xref: /freebsd/sys/contrib/device-tree/Bindings/leds/backlight/mediatek,mt6370-backlight.yaml (revision aa1a8ff2d6dbc51ef058f46f3db5a8bb77967145) 
1# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2%YAML 1.2
3---
4$id: http://devicetree.org/schemas/leds/backlight/mediatek,mt6370-backlight.yaml#
5$schema: http://devicetree.org/meta-schemas/core.yaml#
6
7title: MediaTek MT6370 Backlight
8
9maintainers:
10  - ChiaEn Wu <chiaen_wu@richtek.com>
11
12description: |
13  This module is part of the MT6370 MFD device.
14  The MT6370 Backlight WLED driver supports up to a 29V output voltage for
15  4 channels of 8 series WLEDs. Each channel supports up to 30mA of current
16  capability with 2048 current steps (11 bits, only for MT6370/MT6371) or
17  16384 current steps (14 bits, only for MT6372) in exponential or linear
18  mapping curves.
19
20allOf:
21  - $ref: common.yaml#
22
23properties:
24  compatible:
25    enum:
26      - mediatek,mt6370-backlight
27      - mediatek,mt6372-backlight
28
29  default-brightness:
30    minimum: 0
31
32  max-brightness:
33    minimum: 0
34
35  enable-gpios:
36    description: External backlight 'enable' pin
37    maxItems: 1
38
39  mediatek,bled-pwm-enable:
40    description: |
41      Enable external PWM input for backlight dimming
42    type: boolean
43
44  mediatek,bled-pwm-hys-enable:
45    description: |
46      Enable the backlight input-hysteresis for PWM mode
47    type: boolean
48
49  mediatek,bled-pwm-hys-input-th-steps:
50    $ref: /schemas/types.yaml#/definitions/uint8
51    enum: [1, 4, 16, 64]
52    description: |
53      The selection of the upper and lower bounds threshold of backlight
54      PWM resolution. If we choose selection 64, the variation of PWM
55      resolution needs more than 64 steps.
56
57  mediatek,bled-ovp-shutdown:
58    description: |
59      Enable the backlight shutdown when OVP level triggered
60    type: boolean
61
62  mediatek,bled-ovp-microvolt:
63    enum: [17000000, 21000000, 25000000, 29000000]
64    description: |
65      Backlight OVP level selection.
66
67  mediatek,bled-ocp-shutdown:
68    description: |
69      Enable the backlight shutdown when OCP level triggered.
70    type: boolean
71
72  mediatek,bled-ocp-microamp:
73    enum: [900000, 1200000, 1500000, 1800000]
74    description: |
75      Backlight OC level selection.
76
77  mediatek,bled-exponential-mode-enable:
78    description: |
79      Enable the exponential mode of backlight brightness. If this property
80      is not enabled, the default is to use linear mode.
81    type: boolean
82
83  mediatek,bled-channel-use:
84    $ref: /schemas/types.yaml#/definitions/uint8
85    description: |
86      Backlight LED channel to be used.
87      Each bit mapping to:
88        - 0: CH4
89        - 1: CH3
90        - 2: CH2
91        - 3: CH1
92    minimum: 1
93    maximum: 15
94
95if:
96  properties:
97    compatible:
98      contains:
99        const: mediatek,mt6372-backlight
100
101then:
102  properties:
103    default-brightness:
104      maximum: 16384
105
106    max-brightness:
107      maximum: 16384
108
109else:
110  properties:
111    default-brightness:
112      maximum: 2048
113
114    max-brightness:
115      maximum: 2048
116
117required:
118  - compatible
119  - mediatek,bled-channel-use
120
121additionalProperties: false
122