cfg80211: track monitor channel

Make it even more obvious we support single
monitor channel. This will allow us to remove
.get_channel.

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

3 files changed, 18 insertions, 2 deletions

diff --git a/net/wireless/chan.c b/net/wireless/chan.c
index 019401b0b5e3..434c56b92c3c 100644
--- a/net/wireless/chan.c
+++ b/net/wireless/chan.c
@@ -82,6 +82,7 @@ int cfg80211_set_monitor_channel(struct cfg80211_registered_device *rdev,
                                  int freq, enum nl80211_channel_type chantype)
 {
         struct ieee80211_channel *chan;
+        int err;
 
         if (!rdev->ops->set_monitor_channel)
                 return -EOPNOTSUPP;
@@ -92,7 +93,13 @@ int cfg80211_set_monitor_channel(struct cfg80211_registered_device *rdev,
         if (!chan)
                 return -EINVAL;
 
-        return rdev->ops->set_monitor_channel(&rdev->wiphy, chan, chantype);
+        err = rdev->ops->set_monitor_channel(&rdev->wiphy, chan, chantype);
+        if (!err) {
+                rdev->monitor_channel = chan;
+                rdev->monitor_channel_type = chantype;
+        }
+
+        return err;
 }
 
 void
diff --git a/net/wireless/core.c b/net/wireless/core.c
index 8412da7d0f25..1b5daa73b3a9 100644
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -730,9 +730,15 @@ void cfg80211_update_iface_num(struct cfg80211_registered_device *rdev,
                 rdev->num_running_monitor_ifaces += num;
 
         has_monitors_only_new = cfg80211_has_monitors_only(rdev);
-        if (has_monitors_only_new != has_monitors_only_old)
+        if (has_monitors_only_new != has_monitors_only_old) {
                 rdev->ops->set_monitor_enabled(&rdev->wiphy,
                                                has_monitors_only_new);
+
+                if (!has_monitors_only_new) {
+                        rdev->monitor_channel = NULL;
+                        rdev->monitor_channel_type = NL80211_CHAN_NO_HT;
+                }
+        }
 }
 
 static int cfg80211_netdev_notifier_call(struct notifier_block *nb,
diff --git a/net/wireless/core.h b/net/wireless/core.h
index 99acd51343b1..d5efe1b0a8f7 100644
--- a/net/wireless/core.h
+++ b/net/wireless/core.h
@@ -59,6 +59,9 @@ struct cfg80211_registered_device {
         int num_running_ifaces;
         int num_running_monitor_ifaces;
 
+        struct ieee80211_channel *monitor_channel;
+        enum nl80211_channel_type monitor_channel_type;
+
         /* BSSes/scanning */
         spinlock_t bss_lock;
         struct list_head bss_list;