On Mon, Jan 23, 2023 at 12:43:46PM +0200, Laurent Pinchart wrote:
> Hi Hans,
>
> Thank you for the patch.
>
> On Mon, Jan 23, 2023 at 09:45:49AM +0100, Hans Verkuil wrote:
> > Commit a10b21532574 ("media: vb2: add (un)prepare_streaming queue ops") moved
> > up the q->streaming = 1 assignment to before the call to vb2_start_streaming().
> >
> > This does make sense since q->streaming indicates that VIDIOC_STREAMON is called,
> > and the call to start_streaming happens either at that time or later if
> > q->min_buffers_needed > 0. So q->streaming should be 1 before start_streaming
> > is called.
> >
> > However, it turned out that some drivers use vb2_is_streaming() in buf_queue,
> > and if q->min_buffers_needed == 0, then that will now return true instead of
> > false.
> >
> > So for the time being revert to the original behavior.
> >
> > Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
> > Fixes: a10b21532574 ("media: vb2: add (un)prepare_streaming queue ops")
>
> Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
>
> I'll test it shortly to see if it fixes the VSP1 breakage.
Tested-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
> > ---
> > diff --git a/drivers/media/common/videobuf2/videobuf2-core.c b/drivers/media/common/videobuf2/videobuf2-core.c
> > index fc3758a5bc1c..53e495223ea0 100644
> > --- a/drivers/media/common/videobuf2/videobuf2-core.c
> > +++ b/drivers/media/common/videobuf2/videobuf2-core.c
> > @@ -2149,8 +2149,6 @@ int vb2_core_streamon(struct vb2_queue *q, unsigned int type)
> > if (ret)
> > return ret;
> >
> > - q->streaming = 1;
> > -
> > /*
> > * Tell driver to start streaming provided sufficient buffers
> > * are available.
> > @@ -2161,12 +2159,13 @@ int vb2_core_streamon(struct vb2_queue *q, unsigned int type)
> > goto unprepare;
> > }
> >
> > + q->streaming = 1;
> > +
> > dprintk(q, 3, "successful\n");
> > return 0;
> >
> > unprepare:
> > call_void_qop(q, unprepare_streaming, q);
> > - q->streaming = 0;
> > return ret;
> > }
> > EXPORT_SYMBOL_GPL(vb2_core_streamon);
--
Regards,
Laurent Pinchart
