[PATCH] ep93xx: implement gpiolib set_debounce for built-in GPIOs

[Ryan Mallon]

On 01/27/2011 12:22 PM, H Hartley Sweeten wrote:
> GPIO Ports A, B, and F on the ep93xx provide interrupt capability.  It is
> possible to debounce the input signal on these ports when interrupts are
> enabled.
> 
> Support for this debounce capability was provided with an ep93xx internal
> function.  Now that gpiolib knows about gpio debounce, use the gpiolib
> method and do not export the internal function.
> 
> Signed-off-by: H Hartley Sweeten <hsweeten at visionengravers.com>
> Cc: Ryan Mallon <ryan at bluewatersys.com>
> 
> ---
> 
> diff --git a/arch/arm/mach-ep93xx/gpio.c b/arch/arm/mach-ep93xx/gpio.c
> index bec34b8..a889fa7 100644
> --- a/arch/arm/mach-ep93xx/gpio.c
> +++ b/arch/arm/mach-ep93xx/gpio.c
> @@ -61,7 +61,7 @@ static inline void ep93xx_gpio_int_mask(unsigned line)
>  	gpio_int_unmasked[line >> 3] &= ~(1 << (line & 7));
>  }
>  
> -void ep93xx_gpio_int_debounce(unsigned int irq, int enable)
> +static void ep93xx_gpio_int_debounce(unsigned int irq, bool enable)
>  {
>  	int line = irq_to_gpio(irq);
>  	int port = line >> 3;
> @@ -75,7 +75,6 @@ void ep93xx_gpio_int_debounce(unsigned int irq, int enable)
>  	__raw_writeb(gpio_int_debounce[port],
>  		EP93XX_GPIO_REG(int_debounce_register_offset[port]));
>  }
> -EXPORT_SYMBOL(ep93xx_gpio_int_debounce);
>  
>  static void ep93xx_gpio_ab_irq_handler(unsigned int irq, struct irq_desc *desc)
>  {
> @@ -335,6 +334,20 @@ static void ep93xx_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
>  	local_irq_restore(flags);
>  }
>  
> +static int ep93xx_gpio_set_debounce(struct gpio_chip *chip,
> +				    unsigned offset, unsigned debounce)
> +{
> +	int gpio = chip->base + offset;
> +	int irq = gpio_to_irq(gpio);
> +
> +	if (irq < 0)
> +		return -EINVAL;
> +
> +	ep93xx_gpio_int_debounce(irq, debounce ? true : false);

We should just move the code from ep93xx_gpio_int_debounce here. Why
have two functions to do one thing?

> +
> +	return 0;
> +}
> +
>  static void ep93xx_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
>  {
>  	struct ep93xx_gpio_chip *ep93xx_chip = to_ep93xx_gpio_chip(chip);
> @@ -434,6 +447,18 @@ void __init ep93xx_gpio_init(void)
>  				 EP93XX_SYSCON_DEVCFG_GONIDE |
>  				 EP93XX_SYSCON_DEVCFG_HONIDE);
>  
> -	for (i = 0; i < ARRAY_SIZE(ep93xx_gpio_banks); i++)
> -		gpiochip_add(&ep93xx_gpio_banks[i].chip);
> +	for (i = 0; i < ARRAY_SIZE(ep93xx_gpio_banks); i++) {
> +		struct gpio_chip *chip = &ep93xx_gpio_banks[i].chip;
> +
> +		/*
> +		 * Ports A, B, and F support input debouncing when
> +		 * used as interrupts.
> +		 */
> +		if (!strcmp(chip->label, "A") ||
> +		    !strcmp(chip->label, "B") ||
> +		    !strcmp(chip->label, "F"))

This could just be if *chip->label == 'A'. I don't really mind either way.

> +			chip->set_debounce = ep93xx_gpio_set_debounce;
> +
> +		gpiochip_add(chip);
> +	}
>  }
> diff --git a/arch/arm/mach-ep93xx/include/mach/gpio.h b/arch/arm/mach-ep93xx/include/mach/gpio.h
> index c991b14..c57152c 100644
> --- a/arch/arm/mach-ep93xx/include/mach/gpio.h
> +++ b/arch/arm/mach-ep93xx/include/mach/gpio.h
> @@ -99,8 +99,6 @@
>  /* maximum value for irq capable line identifiers */
>  #define EP93XX_GPIO_LINE_MAX_IRQ	EP93XX_GPIO_LINE_F(7)
>  
> -extern void ep93xx_gpio_int_debounce(unsigned int irq, int enable);
> -
>  /* new generic GPIO API - see Documentation/gpio.txt */
>  
>  #include <asm-generic/gpio.h>

There don't appear to be any users of ep93xx_gpio_int_debounce anyway.
But with the above mentioned changes:

Acked-by: Ryan Mallon <ryan at bluewatersys.com>

-- 
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