1 Specifying wakeup capability for devices
2 ============================================
3
4 Any device nodes
5 ----------------
6 Nodes that describe devices which have wakeup capability may contain a
7 "wakeup-source" boolean property.
8
9 If the device is marked as a wakeup-source, interrupt wake capability depends
10 on the device specific "interrupt-names" property. If no interrupts are labeled
11 as wake capable, then it is up to the device to determine which interrupts can
12 wake the system.
13
14 However if a device has a dedicated interrupt as the wakeup source, then it
15 needs to specify/identify it using a device specific interrupt name. In such
16 cases only that interrupt can be used as a wakeup interrupt.
17
18 While various legacy interrupt names exist, new devices should use "wakeup" as
19 the canonical interrupt name.
20
21 List of legacy properties and respective binding document
22 ---------------------------------------------------------
23
24 1. "gpio-key,wakeup" Documentation/devicetree/bindings/input/gpio-keys{,-polled}.txt
25 2. "has-tpo" Documentation/devicetree/bindings/rtc/rtc-opal.txt
26 3. "linux,wakeup" Documentation/devicetree/bindings/input/gpio-matrix-keypad.txt
27 Documentation/devicetree/bindings/mfd/tc3589x.txt
28 Documentation/devicetree/bindings/input/touchscreen/ti,ads7843.yaml
29 4. "linux,keypad-wakeup" Documentation/devicetree/bindings/input/qcom,pm8921-keypad.yaml
30 5. "linux,input-wakeup" Documentation/devicetree/bindings/input/samsung,s3c6410-keypad.yaml
31 6. "nvidia,wakeup-source" Documentation/devicetree/bindings/input/nvidia,tegra20-kbc.txt
32
33 Examples
34 --------
35
36 1. With "wakeup" interrupt name
37
38 device@10000 {
39 compatible = "vendor,device-id";
40 reg = <0x10000 0x1000>;
41 interrupts = <0 19 4>, <0 21 4>, <0 22 4>;
42 interrupt-names = "ack", "err", "wakeup";
43 wakeup-source;
44 };
45
46 2. Without "wakeup" interrupt name
47
48 embedded-controller {
49 compatible = "google,cros-ec-i2c";
50 reg = <0x1e>;
51 interrupts = <6 0>;
52 interrupt-parent = <&gpx1>;
53 pinctrl-names = "default";
54 pinctrl-0 = <&ec_irq>;
55 wakeup-source;
56 };
57
58 3. Without interrupts
59
60 gpio_keys {
61 compatible = "gpio-keys";
62 #address-cells = <1>;
63 #size-cells = <0>;
64
65 button@1 {
66 debounce-interval = <50>;
67 wakeup-source;
68 linux,code = <116>;
69 label = "POWER";
70 gpios = <&iofpga_gpio0 0 0x4>;
71 };
72 [....]
73 };
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