net: dsa: Add more convenient functions for installing port VLANs

This hides the need to perform a two-phase transaction and construct a
switchdev_obj_port_vlan struct.

Call graph (including a function that will be introduced in a follow-up
patch) looks like this now (same for the *_vlan_del function):

dsa_slave_vlan_rx_add_vid   dsa_port_setup_8021q_tagging
            |                        |
            |                        |
            |          +-------------+
            |          |
            v          v
           dsa_port_vid_add      dsa_slave_port_obj_add
                  |                         |
                  +-------+         +-------+
                          |         |
                          v         v
                       dsa_port_vlan_add

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/dsa/dsa_priv.h

@@ -171,6 +171,8 @@ int dsa_port_vlan_add(struct dsa_port *dp,
 		      struct switchdev_trans *trans);
 int dsa_port_vlan_del(struct dsa_port *dp,
 		      const struct switchdev_obj_port_vlan *vlan);
+int dsa_port_vid_add(struct dsa_port *dp, u16 vid, u16 flags);
+int dsa_port_vid_del(struct dsa_port *dp, u16 vid);
 int dsa_port_link_register_of(struct dsa_port *dp);
 void dsa_port_link_unregister_of(struct dsa_port *dp);
 

net/dsa/port.c

@@ -370,6 +370,37 @@ int dsa_port_vlan_del(struct dsa_port *dp,
 	return 0;
 }
 
+int dsa_port_vid_add(struct dsa_port *dp, u16 vid, u16 flags)
+{
+	struct switchdev_obj_port_vlan vlan = {
+		.obj.id = SWITCHDEV_OBJ_ID_PORT_VLAN,
+		.flags = flags,
+		.vid_begin = vid,
+		.vid_end = vid,
+	};
+	struct switchdev_trans trans;
+	int err;
+
+	trans.ph_prepare = true;
+	err = dsa_port_vlan_add(dp, &vlan, &trans);
+	if (err == -EOPNOTSUPP)
+		return 0;
+
+	trans.ph_prepare = false;
+	return dsa_port_vlan_add(dp, &vlan, &trans);
+}
+
+int dsa_port_vid_del(struct dsa_port *dp, u16 vid)
+{
+	struct switchdev_obj_port_vlan vlan = {
+		.obj.id = SWITCHDEV_OBJ_ID_PORT_VLAN,
+		.vid_begin = vid,
+		.vid_end = vid,
+	};
+
+	return dsa_port_vlan_del(dp, &vlan);
+}
+
 static struct phy_device *dsa_port_get_phy_device(struct dsa_port *dp)
 {
 	struct device_node *phy_dn;

net/dsa/slave.c

@@ -1001,13 +1001,6 @@ static int dsa_slave_vlan_rx_add_vid(struct net_device *dev, __be16 proto,
 				     u16 vid)
 {
 	struct dsa_port *dp = dsa_slave_to_port(dev);
-	struct switchdev_obj_port_vlan vlan = {
-		.vid_begin = vid,
-		.vid_end = vid,
-		/* This API only allows programming tagged, non-PVID VIDs */
-		.flags = 0,
-	};
-	struct switchdev_trans trans;
 	struct bridge_vlan_info info;
 	int ret;
 
@@ -1024,25 +1017,14 @@ static int dsa_slave_vlan_rx_add_vid(struct net_device *dev, __be16 proto,
 			return -EBUSY;
 	}
 
-	trans.ph_prepare = true;
-	ret = dsa_port_vlan_add(dp, &vlan, &trans);
-	if (ret == -EOPNOTSUPP)
-		return 0;
-
-	trans.ph_prepare = false;
-	return dsa_port_vlan_add(dp, &vlan, &trans);
+	/* This API only allows programming tagged, non-PVID VIDs */
+	return dsa_port_vid_add(dp, vid, 0);
 }
 
 static int dsa_slave_vlan_rx_kill_vid(struct net_device *dev, __be16 proto,
 				      u16 vid)
 {
 	struct dsa_port *dp = dsa_slave_to_port(dev);
-	struct switchdev_obj_port_vlan vlan = {
-		.vid_begin = vid,
-		.vid_end = vid,
-		/* This API only allows programming tagged, non-PVID VIDs */
-		.flags = 0,
-	};
 	struct bridge_vlan_info info;
 	int ret;
 
@@ -1059,7 +1041,7 @@ static int dsa_slave_vlan_rx_kill_vid(struct net_device *dev, __be16 proto,
 			return -EBUSY;
 	}
 
-	ret = dsa_port_vlan_del(dp, &vlan);
+	ret = dsa_port_vid_del(dp, vid);
 	if (ret == -EOPNOTSUPP)
 		ret = 0;