Re: [PATCH 2/3] gpio: dwapb: do not create the irq mapping upfront.

From: delicious quinoa
Date: Thu Mar 20 2014 - 16:20:51 EST


On Thu, Mar 20, 2014 at 2:55 PM, Sebastian Andrzej Siewior
<bigeasy@xxxxxxxxxxxxx> wrote:
> After the irq chip got registered the driver creates a mapping for every
> gpio line. This mapping be useless if the gpio in question never is
> beeing used a irq line. The mapping should be created by the core on
> request.
>
> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
> ---
> drivers/gpio/gpio-dwapb.c | 5 +----
> 1 file changed, 1 insertion(+), 4 deletions(-)
>
> diff --git a/drivers/gpio/gpio-dwapb.c b/drivers/gpio/gpio-dwapb.c
> index 4d25a06b..0db0b94 100644
> --- a/drivers/gpio/gpio-dwapb.c
> +++ b/drivers/gpio/gpio-dwapb.c
> @@ -211,7 +211,7 @@ static void dwapb_configure_irqs(struct dwapb_gpio *gpio,
> struct gpio_chip *gc = &port->bgc.gc;
> struct device_node *node = gc->of_node;
> struct irq_chip_generic *irq_gc;
> - unsigned int hwirq, ngpio = gc->ngpio;
> + unsigned int ngpio = gc->ngpio;
> struct irq_chip_type *ct;
> int err, irq;
>
> @@ -263,9 +263,6 @@ static void dwapb_configure_irqs(struct dwapb_gpio *gpio,
> irq_set_chained_handler(irq, dwapb_irq_handler);
> irq_set_handler_data(irq, gpio);
>
> - for (hwirq = 0 ; hwirq < ngpio ; hwirq++)
> - irq_create_mapping(gpio->domain, hwirq);
> -
> port->bgc.gc.to_irq = dwapb_gpio_to_irq;
> }


Hi Sebastian,

I think this functionality has changed at some point or maybe
everybody copied the same bad code over and over. I see a lot of
legacy gpio drivers calling irq_create_mapping in their to_irq()
functions. Linus Walleij asked me to create the mappings at probe
time. Please see https://lkml.org/lkml/2014/2/10/154 and the
subsequent discussion in https://lkml.org/lkml/2014/2/24/232

Alan Tull
aka
delicious quinoa
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/