[media] V4L: Add camera 3A lock control

The V4L2_CID_3A_LOCK bitmask control allows applications to pause
or resume the automatic exposure, focus and wite balance adjustments.
It can be used, for example, to lock the 3A adjustments right before
a still image is captured, for pre-focus, etc.
The applications can control each of the algorithms independently,
through a corresponding control bit, if driver allows that.

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 092bf5a..a9b03ae 100644
--- a/include/linux/videodev2.h
+++ b/include/linux/videodev2.h
@@ -1758,6 +1758,11 @@
 	V4L2_SCENE_MODE_TEXT			= 13,
 };
 
+#define V4L2_CID_3A_LOCK			(V4L2_CID_CAMERA_CLASS_BASE+27)
+#define V4L2_LOCK_EXPOSURE			(1 << 0)
+#define V4L2_LOCK_WHITE_BALANCE			(1 << 1)
+#define V4L2_LOCK_FOCUS				(1 << 2)
+
 /* 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)