Re: [PATCH 1/2 v1] gpio: sifive: Set affinity callback to parent

[Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>]

Hi Linus,

On Tue, Nov 17, 2020 at 10:37 PM Linus Walleij <linus.walleij@xxxxxxxxxx> wrote:
> This assigns the .irq_set_affinity to the parent callback.
> I assume the sifive GPIO can be used in systems with
> SMP.
>
> I used the pattern making the hirerarchy tolerant for missing
> parent as in Marc's earlier patches.
>
> Cc: Yash Shah <yash.shah@xxxxxxxxxx>
> Cc: Wesley W. Terpstra <wesley@xxxxxxxxxx>
> Suggested-by: Marc Zyngier <maz@xxxxxxxxxx>
> Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>

Thanks for your patch!

> ---
> ChangeLog RFT->v1:
> - Make the affinity setting call return -EINVAL if there
>   is no parent.

Would it make sense to incorporate this check into
irq_chip_set_affinity_parent(), so drivers can just point
.irq_set_affinity to the latter, without having to provide (duplicate)
the same wrapper over and over?

> - Real patch because now we believe in this
> ---
>  drivers/gpio/gpio-sifive.c | 11 +++++++++++
>  1 file changed, 11 insertions(+)
>
> diff --git a/drivers/gpio/gpio-sifive.c b/drivers/gpio/gpio-sifive.c
> index c54dd08f2cbf..485820e4488c 100644
> --- a/drivers/gpio/gpio-sifive.c
> +++ b/drivers/gpio/gpio-sifive.c
> @@ -128,6 +128,16 @@ static void sifive_gpio_irq_eoi(struct irq_data *d)
>         irq_chip_eoi_parent(d);
>  }
>
> +static int sifive_gpio_irq_set_affinity(struct irq_data *data,
> +                                       const struct cpumask *dest,
> +                                       bool force)
> +{
> +       if (data->parent_data)
> +               return irq_chip_set_affinity_parent(data, dest, force);
> +
> +       return -EINVAL;
> +}
> +
>  static struct irq_chip sifive_gpio_irqchip = {
>         .name           = "sifive-gpio",
>         .irq_set_type   = sifive_gpio_irq_set_type,
> @@ -136,6 +146,7 @@ static struct irq_chip sifive_gpio_irqchip = {
>         .irq_enable     = sifive_gpio_irq_enable,
>         .irq_disable    = sifive_gpio_irq_disable,
>         .irq_eoi        = sifive_gpio_irq_eoi,
> +       .irq_set_affinity = sifive_gpio_irq_set_affinity,
>  };

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