Re: [PATCH v5 02/14] gpio: brcmstb: Use modern PM macros

[Andy Shevchenko]

On Mon, Nov 24, 2025 at 03:20:00PM +0100, Jonas Gorski wrote:
> On Mon, Nov 24, 2025 at 2:52 PM Andy Shevchenko
> <andy.shevchenko@xxxxxxxxx> wrote:
> > On Mon, Nov 24, 2025 at 2:40 PM Jonas Gorski <jonas.gorski@xxxxxxxxx> wrote:
> > > On Mon, Nov 24, 2025 at 1:39 AM Jisheng Zhang <jszhang@xxxxxxxxxx> wrote:

...

> > > >  static const struct dev_pm_ops brcmstb_gpio_pm_ops = {
> > > > -       .suspend_noirq  = brcmstb_gpio_suspend,
> > > > -       .resume_noirq = brcmstb_gpio_resume,
> > > > +       .suspend_noirq = pm_sleep_ptr(brcmstb_gpio_suspend),
> > > > +       .resume_noirq = pm_sleep_ptr(brcmstb_gpio_resume),
> > > >  };

...

> > > > -               .pm = &brcmstb_gpio_pm_ops,
> > > > +               .pm = pm_sleep_ptr(&brcmstb_gpio_pm_ops),
> > >
> > > won't this cause a "brcmstb_gpio_pm_ops is unused" compile warning for
> > > !CONFIG_PM_SLEEP?
> > >
> > > You probably need to add a __maybe_unused to brcmstb_gpio_pm_ops
> > > (which incidentally DEFINE_NOIRQ_DEV_PM_OPS() also doesn't set, but
> > > all other *_DEV_PM_OPS() macros do).

Do they? I mean the modern ones and not that are deprecated.

> > Shouldn't it be covered by the same trick as pm_sleep_ptr() does for functions?
> 
> pm_sleep_ptr() becomes NULL for !CONFIG_PM_SLEEP, so there is no
> reference then anymore to brcmstb_gpio_pm_ops. You would need a
> wrapper for brcmstb_gpio_pm_ops itself to conditionally define it to
> avoid the warning, or add __maybe_unused to it to silence it.

PTR_IF() magic is exactly to make sure compiler will have a visibility while
dropping a dead code. Did I miss anything?

> Note how SIMPLE_DEV_PM_OPS() and UNIVERSAL_DEV_PM_OPS() tag the struct
> with it (for that reason I assume).

Both are deprecated. Not a good orienteer.
None of the new approach uses __maybe_unused. (See DEFINE_*() macros in pm.h.)

-- 
With Best Regards,
Andy Shevchenko