Kernel-4.18.0-80.el8_wakeup-source

Specifying wakeup capability for devices

Any device nodes

Nodes that describe devices which has wakeup capability must contain an
“wakeup-source” boolean property.

Also, if device is marked as a wakeup source, then all the primary
interrupt(s) can be used as wakeup interrupt(s).

However if the devices have dedicated interrupt as the wakeup source
then they need to specify/identify the same using device specific
interrupt name. In such cases only that interrupt can be used as wakeup
interrupt.

List of legacy properties and respective binding document

1. “enable-sdio-wakeup” Documentation/devicetree/bindings/mmc/mmc.txt
2. “gpio-key,wakeup” Documentation/devicetree/bindings/input/gpio-keys{,-polled}.txt
3. “has-tpo” Documentation/devicetree/bindings/rtc/rtc-opal.txt
4. “linux,wakeup” Documentation/devicetree/bindings/input/gpio-matrix-keypad.txt

            Documentation/devicetree/bindings/mfd/tc3589x.txt
            Documentation/devicetree/bindings/input/touchscreen/ads7846.txt
   

5. “linux,keypad-wakeup” Documentation/devicetree/bindings/input/qcom,pm8xxx-keypad.txt
6. “linux,input-wakeup” Documentation/devicetree/bindings/input/samsung-keypad.txt
7. “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>;
    };
    [....]
   

   };