net: ethernet: ti: davinci_emac: fix device reference leak

Make sure to drop the references taken by bus_find_device() before
returning from emac_dev_open().

Note that phy_connect still takes a reference to the phy device.

Fixes: 5d69e0076a72 ("net: davinci_emac: switch to new mdio")
Cc: Mugunthan V N <mugunthanvnm@ti.com>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: linux-omap@vger.kernel.org
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/ti/davinci_emac.c b/drivers/net/ethernet/ti/davinci_emac.c
index 2fd94a5bc1f3a653bebff3c5b71642fe49b97c24..84fbe5714f8b50edd3902223b02cc42511b20244 100644 (file)
--- a/drivers/net/ethernet/ti/davinci_emac.c
+++ b/drivers/net/ethernet/ti/davinci_emac.c
@@ -1410,6 +1410,7 @@ static int emac_dev_open(struct net_device *ndev)
        int i = 0;
        struct emac_priv *priv = netdev_priv(ndev);
        struct phy_device *phydev = NULL;
+       struct device *phy = NULL;
 
        ret = pm_runtime_get_sync(&priv->pdev->dev);
        if (ret < 0) {
@@ -1488,19 +1489,20 @@ static int emac_dev_open(struct net_device *ndev)
 
        /* use the first phy on the bus if pdata did not give us a phy id */
        if (!phydev && !priv->phy_id) {
-               struct device *phy;
-
                phy = bus_find_device(&mdio_bus_type, NULL, NULL,
                                      match_first_device);
-               if (phy)
+               if (phy) {
                        priv->phy_id = dev_name(phy);
+                       if (!priv->phy_id || !*priv->phy_id)
+                               put_device(phy);
+               }
        }
 
        if (!phydev && priv->phy_id && *priv->phy_id) {
                phydev = phy_connect(ndev, priv->phy_id,
                                     &emac_adjust_link,
                                     PHY_INTERFACE_MODE_MII);
-
+               put_device(phy);        /* reference taken by bus_find_device */
                if (IS_ERR(phydev)) {
                        dev_err(emac_dev, "could not connect to phy %s\n",
                                priv->phy_id);