The LAN7801 is designed exclusively for external PHYs (unlike the LAN7800/LAN7850 which have internal PHYs), but lan78xx_mdio_init() restricts PHY scanning to MDIO addresses 0-7 by setting phy_mask to ~(0xFF). This prevents discovery of external PHYs wired to addresses outside that range. One such case is the DP83TC814 100BASE-T1 PHY, which is typically configured at MDIO address 10 via PHYAD bootstrap pins and goes undetected with the current mask. Set phy_mask to 0 for the LAN7801 so that all 32 MDIO addresses are scanned during bus registration, allowing any external PHY to be discovered regardless of its address. Signed-off-by: Martin Pålsson --- drivers/net/usb/lan78xx.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/usb/lan78xx.c b/drivers/net/usb/lan78xx.c index 00397a807393..9d8f1ff7028d 100644 --- a/drivers/net/usb/lan78xx.c +++ b/drivers/net/usb/lan78xx.c @@ -2094,8 +2094,8 @@ static int lan78xx_mdio_init(struct lan78xx_net *dev) dev->mdiobus->phy_mask = ~(1 << 1); break; case ID_REV_CHIP_ID_7801_: - /* scan thru PHYAD[2..0] */ - dev->mdiobus->phy_mask = ~(0xFF); + /* scan all 32 MDIO addresses for external PHYs */ + dev->mdiobus->phy_mask = 0; break; } --- base-commit: ee5492fd88cfc079c19fbeac78e9e53b7f6c04f3 change-id: 20260214-lan78xx-phy-mask-fix-a4260de15a4c Best regards, -- Martin Pålsson