diff -ur linux-3.7.9/arch/powerpc/include/asm/cpm1.h linux/arch/powerpc/include/asm/cpm1.h
--- linux-3.7.9/arch/powerpc/include/asm/cpm1.h	2013-02-17 19:53:32.000000000 +0100
+++ linux/arch/powerpc/include/asm/cpm1.h	2012-11-03 03:18:35.000000000 +0100
@@ -560,6 +560,8 @@
 #define CPM_PIN_SECONDARY 2
 #define CPM_PIN_GPIO      4
 #define CPM_PIN_OPENDRAIN 8
+#define CPM_PIN_FALLEDGE  16
+#define CPM_PIN_ANYEDGE   0
 
 enum cpm_port {
 	CPM_PORTA,
diff -ur linux-3.7.9/arch/powerpc/sysdev/cpm1.c linux/arch/powerpc/sysdev/cpm1.c
--- linux-3.7.9/arch/powerpc/sysdev/cpm1.c	2013-02-17 19:53:32.000000000 +0100
+++ linux/arch/powerpc/sysdev/cpm1.c	2013-02-21 15:52:51.000000000 +0100
@@ -375,6 +375,10 @@
 			setbits16(&iop->odr_sor, pin);
 		else
 			clrbits16(&iop->odr_sor, pin);
+		if (flags & CPM_PIN_FALLEDGE)
+			setbits16(&iop->intr, pin);
+		else
+			clrbits16(&iop->intr, pin);
 	}
 }
 
@@ -526,6 +530,9 @@
 
 	/* shadowed data register to clear/set bits safely */
 	u16 cpdata;
+
+	/* IRQ associated with Pins when relevant */
+	int irq[16];
 };
 
 static inline struct cpm1_gpio16_chip *
@@ -581,6 +588,30 @@
 	spin_unlock_irqrestore(&cpm1_gc->lock, flags);
 }
 
+static int __cpm1_gpio16_to_irq(struct of_mm_gpio_chip *mm_gc,
+		unsigned int gpio)
+{
+	struct cpm1_gpio16_chip *cpm1_gc = to_cpm1_gpio16_chip(mm_gc);
+
+	return cpm1_gc->irq[gpio] ? cpm1_gc->irq[gpio] : -ENXIO;
+}
+
+static int cpm1_gpio16_to_irq(struct gpio_chip *gc, unsigned int gpio)
+{
+	struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
+	struct cpm1_gpio16_chip *cpm1_gc = to_cpm1_gpio16_chip(mm_gc);
+	unsigned long flags;
+	int ret;
+
+	spin_lock_irqsave(&cpm1_gc->lock, flags);
+
+	ret = __cpm1_gpio16_to_irq(mm_gc, gpio);
+
+	spin_unlock_irqrestore(&cpm1_gc->lock, flags);
+
+	return ret;
+}
+
 static int cpm1_gpio16_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
 {
 	struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
@@ -621,6 +652,7 @@
 	struct cpm1_gpio16_chip *cpm1_gc;
 	struct of_mm_gpio_chip *mm_gc;
 	struct gpio_chip *gc;
+	int i;
 
 	cpm1_gc = kzalloc(sizeof(*cpm1_gc), GFP_KERNEL);
 	if (!cpm1_gc)
@@ -628,6 +660,9 @@
 
 	spin_lock_init(&cpm1_gc->lock);
 
+	for (i = 0; i < 16; i++)
+		cpm1_gc->irq[i] = irq_of_parse_and_map(np, i);
+
 	mm_gc = &cpm1_gc->mm_gc;
 	gc = &mm_gc->gc;
 
@@ -637,6 +672,7 @@
 	gc->direction_output = cpm1_gpio16_dir_out;
 	gc->get = cpm1_gpio16_get;
 	gc->set = cpm1_gpio16_set;
+	gc->to_irq = cpm1_gpio16_to_irq;
 
 	return of_mm_gpiochip_add(np, mm_gc);
 }
diff -ur linux-3.7.9/kernel/irq/irqdomain.c linux/kernel/irq/irqdomain.c
--- linux-3.7.9/kernel/irq/irqdomain.c	2013-02-17 19:53:32.000000000 +0100
+++ linux/kernel/irq/irqdomain.c	2012-12-13 19:52:38.000000000 +0100
@@ -763,7 +763,8 @@
 	BUG_ON(domain->revmap_type != IRQ_DOMAIN_MAP_LINEAR);
 
 	/* Check revmap bounds; complain if exceeded */
-	if (WARN_ON(hwirq >= domain->revmap_data.linear.size))
+	/* 255 is a trick to allow UNDEF value in DTS */
+	if (hwirq == 255 || WARN_ON(hwirq >= domain->revmap_data.linear.size))
 		return 0;
 
 	return domain->revmap_data.linear.revmap[hwirq];