Re: [PATCH v4 0/4] media: Add entity types

[Sakari Ailus <sakari.ailus@linux.intel.com>]

Laurent Pinchart wrote:
> Hello,
>
> This patch series adds a type field to the media entity structure. It is a
> resend of v3 rebased on top of the latest media master branch, with acks
> collected and spelling mistakes fixed. I have dropped patches 5 to 7 as they
> don't depend on 1-4 and Hans would like to get them merged through his tree,
> and patch 8 as is adds a function that currently has no user.
>
> Let's start with a few words about what types are and are not. The purpose of
> the entity type is to identify the object type that implements the entity, in
> order to safely cast the entity to that object (using container_of()). Three
> types are currently defined, for media entities that are instantiated as such
> (MEDIA_ENTITY_TYPE_MEDIA_ENTITY), embedded in a struct video_device
> (MEDIA_ENTITY_TYPE_VIDEO_DEVICE) or embedded in a struct v4l2_subdev
> (MEDIA_ENTITY_TYPE_V4L2_SUBDEV). The naming is pretty straightforward and
> self-explicit.
>
> Types do not convey any additional information. They don't tell anything about
> the features of the entity or the object that implements it. In particular
> they don't report capabilities of video_device instances, which is why the
> is_media_entity_v4l2_io() function performs additional checks on the video
> device capabilities field, after verifying with the type that it can safely be
> cast to a video_device instance.
>
> The series start by two cleanup patches (1/8 and 2/8) that fix incorrect or
> unneeded usage of the is_media_entity_v4l2_*() functions in the vsp1 and
> exynos4-is drivers. Patch 3/8 then adds the type field to the media_entity
> structure and updates the is_media_entity_v4l2_*() functions implementations.
> Patch 4/8 renames is_media_entity_v4l2_io() to
> is_media_entity_v4l2_video_device() to clarify its purpose.
>
> Cc: Kyungmin Park <kyungmin.park@samsung.com>
> Cc: Sylwester Nawrocki <s.nawrocki@samsung.com>
> Cc: Prabhakar Lad <prabhakar.csengg@gmail.com>
>
> Laurent Pinchart (4):
>    v4l: vsp1: Check if an entity is a subdev with the right function
>    v4l: exynos4-is: Drop unneeded check when setting up fimc-lite links
>    media: Add type field to struct media_entity
>    media: Rename is_media_entity_v4l2_io to
>      is_media_entity_v4l2_video_device
>
>   drivers/media/platform/exynos4-is/fimc-lite.c   | 12 +---
>   drivers/media/platform/exynos4-is/media-dev.c   |  4 +-
>   drivers/media/platform/omap3isp/ispvideo.c      |  2 +-
>   drivers/media/platform/vsp1/vsp1_video.c        |  2 +-
>   drivers/media/v4l2-core/v4l2-dev.c              |  1 +
>   drivers/media/v4l2-core/v4l2-mc.c               |  2 +-
>   drivers/media/v4l2-core/v4l2-subdev.c           |  1 +
>   drivers/staging/media/davinci_vpfe/vpfe_video.c |  2 +-
>   drivers/staging/media/omap4iss/iss_video.c      |  2 +-
>   include/media/media-entity.h                    | 77 +++++++++++++------------
>   10 files changed, 50 insertions(+), 55 deletions(-)
>

For patches 1, 3 and 4:

Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>

-- 
Sakari Ailus
sakari.ailus@linux.intel.com