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




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Based on kernel version 3.15.4. Page generated on 2014-07-07 09:00 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 either an
8	"interrupts" property or an "interrupts-extended" property. These properties
9	contain a list of interrupt specifiers, one per output interrupt. The format of
10	the interrupt specifier is determined by the interrupt controller to which the
11	interrupts are routed; see section 2 below for details.
12	
13	  Example:
14		interrupt-parent = <&intc1>;
15		interrupts = <5 0>, <6 0>;
16	
17	The "interrupt-parent" property is used to specify the controller to which
18	interrupts are routed and contains a single phandle referring to the interrupt
19	controller node. This property is inherited, so it may be specified in an
20	interrupt client node or in any of its parent nodes. Interrupts listed in the
21	"interrupts" property are always in reference to the node's interrupt parent.
22	
23	The "interrupts-extended" property is a special form for use when a node needs
24	to reference multiple interrupt parents. Each entry in this property contains
25	both the parent phandle and the interrupt specifier. "interrupts-extended"
26	should only be used when a device has multiple interrupt parents.
27	
28	  Example:
29		interrupts-extended = <&intc1 5 1>, <&intc2 1 0>;
30	
31	A device node may contain either "interrupts" or "interrupts-extended", but not
32	both. If both properties are present, then the operating system should log an
33	error and use only the data in "interrupts".
34	
35	2) Interrupt controller nodes
36	-----------------------------
37	
38	A device is marked as an interrupt controller with the "interrupt-controller"
39	property. This is a empty, boolean property. An additional "#interrupt-cells"
40	property defines the number of cells needed to specify a single interrupt.
41	
42	It is the responsibility of the interrupt controller's binding to define the
43	length and format of the interrupt specifier. The following two variants are
44	commonly used:
45	
46	  a) one cell
47	  -----------
48	  The #interrupt-cells property is set to 1 and the single cell defines the
49	  index of the interrupt within the controller.
50	
51	  Example:
52	
53		vic: intc@10140000 {
54			compatible = "arm,versatile-vic";
55			interrupt-controller;
56			#interrupt-cells = <1>;
57			reg = <0x10140000 0x1000>;
58		};
59	
60		sic: intc@10003000 {
61			compatible = "arm,versatile-sic";
62			interrupt-controller;
63			#interrupt-cells = <1>;
64			reg = <0x10003000 0x1000>;
65			interrupt-parent = <&vic>;
66			interrupts = <31>; /* Cascaded to vic */
67		};
68	
69	  b) two cells
70	  ------------
71	  The #interrupt-cells property is set to 2 and the first cell defines the
72	  index of the interrupt within the controller, while the second cell is used
73	  to specify any of the following flags:
74	    - bits[3:0] trigger type and level flags
75	        1 = low-to-high edge triggered
76	        2 = high-to-low edge triggered
77	        4 = active high level-sensitive
78	        8 = active low level-sensitive
79	
80	  Example:
81	
82		i2c@7000c000 {
83			gpioext: gpio-adnp@41 {
84				compatible = "ad,gpio-adnp";
85				reg = <0x41>;
86	
87				interrupt-parent = <&gpio>;
88				interrupts = <160 1>;
89	
90				gpio-controller;
91				#gpio-cells = <1>;
92	
93				interrupt-controller;
94				#interrupt-cells = <2>;
95	
96				nr-gpios = <64>;
97			};
98	
99			sx8634@2b {
100				compatible = "smtc,sx8634";
101				reg = <0x2b>;
102	
103				interrupt-parent = <&gpioext>;
104				interrupts = <3 0x8>;
105	
106				#address-cells = <1>;
107				#size-cells = <0>;
108	
109				threshold = <0x40>;
110				sensitivity = <7>;
111			};
112		};
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