Em Mon, 5 Feb 2018 13:42:48 +0100
Hans Verkuil <hverkuil@xxxxxxxxx> escreveu:
> On 02/05/2018 01:39 PM, Mauro Carvalho Chehab wrote:
> > Em Sun, 4 Feb 2018 14:53:31 +0100
> > Hans Verkuil <hverkuil@xxxxxxxxx> escreveu:
> >
> >> Userspace has no way of knowing the pad index for the entity that
> >> owns the pad with the MEDIA_IOC_G_TOPOLOGY ioctl. However, various
> >> v4l-subdev ioctls need to pass this as an argument.
> >
> > While I'm OK on adding a pad index, it still misses a way for Kernelspace
> > to inform the kind of signal it is expected for the cases where an entity
> > provides multiple PAD inputs or outputs with different meanings, e. g.
> > for cases like TV tuner, where different PAD outputs have different
> > signals and should be connected to different entities, based on the PAD
> > type.
> >
> > In other words, we need also either a:
> > - pad name;
> > - pad type;
> > - pad signal.
>
> As mentioned, I agree but it is unrelated to this issue.
>
> >
> >>
> >> Add this missing information.
> >>
> >> Signed-off-by: Hans Verkuil <hans.verkuil@xxxxxxxxx>
> >> ---
> >> RFC, so no documentation yet. This works fine, but how would applications
> >> know that media_v2_pad has been extended with a new index field? Currently
> >> this is 0, which is a valid index.
> >>
> >> If no one is using this API (or only for DVB devices) then we can do that.
> >> The other alternative is to add a new pad flag MEDIA_PAD_FL_HAS_INDEX.
>
> Any comment on this?
Already answered on another e-mail. IMHO, the best here is to increment
the media API version and rely on it.
>
> Regards,
>
> Hans
>
> >> ---
> >> diff --git a/drivers/media/media-device.c b/drivers/media/media-device.c
> >> index e79f72b8b858..16964d3dfb1e 100644
> >> --- a/drivers/media/media-device.c
> >> +++ b/drivers/media/media-device.c
> >> @@ -318,6 +320,7 @@ static long media_device_get_topology(struct media_device *mdev,
> >> kpad.id = pad->graph_obj.id;
> >> kpad.entity_id = pad->entity->graph_obj.id;
> >> kpad.flags = pad->flags;
> >> + kpad.index = pad->index;
> >>
> >> if (copy_to_user(upad, &kpad, sizeof(kpad)))
> >> ret = -EFAULT;
> >> diff --git a/include/uapi/linux/media.h b/include/uapi/linux/media.h
> >> index b9b9446095e9..c3e7a668e122 100644
> >> --- a/include/uapi/linux/media.h
> >> +++ b/include/uapi/linux/media.h
> >> @@ -375,7 +375,8 @@ struct media_v2_pad {
> >> __u32 id;
> >> __u32 entity_id;
> >> __u32 flags;
> >> - __u32 reserved[5];
> >> + __u16 index;
> >> + __u16 reserved[9];
> >> } __attribute__ ((packed));
> >>
> >> struct media_v2_link {
> >
> >
> >
> > Thanks,
> > Mauro
> >
>
Thanks,
Mauro
