Re: [PATCH 4/7] ARM: shmobile: pfc-sh73a0: Register device tree

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Simon,

On Monday 26 November 2012 09:16:51 Simon Horman wrote:
> Register the pfc with sh73a0_init_gpio_dt() to allow
> gpios provided by pfc to be accessed by devices which
> are registered using device tree.
> 
> The motivation of this is to allow the gpio used for carrier detect
> but the Micro SD SDHI port of the KZM-9A-GT board to be accessed
> using device tree. Thus, allowing the SDHI device of the KZM-9A-GT
> board to be registered using device tree.
> 
> Signed-off-by: Simon Horman <horms@verge.net.au>
> ---
>  arch/arm/mach-shmobile/pfc-sh73a0.c |   45 ++++++++++++++++++++++++++++++++
>  1 file changed, 45 insertions(+)
> 
> diff --git a/arch/arm/mach-shmobile/pfc-sh73a0.c
> b/arch/arm/mach-shmobile/pfc-sh73a0.c index b442f9d..d1a04c0b 100644
> --- a/arch/arm/mach-shmobile/pfc-sh73a0.c
> +++ b/arch/arm/mach-shmobile/pfc-sh73a0.c
> @@ -2797,7 +2797,52 @@ static struct pinmux_info sh73a0_pinmux_info = {
>  	.gpio_irq_size = ARRAY_SIZE(pinmux_irqs),
>  };
> 
> +#ifdef CONFIG_OF_GPIO
> +static int sh73a0_gpio_xlate(struct gpio_chip *gc,
> +			     const struct of_phandle_args *gpiospec,
> +			     u32 *flags)
> +{
> +	if (WARN_ON(gc->of_gpio_n_cells < 2))
> +		return -EINVAL;
> +
> +	if (WARN_ON(gpiospec->args_count < gc->of_gpio_n_cells))
> +		return -EINVAL;
> +
> +	if (gpiospec->args[0] > gc->ngpio)
> +		return -EINVAL;
> +
> +	if (flags)
> +		*flags = gpiospec->args[1];
> +
> +	return gpiospec->args[0];
> +}

Is there any reason not to use of_gpio_simple_xlate here ? If there isn't, 
of_xlate and of_gpio_n_cells default to of_gpio_simple_xlate and 2 
respectively when of_xlate isn't specified, so you could omit both.

> +static const struct of_device_id sh73a0_gpio_dt_match[] __initdata = {
> +	{ .compatible = "renesas,sh_pfc-sh73a0", },
> +	{}
> +};
> +
> +static inline void sh73a0_init_gpio_dt(void)
> +{
> +	struct device_node *of_node;
> +
> +	if (!of_have_populated_dt())
> +		return;
> +
> +	of_node = of_find_matching_node(NULL, sh73a0_gpio_dt_match);
> +	sh73a0_pinmux_info.of_node = of_node;
> +	sh73a0_pinmux_info.of_gpio_n_cells = 2;
> +	sh73a0_pinmux_info.of_xlate = sh73a0_gpio_xlate;
> +}
> +
> +#else
> +
> +static inline void sh73a0_init_gpio_dt(void) {}
> +
> +#endif
> +
>  void sh73a0_pinmux_init(void)
>  {
> +	sh73a0_init_gpio_dt();
>  	register_pinmux(&sh73a0_pinmux_info);
>  }
-- 
Regards,

Laurent Pinchart