of_mdio: avoid MDIO bus removal when a PHY is missing

[ Upstream commit 95f566de0269a0c59fd6a737a147731302136429 ]

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@nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/of/of_mdio.c b/drivers/of/of_mdio.c
index 9825858..8c18192 100644 (file)
--- a/drivers/of/of_mdio.c
+++ b/drivers/of/of_mdio.c
@@ -228,7 +228,12 @@ 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;
        }
 
@@ -252,7 +257,7 @@ 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;
                        }
                }