[PATCH v5 4/7] v4l2: extend the CSC API to subdevice.
Hans Verkuil
hverkuil at xs4all.nl
Tue Jul 21 09:52:21 EDT 2020
On 03/07/2020 19:10, Dafna Hirschfeld wrote:
> This patch extends the CSC API in video devices to be supported
> also on sub-devices. The flag V4L2_MBUS_FRAMEFMT_SET_CSC set by
> the application when calling VIDIOC_SUBDEV_S_FMT ioctl.
> The flags:
>
> V4L2_SUBDEV_MBUS_CODE_CSC_COLORSPACE, V4L2_SUBDEV_MBUS_CODE_CSC_YCBCR_ENC,
> V4L2_SUBDEV_MBUS_CODE_CSC_QUANTIZATION V4L2_SUBDEV_MBUS_CODE_CSC_XFER_FUNC,
Reorder.
>
> are set by the driver in the VIDIOC_SUBDEV_ENUM_MBUS_CODE ioctl.
>
> New 'flags' fields were added to the structs
> v4l2_subdev_mbus_code_enum, v4l2_mbus_framefmt which are borrowed
> from the 'reserved' field
>
> Signed-off-by: Dafna Hirschfeld <dafna.hirschfeld at collabora.com>
> ---
> .../media/v4l/subdev-formats.rst | 78 +++++++++++++++++--
> .../v4l/vidioc-subdev-enum-mbus-code.rst | 44 ++++++++++-
> include/uapi/linux/v4l2-mediabus.h | 9 ++-
> include/uapi/linux/v4l2-subdev.h | 8 +-
> 4 files changed, 129 insertions(+), 10 deletions(-)
>
> diff --git a/Documentation/userspace-api/media/v4l/subdev-formats.rst b/Documentation/userspace-api/media/v4l/subdev-formats.rst
> index 9a4d61b0d76f..7362ee0b1e96 100644
> --- a/Documentation/userspace-api/media/v4l/subdev-formats.rst
> +++ b/Documentation/userspace-api/media/v4l/subdev-formats.rst
> @@ -41,32 +41,96 @@ Media Bus Formats
> :ref:`field-order` for details.
> * - __u32
> - ``colorspace``
> - - Image colorspace, from enum
> - :c:type:`v4l2_colorspace`. See
> - :ref:`colorspaces` for details.
> + - Image colorspace, from enum :c:type:`v4l2_colorspace`.
> + Must be set by the driver for capture streams and by the application
> + for output streams, see :ref:`colorspaces`. If the application sets the
> + flag ``V4L2_MBUS_FRAMEFMT_SET_CSC`` then the application can set
> + this field for a capture stream to request a specific colorspace
> + for the media bus data. If the driver cannot handle requested
> + conversion, it will return another supported colorspace.
> + The driver indicates that colorspace conversion is supported by setting
> + the flag V4L2_SUBDEV_MBUS_CODE_CSC_COLORSPACE in the corresponding struct
> + :c:type:`v4l2_subdev_mbus_code_enum` during enumeration.
> + See :ref:`colorspaces`.
> * - __u16
> - ``ycbcr_enc``
> - Y'CbCr encoding, from enum :c:type:`v4l2_ycbcr_encoding`.
> This information supplements the ``colorspace`` and must be set by
> the driver for capture streams and by the application for output
> - streams, see :ref:`colorspaces`.
> + streams, see :ref:`colorspaces`. If the application sets the
> + flag ``V4L2_MBUS_FRAMEFMT_SET_CSC`` then the application can set
> + this field for a capture stream to request a specific Y'CbCr encoding
> + for the media bus data. If the driver cannot handle requested
> + conversion, it will return another supported encoding.
> + This field is ignored for HSV media bus formats. The driver indicates
> + that ycbcr_enc conversion is supported by setting the flag
> + V4L2_SUBDEV_MBUS_CODE_CSC_YCBCR_ENC in the corresponding struct
> + :c:type:`v4l2_subdev_mbus_code_enum` during enumeration.
> + See :ref:`v4l2-subdev-mbus-code-flags`.
> +
> * - __u16
> - ``quantization``
> - Quantization range, from enum :c:type:`v4l2_quantization`.
> This information supplements the ``colorspace`` and must be set by
> the driver for capture streams and by the application for output
> - streams, see :ref:`colorspaces`.
> + streams, see :ref:`colorspaces`. If the application sets the
> + flag ``V4L2_MBUS_FRAMEFMT_SET_CSC`` then the application can set
> + this field for a capture stream to request a specific quantization
> + encoding for the media bus data. If the driver cannot handle requested
> + conversion, it will return another supported encoding.
> + The driver indicates that quantization conversion is supported by
> + setting the flag V4L2_SUBDEV_MBUS_CODE_CSC_QUANTIZATION in the
> + corresponding struct :c:type:`v4l2_subdev_mbus_code_enum`
> + during enumeration. See :ref:`v4l2-subdev-mbus-code-flags`.
> +
> * - __u16
> - ``xfer_func``
> - Transfer function, from enum :c:type:`v4l2_xfer_func`.
> This information supplements the ``colorspace`` and must be set by
> the driver for capture streams and by the application for output
> - streams, see :ref:`colorspaces`.
> + streams, see :ref:`colorspaces`. If the application sets the
> + flag ``V4L2_MBUS_FRAMEFMT_SET_CSC`` then the application can set
> + this field for a capture stream to request a specific transfer
> + function for the media bus data. If the driver cannot handle the requested
> + conversion, it will return another supported transfer function.
> + The driver indicates that the transfer function conversion is supported by
> + setting the flag V4L2_SUBDEV_MBUS_CODE_CSC_XFER_FUNC in the
> + corresponding struct :c:type:`v4l2_subdev_mbus_code_enum`
> + during enumeration. See :ref:`v4l2-subdev-mbus-code-flags`.
> + * - __u16
> + - ``reserved2``
> + - Reserved for future extensions.
> + * - __u32
> + - ``flags``
> + - flags See: :ref:v4l2-mbus-framefmt-flags
> * - __u16
> - - ``reserved``\ [11]
> + - ``reserved``\ [8]
> - Reserved for future extensions. Applications and drivers must set
> the array to zero.
>
> +.. _v4l2-mbus-framefmt-flags:
> +
> +.. flat-table:: v4l2_mbus_framefmt Flags
> + :header-rows: 0
> + :stub-columns: 0
> + :widths: 3 1 4
> +
> + * .. _`mbus-framefmt-set-csc`:
> +
> + - ``V4L2_MBUS_FRAMEFMT_SET_CSC``
> + - 0x00000001
> + - Set by the application. It is only used for capture and is
> + ignored for output streams. If set, then request the subdevice to do
> + colorspace conversion from the received colorspace to the requested
> + colorspace values. If colorimetry field (``colorspace``, ``ycbcr_enc``,
If -> If the
> + ``quantization`` or ``xfer_func``) is set to 0, then that colorimetry
Reorder.
> + setting will remain unchanged from what was received. So to change the
> + quantization, only the ``quantization`` field shall be set to non-zero values
> + (``V4L2_QUANTIZATION_FULL_RANGE`` or ``V4L2_QUANTIZATION_LIM_RANGE``)
> + and all other colorimetry fields shall be set to 0.
> +
> + To check which conversions are supported by the hardware for the current
> + media bus frame format, see :ref:`v4l2-subdev-mbus-code-flags`.
>
>
> .. _v4l2-mbus-pixelcode:
> diff --git a/Documentation/userspace-api/media/v4l/vidioc-subdev-enum-mbus-code.rst b/Documentation/userspace-api/media/v4l/vidioc-subdev-enum-mbus-code.rst
> index 35b8607203a4..8ed355a285e9 100644
> --- a/Documentation/userspace-api/media/v4l/vidioc-subdev-enum-mbus-code.rst
> +++ b/Documentation/userspace-api/media/v4l/vidioc-subdev-enum-mbus-code.rst
> @@ -79,11 +79,53 @@ information about the try formats.
> - Media bus format codes to be enumerated, from enum
> :ref:`v4l2_subdev_format_whence <v4l2-subdev-format-whence>`.
> * - __u32
> - - ``reserved``\ [8]
> + - ``flags``
> + - See :ref:`v4l2-subdev-mbus-code-flags`
> + * - __u32
> + - ``reserved``\ [7]
> - Reserved for future extensions. Applications and drivers must set
> the array to zero.
>
>
> +
> +.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{7.7cm}|
> +
> +.. _v4l2-subdev-mbus-code-flags:
> +
> +.. flat-table:: Subdev Media Bus Code Enumerate Flags
> + :header-rows: 0
> + :stub-columns: 0
> + :widths: 1 1 2
> +
> + * - V4L2_SUBDEV_MBUS_CODE_CSC_COLORSPACE
> + - 0x00000001
> + - The driver allows the application to try to change the default colorspace
> + encoding. The application can ask to configure the colorspace of the
> + subdevice when calling the :ref:`VIDIOC_SUBDEV_S_FMT <VIDIOC_SUBDEV_G_FMT>`
> + ioctl with :ref:`V4L2_MBUS_FRAMEFMT_SET_CSC <mbus-framefmt-set-csc>` set.
> + See :ref:`v4l2-mbus-format` on how to do this.
> + * - V4L2_SUBDEV_MBUS_CODE_CSC_YCBCR_ENC
> + - 0x00000002
> + - The driver allows the application to try to change the default Y'CbCr
> + encoding. The application can ask to configure the ycbcr_enc of the
> + subdevice when calling the :ref:`VIDIOC_SUBDEV_S_FMT <VIDIOC_SUBDEV_G_FMT>`
> + ioctl with :ref:`V4L2_MBUS_FRAMEFMT_SET_CSC <mbus-framefmt-set-csc>` set.
> + See :ref:`v4l2-mbus-format` on how to do this.
> + * - V4L2_SUBDEV_MBUS_CODE_CSC_QUANTIZATION
> + - 0x00000004
> + - The driver allows the application to try to change the default
> + quantization. The application can ask to configure the quantization of
> + the subdevice when calling the :ref:`VIDIOC_SUBDEV_S_FMT <VIDIOC_SUBDEV_G_FMT>`
> + ioctl with :ref:`V4L2_MBUS_FRAMEFMT_SET_CSC <mbus-framefmt-set-csc>` set.
> + See :ref:`v4l2-mbus-format` on how to do this.
> + * - V4L2_SUBDEV_MBUS_CODE_CSC_XFER_FUNC
> + - 0x00000008
> + - The driver allows the application to try to change the default transform function.
> + The application can ask to configure the transform function of
> + the subdevice when calling the :ref:`VIDIOC_SUBDEV_S_FMT <VIDIOC_SUBDEV_G_FMT>`
> + ioctl with :ref:`V4L2_MBUS_FRAMEFMT_SET_CSC <mbus-framefmt-set-csc>` set.
> + See :ref:`v4l2-mbus-format` on how to do this.
Reorder and renumber the V4L2_SUBDEV_MBUS_CODE_CSC_ values.
> +
> Return Value
> ============
>
> diff --git a/include/uapi/linux/v4l2-mediabus.h b/include/uapi/linux/v4l2-mediabus.h
> index 123a231001a8..3b7d692b4015 100644
> --- a/include/uapi/linux/v4l2-mediabus.h
> +++ b/include/uapi/linux/v4l2-mediabus.h
> @@ -16,6 +16,8 @@
> #include <linux/types.h>
> #include <linux/videodev2.h>
>
> +#define V4L2_MBUS_FRAMEFMT_SET_CSC 0x00000001
> +
> /**
> * struct v4l2_mbus_framefmt - frame format on the media bus
> * @width: image width
> @@ -26,6 +28,9 @@
> * @ycbcr_enc: YCbCr encoding of the data (from enum v4l2_ycbcr_encoding)
> * @quantization: quantization of the data (from enum v4l2_quantization)
> * @xfer_func: transfer function of the data (from enum v4l2_xfer_func)
> + * @reserved2: two reserved bytes that can be later used
> + * @flags: flags (V4L2_MBUS_FRAMEFMT_*)
> + * @reserved: reserved bytes that can be later used
> */
> struct v4l2_mbus_framefmt {
> __u32 width;
> @@ -36,7 +41,9 @@ struct v4l2_mbus_framefmt {
> __u16 ycbcr_enc;
> __u16 quantization;
> __u16 xfer_func;
> - __u16 reserved[11];
> + __u16 reserved2;
> + __u32 flags;
> + __u16 reserved[8];
> };
>
> #ifndef __KERNEL__
> diff --git a/include/uapi/linux/v4l2-subdev.h b/include/uapi/linux/v4l2-subdev.h
> index 5d2a1dab7911..c20aa9a89864 100644
> --- a/include/uapi/linux/v4l2-subdev.h
> +++ b/include/uapi/linux/v4l2-subdev.h
> @@ -65,19 +65,25 @@ struct v4l2_subdev_crop {
> __u32 reserved[8];
> };
>
> +#define V4L2_SUBDEV_MBUS_CODE_CSC_COLORSPACE 0x00000001
> +#define V4L2_SUBDEV_MBUS_CODE_CSC_YCBCR_ENC 0x00000002
> +#define V4L2_SUBDEV_MBUS_CODE_CSC_QUANTIZATION 0x00000004
> +#define V4L2_SUBDEV_MBUS_CODE_CSC_XFER_FUNC 0x00000008
Reorder and renumber.
Regards,
Hans
> /**
> * struct v4l2_subdev_mbus_code_enum - Media bus format enumeration
> * @pad: pad number, as reported by the media API
> * @index: format index during enumeration
> * @code: format code (MEDIA_BUS_FMT_ definitions)
> * @which: format type (from enum v4l2_subdev_format_whence)
> + * @flags: flags set by the driver, (V4L2_SUBDEV_MBUS_CODE_*)
> */
> struct v4l2_subdev_mbus_code_enum {
> __u32 pad;
> __u32 index;
> __u32 code;
> __u32 which;
> - __u32 reserved[8];
> + __u32 flags;
> + __u32 reserved[7];
> };
>
> /**
>
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