[PATCH 1/3] dt-bindings: leds: backlight: apple,dwi-bl: Add bindings for Apple DWI backlight

[Nick Chan]

Add the device tree bindings for backlight controllers attached via Apple
DWI 2-wire interface.

Signed-off-by: Nick Chan <towinchenmi@xxxxxxxxx>
---
 .../bindings/leds/backlight/apple,dwi-bl.yaml | 55 +++++++++++++++++++
 1 file changed, 55 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/leds/backlight/apple,dwi-bl.yaml

diff --git a/Documentation/devicetree/bindings/leds/backlight/apple,dwi-bl.yaml b/Documentation/devicetree/bindings/leds/backlight/apple,dwi-bl.yaml
new file mode 100644
index 000000000000..fa3789b0b043
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/backlight/apple,dwi-bl.yaml
@@ -0,0 +1,55 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/leds/backlight/apple,dwi.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Apple DWI 2-Wire Interface Backlight Controller
+
+maintainers:
+  - Nick Chan <towinchenmi@xxxxxxxxx>
+
+description: |
+  Apple SoCs contain a 2-wire interface called DWI. On some Apple iPhones,
+  iPads and iPod touches with a LCD display, 1-2 backlight controllers
+  are connected via DWI. Interfacing with DWI controls all backlight
+  controllers at the same time. As such, the backlight controllers are
+  treated as a single controller regardless of the underlying
+  configuration.
+
+properties:
+  compatible:
+    items:
+      - enum:
+          - apple,s5l8960x-dwi-bl
+          - apple,t7000-dwi-bl
+          - apple,s8000-dwi-bl
+          - apple,t8010-dwi-bl
+          - apple,t8015-dwi-bl
+      - const: apple,dwi-bl
+
+  reg:
+    maxItems: 1
+
+  power-domains:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - power-domains
+
+additionalProperties: false
+
+examples:
+  - |
+    soc {
+      #address-cells = <2>;
+      #size-cells = <2>;
+
+      dwi_bl: backlight@20e200010 {
+        compatible = "apple,s5l8960x-dwi-bl", "apple,dwi-bl";
+        reg = <0x2 0x0e200010 0 8>;
+        power-domains = <&ps_dwi>;
+      };
+    };
-- 
2.47.1