diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index f9cacdfb516e..3fc3a30fe7ed 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -1643,6 +1643,32 @@ static void phy_del_port(struct phy_device *phydev, struct phy_port *port)
 	phydev->n_ports--;
 }
 
+static int phy_setup_sfp_port(struct phy_device *phydev)
+{
+	struct phy_port *port = phy_port_alloc();
+	int ret;
+
+	if (!port)
+		return -ENOMEM;
+
+	port->parent_type = PHY_PORT_PHY;
+	port->phy = phydev;
+
+	/* The PHY is a media converter, the port connected to the SFP cage
+	 * is a MII port.
+	 */
+	port->is_mii = true;
+
+	/* The port->supported and port->interfaces list will be populated
+	 * when attaching the port to the phydev.
+	 */
+	ret = phy_add_port(phydev, port);
+	if (ret)
+		phy_port_destroy(port);
+
+	return ret;
+}
+
 /**
  * phy_sfp_probe - probe for a SFP cage attached to this PHY device
  * @phydev: Pointer to phy_device
@@ -1664,6 +1690,10 @@ int phy_sfp_probe(struct phy_device *phydev,
 		ret = sfp_bus_add_upstream(bus, phydev, ops);
 		sfp_bus_put(bus);
 	}
+
+	if (!ret && phydev->sfp_bus)
+		ret = phy_setup_sfp_port(phydev);
+
 	return ret;
 }
 EXPORT_SYMBOL(phy_sfp_probe);
diff --git a/drivers/net/phy/phy_port.c b/drivers/net/phy/phy_port.c
index 70b3ecb8fb09..81e557aae0d6 100644
--- a/drivers/net/phy/phy_port.c
+++ b/drivers/net/phy/phy_port.c
@@ -131,6 +131,21 @@ void phy_port_update_supported(struct phy_port *port)
 				 __ETHTOOL_LINK_MODE_MASK_NBITS)
 			port->pairs = max_t(int, port->pairs,
 					    ethtool_linkmode_n_pairs(mode));
+
+	/* Serdes ports supported through SFP may not have any medium set,
+	 * as they will output PHY_INTERFACE_MODE_XXX modes. In that case, derive
+	 * the supported list based on these interfaces
+	 */
+	if (port->is_mii && !port->mediums) {
+		unsigned long interface, link_caps = 0;
+
+		/* Get each interface's caps */
+		for_each_set_bit(interface, port->interfaces,
+				 PHY_INTERFACE_MODE_MAX)
+			link_caps |= phy_caps_from_interface(interface);
+
+		phy_caps_linkmodes(link_caps, port->supported);
+	}
 }
 EXPORT_SYMBOL_GPL(phy_port_update_supported);