[media] media/Documentation: New flag EXECUTE_ON_WRITE
Document new flag V4L2_CTRL_FLAG_EXECUTE_ON_WRITE, and the new behavior
of CH_VALUE event on VOLATILE controls.
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
diff --git a/Documentation/video4linux/v4l2-controls.txt b/Documentation/video4linux/v4l2-controls.txt
index 0f84ce8..5517db6 100644
--- a/Documentation/video4linux/v4l2-controls.txt
+++ b/Documentation/video4linux/v4l2-controls.txt
@@ -344,7 +344,9 @@
}
Note that you use the 'new value' union as well in g_volatile_ctrl. In general
-controls that need to implement g_volatile_ctrl are read-only controls.
+controls that need to implement g_volatile_ctrl are read-only controls. If they
+are not, a V4L2_EVENT_CTRL_CH_VALUE will not be generated when the control
+changes.
To mark a control as volatile you have to set V4L2_CTRL_FLAG_VOLATILE: