[ARM] mv78xx0: implement GPIO and GPIO interrupt support

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Signed-off-by: Nicolas Pitre <nico@marvell.com>
diff --git a/arch/arm/mach-mv78xx0/irq.c b/arch/arm/mach-mv78xx0/irq.c
index 503e5d1..e273418 100644
--- a/arch/arm/mach-mv78xx0/irq.c
+++ b/arch/arm/mach-mv78xx0/irq.c
@@ -11,13 +11,42 @@
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/pci.h>
+#include <linux/irq.h>
+#include <asm/gpio.h>
 #include <mach/mv78xx0.h>
 #include <plat/irq.h>
 #include "common.h"
 
+static void gpio_irq_handler(unsigned int irq, struct irq_desc *desc)
+{
+	BUG_ON(irq < IRQ_MV78XX0_GPIO_0_7 || irq > IRQ_MV78XX0_GPIO_24_31);
+
+	orion_gpio_irq_handler((irq - IRQ_MV78XX0_GPIO_0_7) << 3);
+}
+
 void __init mv78xx0_init_irq(void)
 {
+	int i;
+
 	orion_irq_init(0, (void __iomem *)(IRQ_VIRT_BASE + IRQ_MASK_LOW_OFF));
 	orion_irq_init(32, (void __iomem *)(IRQ_VIRT_BASE + IRQ_MASK_HIGH_OFF));
 	orion_irq_init(64, (void __iomem *)(IRQ_VIRT_BASE + IRQ_MASK_ERR_OFF));
+
+	/*
+	 * Mask and clear GPIO IRQ interrupts.
+	 */
+	writel(0, GPIO_LEVEL_MASK(0));
+	writel(0, GPIO_EDGE_MASK(0));
+	writel(0, GPIO_EDGE_CAUSE(0));
+
+	for (i = IRQ_MV78XX0_GPIO_START; i < NR_IRQS; i++) {
+		set_irq_chip(i, &orion_gpio_irq_level_chip);
+		set_irq_handler(i, handle_level_irq);
+		irq_desc[i].status |= IRQ_LEVEL;
+		set_irq_flags(i, IRQF_VALID);
+	}
+	set_irq_chained_handler(IRQ_MV78XX0_GPIO_0_7, gpio_irq_handler);
+	set_irq_chained_handler(IRQ_MV78XX0_GPIO_8_15, gpio_irq_handler);
+	set_irq_chained_handler(IRQ_MV78XX0_GPIO_16_23, gpio_irq_handler);
+	set_irq_chained_handler(IRQ_MV78XX0_GPIO_24_31, gpio_irq_handler);
 }