linux-kernel - Re: (EXT) Re: [PATCH 1/3] gpio: tqmx86: really make IRQ optional

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Message-ID: <CAHp75VfVCTj170S_4Lh9JyDYFfUQLjTtnU=O-iXgUVXcycLxwg@mail.gmail.com>
Date:   Wed, 31 Mar 2021 15:39:51 +0300
From:   Andy Shevchenko <andy.shevchenko@...il.com>
To:     Matthias Schiffer <matthias.schiffer@...tq-group.com>
Cc:     Linus Walleij <linus.walleij@...aro.org>,
        Bartosz Golaszewski <bgolaszewski@...libre.com>,
        Lee Jones <lee.jones@...aro.org>,
        "open list:GPIO SUBSYSTEM" <linux-gpio@...r.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: (EXT) Re: [PATCH 1/3] gpio: tqmx86: really make IRQ optional

On Wed, Mar 31, 2021 at 3:37 PM Matthias Schiffer
<matthias.schiffer@...tq-group.com> wrote:
> On Wed, 2021-03-31 at 15:29 +0300, Andy Shevchenko wrote:
> > On Wed, Mar 31, 2021 at 2:37 PM Matthias Schiffer
> > <matthias.schiffer@...tq-group.com> wrote:

...

> > > -       irq = platform_get_irq(pdev, 0);
> > > -       if (irq < 0)
> > > +       irq = platform_get_irq_optional(pdev, 0);
> > > +       if (irq < 0 && irq != -ENXIO)
> > >                 return irq;
> >
> > This is a dead code now. I suggest you to do the opposite, i.e.
> > if (irq < 0)
> >   irq = 0;
>
> I don't understand which part of the code is dead now. I assume the
> `return irq` case is still useful for unexpected errors, or things like
> EPROBE_DEFER? I'm not sure if EPROBE_DEFER is relevant for this driver,
> but just ignoring the error code completely doesn't seem right to me.

platform_get_irq() AFAIK won't ever return such a code.
So, basically your conditional is always false.

I would like to see the code path which makes my comment wrong.


-- 
With Best Regards,
Andy Shevchenko