[ARM] 5324/2: ep93xx: support gpio interrupt debounce

Add debounce support for ep93xx gpio interrupts.

On the EP93xx, GPIO ports A, B, and F can be used to generate
interrupts. For each port, if interrupts are enabled, it is
possible to debouce the input signal. Debouncing is implemented
by passing the input signal through a 2-bit shift register clocked
by a 128Hz clock.

This patch adds a platform specific way to enable the debouce
feature for these input ports.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 2 insertions, 0 deletions

diff --git a/arch/arm/mach-ep93xx/include/mach/gpio.h b/arch/arm/mach-ep93xx/include/mach/gpio.h
index f7020414c5df..0a1498ae899a 100644
--- a/arch/arm/mach-ep93xx/include/mach/gpio.h
+++ b/arch/arm/mach-ep93xx/include/mach/gpio.h
@@ -99,6 +99,8 @@
 /* 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>