mt76: mt76x02u: enable multi-vif support

Enable multi-interface support for mt76x02u driver. For the moment
allow max two concurrent interfaces in order to preserve enough room
for ps traffic since we are using beacon slots for it.
I have successfully tested the following configuration:
- AP + STA
- AP0 + AP1
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Tested-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

drivers/net/wireless/mediatek/mt76/mt76x02_util.c

@@ -50,6 +50,20 @@ static const struct ieee80211_iface_limit mt76x02_if_limits[] = {
 	 },
 };
 
+static const struct ieee80211_iface_limit mt76x02u_if_limits[] = {
+	{
+		.max = 1,
+		.types = BIT(NL80211_IFTYPE_ADHOC)
+	}, {
+		.max = 2,
+		.types = BIT(NL80211_IFTYPE_STATION) |
+#ifdef CONFIG_MAC80211_MESH
+			 BIT(NL80211_IFTYPE_MESH_POINT) |
+#endif
+			 BIT(NL80211_IFTYPE_AP)
+	},
+};
+
 static const struct ieee80211_iface_combination mt76x02_if_comb[] = {
 	{
 		.limits = mt76x02_if_limits,
@@ -64,6 +78,16 @@ static const struct ieee80211_iface_combination mt76x02_if_comb[] = {
 	}
 };
 
+static const struct ieee80211_iface_combination mt76x02u_if_comb[] = {
+	{
+		.limits = mt76x02u_if_limits,
+		.n_limits = ARRAY_SIZE(mt76x02u_if_limits),
+		.max_interfaces = 2,
+		.num_different_channels = 1,
+		.beacon_int_infra_match = true,
+	}
+};
+
 static void
 mt76x02_led_set_config(struct mt76_dev *mdev, u8 delay_on,
 		       u8 delay_off)
@@ -140,6 +164,8 @@ void mt76x02_init_device(struct mt76x02_dev *dev)
 	if (mt76_is_usb(dev)) {
 		hw->extra_tx_headroom += sizeof(struct mt76x02_txwi) +
 					 MT_DMA_HDR_LEN;
+		wiphy->iface_combinations = mt76x02u_if_comb;
+		wiphy->n_iface_combinations = ARRAY_SIZE(mt76x02u_if_comb);
 	} else {
 		INIT_DELAYED_WORK(&dev->wdt_work, mt76x02_wdt_work);