3 files changed, 47 insertions, 60 deletions

diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c
index 7140de475c07..221ebde4318d 100644
--- a/net/dsa/dsa.c
+++ b/net/dsa/dsa.c
@@ -29,6 +29,33 @@
 
 char dsa_driver_version[] = "0.1";
 
+static struct sk_buff *dsa_slave_notag_xmit(struct sk_buff *skb,
+					    struct net_device *dev)
+{
+	/* Just return the original SKB */
+	return skb;
+}
+
+static const struct dsa_device_ops none_ops = {
+	.xmit	= dsa_slave_notag_xmit,
+	.rcv	= NULL,
+};
+
+const struct dsa_device_ops *dsa_device_ops[DSA_TAG_LAST] = {
+#ifdef CONFIG_NET_DSA_TAG_DSA
+	[DSA_TAG_PROTO_DSA] = &dsa_netdev_ops,
+#endif
+#ifdef CONFIG_NET_DSA_TAG_EDSA
+	[DSA_TAG_PROTO_EDSA] = &edsa_netdev_ops,
+#endif
+#ifdef CONFIG_NET_DSA_TAG_TRAILER
+	[DSA_TAG_PROTO_TRAILER] = &trailer_netdev_ops,
+#endif
+#ifdef CONFIG_NET_DSA_TAG_BRCM
+	[DSA_TAG_PROTO_BRCM] = &brcm_netdev_ops,
+#endif
+	[DSA_TAG_PROTO_NONE] = &none_ops,
+};
 
 /* switch driver registration ***********************************************/
 static DEFINE_MUTEX(dsa_switch_drivers_mutex);
@@ -225,6 +252,20 @@ static int dsa_cpu_dsa_setups(struct dsa_switch *ds, struct device *dev)
 	return 0;
 }
 
+const struct dsa_device_ops *dsa_resolve_tag_protocol(int tag_protocol)
+{
+	const struct dsa_device_ops *ops;
+
+	if (tag_protocol >= DSA_TAG_LAST)
+		return ERR_PTR(-EINVAL);
+	ops = dsa_device_ops[tag_protocol];
+
+	if (!ops)
+		return ERR_PTR(-ENOPROTOOPT);
+
+	return ops;
+}
+
 static int dsa_switch_setup_one(struct dsa_switch *ds, struct device *parent)
 {
 	struct dsa_switch_driver *drv = ds->drv;
@@ -277,35 +318,13 @@ static int dsa_switch_setup_one(struct dsa_switch *ds, struct device *parent)
 	 * switch.
 	 */
 	if (dst->cpu_switch == index) {
-		switch (drv->tag_protocol) {
-#ifdef CONFIG_NET_DSA_TAG_DSA
-		case DSA_TAG_PROTO_DSA:
-			dst->rcv = dsa_netdev_ops.rcv;
-			break;
-#endif
-#ifdef CONFIG_NET_DSA_TAG_EDSA
-		case DSA_TAG_PROTO_EDSA:
-			dst->rcv = edsa_netdev_ops.rcv;
-			break;
-#endif
-#ifdef CONFIG_NET_DSA_TAG_TRAILER
-		case DSA_TAG_PROTO_TRAILER:
-			dst->rcv = trailer_netdev_ops.rcv;
-			break;
-#endif
-#ifdef CONFIG_NET_DSA_TAG_BRCM
-		case DSA_TAG_PROTO_BRCM:
-			dst->rcv = brcm_netdev_ops.rcv;
-			break;
-#endif
-		case DSA_TAG_PROTO_NONE:
-			break;
-		default:
-			ret = -ENOPROTOOPT;
+		dst->tag_ops = dsa_resolve_tag_protocol(drv->tag_protocol);
+		if (IS_ERR(dst->tag_ops)) {
+			ret = PTR_ERR(dst->tag_ops);
 			goto out;
 		}
 
-		dst->tag_protocol = drv->tag_protocol;
+		dst->rcv = dst->tag_ops->rcv;
 	}
 
 	memcpy(ds->rtable, cd->rtable, sizeof(ds->rtable));
diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h
index dbea5d9e7f75..72f7b8989cfb 100644
--- a/net/dsa/dsa_priv.h
+++ b/net/dsa/dsa_priv.h
@@ -53,6 +53,7 @@ extern char dsa_driver_version[];
 int dsa_cpu_dsa_setup(struct dsa_switch *ds, struct device *dev,
 		      struct device_node *port_dn, int port);
 void dsa_cpu_dsa_destroy(struct device_node *port_dn);
+const struct dsa_device_ops *dsa_resolve_tag_protocol(int tag_protocol);
 
 /* slave.c */
 extern const struct dsa_device_ops notag_netdev_ops;
diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index 52f1183c42a0..35e5f0f6688b 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -521,14 +521,6 @@ static netdev_tx_t dsa_slave_xmit(struct sk_buff *skb, struct net_device *dev)
 	return NETDEV_TX_OK;
 }
 
-static struct sk_buff *dsa_slave_notag_xmit(struct sk_buff *skb,
-					    struct net_device *dev)
-{
-	/* Just return the original SKB */
-	return skb;
-}
-
-
 /* ethtool operations *******************************************************/
 static int
 dsa_slave_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
@@ -1151,32 +1143,7 @@ int dsa_slave_create(struct dsa_switch *ds, struct device *parent,
 	p = netdev_priv(slave_dev);
 	p->parent = ds;
 	p->port = port;
-
-	switch (ds->dst->tag_protocol) {
-#ifdef CONFIG_NET_DSA_TAG_DSA
-	case DSA_TAG_PROTO_DSA:
-		p->xmit = dsa_netdev_ops.xmit;
-		break;
-#endif
-#ifdef CONFIG_NET_DSA_TAG_EDSA
-	case DSA_TAG_PROTO_EDSA:
-		p->xmit = edsa_netdev_ops.xmit;
-		break;
-#endif
-#ifdef CONFIG_NET_DSA_TAG_TRAILER
-	case DSA_TAG_PROTO_TRAILER:
-		p->xmit = trailer_netdev_ops.xmit;
-		break;
-#endif
-#ifdef CONFIG_NET_DSA_TAG_BRCM
-	case DSA_TAG_PROTO_BRCM:
-		p->xmit = brcm_netdev_ops.xmit;
-		break;
-#endif
-	default:
-		p->xmit	= dsa_slave_notag_xmit;
-		break;
-	}
+	p->xmit = dst->tag_ops->xmit;
 
 	p->old_pause = -1;
 	p->old_link = -1;