ARM: sa1111: add sa1111_get_irq()

Add a helper function to get the irq number for a device.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
diff --git a/arch/arm/common/sa1111.c b/arch/arm/common/sa1111.c
index 7f232ce..3c722a4 100644
--- a/arch/arm/common/sa1111.c
+++ b/arch/arm/common/sa1111.c
@@ -1357,6 +1357,14 @@
 }
 EXPORT_SYMBOL(sa1111_disable_device);
 
+int sa1111_get_irq(struct sa1111_dev *sadev, unsigned num)
+{
+	if (num >= ARRAY_SIZE(sadev->irq))
+		return -EINVAL;
+	return sadev->irq[num];
+}
+EXPORT_SYMBOL_GPL(sa1111_get_irq);
+
 /*
  *	SA1111 "Register Access Bus."
  *