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diff --git a/Documentation/media/v4l-drivers/fimc.rst b/Documentation/media/v4l-drivers/fimc.rst deleted file mode 100644 index 0b8ddc4a3008..000000000000 --- a/Documentation/media/v4l-drivers/fimc.rst +++ /dev/null @@ -1,153 +0,0 @@ -.. SPDX-License-Identifier: GPL-2.0 - -.. include:: <isonum.txt> - -The Samsung S5P/EXYNOS4 FIMC driver -=================================== - -Copyright |copy| 2012 - 2013 Samsung Electronics Co., Ltd. - -The FIMC (Fully Interactive Mobile Camera) device available in Samsung -SoC Application Processors is an integrated camera host interface, color -space converter, image resizer and rotator. It's also capable of capturing -data from LCD controller (FIMD) through the SoC internal writeback data -path. There are multiple FIMC instances in the SoCs (up to 4), having -slightly different capabilities, like pixel alignment constraints, rotator -availability, LCD writeback support, etc. The driver is located at -drivers/media/platform/exynos4-is directory. - -Supported SoCs --------------- - -S5PC100 (mem-to-mem only), S5PV210, EXYNOS4210 - -Supported features ------------------- - -- camera parallel interface capture (ITU-R.BT601/565); -- camera serial interface capture (MIPI-CSI2); -- memory-to-memory processing (color space conversion, scaling, mirror - and rotation); -- dynamic pipeline re-configuration at runtime (re-attachment of any FIMC - instance to any parallel video input or any MIPI-CSI front-end); -- runtime PM and system wide suspend/resume - -Not currently supported ------------------------ - -- LCD writeback input -- per frame clock gating (mem-to-mem) - -User space interfaces ---------------------- - -Media device interface -~~~~~~~~~~~~~~~~~~~~~~ - -The driver supports Media Controller API as defined at :ref:`media_controller`. -The media device driver name is "SAMSUNG S5P FIMC". - -The purpose of this interface is to allow changing assignment of FIMC instances -to the SoC peripheral camera input at runtime and optionally to control internal -connections of the MIPI-CSIS device(s) to the FIMC entities. - -The media device interface allows to configure the SoC for capturing image -data from the sensor through more than one FIMC instance (e.g. for simultaneous -viewfinder and still capture setup). - -Reconfiguration is done by enabling/disabling media links created by the driver -during initialization. The internal device topology can be easily discovered -through media entity and links enumeration. - -Memory-to-memory video node -~~~~~~~~~~~~~~~~~~~~~~~~~~~ - -V4L2 memory-to-memory interface at /dev/video? device node. This is standalone -video device, it has no media pads. However please note the mem-to-mem and -capture video node operation on same FIMC instance is not allowed. The driver -detects such cases but the applications should prevent them to avoid an -undefined behaviour. - -Capture video node -~~~~~~~~~~~~~~~~~~ - -The driver supports V4L2 Video Capture Interface as defined at -:ref:`devices`. - -At the capture and mem-to-mem video nodes only the multi-planar API is -supported. For more details see: :ref:`planar-apis`. - -Camera capture subdevs -~~~~~~~~~~~~~~~~~~~~~~ - -Each FIMC instance exports a sub-device node (/dev/v4l-subdev?), a sub-device -node is also created per each available and enabled at the platform level -MIPI-CSI receiver device (currently up to two). - -sysfs -~~~~~ - -In order to enable more precise camera pipeline control through the sub-device -API the driver creates a sysfs entry associated with "s5p-fimc-md" platform -device. The entry path is: /sys/platform/devices/s5p-fimc-md/subdev_conf_mode. - -In typical use case there could be a following capture pipeline configuration: -sensor subdev -> mipi-csi subdev -> fimc subdev -> video node - -When we configure these devices through sub-device API at user space, the -configuration flow must be from left to right, and the video node is -configured as last one. - -When we don't use sub-device user space API the whole configuration of all -devices belonging to the pipeline is done at the video node driver. -The sysfs entry allows to instruct the capture node driver not to configure -the sub-devices (format, crop), to avoid resetting the subdevs' configuration -when the last configuration steps at the video node is performed. - -For full sub-device control support (subdevs configured at user space before -starting streaming): - -.. code-block:: none - - # echo "sub-dev" > /sys/platform/devices/s5p-fimc-md/subdev_conf_mode - -For V4L2 video node control only (subdevs configured internally by the host -driver): - -.. code-block:: none - - # echo "vid-dev" > /sys/platform/devices/s5p-fimc-md/subdev_conf_mode - -This is a default option. - -5. Device mapping to video and subdev device nodes --------------------------------------------------- - -There are associated two video device nodes with each device instance in -hardware - video capture and mem-to-mem and additionally a subdev node for -more precise FIMC capture subsystem control. In addition a separate v4l2 -sub-device node is created per each MIPI-CSIS device. - -How to find out which /dev/video? or /dev/v4l-subdev? is assigned to which -device? - -You can either grep through the kernel log to find relevant information, i.e. - -.. code-block:: none - - # dmesg | grep -i fimc - -(note that udev, if present, might still have rearranged the video nodes), - -or retrieve the information from /dev/media? with help of the media-ctl tool: - -.. code-block:: none - - # media-ctl -p - -7. Build --------- - -If the driver is built as a loadable kernel module (CONFIG_VIDEO_SAMSUNG_S5P_FIMC=m) -two modules are created (in addition to the core v4l2 modules): s5p-fimc.ko and -optional s5p-csis.ko (MIPI-CSI receiver subdev). |