Documentation/devicetree/bindings/leds/common.yaml - linux - Git at Google

 # SPDX-License-Identifier: GPL-2.0-only
 %YAML 1.2
 ---
 $id: http://devicetree.org/schemas/leds/common.yaml#
 $schema: http://devicetree.org/meta-schemas/core.yaml#

 title: Common leds properties

 maintainers:
   - Jacek Anaszewski <jacek.anaszewski@gmail.com>
   - Pavel Machek <pavel@ucw.cz>

 description:
   LED and flash LED devices provide the same basic functionality as current
   regulators, but extended with LED and flash LED specific features like
   blinking patterns, flash timeout, flash faults and external flash strobe mode.

   Many LED devices expose more than one current output that can be connected
   to one or more discrete LED component. Since the arrangement of connections
   can influence the way of the LED device initialization, the LED components
   have to be tightly coupled with the LED device binding. They are represented
   by child nodes of the parent LED device binding.

 properties:
   led-sources:
     description:
       List of device current outputs the LED is connected to. The outputs are
       identified by the numbers that must be defined in the LED device binding
       documentation.
     $ref: /schemas/types.yaml#/definitions/uint32-array

   function:
     description:
       LED function. Use one of the LED_FUNCTION_* prefixed definitions
       from the header include/dt-bindings/leds/common.h. If there is no
       matching LED_FUNCTION available, add a new one.
     $ref: /schemas/types.yaml#/definitions/string

   color:
     description:
       Color of the LED. Use one of the LED_COLOR_ID_* prefixed definitions from
       the header include/dt-bindings/leds/common.h. If there is no matching
       LED_COLOR_ID available, add a new one.
     $ref: /schemas/types.yaml#/definitions/uint32
     minimum: 0
     maximum: 14

   function-enumerator:
     description:
       Integer to be used when more than one instance of the same function is
       needed, differing only with an ordinal number.
     $ref: /schemas/types.yaml#/definitions/uint32

   label:
     description:
       The label for this LED. If omitted, the label is taken from the node name
       (excluding the unit address). It has to uniquely identify a device, i.e.
       no other LED class device can be assigned the same label. This property is
       deprecated - use 'function' and 'color' properties instead.
       function-enumerator has no effect when this property is present.

   default-state:
     description:
       The initial state of the LED. If the LED is already on or off and the
       default-state property is set the to same value, then no glitch should be
       produced where the LED momentarily turns off (or on). The "keep" setting
       will keep the LED at whatever its current state is, without producing a
       glitch.
     $ref: /schemas/types.yaml#/definitions/string
     enum:
       - on
       - off
       - keep
     default: off

   linux,default-trigger:
     description:
       This parameter, if present, is a string defining the trigger assigned to
       the LED.
     $ref: /schemas/types.yaml#/definitions/string

     oneOf:
       - enum:
             # LED will act as a back-light, controlled by the framebuffer system
           - backlight
             # LED will turn on (see also "default-state" property)
           - default-on
             # LED "double" flashes at a load average based rate
           - heartbeat
             # LED indicates disk activity
           - disk-activity
             # LED indicates disk read activity
           - disk-read
             # LED indicates disk write activity
           - disk-write
             # LED flashes at a fixed, configurable rate
           - timer
             # LED alters the brightness for the specified duration with one software
             # timer (requires "led-pattern" property)
           - pattern
             # LED indicates mic mute state
           - audio-micmute
             # LED indicates audio mute state
           - audio-mute
             # LED indicates bluetooth power state
           - bluetooth-power
             # LED indicates camera flash state
           - flash
             # LED indicated keyboard capslock
           - kbd-capslock
             # LED indicates MTD memory activity
           - mtd
             # LED indicates NAND memory activity (deprecated),
             # in new implementations use "mtd"
           - nand-disk
             # LED indicates network activity
           - netdev
             # No trigger assigned to the LED. This is the default mode
             # if trigger is absent
           - none
             # LED indicates camera torch state
           - torch
             # LED indicates USB gadget activity
           - usb-gadget
             # LED indicates USB host activity
           - usb-host
             # LED indicates USB port state
           - usbport
         # LED is triggered by CPU activity
       - pattern: "^cpu[0-9]*$"
         # LED is triggered by Bluetooth activity
       - pattern: "^hci[0-9]+-power$"
         # LED is triggered by SD/MMC activity
       - pattern: "^mmc[0-9]+$"
         # LED is triggered by WLAN activity
       - pattern: "^phy[0-9]+tx$"

   led-pattern:
     description: |
       Array of integers with default pattern for certain triggers.

       Each trigger may parse this property differently:
         - one-shot : two numbers specifying delay on and delay off (in ms),
         - timer : two numbers specifying delay on and delay off (in ms),
         - pattern : the pattern is given by a series of tuples, of
           brightness and duration (in ms).  The exact format is
           described in:
           Documentation/devicetree/bindings/leds/leds-trigger-pattern.txt
     $ref: /schemas/types.yaml#/definitions/uint32-matrix
     items:
       minItems: 2
       maxItems: 2

   led-max-microamp:
     description:
       Maximum LED supply current in microamperes. This property can be made
       mandatory for the board configurations introducing a risk of hardware
       damage in case an excessive current is set.
       For flash LED controllers with configurable current this property is
       mandatory for the LEDs in the non-flash modes (e.g. torch or indicator).

   max-brightness:
     description:
       Normally, the maximum brightness is determined by the hardware, and this
       property is not required. This property is used to set a software limit.
       It could happen that an LED is made so bright that it gets damaged or
       causes damage due to restrictions in a specific system, such as mounting
       conditions.
       Note that this flag is mainly used for PWM-LEDs, where it is not possible
       to map brightness to current. Drivers for other controllers should use
       led-max-microamp.
     $ref: /schemas/types.yaml#/definitions/uint32

   panic-indicator:
     description:
       This property specifies that the LED should be used, if at all possible,
       as a panic indicator.
     type: boolean

   retain-state-shutdown:
     description:
       This property specifies that the LED should not be turned off or changed
       when the system shuts down.
     type: boolean

   trigger-sources:
     description: |
       List of devices which should be used as a source triggering this LED
       activity. Some LEDs can be related to a specific device and should somehow
       indicate its state. E.g. USB 2.0 LED may react to device(s) in a USB 2.0
       port(s).
       Another common example is switch or router with multiple Ethernet ports
       each of them having its own LED assigned (assuming they are not
       hardwired). In such cases this property should contain phandle(s) of
       related source device(s).
       Another example is a GPIO line that will be monitored and mirror the
       state of the line (with or without inversion flags) to the LED.
       In many cases LED can be related to more than one device (e.g. one USB LED
       vs. multiple USB ports). Each source should be represented by a node in
       the device tree and be referenced by a phandle and a set of phandle
       arguments. A length of arguments should be specified by the
       #trigger-source-cells property in the source node.
     $ref: /schemas/types.yaml#/definitions/phandle-array

   active-low:
     type: boolean
     description:
       Makes LED active low. To turn the LED ON, line needs to be
       set to low voltage instead of high.

   inactive-high-impedance:
     type: boolean
     description:
       Set LED to high-impedance mode to turn the LED OFF. LED might also
       describe this mode as tristate.

   # Required properties for flash LED child nodes:
   flash-max-microamp:
     description:
       Maximum flash LED supply current in microamperes. Required for flash LED
       nodes with configurable current.

   flash-max-timeout-us:
     description:
       Maximum timeout in microseconds after which the flash LED is turned off.
       Required for flash LED nodes with configurable timeout.

 additionalProperties: true

 examples:
   - |
     #include <dt-bindings/gpio/gpio.h>
     #include <dt-bindings/leds/common.h>

     led-controller {
         compatible = "gpio-leds";

         led-0 {
             function = LED_FUNCTION_STATUS;
             linux,default-trigger = "heartbeat";
             gpios = <&gpio0 0 GPIO_ACTIVE_HIGH>;
         };

         led-1 {
             function = LED_FUNCTION_USB;
             gpios = <&gpio0 1 GPIO_ACTIVE_HIGH>;
             trigger-sources = <&ohci_port1>, <&ehci_port1>;
         };
     };

   - |
     #include <dt-bindings/leds/common.h>

     led-controller {
         compatible = "maxim,max77693-led";

         led {
             function = LED_FUNCTION_FLASH;
             color = <LED_COLOR_ID_WHITE>;
             led-sources = <0>, <1>;
             led-max-microamp = <50000>;
             flash-max-microamp = <320000>;
             flash-max-timeout-us = <500000>;
         };
     };

   - |
     #include <dt-bindings/leds/common.h>

     i2c {
         #address-cells = <1>;
         #size-cells = <0>;

         led-controller@30 {
             compatible = "panasonic,an30259a";
             reg = <0x30>;
             #address-cells = <1>;
             #size-cells = <0>;

             led@1 {
                 reg = <1>;
                 linux,default-trigger = "heartbeat";
                 function = LED_FUNCTION_INDICATOR;
                 function-enumerator = <1>;
             };

             led@2 {
                 reg = <2>;
                 function = LED_FUNCTION_INDICATOR;
                 function-enumerator = <2>;
             };

             led@3 {
                 reg = <3>;
                 function = LED_FUNCTION_INDICATOR;
                 function-enumerator = <3>;
             };
         };
     };

 ...
	# SPDX-License-Identifier: GPL-2.0-only
	%YAML 1.2
	---
	$id: http://devicetree.org/schemas/leds/common.yaml#
	$schema: http://devicetree.org/meta-schemas/core.yaml#

	title: Common leds properties

	maintainers:
	- Jacek Anaszewski <jacek.anaszewski@gmail.com>
	- Pavel Machek <pavel@ucw.cz>

	description:
	LED and flash LED devices provide the same basic functionality as current
	regulators, but extended with LED and flash LED specific features like
	blinking patterns, flash timeout, flash faults and external flash strobe mode.

	Many LED devices expose more than one current output that can be connected
	to one or more discrete LED component. Since the arrangement of connections
	can influence the way of the LED device initialization, the LED components
	have to be tightly coupled with the LED device binding. They are represented
	by child nodes of the parent LED device binding.

	properties:
	led-sources:
	description:
	List of device current outputs the LED is connected to. The outputs are
	identified by the numbers that must be defined in the LED device binding
	documentation.
	$ref: /schemas/types.yaml#/definitions/uint32-array

	function:
	description:
	LED function. Use one of the LED_FUNCTION_* prefixed definitions
	from the header include/dt-bindings/leds/common.h. If there is no
	matching LED_FUNCTION available, add a new one.
	$ref: /schemas/types.yaml#/definitions/string

	color:
	description:
	Color of the LED. Use one of the LED_COLOR_ID_* prefixed definitions from
	the header include/dt-bindings/leds/common.h. If there is no matching
	LED_COLOR_ID available, add a new one.
	$ref: /schemas/types.yaml#/definitions/uint32
	minimum: 0
	maximum: 14

	function-enumerator:
	description:
	Integer to be used when more than one instance of the same function is
	needed, differing only with an ordinal number.
	$ref: /schemas/types.yaml#/definitions/uint32

	label:
	description:
	The label for this LED. If omitted, the label is taken from the node name
	(excluding the unit address). It has to uniquely identify a device, i.e.
	no other LED class device can be assigned the same label. This property is
	deprecated - use 'function' and 'color' properties instead.
	function-enumerator has no effect when this property is present.

	default-state:
	description:
	The initial state of the LED. If the LED is already on or off and the
	default-state property is set the to same value, then no glitch should be
	produced where the LED momentarily turns off (or on). The "keep" setting
	will keep the LED at whatever its current state is, without producing a
	glitch.
	$ref: /schemas/types.yaml#/definitions/string
	enum:
	- on
	- off
	- keep
	default: off

	linux,default-trigger:
	description:
	This parameter, if present, is a string defining the trigger assigned to
	the LED.
	$ref: /schemas/types.yaml#/definitions/string

	oneOf:
	- enum:
	# LED will act as a back-light, controlled by the framebuffer system
	- backlight
	# LED will turn on (see also "default-state" property)
	- default-on
	# LED "double" flashes at a load average based rate
	- heartbeat
	# LED indicates disk activity
	- disk-activity
	# LED indicates disk read activity
	- disk-read
	# LED indicates disk write activity
	- disk-write
	# LED flashes at a fixed, configurable rate
	- timer
	# LED alters the brightness for the specified duration with one software
	# timer (requires "led-pattern" property)
	- pattern
	# LED indicates mic mute state
	- audio-micmute
	# LED indicates audio mute state
	- audio-mute
	# LED indicates bluetooth power state
	- bluetooth-power
	# LED indicates camera flash state
	- flash
	# LED indicated keyboard capslock
	- kbd-capslock
	# LED indicates MTD memory activity
	- mtd
	# LED indicates NAND memory activity (deprecated),
	# in new implementations use "mtd"
	- nand-disk
	# LED indicates network activity
	- netdev
	# No trigger assigned to the LED. This is the default mode
	# if trigger is absent
	- none
	# LED indicates camera torch state
	- torch
	# LED indicates USB gadget activity
	- usb-gadget
	# LED indicates USB host activity
	- usb-host
	# LED indicates USB port state
	- usbport
	# LED is triggered by CPU activity
	- pattern: "^cpu[0-9]*$"
	# LED is triggered by Bluetooth activity
	- pattern: "^hci[0-9]+-power$"
	# LED is triggered by SD/MMC activity
	- pattern: "^mmc[0-9]+$"
	# LED is triggered by WLAN activity
	- pattern: "^phy[0-9]+tx$"

	led-pattern:
	description: \|
	Array of integers with default pattern for certain triggers.

	Each trigger may parse this property differently:
	- one-shot : two numbers specifying delay on and delay off (in ms),
	- timer : two numbers specifying delay on and delay off (in ms),
	- pattern : the pattern is given by a series of tuples, of
	brightness and duration (in ms). The exact format is
	described in:
	Documentation/devicetree/bindings/leds/leds-trigger-pattern.txt
	$ref: /schemas/types.yaml#/definitions/uint32-matrix
	items:
	minItems: 2
	maxItems: 2

	led-max-microamp:
	description:
	Maximum LED supply current in microamperes. This property can be made
	mandatory for the board configurations introducing a risk of hardware
	damage in case an excessive current is set.
	For flash LED controllers with configurable current this property is
	mandatory for the LEDs in the non-flash modes (e.g. torch or indicator).

	max-brightness:
	description:
	Normally, the maximum brightness is determined by the hardware, and this
	property is not required. This property is used to set a software limit.
	It could happen that an LED is made so bright that it gets damaged or
	causes damage due to restrictions in a specific system, such as mounting
	conditions.
	Note that this flag is mainly used for PWM-LEDs, where it is not possible
	to map brightness to current. Drivers for other controllers should use
	led-max-microamp.
	$ref: /schemas/types.yaml#/definitions/uint32

	panic-indicator:
	description:
	This property specifies that the LED should be used, if at all possible,
	as a panic indicator.
	type: boolean

	retain-state-shutdown:
	description:
	This property specifies that the LED should not be turned off or changed
	when the system shuts down.
	type: boolean

	trigger-sources:
	description: \|
	List of devices which should be used as a source triggering this LED
	activity. Some LEDs can be related to a specific device and should somehow
	indicate its state. E.g. USB 2.0 LED may react to device(s) in a USB 2.0
	port(s).
	Another common example is switch or router with multiple Ethernet ports
	each of them having its own LED assigned (assuming they are not
	hardwired). In such cases this property should contain phandle(s) of
	related source device(s).
	Another example is a GPIO line that will be monitored and mirror the
	state of the line (with or without inversion flags) to the LED.
	In many cases LED can be related to more than one device (e.g. one USB LED
	vs. multiple USB ports). Each source should be represented by a node in
	the device tree and be referenced by a phandle and a set of phandle
	arguments. A length of arguments should be specified by the
	#trigger-source-cells property in the source node.
	$ref: /schemas/types.yaml#/definitions/phandle-array

	active-low:
	type: boolean
	description:
	Makes LED active low. To turn the LED ON, line needs to be
	set to low voltage instead of high.

	inactive-high-impedance:
	type: boolean
	description:
	Set LED to high-impedance mode to turn the LED OFF. LED might also
	describe this mode as tristate.

	# Required properties for flash LED child nodes:
	flash-max-microamp:
	description:
	Maximum flash LED supply current in microamperes. Required for flash LED
	nodes with configurable current.

	flash-max-timeout-us:
	description:
	Maximum timeout in microseconds after which the flash LED is turned off.
	Required for flash LED nodes with configurable timeout.

	additionalProperties: true

	examples:
	- \|
	#include <dt-bindings/gpio/gpio.h>
	#include <dt-bindings/leds/common.h>

	led-controller {
	compatible = "gpio-leds";

	led-0 {
	function = LED_FUNCTION_STATUS;
	linux,default-trigger = "heartbeat";
	gpios = <&gpio0 0 GPIO_ACTIVE_HIGH>;
	};

	led-1 {
	function = LED_FUNCTION_USB;
	gpios = <&gpio0 1 GPIO_ACTIVE_HIGH>;
	trigger-sources = <&ohci_port1>, <&ehci_port1>;
	};
	};

	- \|
	#include <dt-bindings/leds/common.h>

	led-controller {
	compatible = "maxim,max77693-led";

	led {
	function = LED_FUNCTION_FLASH;
	color = <LED_COLOR_ID_WHITE>;
	led-sources = <0>, <1>;
	led-max-microamp = <50000>;
	flash-max-microamp = <320000>;
	flash-max-timeout-us = <500000>;
	};
	};

	- \|
	#include <dt-bindings/leds/common.h>

	i2c {
	#address-cells = <1>;
	#size-cells = <0>;

	led-controller@30 {
	compatible = "panasonic,an30259a";
	reg = <0x30>;
	#address-cells = <1>;
	#size-cells = <0>;

	led@1 {
	reg = <1>;
	linux,default-trigger = "heartbeat";
	function = LED_FUNCTION_INDICATOR;
	function-enumerator = <1>;
	};

	led@2 {
	reg = <2>;
	function = LED_FUNCTION_INDICATOR;
	function-enumerator = <2>;
	};

	led@3 {
	reg = <3>;
	function = LED_FUNCTION_INDICATOR;
	function-enumerator = <3>;
	};
	};
	};

	...