Commit 84060c65 authored by Stanimir Varbanov's avatar Stanimir Varbanov Committed by Mauro Carvalho Chehab
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media: media/doc: Allow sizeimage to be set by v4l clients 



This changes v4l2_pix_format and v4l2_plane_pix_format sizeimage
field description to allow v4l clients to set bigger image size
in case of variable length compressed data.

Presently s5p-mfc and mtk-vcodec codec drivers use that. Lets
make it obvious in the documentation.

Signed-off-by: default avatarStanimir Varbanov <stanimir.varbanov@linaro.org>
Signed-off-by: default avatarHans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+samsung@kernel.org>
parent e96a8819

Documentation/media/uapi/v4l/pixfmt-v4l2-mplane.rst

+14 −1
Original line number Diff line number Diff line
@@ -31,7 +31,20 @@ describing all planes of that format. 


    * - __u32

      - ``sizeimage``

      - Maximum size in bytes required for image data in this plane.

      - Maximum size in bytes required for image data in this plane,

	set by the driver. When the image consists of variable length

	compressed data this is the number of bytes required by the

	codec to support the worst-case compression scenario.



	The driver will set the value for uncompressed images.



	Clients are allowed to set the sizeimage field for variable length

	compressed data flagged with ``V4L2_FMT_FLAG_COMPRESSED`` at

	:ref:`VIDIOC_ENUM_FMT`, but the driver may ignore it and set the

	value itself, or it may modify the provided value based on

	alignment requirements or minimum/maximum size requirements.

	If the client wants to leave this to the driver, then it should

	set sizeimage to 0.

    * - __u32

      - ``bytesperline``

      - Distance in bytes between the leftmost pixels in two adjacent

Documentation/media/uapi/v4l/pixfmt-v4l2.rst

+12 −1
Original line number Diff line number Diff line
@@ -89,7 +89,18 @@ Single-planar format structure 
      - Size in bytes of the buffer to hold a complete image, set by the

	driver. Usually this is ``bytesperline`` times ``height``. When

	the image consists of variable length compressed data this is the

	maximum number of bytes required to hold an image.

	number of bytes required by the codec to support the worst-case

	compression scenario.



	The driver will set the value for uncompressed images.



	Clients are allowed to set the sizeimage field for variable length

	compressed data flagged with ``V4L2_FMT_FLAG_COMPRESSED`` at

	:ref:`VIDIOC_ENUM_FMT`, but the driver may ignore it and set the

	value itself, or it may modify the provided value based on

	alignment requirements or minimum/maximum size requirements.

	If the client wants to leave this to the driver, then it should

	set sizeimage to 0.

    * - __u32

      - ``colorspace``

      - Image colorspace, from enum :c:type:`v4l2_colorspace`.