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Diffstat (limited to 'arch/arm/plat-omap/mailbox.c')
-rw-r--r--arch/arm/plat-omap/mailbox.c248
1 files changed, 118 insertions, 130 deletions
diff --git a/arch/arm/plat-omap/mailbox.c b/arch/arm/plat-omap/mailbox.c
index 08a2df76628..d2fafb892f7 100644
--- a/arch/arm/plat-omap/mailbox.c
+++ b/arch/arm/plat-omap/mailbox.c
@@ -21,19 +21,26 @@
*
*/
-#include <linux/module.h>
#include <linux/interrupt.h>
-#include <linux/device.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 <plat/mailbox.h>
static struct workqueue_struct *mboxd;
-static struct omap_mbox *mboxes;
-static DEFINE_RWLOCK(mboxes_lock);
+static struct omap_mbox **mboxes;
+static bool rq_full;
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)
@@ -67,7 +74,7 @@ static inline int is_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
/*
* message sender
*/
-static int __mbox_msg_send(struct omap_mbox *mbox, mbox_msg_t msg)
+static int __mbox_poll_for_space(struct omap_mbox *mbox)
{
int ret = 0, i = 1000;
@@ -78,49 +85,50 @@ static int __mbox_msg_send(struct omap_mbox *mbox, mbox_msg_t msg)
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 omap_mbox_queue *mq = mbox->txq;
+ int ret = 0, len;
- struct request *rq;
- struct request_queue *q = mbox->txq->queue;
+ spin_lock(&mq->lock);
- rq = blk_get_request(q, WRITE, GFP_ATOMIC);
- if (unlikely(!rq))
- return -ENOMEM;
+ if (kfifo_avail(&mq->fifo) < sizeof(msg)) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
+ WARN_ON(len != sizeof(msg));
- blk_insert_request(q, rq, 0, (void *) msg);
tasklet_schedule(&mbox->txq->tasklet);
- return 0;
+out:
+ spin_unlock(&mq->lock);
+ return ret;
}
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;
+ struct omap_mbox_queue *mq = mbox->txq;
+ mbox_msg_t msg;
+ int ret;
- ret = __mbox_msg_send(mbox, (mbox_msg_t)rq->special);
- if (ret) {
+ while (kfifo_len(&mq->fifo)) {
+ if (__mbox_poll_for_space(mbox)) {
omap_mbox_enable_irq(mbox, IRQ_TX);
- blk_requeue_request(q, rq);
- return;
+ break;
}
- blk_end_request_all(rq, 0);
+
+ ret = kfifo_out(&mq->fifo, (unsigned char *)&msg,
+ sizeof(msg));
+ WARN_ON(ret != sizeof(msg));
+
+ mbox_fifo_write(mbox, msg);
}
}
@@ -131,36 +139,21 @@ 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;
+ int len;
- while (1) {
- spin_lock_irqsave(q->queue_lock, flags);
- rq = blk_fetch_request(q);
- spin_unlock_irqrestore(q->queue_lock, flags);
- if (!rq)
- break;
+ while (kfifo_len(&mq->fifo) >= sizeof(msg)) {
+ len = kfifo_out(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
+ WARN_ON(len != sizeof(msg));
- msg = (mbox_msg_t)rq->special;
- blk_end_request_all(rq, 0);
- mbox->rxq->callback((void *)msg);
+ if (mq->callback)
+ mq->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);
@@ -170,19 +163,22 @@ static void __mbox_tx_interrupt(struct omap_mbox *mbox)
static void __mbox_rx_interrupt(struct omap_mbox *mbox)
{
- struct request *rq;
+ struct omap_mbox_queue *mq = mbox->rxq;
mbox_msg_t msg;
- struct request_queue *q = mbox->rxq->queue;
+ int len;
while (!mbox_fifo_empty(mbox)) {
- rq = blk_get_request(q, WRITE, GFP_ATOMIC);
- if (unlikely(!rq))
+ if (unlikely(kfifo_avail(&mq->fifo) < sizeof(msg))) {
+ omap_mbox_disable_irq(mbox, IRQ_RX);
+ rq_full = true;
goto nomem;
+ }
msg = mbox_fifo_read(mbox);
+ len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
+ WARN_ON(len != sizeof(msg));
- blk_insert_request(q, rq, 0, (void *)msg);
if (mbox->ops->type == OMAP_MBOX_TYPE1)
break;
}
@@ -207,11 +203,9 @@ static irqreturn_t mbox_interrupt(int irq, void *p)
}
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);
@@ -220,11 +214,8 @@ static struct omap_mbox_queue *mbox_queue_alloc(struct omap_mbox *mbox,
spin_lock_init(&mq->lock);
- q = blk_init_queue(proc, &mq->lock);
- if (!q)
+ if (kfifo_alloc(&mq->fifo, mbox_kfifo_size, GFP_KERNEL))
goto error;
- q->queuedata = mbox;
- mq->queue = q;
if (work)
INIT_WORK(&mq->work, work);
@@ -239,7 +230,7 @@ error:
static void mbox_queue_free(struct omap_mbox_queue *q)
{
- blk_cleanup_queue(q->queue);
+ kfifo_free(&q->fifo);
kfree(q);
}
@@ -248,35 +239,35 @@ 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->ops->startup) {
+ mutex_lock(&mbox_configured_lock);
if (!mbox_configured)
ret = mbox->ops->startup(mbox);
- if (unlikely(ret)) {
- write_unlock(&mboxes_lock);
+ if (ret) {
+ mutex_unlock(&mbox_configured_lock);
return ret;
}
mbox_configured++;
- write_unlock(&mboxes_lock);
+ mutex_unlock(&mbox_configured_lock);
}
ret = request_irq(mbox->irq, mbox_interrupt, IRQF_SHARED,
mbox->name, mbox);
- if (unlikely(ret)) {
+ if (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);
+ 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_rxq_fn, mbox_rx_work, NULL);
+ mq = mbox_queue_alloc(mbox, mbox_rx_work, NULL);
if (!mq) {
ret = -ENOMEM;
goto fail_alloc_rxq;
@@ -290,7 +281,7 @@ static int omap_mbox_startup(struct omap_mbox *mbox)
fail_alloc_txq:
free_irq(mbox->irq, mbox);
fail_request_irq:
- if (unlikely(mbox->ops->shutdown))
+ if (mbox->ops->shutdown)
mbox->ops->shutdown(mbox);
return ret;
@@ -298,31 +289,20 @@ static int omap_mbox_startup(struct omap_mbox *mbox)
static void omap_mbox_fini(struct omap_mbox *mbox)
{
+ 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);
- free_irq(mbox->irq, mbox);
-
- if (unlikely(mbox->ops->shutdown)) {
- write_lock(&mboxes_lock);
+ if (mbox->ops->shutdown) {
+ mutex_lock(&mbox_configured_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;
+ mutex_unlock(&mbox_configured_lock);
}
-
- return p;
}
struct omap_mbox *omap_mbox_get(const char *name)
@@ -330,14 +310,15 @@ 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);
- }
+ if (!mboxes)
+ return ERR_PTR(-EINVAL);
- read_unlock(&mboxes_lock);
+ for (mbox = *mboxes; mbox; mbox++)
+ if (!strcmp(mbox->name, name))
+ break;
+
+ if (!mbox)
+ return ERR_PTR(-ENOENT);
ret = omap_mbox_startup(mbox);
if (ret)
@@ -353,70 +334,77 @@ void omap_mbox_put(struct omap_mbox *mbox)
}
EXPORT_SYMBOL(omap_mbox_put);
-int omap_mbox_register(struct device *parent, struct omap_mbox *mbox)
+static struct class omap_mbox_class = { .name = "mbox", };
+
+int omap_mbox_register(struct device *parent, struct omap_mbox **list)
{
- int ret = 0;
- struct omap_mbox **tmp;
+ int ret;
+ int i;
- if (!mbox)
+ mboxes = list;
+ if (!mboxes)
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);
+ 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;
+ }
+ }
return 0;
-err_find:
+err_out:
+ while (i--)
+ device_unregister(mboxes[i]->dev);
return ret;
}
EXPORT_SYMBOL(omap_mbox_register);
-int omap_mbox_unregister(struct omap_mbox *mbox)
+int omap_mbox_unregister(void)
{
- 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);
+ int i;
+
+ if (!mboxes)
+ return -EINVAL;
- 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;
+
mboxd = create_workqueue("mboxd");
if (!mboxd)
return -ENOMEM;
+ /* 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;
}
-module_init(omap_mbox_init);
+subsys_initcall(omap_mbox_init);
static void __exit omap_mbox_exit(void)
{
destroy_workqueue(mboxd);
+ 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 and Hiroshi DOYU");
+MODULE_AUTHOR("Toshihiro Kobayashi");
+MODULE_AUTHOR("Hiroshi DOYU");