From: Sebastian Fricke <sebastian.fricke@xxxxxxxxxxxxx> Using V4L2_BUF_FLAG_M2M_HOLD_CAPTURE_BUF flag without specifying the subsystem flag VB2_V4L2_FL_SUPPORTS_M2M_HOLD_CAPTURE_BUF, results in silently ignoring it. Warn the user via a debug print when the flag is requested but ignored by the videobuf2 framework. Signed-off-by: Sebastian Fricke <sebastian.fricke@xxxxxxxxxxxxx> Signed-off-by: Nicolas Dufresne <nicolas.dufresne@xxxxxxxxxxxxx> --- drivers/media/common/videobuf2/videobuf2-v4l2.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c index 6edf4508c636..812c8d1962e0 100644 --- a/drivers/media/common/videobuf2/videobuf2-v4l2.c +++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c @@ -329,8 +329,13 @@ static int vb2_fill_vb2_v4l2_buffer(struct vb2_buffer *vb, struct v4l2_buffer *b */ vbuf->flags &= ~V4L2_BUF_FLAG_TIMECODE; vbuf->field = b->field; - if (!(q->subsystem_flags & VB2_V4L2_FL_SUPPORTS_M2M_HOLD_CAPTURE_BUF)) + if (!(q->subsystem_flags & VB2_V4L2_FL_SUPPORTS_M2M_HOLD_CAPTURE_BUF)) { + if (vbuf->flags & V4L2_BUF_FLAG_M2M_HOLD_CAPTURE_BUF) + dprintk(q, 1, + "Request holding buffer (%d), unsupported on output queue\n", + b->index); vbuf->flags &= ~V4L2_BUF_FLAG_M2M_HOLD_CAPTURE_BUF; + } } else { /* Zero any output buffer flags as this is a capture buffer */ vbuf->flags &= ~V4L2_BUFFER_OUT_FLAGS; -- 2.34.1