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{
    "id": 12454,
    "url": "https://patchwork.libcamera.org/api/1.1/covers/12454/?format=api",
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        "url": "https://patchwork.libcamera.org/api/1.1/projects/1/?format=api",
        "name": "libcamera",
        "link_name": "libcamera",
        "list_id": "libcamera_core",
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    },
    "msgid": "<20210527220359.30127-1-jacopo@jmondi.org>",
    "date": "2021-05-27T22:03:51",
    "name": "[libcamera-devel,v4,0/8] Implement flush() camera operation",
    "submitter": {
        "id": 3,
        "url": "https://patchwork.libcamera.org/api/1.1/people/3/?format=api",
        "name": "Jacopo Mondi",
        "email": "jacopo@jmondi.org"
    },
    "mbox": "https://patchwork.libcamera.org/cover/12454/mbox/",
    "series": [
        {
            "id": 2088,
            "url": "https://patchwork.libcamera.org/api/1.1/series/2088/?format=api",
            "web_url": "https://patchwork.libcamera.org/project/libcamera/list/?series=2088",
            "date": "2021-05-27T22:03:51",
            "name": "Implement flush() camera operation",
            "version": 4,
            "mbox": "https://patchwork.libcamera.org/series/2088/mbox/"
        }
    ],
    "comments": "https://patchwork.libcamera.org/api/covers/12454/comments/",
    "headers": {
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            "from lancelot.ideasonboard.com (lancelot.ideasonboard.com\n\t[92.243.16.209])\n\tby patchwork.libcamera.org (Postfix) with ESMTPS id 3450BC3206\n\tfor <parsemail@patchwork.libcamera.org>;\n\tThu, 27 May 2021 22:03:21 +0000 (UTC)",
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        ],
        "From": "Jacopo Mondi <jacopo@jmondi.org>",
        "To": "libcamera-devel@lists.libcamera.org",
        "Date": "Fri, 28 May 2021 00:03:51 +0200",
        "Message-Id": "<20210527220359.30127-1-jacopo@jmondi.org>",
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        "Subject": "[libcamera-devel] [PATCH v4 0/8] Implement flush() camera operation",
        "X-BeenThere": "libcamera-devel@lists.libcamera.org",
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        "Sender": "\"libcamera-devel\" <libcamera-devel-bounces@lists.libcamera.org>"
    },
    "content": "To get to a successfull implementation of flush() a bit of preparatory work is\nrequired as currently Requests that fails to queue to the pipeline handler are\nnot returned to the application. Add Request::cancel() and call it in the\nPipelineHandler base class when calling queueRequestDevice() fails to allow\napplication to keep track of the queued requests.\n\nOn top of that, prepare the CameraDevice to support flush with a few clean-up\npatches, then implement the operation.\n\nNo regression detected when running CTS in LIMITED mode.\n\nTested with cros_camera_test:\n\n   # cros_camera_test --gtest_filter=\"Camera3FrameTest/Camera3FlushRequestsTest*\"\n   [==========] 12 tests from 1 test suite ran. (1380 ms total)\n   [  PASSED  ] 12 tests.\n\nAll patches reviewed but the last!\n\nThanks\n  j\n\nv3->v4:\n - [1/8] Set stream to nullptr when the error code does not require it\n - [1/8] Drop a useless error message\n - [2/8] Take in style suggestion from Laurent\n - [4/8] Use enum class CameraDevice::State\n - [8/8] Reimplement flush assuming it only races with processCaptureRequest\n\nv2->v3:\n - Request::cancel():\n   - Add tracepoint in request.tp\n   - Emitt Camera::bufferCompleted signal for each cancelled buffer\n   - Do not complete the Request\n\n - PipelineHandler\n   - Do not emit Camera::bufferCompleted as Request::cancel() does so\n   - Do not complete the request immediately but call\n     PipelineHandler::completeRequest()\n\n - Flush\n   - Use CameraMutex_ in place of FlushMutex_ to wait on the flushed_ condition\n     as suggested by Hiro. This guarantees that any access to the camera state\n     is protected by the same mutex and code is simplified.\n   - Assert that stop() does not get called while flushing as suggested by Hiro.\n\nv1->v2:\n - The majority of patches in the series have not been changed if not for\n   collecting tags. However 8/8 which implement the actual flush() has been\n   changed to address Hiro's comment about protecting close() and\n   configureStreams() from being concurrently run with flush().\n\n   - 8/8:\n     - Introduce a new flushed_ condition variable to be used by close() and\n       configureStreams() to be unlocked when flushing has terminated.\n\n- The patches that introduce Request::cancel() has pending discussion with\n  Hiro and Niklas. As they impact the libcamera API I'll wait for Laurent to\n  chime-in.\n\nJacopo Mondi (8):\n  android: Rework request completion notification\n  libcamera: request: Add Request::cancel()\n  libcamera: pipeline_handler: Cancel Request on queueing failure\n  android: camera_device: Replace running_ with CameraState\n  android: Replace scoped_lock<> with libcamera::MutexLocker\n  android: Guard access to the camera state\n  android: Rename CameraDevice::mutex_\n  android: Implement flush() camera operation\n\n .../libcamera/internal/tracepoints/request.tp |   8 +\n include/libcamera/request.h                   |   1 +\n src/android/camera_device.cpp                 | 236 +++++++++++++-----\n src/android/camera_device.h                   |  18 +-\n src/android/camera_ops.cpp                    |   8 +-\n src/libcamera/pipeline_handler.cpp            |   8 +-\n src/libcamera/request.cpp                     |  23 ++\n 7 files changed, 228 insertions(+), 74 deletions(-)\n\n--\n2.31.1"
}