diff --git a/package/kernel/broadcom-wl/files/lib/wifi/broadcom.sh b/package/kernel/broadcom-wl/files/lib/wifi/broadcom.sh
index 69e3132..7fec6aa 100644
--- a/package/kernel/broadcom-wl/files/lib/wifi/broadcom.sh
+++ b/package/kernel/broadcom-wl/files/lib/wifi/broadcom.sh
@@ -201,6 +201,15 @@ enable_broadcom() {
        # Use 'chanspec' instead of 'channel' for 'N' modes (See bcmwifi.h)
        [ ${nmode:-0} -ne 0 -a -n "$band" -a -n "$channel" ] && {
                case "$htmode" in
+                       HT40)
+                               if [ -n "$gmode" ]; then
+                                       [ $channel -lt 7 ] && htmode="HT40+" || htmode="HT40-"
+                               else
+                                       [ $(( ($channel / 4) % 2 )) -eq 1 ] && htmode="HT40+" || htmode="HT40-"
+                               fi
+                       ;;
+               esac
+               case "$htmode" in
                        HT40-)  chanspec=$(printf 0x%x%x%02x $band 0xe $(($channel - 2))); channel=;;
                        HT40+)  chanspec=$(printf 0x%x%x%02x $band 0xd $(($channel + 2))); channel=;;
                        HT20)   chanspec=$(printf 0x%x%x%02x $band 0xb $channel); channel=;;