This set introduces the manual request completion API by the author Hans Verkuil and implements it within the MediaTek VCodec driver. Why is this needed? The VCodec driver supports a hardware containing two separate cores, the CORE and the LAT, these are working in a serial manner without this series. This series solves two issues, the first being that the current code runs into a problem, that occurs when the last request object is unbound from the request, before the v4l2_ctrl_request_complete function is called, causing an implicit transition to the COMPLETE state. This issues has been found in applications which didn't attach the controls for the very first request (which is supposed to enable the driver to sniff out the correct formats, etc.). The second issue is that the VCodec driver can not utilize the full performance of both cores, when the LAT core has to wait for the CORE core to finishing processing the decode. Thus by enabling the LAT core to process the next bitstream, right after processing the last we can increase the performance of the driver. With the manual request completion API, we can separate the completion of the request objects of a request and from the completion of the request itself, which allows to send a new bitstream after the LAT core has processed the previous and while the CORE core decodes the previous bitstream, so both cores can work in a parallel manner, but while keeping the request alive during both steps. A new state machine for the VCodec driver ensures, that all necessary processing steps are handled in the correct order depending on the current step in the execution. This state machine has been added to each request to ensure that new requests do not alter the state of still ongoing requests. Additionally, this series adds a small patch to avoid trying to handle a scenario, which is not supported by the hardware and thus runs into a timeout. Signed-off-by: Sebastian Fricke <sebastian.fricke@xxxxxxxxxxxxx> --- Hans Verkuil (3): media: mc: add manual request completion media: vicodec: add support for manual completion media: mc: add debugfs node to keep track of requests Nicolas Dufresne (1): media: mtk-vcodec: Don't try to decode 422/444 VP9 Sebastian Fricke (1): media: vcodec: Implement manual request completion drivers/media/mc/mc-device.c | 30 +++++++++++++ drivers/media/mc/mc-devnode.c | 5 +++ drivers/media/mc/mc-request.c | 44 +++++++++++++++++- .../mediatek/vcodec/common/mtk_vcodec_cmn_drv.h | 13 ++++++ .../mediatek/vcodec/decoder/mtk_vcodec_dec.c | 4 +- .../mediatek/vcodec/decoder/mtk_vcodec_dec_drv.c | 52 ++++++++++++++++++++++ .../mediatek/vcodec/decoder/mtk_vcodec_dec_drv.h | 4 ++ .../vcodec/decoder/mtk_vcodec_dec_stateless.c | 52 ++++++++++++---------- drivers/media/test-drivers/vicodec/vicodec-core.c | 21 +++++++-- include/media/media-device.h | 9 ++++ include/media/media-devnode.h | 4 ++ include/media/media-request.h | 38 +++++++++++++++- 12 files changed, 244 insertions(+), 32 deletions(-) --- base-commit: f2151613e040973c868d28c8b00885dfab69eb75 change-id: 20250312-sebastianfricke-vcodec_manual_request_completion_with_state_machine-6362c7f80a14 Best regards, -- Sebastian Fricke <sebastian.fricke@xxxxxxxxxxxxx>