net: eth: Add helper to return VLAN info for an interface

A small helper function will return information whether
a given network interface has VLAN enabled or not.

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>

include/net/ethernet.h

@@ -369,6 +369,15 @@ struct net_if *net_eth_get_vlan_iface(struct net_if *iface, u16_t tag);
 bool net_eth_is_vlan_enabled(struct ethernet_context *ctx,
 			     struct net_if *iface);
 
+/**
+ * @brief Get VLAN status for a given network interface (enabled or not).
+ *
+ * @param iface Network interface
+ *
+ * @return True if VLAN is enabled for this network interface, false if not.
+ */
+bool net_eth_get_vlan_status(struct net_if *iface);
+
 #define ETH_NET_DEVICE_INIT(dev_name, drv_name, init_fn,		 \
 			    data, cfg_info, prio, api, mtu)		 \
 	DEVICE_AND_API_INIT(dev_name, drv_name, init_fn, data,		 \
@@ -404,6 +413,11 @@ struct net_if *net_eth_get_vlan_iface(struct net_if *iface, u16_t tag)
 {
 	return NULL;
 }
+
+static inline bool net_eth_get_vlan_status(struct net_if *iface)
+{
+	return false;
+}
 #endif /* CONFIG_NET_VLAN */
 
 /**

subsys/net/l2/ethernet/ethernet.c

@@ -651,6 +651,18 @@ u16_t net_eth_get_vlan_tag(struct net_if *iface)
 	return NET_VLAN_TAG_UNSPEC;
 }
 
+bool net_eth_get_vlan_status(struct net_if *iface)
+{
+	struct ethernet_context *ctx = net_if_l2_data(iface);
+
+	if (ctx->vlan_enabled &&
+	    net_eth_get_vlan_tag(iface) != NET_VLAN_TAG_UNSPEC) {
+		return true;
+	}
+
+	return false;
+}
+
 static struct ethernet_vlan *get_vlan(struct ethernet_context *ctx,
 				      struct net_if *iface,
 				      u16_t vlan_tag)