cfg80211: add regulatory hint disconnect support

This adds a new regulatory hint to be used when we know all
devices have been disconnected and idle. This can happen
when we suspend, for instance. When we disconnect we can
no longer assume the same regulatory rules learned from
a country IE or beacon hints are applicable so restore
regulatory settings to an initial state.

Since driver hints are cached on the wiphy that called
the hint, those hints are not reproduced onto cfg80211
as the wiphy will respect its own wiphy->regd regardless.

Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 40 insertions, 0 deletions

diff --git a/net/wireless/sme.c b/net/wireless/sme.c
index 745c37e7992e..17fde0da1b08 100644
--- a/net/wireless/sme.c
+++ b/net/wireless/sme.c
@@ -34,6 +34,44 @@ struct cfg80211_conn {
 	bool auto_auth, prev_bssid_valid;
 };
 
+bool cfg80211_is_all_idle(void)
+{
+	struct cfg80211_registered_device *rdev;
+	struct wireless_dev *wdev;
+	bool is_all_idle = true;
+
+	mutex_lock(&cfg80211_mutex);
+
+	/*
+	 * All devices must be idle as otherwise if you are actively
+	 * scanning some new beacon hints could be learned and would
+	 * count as new regulatory hints.
+	 */
+	list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
+		cfg80211_lock_rdev(rdev);
+		list_for_each_entry(wdev, &rdev->netdev_list, list) {
+			wdev_lock(wdev);
+			if (wdev->sme_state != CFG80211_SME_IDLE)
+				is_all_idle = false;
+			wdev_unlock(wdev);
+		}
+		cfg80211_unlock_rdev(rdev);
+	}
+
+	mutex_unlock(&cfg80211_mutex);
+
+	return is_all_idle;
+}
+
+static void disconnect_work(struct work_struct *work)
+{
+	if (!cfg80211_is_all_idle())
+		return;
+
+	regulatory_hint_disconnect();
+}
+
+static DECLARE_WORK(cfg80211_disconnect_work, disconnect_work);
 
 static int cfg80211_conn_scan(struct wireless_dev *wdev)
 {
@@ -658,6 +696,8 @@ void __cfg80211_disconnected(struct net_device *dev, const u8 *ie,
 	wireless_send_event(dev, SIOCGIWAP, &wrqu, NULL);
 	wdev->wext.connect.ssid_len = 0;
 #endif
+
+	schedule_work(&cfg80211_disconnect_work);
 }
 
 void cfg80211_disconnected(struct net_device *dev, u16 reason,