From 09b72757bbb5d565ace88b33275bc67474163eeb Mon Sep 17 00:00:00 2001
From: Scott Lahteine <thinkyhead@users.noreply.github.com>
Date: Fri, 11 Mar 2022 18:03:20 -0600
Subject: [PATCH] Bool param is 1 with no value

---
 Marlin/src/gcode/probe/M401_M402.cpp | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/Marlin/src/gcode/probe/M401_M402.cpp b/Marlin/src/gcode/probe/M401_M402.cpp
index 7ca4757e7995c..9f45994830438 100644
--- a/Marlin/src/gcode/probe/M401_M402.cpp
+++ b/Marlin/src/gcode/probe/M401_M402.cpp
@@ -36,14 +36,15 @@
  * M401: Deploy and activate the Z probe
  *
  * With BLTOUCH_HS_MODE:
+ *  H       Report the current BLTouch HS mode state
  *  S<bool> Set High Speed (HS) Mode and exit without deploy
  */
 void GcodeSuite::M401() {
-  if (parser.seen('S')) {
+  const bool seenH = parser.seen_test('H'),
+             seenS = parser.seen('S');
+  if (seenH || seenS) {
     #ifdef BLTOUCH_HS_MODE
-      if (parser.has_value()) {  // if no value after "S" than just query
-        bltouch.high_speed_mode = parser.value_bool();
-      }
+      if (seenS) bltouch.high_speed_mode = parser.value_bool();
       SERIAL_ECHO_START();
       SERIAL_ECHOPGM("BLTouch HS mode ");
       serialprintln_onoff(bltouch.high_speed_mode);