2 files changed, 23 insertions, 6 deletions

diff --git a/drivers/net/wireless/ipw2x00/ipw2200.c b/drivers/net/wireless/ipw2x00/ipw2200.c
index 23728eb6110a..625f2cf99fa9 100644
--- a/drivers/net/wireless/ipw2x00/ipw2200.c
+++ b/drivers/net/wireless/ipw2x00/ipw2200.c
@@ -4345,7 +4345,8 @@ static void ipw_handle_missed_beacon(struct ipw_priv *priv,
                 return;
         }
 
-        if (priv->status & STATUS_SCANNING) {
+        if (priv->status & STATUS_SCANNING &&
+            missed_count > IPW_MB_SCAN_CANCEL_THRESHOLD) {
                 /* Stop scan to keep fw from getting
                  * stuck (only if we aren't roaming --
                  * otherwise we'll never scan more than 2 or 3
@@ -6271,6 +6272,20 @@ static void ipw_add_scan_channels(struct ipw_priv *priv,
         }
 }
 
+static int ipw_passive_dwell_time(struct ipw_priv *priv)
+{
+        /* staying on passive channels longer than the DTIM interval during a
+         * scan, while associated, causes the firmware to cancel the scan
+         * without notification. Hence, don't stay on passive channels longer
+         * than the beacon interval.
+         */
+        if (priv->status & STATUS_ASSOCIATED
+            && priv->assoc_network->beacon_interval > 10)
+                return priv->assoc_network->beacon_interval - 10;
+        else
+                return 120;
+}
+
 static int ipw_request_scan_helper(struct ipw_priv *priv, int type, int direct)
 {
         struct ipw_scan_request_ext scan;
@@ -6314,16 +6329,16 @@ static int ipw_request_scan_helper(struct ipw_priv *priv, int type, int direct)
         scan.full_scan_index = cpu_to_le32(ieee80211_get_scans(priv->ieee));
 
         if (type == IW_SCAN_TYPE_PASSIVE) {
-                IPW_DEBUG_WX("use passive scanning\n");
-                scan_type = IPW_SCAN_PASSIVE_FULL_DWELL_SCAN;
+                IPW_DEBUG_WX("use passive scanning\n");
+                scan_type = IPW_SCAN_PASSIVE_FULL_DWELL_SCAN;
                 scan.dwell_time[IPW_SCAN_PASSIVE_FULL_DWELL_SCAN] =
-                        cpu_to_le16(120);
+                        cpu_to_le16(ipw_passive_dwell_time(priv));
                 ipw_add_scan_channels(priv, &scan, scan_type);
                 goto send_request;
         }
 
         /* Use active scan by default. */
-        if (priv->config & CFG_SPEED_SCAN)
+        if (priv->config & CFG_SPEED_SCAN)
                 scan.dwell_time[IPW_SCAN_ACTIVE_BROADCAST_SCAN] =
                         cpu_to_le16(30);
         else
@@ -6333,7 +6348,8 @@ static int ipw_request_scan_helper(struct ipw_priv *priv, int type, int direct)
         scan.dwell_time[IPW_SCAN_ACTIVE_BROADCAST_AND_DIRECT_SCAN] =
                 cpu_to_le16(20);
 
-        scan.dwell_time[IPW_SCAN_PASSIVE_FULL_DWELL_SCAN] = cpu_to_le16(120);
+        scan.dwell_time[IPW_SCAN_PASSIVE_FULL_DWELL_SCAN] =
+                cpu_to_le16(ipw_passive_dwell_time(priv));
         scan.dwell_time[IPW_SCAN_ACTIVE_DIRECT_SCAN] = cpu_to_le16(20);
 
 #ifdef CONFIG_IPW2200_MONITOR
diff --git a/drivers/net/wireless/ipw2x00/ipw2200.h b/drivers/net/wireless/ipw2x00/ipw2200.h
index 0a84d52147bd..277b274d4be5 100644
--- a/drivers/net/wireless/ipw2x00/ipw2200.h
+++ b/drivers/net/wireless/ipw2x00/ipw2200.h
@@ -245,6 +245,7 @@ enum connection_manager_assoc_states {
 #define HOST_NOTIFICATION_S36_MEASUREMENT_REFUSED       31
 
 #define HOST_NOTIFICATION_STATUS_BEACON_MISSING         1
+#define IPW_MB_SCAN_CANCEL_THRESHOLD                    3
 #define IPW_MB_ROAMING_THRESHOLD_MIN                    1
 #define IPW_MB_ROAMING_THRESHOLD_DEFAULT                8
 #define IPW_MB_ROAMING_THRESHOLD_MAX                    30