diff --git a/Documentation/devicetree/bindings/net/mdio-mux.txt b/Documentation/devicetree/bindings/net/mdio-mux.txt
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+++ b/Documentation/devicetree/bindings/net/mdio-mux.txt
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+Common MDIO bus multiplexer/switch properties.
+
+An MDIO bus multiplexer/switch will have several child busses that are
+numbered uniquely in a device dependent manner. The nodes for an MDIO
+bus multiplexer/switch will have one child node for each child bus.
+
+Required properties:
+- parent-bus : phandle to the parent MDIO bus.
Should probably be mdio-parent-bus
+
+Optional properties:
+- Other properties specific to the multiplexer/switch hardware.
+
+Required properties for child nodes:
+- #address-cells =<1>;
+- #size-cells =<0>;
+- cell-index : The sub-bus number.
What does sub-bus number mean?
[...]
+
+
+Example :
+
+int mdio_mux_probe(struct platform_device *pdev,
+ int (*switch_fn)(int cur, int desired, void *data),
+ void *data)
+{
+ struct device_node *parent_bus_node;
+ struct device_node *child_bus_node;
+ int r, n, ret_val;
+ struct mii_bus *parent_bus;
+ struct mdio_mux_parent_bus *pb;
+ struct mdio_mux_child_bus *cb;
+
+ if (!pdev->dev.of_node)
+ return -ENODEV;
+
+ parent_bus_node = of_parse_phandle(pdev->dev.of_node, "parent-bus", 0);
+
+ if (!parent_bus_node)
+ return -ENODEV;
+
+ parent_bus = of_mdio_find_bus(parent_bus_node);
So what happens if the parent bus probe happens after the mux probe?