[PATCH v2 3/4] dt-bindings: backlight: Add led-backlight binding

[Jean-Jacques Hiblot]

Add DT binding for led-backlight.

Signed-off-by: Jean-Jacques Hiblot <jjhiblot@xxxxxx>
---
 .../bindings/leds/backlight/led-backlight.txt | 29 +++++++++++++++++++
 1 file changed, 29 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/leds/backlight/led-backlight.txt

diff --git a/Documentation/devicetree/bindings/leds/backlight/led-backlight.txt b/Documentation/devicetree/bindings/leds/backlight/led-backlight.txt
new file mode 100644
index 000000000000..4f545316b288
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/backlight/led-backlight.txt
@@ -0,0 +1,29 @@
+led-backlight bindings
+
+This binding is used to describe a basic backlight device made of LEDs.
+It can also be used to describe a backlight device controlled by the output of
+a LED driver.
+
+Required properties:
+  - compatible: "led-backlight"
+  - leds: a list of LEDs
+
+Optional properties:
+  - brightness-levels: Array of distinct brightness levels. These
+                       are in the range from 0 to 255. The actual brightness
+                       level programmed in each LED will be adjusted based on
+                       its maximum brightness:
+                       led brightness = (level * maximum brightness) / 255
+
+  - default-brightness-level: The default brightness level (index into the
+                              array defined by the "brightness-levels" property).
+
+Example:
+
+	backlight {
+		compatible = "led-backlight";
+
+		leds = <&led1>, <&led2>;
+		brightness-levels = <0 4 8 16 32 64 128 255>;
+		default-brightness-level = <6>;
+	};
-- 
2.17.1