[ARM] 4783/1: S3C24XX: Add s3c2410_gpio_getpull()

Add the call s3c2410_gpio_getpull() to return the
current state of the pin's pull-up.
Signed-off-by: NBen Dooks <ben-linux@fluff.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

arch/arm/plat-s3c24xx/gpio.c

@@ -122,6 +122,19 @@ void s3c2410_gpio_pullup(unsigned int pin, unsigned int to)
 
 EXPORT_SYMBOL(s3c2410_gpio_pullup);
 
+int s3c2410_gpio_getpull(unsigned int pin)
+{
+	void __iomem *base = S3C24XX_GPIO_BASE(pin);
+	unsigned long offs = S3C2410_GPIO_OFFSET(pin);
+
+	if (pin < S3C2410_GPIO_BANKB)
+		return -EINVAL;
+
+	return (__raw_readl(base + 0x08) & (1L << offs)) ? 1 : 0;
+}
+
+EXPORT_SYMBOL(s3c2410_gpio_getpull);
+
 void s3c2410_gpio_setpin(unsigned int pin, unsigned int to)
 {
 	void __iomem *base = S3C24XX_GPIO_BASE(pin);

include/asm-arm/arch-s3c2410/hardware.h

@@ -87,6 +87,18 @@ extern int s3c2410_gpio_irqfilter(unsigned int pin, unsigned int on,
 
 extern void s3c2410_gpio_pullup(unsigned int pin, unsigned int to);
 
+/* s3c2410_gpio_getpull
+ *
+ * Read the state of the pull-up on a given pin
+ *
+ * return:
+ *	< 0 => error code
+ *	  0 => enabled
+ *	  1 => disabled
+*/
+
+extern int s3c2410_gpio_getpull(unsigned int pin);
+
 extern void s3c2410_gpio_setpin(unsigned int pin, unsigned int to);
 
 extern unsigned int s3c2410_gpio_getpin(unsigned int pin);