Signed-off-by: Peter Rosin <p...@axentia.se>
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 .../devicetree/bindings/i2c/i2c-mux-simple.txt     | 81 ++++++++++++++++++++++
 1 file changed, 81 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/i2c/i2c-mux-simple.txt

diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-simple.txt 
b/Documentation/devicetree/bindings/i2c/i2c-mux-simple.txt
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+Simple I2C Bus Mux
+
+This binding describes an I2C bus multiplexer that uses a mux controller
+from the mux subsystem to route the I2C signals.
+
+                                  .-----.  .-----.
+                                  | dev |  | dev |
+    .------------.                '-----'  '-----'
+    | SoC        |                   |        |
+    |            |          .--------+--------'
+    |   .------. |  .------+    child bus A, on MUX value set to 0
+    |   | I2C  |-|--| Mux  |
+    |   '------' |  '--+---+    child bus B, on MUX value set to 1
+    |   .------. |     |    '----------+--------+--------.
+    |   | MUX- | |     |               |        |        |
+    |   | Ctrl |-|-----+            .-----.  .-----.  .-----.
+    |   '------' |                  | dev |  | dev |  | dev |
+    '------------'                  '-----'  '-----'  '-----'
+
+Required properties:
+- compatible: i2c-mux-simple,mux-locked or i2c-mux-simple,parent-locked
+- i2c-parent: The phandle of the I2C bus that this multiplexer's master-side
+  port is connected to.
+- mux-controls: The phandle of the mux controller to use for operating the
+  mux.
+* Standard I2C mux properties. See i2c-mux.txt in this directory.
+* I2C child bus nodes. See i2c-mux.txt in this directory. The sub-bus number
+  is also the mux-controller state described in ../misc/mux-controller.txt
+
+For each i2c child node, an I2C child bus will be created. They will
+be numbered based on their order in the device tree.
+
+Whenever an access is made to a device on a child bus, the value set
+in the relevant node's reg property will be set as the state in the
+mux controller.
+
+Example:
+       mux: mux-controller {
+               compatible = "mux-gpio";
+               #mux-control-cells = <0>;
+
+               mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>,
+                           <&pioA 1 GPIO_ACTIVE_HIGH>;
+       };
+
+       i2c-mux {
+               compatible = "i2c-mux-simple,mux-locked";
+               i2c-parent = <&i2c1>;
+
+               mux-controls = <&mux>;
+
+               #address-cells = <1>;
+               #size-cells = <0>;
+
+               i2c@1 {
+                       reg = <1>;
+                       #address-cells = <1>;
+                       #size-cells = <0>;
+
+                       ssd1307: oled@3c {
+                               compatible = "solomon,ssd1307fb-i2c";
+                               reg = <0x3c>;
+                               pwms = <&pwm 4 3000>;
+                               reset-gpios = <&gpio2 7 1>;
+                               reset-active-low;
+                       };
+               };
+
+               i2c@3 {
+                       reg = <3>;
+                       #address-cells = <1>;
+                       #size-cells = <0>;
+
+                       pca9555: pca9555@20 {
+                               compatible = "nxp,pca9555";
+                               gpio-controller;
+                               #gpio-cells = <2>;
+                               reg = <0x20>;
+                       };
+               };
+       };
-- 
2.1.4

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