*/
	74	static int __mbox_msg_send(struct omap_mbox mbox, mbox_msg_t msg, void arg)
	75	{
	76	int ret = 0, i = 1000;
	77
	78	while (mbox_fifo_full(mbox)) {
	79	if (mbox->ops->type == OMAP_MBOX_TYPE2)
	80	return -1;
	81	if (--i == 0)
	82	return -1;
	83	udelay(1);
	84	}
	85
	86	if (arg && mbox->txq->callback) {
	87	ret = mbox->txq->callback(arg);
	88	if (ret)
	89	goto out;
	90	}
	91
340a614a HD	92	mbox_fifo_write(mbox, msg);
	93	out:
	94	return ret;
	95	}
	96
ec24751a TH	97	struct omap_msg_tx_data {
	98	mbox_msg_t msg;
	99	void *arg;
	100	};
	101
	102	static void omap_msg_tx_end_io(struct request *rq, int error)
	103	{
	104	kfree(rq->special);
	105	__blk_put_request(rq->q, rq);
	106	}
	107
340a614a HD	108	int omap_mbox_msg_send(struct omap_mbox mbox, mbox_msg_t msg, void arg)
340a614a HD	109	{
ec24751a	110	struct omap_msg_tx_data *tx_data;
340a614a HD	111	struct request *rq;
340a614a HD	112	struct request_queue *q = mbox->txq->queue;
ec24751a TH	113
	114	tx_data = kmalloc(sizeof(*tx_data), GFP_ATOMIC);
	115	if (unlikely(!tx_data))
	116	return -ENOMEM;
340a614a HD	117
	118	rq = blk_get_request(q, WRITE, GFP_ATOMIC);
	119	if (unlikely(!rq)) {
ec24751a TH	120	kfree(tx_data);
ec24751a TH	121	return -ENOMEM;
340a614a HD	122	}
340a614a HD	123
ec24751a TH	124	tx_data->msg = msg;
	125	tx_data->arg = arg;
	126	rq->end_io = omap_msg_tx_end_io;
	127	blk_insert_request(q, rq, 0, tx_data);
340a614a HD	128
340a614a HD	129	schedule_work(&mbox->txq->work);
ec24751a	130	return 0;
340a614a HD	131	}
	132	EXPORT_SYMBOL(omap_mbox_msg_send);
	133
	134	static void mbox_tx_work(struct work_struct *work)
	135	{
	136	int ret;
	137	struct request *rq;
	138	struct omap_mbox_queue *mq = container_of(work,
	139	struct omap_mbox_queue, work);
	140	struct omap_mbox *mbox = mq->queue->queuedata;
	141	struct request_queue *q = mbox->txq->queue;
	142
	143	while (1) {
ec24751a TH	144	struct omap_msg_tx_data *tx_data;
ec24751a TH	145
340a614a	146	spin_lock(q->queue_lock);
9934c8c0	147	rq = blk_fetch_request(q);
340a614a HD	148	spin_unlock(q->queue_lock);
	149
	150	if (!rq)
	151	break;
	152
ec24751a TH	153	tx_data = rq->special;
	154
	155	ret = __mbox_msg_send(mbox, tx_data->msg, tx_data->arg);
340a614a HD	156	if (ret) {
340a614a HD	157	enable_mbox_irq(mbox, IRQ_TX);
296b2f6a TH	158	spin_lock(q->queue_lock);
	159	blk_requeue_request(q, rq);
	160	spin_unlock(q->queue_lock);
340a614a HD	161	return;
	162	}
	163
	164	spin_lock(q->queue_lock);
40cbbb78	165	__blk_end_request_all(rq, 0);
340a614a HD	166	spin_unlock(q->queue_lock);
	167	}
	168	}
	169
	170	/*
	171	* Message receiver(workqueue)
	172	*/
	173	static void mbox_rx_work(struct work_struct *work)
	174	{
	175	struct omap_mbox_queue *mq =
	176	container_of(work, struct omap_mbox_queue, work);
	177	struct omap_mbox *mbox = mq->queue->queuedata;
	178	struct request_queue *q = mbox->rxq->queue;
	179	struct request *rq;
	180	mbox_msg_t msg;
	181	unsigned long flags;
	182
	183	if (mbox->rxq->callback == NULL) {
f48cca87	184	sysfs_notify(&mbox->dev->kobj, NULL, "mbox");
340a614a HD	185	return;
	186	}
	187
	188	while (1) {
	189	spin_lock_irqsave(q->queue_lock, flags);
9934c8c0	190	rq = blk_fetch_request(q);
340a614a HD	191	spin_unlock_irqrestore(q->queue_lock, flags);
	192	if (!rq)
	193	break;
	194
ec24751a	195	msg = (mbox_msg_t)rq->special;
40cbbb78	196	blk_end_request_all(rq, 0);
340a614a HD	197	mbox->rxq->callback((void *)msg);
	198	}
	199	}
	200
	201	/*
	202	* Mailbox interrupt handler
	203	*/
bfe1f6ac	204	static void mbox_txq_fn(struct request_queue *q)
340a614a HD	205	{
	206	}
	207
bfe1f6ac	208	static void mbox_rxq_fn(struct request_queue *q)
340a614a HD	209	{
	210	}
	211
	212	static void __mbox_tx_interrupt(struct omap_mbox *mbox)
	213	{
	214	disable_mbox_irq(mbox, IRQ_TX);
	215	ack_mbox_irq(mbox, IRQ_TX);
	216	schedule_work(&mbox->txq->work);
	217	}
	218
	219	static void __mbox_rx_interrupt(struct omap_mbox *mbox)
	220	{
	221	struct request *rq;
	222	mbox_msg_t msg;
165125e1	223	struct request_queue *q = mbox->rxq->queue;
340a614a HD	224
	225	disable_mbox_irq(mbox, IRQ_RX);
	226
	227	while (!mbox_fifo_empty(mbox)) {
	228	rq = blk_get_request(q, WRITE, GFP_ATOMIC);
	229	if (unlikely(!rq))
	230	goto nomem;
	231
	232	msg = mbox_fifo_read(mbox);
340a614a	233
340a614a	234
ec24751a	235	blk_insert_request(q, rq, 0, (void *)msg);
340a614a HD	236	if (mbox->ops->type == OMAP_MBOX_TYPE1)
	237	break;
	238	}
	239
	240	/* no more messages in the fifo. clear IRQ source. */
	241	ack_mbox_irq(mbox, IRQ_RX);
	242	enable_mbox_irq(mbox, IRQ_RX);
f48cca87	243	nomem:
340a614a HD	244	schedule_work(&mbox->rxq->work);
	245	}
	246
	247	static irqreturn_t mbox_interrupt(int irq, void *p)
	248	{
2a7057e3	249	struct omap_mbox *mbox = p;
340a614a HD	250
	251	if (is_mbox_irq(mbox, IRQ_TX))
	252	__mbox_tx_interrupt(mbox);
	253
	254	if (is_mbox_irq(mbox, IRQ_RX))
	255	__mbox_rx_interrupt(mbox);
	256
	257	return IRQ_HANDLED;
	258	}
	259
	260	/*
	261	* sysfs files
	262	*/
	263	static ssize_t
	264	omap_mbox_write(struct device dev, struct device_attribute attr,
bfe1f6ac	265	const char *buf, size_t count)
340a614a HD	266	{
	267	int ret;
	268	mbox_msg_t p = (mbox_msg_t )buf;
	269	struct omap_mbox *mbox = dev_get_drvdata(dev);
	270
	271	for (; count >= sizeof(mbox_msg_t); count -= sizeof(mbox_msg_t)) {
	272	ret = omap_mbox_msg_send(mbox, be32_to_cpu(*p), NULL);
	273	if (ret)
	274	return -EAGAIN;
	275	p++;
	276	}
	277
	278	return (size_t)((char *)p - buf);
	279	}
	280
	281	static ssize_t
	282	omap_mbox_read(struct device dev, struct device_attribute attr, char *buf)
	283	{
	284	unsigned long flags;
	285	struct request *rq;
	286	mbox_msg_t p = (mbox_msg_t ) buf;
	287	struct omap_mbox *mbox = dev_get_drvdata(dev);
	288	struct request_queue *q = mbox->rxq->queue;
	289
	290	while (1) {
	291	spin_lock_irqsave(q->queue_lock, flags);
9934c8c0	292	rq = blk_fetch_request(q);
340a614a HD	293	spin_unlock_irqrestore(q->queue_lock, flags);
	294
	295	if (!rq)
	296	break;
	297
ec24751a	298	*p = (mbox_msg_t)rq->special;
340a614a	299
40cbbb78	300	blk_end_request_all(rq, 0);
340a614a	301
340a614a HD	302	p++;
	303	}
	304
	305	pr_debug("%02x %02x %02x %02x\n", buf[0], buf[1], buf[2], buf[3]);
	306
	307	return (size_t) ((char *)p - buf);
	308	}
	309
	310	static DEVICE_ATTR(mbox, S_IRUGO \| S_IWUSR, omap_mbox_read, omap_mbox_write);
	311
	312	static ssize_t mbox_show(struct class class, char buf)
	313	{
	314	return sprintf(buf, "mbox");
	315	}
	316
	317	static CLASS_ATTR(mbox, S_IRUGO, mbox_show, NULL);
	318
	319	static struct class omap_mbox_class = {
f48cca87	320	.name = "omap-mailbox",
340a614a HD	321	};
	322
	323	static struct omap_mbox_queue mbox_queue_alloc(struct omap_mbox mbox,
bfe1f6ac	324	request_fn_proc *proc,
340a614a HD	325	void (work) (struct work_struct ))
340a614a HD	326	{
165125e1	327	struct request_queue *q;
340a614a HD	328	struct omap_mbox_queue *mq;
	329
	330	mq = kzalloc(sizeof(struct omap_mbox_queue), GFP_KERNEL);
	331	if (!mq)
	332	return NULL;
	333
	334	spin_lock_init(&mq->lock);
	335
	336	q = blk_init_queue(proc, &mq->lock);
	337	if (!q)
	338	goto error;
	339	q->queuedata = mbox;
	340	mq->queue = q;
	341
	342	INIT_WORK(&mq->work, work);
	343
	344	return mq;
	345	error:
	346	kfree(mq);
	347	return NULL;
	348	}
	349
	350	static void mbox_queue_free(struct omap_mbox_queue *q)
	351	{
	352	blk_cleanup_queue(q->queue);
	353	kfree(q);
	354	}
	355
	356	static int omap_mbox_init(struct omap_mbox *mbox)
	357	{
	358	int ret;
	359	struct omap_mbox_queue *mq;
	360
	361	if (likely(mbox->ops->startup)) {
	362	ret = mbox->ops->startup(mbox);
	363	if (unlikely(ret))
	364	return ret;
	365	}
	366
340a614a HD	367	ret = request_irq(mbox->irq, mbox_interrupt, IRQF_DISABLED,
	368	mbox->name, mbox);
	369	if (unlikely(ret)) {
	370	printk(KERN_ERR
	371	"failed to register mailbox interrupt:%d\n", ret);
	372	goto fail_request_irq;
	373	}
340a614a HD	374
	375	mq = mbox_queue_alloc(mbox, mbox_txq_fn, mbox_tx_work);
	376	if (!mq) {
	377	ret = -ENOMEM;
	378	goto fail_alloc_txq;
	379	}
	380	mbox->txq = mq;
	381
	382	mq = mbox_queue_alloc(mbox, mbox_rxq_fn, mbox_rx_work);
	383	if (!mq) {
	384	ret = -ENOMEM;
	385	goto fail_alloc_rxq;
	386	}
	387	mbox->rxq = mq;
	388
	389	return 0;
	390
	391	fail_alloc_rxq:
	392	mbox_queue_free(mbox->txq);
	393	fail_alloc_txq:
	394	free_irq(mbox->irq, mbox);
	395	fail_request_irq:
340a614a HD	396	if (unlikely(mbox->ops->shutdown))
	397	mbox->ops->shutdown(mbox);
	398
	399	return ret;
	400	}
	401
	402	static void omap_mbox_fini(struct omap_mbox *mbox)
	403	{
	404	mbox_queue_free(mbox->txq);
	405	mbox_queue_free(mbox->rxq);
	406
	407	free_irq(mbox->irq, mbox);
340a614a HD	408
	409	if (unlikely(mbox->ops->shutdown))
	410	mbox->ops->shutdown(mbox);
	411	}
	412
	413	static struct omap_mbox *find_mboxes(const char name)
	414	{
	415	struct omap_mbox **p;
	416
	417	for (p = &mboxes; p; p = &(p)->next) {
	418	if (strcmp((*p)->name, name) == 0)
	419	break;
	420	}
	421
	422	return p;
	423	}
	424
	425	struct omap_mbox omap_mbox_get(const char name)
	426	{
	427	struct omap_mbox *mbox;
	428	int ret;
	429
	430	read_lock(&mboxes_lock);
	431	mbox = *(find_mboxes(name));
	432	if (mbox == NULL) {
	433	read_unlock(&mboxes_lock);
	434	return ERR_PTR(-ENOENT);
	435	}
	436
	437	read_unlock(&mboxes_lock);
	438
	439	ret = omap_mbox_init(mbox);
	440	if (ret)
	441	return ERR_PTR(-ENODEV);
	442
	443	return mbox;
	444	}
	445	EXPORT_SYMBOL(omap_mbox_get);
	446
	447	void omap_mbox_put(struct omap_mbox *mbox)
	448	{
	449	omap_mbox_fini(mbox);
	450	}
	451	EXPORT_SYMBOL(omap_mbox_put);
	452
f48cca87	453	int omap_mbox_register(struct device parent, struct omap_mbox mbox)
340a614a HD	454	{
	455	int ret = 0;
	456	struct omap_mbox **tmp;
	457
	458	if (!mbox)
	459	return -EINVAL;
	460	if (mbox->next)
	461	return -EBUSY;
	462
f48cca87 HD	463	mbox->dev = device_create(&omap_mbox_class,
	464	parent, 0, mbox, "%s", mbox->name);
	465	if (IS_ERR(mbox->dev))
	466	return PTR_ERR(mbox->dev);
	467
	468	ret = device_create_file(mbox->dev, &dev_attr_mbox);
	469	if (ret)
	470	goto err_sysfs;
	471
340a614a HD	472	write_lock(&mboxes_lock);
340a614a HD	473	tmp = find_mboxes(mbox->name);
f48cca87	474	if (*tmp) {
340a614a	475	ret = -EBUSY;
f48cca87 HD	476	write_unlock(&mboxes_lock);
	477	goto err_find;
	478	}
	479	*tmp = mbox;
340a614a HD	480	write_unlock(&mboxes_lock);
340a614a HD	481
f48cca87 HD	482	return 0;
	483
	484	err_find:
	485	device_remove_file(mbox->dev, &dev_attr_mbox);
	486	err_sysfs:
	487	device_unregister(mbox->dev);
340a614a HD	488	return ret;
	489	}
	490	EXPORT_SYMBOL(omap_mbox_register);
	491
	492	int omap_mbox_unregister(struct omap_mbox *mbox)
	493	{
	494	struct omap_mbox **tmp;
	495
	496	write_lock(&mboxes_lock);
	497	tmp = &mboxes;
	498	while (*tmp) {
	499	if (mbox == *tmp) {
	500	*tmp = mbox->next;
	501	mbox->next = NULL;
	502	write_unlock(&mboxes_lock);
f48cca87 HD	503	device_remove_file(mbox->dev, &dev_attr_mbox);
f48cca87 HD	504	device_unregister(mbox->dev);
340a614a HD	505	return 0;
	506	}
	507	tmp = &(*tmp)->next;
	508	}
	509	write_unlock(&mboxes_lock);
	510
	511	return -EINVAL;
	512	}
	513	EXPORT_SYMBOL(omap_mbox_unregister);
	514
	515	static int __init omap_mbox_class_init(void)
	516	{
	517	int ret = class_register(&omap_mbox_class);
	518	if (!ret)
	519	ret = class_create_file(&omap_mbox_class, &class_attr_mbox);
	520
	521	return ret;
	522	}
	523
	524	static void __exit omap_mbox_class_exit(void)
	525	{
	526	class_remove_file(&omap_mbox_class, &class_attr_mbox);
	527	class_unregister(&omap_mbox_class);
	528	}
	529
	530	subsys_initcall(omap_mbox_class_init);
	531	module_exit(omap_mbox_class_exit);
	532
f48cca87 HD	533	MODULE_LICENSE("GPL v2");
	534	MODULE_DESCRIPTION("omap mailbox: interrupt driven messaging");
	535	MODULE_AUTHOR("Toshihiro Kobayashi and Hiroshi DOYU");