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Documentation / devicetree / bindings / interrupt-controller / interrupts.txt




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Based on kernel version 3.9. Page generated on 2013-05-02 22:58 EST.

1	Specifying interrupt information for devices
2	============================================
3	
4	1) Interrupt client nodes
5	-------------------------
6	
7	Nodes that describe devices which generate interrupts must contain an
8	"interrupts" property. This property must contain a list of interrupt
9	specifiers, one per output interrupt. The format of the interrupt specifier is
10	determined by the interrupt controller to which the interrupts are routed; see
11	section 2 below for details.
12	
13	The "interrupt-parent" property is used to specify the controller to which
14	interrupts are routed and contains a single phandle referring to the interrupt
15	controller node. This property is inherited, so it may be specified in an
16	interrupt client node or in any of its parent nodes.
17	
18	2) Interrupt controller nodes
19	-----------------------------
20	
21	A device is marked as an interrupt controller with the "interrupt-controller"
22	property. This is a empty, boolean property. An additional "#interrupt-cells"
23	property defines the number of cells needed to specify a single interrupt.
24	
25	It is the responsibility of the interrupt controller's binding to define the
26	length and format of the interrupt specifier. The following two variants are
27	commonly used:
28	
29	  a) one cell
30	  -----------
31	  The #interrupt-cells property is set to 1 and the single cell defines the
32	  index of the interrupt within the controller.
33	
34	  Example:
35	
36		vic: intc@10140000 {
37			compatible = "arm,versatile-vic";
38			interrupt-controller;
39			#interrupt-cells = <1>;
40			reg = <0x10140000 0x1000>;
41		};
42	
43		sic: intc@10003000 {
44			compatible = "arm,versatile-sic";
45			interrupt-controller;
46			#interrupt-cells = <1>;
47			reg = <0x10003000 0x1000>;
48			interrupt-parent = <&vic>;
49			interrupts = <31>; /* Cascaded to vic */
50		};
51	
52	  b) two cells
53	  ------------
54	  The #interrupt-cells property is set to 2 and the first cell defines the
55	  index of the interrupt within the controller, while the second cell is used
56	  to specify any of the following flags:
57	    - bits[3:0] trigger type and level flags
58	        1 = low-to-high edge triggered
59	        2 = high-to-low edge triggered
60	        4 = active high level-sensitive
61	        8 = active low level-sensitive
62	
63	  Example:
64	
65		i2c@7000c000 {
66			gpioext: gpio-adnp@41 {
67				compatible = "ad,gpio-adnp";
68				reg = <0x41>;
69	
70				interrupt-parent = <&gpio>;
71				interrupts = <160 1>;
72	
73				gpio-controller;
74				#gpio-cells = <1>;
75	
76				interrupt-controller;
77				#interrupt-cells = <2>;
78	
79				nr-gpios = <64>;
80			};
81	
82			sx8634@2b {
83				compatible = "smtc,sx8634";
84				reg = <0x2b>;
85	
86				interrupt-parent = <&gpioext>;
87				interrupts = <3 0x8>;
88	
89				#address-cells = <1>;
90				#size-cells = <0>;
91	
92				threshold = <0x40>;
93				sensitivity = <7>;
94			};
95		};
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