ath9k_htc: Maintain individual counters for interfaces

This is required for allowing only one IBSS interface to be
configured.

Signed-off-by: Sujith Manoharan <Sujith.Manoharan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath/ath9k/htc.h

@@ -206,6 +206,32 @@ struct ath9k_htc_target_stats {
 
 #define ATH9K_HTC_MAX_VIF 2
 
+#define INC_VIF(_priv, _type) do {		\
+		switch (_type) {		\
+		case NL80211_IFTYPE_STATION:	\
+			_priv->num_sta_vif++;	\
+			break;			\
+		case NL80211_IFTYPE_ADHOC:	\
+			_priv->num_ibss_vif++;	\
+			break;			\
+		default:			\
+			break;			\
+		}				\
+	} while (0)
+
+#define DEC_VIF(_priv, _type) do {		\
+		switch (_type) {		\
+		case NL80211_IFTYPE_STATION:	\
+			_priv->num_sta_vif--;	\
+			break;			\
+		case NL80211_IFTYPE_ADHOC:	\
+			_priv->num_ibss_vif--;	\
+			break;			\
+		default:			\
+			break;			\
+		}				\
+	} while (0)
+
 struct ath9k_htc_vif {
 	u8 index;
 	u16 seq_no;
@@ -367,6 +393,8 @@ struct ath9k_htc_priv {
 	u8 mon_vif_idx;
 	u8 sta_slot;
 	u8 vif_sta_pos[ATH9K_HTC_MAX_VIF];
+	u8 num_ibss_vif;
+	u8 num_sta_vif;
 
 	u16 op_flags;
 	u16 curtxpow;

drivers/net/wireless/ath/ath9k/htc_drv_main.c

@@ -1193,9 +1193,15 @@ static int ath9k_htc_add_interface(struct ieee80211_hw *hw,
 	mutex_lock(&priv->mutex);
 
 	if (priv->nvifs >= ATH9K_HTC_MAX_VIF) {
-		ret = -ENOBUFS;
 		mutex_unlock(&priv->mutex);
-		return ret;
+		return -ENOBUFS;
+	}
+
+	if (priv->num_ibss_vif ||
+	    (priv->nvifs && vif->type == NL80211_IFTYPE_ADHOC)) {
+		ath_err(common, "IBSS coexistence with other modes is not allowed\n");
+		mutex_unlock(&priv->mutex);
+		return -ENOBUFS;
 	}
 
 	ath9k_htc_ps_wakeup(priv);
@@ -1240,6 +1246,8 @@ static int ath9k_htc_add_interface(struct ieee80211_hw *hw,
 	priv->nvifs++;
 	priv->vif = vif;
 
+	INC_VIF(priv, vif->type);
+
 	ath_dbg(common, ATH_DBG_CONFIG,
 		"Attach a VIF of type: %d at idx: %d\n", vif->type, avp->index);
 
@@ -1273,6 +1281,8 @@ static void ath9k_htc_remove_interface(struct ieee80211_hw *hw,
 	ath9k_htc_remove_station(priv, vif, NULL);
 	priv->vif = NULL;
 
+	DEC_VIF(priv, vif->type);
+
 	ath_dbg(common, ATH_DBG_CONFIG, "Detach Interface at idx: %d\n", avp->index);
 
 	ath9k_htc_ps_restore(priv);