[PATCH net, v3] of_mdio: avoid MDIO bus removal when a PHY is missing

From: Madalin Bucur
Date: Tue Jan 09 2018 - 07:43:57 EST


If one of the child devices is missing the of_mdiobus_register_phy()
call will return -ENODEV. When a missing device is encountered the
registration of the remaining PHYs is stopped and the MDIO bus will
fail to register. Propagate all errors except ENODEV to avoid it.

Signed-off-by: Madalin Bucur <madalin.bucur@xxxxxxx>
---

v3: move if after else
v2: add an error print for the first change; the second place has
some noise already generated by the existing code

drivers/of/of_mdio.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/of/of_mdio.c b/drivers/of/of_mdio.c
index 3481e69..a327be1 100644
--- a/drivers/of/of_mdio.c
+++ b/drivers/of/of_mdio.c
@@ -231,7 +231,12 @@ int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
rc = of_mdiobus_register_phy(mdio, child, addr);
else
rc = of_mdiobus_register_device(mdio, child, addr);
- if (rc)
+
+ if (rc == -ENODEV)
+ dev_err(&mdio->dev,
+ "MDIO device at address %d is missing.\n",
+ addr);
+ else if (rc)
goto unregister;
}

@@ -255,7 +260,7 @@ int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)

if (of_mdiobus_child_is_phy(child)) {
rc = of_mdiobus_register_phy(mdio, child, addr);
- if (rc)
+ if (rc && rc != -ENODEV)
goto unregister;
}
}
--
2.1.0