4.19-stable review patch. If anyone has any objections, please let me know.
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From: Andrew Halaney ahalaney@redhat.com
[ 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 ahalaney@redhat.com Reviewed-by: Serge Semin fancer.lancer@gmail.com Link: https://lore.kernel.org/r/20231212-b4-stmmac-handle-mdio-enodev-v2-1-600171a... Signed-off-by: Paolo Abeni pabeni@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c @@ -360,7 +360,11 @@ int stmmac_mdio_register(struct net_devi 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; }