MIPS: RB532: GPIO register offsets are relative to GPIOBASE

This patch fixes the wrong use of GPIO register offsets
in devices.c. To avoid further problems, use gpio_get_value
to return the NAND status instead of our own expanded code.

Also define the zero offset of the alternate function register to allow
consistent access.
Signed-off-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Phil Sutter <n0-1@freewrt.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/include/asm/mach-rc32434/rb.h

@@ -40,12 +40,14 @@
 #define BTCS		0x010040
 #define BTCOMPARE	0x010044
 #define GPIOBASE	0x050000
-#define GPIOCFG		0x050004
-#define GPIOD		0x050008
-#define GPIOILEVEL	0x05000C
-#define GPIOISTAT	0x050010
-#define GPIONMIEN	0x050014
-#define IMASK6		0x038038
+/* Offsets relative to GPIOBASE */
+#define GPIOFUNC	0x00
+#define GPIOCFG		0x04
+#define GPIOD		0x08
+#define GPIOILEVEL	0x0C
+#define GPIOISTAT	0x10
+#define GPIONMIEN	0x14
+#define IMASK6		0x38
 #define LO_WPX		(1 << 0)
 #define LO_ALE		(1 << 1)
 #define LO_CLE		(1 << 2)

arch/mips/rb532/devices.c

@@ -118,7 +118,7 @@ static struct platform_device cf_slot0 = {
 /* Resources and device for NAND */
 static int rb532_dev_ready(struct mtd_info *mtd)
 {
-	return readl(IDT434_REG_BASE + GPIOD) & GPIO_RDY;
+	return gpio_get_value(GPIO_RDY);
 }
 
 static void rb532_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)