On 10/04/2018 03:37 PM, Maxime Jourdan wrote:
> When a v4l2 driver exposes V4L2_EVENT_SOURCE_CHANGE, some (usually
> OUTPUT) formats may not be able to trigger this event.
>
> Add a enum_fmt format flag to tag those specific formats.
I think I missed (or forgot) some discussion about this since I have no
idea why this flag is needed. What's the use-case?
Regards,
Hans
>
> Signed-off-by: Maxime Jourdan <mjourdan@xxxxxxxxxxxx>
> ---
> Documentation/media/uapi/v4l/vidioc-enum-fmt.rst | 5 +++++
> include/uapi/linux/videodev2.h | 5 +++--
> 2 files changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/Documentation/media/uapi/v4l/vidioc-enum-fmt.rst b/Documentation/media/uapi/v4l/vidioc-enum-fmt.rst
> index 019c513df217..e0040b36ac43 100644
> --- a/Documentation/media/uapi/v4l/vidioc-enum-fmt.rst
> +++ b/Documentation/media/uapi/v4l/vidioc-enum-fmt.rst
> @@ -116,6 +116,11 @@ one until ``EINVAL`` is returned.
> - This format is not native to the device but emulated through
> software (usually libv4l2), where possible try to use a native
> format instead for better performance.
> + * - ``V4L2_FMT_FLAG_NO_SOURCE_CHANGE``
> + - 0x0004
> + - The event ``V4L2_EVENT_SOURCE_CHANGE`` is not supported
> + for this format.
> +
>
>
> Return Value
> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
> index 3a65951ca51e..a28acee1cb52 100644
> --- a/include/uapi/linux/videodev2.h
> +++ b/include/uapi/linux/videodev2.h
> @@ -723,8 +723,9 @@ struct v4l2_fmtdesc {
> __u32 reserved[4];
> };
>
> -#define V4L2_FMT_FLAG_COMPRESSED 0x0001
> -#define V4L2_FMT_FLAG_EMULATED 0x0002
> +#define V4L2_FMT_FLAG_COMPRESSED 0x0001
> +#define V4L2_FMT_FLAG_EMULATED 0x0002
> +#define V4L2_FMT_FLAG_NO_SOURCE_CHANGE 0x0004
>
> /* Frame Size and frame rate enumeration */
> /*
>
