在这里：
https://github.com/raspberrypi/linux/blob/6137fb168c08bd8c41c8421bf26f09ed29479f08/arch/arm/boot/dts/bcm2712-rpi-5-b.dts#L447

pwr_button {‌
compatible = "gpio-keys";

pinctrl-names = "default";
pinctrl-0 = <&pwr_button_pins>;
status = "okay";

pwr_key: pwr {‌
label = "pwr_button";
// linux,code = <205>; // KEY_SUSPEND
linux,code = <116>; // KEY_POWER
gpios = <&gio 20 GPIO_ACTIVE_LOW>;
debounce-interval = <50>; // ms
};
};