lp855x-backlight.yaml

  1# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
  2%YAML 1.2
  3---
  4$id: http://devicetree.org/schemas/leds/backlight/lp855x-backlight.yaml#
  5$schema: http://devicetree.org/meta-schemas/core.yaml#
  6
  7title: Texas Instruments LP855X backlight controllers
  8
  9maintainers:
 10  - Artur Weber <aweber.kernel@gmail.com>
 11
 12properties:
 13  compatible:
 14    enum:
 15      - ti,lp8550
 16      - ti,lp8551
 17      - ti,lp8552
 18      - ti,lp8553
 19      - ti,lp8555
 20      - ti,lp8556
 21      - ti,lp8557
 22
 23  reg:
 24    maxItems: 1
 25
 26  dev-ctrl:
 27    $ref: /schemas/types.yaml#/definitions/uint8
 28    description:
 29      Value of device control register. This is a device-specific value.
 30
 31  bl-name:
 32    $ref: /schemas/types.yaml#/definitions/string
 33    description: Backlight device name.
 34
 35  init-brt:
 36    $ref: /schemas/types.yaml#/definitions/uint8
 37    description: Initial value of backlight brightness.
 38
 39  power-supply:
 40    description: Regulator which controls the 3V rail.
 41
 42  enable-supply:
 43    description: Regulator which controls the EN/VDDIO input.
 44
 45  pwms:
 46    maxItems: 1
 47    description: |
 48      PWM channel to use for controlling the backlight; setting this
 49      enables the PWM-based backlight control mode.
 50
 51  pwm-names: true
 52
 53  pwm-period:
 54    $ref: /schemas/types.yaml#/definitions/uint32
 55    description:
 56      PWM period value. Deprecated; set the period value in the pwms
 57      property instead.
 58    deprecated: true
 59
 60patternProperties:
 61  "^rom-[0-9a-f]{2}h$":
 62    type: object
 63    description: Nodes containing the values of configuration registers.
 64    additionalProperties: false
 65    properties:
 66      rom-addr:
 67        $ref: /schemas/types.yaml#/definitions/uint8
 68        description: Register address of ROM area to be updated.
 69
 70      rom-val:
 71        $ref: /schemas/types.yaml#/definitions/uint8
 72        description: Value to write to the ROM register.
 73
 74required:
 75  - compatible
 76  - reg
 77  - dev-ctrl
 78
 79unevaluatedProperties: false
 80
 81examples:
 82  - |
 83    i2c {
 84        #address-cells = <1>;
 85        #size-cells = <0>;
 86
 87        backlight@2c {
 88            compatible = "ti,lp8555";
 89            reg = <0x2c>;
 90
 91            dev-ctrl = /bits/ 8 <0x00>;
 92
 93            pwms = <&pwm 0 10000>;
 94            pwm-names = "lp8555";
 95
 96            /* 4V OV, 4 output LED0 string enabled */
 97            rom-14h {
 98              rom-addr = /bits/ 8 <0x14>;
 99              rom-val = /bits/ 8 <0xcf>;
100            };
101
102            /* Heavy smoothing, 24ms ramp time step */
103            rom-15h {
104              rom-addr = /bits/ 8 <0x15>;
105              rom-val = /bits/ 8 <0xc7>;
106            };
107
108            /* 4 output LED1 string enabled */
109            rom-19h {
110              rom-addr = /bits/ 8 <0x19>;
111              rom-val = /bits/ 8 <0x0f>;
112            };
113        };
114    };
115  - |
116    i2c {
117        #address-cells = <1>;
118        #size-cells = <0>;
119
120        backlight@2c {
121            compatible = "ti,lp8556";
122            reg = <0x2c>;
123
124            bl-name = "lcd-bl";
125            dev-ctrl = /bits/ 8 <0x85>;
126            init-brt = /bits/ 8 <0x10>;
127        };
128      };
129  - |
130    i2c {
131        #address-cells = <1>;
132        #size-cells = <0>;
133
134        backlight@2c {
135            compatible = "ti,lp8557";
136            reg = <0x2c>;
137            enable-supply = <&backlight_vddio>;
138            power-supply = <&backlight_vdd>;
139
140            dev-ctrl = /bits/ 8 <0x41>;
141            init-brt = /bits/ 8 <0x0a>;
142
143            /* 4V OV, 4 output LED string enabled */
144            rom-14h {
145              rom-addr = /bits/ 8 <0x14>;
146              rom-val = /bits/ 8 <0xcf>;
147            };
148        };
149    };