+ /*
+ * The dual fec interfaces are not equivalent with enet-mac.
+ * Here are the differences:
+ *
+ * - fec0 supports MII & RMII modes while fec1 only supports RMII
+ * - fec0 acts as the 1588 time master while fec1 is slave
+ * - external phys can only be configured by fec0
+ *
+ * That is to say fec1 can not work independently. It only works
+ * when fec0 is working. The reason behind this design is that the
+ * second interface is added primarily for Switch mode.
+ *
+ * Because of the last point above, both phys are attached on fec0
+ * mdio interface in board design, and need to be configured by
+ * fec0 mii_bus.
+ */
+ if ((id_entry->driver_data & FEC_QUIRK_ENET_MAC) && pdev->id) {
+ /* fec1 uses fec0 mii_bus */
+ fep->mii_bus = fec0_mii_bus;
+ return 0;
+ }
+