Kernel-4.18.0-80.el8_leds-gpio

LEDs connected to GPIO lines

Required properties:

• compatible : should be “gpio-leds”.

Each LED is represented as a sub-node of the gpio-leds device. Each
node’s name represents the name of the corresponding LED.

LED sub-node properties:

• gpios : Should specify the LED’s GPIO, see “gpios property” in
  Documentation/devicetree/bindings/gpio/gpio.txt. Active low LEDs should be
  indicated using flags in the GPIO specifier.
• label : (optional)
  see Documentation/devicetree/bindings/leds/common.txt
• linux,default-trigger : (optional)
  see Documentation/devicetree/bindings/leds/common.txt
• default-state: (optional) The initial state of the LED.
  see Documentation/devicetree/bindings/leds/common.txt
• retain-state-suspended: (optional) The suspend state can be retained.Such
  as charge-led gpio.
• retain-state-shutdown: (optional) Retain the state of the LED on shutdown.
  Useful in BMC systems, for example when the BMC is rebooted while the host
  remains up.
• panic-indicator : (optional)
  see Documentation/devicetree/bindings/leds/common.txt

Examples:

#include <dt-bindings/gpio/gpio.h>

leds {
compatible = “gpio-leds”;
hdd {
label = “Disk Activity”;
gpios = <&mcu_pio 0 GPIO_ACTIVE_LOW>;
linux,default-trigger = “disk-activity”;
};

fault {
    gpios = <&mcu_pio 1 GPIO_ACTIVE_HIGH>;
    /* Keep LED on if BIOS detected hardware fault */
    default-state = "keep";
};

};

run-control {
compatible = “gpio-leds”;
red {
gpios = <&mpc8572 6 GPIO_ACTIVE_HIGH>;
default-state = “off”;
};
green {
gpios = <&mpc8572 7 GPIO_ACTIVE_HIGH>;
default-state = “on”;
};
};

leds {
compatible = “gpio-leds”;

charger-led {
    gpios = <&gpio1 2 GPIO_ACTIVE_HIGH>;
    linux,default-trigger = "max8903-charger-charging";
    retain-state-suspended;
};

};