[media] V4L: Add camera exposure bias control

The camera may in some conditions incorrectly determine the exposure,
and a manual automatic exposure correction may be needed. This patch
adds V4L2_CID_AUTO_EXPOSURE_BIAS control which allows to add some
offset in the automatic exposure control loop, to compensate for
frame under- or over-exposure.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/include/linux/videodev2.h b/include/linux/videodev2.h
index 07bce86..dfd2098 100644
--- a/include/linux/videodev2.h
+++ b/include/linux/videodev2.h
@@ -1707,6 +1707,8 @@
 #define V4L2_CID_IRIS_ABSOLUTE			(V4L2_CID_CAMERA_CLASS_BASE+17)
 #define V4L2_CID_IRIS_RELATIVE			(V4L2_CID_CAMERA_CLASS_BASE+18)
 
+#define V4L2_CID_AUTO_EXPOSURE_BIAS		(V4L2_CID_CAMERA_CLASS_BASE+19)
+
 /* FM Modulator class control IDs */
 #define V4L2_CID_FM_TX_CLASS_BASE		(V4L2_CTRL_CLASS_FM_TX | 0x900)
 #define V4L2_CID_FM_TX_CLASS			(V4L2_CTRL_CLASS_FM_TX | 1)