[media] v4l2-core: add code to check for specific ops
This patch adds a v4l2_subdev_has_op() macro and a v4l2_device_has_op macro to
quickly check if a specific subdev or any subdev supports a particular subdev
operation.
This makes it easy for drivers to disable certain ioctls if none of the subdevs
supports the necessary functionality.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
index 8158a08..c42703a 100644
--- a/include/media/v4l2-subdev.h
+++ b/include/media/v4l2-subdev.h
@@ -687,4 +687,7 @@
((!(sd) || !(sd)->v4l2_dev || !(sd)->v4l2_dev->notify) ? -ENODEV : \
(sd)->v4l2_dev->notify((sd), (notification), (arg)))
+#define v4l2_subdev_has_op(sd, o, f) \
+ ((sd)->ops->o && (sd)->ops->o->f)
+
#endif