summaryrefslogtreecommitdiffstats
path: root/Documentation/devicetree/bindings/leds/backlight/qcom-wled.yaml
blob: a8490781011d1b842ff393566777d35c735ae3c0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
%YAML 1.2
---
$id: http://devicetree.org/schemas/leds/backlight/qcom-wled.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#

title: Qualcomm Technologies, Inc. WLED driver

maintainers:
  - Bjorn Andersson <andersson@kernel.org>
  - Kiran Gunda <quic_kgunda@quicinc.com>

description: |
  WLED (White Light Emitting Diode) driver is used for controlling display
  backlight that is part of PMIC on Qualcomm Technologies, Inc. reference
  platforms. The PMIC is connected to the host processor via SPMI bus.

properties:
  compatible:
    enum:
      - qcom,pm8941-wled
      - qcom,pmi8950-wled
      - qcom,pmi8994-wled
      - qcom,pmi8998-wled
      - qcom,pm660l-wled
      - qcom,pm6150l-wled
      - qcom,pm8150l-wled

  reg:
    minItems: 1
    maxItems: 2

  default-brightness:
    description: |
      brightness value on boot.

  label: true

  max-brightness:
    description: |
      Maximum brightness level.

  qcom,cs-out:
    description: |
      enable current sink output.
      This property is supported only for WLED3.
    type: boolean

  qcom,cabc:
    description: |
      enable content adaptive backlight control.
    type: boolean

  qcom,ext-gen:
    description: |
      use externally generated modulator signal to dim.
      This property is supported only for WLED3.
    type: boolean

  qcom,current-limit:
    description: |
      mA; per-string current limit.
      This property is supported only for WLED3.
    $ref: /schemas/types.yaml#/definitions/uint32
    default: 20
    minimum: 0
    maximum: 25

  qcom,current-limit-microamp:
    description: |
      uA; per-string current limit.
    default: 25
    minimum: 0
    maximum: 30000
    multipleOf: 25

  qcom,current-boost-limit:
    description: |
      mA; boost current limit.
    $ref: /schemas/types.yaml#/definitions/uint32

  qcom,switching-freq:
    description: |
      kHz; switching frequency.
    $ref: /schemas/types.yaml#/definitions/uint32
    enum: [ 600, 640, 685, 738, 800, 872, 960, 1066, 1200, 1371, 1600, 1920,
            2400, 3200, 4800, 9600 ]

  qcom,ovp:
    description: |
      V; Over-voltage protection limit.
      This property is supported only for WLED3.
    $ref: /schemas/types.yaml#/definitions/uint32
    enum: [ 27, 29, 32, 35 ]
    default: 29

  qcom,ovp-millivolt:
    description: |
      Over-voltage protection limit. This property is for WLED4 only.
    $ref: /schemas/types.yaml#/definitions/uint32
    enum: [ 18100, 19600, 29600, 31100 ]
    default: 29600

  qcom,num-strings:
    description: |
      number of led strings attached.
    $ref: /schemas/types.yaml#/definitions/uint32

  qcom,enabled-strings:
    description: |
      Array of the WLED strings numbered from 0 to 3. Each
      string of leds are operated individually. Specify the
      list of strings used by the device. Any combination of
      led strings can be used.
    $ref: /schemas/types.yaml#/definitions/uint32-array
    minItems: 1
    maxItems: 4

  qcom,external-pfet:
    description: |
      Specify if external PFET control for short circuit
      protection is used. This property is supported only
      for WLED4.
    type: boolean

  qcom,auto-string-detection:
    description: |
      Enables auto-detection of the WLED string configuration.
      This feature is not supported for WLED3.
    type: boolean

  interrupts:
    minItems: 1
    items:
      - description: over voltage protection interrupt.
      - description: short circuit interrupt.

  interrupt-names:
    minItems: 1
    items:
      - const: ovp
      - const: short

  qcom,modulator-sel:
    description: |
      Selects the modulator used for brightness modulation.
      Allowed values are,
           0 - Modulator A
           1 - Modulator B
      This property is applicable only to WLED5 peripheral.
    $ref: /schemas/types.yaml#/definitions/uint32
    enum: [ 0, 1 ]
    default: 0

  qcom,cabc-sel:
    description: |
      Selects the CABC pin signal used for brightness modulation.
      Allowed values are,
           0 - CABC disabled
           1 - CABC 1
           2 - CABC 2
           3 - External signal (e.g. LPG) is used for dimming
      This property is applicable only to WLED5 peripheral.
    $ref: /schemas/types.yaml#/definitions/uint32
    enum: [ 0, 1, 2, 3 ]

allOf:
  - if:
      properties:
        compatible:
          contains:
            const: qcom,pm8941-wled

    then:
      properties:
        reg:
          maxItems: 1

        qcom,current-boost-limit:
          enum: [ 105, 385, 525, 805, 980, 1260, 1400, 1680 ]
          default: 805

        qcom,switching-freq:
          default: 1600

        qcom,num-strings:
          enum: [ 1, 2, 3 ]

        interrupts:
          maxItems: 1

        interrupt-names:
          maxItems: 1

    else:
      properties:
        reg:
          minItems: 2

        qcom,current-boost-limit:
          enum: [ 105, 280, 450, 620, 970, 1150, 1300, 1500 ]
          default: 970

        qcom,switching-freq:
          default: 800

        qcom,num-strings:
          enum: [ 1, 2, 3, 4 ]

        interrupts:
          minItems: 2

        interrupt-names:
          minItems: 2
  - if:
      properties:
        compatible:
          contains:
            enum:
              - qcom,pm8150l-wled

    then:
      properties:
        default-brightness:
          minimum: 0
          maximum: 32767

        max-brightness:
          minimum: 0
          maximum: 32767

    else:
      properties:
        default-brightness:
          minimum: 0
          maximum: 4095

        max-brightness:
          minimum: 0
          maximum: 4095

required:
  - compatible
  - reg
  - label

additionalProperties: false

examples:
  - |
    backlight@d800 {
        compatible = "qcom,pm8941-wled";
        reg = <0xd800 0x100>;
        label = "backlight";

        qcom,cs-out;
        qcom,current-limit = <20>;
        qcom,current-boost-limit = <805>;
        qcom,switching-freq = <1600>;
        qcom,ovp = <29>;
        qcom,num-strings = <2>;
        qcom,enabled-strings = <0 1>;
     };