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

On 01/27/2011 12:59 PM, H Hartley Sweeten wrote:

On Wednesday, January 26, 2011 4:48 PM, Ryan Mallon wrote:

quoted

On 01/27/2011 12:22 PM, H Hartley Sweeten wrote:

quoted

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@visionengravers.com>
Cc: Ryan Mallon <redacted>

---

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?

The reason I left the original function it that it messes with the cached gpio_int_debounce
values.  Also, the 'debounce' feature is interrupt specific.  If the gpio pin is no enabled
as an interrupt the debounce has no effect.  As such I figured it was cleaner to leave it
in place.

That's a valid reason. It is fine as is.

~Ryan

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