Re: [PATCH v2 2/6] iio: light: stk3310: Implement vdd supply and power it off during suspend

Andy Shevchenko
2024-04-24T15:21:46Z

On Wed, Apr 24, 2024 at 3:59 PM Ondřej Jirman <megi@xff.cz> wrote:
> On Wed, Apr 24, 2024 at 02:16:06AM GMT, Andy Shevchenko wrote:
> > On Wed, Apr 24, 2024 at 1:41 AM Aren Moynihan <aren@peacevolution.org> wrote:

...

> > > ret = stk3310_init(indio_dev);
> > > if (ret < 0)
> > > - return ret;
> > > + goto err_vdd_disable;
> >
> > This is wrong. You will have the regulator being disabled _before_
> > IRQ. Note, that the original code likely has a bug which sets states
> > before disabling IRQ and removing a handler.
>
> How so? stk3310_init is called before enabling the interrupt.

Exactly, IRQ is registered with devm and hence the error path and
remove stages will got it in a wrong order.

> Original code has a bug that IRQ is enabled before registering the
> IIO device,

Indeed, but this is another bug.

> so if IRQ is triggered before registration, iio_push_event
> from IRQ handler may be called on a not yet registered IIO device.
>
> Never saw it happen, though. :)

Because nobody cares enough to enable DEBUG_SHIRQ.

--
With Best Regards,
Andy Shevchenko