e1000e: Expose MDI-X status via ethtool change

Ethtool is a standard way of getting information about
ethernet interfaces.  We enhance ethtool kernel interface
& e1000e to make the MDI-X status readable via ethtool in
userspace.
Signed-off-by: Chaitanya Lala <clala@riverbed.com>
Signed-off-by: Arthur Jones <ajones@riverbed.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/e1000e/ethtool.c

@@ -167,6 +167,15 @@ static int e1000_get_settings(struct net_device *netdev,
 
 	ecmd->autoneg = ((hw->phy.media_type == e1000_media_type_fiber) ||
 			 hw->mac.autoneg) ? AUTONEG_ENABLE : AUTONEG_DISABLE;
+
+	/* MDI-X => 2; MDI =>1; Invalid =>0 */
+	if ((hw->phy.media_type == e1000_media_type_copper) &&
+	    !hw->mac.get_link_status)
+		ecmd->eth_tp_mdix = hw->phy.is_mdix ? ETH_TP_MDI_X :
+		                                      ETH_TP_MDI;
+	else
+		ecmd->eth_tp_mdix = ETH_TP_MDI_INVALID;
+
 	return 0;
 }
 

include/linux/ethtool.h

@@ -30,7 +30,8 @@ struct ethtool_cmd {
 	__u32	maxtxpkt;	/* Tx pkts before generating tx int */
 	__u32	maxrxpkt;	/* Rx pkts before generating rx int */
 	__u16	speed_hi;
-	__u16	reserved2;
+	__u8	eth_tp_mdix;
+	__u8	reserved2;
 	__u32	lp_advertising;	/* Features the link partner advertises */
 	__u32	reserved[2];
 };
@@ -632,6 +633,11 @@ struct ethtool_ops {
 #define AUTONEG_DISABLE		0x00
 #define AUTONEG_ENABLE		0x01
 
+/* Mode MDI or MDI-X */
+#define ETH_TP_MDI_INVALID	0x00
+#define ETH_TP_MDI		0x01
+#define ETH_TP_MDI_X		0x02
+
 /* Wake-On-Lan options. */
 #define WAKE_PHY		(1 << 0)
 #define WAKE_UCAST		(1 << 1)