From f1e2f0ce704e4a14e3f367d3b97d3dd2d8e183b7 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Martin=20P=C3=A5lsson?= Date: Wed, 18 Feb 2026 05:28:22 +0000 Subject: [PATCH] net: usb: lan78xx: scan all MDIO addresses on LAN7801 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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. Remove the restrictive phy_mask assignment for the LAN7801 so that the default mask of 0 applies, allowing all 32 MDIO addresses to be scanned during bus registration. Fixes: 02dc1f3d613d ("lan78xx: add LAN7801 MAC only support") Signed-off-by: Martin Pålsson Link: https://patch.msgid.link/0110019c6f388aff-98d99cf0-4425-4fff-b16b-dea5ad8fafe0-000000@eu-north-1.amazonses.com Signed-off-by: Jakub Kicinski --- drivers/net/usb/lan78xx.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/drivers/net/usb/lan78xx.c b/drivers/net/usb/lan78xx.c index 00397a807393..065588c9cfa6 100644 --- a/drivers/net/usb/lan78xx.c +++ b/drivers/net/usb/lan78xx.c @@ -2094,8 +2094,6 @@ 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); break; }