1# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) 2%YAML 1.2 3--- 4$id: http://devicetree.org/schemas/leds/backlight/qcom-wled.yaml# 5$schema: http://devicetree.org/meta-schemas/core.yaml# 6 7title: Qualcomm Technologies, Inc. WLED driver 8 9maintainers: 10 - Bjorn Andersson <bjorn.andersson@linaro.org> 11 - Kiran Gunda <kgunda@codeaurora.org> 12 13description: | 14 WLED (White Light Emitting Diode) driver is used for controlling display 15 backlight that is part of PMIC on Qualcomm Technologies, Inc. reference 16 platforms. The PMIC is connected to the host processor via SPMI bus. 17 18properties: 19 compatible: 20 enum: 21 - qcom,pm8941-wled 22 - qcom,pmi8950-wled 23 - qcom,pmi8994-wled 24 - qcom,pmi8998-wled 25 - qcom,pm660l-wled 26 - qcom,pm6150l-wled 27 - qcom,pm8150l-wled 28 29 reg: 30 minItems: 1 31 maxItems: 2 32 33 default-brightness: 34 description: | 35 brightness value on boot. 36 37 label: true 38 39 max-brightness: 40 description: | 41 Maximum brightness level. 42 43 qcom,cs-out: 44 description: | 45 enable current sink output. 46 This property is supported only for WLED3. 47 type: boolean 48 49 qcom,cabc: 50 description: | 51 enable content adaptive backlight control. 52 type: boolean 53 54 qcom,ext-gen: 55 description: | 56 use externally generated modulator signal to dim. 57 This property is supported only for WLED3. 58 type: boolean 59 60 qcom,current-limit: 61 description: | 62 mA; per-string current limit. 63 This property is supported only for WLED3. 64 $ref: /schemas/types.yaml#/definitions/uint32 65 default: 20 66 minimum: 0 67 maximum: 25 68 69 qcom,current-limit-microamp: 70 description: | 71 uA; per-string current limit. 72 default: 25 73 minimum: 0 74 maximum: 30000 75 multipleOf: 25 76 77 qcom,current-boost-limit: 78 description: | 79 mA; boost current limit. 80 $ref: /schemas/types.yaml#/definitions/uint32 81 82 qcom,switching-freq: 83 description: | 84 kHz; switching frequency. 85 $ref: /schemas/types.yaml#/definitions/uint32 86 enum: [ 600, 640, 685, 738, 800, 872, 960, 1066, 1200, 1371, 1600, 1920, 87 2400, 3200, 4800, 9600 ] 88 89 qcom,ovp: 90 description: | 91 V; Over-voltage protection limit. 92 This property is supported only for WLED3. 93 $ref: /schemas/types.yaml#/definitions/uint32 94 enum: [ 27, 29, 32, 35 ] 95 default: 29 96 97 qcom,ovp-millivolt: 98 description: | 99 Over-voltage protection limit. This property is for WLED4 only. 100 $ref: /schemas/types.yaml#/definitions/uint32 101 enum: [ 18100, 19600, 29600, 31100 ] 102 default: 29600 103 104 qcom,num-strings: 105 description: | 106 number of led strings attached. 107 $ref: /schemas/types.yaml#/definitions/uint32 108 109 qcom,enabled-strings: 110 description: | 111 Array of the WLED strings numbered from 0 to 3. Each 112 string of leds are operated individually. Specify the 113 list of strings used by the device. Any combination of 114 led strings can be used. 115 $ref: /schemas/types.yaml#/definitions/uint32-array 116 minItems: 1 117 maxItems: 4 118 119 qcom,external-pfet: 120 description: | 121 Specify if external PFET control for short circuit 122 protection is used. This property is supported only 123 for WLED4. 124 type: boolean 125 126 qcom,auto-string-detection: 127 description: | 128 Enables auto-detection of the WLED string configuration. 129 This feature is not supported for WLED3. 130 type: boolean 131 132 interrupts: 133 minItems: 1 134 items: 135 - description: over voltage protection interrupt. 136 - description: short circuit interrupt. 137 138 interrupt-names: 139 minItems: 1 140 items: 141 - const: ovp 142 - const: short 143 144 qcom,modulator-sel: 145 description: | 146 Selects the modulator used for brightness modulation. 147 Allowed values are, 148 0 - Modulator A 149 1 - Modulator B 150 This property is applicable only to WLED5 peripheral. 151 $ref: /schemas/types.yaml#/definitions/uint32 152 enum: [ 0, 1 ] 153 default: 0 154 155 qcom,cabc-sel: 156 description: | 157 Selects the CABC pin signal used for brightness modulation. 158 Allowed values are, 159 0 - CABC disabled 160 1 - CABC 1 161 2 - CABC 2 162 3 - External signal (e.g. LPG) is used for dimming 163 This property is applicable only to WLED5 peripheral. 164 $ref: /schemas/types.yaml#/definitions/uint32 165 enum: [ 0, 1, 2, 3 ] 166 167allOf: 168 - if: 169 properties: 170 compatible: 171 contains: 172 const: qcom,pm8941-wled 173 174 then: 175 properties: 176 reg: 177 maxItems: 1 178 179 qcom,current-boost-limit: 180 enum: [ 105, 385, 525, 805, 980, 1260, 1400, 1680 ] 181 default: 805 182 183 qcom,switching-freq: 184 default: 1600 185 186 qcom,num-strings: 187 enum: [ 1, 2, 3 ] 188 189 interrupts: 190 maxItems: 1 191 192 interrupt-names: 193 maxItems: 1 194 195 else: 196 properties: 197 reg: 198 minItems: 2 199 200 qcom,current-boost-limit: 201 enum: [ 105, 280, 450, 620, 970, 1150, 1300, 1500 ] 202 default: 970 203 204 qcom,switching-freq: 205 default: 800 206 207 qcom,num-strings: 208 enum: [ 1, 2, 3, 4 ] 209 210 interrupts: 211 minItems: 2 212 213 interrupt-names: 214 minItems: 2 215 - if: 216 properties: 217 compatible: 218 contains: 219 enum: 220 - qcom,pm8150l-wled 221 222 then: 223 properties: 224 default-brightness: 225 minimum: 0 226 maximum: 32767 227 228 max-brightness: 229 minimum: 0 230 maximum: 32767 231 232 else: 233 properties: 234 default-brightness: 235 minimum: 0 236 maximum: 4095 237 238 max-brightness: 239 minimum: 0 240 maximum: 4095 241 242required: 243 - compatible 244 - reg 245 - label 246 247additionalProperties: false 248 249examples: 250 - | 251 backlight@d800 { 252 compatible = "qcom,pm8941-wled"; 253 reg = <0xd800 0x100>; 254 label = "backlight"; 255 256 qcom,cs-out; 257 qcom,current-limit = <20>; 258 qcom,current-boost-limit = <805>; 259 qcom,switching-freq = <1600>; 260 qcom,ovp = <29>; 261 qcom,num-strings = <2>; 262 qcom,enabled-strings = <0 1>; 263 }; 264