Re: [patch 2.6.20-rc1 4/6] PXA GPIO wrappers

Nicolas Pitre
2006-12-21T17:25:09Z

On Thu, 21 Dec 2006, pHilipp Zabel wrote:

> David suggested to have both inline and non-inline functions depending
> on whether gpio is constant. How is this patch?

More comments below.

> --- /dev/null 1970-01-01 00:00:00.000000000 +0000
> +++ linux-2.6/include/asm-arm/arch-pxa/gpio.h 2006-12-21
> 07:57:12.000000000 +0100
> @@ -0,0 +1,86 @@
[...]
> +static inline int gpio_direction_input(unsigned gpio)
> +{
> + if (gpio > PXA_LAST_GPIO)
> + return -EINVAL;
> + pxa_gpio_mode(gpio | GPIO_IN);
> +}
> +
> +static inline int gpio_direction_output(unsigned gpio)
> +{
> + if (gpio > PXA_LAST_GPIO)
> + return -EINVAL;
> + pxa_gpio_mode(gpio | GPIO_OUT);
> +}

Please push this test against PXA_LAST_GPIO inside pxa_gpio_mode(). It
has no advantage to be inline if you're about to call a function anyway.
That would make pxa_gpio_mode() more reliable for those not calling it
through the generic API wrt that kind of error as well.

> --- linux-2.6.orig/arch/arm/mach-pxa/generic.c 2006-12-16
> +++ linux-2.6/arch/arm/mach-pxa/generic.c 2006-12-16 16:47:45.000000000
> @@ -129,6 +129,29 @@
> EXPORT_SYMBOL(pxa_gpio_mode);
>
> /*
> + * Return GPIO level, nonzero means high, zero is low
> + */
> +int pxa_gpio_get_value(unsigned gpio)
> +{
> + return GPLR(gpio) & GPIO_bit(gpio);
> +}
> +
> +EXPORT_SYMBOL(pxa_gpio_get_value);
> +
> +/*
> + * Set output GPIO level
> + */
> +void pxa_gpio_set_value(unsigned gpio, int value)
> +{
> + if (value)
> + GPSR(gpio) = GPIO_bit(gpio);
> + else
> + GPCR(gpio) = GPIO_bit(gpio);
> +}
> +
> +EXPORT_SYMBOL(pxa_gpio_set_value);

Instead of duplicating code here, you probably should just reuse
__gpio_set_value() and __gpio_get_value() inside those functions.

Nicolas