P2P: Allow driver wrapper to indicate how many stations are supported

This can be used to limit the number of clients allowed to connect
to the group on the GO.

src/drivers/driver.h

@@ -550,6 +550,12 @@ struct wpa_driver_capa {
 	 * max_remain_on_chan - Maximum remain-on-channel duration in msec
 	 */
 	unsigned int max_remain_on_chan;
+
+	/**
+	 * max_stations - Maximum number of associated stations the driver
+	 * supports in AP mode
+	 */
+	unsigned int max_stations;
 };
 
 

wpa_supplicant/p2p_supplicant.c

@@ -2160,7 +2160,7 @@ int wpas_p2p_init(struct wpa_global *global, struct wpa_supplicant *wpa_s)
 	p2p.concurrent_operations = !!(wpa_s->drv_flags &
 				       WPA_DRIVER_FLAGS_P2P_CONCURRENT);
 
-	p2p.max_peers = 100;
+	p2p.max_peers = wpa_s->max_stations ? wpa_s->max_stations : 100;
 
 	if (wpa_s->conf->p2p_ssid_postfix) {
 		p2p.ssid_postfix_len =

wpa_supplicant/wpa_supplicant.c

@@ -2101,6 +2101,7 @@ next_driver:
 		}
 		wpa_s->max_scan_ssids = capa.max_scan_ssids;
 		wpa_s->max_remain_on_chan = capa.max_remain_on_chan;
+		wpa_s->max_stations = capa.max_stations;
 	}
 	if (wpa_s->max_remain_on_chan == 0)
 		wpa_s->max_remain_on_chan = 1000;

wpa_supplicant/wpa_supplicant_i.h

@@ -408,6 +408,7 @@ struct wpa_supplicant {
 	unsigned int drv_flags;
 	int max_scan_ssids;
 	unsigned int max_remain_on_chan;
+	unsigned int max_stations;
 
 	int pending_mic_error_report;
 	int pending_mic_error_pairwise;