+/* Read AN Link Status */
+static int is_an_link_up(struct phy_device *bpphy)
+{
+	struct backplane_phy_info *bp_phy = bpphy->priv;
+	int ret, val = 0;
+
+	mutex_lock(&bp_phy->bpphy_lock);
+
+	/* Read twice because Link_Status is LL (Latched Low) bit */
+	val = phy_read_mmd(bpphy, MDIO_MMD_AN, bp_phy->bp_dev.mdio.an_status);
+	val = phy_read_mmd(bpphy, MDIO_MMD_AN, bp_phy->bp_dev.mdio.an_status);
+
+	mutex_unlock(&bp_phy->bpphy_lock);

How does this mutex interact with phydev->lock? It appears both are
trying to do the same thing, serialise access to the PHY hardware.

	 Andrew