diff --git a/net/mac80211/chan.c b/net/mac80211/chan.c
index 038f249..2e6faed 100644
--- a/net/mac80211/chan.c
+++ b/net/mac80211/chan.c
@@ -193,6 +193,7 @@
 	if (ctx->refcount > 0) {
 		ieee80211_recalc_chanctx_chantype(sdata->local, ctx);
 		ieee80211_recalc_smps_chanctx(local, ctx);
+		ieee80211_recalc_radar_chanctx(local, ctx);
 	}
 }
 
@@ -216,6 +217,37 @@
 		ieee80211_free_chanctx(local, ctx);
 }
 
+void ieee80211_recalc_radar_chanctx(struct ieee80211_local *local,
+				    struct ieee80211_chanctx *chanctx)
+{
+	struct ieee80211_sub_if_data *sdata;
+	bool radar_enabled = false;
+
+	lockdep_assert_held(&local->chanctx_mtx);
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
+		if (sdata->radar_required) {
+			radar_enabled = true;
+			break;
+		}
+	}
+	rcu_read_unlock();
+
+	if (radar_enabled == chanctx->conf.radar_enabled)
+		return;
+
+	chanctx->conf.radar_enabled = radar_enabled;
+	local->radar_detect_enabled = chanctx->conf.radar_enabled;
+
+	if (!local->use_chanctx) {
+		local->hw.conf.radar_enabled = chanctx->conf.radar_enabled;
+		ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
+	}
+
+	drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RADAR);
+}
+
 void ieee80211_recalc_smps_chanctx(struct ieee80211_local *local,
 				   struct ieee80211_chanctx *chanctx)
 {
@@ -331,6 +363,7 @@
 	}
 
 	ieee80211_recalc_smps_chanctx(local, ctx);
+	ieee80211_recalc_radar_chanctx(local, ctx);
  out:
 	mutex_unlock(&local->chanctx_mtx);
 	return ret;