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: 47dd7a540b ("net: add support for STMicroelectronics Ethernet controllers.")
Signed-off-by: Andrew Halaney <ahalaney@redhat.com>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
Link: https://lore.kernel.org/r/20231212-b4-stmmac-handle-mdio-enodev-v2-1-600171acf79f@redhat.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Andrew Halaney 2023-12-12 16:18:33 -06:00 committed by Greg Kroah-Hartman
parent 2698050cff
commit bc786d6254

View file

@ -360,7 +360,11 @@ 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(dev, "Cannot register the MDIO bus\n");
goto bus_register_fail;
}