net: Move PHY statistics code into PHY library helpers

In order to make it possible for network device drivers that do not
necessarily have a phy_device attached, but still report PHY statistics,
have a preliminary refactoring consisting in creating helper functions
that encapsulate the PHY device driver knowledge within PHYLIB.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/phy/phy.c

@@ -1277,3 +1277,51 @@ int phy_ethtool_nway_reset(struct net_device *ndev)
 	return phy_restart_aneg(phydev);
 }
 EXPORT_SYMBOL(phy_ethtool_nway_reset);
+
+int phy_ethtool_get_strings(struct phy_device *phydev, u8 *data)
+{
+	if (!phydev->drv)
+		return -EIO;
+
+	mutex_lock(&phydev->lock);
+	phydev->drv->get_strings(phydev, data);
+	mutex_unlock(&phydev->lock);
+
+	return 0;
+}
+EXPORT_SYMBOL(phy_ethtool_get_strings);
+
+int phy_ethtool_get_sset_count(struct phy_device *phydev)
+{
+	int ret;
+
+	if (!phydev->drv)
+		return -EIO;
+
+	if (phydev->drv->get_sset_count &&
+	    phydev->drv->get_strings &&
+	    phydev->drv->get_stats) {
+		mutex_lock(&phydev->lock);
+		ret = phydev->drv->get_sset_count(phydev);
+		mutex_unlock(&phydev->lock);
+
+		return ret;
+	}
+
+	return -EOPNOTSUPP;
+}
+EXPORT_SYMBOL(phy_ethtool_get_sset_count);
+
+int phy_ethtool_get_stats(struct phy_device *phydev,
+			  struct ethtool_stats *stats, u64 *data)
+{
+	if (!phydev->drv)
+		return -EIO;
+
+	mutex_lock(&phydev->lock);
+	phydev->drv->get_stats(phydev, stats, data);
+	mutex_unlock(&phydev->lock);
+
+	return 0;
+}
+EXPORT_SYMBOL(phy_ethtool_get_stats);