422 строки
8.3 KiB
C
422 строки
8.3 KiB
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 workqueue_struct *mboxd;
|
|
static struct omap_mbox *mboxes;
|
|
static DEFINE_RWLOCK(mboxes_lock);
|
|
|
|
static int mbox_configured;
|
|
|
|
/* 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_msg_send(struct omap_mbox *mbox, mbox_msg_t msg)
|
|
{
|
|
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);
|
|
}
|
|
mbox_fifo_write(mbox, msg);
|
|
return ret;
|
|
}
|
|
|
|
|
|
int omap_mbox_msg_send(struct omap_mbox *mbox, mbox_msg_t msg)
|
|
{
|
|
|
|
struct request *rq;
|
|
struct request_queue *q = mbox->txq->queue;
|
|
|
|
rq = blk_get_request(q, WRITE, GFP_ATOMIC);
|
|
if (unlikely(!rq))
|
|
return -ENOMEM;
|
|
|
|
blk_insert_request(q, rq, 0, (void *) msg);
|
|
tasklet_schedule(&mbox->txq->tasklet);
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(omap_mbox_msg_send);
|
|
|
|
static void mbox_tx_tasklet(unsigned long tx_data)
|
|
{
|
|
int ret;
|
|
struct request *rq;
|
|
struct omap_mbox *mbox = (struct omap_mbox *)tx_data;
|
|
struct request_queue *q = mbox->txq->queue;
|
|
|
|
while (1) {
|
|
|
|
rq = blk_fetch_request(q);
|
|
|
|
if (!rq)
|
|
break;
|
|
|
|
ret = __mbox_msg_send(mbox, (mbox_msg_t)rq->special);
|
|
if (ret) {
|
|
omap_mbox_enable_irq(mbox, IRQ_TX);
|
|
blk_requeue_request(q, rq);
|
|
return;
|
|
}
|
|
blk_end_request_all(rq, 0);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* 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;
|
|
|
|
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)
|
|
{
|
|
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 request *rq;
|
|
mbox_msg_t msg;
|
|
struct request_queue *q = mbox->rxq->queue;
|
|
|
|
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);
|
|
nomem:
|
|
queue_work(mboxd, &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,
|
|
request_fn_proc *proc,
|
|
void (*work) (struct work_struct *),
|
|
void (*tasklet)(unsigned long))
|
|
{
|
|
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;
|
|
|
|
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)
|
|
{
|
|
blk_cleanup_queue(q->queue);
|
|
kfree(q);
|
|
}
|
|
|
|
static int omap_mbox_startup(struct omap_mbox *mbox)
|
|
{
|
|
int ret = 0;
|
|
struct omap_mbox_queue *mq;
|
|
|
|
if (likely(mbox->ops->startup)) {
|
|
write_lock(&mboxes_lock);
|
|
if (!mbox_configured)
|
|
ret = mbox->ops->startup(mbox);
|
|
|
|
if (unlikely(ret)) {
|
|
write_unlock(&mboxes_lock);
|
|
return ret;
|
|
}
|
|
mbox_configured++;
|
|
write_unlock(&mboxes_lock);
|
|
}
|
|
|
|
ret = request_irq(mbox->irq, mbox_interrupt, IRQF_SHARED,
|
|
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, NULL, mbox_tx_tasklet);
|
|
if (!mq) {
|
|
ret = -ENOMEM;
|
|
goto fail_alloc_txq;
|
|
}
|
|
mbox->txq = mq;
|
|
|
|
mq = mbox_queue_alloc(mbox, mbox_rxq_fn, mbox_rx_work, NULL);
|
|
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)) {
|
|
write_lock(&mboxes_lock);
|
|
if (mbox_configured > 0)
|
|
mbox_configured--;
|
|
if (!mbox_configured)
|
|
mbox->ops->shutdown(mbox);
|
|
write_unlock(&mboxes_lock);
|
|
}
|
|
}
|
|
|
|
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_startup(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;
|
|
|
|
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:
|
|
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);
|
|
return 0;
|
|
}
|
|
tmp = &(*tmp)->next;
|
|
}
|
|
write_unlock(&mboxes_lock);
|
|
|
|
return -EINVAL;
|
|
}
|
|
EXPORT_SYMBOL(omap_mbox_unregister);
|
|
|
|
static int __init omap_mbox_init(void)
|
|
{
|
|
mboxd = create_workqueue("mboxd");
|
|
if (!mboxd)
|
|
return -ENOMEM;
|
|
|
|
return 0;
|
|
}
|
|
module_init(omap_mbox_init);
|
|
|
|
static void __exit omap_mbox_exit(void)
|
|
{
|
|
destroy_workqueue(mboxd);
|
|
}
|
|
module_exit(omap_mbox_exit);
|
|
|
|
MODULE_LICENSE("GPL v2");
|
|
MODULE_DESCRIPTION("omap mailbox: interrupt driven messaging");
|
|
MODULE_AUTHOR("Toshihiro Kobayashi and Hiroshi DOYU");
|