[PATCH 3.16.y-ckt 009/216] [media] smiapp: Take mutex during PLL update in sensor initialisation

[Luis Henriques]

3.16.7-ckt4 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Sakari Ailus <sakari.ailus at linux.intel.com>

commit f85698cd296f08218a7750f321e94607da128600 upstream.

The mutex does not serialise anything in this case but avoids a lockdep
warning from the control framework.

Signed-off-by: Sakari Ailus <sakari.ailus at linux.intel.com>
Acked-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab at osg.samsung.com>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/media/i2c/smiapp/smiapp-core.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/media/i2c/smiapp/smiapp-core.c b/drivers/media/i2c/smiapp/smiapp-core.c
index 698219a9e538..4fff7756bb7f 100644
--- a/drivers/media/i2c/smiapp/smiapp-core.c
+++ b/drivers/media/i2c/smiapp/smiapp-core.c
@@ -2625,7 +2625,9 @@ static int smiapp_registered(struct v4l2_subdev *subdev)
 		pll->flags |= SMIAPP_PLL_FLAG_NO_OP_CLOCKS;
 	pll->scale_n = sensor->limits[SMIAPP_LIMIT_SCALER_N_MIN];
 
+	mutex_lock(&sensor->mutex);
 	rval = smiapp_update_mode(sensor);
+	mutex_unlock(&sensor->mutex);
 	if (rval) {
 		dev_err(&client->dev, "update mode failed\n");
 		goto out_nvm_release;
-- 
2.1.4