[PATCH v2 2/4] backlight: rt4831: Adds DT binding document for Richtek RT4831 backlight

[cy_huang <u0084500@gmail.com>]

From: ChiYuan Huang <cy_huang@richtek.com>

Adds DT binding document for Richtek RT4831 backlight.

Signed-off-by: ChiYuan Huang <cy_huang@richtek.com>
---
 .../leds/backlight/richtek,rt4831-backlight.yaml   | 86 ++++++++++++++++++++++
 1 file changed, 86 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/leds/backlight/richtek,rt4831-backlight.yaml

diff --git a/Documentation/devicetree/bindings/leds/backlight/richtek,rt4831-backlight.yaml b/Documentation/devicetree/bindings/leds/backlight/richtek,rt4831-backlight.yaml
new file mode 100644
index 00000000..df1439a
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/backlight/richtek,rt4831-backlight.yaml
@@ -0,0 +1,86 @@
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/leds/backlight/richtek,rt4831-backlight.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Richtek RT4831 Backlight
+
+maintainers:
+  - ChiYuan Huang <cy_huang@richtek.com>
+
+description: |
+  RT4831 is a mutifunctional device that can provide power to the LCD display
+  and LCD backlight.
+
+  For the LCD backlight, it can provide four channel WLED driving capability.
+  Each channel driving current is up to 30mA
+
+  Datasheet is available at
+  https://www.richtek.com/assets/product_file/RT4831A/DS4831A-05.pdf
+
+properties:
+  compatible:
+    const: richtek,rt4831-backlight
+
+  default-brightness:
+    description: |
+      The default brightness that applied to the system on start-up.
+    $ref: /schemas/types.yaml#/definitions/uint32
+    minimum: 0
+    maximum: 2048
+
+  max-brightness:
+    description: |
+      The max brightness for the H/W limit
+    $ref: /schemas/types.yaml#/definitions/uint32
+    minimum: 0
+    maximum: 2048
+
+  richtek,pwm-enable:
+    description: |
+      Specify the backlight dimming following by PWM duty or by SW control.
+    type: boolean
+
+  richtek,bled-ovp-sel:
+    description: |
+      Backlight OVP level selection, currently support 17V/21V/25V/29V.
+    $ref: /schemas/types.yaml#/definitions/uint8
+    default: 1
+    minimum: 0
+    maximum: 3
+
+  richtek,channel-use:
+    description: |
+      Backlight LED channel to be used.
+      BIT 0/1/2/3 is used to indicate led channel 1/2/3/4 enable or disable.
+    $ref: /schemas/types.yaml#/definitions/uint8
+    minimum: 1
+    maximum: 15
+
+required:
+  - compatible
+  - richtek,channel-use
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/leds/rt4831-backlight.h>
+    i2c {
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+      rt4831@11 {
+        compatible = "richtek,rt4831";
+        reg = <0x11>;
+
+        backlight {
+          compatible = "richtek,rt4831-backlight";
+          default-brightness = <1024>;
+          max-brightness = <2048>;
+          richtek,bled-ovp-sel = /bits/ 8 <RT4831_BLOVPLVL_21V>;
+          richtek,channel-use = /bits/ 8 <RT4831_BLED_ALLCHEN>;
+        };
+      };
+    };
-- 
2.7.4