net: phy: fix phy_validate_pause

[ Upstream commit b4010af9 ]

We have valid scenarios where ETHTOOL_LINK_MODE_Pause_BIT doesn't
need to be supported. Therefore extend the first check to check
for rx_pause being set.

See also phy_set_asym_pause:
rx=0 and tx=1: advertise asym pause only
rx=0 and tx=0: stop advertising both pause modes

The fixed commit isn't wrong, it's just the one that introduced the
linkmode bitmaps.

Fixes: 3c1bcc86 ("net: ethernet: Convert phydev advertize and supported from u32 to link mode")
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/net/phy/phy_device.c

@@ -2044,11 +2044,14 @@ bool phy_validate_pause(struct phy_device *phydev,
 			struct ethtool_pauseparam *pp)
 {
 	if (!linkmode_test_bit(ETHTOOL_LINK_MODE_Pause_BIT,
-			       phydev->supported) ||
-	    (!linkmode_test_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT,
-				phydev->supported) &&
-	     pp->rx_pause != pp->tx_pause))
+			       phydev->supported) && pp->rx_pause)
 		return false;
+
+	if (!linkmode_test_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT,
+			       phydev->supported) &&
+	    pp->rx_pause != pp->tx_pause)
+		return false;
+
 	return true;
 }
 EXPORT_SYMBOL(phy_validate_pause);