1* Samsung Exynos Interrupt Combiner Controller
2
3Samsung's Exynos4 architecture includes a interrupt combiner controller which
4can combine interrupt sources as a group and provide a single interrupt request
5for the group. The interrupt request from each group are connected to a parent
6interrupt controller, such as GIC in case of Exynos4210.
7
8The interrupt combiner controller consists of multiple combiners. Up to eight
9interrupt sources can be connected to a combiner. The combiner outputs one
10combined interrupt for its eight interrupt sources. The combined interrupt
11is usually connected to a parent interrupt controller.
12
13A single node in the device tree is used to describe the interrupt combiner
14controller module (which includes multiple combiners). A combiner in the
15interrupt controller module shares config/control registers with other
16combiners. For example, a 32-bit interrupt enable/disable config register
17can accommodate up to 4 interrupt combiners (with each combiner supporting
18up to 8 interrupt sources).
19
20Required properties:
21- compatible: should be "samsung,exynos4210-combiner".
22- interrupt-controller: Identifies the node as an interrupt controller.
23- #interrupt-cells: should be <2>. The meaning of the cells are
24	* First Cell: Combiner Group Number.
25	* Second Cell: Interrupt number within the group.
26- reg: Base address and size of interrupt combiner registers.
27- interrupts: The list of interrupts generated by the combiners which are then
28    connected to a parent interrupt controller. The format of the interrupt
29    specifier depends in the interrupt parent controller.
30
31Optional properties:
32- samsung,combiner-nr: The number of interrupt combiners supported. If this
33  property is not specified, the default number of combiners is assumed
34  to be 16.
35- interrupt-parent: pHandle of the parent interrupt controller, if not
36  inherited from the parent node.
37
38
39Example:
40
41	The following is a an example from the Exynos4210 SoC dtsi file.
42
43	combiner:interrupt-controller@10440000 {
44		compatible = "samsung,exynos4210-combiner";
45		interrupt-controller;
46		#interrupt-cells = <2>;
47		reg = <0x10440000 0x1000>;
48		interrupts = <0 0 0>, <0 1 0>, <0 2 0>, <0 3 0>,
49			     <0 4 0>, <0 5 0>, <0 6 0>, <0 7 0>,
50			     <0 8 0>, <0 9 0>, <0 10 0>, <0 11 0>,
51			     <0 12 0>, <0 13 0>, <0 14 0>, <0 15 0>;
52	};
53