1 files changed, 76 insertions, 54 deletions

diff --git a/arch/arm/plat-omap/mailbox.c b/arch/arm/plat-omap/mailbox.c
index d2fafb892f7f..459b319a9fad 100644
--- a/arch/arm/plat-omap/mailbox.c
+++ b/arch/arm/plat-omap/mailbox.c
@@ -28,12 +28,12 @@
 #include <linux/slab.h>
 #include <linux/kfifo.h>
 #include <linux/err.h>
+#include <linux/notifier.h>
 
 #include <plat/mailbox.h>
 
 static struct workqueue_struct *mboxd;
 static struct omap_mbox **mboxes;
-static bool rq_full;
 
 static int mbox_configured;
 static DEFINE_MUTEX(mbox_configured_lock);
@@ -93,20 +93,25 @@ 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(&mq->lock);
+        spin_lock_bh(&mq->lock);
 
         if (kfifo_avail(&mq->fifo) < sizeof(msg)) {
                 ret = -ENOMEM;
                 goto out;
         }
 
+        if (kfifo_is_empty(&mq->fifo) && !__mbox_poll_for_space(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(&mq->lock);
+        spin_unlock_bh(&mq->lock);
         return ret;
 }
 EXPORT_SYMBOL(omap_mbox_msg_send);
@@ -146,8 +151,14 @@ static void mbox_rx_work(struct work_struct *work)
                 len = kfifo_out(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
                 WARN_ON(len != sizeof(msg));
 
-                if (mq->callback)
-                        mq->callback((void *)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);
         }
 }
 
@@ -170,7 +181,7 @@ static void __mbox_rx_interrupt(struct omap_mbox *mbox)
         while (!mbox_fifo_empty(mbox)) {
                 if (unlikely(kfifo_avail(&mq->fifo) < sizeof(msg))) {
                         omap_mbox_disable_irq(mbox, IRQ_RX);
-                        rq_full = true;
+                        mq->full = true;
                         goto nomem;
                 }
 
@@ -239,73 +250,77 @@ static int omap_mbox_startup(struct omap_mbox *mbox)
         int ret = 0;
         struct omap_mbox_queue *mq;
 
-        if (mbox->ops->startup) {
-                mutex_lock(&mbox_configured_lock);
-                if (!mbox_configured)
+        mutex_lock(&mbox_configured_lock);
+        if (!mbox_configured++) {
+                if (likely(mbox->ops->startup)) {
                         ret = mbox->ops->startup(mbox);
-
-                if (ret) {
-                        mutex_unlock(&mbox_configured_lock);
-                        return ret;
-                }
-                mbox_configured++;
-                mutex_unlock(&mbox_configured_lock);
-        }
-
-        ret = request_irq(mbox->irq, mbox_interrupt, IRQF_SHARED,
-                                mbox->name, mbox);
-        if (ret) {
-                printk(KERN_ERR
-                        "failed to register mailbox interrupt:%d\n", ret);
-                goto fail_request_irq;
+                        if (unlikely(ret))
+                                goto fail_startup;
+                } else
+                        goto fail_startup;
         }
 
-        mq = mbox_queue_alloc(mbox, NULL, mbox_tx_tasklet);
-        if (!mq) {
-                ret = -ENOMEM;
-                goto fail_alloc_txq;
-        }
-        mbox->txq = mq;
+        if (!mbox->use_count++) {
+                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;
+                }
+                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;
+                mq = mbox_queue_alloc(mbox, mbox_rx_work, NULL);
+                if (!mq) {
+                        ret = -ENOMEM;
+                        goto fail_alloc_rxq;
+                }
+                mbox->rxq = mq;
+                mq->mbox = mbox;
         }
-        mbox->rxq = mq;
-
+        mutex_unlock(&mbox_configured_lock);
         return 0;
 
- fail_alloc_rxq:
+fail_alloc_rxq:
         mbox_queue_free(mbox->txq);
- fail_alloc_txq:
+fail_alloc_txq:
         free_irq(mbox->irq, mbox);
- fail_request_irq:
+fail_request_irq:
         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)
 {
-        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);
+        mutex_lock(&mbox_configured_lock);
+
+        if (!--mbox->use_count) {
+                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 (mbox->ops->shutdown) {
-                mutex_lock(&mbox_configured_lock);
-                if (mbox_configured > 0)
-                        mbox_configured--;
-                if (!mbox_configured)
+        if (likely(mbox->ops->shutdown)) {
+                if (!--mbox_configured)
                         mbox->ops->shutdown(mbox);
-                mutex_unlock(&mbox_configured_lock);
         }
+
+        mutex_unlock(&mbox_configured_lock);
 }
 
-struct omap_mbox *omap_mbox_get(const char *name)
+struct omap_mbox *omap_mbox_get(const char *name, struct notifier_block *nb)
 {
         struct omap_mbox *mbox;
         int ret;
@@ -324,12 +339,16 @@ struct omap_mbox *omap_mbox_get(const char *name)
         if (ret)
                 return ERR_PTR(-ENODEV);
 
+        if (nb)
+                blocking_notifier_chain_register(&mbox->notifier, nb);
+
         return mbox;
 }
 EXPORT_SYMBOL(omap_mbox_get);
 
-void omap_mbox_put(struct omap_mbox *mbox)
+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);
@@ -353,6 +372,8 @@ int omap_mbox_register(struct device *parent, struct omap_mbox **list)
                         ret = PTR_ERR(mbox->dev);
                         goto err_out;
                 }
+
+                BLOCKING_INIT_NOTIFIER_HEAD(&mbox->notifier);
         }
         return 0;
 
@@ -391,7 +412,8 @@ static int __init omap_mbox_init(void)
 
         /* 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));
+        mbox_kfifo_size = max_t(unsigned int, mbox_kfifo_size,
+                                                        sizeof(mbox_msg_t));
 
         return 0;
 }