Hi Hans,

On Sat, 29 Jun 2019, Hans Verkuil wrote:
> sd->entity.graph_obj.mdev can be NULL when this function is called, and
> that breaks existing drivers (rcar-vin, but probably others as well).
>
> Check if sd->entity.num_pads is non-zero instead since that doesn't depend
> on mdev.
>
> Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
> Reported-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> Fixes: a8fa55078a77 ("media: v4l2-subdev: Verify arguments in v4l2_subdev_call()")
> Tested-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>

Thanks, this fixes the following boot regression on r8a7791/koelsch:

     -rcar-vin e6ef0000.video: Device registered as video27
     +rcar-vin e6ef0000.video: Unsupported media bus format for adv7612 13-004c
     +rcar-vin e6ef0000.video: Notifier registration failed
     +rcar-vin: probe of e6ef0000.video failed with error -22

Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>

Gr{oetje,eeting}s,

 						Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
 							    -- Linus Torvalds