linux-kernel - Re: [PATCH 2/8] videodev2.h: add V4L2_DEC_CMD

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20190826203058.0b3ffece@collabora.com>
Date:   Mon, 26 Aug 2019 20:30:58 +0200
From:   Boris Brezillon <boris.brezillon@...labora.com>
To:     Jernej Skrabec <jernej.skrabec@...l.net>
Cc:     mchehab@...nel.org, hverkuil-cisco@...all.nl,
        paul.kocialkowski@...tlin.com, mripard@...nel.org,
        pawel@...iak.com, m.szyprowski@...sung.com,
        kyungmin.park@...sung.com, tfiga@...omium.org, wens@...e.org,
        acourbot@...omium.org, gregkh@...uxfoundation.org,
        linux-media@...r.kernel.org, linux-kernel@...r.kernel.org,
        devel@...verdev.osuosl.org, linux-arm-kernel@...ts.infradead.org,
        ezequiel@...labora.com, jonas@...boo.se
Subject: Re: [PATCH 2/8] videodev2.h: add V4L2_DEC_CMD_FLUSH

On Thu, 22 Aug 2019 21:44:54 +0200
Jernej Skrabec <jernej.skrabec@...l.net> wrote:

> From: Hans Verkuil <hverkuil-cisco@...all.nl>
> 
> Add this new V4L2_DEC_CMD_FLUSH decoder command and document it.
> 
> Signed-off-by: Hans Verkuil <hverkuil-cisco@...all.nl>
> Signed-off-by: Jernej Skrabec <jernej.skrabec@...l.net>

Reviewed-by: Boris Brezillon <boris.brezillon@...labora.com>

> ---
>  Documentation/media/uapi/v4l/vidioc-decoder-cmd.rst | 11 ++++++++++-
>  Documentation/media/videodev2.h.rst.exceptions      |  1 +
>  include/uapi/linux/videodev2.h                      |  1 +
>  3 files changed, 12 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/media/uapi/v4l/vidioc-decoder-cmd.rst b/Documentation/media/uapi/v4l/vidioc-decoder-cmd.rst
> index 57f0066f4cff..0bffef6058f7 100644
> --- a/Documentation/media/uapi/v4l/vidioc-decoder-cmd.rst
> +++ b/Documentation/media/uapi/v4l/vidioc-decoder-cmd.rst
> @@ -208,7 +208,16 @@ introduced in Linux 3.3. They are, however, mandatory for stateful mem2mem decod
>  	been started yet, the driver will return an ``EPERM`` error code. When
>  	the decoder is already running, this command does nothing. No
>  	flags are defined for this command.
> -
> +    * - ``V4L2_DEC_CMD_FLUSH``
> +      - 4
> +      - Flush any held capture buffers. Only valid for stateless decoders,
> +        and only if ``V4L2_BUF_CAP_SUPPORTS_M2M_HOLD_CAPTURE_BUF`` was set.
> +	This command is typically used when the application reached the
> +	end of the stream and the last output buffer had the
> +	``V4L2_BUF_FLAG_M2M_HOLD_CAPTURE_BUF`` flag set. This would prevent
> +	dequeueing the last capture buffer containing the last decoded frame.
> +	So this command can be used to explicitly flush that last decoded
> +	frame.
>  
>  Return Value
>  ============
> diff --git a/Documentation/media/videodev2.h.rst.exceptions b/Documentation/media/videodev2.h.rst.exceptions
> index adeb6b7a15cb..a79028e4d929 100644
> --- a/Documentation/media/videodev2.h.rst.exceptions
> +++ b/Documentation/media/videodev2.h.rst.exceptions
> @@ -434,6 +434,7 @@ replace define V4L2_DEC_CMD_START decoder-cmds
>  replace define V4L2_DEC_CMD_STOP decoder-cmds
>  replace define V4L2_DEC_CMD_PAUSE decoder-cmds
>  replace define V4L2_DEC_CMD_RESUME decoder-cmds
> +replace define V4L2_DEC_CMD_FLUSH decoder-cmds
>  
>  replace define V4L2_DEC_CMD_START_MUTE_AUDIO decoder-cmds
>  replace define V4L2_DEC_CMD_PAUSE_TO_BLACK decoder-cmds
> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
> index 4fa9f543742d..91a79e16089c 100644
> --- a/include/uapi/linux/videodev2.h
> +++ b/include/uapi/linux/videodev2.h
> @@ -1978,6 +1978,7 @@ struct v4l2_encoder_cmd {
>  #define V4L2_DEC_CMD_STOP        (1)
>  #define V4L2_DEC_CMD_PAUSE       (2)
>  #define V4L2_DEC_CMD_RESUME      (3)
> +#define V4L2_DEC_CMD_FLUSH       (4)
>  
>  /* Flags for V4L2_DEC_CMD_START */
>  #define V4L2_DEC_CMD_START_MUTE_AUDIO	(1 << 0)