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diff --git a/Documentation/devicetree/bindings/gpio/gpio-mm-lantiq.txt b/Documentation/devicetree/bindings/gpio/gpio-mm-lantiq.txt
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+Lantiq SoC External Bus memory mapped GPIO controller
+
+By attaching hardware latches to the EBU it is possible to create output
+only gpios. This driver configures a special memory address, which when
+written to outputs 16 bit to the latches.
+
+The node describing the memory mapped GPIOs needs to be a child of the node
+describing the "lantiq,localbus".
+
+Required properties:
+- compatible : Should be "lantiq,gpio-mm-lantiq"
+- reg : Address and length of the register set for the device
+- #gpio-cells : Should be two.  The first cell is the pin number and
+  the second cell is used to specify optional parameters (currently
+  unused).
+- gpio-controller : Marks the device node as a gpio controller.
+
+Optional properties:
+- lantiq,shadow : The default value that we shall assume as already set on the
+  shift register cascade.
+
+Example:
+
+localbus@0 {
+        #address-cells = <2>;
+        #size-cells = <1>;
+        ranges = <0 0 0x0 0x3ffffff /* addrsel0 */
+                1 0 0x4000000 0x4000010>; /* addsel1 */
+        compatible = "lantiq,localbus", "simple-bus";
+
+        gpio_mm0: gpio@4000000 {
+                compatible = "lantiq,gpio-mm";
+                reg = <1 0x0 0x10>;
+                gpio-controller;
+                #gpio-cells = <2>;
+                lantiq,shadow = <0x77f>
+        };
+}