From 3d238885dbfd5359cd0c12fad858e8638f17bfc6 Mon Sep 17 00:00:00 2001
From: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Date: Tue, 30 Jul 2013 03:34:06 -0300
Subject: [PATCH] [media] V4L2: mt9t031: don't Oops if asynchronous probing is
 attempted

The mt9t031 driver hasn't yet been updated to support asynchronous
subdevice probing. If such a probing is attempted, the driver is allowed
to fail, but it shouldn't Oops. This patch fixes such a potential NULL
pointer dereference.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
---
 drivers/media/i2c/soc_camera/mt9t031.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/media/i2c/soc_camera/mt9t031.c b/drivers/media/i2c/soc_camera/mt9t031.c
index 47d18d0bafe7..ee7bb0ffcecb 100644
--- a/drivers/media/i2c/soc_camera/mt9t031.c
+++ b/drivers/media/i2c/soc_camera/mt9t031.c
@@ -594,9 +594,12 @@ static int mt9t031_s_power(struct v4l2_subdev *sd, int on)
 		ret = soc_camera_power_on(&client->dev, ssdd, mt9t031->clk);
 		if (ret < 0)
 			return ret;
-		vdev->dev.type = &mt9t031_dev_type;
+		if (vdev)
+			/* Not needed during probing, when vdev isn't available yet */
+			vdev->dev.type = &mt9t031_dev_type;
 	} else {
-		vdev->dev.type = NULL;
+		if (vdev)
+			vdev->dev.type = NULL;
 		soc_camera_power_off(&client->dev, ssdd, mt9t031->clk);
 	}
 
-- 
2.20.1