cfg80211: set initial monitor channel

Implements behaviour seen in mac80211. A running
monitor always has a channel - even before
.set_channel. This way we won't break current
behaviour.

Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/net/wireless/core.c b/net/wireless/core.c
index 1b5daa7..580551e 100644 (file)
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -717,6 +717,35 @@ static struct device_type wiphy_type = {
        .name   = "wlan",
 };
 
+static struct ieee80211_channel *
+cfg80211_get_any_chan(struct cfg80211_registered_device *rdev)
+{
+       struct ieee80211_supported_band *sband;
+       int i;
+
+       for (i = 0; i < IEEE80211_NUM_BANDS; i++) {
+               sband = rdev->wiphy.bands[i];
+               if (sband && sband->n_channels > 0)
+                       return &sband->channels[0];
+       }
+
+       return NULL;
+}
+
+static void cfg80211_init_mon_chan(struct cfg80211_registered_device *rdev)
+{
+       struct ieee80211_channel *chan;
+
+       chan = cfg80211_get_any_chan(rdev);
+       if (WARN_ON(!chan))
+               return;
+
+       mutex_lock(&rdev->devlist_mtx);
+       WARN_ON(cfg80211_set_monitor_channel(rdev, chan->center_freq,
+                                            NL80211_CHAN_NO_HT));
+       mutex_unlock(&rdev->devlist_mtx);
+}
+
 void cfg80211_update_iface_num(struct cfg80211_registered_device *rdev,
                               enum nl80211_iftype iftype, int num)
 {
@@ -737,6 +766,8 @@ void cfg80211_update_iface_num(struct cfg80211_registered_device *rdev,
                if (!has_monitors_only_new) {
                        rdev->monitor_channel = NULL;
                        rdev->monitor_channel_type = NL80211_CHAN_NO_HT;
+               } else {
+                       cfg80211_init_mon_chan(rdev);
                }
        }
 }