Commit d3fe5e6b authored by Laurent Pinchart's avatar Laurent Pinchart Committed by Hans Verkuil
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media: Documentation: Drop deprecated bytesused == 0 



The V4L2 API historically allowed buffers to be queued with bytesused
set to 0 on output devices, in which case the driver would use the
buffer length. This behaviour is deprecated, and videobuf2 prints a
warning message in the kernel log. Drop it from the documentation.

Signed-off-by: default avatarLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: default avatarHans Verkuil <hverkuil-cisco@xs4all.nl>
Reviewed-by: default avatarSakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: default avatarHans Verkuil <hverkuil-cisco@xs4all.nl>
parent e38e42c0

Documentation/userspace-api/media/v4l/buffer.rst

+3 −8
Original line number Diff line number Diff line
@@ -187,10 +187,8 @@ struct v4l2_buffer 
	on the negotiated data format and may change with each buffer for

	compressed variable size data like JPEG images. Drivers must set

	this field when ``type`` refers to a capture stream, applications

	when it refers to an output stream. If the application sets this

	to 0 for an output stream, then ``bytesused`` will be set to the

	size of the buffer (see the ``length`` field of this struct) by

	the driver. For multiplanar formats this field is ignored and the

	when it refers to an output stream. For multiplanar formats this field

        is ignored and the

	``planes`` pointer is used instead.

    * - __u32

      - ``flags``
@@ -327,10 +325,7 @@ struct v4l2_plane 
      - ``bytesused``

      - The number of bytes occupied by data in the plane (its payload).

	Drivers must set this field when ``type`` refers to a capture

	stream, applications when it refers to an output stream. If the

	application sets this to 0 for an output stream, then

	``bytesused`` will be set to the size of the plane (see the

	``length`` field of this struct) by the driver.

	stream, applications when it refers to an output stream.



	.. note::