diff --git a/Documentation/devicetree/bindings/mfd/mfd.txt b/Documentation/devicetree/bindings/mfd/mfd.txt
index f1fceeda12f1..bcb6abb9d413 100644
--- a/Documentation/devicetree/bindings/mfd/mfd.txt
+++ b/Documentation/devicetree/bindings/mfd/mfd.txt
@@ -25,6 +25,16 @@ Optional properties:
   be used. In the latter case the child devices will be determined by the
   operating system.
 
+- ranges: Describes the address mapping relationship to the parent. Should set
+  the child's base address to 0, the physical address within parent's address
+  space, and the length of the address map.
+
+- #address-cells: Specifies the number of cells used to represent physical base
+  addresses. Must be present if ranges is used.
+
+- #size-cells: Specifies the number of cells used to represent the size of an
+  address. Must be present if ranges is used.
+
 Example:
 
 foo@1000 {