Merge branch 'net-ftgmac100-support-fixed-link'

Tao Ren says:

====================
net: ftgmac100: support fixed link

The patch series adds fixed link support to ftgmac100 driver.

Patch #1 adds fixed link logic into ftgmac100 driver.

Patch #2 enables mac3 controller in Elbert dts: Elbert mac3 is connected
to the onboard switch BCM53134P's IMP_RGMII port directly (no PHY
between BMC MAC and BCM53134P).
====================

Link: https://lore.kernel.org/r/20220907054453.20016-1-rentao.bupt@gmail.comSigned-off-by: Paolo Abeni <pabeni@redhat.com>

arch/arm/boot/dts/aspeed-bmc-facebook-elbert.dts

@@ -183,3 +183,21 @@ imux31: i2c@7 {
 &i2c11 {
 	status = "okay";
 };
+
+/*
+ * BMC's "mac3" controller is connected to BCM53134P's IMP_RGMII port
+ * directly (fixed link, no PHY in between).
+ * Note: BMC's "mdio0" controller is connected to BCM53134P's MDIO
+ * interface, and the MDIO channel will be enabled in dts later, when
+ * BCM53134 is added to "bcm53xx" DSA driver.
+ */
+&mac3 {
+	status = "okay";
+	phy-mode = "rgmii";
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_rgmii4_default>;
+	fixed-link {
+		speed = <1000>;
+		full-duplex;
+	};
+};

drivers/net/ethernet/faraday/ftgmac100.c

@@ -1701,10 +1701,14 @@ static int ftgmac100_setup_mdio(struct net_device *netdev)
 
 static void ftgmac100_phy_disconnect(struct net_device *netdev)
 {
+	struct ftgmac100 *priv = netdev_priv(netdev);
+
 	if (!netdev->phydev)
 		return;
 
 	phy_disconnect(netdev->phydev);
+	if (of_phy_is_fixed_link(priv->dev->of_node))
+		of_phy_deregister_fixed_link(priv->dev->of_node);
 }
 
 static void ftgmac100_destroy_mdio(struct net_device *netdev)
@@ -1867,6 +1871,26 @@ static int ftgmac100_probe(struct platform_device *pdev)
 			err = -EINVAL;
 			goto err_phy_connect;
 		}
+	} else if (np && of_phy_is_fixed_link(np)) {
+		struct phy_device *phy;
+
+		err = of_phy_register_fixed_link(np);
+		if (err) {
+			dev_err(&pdev->dev, "Failed to register fixed PHY\n");
+			goto err_phy_connect;
+		}
+
+		phy = of_phy_get_and_connect(priv->netdev, np,
+					     &ftgmac100_adjust_link);
+		if (!phy) {
+			dev_err(&pdev->dev, "Failed to connect to fixed PHY\n");
+			of_phy_deregister_fixed_link(np);
+			err = -EINVAL;
+			goto err_phy_connect;
+		}
+
+		/* Display what we found */
+		phy_attached_info(phy);
 	} else if (np && of_get_property(np, "phy-handle", NULL)) {
 		struct phy_device *phy;