mac80211: improve IBSS scanning

When IBSS is fixed to a frequency, it can still
scan to try to find the right BSSID. This makes
sense if the BSSID isn't also fixed, but it need
not scan all channels -- just one is sufficient.
Make it do that by moving the scan setup code to
ieee80211_request_internal_scan() and include
a channel variable setting.

Note that this can be further improved to start
the IBSS right away if both frequency and BSSID
are fixed.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 6 insertions, 3 deletions

diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c
index c585fced8584..ba752362b2b2 100644
--- a/net/mac80211/ibss.c
+++ b/net/mac80211/ibss.c
@@ -488,7 +488,9 @@ static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
         printk(KERN_DEBUG "%s: No active IBSS STAs - trying to scan for other "
                "IBSS networks with same SSID (merge)\n", sdata->name);
 
-        ieee80211_request_internal_scan(sdata, ifibss->ssid, ifibss->ssid_len);
+        ieee80211_request_internal_scan(sdata,
+                        ifibss->ssid, ifibss->ssid_len,
+                        ifibss->fixed_channel ? ifibss->channel : NULL);
 }
 
 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
@@ -595,8 +597,9 @@ static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
                 printk(KERN_DEBUG "%s: Trigger new scan to find an IBSS to "
                        "join\n", sdata->name);
 
-                ieee80211_request_internal_scan(sdata, ifibss->ssid,
-                                                ifibss->ssid_len);
+                ieee80211_request_internal_scan(sdata,
+                                ifibss->ssid, ifibss->ssid_len,
+                                ifibss->fixed_channel ? ifibss->channel : NULL);
         } else {
                 int interval = IEEE80211_SCAN_INTERVAL;