[PATCH 4.14 105/115] of_mdio: avoid MDIO bus removal when a PHY is missing

[Greg Kroah-Hartman]

4.14-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Madalin Bucur <madalin.bucur@xxxxxxx>


[ 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@xxxxxxx>
Reviewed-by: Andrew Lunn <andrew@xxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/of/of_mdio.c |    9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

--- a/drivers/of/of_mdio.c
+++ b/drivers/of/of_mdio.c
@@ -228,7 +228,12 @@ int of_mdiobus_register(struct mii_bus *
 			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 *
 
 			if (of_mdiobus_child_is_phy(child)) {
 				rc = of_mdiobus_register_phy(mdio, child, addr);
-				if (rc)
+				if (rc && rc != -ENODEV)
 					goto unregister;
 			}
 		}