Commit bc786d62 authored Dec 12, 2023 by Andrew Halaney Committed by Greg Kroah-Hartman Dec 20, 2023

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: 47dd7a54 ("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>

parent 2698050c

drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c

+5 −1

Original line number	Diff line number	Diff line
		@@ -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;
		}