[PATCH v4 2/3] dt-bindings: backlight: add lm3630a bindings

[Brian Masney]

Add new backlight bindings for the TI LM3630A dual-string white LED.

Signed-off-by: Brian Masney <masneyb at onstation.org>
---
Rob: Since the common bindings aren't converted to the new JSON schema
yet, I'm not sure how to do led-sources here. I would expect that we'd
have the uint32-array on the common binding once it exists. I had to
add it here to keep 'make dt_binding_check' happy. I left the
description off though for that property since that'll come from common
once its converted.

Changes since v3:
- Add label. I didn't add a description for it since that'll come from
  the common properties once its converted.

Changes since v2:
- Update description of max-brightness
- Add description for reg
- Correct typo: s/tranisiton/transition
- add reg to control banks
- add additionalProperties

 .../leds/backlight/lm3630a-backlight.yaml     | 128 ++++++++++++++++++
 1 file changed, 128 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/leds/backlight/lm3630a-backlight.yaml

diff --git a/Documentation/devicetree/bindings/leds/backlight/lm3630a-backlight.yaml b/Documentation/devicetree/bindings/leds/backlight/lm3630a-backlight.yaml
new file mode 100644
index 000000000000..5067038ca637
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/backlight/lm3630a-backlight.yaml
@@ -0,0 +1,128 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/leds/backlight/lm3630a-backlight.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: TI LM3630A High-Efficiency Dual-String White LED
+
+maintainers:
+  - Lee Jones <lee.jones at linaro.org>
+  - Daniel Thompson <daniel.thompson at linaro.org>
+  - Jingoo Han <jingoohan1 at gmail.com>
+
+description: |
+  The LM3630A is a current-mode boost converter which supplies the power and
+  controls the current in up to two strings of 10 LEDs per string.
+  https://www.ti.com/product/LM3630A
+
+properties:
+  compatible:
+    const: ti,lm3630a
+
+  reg:
+    description: The I2C address of the device
+    maxItems: 1
+
+  ti,linear-mapping-mode:
+    description: |
+      Enable linear mapping mode. If disabled, then it will use exponential
+      mapping mode in which the ramp up/down appears to have a more uniform
+      transition to the human eye.
+    type: boolean
+
+required:
+  - compatible
+  - reg
+
+patternProperties:
+  "^led@[01]$":
+    type: object
+    description: |
+      Properties for a string of connected LEDs.
+
+    properties:
+      reg:
+        description: Control Bank
+        maxItems: 1
+        minimum: 0
+        maximum: 1
+
+      label:
+        maxItems: 1
+
+      led-sources:
+        allOf:
+          - $ref: /schemas/types.yaml#/definitions/uint32-array
+          - minItems: 1
+            maxItems: 2
+            items:
+              minimum: 0
+              maximum: 1
+
+      default-brightness:
+        description: Default brightness level on boot.
+        minimum: 0
+        maximum: 255
+
+      max-brightness:
+        description: Maximum brightness that is allowed during runtime.
+        minimum: 0
+        maximum: 255
+
+    required:
+      - reg
+
+    additionalProperties: false
+
+additionalProperties: false
+
+examples:
+  - |
+    i2c {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        lm3630a_bl at 38 {
+                compatible = "ti,lm3630a";
+                status = "ok";
+                reg = <0x38>;
+
+                #address-cells = <1>;
+                #size-cells = <0>;
+
+                led at 0 {
+                        reg = <0>;
+                        led-sources = <0 1>;
+                        label = "lcd-backlight";
+                        default-brightness = <200>;
+                        max-brightness = <255>;
+                };
+        };
+    };
+  - |
+    i2c {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        lm3630a_bl at 38 {
+                compatible = "ti,lm3630a";
+                status = "ok";
+                reg = <0x38>;
+
+                #address-cells = <1>;
+                #size-cells = <0>;
+
+                led at 0 {
+                        reg = <0>;
+                        default-brightness = <150>;
+                        ti,linear-mapping-mode;
+                };
+
+                led at 1 {
+                        reg = <1>;
+                        default-brightness = <225>;
+                        ti,linear-mapping-mode;
+                };
+        };
+    };
-- 
2.20.1