[PATCH net 04/12] net: systemport: Fix missing phy-handle parsing for non-fixed PHYs

[Florian Fainelli]

In bcm_sysport_probe(), priv->phy_dn is only initialized if the device
tree node has a fixed-link configuration (of_phy_is_fixed_link). When
connecting to a discrete MDIO-attached PHY referenced via 'phy-handle',
priv->phy_dn remains NULL. This causes of_phy_connect() during
bcm_sysport_open() to fail with -ENODEV since of_phy_find_device(NULL)
returns NULL.

Fix this by parsing 'phy-handle' via of_parse_phandle() and falling back
to of_phy_is_fixed_link(). Ensure proper of_node_get() and of_node_put()
refcounting lifecycle on both error unwinding and module remove paths.

Fixes: 186534a3f832 ("net: systemport: use the new fixed PHY helpers")
Assisted-by: LLM
Signed-off-by: Florian Fainelli <florian.fainelli@xxxxxxxxxxxx>
---
 drivers/net/ethernet/broadcom/bcmsysport.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bcmsysport.c b/drivers/net/ethernet/broadcom/bcmsysport.c
index b91a57540f55..78b96b192185 100644
--- a/drivers/net/ethernet/broadcom/bcmsysport.c
+++ b/drivers/net/ethernet/broadcom/bcmsysport.c
@@ -2527,17 +2527,19 @@ static int bcm_sysport_probe(struct platform_device *pdev)
 	if (ret)
 		priv->phy_interface = PHY_INTERFACE_MODE_GMII;
 
+	priv->phy_dn = of_parse_phandle(dn, "phy-handle", 0);
+
 	/* In the case of a fixed PHY, the DT node associated
 	 * to the PHY is the Ethernet MAC DT node.
 	 */
-	if (of_phy_is_fixed_link(dn)) {
+	if (!priv->phy_dn && of_phy_is_fixed_link(dn)) {
 		ret = of_phy_register_fixed_link(dn);
 		if (ret) {
 			dev_err(&pdev->dev, "failed to register fixed PHY\n");
 			goto err_free_netdev;
 		}
 
-		priv->phy_dn = dn;
+		priv->phy_dn = of_node_get(dn);
 	}
 
 	/* Initialize netdevice members */
@@ -2622,6 +2624,7 @@ static int bcm_sysport_probe(struct platform_device *pdev)
 err_deregister_fixed_link:
 	if (of_phy_is_fixed_link(dn))
 		of_phy_deregister_fixed_link(dn);
+	of_node_put(priv->phy_dn);
 err_free_netdev:
 	free_netdev(dev);
 	return ret;
@@ -2640,6 +2643,7 @@ static void bcm_sysport_remove(struct platform_device *pdev)
 	unregister_netdev(dev);
 	if (of_phy_is_fixed_link(dn))
 		of_phy_deregister_fixed_link(dn);
+	of_node_put(priv->phy_dn);
 	free_netdev(dev);
 	dev_set_drvdata(&pdev->dev, NULL);
 }
-- 
2.34.1