wpa_supplicant: Fall back to avg_signal in roaming decision

Some drivers (e.g. Marvell WiFi) don't report avg_beacon_signal, but
it's still useful to poll for the signal again when a roaming decision
needs to be made. Use si.avg_signal when si.avg_beacon_signal is not
available.

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

diff --git a/wpa_supplicant/events.c b/wpa_supplicant/events.c
index 6b7cf7c6fe7a83e0a3ab379c67c6aed5d186e6cb..cc6cb6716bbe0541a3ab44881764e99be4cb1f42 100644 (file)
--- a/wpa_supplicant/events.c
+++ b/wpa_supplicant/events.c
@@ -1672,9 +1672,9 @@ static void wpa_supplicant_rsn_preauth_scan_results(
 }
 
 
-static int wpas_get_snr_signal_info(const struct wpa_signal_info *si)
+static int wpas_get_snr_signal_info(u32 frequency, int avg_signal)
 {
-       int noise = IS_5GHZ(si->frequency) ?
+       int noise = IS_5GHZ(frequency) ?
                DEFAULT_NOISE_FLOOR_5GHZ :
                DEFAULT_NOISE_FLOOR_2GHZ;
 
@@ -1683,7 +1683,7 @@ static int wpas_get_snr_signal_info(const struct wpa_signal_info *si)
         * the current noise measurement (average vs. snapshot),
         * so use the default values instead.
         */
-       return si->avg_beacon_signal - noise;
+       return avg_signal - noise;
 }
 
 
@@ -1779,10 +1779,13 @@ static int wpa_supplicant_need_to_roam(struct wpa_supplicant *wpa_s,
         * information about our currently associated AP.
         */
        if (wpa_drv_signal_poll(wpa_s, &si) == 0 &&
-           si.avg_beacon_signal) {
-               int snr = wpas_get_snr_signal_info(&si);
+           (si.avg_beacon_signal || si.avg_signal)) {
+               int snr;
+
+               cur_level = si.avg_beacon_signal ? si.avg_beacon_signal :
+                       si.avg_signal;
+               snr = wpas_get_snr_signal_info(si.frequency, cur_level);
 
-               cur_level = si.avg_beacon_signal;
                cur_est = wpas_get_est_throughput_from_bss_snr(wpa_s,
                                                               current_bss,
                                                               snr);