On 2/11/19 11:13 AM, Hans Verkuil wrote:
> Indicate if a control can only be set through a request, as opposed
> to being set directly. This is necessary for stateless codecs where
> it makes no sense to set the state controls directly.
Kwiboo on irc pointed out that this clashes with this line the in Initialization
section of the stateless decoder API:
"Call VIDIOC_S_EXT_CTRLS() to set all the controls (parsed headers, etc.) required
by the OUTPUT format to enumerate the CAPTURE formats."
So for now ignore patches 4-6: I need to think about this some more.
My worry here is what happens when userspace is adding these controls to a
request and at the same time sets them directly. That may cause weird side-effects.
Regards,
Hans
>
> Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
> ---
> .../media/uapi/v4l/vidioc-queryctrl.rst | 4 ++++
> .../media/videodev2.h.rst.exceptions | 1 +
> include/uapi/linux/videodev2.h | 23 ++++++++++---------
> 3 files changed, 17 insertions(+), 11 deletions(-)
>
> diff --git a/Documentation/media/uapi/v4l/vidioc-queryctrl.rst b/Documentation/media/uapi/v4l/vidioc-queryctrl.rst
> index f824162d0ea9..b08c69cedb92 100644
> --- a/Documentation/media/uapi/v4l/vidioc-queryctrl.rst
> +++ b/Documentation/media/uapi/v4l/vidioc-queryctrl.rst
> @@ -539,6 +539,10 @@ See also the examples in :ref:`control`.
> ``V4L2_CTRL_FLAG_GRABBED`` flag when buffers are allocated or
> streaming is in progress since most drivers do not support changing
> the format in that case.
> + * - ``V4L2_CTRL_FLAG_REQUIRES_REQUESTS``
> + - 0x0800
> + - This control cannot be set directly, but only through a request
> + (i.e. by setting ``which`` to ``V4L2_CTRL_WHICH_REQUEST_VAL``).
>
>
> Return Value
> diff --git a/Documentation/media/videodev2.h.rst.exceptions b/Documentation/media/videodev2.h.rst.exceptions
> index 64d348e67df9..0caa72014dba 100644
> --- a/Documentation/media/videodev2.h.rst.exceptions
> +++ b/Documentation/media/videodev2.h.rst.exceptions
> @@ -351,6 +351,7 @@ replace define V4L2_CTRL_FLAG_VOLATILE control-flags
> replace define V4L2_CTRL_FLAG_HAS_PAYLOAD control-flags
> replace define V4L2_CTRL_FLAG_EXECUTE_ON_WRITE control-flags
> replace define V4L2_CTRL_FLAG_MODIFY_LAYOUT control-flags
> +replace define V4L2_CTRL_FLAG_REQUIRES_REQUESTS control-flags
>
> replace define V4L2_CTRL_FLAG_NEXT_CTRL control
> replace define V4L2_CTRL_FLAG_NEXT_COMPOUND control
> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
> index 7f035d44666e..a78bfdc1df97 100644
> --- a/include/uapi/linux/videodev2.h
> +++ b/include/uapi/linux/videodev2.h
> @@ -1736,17 +1736,18 @@ struct v4l2_querymenu {
> } __attribute__ ((packed));
>
> /* Control flags */
> -#define V4L2_CTRL_FLAG_DISABLED 0x0001
> -#define V4L2_CTRL_FLAG_GRABBED 0x0002
> -#define V4L2_CTRL_FLAG_READ_ONLY 0x0004
> -#define V4L2_CTRL_FLAG_UPDATE 0x0008
> -#define V4L2_CTRL_FLAG_INACTIVE 0x0010
> -#define V4L2_CTRL_FLAG_SLIDER 0x0020
> -#define V4L2_CTRL_FLAG_WRITE_ONLY 0x0040
> -#define V4L2_CTRL_FLAG_VOLATILE 0x0080
> -#define V4L2_CTRL_FLAG_HAS_PAYLOAD 0x0100
> -#define V4L2_CTRL_FLAG_EXECUTE_ON_WRITE 0x0200
> -#define V4L2_CTRL_FLAG_MODIFY_LAYOUT 0x0400
> +#define V4L2_CTRL_FLAG_DISABLED 0x0001
> +#define V4L2_CTRL_FLAG_GRABBED 0x0002
> +#define V4L2_CTRL_FLAG_READ_ONLY 0x0004
> +#define V4L2_CTRL_FLAG_UPDATE 0x0008
> +#define V4L2_CTRL_FLAG_INACTIVE 0x0010
> +#define V4L2_CTRL_FLAG_SLIDER 0x0020
> +#define V4L2_CTRL_FLAG_WRITE_ONLY 0x0040
> +#define V4L2_CTRL_FLAG_VOLATILE 0x0080
> +#define V4L2_CTRL_FLAG_HAS_PAYLOAD 0x0100
> +#define V4L2_CTRL_FLAG_EXECUTE_ON_WRITE 0x0200
> +#define V4L2_CTRL_FLAG_MODIFY_LAYOUT 0x0400
> +#define V4L2_CTRL_FLAG_REQUIRES_REQUESTS 0x0800
>
> /* Query flags, to be ORed with the control ID */
> #define V4L2_CTRL_FLAG_NEXT_CTRL 0x80000000
>
