Re: [PATCH 1/4] gpio: mvebu: Add limited PWM support

From: Ralph Sennhauser
Date: Thu Mar 23 2017 - 06:35:23 EST


On Thu, 23 Mar 2017 11:11:09 +0100
Linus Walleij <linus.walleij@xxxxxxxxxx> wrote:

> On Mon, Mar 20, 2017 at 2:51 PM, Thierry Reding
> <thierry.reding@xxxxxxxxx> wrote:
> > On Fri, Mar 17, 2017 at 10:17:47AM +0100, Ralph Sennhauser wrote:
> >> On Thu, 16 Mar 2017 17:03:05 +0100
> >> Linus Walleij <linus.walleij@xxxxxxxxxx> wrote:
> > [...]
> >> > > +static void mvebu_pwm_suspend(struct mvebu_gpio_chip *mvchip)
> >> > > +static void mvebu_pwm_resume(struct mvebu_gpio_chip *mvchip)
> >> >
> >> > I think both of these need to be tagged __maybe_unused to not
> >> > give noise in randconfig builds.
> >>
> >> I haven't seen any warnings with CONFIG_PWM disabled. Which
> >> configuration you expect to trigger a warning? mvebu_pwm_probe
> >> should be the same, right?
> >
> > It's got nothing to do with CONFIG_PWM and as far as I can tell your
> > usage of IS_ENABLED() is fine here. However, if you try building the
> > driver with a !PM configuration, both *_suspend() and *_resume() end
> > up being unused and giving you a warning.
>
> Yes I was referring to the !PM case.

Only this time around I did read !PM not as !PWM and so it became clear
what you meant the first time around and why __maybe_unused is required.

Thanks
Ralph