Re: [PATCH v2] gpio: dwapb: Make the irqchip immutable

[Andy Shevchenko <andy.shevchenko@xxxxxxxxx>]

On Sat, May 21, 2022 at 1:24 PM Geert Uytterhoeven
<geert+renesas@xxxxxxxxx> wrote:
>
> Commit 6c846d026d49 ("gpio: Don't fiddle with irqchips marked as
> immutable") added a warning to indicate if the gpiolib is altering the
> internals of irqchips.  Following this change the following warning is
> now observed for the dwapb driver:
>
>     gpio gpiochip0: (50200000.gpio): not an immutable chip, please consider fixing it!
>
> Fix this by making the irqchip in the dwapb driver immutable.

Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>

> Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
> ---
> Against gpio/for-next.
> Boot-tested on SiPEED MAiXBiT (Canaan K210).
>
> v2:
>   - Factor out hwirq using preferred helper.
> ---
>  drivers/gpio/gpio-dwapb.c | 38 ++++++++++++++++++++++++--------------
>  1 file changed, 24 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/gpio/gpio-dwapb.c b/drivers/gpio/gpio-dwapb.c
> index 7130195da48d75dd..04afe728e18748df 100644
> --- a/drivers/gpio/gpio-dwapb.c
> +++ b/drivers/gpio/gpio-dwapb.c
> @@ -95,7 +95,6 @@ struct dwapb_context {
>  #endif
>
>  struct dwapb_gpio_port_irqchip {
> -       struct irq_chip         irqchip;
>         unsigned int            nr_irqs;
>         unsigned int            irq[DWAPB_MAX_GPIOS];
>  };
> @@ -252,24 +251,30 @@ static void dwapb_irq_mask(struct irq_data *d)
>  {
>         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
>         struct dwapb_gpio *gpio = to_dwapb_gpio(gc);
> +       irq_hw_number_t hwirq = irqd_to_hwirq(d);
>         unsigned long flags;
>         u32 val;
>
>         raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
> -       val = dwapb_read(gpio, GPIO_INTMASK) | BIT(irqd_to_hwirq(d));
> +       val = dwapb_read(gpio, GPIO_INTMASK) | BIT(hwirq);
>         dwapb_write(gpio, GPIO_INTMASK, val);
>         raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
> +
> +       gpiochip_disable_irq(gc, hwirq);
>  }
>
>  static void dwapb_irq_unmask(struct irq_data *d)
>  {
>         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
>         struct dwapb_gpio *gpio = to_dwapb_gpio(gc);
> +       irq_hw_number_t hwirq = irqd_to_hwirq(d);
>         unsigned long flags;
>         u32 val;
>
> +       gpiochip_enable_irq(gc, hwirq);
> +
>         raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
> -       val = dwapb_read(gpio, GPIO_INTMASK) & ~BIT(irqd_to_hwirq(d));
> +       val = dwapb_read(gpio, GPIO_INTMASK) & ~BIT(hwirq);
>         dwapb_write(gpio, GPIO_INTMASK, val);
>         raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
>  }
> @@ -364,8 +369,23 @@ static int dwapb_irq_set_wake(struct irq_data *d, unsigned int enable)
>
>         return 0;
>  }
> +#else
> +#define dwapb_irq_set_wake     NULL
>  #endif
>
> +static const struct irq_chip dwapb_irq_chip = {
> +       .name           = DWAPB_DRIVER_NAME,
> +       .irq_ack        = dwapb_irq_ack,
> +       .irq_mask       = dwapb_irq_mask,
> +       .irq_unmask     = dwapb_irq_unmask,
> +       .irq_set_type   = dwapb_irq_set_type,
> +       .irq_enable     = dwapb_irq_enable,
> +       .irq_disable    = dwapb_irq_disable,
> +       .irq_set_wake   = dwapb_irq_set_wake,
> +       .flags          = IRQCHIP_IMMUTABLE,
> +       GPIOCHIP_IRQ_RESOURCE_HELPERS,
> +};
> +
>  static int dwapb_gpio_set_debounce(struct gpio_chip *gc,
>                                    unsigned offset, unsigned debounce)
>  {
> @@ -439,16 +459,6 @@ static void dwapb_configure_irqs(struct dwapb_gpio *gpio,
>         girq->default_type = IRQ_TYPE_NONE;
>
>         port->pirq = pirq;
> -       pirq->irqchip.name = DWAPB_DRIVER_NAME;
> -       pirq->irqchip.irq_ack = dwapb_irq_ack;
> -       pirq->irqchip.irq_mask = dwapb_irq_mask;
> -       pirq->irqchip.irq_unmask = dwapb_irq_unmask;
> -       pirq->irqchip.irq_set_type = dwapb_irq_set_type;
> -       pirq->irqchip.irq_enable = dwapb_irq_enable;
> -       pirq->irqchip.irq_disable = dwapb_irq_disable;
> -#ifdef CONFIG_PM_SLEEP
> -       pirq->irqchip.irq_set_wake = dwapb_irq_set_wake;
> -#endif
>
>         /*
>          * Intel ACPI-based platforms mostly have the DesignWare APB GPIO
> @@ -475,7 +485,7 @@ static void dwapb_configure_irqs(struct dwapb_gpio *gpio,
>                 girq->parent_handler = dwapb_irq_handler;
>         }
>
> -       girq->chip = &pirq->irqchip;
> +       gpio_irq_chip_set_chip(girq, &dwapb_irq_chip);
>
>         return;
>
> --
> 2.25.1
>


-- 
With Best Regards,
Andy Shevchenko