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    "msgid": "<20221111133025.3102-1-david.plowman@raspberrypi.com>",
    "date": "2022-11-11T13:30:23",
    "name": "[libcamera-devel,0/2] Notify pipeline handlers when a camera is released",
    "submitter": {
        "id": 42,
        "url": "https://patchwork.libcamera.org/api/people/42/?format=api",
        "name": "David Plowman",
        "email": "david.plowman@raspberrypi.com"
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            "date": "2022-11-11T13:30:23",
            "name": "Notify pipeline handlers when a camera is released",
            "version": 1,
            "mbox": "https://patchwork.libcamera.org/series/3606/mbox/"
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        "To": "libcamera-devel@lists.libcamera.org",
        "Date": "Fri, 11 Nov 2022 13:30:23 +0000",
        "Message-Id": "<20221111133025.3102-1-david.plowman@raspberrypi.com>",
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        "Content-Transfer-Encoding": "8bit",
        "Subject": "[libcamera-devel] [PATCH 0/2] Notify pipeline handlers when a\n\tcamera is released",
        "X-BeenThere": "libcamera-devel@lists.libcamera.org",
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        "List-Id": "<libcamera-devel.lists.libcamera.org>",
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        "From": "David Plowman via libcamera-devel <libcamera-devel@lists.libcamera.org>",
        "Reply-To": "David Plowman <david.plowman@raspberrypi.com>",
        "Errors-To": "libcamera-devel-bounces@lists.libcamera.org",
        "Sender": "\"libcamera-devel\" <libcamera-devel-bounces@lists.libcamera.org>"
    },
    "content": "Hi\n\nThese patches are actually a follow-up to an email I circulated on 7th\nNovember, entitled \"Problems opening/closing camera in different\nprocesses\".\n\nIt address the problem that when a camera is released, our pipeline\nhandler never gets to find out. So we have no way to know that this\nwould be a good moment to free all the buffers we allocated for it.\n\nRather than continue the discussion, I thought I'd submit some code!\n\nThere are 2 small patches here.\n\nThe first adds a \"releaseDevice\" method to the PipelineHandler, that\nit calls from its \"release\" method (trying to follow the \"xxx calls\nxxxDevice\" pattern that I saw).\n\nThe second merely implements a \"releaseDevice\" method for the Pi,\nwhich frees any allocated buffers.\n\nThanks!\nDavid\n\nDavid Plowman (2):\n  libcamera: Add a PipelineHandler::releaseDevice method\n  libcamera: pipeline: raspberrypi: Free buffers when a camera is\n    released\n\n include/libcamera/internal/pipeline_handler.h    |  4 +++-\n src/libcamera/camera.cpp                         |  2 +-\n .../pipeline/raspberrypi/raspberrypi.cpp         |  8 ++++++++\n src/libcamera/pipeline_handler.cpp               | 16 +++++++++++++++-\n 4 files changed, 27 insertions(+), 3 deletions(-)"
}