diff --git a/include/linux/irq.h b/include/linux/irq.h
index b48eae32dc61c05eb5afd83c1c6c23ab4d10b85f..6e59ac05ef2af46d9a285bb57d5f8a8b81ff3c97 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -58,6 +58,7 @@
 #define IRQ_NOREQUEST		0x04000000	/* IRQ cannot be requested */
 #define IRQ_NOAUTOEN		0x08000000	/* IRQ will not be enabled on request irq */
 #define IRQ_DELAYED_DISABLE	0x10000000	/* IRQ disable (masking) happens delayed. */
+#define IRQ_WAKEUP		0x20000000	/* IRQ triggers system wakeup */
 
 struct proc_dir_entry;
 
@@ -124,6 +125,7 @@ struct irq_chip {
  * @action:		the irq action chain
  * @status:		status information
  * @depth:		disable-depth, for nested irq_disable() calls
+ * @wake_depth:		enable depth, for multiple set_irq_wake() callers
  * @irq_count:		stats field to detect stalled irqs
  * @irqs_unhandled:	stats field for spurious unhandled interrupts
  * @lock:		locking for SMP
@@ -147,6 +149,7 @@ struct irq_desc {
 	unsigned int		status;		/* IRQ status */
 
 	unsigned int		depth;		/* nested irq disables */
+	unsigned int		wake_depth;	/* nested wake enables */
 	unsigned int		irq_count;	/* For detecting broken IRQs */
 	unsigned int		irqs_unhandled;
 	spinlock_t		lock;
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 4e461438e48bfe687f4ced338a0f2c69791fb33e..92be519eff26fe3fd467eb6ca0e3e063a36f50ce 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -137,16 +137,40 @@ EXPORT_SYMBOL(enable_irq);
  *	@irq:	interrupt to control
  *	@on:	enable/disable power management wakeup
  *
- *	Enable/disable power management wakeup mode
+ *	Enable/disable power management wakeup mode, which is
+ *	disabled by default.  Enables and disables must match,
+ *	just as they match for non-wakeup mode support.
+ *
+ *	Wakeup mode lets this IRQ wake the system from sleep
+ *	states like "suspend to RAM".
  */
 int set_irq_wake(unsigned int irq, unsigned int on)
 {
 	struct irq_desc *desc = irq_desc + irq;
 	unsigned long flags;
 	int ret = -ENXIO;
+	int (*set_wake)(unsigned, unsigned) = desc->chip->set_wake;
 
+	/* wakeup-capable irqs can be shared between drivers that
+	 * don't need to have the same sleep mode behaviors.
+	 */
 	spin_lock_irqsave(&desc->lock, flags);
-	if (desc->chip->set_wake)
+	if (on) {
+		if (desc->wake_depth++ == 0)
+			desc->status |= IRQ_WAKEUP;
+		else
+			set_wake = NULL;
+	} else {
+		if (desc->wake_depth == 0) {
+			printk(KERN_WARNING "Unbalanced IRQ %d "
+					"wake disable\n", irq);
+			WARN_ON(1);
+		} else if (--desc->wake_depth == 0)
+			desc->status &= ~IRQ_WAKEUP;
+		else
+			set_wake = NULL;
+	}
+	if (set_wake)
 		ret = desc->chip->set_wake(irq, on);
 	spin_unlock_irqrestore(&desc->lock, flags);
 	return ret;