Index: hostapd-2021-02-20-59e9794c/src/ap/ubus.c
===================================================================
--- hostapd-2021-02-20-59e9794c.orig/src/ap/ubus.c
+++ hostapd-2021-02-20-59e9794c/src/ap/ubus.c
@@ -25,2 +25,3 @@
 #include "airtime_policy.h"
+#include "dfs.h"
 #include "hw_features.h"
@@ -857,6 +858,7 @@ hostapd_switch_chan(struct ubus_context
 	u8 seg0 = 0, seg1 = 0;
 	int ret = UBUS_STATUS_OK;
 	int i;
+	int dfs_range = 0;
 
 	blobmsg_parse(csa_policy, __CSA_MAX, tb, blob_data(msg), blob_len(msg));
 
@@ -912,6 +914,17 @@ hostapd_switch_chan(struct ubus_context
 		break;
 	}
 
+	if (css.freq_params.center_freq1)
+		dfs_range += hostapd_is_dfs_overlap(
+			hapd->iface, chwidth, css.freq_params.center_freq1);
+	else
+		dfs_range += hostapd_is_dfs_overlap(
+			hapd->iface, chwidth, css.freq_params.freq);
+
+	if (css.freq_params.center_freq2)
+		dfs_range += hostapd_is_dfs_overlap(
+			hapd->iface, chwidth, css.freq_params.center_freq2);
+
 	hostapd_set_freq_params(&css.freq_params, iconf->hw_mode,
 				css.freq_params.freq,
 				css.freq_params.channel, iconf->enable_edmg,
@@ -925,6 +938,15 @@ hostapd_switch_chan(struct ubus_context
 				mode ? &mode->he_capab[IEEE80211_MODE_AP] :
 				NULL);
 
+	if (dfs_range) {
+		/* Perform CAC and switch channel */
+		freq_params = malloc(sizeof(*freq_params));
+		memcpy(freq_params, &css.freq_params, sizeof(*freq_params));
+		eloop_register_timeout(0, 1, switch_chan_fallback_cb,
+				       hapd->iface, freq_params);
+		return 0;
+	}
+
 	for (i = 0; i < hapd->iface->num_bss; i++) {
 		struct hostapd_data *bss = hapd->iface->bss[i];