This is a note to let you know that I've just added the patch titled
net: stmmac: Handle disabled MDIO busses from devicetree
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
net-stmmac-handle-disabled-mdio-busses-from-devicetr.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 91556e5b636c3363071e47a621f006912508dc41
Author: Andrew Halaney <ahalaney@xxxxxxxxxx>
Date: Tue Dec 12 16:18:33 2023 -0600
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 <ahalaney@xxxxxxxxxx>
Reviewed-by: Serge Semin <fancer.lancer@xxxxxxxxx>
Link: https://lore.kernel.org/r/20231212-b4-stmmac-handle-mdio-enodev-v2-1-600171acf79f@xxxxxxxxxx
Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c
index 19694b3a1fb9e..94f731f1d936e 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c
@@ -489,7 +489,11 @@ 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;
}
