diff --git a/src/ap/acs.c b/src/ap/acs.c
index f12539fcd..232afa890 100644
--- a/src/ap/acs.c
+++ b/src/ap/acs.c
@@ -862,6 +862,7 @@ static void acs_study(struct hostapd_iface *iface)
 	}
 
 	iface->conf->channel = ideal_chan->chan;
+	iface->freq = ideal_chan->freq;
 
 	if (iface->conf->ieee80211ac || iface->conf->ieee80211ax)
 		acs_adjust_center_freq(iface);
diff --git a/src/ap/hostapd.c b/src/ap/hostapd.c
index 368643867..b428bb163 100644
--- a/src/ap/hostapd.c
+++ b/src/ap/hostapd.c
@@ -1572,6 +1572,51 @@ static int setup_interface(struct hostapd_iface *iface)
 }
 
 
+static int configured_fixed_chan_to_freq(struct hostapd_iface *iface)
+{
+	int freq, i, j;
+
+	if (!iface->conf->channel)
+		return 0;
+	if (iface->conf->op_class) {
+		freq = ieee80211_chan_to_freq(NULL, iface->conf->op_class,
+					      iface->conf->channel);
+		if (freq < 0) {
+			wpa_printf(MSG_INFO,
+				   "Could not convert op_class %u channel %u to operating frequency",
+				   iface->conf->op_class, iface->conf->channel);
+			return -1;
+		}
+		iface->freq = freq;
+		return 0;
+	}
+
+	/* Old configurations using only 2.4/5/60 GHz bands may not specify the
+	 * op_class parameter. Select a matching channel from the configured
+	 * mode using the channel parameter for these cases.
+	 */
+	for (j = 0; j < iface->num_hw_features; j++) {
+		struct hostapd_hw_modes *mode = &iface->hw_features[j];
+
+		if (iface->conf->hw_mode != HOSTAPD_MODE_IEEE80211ANY &&
+		    iface->conf->hw_mode != mode->mode)
+			continue;
+		for (i = 0; i < mode->num_channels; i++) {
+			struct hostapd_channel_data *chan = &mode->channels[i];
+
+			if (chan->chan == iface->conf->channel &&
+			    !is_6ghz_freq(chan->freq)) {
+				iface->freq = chan->freq;
+				return 0;
+			}
+		}
+	}
+
+	wpa_printf(MSG_INFO, "Could not determine operating frequency");
+	return -1;
+}
+
+
 static int setup_interface2(struct hostapd_iface *iface)
 {
 	iface->wait_channel_update = 0;
@@ -1580,7 +1625,13 @@ static int setup_interface2(struct hostapd_iface *iface)
 		/* Not all drivers support this yet, so continue without hw
 		 * feature data. */
 	} else {
-		int ret = hostapd_select_hw_mode(iface);
+		int ret;
+
+		ret = configured_fixed_chan_to_freq(iface);
+		if (ret < 0)
+			goto fail;
+
+		ret = hostapd_select_hw_mode(iface);
 		if (ret < 0) {
 			wpa_printf(MSG_ERROR, "Could not select hw_mode and "
 				   "channel. (%d)", ret);
@@ -1869,7 +1920,6 @@ static int hostapd_setup_interface_complete_sync(struct hostapd_iface *iface,
 		int res;
 #endif /* NEED_AP_MLME */
 
-		iface->freq = hostapd_hw_get_freq(hapd, iface->conf->channel);
 		wpa_printf(MSG_DEBUG, "Mode: %s  Channel: %d  "
 			   "Frequency: %d MHz",
 			   hostapd_hw_mode_txt(iface->conf->hw_mode),
diff --git a/src/ap/hw_features.c b/src/ap/hw_features.c
index d8accc51a..a8bec4fcd 100644
--- a/src/ap/hw_features.c
+++ b/src/ap/hw_features.c
@@ -922,9 +922,7 @@ int hostapd_acs_completed(struct hostapd_iface *iface, int err)
 	case HOSTAPD_CHAN_VALID:
 		wpa_msg(iface->bss[0]->msg_ctx, MSG_INFO,
 			ACS_EVENT_COMPLETED "freq=%d channel=%d",
-			hostapd_hw_get_freq(iface->bss[0],
-					    iface->conf->channel),
-			iface->conf->channel);
+			iface->freq, iface->conf->channel);
 		break;
 	case HOSTAPD_CHAN_ACS:
 		wpa_printf(MSG_ERROR, "ACS error - reported complete, but no result available");
@@ -964,7 +962,6 @@ out:
 int hostapd_select_hw_mode(struct hostapd_iface *iface)
 {
 	int i;
-	int freq = -1;
 
 	if (iface->num_hw_features < 1)
 		return -1;
@@ -981,15 +978,13 @@ int hostapd_select_hw_mode(struct hostapd_iface *iface)
 	}
 
 	iface->current_mode = NULL;
-	if (iface->conf->channel && iface->conf->op_class)
-		freq = ieee80211_chan_to_freq(NULL, iface->conf->op_class,
-					      iface->conf->channel);
 	for (i = 0; i < iface->num_hw_features; i++) {
 		struct hostapd_hw_modes *mode = &iface->hw_features[i];
 		if (mode->mode == iface->conf->hw_mode) {
-			if (freq > 0 && !hw_get_chan(mode->mode, freq,
-						     iface->hw_features,
-						     iface->num_hw_features))
+			if (iface->freq > 0 &&
+			    !hw_get_chan(mode->mode, iface->freq,
+					 iface->hw_features,
+					 iface->num_hw_features))
 				continue;
 			iface->current_mode = mode;
 			break;