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Diffstat (limited to 'Documentation/userspace-api/media/drivers')
3 files changed, 92 insertions, 0 deletions
diff --git a/Documentation/userspace-api/media/drivers/aspeed-video.rst b/Documentation/userspace-api/media/drivers/aspeed-video.rst new file mode 100644 index 000000000000..1b0cb1e3eba8 --- /dev/null +++ b/Documentation/userspace-api/media/drivers/aspeed-video.rst @@ -0,0 +1,65 @@ +.. SPDX-License-Identifier: GPL-2.0 + +.. include:: <isonum.txt> + +ASPEED video driver +=================== + +ASPEED Video Engine found on AST2400/2500/2600 SoC supports high performance +video compressions with a wide range of video quality and compression ratio +options. The adopted compressing algorithm is a modified JPEG algorithm. + +There are 2 types of compressions in this IP. + +* JPEG JFIF standard mode: for single frame and management compression +* ASPEED proprietary mode: for multi-frame and differential compression. + Support 2-pass (high quality) video compression scheme (Patent pending by + ASPEED). Provide visually lossless video compression quality or to reduce + the network average loading under intranet KVM applications. + +VIDIOC_S_FMT can be used to choose which format you want. V4L2_PIX_FMT_JPEG +stands for JPEG JFIF standard mode; V4L2_PIX_FMT_AJPG stands for ASPEED +proprietary mode. + +More details on the ASPEED video hardware operations can be found in +*chapter 6.2.16 KVM Video Driver* of SDK_User_Guide which available on +AspeedTech-BMC/openbmc/releases. + +The ASPEED video driver implements the following driver-specific control: + +``V4L2_CID_ASPEED_HQ_MODE`` +--------------------------- + Enable/Disable ASPEED's High quality mode. This is a private control + that can be used to enable high quality for aspeed proprietary mode. + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 1 4 + + * - ``(0)`` + - ASPEED HQ mode is disabled. + * - ``(1)`` + - ASPEED HQ mode is enabled. + +``V4L2_CID_ASPEED_HQ_JPEG_QUALITY`` +----------------------------------- + Define the quality of ASPEED's High quality mode. This is a private control + that can be used to decide compression quality if High quality mode enabled + . Higher the value, better the quality and bigger the size. + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 1 4 + + * - ``(1)`` + - minimum + * - ``(12)`` + - maximum + * - ``(1)`` + - step + * - ``(1)`` + - default + +**Copyright** |copy| 2022 ASPEED Technology Inc. diff --git a/Documentation/userspace-api/media/drivers/index.rst b/Documentation/userspace-api/media/drivers/index.rst index 32f82aed47d9..915dbf0f4db5 100644 --- a/Documentation/userspace-api/media/drivers/index.rst +++ b/Documentation/userspace-api/media/drivers/index.rst @@ -31,6 +31,7 @@ For more details see the file COPYING in the source distribution of Linux. :maxdepth: 5 :numbered: + aspeed-video ccs cx2341x-uapi dw100 @@ -38,4 +39,5 @@ For more details see the file COPYING in the source distribution of Linux. max2175 meye-uapi omap3isp-uapi + st-vgxy61 uvcvideo diff --git a/Documentation/userspace-api/media/drivers/st-vgxy61.rst b/Documentation/userspace-api/media/drivers/st-vgxy61.rst new file mode 100644 index 000000000000..d9e3b80e3a96 --- /dev/null +++ b/Documentation/userspace-api/media/drivers/st-vgxy61.rst @@ -0,0 +1,25 @@ +.. SPDX-License-Identifier: GPL-2.0 + +ST VGXY61 camera sensor driver +============================== + +The ST VGXY61 driver implements the following controls: + +``V4L2_CID_HDR_SENSOR_MODE`` +------------------------------- + Change the sensor HDR mode. A HDR picture is obtained by merging two + captures of the same scene using two different exposure periods. + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 1 4 + + * - HDR linearize + - The merger outputs a long exposure capture as long as it is not + saturated. + * - HDR substraction + - This involves subtracting the short exposure frame from the long + exposure frame. + * - No HDR + - This mode is used for standard dynamic range (SDR) exposures. |