1 Specifying interrupt information for devices 1 Specifying interrupt information for devices
2 ============================================ 2 ============================================
3 3
4 1) Interrupt client nodes 4 1) Interrupt client nodes
5 ------------------------- 5 -------------------------
6 6
7 Nodes that describe devices which generate int 7 Nodes that describe devices which generate interrupts must contain an
8 "interrupts" property, an "interrupts-extended 8 "interrupts" property, an "interrupts-extended" property, or both. If both are
9 present, the latter should take precedence; th 9 present, the latter should take precedence; the former may be provided simply
10 for compatibility with software that does not 10 for compatibility with software that does not recognize the latter. These
11 properties contain a list of interrupt specifi 11 properties contain a list of interrupt specifiers, one per output interrupt. The
12 format of the interrupt specifier is determine 12 format of the interrupt specifier is determined by the interrupt controller to
13 which the interrupts are routed; see section 2 13 which the interrupts are routed; see section 2 below for details.
14 14
15 Example: 15 Example:
16 interrupt-parent = <&intc1>; 16 interrupt-parent = <&intc1>;
17 interrupts = <5 0>, <6 0>; 17 interrupts = <5 0>, <6 0>;
18 18
19 The "interrupt-parent" property is used to spe 19 The "interrupt-parent" property is used to specify the controller to which
20 interrupts are routed and contains a single ph 20 interrupts are routed and contains a single phandle referring to the interrupt
21 controller node. This property is inherited, s 21 controller node. This property is inherited, so it may be specified in an
22 interrupt client node or in any of its parent 22 interrupt client node or in any of its parent nodes. Interrupts listed in the
23 "interrupts" property are always in reference 23 "interrupts" property are always in reference to the node's interrupt parent.
24 24
25 The "interrupts-extended" property is a specia 25 The "interrupts-extended" property is a special form; useful when a node needs
26 to reference multiple interrupt parents or a d 26 to reference multiple interrupt parents or a different interrupt parent than
27 the inherited one. Each entry in this property 27 the inherited one. Each entry in this property contains both the parent phandle
28 and the interrupt specifier. 28 and the interrupt specifier.
29 29
30 Example: 30 Example:
31 interrupts-extended = <&intc1 5 1>, <& 31 interrupts-extended = <&intc1 5 1>, <&intc2 1 0>;
32 32
33 2) Interrupt controller nodes 33 2) Interrupt controller nodes
34 ----------------------------- 34 -----------------------------
35 35
36 A device is marked as an interrupt controller 36 A device is marked as an interrupt controller with the "interrupt-controller"
37 property. This is a empty, boolean property. A 37 property. This is a empty, boolean property. An additional "#interrupt-cells"
38 property defines the number of cells needed to 38 property defines the number of cells needed to specify a single interrupt.
39 39
40 It is the responsibility of the interrupt cont 40 It is the responsibility of the interrupt controller's binding to define the
41 length and format of the interrupt specifier. 41 length and format of the interrupt specifier. The following two variants are
42 commonly used: 42 commonly used:
43 43
44 a) one cell 44 a) one cell
45 ----------- 45 -----------
46 The #interrupt-cells property is set to 1 an 46 The #interrupt-cells property is set to 1 and the single cell defines the
47 index of the interrupt within the controller 47 index of the interrupt within the controller.
48 48
49 Example: 49 Example:
50 50
51 vic: intc@10140000 { 51 vic: intc@10140000 {
52 compatible = "arm,versatile-vi 52 compatible = "arm,versatile-vic";
53 interrupt-controller; 53 interrupt-controller;
54 #interrupt-cells = <1>; 54 #interrupt-cells = <1>;
55 reg = <0x10140000 0x1000>; 55 reg = <0x10140000 0x1000>;
56 }; 56 };
57 57
58 sic: intc@10003000 { 58 sic: intc@10003000 {
59 compatible = "arm,versatile-si 59 compatible = "arm,versatile-sic";
60 interrupt-controller; 60 interrupt-controller;
61 #interrupt-cells = <1>; 61 #interrupt-cells = <1>;
62 reg = <0x10003000 0x1000>; 62 reg = <0x10003000 0x1000>;
63 interrupt-parent = <&vic>; 63 interrupt-parent = <&vic>;
64 interrupts = <31>; /* Cascaded 64 interrupts = <31>; /* Cascaded to vic */
65 }; 65 };
66 66
67 b) two cells 67 b) two cells
68 ------------ 68 ------------
69 The #interrupt-cells property is set to 2 an 69 The #interrupt-cells property is set to 2 and the first cell defines the
70 index of the interrupt within the controller 70 index of the interrupt within the controller, while the second cell is used
71 to specify any of the following flags: 71 to specify any of the following flags:
72 - bits[3:0] trigger type and level flags 72 - bits[3:0] trigger type and level flags
73 1 = low-to-high edge triggered 73 1 = low-to-high edge triggered
74 2 = high-to-low edge triggered 74 2 = high-to-low edge triggered
75 4 = active high level-sensitive 75 4 = active high level-sensitive
76 8 = active low level-sensitive 76 8 = active low level-sensitive
77 77
78 Example: 78 Example:
79 79
80 i2c@7000c000 { 80 i2c@7000c000 {
81 gpioext: gpio-adnp@41 { 81 gpioext: gpio-adnp@41 {
82 compatible = "ad,gpio- 82 compatible = "ad,gpio-adnp";
83 reg = <0x41>; 83 reg = <0x41>;
84 84
85 interrupt-parent = <&g 85 interrupt-parent = <&gpio>;
86 interrupts = <160 1>; 86 interrupts = <160 1>;
87 87
88 gpio-controller; 88 gpio-controller;
89 #gpio-cells = <1>; 89 #gpio-cells = <1>;
90 90
91 interrupt-controller; 91 interrupt-controller;
92 #interrupt-cells = <2> 92 #interrupt-cells = <2>;
93 93
94 nr-gpios = <64>; 94 nr-gpios = <64>;
95 }; 95 };
96 96
97 sx8634@2b { 97 sx8634@2b {
98 compatible = "smtc,sx8 98 compatible = "smtc,sx8634";
99 reg = <0x2b>; 99 reg = <0x2b>;
100 100
101 interrupt-parent = <&g 101 interrupt-parent = <&gpioext>;
102 interrupts = <3 0x8>; 102 interrupts = <3 0x8>;
103 103
104 #address-cells = <1>; 104 #address-cells = <1>;
105 #size-cells = <0>; 105 #size-cells = <0>;
106 106
107 threshold = <0x40>; 107 threshold = <0x40>;
108 sensitivity = <7>; 108 sensitivity = <7>;
109 }; 109 };
110 }; 110 };
111 111
112 3) Interrupt wakeup parent 112 3) Interrupt wakeup parent
113 -------------------------- 113 --------------------------
114 114
115 Some interrupt controllers in a SoC, are alway 115 Some interrupt controllers in a SoC, are always powered on and have a select
116 interrupts routed to them, so that they can wa 116 interrupts routed to them, so that they can wakeup the SoC from suspend. These
117 interrupt controllers do not fall into the cat 117 interrupt controllers do not fall into the category of a parent interrupt
118 controller and can be specified by the "wakeup 118 controller and can be specified by the "wakeup-parent" property and contain a
119 single phandle referring to the wakeup capable 119 single phandle referring to the wakeup capable interrupt controller.
120 120
121 Example: 121 Example:
122 wakeup-parent = <&pdc_intc>; 122 wakeup-parent = <&pdc_intc>;
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.