diff --git a/core/wma/src/wma_dev_if.c b/core/wma/src/wma_dev_if.c
index cdd1826187c4..7a5c7db48df0 100644
--- a/core/wma/src/wma_dev_if.c
+++ b/core/wma/src/wma_dev_if.c
@@ -2361,6 +2361,7 @@ QDF_STATUS wma_vdev_start(tp_wma_handle wma,
 	uint16_t bw_val;
 	struct wma_txrx_node *iface = &wma->interfaces[req->vdev_id];
 	struct wma_target_req *req_msg;
+	uint32_t chan_mode;
 
 	mac_ctx = cds_get_context(QDF_MODULE_ID_PE);
 	if (mac_ctx == NULL) {
@@ -2368,6 +2369,14 @@ QDF_STATUS wma_vdev_start(tp_wma_handle wma,
 		return QDF_STATUS_E_FAILURE;
 	}
 
+	chan_mode = wma_chan_phy_mode(req->chan, req->chan_width,
+					     req->dot11_mode);
+
+	if (chan_mode == MODE_UNKNOWN) {
+		WMA_LOGE("%s: invalid phy mode!", __func__);
+		return QDF_STATUS_E_FAILURE;
+	}
+
 	if (!isRestart &&
 	    qdf_atomic_read(&iface->bss_status) == WMA_BSS_STATUS_STARTED) {
 		req_msg = wma_find_vdev_req(wma, req->vdev_id,
@@ -2393,8 +2402,8 @@ QDF_STATUS wma_vdev_start(tp_wma_handle wma,
 
 	/* Fill channel info */
 	params.chan_freq = cds_chan_to_freq(req->chan);
-	params.chan_mode = wma_chan_phy_mode(req->chan, req->chan_width,
-					     req->dot11_mode);
+	params.chan_mode = chan_mode;
+
 	intr[params.vdev_id].chanmode = params.chan_mode;
 	intr[params.vdev_id].ht_capable = req->ht_capable;
 	intr[params.vdev_id].vht_capable = req->vht_capable;
diff --git a/core/wma/src/wma_scan_roam.c b/core/wma/src/wma_scan_roam.c
index 32445ddec891..b7e60d231892 100644
--- a/core/wma/src/wma_scan_roam.c
+++ b/core/wma/src/wma_scan_roam.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2017 The Linux Foundation. All rights reserved.
+ * Copyright (c) 2013-2018 The Linux Foundation. All rights reserved.
  *
  * Previously licensed under the ISC license by Qualcomm Atheros, Inc.
  *
@@ -3308,7 +3308,16 @@ static QDF_STATUS wma_switch_channel(tp_wma_handle wma,
 	pmac = cds_get_context(QDF_MODULE_ID_PE);
 
 	if (pmac == NULL) {
-		WMA_LOGE("%s: vdev start failed as pmac is NULL", __func__);
+		WMA_LOGE("%s: channel switch failed as pmac is NULL",
+			 __func__);
+		return QDF_STATUS_E_FAILURE;
+	}
+
+	chanmode = wma_chan_phy_mode(req->chan, req->chan_width,
+				     req->dot11_mode);
+
+	if (chanmode == MODE_UNKNOWN) {
+		WMA_LOGE("%s: invalid phy mode!", __func__);
 		return QDF_STATUS_E_FAILURE;
 	}
 
@@ -3325,8 +3334,6 @@ static QDF_STATUS wma_switch_channel(tp_wma_handle wma,
 
 	/* Fill channel info */
 	cmd->mhz = cds_chan_to_freq(req->chan);
-	chanmode = wma_chan_phy_mode(req->chan, req->chan_width,
-				    req->dot11_mode);
 
 	intr[req->vdev_id].chanmode = chanmode; /* save channel mode */
 	intr[req->vdev_id].ht_capable = req->ht_capable;