[PATCH AUTOSEL 5.1 34/95] soundwire: stream: fix bad unlock balance

From: Sasha Levin
Date: Wed Jun 26 2019 - 20:32:23 EST

From: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>

[ Upstream commit 9315d904c7e8f38886e2820fa6cb8d0fa723ea21 ]

the msg lock is taken for multi-link cases only but released
unconditionally, leading to an unlock balance warning for single-link usages
This patch fixes this.

WARNING: bad unlock balance detected!
5.1.0-16506-gc1c383a6f0a2-dirty #1523 Tainted: G W
aplay/2954 is trying to release lock (&bus->msg_lock) at:
but there are no more locks to release!

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
Acked-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
Acked-by: Sanyog Kale <sanyog.r.kale@xxxxxxxxx>
[vkoul: edited the change log as suggested by Pierre]
Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
drivers/soundwire/stream.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/soundwire/stream.c b/drivers/soundwire/stream.c
index 00618de2ee12..794ced434cf2 100644
--- a/drivers/soundwire/stream.c
+++ b/drivers/soundwire/stream.c
@@ -805,7 +805,8 @@ static int do_bank_switch(struct sdw_stream_runtime *stream)
goto error;

- mutex_unlock(&bus->msg_lock);
+ if (bus->multi_link)
+ mutex_unlock(&bus->msg_lock);

return ret;