Re: [PATCH 2/3] ARM: at91/gpio: add irqdomain to gpio interrupts

Rob Herring
2011-11-25T15:36:38Z

On Thu, Nov 24, 2011 at 3:56 PM, Nicolas Ferre <nicolas.ferre@atmel.com> wrote:
> Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
> Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
> ---
>  arch/arm/mach-at91/gpio.c |   19 +++++++++++++++++++
>  1 files changed, 19 insertions(+), 0 deletions(-)
>
> diff --git a/arch/arm/mach-at91/gpio.c b/arch/arm/mach-at91/gpio.c
> index 74d6783..45a39d0 100644
> --- a/arch/arm/mach-at91/gpio.c
> +++ b/arch/arm/mach-at91/gpio.c
> @@ -20,6 +20,7 @@
>  #include <linux/list.h>
>  #include <linux/module.h>
>  #include <linux/io.h>
> +#include <linux/irqdomain.h>
>
>  #include <mach/hardware.h>
>  #include <mach/at91_pio.h>
> @@ -32,6 +33,7 @@ struct at91_gpio_chip {
>        int                     id;             /* ID of register bank */
>        void __iomem            *regbase;       /* Base of register bank */
>        struct clk              *clock;         /* associated clock */
> +       struct irq_domain       domain;         /* associated irq domain */
>  };
>
>  #define to_at91_gpio_chip(c) container_of(c, struct at91_gpio_chip, chip)
> @@ -483,6 +485,20 @@ postcore_initcall(at91_gpio_debugfs_init);
>  /*--------------------------------------------------------------------------*/
>
>  /*
> + * irqdomain initialization: pile up irqdomains on top of AIC range
> + */
> +static void __init at91_gpio_irqdomain(struct at91_gpio_chip *at91_gpio)
> +{
> +       struct irq_domain       *gpio_irq_d = &at91_gpio->domain;
> +
> +       gpio_irq_d->irq_base =
> +               gpio_irq_d->hwirq_base = gpio_to_irq(at91_gpio->chip.base);

This is wrong. hwirq_base is the first irq number relative to the
irq_chip and is generally 0.

irq_base should come from the platform if you need it hardcoded.
Otherwise, it should come from irq_alloc_descs.

> +       gpio_irq_d->nr_irq = at91_gpio->chip.ngpio;
> +       gpio_irq_d->ops = &irq_domain_simple_ops;
> +       irq_domain_add(gpio_irq_d);
> +}
> +
> +/*
>  * This lock class tells lockdep that GPIO irqs are in a different
>  * category than their parents, so it won't report false recursion.
>  */
> @@ -517,6 +533,9 @@ void __init at91_gpio_irq_setup(void)
>                        set_irq_flags(irq, IRQF_VALID);
>                }
>
> +               /* setup irq domain for this GPIO controller */
> +               at91_gpio_irqdomain(this);

I would just inline this code.

Can you use the generic irqchip here? I'm working on a patch to add
irqdomain support to that.

Rob