The lock in ov9734 is used to protect the streaming state and
serialize the stream on and off callbacks, it should be hold before
checking the streaming state in ov9734_set_stream().
Reported-by: Tomasz Figa <tfiga@xxxxxxxxxxxx>
Reported-by: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx>
Signed-off-by: Bingbu Cao <bingbu.cao@xxxxxxxxx>
---
drivers/media/i2c/ov9734.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/media/i2c/ov9734.c b/drivers/media/i2c/ov9734.c
index 4b9a2e9288e7..e212465489e8 100644
--- a/drivers/media/i2c/ov9734.c
+++ b/drivers/media/i2c/ov9734.c
@@ -637,10 +637,12 @@ static int ov9734_set_stream(struct v4l2_subdev *sd, int enable)
struct i2c_client *client = v4l2_get_subdevdata(sd);
int ret = 0;
- if (ov9734->streaming == enable)
+ mutex_lock(&ov9734->mutex);
+ if (ov9734->streaming == enable) {
+ mutex_unlock(&ov9734->mutex);
return 0;
+ }
- mutex_lock(&ov9734->mutex);
if (enable) {
ret = pm_runtime_get_sync(&client->dev);
if (ret < 0) {
--
2.7.4
