[patch 2/7] dt: dtb version: document chosen/dtb-info node binding

[frowand.list@gmail.com (Frank Rowand)]

From: Frank Rowand <frank.rowand@sonymobile.com>

Add /chosen/dtb-node binding.

Signed-off-by: Frank Rowand <frank.rowand@sonymobile.com>
---
 Documentation/devicetree/bindings/chosen.txt |   37 +++++++++++

Index: b/Documentation/devicetree/bindings/chosen.txt
===================================================================
--- a/Documentation/devicetree/bindings/chosen.txt
+++ b/Documentation/devicetree/bindings/chosen.txt
@@ -46,6 +46,43 @@ on PowerPC "stdout" if "stdout-path" is
 should only use the "stdout-path" property.
 
 
+dtb-info node
+----------------
+
+Information that describes where the device tree blob (DTB) came from and the
+environment it was created in.
+
+This node is normally created by including arch/arm/boot/dts/skeleton.dtsi,
+which includes include/dt-bindings/version.dtsi.
+
+Properties:
+
+version
+	The version of the DTB.  This is analagous to the linux kernel version.
+
+	This is a format free field intended for human consumption.  User space
+	programs should not have any expections about this property.
+
+	The DTB number in this property is incremented each time a make that
+	creates one or more DTBs is invoked.  If the make creates multiple
+	DTBs then this number is only incremented once.
+
+	The DTB number is stored in file .version_dtb.
+
+version-linux
+	The version of the linux kernel most recently built in the source
+	control system that contains the source used to build the DTB.
+
+	The linux kernel version number is not incremented for a make that
+	creates a DTB.
+
+dtb-path
+	The build directory relative path of the DTB.
+
+dts-path
+	The absolute path of the .dts file compiled to create the DTB.
+
+
 Properties documented in other bindings
 ---------------------------------------
 #address-cells                          video/simple-framebuffer-sunxi.txt