From: Russell King <rmk+kernel@armlinux.org.uk>
Date: Fri, 29 Dec 2017 12:46:43 +0000
Subject: net: phy: marvell10g: add support for half duplex 100M and 10M
Patch-mainline: v4.16-rc1
Git-commit: 6798d03cfa5ed2f20a4cf33da1d31eba80b4714f
References: bsc#1119113 FATE#326472

Add support for half-duplex 100M and 10M copper connections by parsing
the advertisment results rather than trying to decode the negotiated
speed from one of the PHYs "vendor" registers.  This allows us to
decode the duplex as well, which means we can support half-duplex mode
for the slower speeds.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/phy/marvell10g.c |   37 ++++++++++++-------------------------
 1 file changed, 12 insertions(+), 25 deletions(-)

--- a/drivers/net/phy/marvell10g.c
+++ b/drivers/net/phy/marvell10g.c
@@ -40,13 +40,6 @@ enum {
 	 */
 	MV_AN_CTRL1000		= 0x8000, /* 1000base-T control register */
 	MV_AN_STAT1000		= 0x8001, /* 1000base-T status register */
-
-	/* This register appears to reflect the copper status */
-	MV_AN_RESULT		= 0xa016,
-	MV_AN_RESULT_SPD_10	= BIT(12),
-	MV_AN_RESULT_SPD_100	= BIT(13),
-	MV_AN_RESULT_SPD_1000	= BIT(14),
-	MV_AN_RESULT_SPD_10000	= BIT(15),
 };
 
 static int mv3310_modify(struct phy_device *phydev, int devad, u16 reg,
@@ -160,12 +153,18 @@ static int mv3310_config_init(struct phy
 		if (val & MDIO_PMA_EXTABLE_1000BKX)
 			__set_bit(ETHTOOL_LINK_MODE_1000baseKX_Full_BIT,
 				  supported);
-		if (val & MDIO_PMA_EXTABLE_100BTX)
+		if (val & MDIO_PMA_EXTABLE_100BTX) {
 			__set_bit(ETHTOOL_LINK_MODE_100baseT_Full_BIT,
 				  supported);
-		if (val & MDIO_PMA_EXTABLE_10BT)
+			__set_bit(ETHTOOL_LINK_MODE_100baseT_Half_BIT,
+				  supported);
+		}
+		if (val & MDIO_PMA_EXTABLE_10BT) {
 			__set_bit(ETHTOOL_LINK_MODE_10baseT_Full_BIT,
 				  supported);
+			__set_bit(ETHTOOL_LINK_MODE_10baseT_Half_BIT,
+				  supported);
+		}
 	}
 
 	if (!ethtool_convert_link_mode_to_legacy_u32(&mask, supported))
@@ -325,22 +324,8 @@ static int mv3310_read_status(struct phy
 
 		phydev->lp_advertising |= mii_stat1000_to_ethtool_lpa_t(val);
 
-		if (phydev->autoneg == AUTONEG_ENABLE) {
-			val = phy_read_mmd(phydev, MDIO_MMD_AN, MV_AN_RESULT);
-			if (val < 0)
-				return val;
-
-			if (val & MV_AN_RESULT_SPD_10000)
-				phydev->speed = SPEED_10000;
-			else if (val & MV_AN_RESULT_SPD_1000)
-				phydev->speed = SPEED_1000;
-			else if (val & MV_AN_RESULT_SPD_100)
-				phydev->speed = SPEED_100;
-			else if (val & MV_AN_RESULT_SPD_10)
-				phydev->speed = SPEED_10;
-
-			phydev->duplex = DUPLEX_FULL;
-		}
+		if (phydev->autoneg == AUTONEG_ENABLE)
+			phy_resolve_aneg_linkmode(phydev);
 	}
 
 	if (phydev->autoneg != AUTONEG_ENABLE) {
@@ -382,7 +367,9 @@ static struct phy_driver mv3310_drivers[
 		.phy_id_mask	= MARVELL_PHY_ID_MASK,
 		.name		= "mv88x3310",
 		.features	= SUPPORTED_10baseT_Full |
+				  SUPPORTED_10baseT_Half |
 				  SUPPORTED_100baseT_Full |
+				  SUPPORTED_100baseT_Half |
 				  SUPPORTED_1000baseT_Full |
 				  SUPPORTED_Autoneg |
 				  SUPPORTED_TP |