P2P: Get cached scan results on iface creation to avoid scan

This allows the P2P client to fast associate if the GO is already in the
scan cache without doing a full scan.

Signed-off-by: Matthew Wang <matthewmwang@chromium.org>

diff --git a/wpa_supplicant/p2p_supplicant.c b/wpa_supplicant/p2p_supplicant.c
index 3971eb13434818fb5369c3a718ab87e2e9465812..46199ad703e290102b188c6ea11f48bad675d2d2 100644 (file)
--- a/wpa_supplicant/p2p_supplicant.c
+++ b/wpa_supplicant/p2p_supplicant.c
@@ -6875,6 +6875,8 @@ static int wpas_start_p2p_client(struct wpa_supplicant *wpa_s,
                                 int freq, int force_scan)
 {
        struct wpa_ssid *ssid;
+       int other_iface_found = 0;
+       struct wpa_supplicant *ifs;
 
        wpa_s = wpas_p2p_get_group_iface(wpa_s, addr_allocated, 0);
        if (wpa_s == NULL)
@@ -6919,6 +6921,26 @@ static int wpas_start_p2p_client(struct wpa_supplicant *wpa_s,
        wpa_s->p2p_go_group_formation_completed = 0;
        wpa_s->global->p2p_group_formation = wpa_s;
 
+       /*
+        * Get latest scan results from driver in case cached scan results from
+        * interfaces on the same wiphy allow us to skip the next scan by fast
+        * associating. Also update the scan time to the most recent scan result
+        * fetch time on the same radio so it reflects the actual time the last
+        * scan result event occurred.
+        */
+       wpa_supplicant_update_scan_results(wpa_s);
+       dl_list_for_each(ifs, &wpa_s->radio->ifaces, struct wpa_supplicant,
+                        radio_list) {
+               if (ifs == wpa_s)
+                       continue;
+               if (!other_iface_found || os_reltime_before(&wpa_s->last_scan,
+                                                           &ifs->last_scan)) {
+                       other_iface_found = 1;
+                       wpa_s->last_scan.sec = ifs->last_scan.sec;
+                       wpa_s->last_scan.usec = ifs->last_scan.usec;
+               }
+       }
+
        eloop_cancel_timeout(wpas_p2p_group_formation_timeout, wpa_s->p2pdev,
                             NULL);
        eloop_register_timeout(P2P_MAX_INITIAL_CONN_WAIT, 0,