S3C24XX: Add gpio_to_irq implementation

Add the necessary to_irq fields for the S3C24XX
GPIO banks that support IRQs.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>

Index: linux-2.6.26-quilt3/arch/arm/plat-s3c24xx/gpiolib.c
===================================================================
--- linux-2.6.26-quilt3.orig/arch/arm/plat-s3c24xx/gpiolib.c	2008-07-18 12:35:15.000000000 +0100
+++ linux-2.6.26-quilt3/arch/arm/plat-s3c24xx/gpiolib.c	2008-07-18 12:37:39.000000000 +0100
@@ -150,6 +150,19 @@ static int s3c24xx_gpiolib_banka_output(
 	return 0;
 }
 
+static int s3c24xx_gpiolib_bankf_toirq(struct gpio_chip *chip, unsigned offset)
+{
+	if (offset < 4)
+		return IRQ_EINT0 + offset;
+
+	return IRQ_EINT4 + (offset - 4);
+}
+
+static int s3c24xx_gpiolib_bankg_toirq(struct gpio_chip *chip, unsigned offset)
+{
+	return IRQ_EINT8 + offset;
+}
+
 
 struct s3c24xx_gpio_chip gpios[] = {
 	[0] = {
@@ -228,6 +241,7 @@ struct s3c24xx_gpio_chip gpios[] = {
 			.direction_output	= s3c24xx_gpiolib_output,
 			.set			= s3c24xx_gpiolib_set,
 			.get			= s3c24xx_gpiolib_get,
+			.to_irq			= s3c24xx_gpiolib_bankf_toirq,
 		},
 	},
 	[6] = {
@@ -241,6 +255,7 @@ struct s3c24xx_gpio_chip gpios[] = {
 			.direction_output	= s3c24xx_gpiolib_output,
 			.set			= s3c24xx_gpiolib_set,
 			.get			= s3c24xx_gpiolib_get,
+			.to_irq			= s3c24xx_gpiolib_bankg_toirq,
 		},
 	},
 };