Commit | Line | Data |
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acc20979 TR |
1 | Specifying interrupt information for devices |
2 | ============================================ | |
3 | ||
4 | 1) Interrupt client nodes | |
5 | ------------------------- | |
6 | ||
a9ecdc0f FF |
7 | Nodes that describe devices which generate interrupts must contain an |
8 | "interrupts" property, an "interrupts-extended" property, or both. If both are | |
9 | present, the latter should take precedence; the former may be provided simply | |
10 | for compatibility with software that does not recognize the latter. These | |
11 | properties contain a list of interrupt specifiers, one per output interrupt. The | |
12 | format of the interrupt specifier is determined by the interrupt controller to | |
13 | which the interrupts are routed; see section 2 below for details. | |
79d97015 GL |
14 | |
15 | Example: | |
16 | interrupt-parent = <&intc1>; | |
17 | interrupts = <5 0>, <6 0>; | |
acc20979 TR |
18 | |
19 | The "interrupt-parent" property is used to specify the controller to which | |
20 | interrupts are routed and contains a single phandle referring to the interrupt | |
21 | controller node. This property is inherited, so it may be specified in an | |
79d97015 GL |
22 | interrupt client node or in any of its parent nodes. Interrupts listed in the |
23 | "interrupts" property are always in reference to the node's interrupt parent. | |
24 | ||
25 | The "interrupts-extended" property is a special form for use when a node needs | |
26 | to reference multiple interrupt parents. Each entry in this property contains | |
27 | both the parent phandle and the interrupt specifier. "interrupts-extended" | |
28 | should only be used when a device has multiple interrupt parents. | |
29 | ||
30 | Example: | |
31 | interrupts-extended = <&intc1 5 1>, <&intc2 1 0>; | |
32 | ||
acc20979 TR |
33 | 2) Interrupt controller nodes |
34 | ----------------------------- | |
35 | ||
36 | A device is marked as an interrupt controller with the "interrupt-controller" | |
37 | property. This is a empty, boolean property. An additional "#interrupt-cells" | |
38 | property defines the number of cells needed to specify a single interrupt. | |
39 | ||
40 | It is the responsibility of the interrupt controller's binding to define the | |
41 | length and format of the interrupt specifier. The following two variants are | |
42 | commonly used: | |
43 | ||
44 | a) one cell | |
45 | ----------- | |
46 | The #interrupt-cells property is set to 1 and the single cell defines the | |
47 | index of the interrupt within the controller. | |
48 | ||
49 | Example: | |
50 | ||
51 | vic: intc@10140000 { | |
52 | compatible = "arm,versatile-vic"; | |
53 | interrupt-controller; | |
54 | #interrupt-cells = <1>; | |
55 | reg = <0x10140000 0x1000>; | |
56 | }; | |
57 | ||
58 | sic: intc@10003000 { | |
59 | compatible = "arm,versatile-sic"; | |
60 | interrupt-controller; | |
61 | #interrupt-cells = <1>; | |
62 | reg = <0x10003000 0x1000>; | |
63 | interrupt-parent = <&vic>; | |
64 | interrupts = <31>; /* Cascaded to vic */ | |
65 | }; | |
66 | ||
67 | b) two cells | |
68 | ------------ | |
69 | The #interrupt-cells property is set to 2 and the first cell defines the | |
70 | index of the interrupt within the controller, while the second cell is used | |
71 | to specify any of the following flags: | |
72 | - bits[3:0] trigger type and level flags | |
73 | 1 = low-to-high edge triggered | |
74 | 2 = high-to-low edge triggered | |
75 | 4 = active high level-sensitive | |
76 | 8 = active low level-sensitive | |
77 | ||
78 | Example: | |
79 | ||
80 | i2c@7000c000 { | |
81 | gpioext: gpio-adnp@41 { | |
82 | compatible = "ad,gpio-adnp"; | |
83 | reg = <0x41>; | |
84 | ||
85 | interrupt-parent = <&gpio>; | |
86 | interrupts = <160 1>; | |
87 | ||
88 | gpio-controller; | |
89 | #gpio-cells = <1>; | |
90 | ||
91 | interrupt-controller; | |
92 | #interrupt-cells = <2>; | |
93 | ||
94 | nr-gpios = <64>; | |
95 | }; | |
96 | ||
97 | sx8634@2b { | |
98 | compatible = "smtc,sx8634"; | |
99 | reg = <0x2b>; | |
100 | ||
101 | interrupt-parent = <&gpioext>; | |
102 | interrupts = <3 0x8>; | |
103 | ||
104 | #address-cells = <1>; | |
105 | #size-cells = <0>; | |
106 | ||
107 | threshold = <0x40>; | |
108 | sensitivity = <7>; | |
109 | }; | |
110 | }; |