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>
diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
index 380b042..9b660bd 100644
--- a/include/linux/ethtool.h
+++ b/include/linux/ethtool.h
@@ -30,7 +30,8 @@
 	__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 @@
 #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)