[PATCH v2 06/12] backlight: Document consumers of backlight nodes

Add a small note that makes explicit that properties named 'backlight'
contain phandles to backlight nodes.

This is needed so that we can automatically extract dependencies on
backlight devices by assuming that a property with that name contains a
phandle to such a device.

Signed-off-by: Tomeu Vizoso <redacted>
---

Changes in v2:
- Document that consumers of backlight devices can use the 'backlight'
  property to hold a phandle to the backlight device.

 .../bindings/video/backlight/backlight.txt         | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/video/backlight/backlight.txt

diff --git a/Documentation/devicetree/bindings/video/backlight/backlight.txt b/Documentation/devicetree/bindings/video/backlight/backlight.txt
new file mode 100644
index 0000000..309949d
--- /dev/null
+++ b/Documentation/devicetree/bindings/video/backlight/backlight.txt

@@ -0,0 +1,22 @@
+Specifying backlight information for devices
+======================
+
+Backlight user nodes
+--------------------
+
+Nodes such as display panels that refer to backlight devices can do so by simply having a property named 'backlight' that contains a phandle to a backlight node.
+
+Example:
+
+	backlight: backlight {
+		compatible = "gpio-backlight";
+		gpios = <&gpio3 4 GPIO_ACTIVE_HIGH>;
+	};
+
+	[...]
+
+	panel: panel {
+		compatible = "cptt,claa101wb01";
+
+		backlight = <&backlight>;
+	};

-- 
2.4.1