Re: [PATCH] media: v4l2-subdev: Fix stream handling for crop API

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

On Tue, Apr 02, 2024 at 12:11:30PM +0300, Tomi Valkeinen wrote:
> On 02/04/2024 11:46, Sakari Ailus wrote:
> > On Tue, Apr 02, 2024 at 11:44:07AM +0300, Laurent Pinchart wrote:
> >> On Tue, Apr 02, 2024 at 08:20:22AM +0000, Sakari Ailus wrote:
> >>> Moi,
> >>>
> >>> On Tue, Apr 02, 2024 at 02:37:25AM +0300, Laurent Pinchart wrote:
> >>>> When support for streams was added to the V4L2 subdev API, the
> >>>> v4l2_subdev_crop structure was extended with a stream field, but the
> >>>> field was not handled in the core code that translates the
> >>>> VIDIOC_SUBDEV_[GS]_CROP ioctls to the selection API. Fix it.
> >>>
> >>> The field is indeed in the UAPI headers. But do we want to support the CROP
> >>> IOCTL for streams? Shouldn't the callers be using the [GS]_SELECTION
> >>> instead?
> >>
> >> They should, but if the field is there, we should support it :-) The
> >> alternative is to remove it. It will cause failures in v4l2-compliance
> >> that we'll need to handle though.
> > 
> > I'd prefer to stick to selections here, this is new functionality so
> > [GS]_CROP support isn't required. I don't have a strong opinion on the
> > matter though.
> 
> Maybe it's easier to just support the stream field, instead of making 
> [GS]_CROP the odd case which looks like it should support streams, but 
> then doesn't...

I'll let the two of you argue and decide, and implement the result :-)

> >>>> Fixes: 2f91e10ee6fd ("media: subdev: add stream based configuration")
> >>>> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> >>>> ---
> >>>>   drivers/media/v4l2-core/v4l2-subdev.c | 2 ++
> >>>>   1 file changed, 2 insertions(+)
> >>>>
> >>>> diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c
> >>>> index 4c6198c48dd6..45836f0a2b0a 100644
> >>>> --- a/drivers/media/v4l2-core/v4l2-subdev.c
> >>>> +++ b/drivers/media/v4l2-core/v4l2-subdev.c
> >>>> @@ -732,6 +732,7 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg,
> >>>>   		memset(&sel, 0, sizeof(sel));
> >>>>   		sel.which = crop->which;
> >>>>   		sel.pad = crop->pad;
> >>>> +		sel.stream = crop->stream;
> >>>>   		sel.target = V4L2_SEL_TGT_CROP;
> >>>>   
> >>>>   		rval = v4l2_subdev_call(
> >>>> @@ -756,6 +757,7 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg,
> >>>>   		memset(&sel, 0, sizeof(sel));
> >>>>   		sel.which = crop->which;
> >>>>   		sel.pad = crop->pad;
> >>>> +		sel.stream = crop->stream;
> >>>>   		sel.target = V4L2_SEL_TGT_CROP;
> >>>>   		sel.r = crop->rect;
> >>>>   
> >>>>
> >>>> base-commit: 39cd87c4eb2b893354f3b850f916353f2658ae6f

-- 
Regards,

Laurent Pinchart