net: fec: register a fixed phy using fixed_phy_register_100fd if needed

In case of coldfire/5272 a fixed phy is used, which so far is created
by platform code, using fixed_phy_add(). This function has a number of
problems, therefore create a potentially needed fixed phy here, using
fixed_phy_register_100fd.

Note 1: This includes a small functional change, as coldfire/5272
created a fixed phy in half-duplex mode. Likely this was by mistake,
because the fec MAC is 100FD-capable, and connection is to a switch.

Note 2: Usage of phy_find_next() makes use of the fact that dev_id can
only be 0 or 1.

Due to lack of hardware, this is compile-tested only.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Link: https://patch.msgid.link/adf4dc5c-5fa3-4ae6-a75c-a73954dede73@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

2 files changed, 27 insertions, 26 deletions

diff --git a/drivers/net/ethernet/freescale/Kconfig b/drivers/net/ethernet/freescale/Kconfig
index bbef47c3480c..e2a591cf9601 100644
--- a/drivers/net/ethernet/freescale/Kconfig
+++ b/drivers/net/ethernet/freescale/Kconfig
@@ -28,6 +28,7 @@ config FEC
 	depends on PTP_1588_CLOCK_OPTIONAL
 	select CRC32
 	select PHYLIB
+	select FIXED_PHY if M5272
 	select PAGE_POOL
 	imply PAGE_POOL_STATS
 	imply NET_SELFTESTS
diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
index 024dd443bfbc..742f3e81cc7c 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -52,6 +52,7 @@
 #include <linux/of_net.h>
 #include <linux/phy.h>
 #include <linux/pinctrl/consumer.h>
+#include <linux/phy_fixed.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 #include <linux/prefetch.h>
@@ -2472,11 +2473,8 @@ static int fec_enet_parse_rgmii_delay(struct fec_enet_private *fep,
 static int fec_enet_mii_probe(struct net_device *ndev)
 {
 	struct fec_enet_private *fep = netdev_priv(ndev);
-	struct phy_device *phy_dev = NULL;
-	char mdio_bus_id[MII_BUS_ID_SIZE];
-	char phy_name[MII_BUS_ID_SIZE + 3];
-	int phy_id;
-	int dev_id = fep->dev_id;
+	struct phy_device *phy_dev;
+	int ret;
 
 	if (fep->phy_node) {
 		phy_dev = of_phy_connect(ndev, fep->phy_node,
@@ -2488,30 +2486,28 @@ static int fec_enet_mii_probe(struct net_device *ndev)
 		}
 	} else {
 		/* check for attached phy */
-		for (phy_id = 0; (phy_id < PHY_MAX_ADDR); phy_id++) {
-			if (!mdiobus_is_registered_device(fep->mii_bus, phy_id))
-				continue;
-			if (dev_id--)
-				continue;
-			strscpy(mdio_bus_id, fep->mii_bus->id, MII_BUS_ID_SIZE);
-			break;
-		}
+		phy_dev = phy_find_first(fep->mii_bus);
+		if (fep->dev_id && phy_dev)
+			phy_dev = phy_find_next(fep->mii_bus, phy_dev);
 
-		if (phy_id >= PHY_MAX_ADDR) {
+		if (!phy_dev) {
 			netdev_info(ndev, "no PHY, assuming direct connection to switch\n");
-			strscpy(mdio_bus_id, "fixed-0", MII_BUS_ID_SIZE);
-			phy_id = 0;
+			phy_dev = fixed_phy_register_100fd();
+			if (IS_ERR(phy_dev)) {
+				netdev_err(ndev, "could not register fixed PHY\n");
+				return PTR_ERR(phy_dev);
+			}
 		}
 
-		snprintf(phy_name, sizeof(phy_name),
-			 PHY_ID_FMT, mdio_bus_id, phy_id);
-		phy_dev = phy_connect(ndev, phy_name, &fec_enet_adjust_link,
-				      fep->phy_interface);
-	}
+		ret = phy_connect_direct(ndev, phy_dev, &fec_enet_adjust_link,
+					 fep->phy_interface);
+		if (ret) {
+			if (phy_is_pseudo_fixed_link(phy_dev))
+				fixed_phy_unregister(phy_dev);
+			netdev_err(ndev, "could not attach to PHY\n");
+			return ret;
+		}
 
-	if (IS_ERR(phy_dev)) {
-		netdev_err(ndev, "could not attach to PHY\n");
-		return PTR_ERR(phy_dev);
 	}
 
 	/* mask with MAC supported features */
@@ -3616,8 +3612,9 @@ static int
 fec_enet_close(struct net_device *ndev)
 {
 	struct fec_enet_private *fep = netdev_priv(ndev);
+	struct phy_device *phy_dev = ndev->phydev;
 
-	phy_stop(ndev->phydev);
+	phy_stop(phy_dev);
 
 	if (netif_device_present(ndev)) {
 		napi_disable(&fep->napi);
@@ -3625,7 +3622,10 @@ fec_enet_close(struct net_device *ndev)
 		fec_stop(ndev);
 	}
 
-	phy_disconnect(ndev->phydev);
+	phy_disconnect(phy_dev);
+
+	if (!fep->phy_node && phy_is_pseudo_fixed_link(phy_dev))
+		fixed_phy_unregister(phy_dev);
 
 	if (fep->quirks & FEC_QUIRK_ERR006687)
 		imx6q_cpuidle_fec_irqs_unused();