- the "ref" clock is used to get the rate of the clock provided to the
PHY module
+Optional properties:
+- vbus-supply: power-supply phandle for vbus power source
+
The first phandle argument in the PHY specifier identifies the PHY, its
meaning is compatible dependent. For the currently supported SoCs (Exynos 4210
and Exynos 4212) it is as follows: