[PATCH 2/3] net: dsa: lantiq_gswip: fix OF child-node lookups

[Johan Hovold]

Use the new of_get_compatible_child() helper to look up child nodes to
avoid ever matching non-child nodes elsewhere in the tree.

Also fix up the related struct device_node leaks.

Fixes: 14fceff4771e ("net: dsa: Add Lantiq / Intel DSA driver for vrx200")
Cc: stable <sta...@vger.kernel.org>     # 4.20
Cc: Hauke Mehrtens <ha...@hauke-m.de>
Signed-off-by: Johan Hovold <jo...@kernel.org>
---
 drivers/net/dsa/lantiq_gswip.c | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/drivers/net/dsa/lantiq_gswip.c b/drivers/net/dsa/lantiq_gswip.c
index b06c41c98de9..5792674dd4e4 100644
--- a/drivers/net/dsa/lantiq_gswip.c
+++ b/drivers/net/dsa/lantiq_gswip.c
@@ -1069,10 +1069,10 @@ static int gswip_probe(struct platform_device *pdev)
        version = gswip_switch_r(priv, GSWIP_VERSION);
 
        /* bring up the mdio bus */
-       gphy_fw_np = of_find_compatible_node(pdev->dev.of_node, NULL,
-                                            "lantiq,gphy-fw");
+       gphy_fw_np = of_get_compatible_child(dev->of_node, "lantiq,gphy-fw");
        if (gphy_fw_np) {
                err = gswip_gphy_fw_list(priv, gphy_fw_np, version);
+               of_node_put(gphy_fw_np);
                if (err) {
                        dev_err(dev, "gphy fw probe failed\n");
                        return err;
@@ -1080,13 +1080,12 @@ static int gswip_probe(struct platform_device *pdev)
        }
 
        /* bring up the mdio bus */
-       mdio_np = of_find_compatible_node(pdev->dev.of_node, NULL,
-                                         "lantiq,xrx200-mdio");
+       mdio_np = of_get_compatible_child(dev->of_node, "lantiq,xrx200-mdio");
        if (mdio_np) {
                err = gswip_mdio(priv, mdio_np);
                if (err) {
                        dev_err(dev, "mdio probe failed\n");
-                       goto gphy_fw;
+                       goto put_mdio_node;
                }
        }
 
@@ -1115,7 +1114,8 @@ static int gswip_probe(struct platform_device *pdev)
 mdio_bus:
        if (mdio_np)
                mdiobus_unregister(priv->ds->slave_mii_bus);
-gphy_fw:
+put_mdio_node:
+       of_node_put(mdio_np);
        for (i = 0; i < priv->num_gphy_fw; i++)
                gswip_gphy_fw_remove(priv, &priv->gphy_fw[i]);
        return err;
@@ -1134,8 +1134,10 @@ static int gswip_remove(struct platform_device *pdev)
 
        dsa_unregister_switch(priv->ds);
 
-       if (priv->ds->slave_mii_bus)
+       if (priv->ds->slave_mii_bus) {
                mdiobus_unregister(priv->ds->slave_mii_bus);
+               of_node_put(priv->ds->slave_mii_bus->dev.of_node);
+       }
 
        for (i = 0; i < priv->num_gphy_fw; i++)
                gswip_gphy_fw_remove(priv, &priv->gphy_fw[i]);
-- 
2.20.1