r8169: keep pause settings on interface down/up cycle

Currently, if the user changes the pause settings, the default settings
will be restored after an interface down/up cycle, and also when
resuming from suspend. This doesn't seem to provide the best user
experience. Change this to keep user settings, and just ensure that in
jumbo mode pause is disabled.
Small drawback: When switching back mtu from jumbo to non-jumbo then
pause remains disabled (but user can enable it using ethtool).
I think that's a not too common scenario and acceptable.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/realtek/r8169_main.c

@@ -2388,11 +2388,13 @@ static void rtl_jumbo_config(struct rtl8169_private *tp)
 		pcie_set_readrq(tp->pci_dev, readrq);
 
 	/* Chip doesn't support pause in jumbo mode */
-	linkmode_mod_bit(ETHTOOL_LINK_MODE_Pause_BIT,
-			 tp->phydev->advertising, !jumbo);
-	linkmode_mod_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT,
-			 tp->phydev->advertising, !jumbo);
-	phy_start_aneg(tp->phydev);
+	if (jumbo) {
+		linkmode_clear_bit(ETHTOOL_LINK_MODE_Pause_BIT,
+				   tp->phydev->advertising);
+		linkmode_clear_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT,
+				   tp->phydev->advertising);
+		phy_start_aneg(tp->phydev);
+	}
 }
 
 DECLARE_RTL_COND(rtl_chipcmd_cond)
@@ -5121,6 +5123,8 @@ static int r8169_mdio_register(struct rtl8169_private *tp)
 
 	tp->phydev->mac_managed_pm = 1;
 
+	phy_support_asym_pause(tp->phydev);
+
 	/* PHY will be woken up in rtl_open() */
 	phy_suspend(tp->phydev);