[PATCH] Mailbox: Complete wait event only if Tx was successful

Ashwin Chaugule ashwin.chaugule at linaro.org
Wed Dec 10 12:16:12 PST 2014


If a wait_for_completion_timeout() call returns due to a timeout,
the mbox code can still call complete() after returning from the wait.
This can cause subsequent transmissions on a channel to fail, since
the wait_for_completion_timeout() sees the completion variable
is !=0, caused by the erroneous complete() call, and immediately
returns without waiting for the time as expected by the client.

Fix this by calling complete() only if the TX was successful.

Signed-off-by: Ashwin Chaugule <ashwin.chaugule at linaro.org>
---
 drivers/mailbox/mailbox.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mailbox/mailbox.c b/drivers/mailbox/mailbox.c
index 17e9e4a..4acaddb 100644
--- a/drivers/mailbox/mailbox.c
+++ b/drivers/mailbox/mailbox.c
@@ -101,7 +101,7 @@ static void tx_tick(struct mbox_chan *chan, int r)
 	if (mssg && chan->cl->tx_done)
 		chan->cl->tx_done(chan->cl, mssg, r);
 
-	if (chan->cl->tx_block)
+	if ((!r) && chan->cl->tx_block)
 		complete(&chan->tx_complete);
 }
 
-- 
1.9.1




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