On Fri, Nov 27, 2020 at 09:35:39AM +0100, Geert Uytterhoeven wrote:
> Hi Uwe,
> 
> On Thu, Nov 26, 2020 at 6:03 PM Uwe Kleine-König
> <u.kleine-koenig@pengutronix.de> wrote:
> > The remove callback is only called for devices that were probed
> > successfully before. As the matching probe function cannot complete
> > without error if dev->match_id != PS3_MATCH_ID_SOUND, we don't have to
> > check this here.
> >
> > Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
> 
> Thanks for your patch!
> 
> Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
> 
> Note that there are similar checks in snd_ps3_driver_probe(), which
> can be removed, too:
> 
>         if (WARN_ON(!firmware_has_feature(FW_FEATURE_PS3_LV1)))
>                 return -ENODEV;
>         if (WARN_ON(dev->match_id != PS3_MATCH_ID_SOUND))
>                 return -ENODEV;

I had to invest some brain cycles here. For the first:

Assuming firmware_has_feature(FW_FEATURE_PS3_LV1) always returns the
same value, snd_ps3_driver_probe is only used after this check succeeds
because the driver is registered only after this check in
snd_ps3_init().

The second is superflous because ps3_system_bus_match() yields false if
this doesn't match the driver's match_id.

Best regards
Uwe

-- 
Pengutronix e.K.                           | Uwe Kleine-König            |
Industrial Linux Solutions                 | https://www.pengutronix.de/ |