ixgbe: add new bridge mode support function.

This patch gathers together all the logic needed to configure bridge
modes.  Currently that it is rather simple but this is really laying
the ground work for future X550 feature enhancement.

Signed-off-by: Don Skidmore <donald.c.skidmore@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/ixgbe/ixgbe_main.c

@@ -7870,6 +7870,36 @@ static int ixgbe_ndo_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
 	return ndo_dflt_fdb_add(ndm, tb, dev, addr, vid, flags);
 }
 
+/**
+ * ixgbe_configure_bridge_mode - set various bridge modes
+ * @adapter - the private structure
+ * @mode - requested bridge mode
+ *
+ * Configure some settings require for various bridge modes.
+ **/
+static int ixgbe_configure_bridge_mode(struct ixgbe_adapter *adapter,
+				       __u16 mode)
+{
+	switch (mode) {
+	case BRIDGE_MODE_VEPA:
+		IXGBE_WRITE_REG(&adapter->hw, IXGBE_PFDTXGSWC, 0);
+		break;
+	case BRIDGE_MODE_VEB:
+		IXGBE_WRITE_REG(&adapter->hw, IXGBE_PFDTXGSWC,
+				IXGBE_PFDTXGSWC_VT_LBEN);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	adapter->bridge_mode = mode;
+
+	e_info(drv, "enabling bridge mode: %s\n",
+	       mode == BRIDGE_MODE_VEPA ? "VEPA" : "VEB");
+
+	return 0;
+}
+
 static int ixgbe_ndo_bridge_setlink(struct net_device *dev,
 				    struct nlmsghdr *nlh, u16 flags)
 {
@@ -7885,6 +7915,7 @@ static int ixgbe_ndo_bridge_setlink(struct net_device *dev,
 		return -EINVAL;
 
 	nla_for_each_nested(attr, br_spec, rem) {
+		u32 status;
 		__u16 mode;
 
 		if (nla_type(attr) != IFLA_BRIDGE_MODE)
@@ -7894,22 +7925,9 @@ static int ixgbe_ndo_bridge_setlink(struct net_device *dev,
 			return -EINVAL;
 
 		mode = nla_get_u16(attr);
-		switch (mode) {
-		case BRIDGE_MODE_VEPA:
-			IXGBE_WRITE_REG(&adapter->hw, IXGBE_PFDTXGSWC, 0);
-			break;
-		case BRIDGE_MODE_VEB:
-			IXGBE_WRITE_REG(&adapter->hw, IXGBE_PFDTXGSWC,
-					IXGBE_PFDTXGSWC_VT_LBEN);
-			break;
-		default:
-			return -EINVAL;
-		}
-
-		adapter->bridge_mode = mode;
-
-		e_info(drv, "enabling bridge mode: %s\n",
-			mode == BRIDGE_MODE_VEPA ? "VEPA" : "VEB");
+		status = ixgbe_configure_bridge_mode(adapter, mode);
+		if (status)
+			return status;
 
 		break;
 	}