lm3630a-backlight.yaml

  1# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
  2%YAML 1.2
  3---
  4$id: http://devicetree.org/schemas/leds/backlight/lm3630a-backlight.yaml#
  5$schema: http://devicetree.org/meta-schemas/core.yaml#
  6
  7title: TI LM3630A High-Efficiency Dual-String White LED
  8
  9maintainers:
 10  - Lee Jones <lee@kernel.org>
 11  - Daniel Thompson <daniel.thompson@linaro.org>
 12  - Jingoo Han <jingoohan1@gmail.com>
 13
 14description: |
 15  The LM3630A is a current-mode boost converter which supplies the power and
 16  controls the current in up to two strings of 10 LEDs per string.
 17  https://www.ti.com/product/LM3630A
 18
 19properties:
 20  compatible:
 21    const: ti,lm3630a
 22
 23  reg:
 24    maxItems: 1
 25
 26  '#address-cells':
 27    const: 1
 28
 29  '#size-cells':
 30    const: 0
 31
 32  enable-gpios:
 33    description: GPIO to use to enable/disable the backlight (HWEN pin).
 34    maxItems: 1
 35
 36required:
 37  - compatible
 38  - reg
 39  - '#address-cells'
 40  - '#size-cells'
 41
 42patternProperties:
 43  "^led@[01]$":
 44    type: object
 45    description: |
 46      Properties for a string of connected LEDs.
 47
 48    properties:
 49      reg:
 50        description: |
 51          The control bank that is used to program the two current sinks. The
 52          LM3630A has two control banks (A and B) and are represented as 0 or 1
 53          in this property. The two current sinks can be controlled
 54          independently with both banks, or bank A can be configured to control
 55          both sinks with the led-sources property.
 56        minimum: 0
 57        maximum: 1
 58
 59      label:
 60        maxItems: 1
 61
 62      led-sources:
 63        allOf:
 64          - minItems: 1
 65            maxItems: 2
 66            items:
 67              minimum: 0
 68              maximum: 1
 69
 70      default-brightness:
 71        description: Default brightness level on boot.
 72        minimum: 0
 73        maximum: 255
 74
 75      max-brightness:
 76        description: Maximum brightness that is allowed during runtime.
 77        minimum: 0
 78        maximum: 255
 79
 80      ti,linear-mapping-mode:
 81        description: |
 82          Enable linear mapping mode. If disabled, then it will use exponential
 83          mapping mode in which the ramp up/down appears to have a more uniform
 84          transition to the human eye.
 85        type: boolean
 86
 87    required:
 88      - reg
 89
 90    additionalProperties: false
 91
 92additionalProperties: false
 93
 94examples:
 95  - |
 96    #include <dt-bindings/gpio/gpio.h>
 97    i2c {
 98        #address-cells = <1>;
 99        #size-cells = <0>;
100
101        led-controller@38 {
102                compatible = "ti,lm3630a";
103                reg = <0x38>;
104                enable-gpios = <&gpio2 5 GPIO_ACTIVE_HIGH>;
105
106                #address-cells = <1>;
107                #size-cells = <0>;
108
109                led@0 {
110                        reg = <0>;
111                        led-sources = <0 1>;
112                        label = "lcd-backlight";
113                        default-brightness = <200>;
114                        max-brightness = <255>;
115                };
116        };
117    };
118  - |
119    i2c {
120        #address-cells = <1>;
121        #size-cells = <0>;
122
123        led-controller@38 {
124                compatible = "ti,lm3630a";
125                reg = <0x38>;
126
127                #address-cells = <1>;
128                #size-cells = <0>;
129
130                led@0 {
131                        reg = <0>;
132                        default-brightness = <150>;
133                        ti,linear-mapping-mode;
134                };
135
136                led@1 {
137                        reg = <1>;
138                        default-brightness = <225>;
139                        ti,linear-mapping-mode;
140                };
141        };
142    };