net: phy: ensure that genphy_c45_an_config_eee_aneg() sees new value of phydev->eee_cfg.eee_enabled

This is a follow-up to 41ffcd9 ("net: phy: fix phylib's dual
eee_enabled") and resolves an issue with genphy_c45_an_config_eee_aneg()
(called from genphy_c45_ethtool_set_eee) not seeing the new value of
phydev->eee_cfg.eee_enabled.

Fixes: 49168d1 ("net: phy: Add phy_support_eee() indicating MAC support EEE")
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reported-by: Choong Yong Liang <yong.liang.choong@linux.intel.com>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit f26a29a)

Author: hkallweit

drivers/net/phy/phy.c

@@ -1728,7 +1728,7 @@ EXPORT_SYMBOL(phy_ethtool_get_eee);
  * phy_ethtool_set_eee_noneg - Adjusts MAC LPI configuration without PHY
  *			       renegotiation
  * @phydev: pointer to the target PHY device structure
- * @data: pointer to the ethtool_keee structure containing the new EEE settings
+ * @old_cfg: pointer to the eee_config structure containing the old EEE settings
  *
  * This function updates the Energy Efficient Ethernet (EEE) configuration
  * for cases where only the MAC's Low Power Idle (LPI) configuration changes,
@@ -1739,11 +1739,10 @@ EXPORT_SYMBOL(phy_ethtool_get_eee);
  * configuration.
  */
 static void phy_ethtool_set_eee_noneg(struct phy_device *phydev,
-				      struct ethtool_keee *data)
+				      const struct eee_config *old_cfg)
 {
-	if (phydev->eee_cfg.tx_lpi_enabled != data->tx_lpi_enabled ||
-	    phydev->eee_cfg.tx_lpi_timer != data->tx_lpi_timer) {
-		eee_to_eeecfg(&phydev->eee_cfg, data);
+	if (phydev->eee_cfg.tx_lpi_enabled != old_cfg->tx_lpi_enabled ||
+	    phydev->eee_cfg.tx_lpi_timer != old_cfg->tx_lpi_timer) {
 		phydev->enable_tx_lpi = eeecfg_mac_can_tx_lpi(&phydev->eee_cfg);
 		if (phydev->link) {
 			phydev->link = false;
@@ -1763,18 +1762,23 @@ static void phy_ethtool_set_eee_noneg(struct phy_device *phydev,
  */
 int phy_ethtool_set_eee(struct phy_device *phydev, struct ethtool_keee *data)
 {
+	struct eee_config old_cfg;
 	int ret;
 
 	if (!phydev->drv)
 		return -EIO;
 
 	mutex_lock(&phydev->lock);
+
+	old_cfg = phydev->eee_cfg;
+	eee_to_eeecfg(&phydev->eee_cfg, data);
+
 	ret = genphy_c45_ethtool_set_eee(phydev, data);
-	if (ret >= 0) {
-		if (ret == 0)
-			phy_ethtool_set_eee_noneg(phydev, data);
-		eee_to_eeecfg(&phydev->eee_cfg, data);
-	}
+	if (ret == 0)
+		phy_ethtool_set_eee_noneg(phydev, &old_cfg);
+	else if (ret < 0)
+		phydev->eee_cfg = old_cfg;
+
 	mutex_unlock(&phydev->lock);
 
 	return ret < 0 ? ret : 0;