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+Common i2c bus multiplexer/switch properties.
+
+An i2c bus multiplexer/switch will have several child busses that are
+numbered uniquely in a device dependent manner. The nodes for an i2c bus
+multiplexer/switch will have one child node for each child
+bus.
+
+Required properties:
+- #address-cells = <1>;
+- #size-cells = <0>;
+
+Required properties for child nodes:
+- #address-cells = <1>;
+- #size-cells = <0>;
+- reg : The sub-bus number.
+
+Optional properties for child nodes:
+- Other properties specific to the multiplexer/switch hardware.
+- Child nodes conforming to i2c bus binding
+
+
+Example :
+
+ /*
+ An NXP pca9548 8 channel I2C multiplexer at address 0x70
+ with two NXP pca8574 GPIO expanders attached, one each to
+ ports 3 and 4.
+ */
+
+ mux@70 {
+ compatible = "nxp,pca9548";
+ reg = <0x70>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ i2c@3 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ reg = <3>;
+
+ gpio1: gpio@38 {
+ compatible = "nxp,pca8574";
+ reg = <0x38>;
+ #gpio-cells = <2>;
+ gpio-controller;
+ };
+ };
+ i2c@4 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ reg = <4>;
+
+ gpio2: gpio@38 {
+ compatible = "nxp,pca8574";
+ reg = <0x38>;
+ #gpio-cells = <2>;
+ gpio-controller;
+ };
+ };
+ };