Re: [PATCH v2 2/2] gpio/omap: auto request GPIO as input if used as IRQ via DT

[Grant Likely <grant.likely@linaro.org>]

On Sat, 22 Jun 2013 00:50:54 +0200, Javier Martinez Canillas <javier.martinez@collabora.co.uk> wrote:
> When an OMAP GPIO is used as an IRQ line, a call to gpio_request()
> has to be made to initialize the OMAP GPIO bank before a driver
> request the IRQ. Otherwise the call to request_irq() fails.
> 
> Drives should not be aware of this neither care wether an IRQ line
> is a GPIO or not. They should just request the IRQ and this has to
> be handled by the irq_chip driver.
> 
> With the current OMAP GPIO DT binding, if we define:
> 
>                 gpio6: gpio@49058000 {
>                         compatible = "ti,omap3-gpio";
>                         reg = <0x49058000 0x200>;
>                         interrupts = <34>;
>                         ti,hwmods = "gpio6";
>                         gpio-controller;
>                         #gpio-cells = <2>;
>                         interrupt-controller;
>                         #interrupt-cells = <2>;
>                 };
> 
>                 interrupt-parent = <&gpio6>;
>                 interrupts = <16 8>;
> 
> The GPIO is correctly mapped as an IRQ but a call to gpio_request()
> is never made. Since a call to the custom IRQ domain .map function
> handler is made for each GPIO used as an IRQ, the GPIO can be setup
> and configured as input there automatically.
> 
> Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
> ---
> 
> Changes since v1:
>   - Split the irq domain mapping function handler and the GPIO
>     request in two different patches.
> 
>  drivers/gpio/gpio-omap.c |    9 +++++++++
>  1 files changed, 9 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c
> index 31cbe65..5ec6a00 100644
> --- a/drivers/gpio/gpio-omap.c
> +++ b/drivers/gpio/gpio-omap.c
> @@ -1092,6 +1092,8 @@ static int omap_gpio_irq_map(struct irq_domain *d, unsigned int virq,
>  			     irq_hw_number_t hwirq)
>  {
>  	struct gpio_bank *bank = d->host_data;
> +	int gpio;
> +	int ret;
>  
>  	if (!bank)
>  		return -EINVAL;
> @@ -1106,6 +1108,13 @@ static int omap_gpio_irq_map(struct irq_domain *d, unsigned int virq,
>  						 handle_simple_irq);
>  			set_irq_flags(virq, IRQF_VALID);
>  		}
> +
> +		gpio = irq_to_gpio(bank, hwirq);
> +		ret = gpio_request_one(gpio, GPIOF_IN, NULL);
> +		if (ret) {
> +			dev_err(bank->dev, "Could not request GPIO%d\n", gpio);
> +			return ret;
> +		}

Following from my comment on patch 1, this is the only bit that you'd
want to be conditional on the presence of a DT, not the whole block.

g.