From: Andrew Halaney Date: Tue, 12 Dec 2023 22:18:33 +0000 (-0600) Subject: net: stmmac: Handle disabled MDIO busses from devicetree X-Git-Tag: v6.6.17~1965 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=58c556661641c5ecbfc064067a31729d8d2c193d;p=platform%2Fkernel%2Flinux-rpi.git net: stmmac: Handle disabled MDIO busses from devicetree [ Upstream commit e23c0d21ce9234fbc31ece35663ababbb83f9347 ] Many hardware configurations have the MDIO bus disabled, and are instead using some other MDIO bus to talk to the MAC's phy. of_mdiobus_register() returns -ENODEV in this case. Let's handle it gracefully instead of failing to probe the MAC. Fixes: 47dd7a540b8a ("net: add support for STMicroelectronics Ethernet controllers.") Signed-off-by: Andrew Halaney Reviewed-by: Serge Semin Link: https://lore.kernel.org/r/20231212-b4-stmmac-handle-mdio-enodev-v2-1-600171acf79f@redhat.com Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin --- diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c index fa9e7e7..0542cfd 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c @@ -591,7 +591,11 @@ int stmmac_mdio_register(struct net_device *ndev) new_bus->parent = priv->device; err = of_mdiobus_register(new_bus, mdio_node); - if (err != 0) { + if (err == -ENODEV) { + err = 0; + dev_info(dev, "MDIO bus is disabled\n"); + goto bus_register_fail; + } else if (err) { dev_err_probe(dev, err, "Cannot register the MDIO bus\n"); goto bus_register_fail; }