CONFIG_OF_MDIO (not configurable)
modulename: of_mdio.ko
configname: CONFIG_OF_MDIO
Linux Kernel Configuration
└─>Device Drivers
└─>Device Tree and Open Firmware support
└─>OF_MDIO
In linux kernel since version 2.6.31 (release Date: 2009-09-09)
OpenFirmware MDIO bus (Ethernet PHY) accessors