[media] media: Add obj_type field to struct media_entity

Code that processes media entities can require knowledge of the
structure type that embeds a particular media entity instance in order
to cast the entity to the proper object type. This needs is shown by the
presence of the is_media_entity_v4l2_io and is_media_entity_v4l2_subdev
functions.

The implementation of those two functions relies on the entity function
field, which is both a wrong and an inefficient design, without even
mentioning the maintenance issue involved in updating the functions
every time a new entity function is added. Fix this by adding add an
obj_type field to the media entity structure to carry the information.

Signed-off-by: Laurent Pinchart <[email protected]>
Acked-by: Hans Verkuil <[email protected]>
Acked-by: Sakari Ailus <[email protected]>
Signed-off-by: Mauro Carvalho Chehab <[email protected]>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c
index d63083803144..0fa60801a428 100644
--- a/drivers/media/v4l2-core/v4l2-subdev.c
+++ b/drivers/media/v4l2-core/v4l2-subdev.c
@@ -584,6 +584,7 @@ void v4l2_subdev_init(struct v4l2_subdev *sd, const struct v4l2_subdev_ops *ops)
 	sd->host_priv = NULL;
 #if defined(CONFIG_MEDIA_CONTROLLER)
 	sd->entity.name = sd->name;
+	sd->entity.obj_type = MEDIA_ENTITY_TYPE_V4L2_SUBDEV;
 	sd->entity.function = MEDIA_ENT_F_V4L2_SUBDEV_UNKNOWN;
 #endif
 }