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# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
%YAML 1.2
---
$id: http://devicetree.org/schemas/leds/backlight/lp855x-backlight.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#
title: Texas Instruments LP855X backlight controllers
maintainers:
- Artur Weber <aweber.kernel@gmail.com>
properties:
compatible:
enum:
- ti,lp8550
- ti,lp8551
- ti,lp8552
- ti,lp8553
- ti,lp8555
- ti,lp8556
- ti,lp8557
reg:
maxItems: 1
dev-ctrl:
$ref: /schemas/types.yaml#/definitions/uint8
description:
Value of device control register. This is a device-specific value.
bl-name:
$ref: /schemas/types.yaml#/definitions/string
description: Backlight device name.
init-brt:
$ref: /schemas/types.yaml#/definitions/uint8
description: Initial value of backlight brightness.
power-supply:
description: Regulator which controls the 3V rail.
enable-supply:
description: Regulator which controls the EN/VDDIO input.
pwms:
maxItems: 1
description: |
PWM channel to use for controlling the backlight; setting this
enables the PWM-based backlight control mode.
pwm-names: true
pwm-period:
$ref: /schemas/types.yaml#/definitions/uint32
description:
PWM period value. Deprecated; set the period value in the pwms
property instead.
deprecated: true
patternProperties:
"^rom-[0-9a-f]{2}h$":
type: object
description: Nodes containing the values of configuration registers.
additionalProperties: false
properties:
rom-addr:
$ref: /schemas/types.yaml#/definitions/uint8
description: Register address of ROM area to be updated.
rom-val:
$ref: /schemas/types.yaml#/definitions/uint8
description: Value to write to the ROM register.
required:
- compatible
- reg
- dev-ctrl
unevaluatedProperties: false
examples:
- |
i2c {
#address-cells = <1>;
#size-cells = <0>;
backlight@2c {
compatible = "ti,lp8555";
reg = <0x2c>;
dev-ctrl = /bits/ 8 <0x00>;
pwms = <&pwm 0 10000>;
pwm-names = "lp8555";
/* 4V OV, 4 output LED0 string enabled */
rom-14h {
rom-addr = /bits/ 8 <0x14>;
rom-val = /bits/ 8 <0xcf>;
};
/* Heavy smoothing, 24ms ramp time step */
rom-15h {
rom-addr = /bits/ 8 <0x15>;
rom-val = /bits/ 8 <0xc7>;
};
/* 4 output LED1 string enabled */
rom-19h {
rom-addr = /bits/ 8 <0x19>;
rom-val = /bits/ 8 <0x0f>;
};
};
};
- |
i2c {
#address-cells = <1>;
#size-cells = <0>;
backlight@2c {
compatible = "ti,lp8556";
reg = <0x2c>;
bl-name = "lcd-bl";
dev-ctrl = /bits/ 8 <0x85>;
init-brt = /bits/ 8 <0x10>;
};
};
- |
i2c {
#address-cells = <1>;
#size-cells = <0>;
backlight@2c {
compatible = "ti,lp8557";
reg = <0x2c>;
enable-supply = <&backlight_vddio>;
power-supply = <&backlight_vdd>;
dev-ctrl = /bits/ 8 <0x41>;
init-brt = /bits/ 8 <0x0a>;
/* 4V OV, 4 output LED string enabled */
rom-14h {
rom-addr = /bits/ 8 <0x14>;
rom-val = /bits/ 8 <0xcf>;
};
};
};
|
