Mailbox: Check valid registered callback before calling

This patch checks if the mailbox user has assinged a valid
callback fuction before calling it.

Signed-off-by: Fernando Guzman Lugo <x0095840@ti.com>
Signed-off-by: Hiroshi DOYU <Hiroshi.DOYU@nokia.com>

diff --git a/arch/arm/plat-omap/mailbox.c b/arch/arm/plat-omap/mailbox.c
index 77c23f5a003750fdecf28f17d4ddab06a2ed3258..72efbe5be5781233c2a98ba636f0f1fb26199fc0 100644 (file)
--- a/arch/arm/plat-omap/mailbox.c
+++ b/arch/arm/plat-omap/mailbox.c
@@ -146,7 +146,8 @@ static void mbox_rx_work(struct work_struct *work)
 
                msg = (mbox_msg_t)rq->special;
                blk_end_request_all(rq, 0);
-               mbox->rxq->callback((void *)msg);
+               if (mbox->rxq->callback)
+                       mbox->rxq->callback((void *)msg);
        }
 }