of/irq: create interrupts-extended property

The standard interrupts property in device tree can only handle
interrupts coming from a single interrupt parent. If a device is wired
to multiple interrupt controllers, then it needs to be attached to a
node with an interrupt-map property to demux the interrupt specifiers
which is confusing. It would be a lot easier if there was a form of the
interrupts property that allows for a separate interrupt phandle for
each interrupt specifier.

This patch does exactly that by creating a new interrupts-extended
property which reuses the phandle+arguments pattern used by GPIOs and
other core bindings.

Signed-off-by: Grant Likely <grant.likely@linaro.org>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Kumar Gala <galak@codeaurora.org>
[grant.likely: removed versatile platform hunks into separate patch]
Cc: Rob Herring <rob.herring@calxeda.com>
diff --git a/arch/arm/boot/dts/testcases/tests-interrupts.dtsi b/arch/arm/boot/dts/testcases/tests-interrupts.dtsi
index 6ecda71..560d6bf 100644
--- a/arch/arm/boot/dts/testcases/tests-interrupts.dtsi
+++ b/arch/arm/boot/dts/testcases/tests-interrupts.dtsi
@@ -27,6 +27,12 @@
 						<4 &test_intc2 15 16>;
 			};
 
+			test_intmap1: intmap1 {
+				#interrupt-cells = <2>;
+				#address-cells = <0>;
+				interrupt-map = <1 2 &test_intc0 15>;
+			};
+
 			interrupts0 {
 				interrupt-parent = <&test_intc0>;
 				interrupts = <1>, <2>, <3>, <4>;
@@ -36,6 +42,16 @@
 				interrupt-parent = <&test_intmap0>;
 				interrupts = <1>, <2>, <3>, <4>;
 			};
+
+			interrupts-extended0 {
+				interrupts-extended = <&test_intc0 1>,
+						      <&test_intc1 2 3 4>,
+						      <&test_intc2 5 6>,
+						      <&test_intmap0 1>,
+						      <&test_intmap0 2>,
+						      <&test_intmap0 3>,
+						      <&test_intmap1 1 2>;
+			};
 		};
 	};
 };