There apparently is no reason to require 3 queued buffers to call streamon() for the RkISP1 as the driver operates with a scratch buffer where frames can be directed to if there's no available buffer provided by userspace. Reduce the number of required buffers to 1 to allow applications to operate with a single queued buffer. Tested with libcamera, by operating with a single capture a request. The same request (and associated capture buffer) gets recycled once completed. This of course causes a frame rate drop but doesn't hinder operations. Signed-off-by: Jacopo Mondi <jacopo.mondi@xxxxxxxxxxxxxxxx> --- Adam, a few months ago you were exercizing your pinhole app with a single capture request for StillCapture operations and you got the video device to hang because no enough buffers where provided. This small change should be enough to unblock you. Could you maybe give it a spin if you're still working on this ? Thanks j --- drivers/media/platform/rockchip/rkisp1/rkisp1-capture.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/drivers/media/platform/rockchip/rkisp1/rkisp1-capture.c b/drivers/media/platform/rockchip/rkisp1/rkisp1-capture.c index 2bddb4fa8a5c..34adaecdee54 100644 --- a/drivers/media/platform/rockchip/rkisp1/rkisp1-capture.c +++ b/drivers/media/platform/rockchip/rkisp1/rkisp1-capture.c @@ -35,8 +35,6 @@ #define RKISP1_SP_DEV_NAME RKISP1_DRIVER_NAME "_selfpath" #define RKISP1_MP_DEV_NAME RKISP1_DRIVER_NAME "_mainpath" -#define RKISP1_MIN_BUFFERS_NEEDED 3 - enum rkisp1_plane { RKISP1_PLANE_Y = 0, RKISP1_PLANE_CB = 1, @@ -1563,7 +1561,7 @@ static int rkisp1_register_capture(struct rkisp1_capture *cap) q->ops = &rkisp1_vb2_ops; q->mem_ops = &vb2_dma_contig_memops; q->buf_struct_size = sizeof(struct rkisp1_buffer); - q->min_queued_buffers = RKISP1_MIN_BUFFERS_NEEDED; + q->min_queued_buffers = 1; q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC; q->lock = &node->vlock; q->dev = cap->rkisp1->dev; -- 2.46.1