Quelle  wakeup-source.txt   Sprache: Text

Specifying wakeup capability for devices
============================================

Any device nodes
----------------
Nodes that describe devices which have wakeup capability may contain a
"wakeup-source" boolean property.

If the device is marked as a wakeup-source, interrupt wake capability depends
on the device specific "interrupt-names" property. If no interrupts are labeled
as wake capable, then it is up to the device to determine which interrupts can
wake the system.

However if a device has a dedicated interrupt as the wakeup source, then it
needs to specify/identify it using a device specific interrupt name. In such
cases only that interrupt can be used as a wakeup interrupt.

While various legacy interrupt names exist, new devices should use "wakeup" as
the canonical interrupt name.

List of legacy properties and respective binding document
---------------------------------------------------------

1. "gpio-key,wakeup"  Documentation/devicetree/bindings/input/gpio-keys{,-polled}.txt
2. "has-tpo"   Documentation/devicetree/bindings/rtc/rtc-opal.txt
3. "linux,wakeup"  Documentation/devicetree/bindings/input/gpio-matrix-keypad.yaml
    Documentation/devicetree/bindings/mfd/tc3589x.txt
    Documentation/devicetree/bindings/input/touchscreen/ti,ads7843.yaml
4. "linux,keypad-wakeup" Documentation/devicetree/bindings/input/qcom,pm8921-keypad.yaml
5. "linux,input-wakeup"  Documentation/devicetree/bindings/input/samsung,s3c6410-keypad.yaml
6. "nvidia,wakeup-source" Documentation/devicetree/bindings/input/nvidia,tegra20-kbc.txt

Examples
--------

1. With "wakeup" interrupt name

 device@10000 {
  compatible = "vendor,device-id";
  reg  = <0x10000 0x1000>;
  interrupts = <0 19 4>, <0 21 4>, <0 22 4>;
  interrupt-names = "ack", "err", "wakeup";
  wakeup-source;
 };

2. Without "wakeup" interrupt name

 embedded-controller {
  compatible = "google,cros-ec-i2c";
  reg = <0x1e>;
  interrupts = <6 0>;
  interrupt-parent = <&gpx1>;
  pinctrl-names = "default";
  pinctrl-0 = <&ec_irq>;
  wakeup-source;
 };

3. Without interrupts

 gpio_keys {
  compatible = "gpio-keys";
  #address-cells = <1>;
  #size-cells = <0>;

  button@1 {
   debounce-interval = <50>;
   wakeup-source;
   linux,code = <116>;
   label = "POWER";
   gpios = <&iofpga_gpio0 0 0x4>;
  };
  [....]
 };