Re: [PATCH v5] auxdisplay: arm-charlcd: Use DEFINE_SIMPLE_DEV_PM_OPS for power management

[Geert Uytterhoeven]

Hi Li,

On Tue, 25 Aug 2026 at 12:37, Li Jun <lijun01@xxxxxxxxxx> wrote:
> Replace the manually defined dev_pm_ops structure with the
> DEFINE_SIMPLE_DEV_PM_OPS macro to simplify the power management
> code, pm_sleep_ptr() to safely drop the references without
> triggering compiler warnings. This macro automatically handles
> CONFIG_PM_SLEEP configuration and generates freeze/thaw/poweroff/restore
> callbacks, reducing boilerplate code.
>
> Signed-off-by: Li Jun <lijun01@xxxxxxxxxx>

Thanks for the update!

> Changes:
> -Replace SIMPLE_DEV_PM_OPS() in v1 v2 with DEFINE_SIMPLE_DEV_PM_OPS() for pm.
> -Corrected grammar errors in v1 v3 comment.
> -Add a description of pm_sleep_ptr().

But it is still not used?

> --- a/drivers/auxdisplay/arm-charlcd.c
> +++ b/drivers/auxdisplay/arm-charlcd.c
> @@ -306,10 +306,7 @@ static int charlcd_resume(struct device *dev)
>         return 0;
>  }
>
> -static const struct dev_pm_ops charlcd_pm_ops = {
> -       .suspend = charlcd_suspend,
> -       .resume = charlcd_resume,
> -};
> +static DEFINE_SIMPLE_DEV_PM_OPS(charlcd_pm_ops, charlcd_suspend, charlcd_resume);
>
>  static const struct of_device_id charlcd_match[] = {
>         { .compatible = "arm,versatile-lcd", },

Missing:

    -    .pm = &charlcd_pm_ops,
    +   .pm = pm_sleep_ptr(&charlcd_pm_ops),

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