diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index d6c62ee..9d2d2b1 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -4893,12 +4893,17 @@ enum nl80211_smps_mode {
  *	change to the channel status.
  * @NL80211_RADAR_NOP_FINISHED: The Non-Occupancy Period for this channel is
  *	over, channel becomes usable.
+ * @NL80211_RADAR_PRE_CAC_EXPIRED: Channel Availability Check done on this
+ *	non-operating channel is expired and no longer valid. New CAC must
+ *	be done on this channel before starting the operation. This is not
+ *	applicable for ETSI dfs domain where pre-CAC is valid for ever.
  */
 enum nl80211_radar_event {
 	NL80211_RADAR_DETECTED,
 	NL80211_RADAR_CAC_FINISHED,
 	NL80211_RADAR_CAC_ABORTED,
 	NL80211_RADAR_NOP_FINISHED,
+	NL80211_RADAR_PRE_CAC_EXPIRED,
 };
 
 /**
diff --git a/net/wireless/ap.c b/net/wireless/ap.c
index bdad1f9..25666d3 100644
--- a/net/wireless/ap.c
+++ b/net/wireless/ap.c
@@ -32,6 +32,11 @@ int __cfg80211_stop_ap(struct cfg80211_registered_device *rdev,
 		rdev_set_qos_map(rdev, dev, NULL);
 		if (notify)
 			nl80211_send_ap_stopped(wdev);
+
+		/* Should we apply the grace period during beaconing interface
+		 * shutdown also?
+		 */
+		cfg80211_sched_dfs_chan_update(rdev);
 	}
 
 	return err;
diff --git a/net/wireless/chan.c b/net/wireless/chan.c
index 5497d022..099f13c 100644
--- a/net/wireless/chan.c
+++ b/net/wireless/chan.c
@@ -456,6 +456,107 @@ bool cfg80211_chandef_dfs_usable(struct wiphy *wiphy,
 	return (r1 + r2 > 0);
 }
 
+/*
+ * Checks if center frequency of chan falls with in the bandwidth
+ * range of chandef.
+ */
+bool cfg80211_is_sub_chan(struct cfg80211_chan_def *chandef,
+			  struct ieee80211_channel *chan)
+{
+	int width;
+	u32 cf_offset, freq;
+
+	if (chandef->chan->center_freq == chan->center_freq)
+		return true;
+
+	width = cfg80211_chandef_get_width(chandef);
+	if (width <= 20)
+		return false;
+
+	cf_offset = width / 2 - 10;
+
+	for (freq = chandef->center_freq1 - width / 2 + 10;
+	     freq <= chandef->center_freq1 + width / 2 - 10; freq += 20) {
+		if (chan->center_freq == freq)
+			return true;
+	}
+
+	if (!chandef->center_freq2)
+		return false;
+
+	for (freq = chandef->center_freq2 - width / 2 + 10;
+	     freq <= chandef->center_freq2 + width / 2 - 10; freq += 20) {
+		if (chan->center_freq == freq)
+			return true;
+	}
+
+	return false;
+}
+
+bool cfg80211_beaconing_iface_active(struct wireless_dev *wdev)
+{
+	bool active = false;
+
+	ASSERT_WDEV_LOCK(wdev);
+
+	if (!wdev->chandef.chan)
+		return false;
+
+	switch (wdev->iftype) {
+	case NL80211_IFTYPE_AP:
+	case NL80211_IFTYPE_P2P_GO:
+		active = wdev->beacon_interval != 0;
+		break;
+	case NL80211_IFTYPE_ADHOC:
+		active = wdev->ssid_len != 0;
+		break;
+	case NL80211_IFTYPE_MESH_POINT:
+		active = wdev->mesh_id_len != 0;
+		break;
+	case NL80211_IFTYPE_STATION:
+	case NL80211_IFTYPE_OCB:
+	case NL80211_IFTYPE_P2P_CLIENT:
+	case NL80211_IFTYPE_MONITOR:
+	case NL80211_IFTYPE_AP_VLAN:
+	case NL80211_IFTYPE_WDS:
+	case NL80211_IFTYPE_P2P_DEVICE:
+	/* Can NAN type be considered as beaconing interface? */
+	case NL80211_IFTYPE_NAN:
+		break;
+	case NL80211_IFTYPE_UNSPECIFIED:
+	case NUM_NL80211_IFTYPES:
+		WARN_ON(1);
+	}
+
+	return active;
+}
+
+bool cfg80211_any_wiphy_oper_chan(struct wiphy *wiphy,
+				  struct ieee80211_channel *chan)
+{
+	struct wireless_dev *wdev;
+
+	ASSERT_RTNL();
+
+	if (!(chan->flags & IEEE80211_CHAN_RADAR))
+		return false;
+
+	list_for_each_entry(wdev, &wiphy->wdev_list, list) {
+		wdev_lock(wdev);
+		if (!cfg80211_beaconing_iface_active(wdev)) {
+			wdev_unlock(wdev);
+			continue;
+		}
+
+		if (cfg80211_is_sub_chan(&wdev->chandef, chan)) {
+			wdev_unlock(wdev);
+			return true;
+		}
+		wdev_unlock(wdev);
+	}
+
+	return false;
+}
 
 static bool cfg80211_get_chans_dfs_available(struct wiphy *wiphy,
 					     u32 center_freq,
diff --git a/net/wireless/core.h b/net/wireless/core.h
index 58ca206..3b3c991 100644
--- a/net/wireless/core.h
+++ b/net/wireless/core.h
@@ -459,6 +459,16 @@ void cfg80211_set_dfs_state(struct wiphy *wiphy,
 cfg80211_chandef_dfs_cac_time(struct wiphy *wiphy,
 			      const struct cfg80211_chan_def *chandef);
 
+void cfg80211_sched_dfs_chan_update(struct cfg80211_registered_device *rdev);
+
+bool cfg80211_any_wiphy_oper_chan(struct wiphy *wiphy,
+				  struct ieee80211_channel *chan);
+
+bool cfg80211_beaconing_iface_active(struct wireless_dev *wdev);
+
+bool cfg80211_is_sub_chan(struct cfg80211_chan_def *chandef,
+			  struct ieee80211_channel *chan);
+
 static inline unsigned int elapsed_jiffies_msecs(unsigned long start)
 {
 	unsigned long end = jiffies;
diff --git a/net/wireless/ibss.c b/net/wireless/ibss.c
index 364f900..10bf040 100644
--- a/net/wireless/ibss.c
+++ b/net/wireless/ibss.c
@@ -190,6 +190,7 @@ static void __cfg80211_clear_ibss(struct net_device *dev, bool nowext)
 	if (!nowext)
 		wdev->wext.ibss.ssid_len = 0;
 #endif
+	cfg80211_sched_dfs_chan_update(rdev);
 }
 
 void cfg80211_clear_ibss(struct net_device *dev, bool nowext)
diff --git a/net/wireless/mesh.c b/net/wireless/mesh.c
index 2d8518a..ec0b1c2 100644
--- a/net/wireless/mesh.c
+++ b/net/wireless/mesh.c
@@ -262,6 +262,7 @@ int __cfg80211_leave_mesh(struct cfg80211_registered_device *rdev,
 		wdev->beacon_interval = 0;
 		memset(&wdev->chandef, 0, sizeof(wdev->chandef));
 		rdev_set_qos_map(rdev, dev, NULL);
+		cfg80211_sched_dfs_chan_update(rdev);
 	}
 
 	return err;
diff --git a/net/wireless/mlme.c b/net/wireless/mlme.c
index 22b3d99..cd29366 100644
--- a/net/wireless/mlme.c
+++ b/net/wireless/mlme.c
@@ -745,6 +745,12 @@ bool cfg80211_rx_mgmt(struct wireless_dev *wdev, int freq, int sig_mbm,
 }
 EXPORT_SYMBOL(cfg80211_rx_mgmt);
 
+void cfg80211_sched_dfs_chan_update(struct cfg80211_registered_device *rdev)
+{
+	cancel_delayed_work(&rdev->dfs_update_channels_wk);
+	queue_delayed_work(cfg80211_wq, &rdev->dfs_update_channels_wk, 0);
+}
+
 void cfg80211_dfs_channels_update_work(struct work_struct *work)
 {
 	struct delayed_work *delayed_work = to_delayed_work(work);
@@ -755,6 +761,8 @@ void cfg80211_dfs_channels_update_work(struct work_struct *work)
 	struct wiphy *wiphy;
 	bool check_again = false;
 	unsigned long timeout, next_time = 0;
+	unsigned long time_dfs_update;
+	enum nl80211_radar_event radar_event;
 	int bandid, i;
 
 	rdev = container_of(delayed_work, struct cfg80211_registered_device,
@@ -770,11 +778,27 @@ void cfg80211_dfs_channels_update_work(struct work_struct *work)
 		for (i = 0; i < sband->n_channels; i++) {
 			c = &sband->channels[i];
 
-			if (c->dfs_state != NL80211_DFS_UNAVAILABLE)
+			if (!(c->flags & IEEE80211_CHAN_RADAR))
+				continue;
+
+			if (c->dfs_state != NL80211_DFS_UNAVAILABLE &&
+			    c->dfs_state != NL80211_DFS_AVAILABLE)
 				continue;
 
-			timeout = c->dfs_state_entered + msecs_to_jiffies(
-					IEEE80211_DFS_MIN_NOP_TIME_MS);
+			if (c->dfs_state == NL80211_DFS_UNAVAILABLE) {
+				time_dfs_update = IEEE80211_DFS_MIN_NOP_TIME_MS;
+				radar_event = NL80211_RADAR_NOP_FINISHED;
+			} else {
+				if (regulatory_pre_cac_allowed(wiphy) ||
+				    cfg80211_any_wiphy_oper_chan(wiphy, c))
+					continue;
+
+				time_dfs_update = REG_PRE_CAC_EXPIRY_GRACE_MS;
+				radar_event = NL80211_RADAR_PRE_CAC_EXPIRED;
+			}
+
+			timeout = c->dfs_state_entered +
+				  msecs_to_jiffies(time_dfs_update);
 
 			if (time_after_eq(jiffies, timeout)) {
 				c->dfs_state = NL80211_DFS_USABLE;
@@ -784,8 +808,8 @@ void cfg80211_dfs_channels_update_work(struct work_struct *work)
 							NL80211_CHAN_NO_HT);
 
 				nl80211_radar_notify(rdev, &chandef,
-						     NL80211_RADAR_NOP_FINISHED,
-						     NULL, GFP_ATOMIC);
+						     radar_event, NULL,
+						     GFP_ATOMIC);
 				continue;
 			}
 
@@ -810,7 +834,6 @@ void cfg80211_radar_event(struct wiphy *wiphy,
 			  gfp_t gfp)
 {
 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
-	unsigned long timeout;
 
 	trace_cfg80211_radar_event(wiphy, chandef);
 
@@ -820,9 +843,7 @@ void cfg80211_radar_event(struct wiphy *wiphy,
 	 */
 	cfg80211_set_dfs_state(wiphy, chandef, NL80211_DFS_UNAVAILABLE);
 
-	timeout = msecs_to_jiffies(IEEE80211_DFS_MIN_NOP_TIME_MS);
-	queue_delayed_work(cfg80211_wq, &rdev->dfs_update_channels_wk,
-			   timeout);
+	cfg80211_sched_dfs_chan_update(rdev);
 
 	nl80211_radar_notify(rdev, chandef, NL80211_RADAR_DETECTED, NULL, gfp);
 }
@@ -851,6 +872,7 @@ void cfg80211_cac_event(struct net_device *netdev,
 			  msecs_to_jiffies(wdev->cac_time_ms);
 		WARN_ON(!time_after_eq(jiffies, timeout));
 		cfg80211_set_dfs_state(wiphy, chandef, NL80211_DFS_AVAILABLE);
+		cfg80211_sched_dfs_chan_update(rdev);
 		break;
 	case NL80211_RADAR_CAC_ABORTED:
 		break;
diff --git a/net/wireless/reg.c b/net/wireless/reg.c
index 753efcd..e59b192 100644
--- a/net/wireless/reg.c
+++ b/net/wireless/reg.c
@@ -3120,6 +3120,34 @@ bool regulatory_indoor_allowed(void)
 	return reg_is_indoor;
 }
 
+bool regulatory_pre_cac_allowed(struct wiphy *wiphy)
+{
+	const struct ieee80211_regdomain *regd = NULL;
+	const struct ieee80211_regdomain *wiphy_regd = NULL;
+	bool pre_cac_allowed = false;
+
+	rcu_read_lock();
+
+	regd = rcu_dereference(cfg80211_regdomain);
+	wiphy_regd = rcu_dereference(wiphy->regd);
+	if (!wiphy_regd) {
+		if (regd->dfs_region == NL80211_DFS_ETSI)
+			pre_cac_allowed = true;
+
+		rcu_read_unlock();
+
+		return pre_cac_allowed;
+	}
+
+	if (regd->dfs_region == wiphy_regd->dfs_region &&
+	    wiphy_regd->dfs_region == NL80211_DFS_ETSI)
+		pre_cac_allowed = true;
+
+	rcu_read_unlock();
+
+	return pre_cac_allowed;
+}
+
 int __init regulatory_init(void)
 {
 	int err = 0;
diff --git a/net/wireless/reg.h b/net/wireless/reg.h
index f6ced31..ff078f0 100644
--- a/net/wireless/reg.h
+++ b/net/wireless/reg.h
@@ -143,4 +143,18 @@ void regulatory_hint_country_ie(struct wiphy *wiphy,
  */
 bool regulatory_indoor_allowed(void);
 
+/*
+ * Grace period to timeout pre-CAC results on the dfs channels. This timeout
+ * value is used for Non-ETSI domain.
+ * TODO: May be make this timeout available through regdb?
+ */
+#define REG_PRE_CAC_EXPIRY_GRACE_MS 2000
+
+/**
+ * regulatory_pre_cac_allowed - if pre-CAC allowed in the current dfs domain
+ * @wiphy: wiphy for which pre-CAC capability is checked.
+
+ * Pre-CAC is allowed only in ETSI domain.
+ */
+bool regulatory_pre_cac_allowed(struct wiphy *wiphy);
 #endif  /* __NET_WIRELESS_REG_H */
