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{
    "id": 3117,
    "url": "https://patchwork.libcamera.org/api/covers/3117/?format=api",
    "web_url": "https://patchwork.libcamera.org/cover/3117/",
    "project": {
        "id": 1,
        "url": "https://patchwork.libcamera.org/api/projects/1/?format=api",
        "name": "libcamera",
        "link_name": "libcamera",
        "list_id": "libcamera_core",
        "list_email": "libcamera-devel@lists.libcamera.org",
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    },
    "msgid": "<20200316214310.27665-1-laurent.pinchart@ideasonboard.com>",
    "date": "2020-03-16T21:43:00",
    "name": "[libcamera-devel,v2,00/10] Simple pipeline handler",
    "submitter": {
        "id": 2,
        "url": "https://patchwork.libcamera.org/api/people/2/?format=api",
        "name": "Laurent Pinchart",
        "email": "laurent.pinchart@ideasonboard.com"
    },
    "mbox": "https://patchwork.libcamera.org/cover/3117/mbox/",
    "series": [
        {
            "id": 724,
            "url": "https://patchwork.libcamera.org/api/series/724/?format=api",
            "web_url": "https://patchwork.libcamera.org/project/libcamera/list/?series=724",
            "date": "2020-03-16T21:43:00",
            "name": "Simple pipeline handler",
            "version": 2,
            "mbox": "https://patchwork.libcamera.org/series/724/mbox/"
        }
    ],
    "comments": "https://patchwork.libcamera.org/api/covers/3117/comments/",
    "headers": {
        "Return-Path": "<laurent.pinchart@ideasonboard.com>",
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            "from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[213.167.242.64])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 8225760422\n\tfor <libcamera-devel@lists.libcamera.org>;\n\tMon, 16 Mar 2020 22:43:20 +0100 (CET)",
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        "From": "Laurent Pinchart <laurent.pinchart@ideasonboard.com>",
        "To": "libcamera-devel@lists.libcamera.org",
        "Cc": "Martijn Braam <martijn@brixit.nl>, Mickael GUENE <mickael.guene@st.com>, \n\tBenjamin GAIGNARD <benjamin.gaignard@st.com>,\n\tAndrey Konovalov <andrey.konovalov@linaro.org>",
        "Date": "Mon, 16 Mar 2020 23:43:00 +0200",
        "Message-Id": "<20200316214310.27665-1-laurent.pinchart@ideasonboard.com>",
        "X-Mailer": "git-send-email 2.24.1",
        "MIME-Version": "1.0",
        "Content-Type": "text/plain; charset=UTF-8",
        "Content-Transfer-Encoding": "8bit",
        "Subject": "[libcamera-devel] [PATCH v2 00/10] Simple pipeline handler",
        "X-BeenThere": "libcamera-devel@lists.libcamera.org",
        "X-Mailman-Version": "2.1.29",
        "Precedence": "list",
        "List-Id": "<libcamera-devel.lists.libcamera.org>",
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        "X-List-Received-Date": "Mon, 16 Mar 2020 21:43:20 -0000"
    },
    "content": "Hello,\n\nThis patch series builds on Martijn's work to implement a pipeline\nhandler for simpler pipelines. Additional information about the pipeline\nhandler itself can be found in patch 08/10.\n\nCompared to v1, this version has been rebased on top of the buffer\nmanagement simplification ([1]). It also includes support for simple\nconverters, V4L2 mem2mem device that perform format conversion, to\nextend the number of supported pixel formats.\n\n[1] https://lists.libcamera.org/pipermail/libcamera-devel/2020-March/007224.html\n\nPatches 01/10 to 07/10 haven't been changed compare to v1. They add a\nV4L2 API extension required for pipeline auto-configuration (01/10), as\nwell aw new utility functions and miscellaneous small extensions (02/10\nto 07/10).\n\nPatch 08/10 adds the new simple pipeline handler, patch 09/10 the\nsimpler converter, and patch 10/10 integrates converter support into the\nsimple pipeline handler. The converter API should probably be improved,\nI've implemented it as a proof of concept. Other options also exist,\nsuch as making the simple pipeline handler a base class from which more\nspecialized pipeline handlers could derive from, and implement support\nfor converters in device-specific code.\n\nThe code has been tested on an i.MX7 platform with a greyscale sensor\nand the i.MX PXP as format converter to produce RGB. I've kept sun6i-csi\nfrom Martijn's work in the list of supported drivers, but supporting\nthat platform will require extending the corresponding driver to support\nthe VIDIOC_ENUM_FMT extension. Once done, if all goes well, the platform\nshould work out of the box.\n\nAs before, this is meant to be compatible with the stm32 and qcom-camss\nthat pipeline handlers have previously been submitted for. The\nrespective drivers need be added to the drivers array in\nSimplePipelineHandler::match(), and, as for sun6i-csi, support for the\nVIDIOC_ENUM_FMT extension needs to be implemented in the drivers, which\nshould be fairly easy.\n\nLaurent Pinchart (9):\n  [DNI] include: linux: Extend VIDIOC_ENUM_FMT to support MC-centric\n    devices\n  libcamera: utils: Add string join function\n  libcamera: v4l2_subdevice: Extend [gs]etFormat() to specify format\n    type\n  libcamera: v4l2_videodevice: Support filtering formats by media bus\n    code\n  libcamera: v4l2_videodevice: Expose the device capabilities\n  libcamera: v4l2_videodevice: Downgrade 4CC conversion errors to\n    warnings\n  libcamera: v4l2_videodevice: Map V4L2_PIX_FMT_GREY to DRM FourCC\n  libcamera: pipeline: simple: Add simple format converter\n  libcamera: pipeline: simple: Integrate converter support\n\nMartijn Braam (1):\n  libcamera: pipeline: Add a simple pipeline handler\n\n include/linux/videodev2.h                   |   4 +-\n src/libcamera/include/utils.h               |  44 +\n src/libcamera/include/v4l2_subdevice.h      |  11 +-\n src/libcamera/include/v4l2_videodevice.h    |   6 +-\n src/libcamera/pipeline/meson.build          |   1 +\n src/libcamera/pipeline/simple/converter.cpp | 210 +++++\n src/libcamera/pipeline/simple/converter.h   |  60 ++\n src/libcamera/pipeline/simple/meson.build   |   4 +\n src/libcamera/pipeline/simple/simple.cpp    | 855 ++++++++++++++++++++\n src/libcamera/utils.cpp                     |  16 +\n src/libcamera/v4l2_subdevice.cpp            |  23 +-\n src/libcamera/v4l2_videodevice.cpp          |  36 +-\n test/utils.cpp                              |   7 +-\n 13 files changed, 1261 insertions(+), 16 deletions(-)\n create mode 100644 src/libcamera/pipeline/simple/converter.cpp\n create mode 100644 src/libcamera/pipeline/simple/converter.h\n create mode 100644 src/libcamera/pipeline/simple/meson.build\n create mode 100644 src/libcamera/pipeline/simple/simple.cpp"
}