Re: [PATCH] gpio: mxc: Improve PM configuration

[Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>]

Hi Bartosz,

On Thu, Jul 20, 2023 at 5:23 PM Bartosz Golaszewski <brgl@xxxxxxxx> wrote:
> On Thu, Jul 20, 2023 at 5:17 PM Bartosz Golaszewski <brgl@xxxxxxxx> wrote:
> > On Tue, Jul 11, 2023 at 9:20 AM Geert Uytterhoeven
> > <geert+renesas@xxxxxxxxx> wrote:
> > > If CONFIG_PM=n (e.g. m68k/allmodconfig):
> > >
> > >     drivers/gpio/gpio-mxc.c:612:12: error: ‘mxc_gpio_runtime_resume’ defined but not used [-Werror=unused-function]
> > >       612 | static int mxc_gpio_runtime_resume(struct device *dev)
> > >           |            ^~~~~~~~~~~~~~~~~~~~~~~
> > >     drivers/gpio/gpio-mxc.c:602:12: error: ‘mxc_gpio_runtime_suspend’ defined but not used [-Werror=unused-function]
> > >       602 | static int mxc_gpio_runtime_suspend(struct device *dev)
> > >           |            ^~~~~~~~~~~~~~~~~~~~~~~~
> > >
> > > Fix this by using the non-SET *_PM_OPS to configure the dev_pm_ops
> > > callbacks, and by wrapping the driver.pm initializer insider pm_ptr().
> > >
> > > As NOIRQ_SYSTEM_SLEEP_PM_OPS() uses pm_sleep_ptr() internally, the
> > > __maybe_unused annotations for the noirq callbacks are no longer needed,
> > > and can be removed.
> > >
> > > Fixes: 3283d820dce649ad ("gpio: mxc: add runtime pm support")
> > > Reported-by: noreply@xxxxxxxxxxxxxx
> > > Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
> > > ---
> > >  drivers/gpio/gpio-mxc.c | 10 +++++-----
> > >  1 file changed, 5 insertions(+), 5 deletions(-)
> > >
> > > diff --git a/drivers/gpio/gpio-mxc.c b/drivers/gpio/gpio-mxc.c
> > > index a9fb6bd9aa6f9645..a43df5d5006e62d3 100644
> > > --- a/drivers/gpio/gpio-mxc.c
> > > +++ b/drivers/gpio/gpio-mxc.c
> > > @@ -623,7 +623,7 @@ static int mxc_gpio_runtime_resume(struct device *dev)
> > >         return 0;
> > >  }
> > >
> > > -static int __maybe_unused mxc_gpio_noirq_suspend(struct device *dev)
> > > +static int mxc_gpio_noirq_suspend(struct device *dev)
> > >  {
> > >         struct platform_device *pdev = to_platform_device(dev);
> > >         struct mxc_gpio_port *port = platform_get_drvdata(pdev);
> > > @@ -634,7 +634,7 @@ static int __maybe_unused mxc_gpio_noirq_suspend(struct device *dev)
> > >         return 0;
> > >  }
> > >
> > > -static int __maybe_unused mxc_gpio_noirq_resume(struct device *dev)
> > > +static int mxc_gpio_noirq_resume(struct device *dev)
> > >  {
> > >         struct platform_device *pdev = to_platform_device(dev);
> > >         struct mxc_gpio_port *port = platform_get_drvdata(pdev);
> > > @@ -647,8 +647,8 @@ static int __maybe_unused mxc_gpio_noirq_resume(struct device *dev)
> > >  }
> > >
> > >  static const struct dev_pm_ops mxc_gpio_dev_pm_ops = {
> > > -       SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(mxc_gpio_noirq_suspend, mxc_gpio_noirq_resume)
> > > -       SET_RUNTIME_PM_OPS(mxc_gpio_runtime_suspend, mxc_gpio_runtime_resume, NULL)
> > > +       NOIRQ_SYSTEM_SLEEP_PM_OPS(mxc_gpio_noirq_suspend, mxc_gpio_noirq_resume)
> > > +       RUNTIME_PM_OPS(mxc_gpio_runtime_suspend, mxc_gpio_runtime_resume, NULL)
> > >  };
> > >
> > >  static int mxc_gpio_syscore_suspend(void)
> > > @@ -695,7 +695,7 @@ static struct platform_driver mxc_gpio_driver = {
> > >                 .name   = "gpio-mxc",
> > >                 .of_match_table = mxc_gpio_dt_ids,
> > >                 .suppress_bind_attrs = true,
> > > -               .pm = &mxc_gpio_dev_pm_ops,
> > > +               .pm = pm_ptr(&mxc_gpio_dev_pm_ops),
> > >         },
> > >         .probe          = mxc_gpio_probe,
> > >  };
> > > --
> > > 2.34.1
> > >
> >
> > Applied, thanks!
> >
> > Bart
>
> Nevermind, Arnd has a better fix for that so I'll apply his change.

I disagree. And my patch was first ;-)

Arnd's version lacks the pm_ptr() around the mxc_gpio_driver.driver.pm
initializer, so the compiler cannot throw out the (rather large) unused
mxc_gpio_dev_pm_ops structure.

Thanks!

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds