From: Madalin Bucur <madalin.bucur@nxp.com>
To: <andrew@lunn.ch>, <f.fainelli@gmail.com>, <davem@davemloft.net>
CC: <geert+renesas@glider.be>, <robh+dt@kernel.org>,
        <frowand.list@gmail.com>, <netdev@vger.kernel.org>,
        <devicetree@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        Madalin Bucur <madalin.bucur@nxp.com>
Subject: [PATCH net, v2] of_mdio: avoid MDIO bus removal when a PHY is missing
Date: Tue, 9 Jan 2018 10:33:39 +0200
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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>
---
v2: add an error print for the first change; the second place has
    some noise aleady generated by the exing code

 drivers/of/of_mdio.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/of/of_mdio.c b/drivers/of/of_mdio.c
index 3481e69..a249370 100644
--- a/drivers/of/of_mdio.c
+++ b/drivers/of/of_mdio.c
@@ -231,8 +231,14 @@ 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)
-			goto unregister;
+
+		if (rc == -ENODEV)
+			dev_err(&mdio->dev,
+				"MDIO device at address %d is missing.\n",
+				addr);
+		else
+			if (rc)
+				goto unregister;
 	}
 
 	if (!scanphys)
@@ -255,7 +261,7 @@ 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