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# 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: Binding for Qualcomm Technologies, Inc. WLED driver
maintainers:
- Bjorn Andersson <bjorn.andersson@linaro.org>
- Kiran Gunda <kgunda@codeaurora.org>
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,pmi8998-wled
- qcom,pm660l-wled
- qcom,pm8150l-wled
reg:
maxItems: 1
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:
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:
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>;
};
|