Fan kickstart power option

Marlin/Configuration_adv.h

@@ -552,10 +552,14 @@
   #endif
 #endif
 
-// When first starting the main fan, run it at full speed for the
-// given number of milliseconds.  This gets the fan spinning reliably
-// before setting a PWM value. (Does not work with software PWM for fan on Sanguinololu)
-//#define FAN_KICKSTART_TIME 100
+/**
+ * Fan Kickstart
+ * When part cooling or controller fans first start, run at a speed that
+ * gets it spinning reliably for a short time before setting the requested speed.
+ * (Does not work on Sanguinololu with FAN_SOFT_PWM.)
+ */
+//#define FAN_KICKSTART_TIME  100  // (ms)
+//#define FAN_KICKSTART_POWER 180  // 64-255
 
 // Some coolers may require a non-zero "off" state.
 //#define FAN_OFF_PWM  1

Marlin/src/feature/controllerfan.cpp

@@ -85,10 +85,10 @@ void ControllerFan::update() {
       if (speed != FAN_OFF_PWM) {
         if (!fan_kick_end) {
           fan_kick_end = ms + FAN_KICKSTART_TIME; // May be longer based on slow update interval for controller fn check. Sets minimum
-          speed = 255;
+          speed = FAN_KICKSTART_POWER;
         }
         else if (PENDING(ms, fan_kick_end))
-          speed = 255;
+          speed = FAN_KICKSTART_POWER;
       }
       else
         fan_kick_end = 0;

Marlin/src/inc/Conditionals_adv.h

@@ -1074,3 +1074,8 @@
 #if ANY(DISABLE_INACTIVE_X, DISABLE_INACTIVE_Y, DISABLE_INACTIVE_Z, DISABLE_INACTIVE_I, DISABLE_INACTIVE_J, DISABLE_INACTIVE_K, DISABLE_INACTIVE_U, DISABLE_INACTIVE_V, DISABLE_INACTIVE_W, DISABLE_INACTIVE_E)
   #define HAS_DISABLE_INACTIVE_AXIS 1
 #endif
+
+// Fan Kickstart
+#if FAN_KICKSTART_TIME && !defined(FAN_KICKSTART_POWER)
+  #define FAN_KICKSTART_POWER 180
+#endif

Marlin/src/inc/SanityCheck.h

@@ -1513,6 +1513,11 @@ static_assert(Y_MAX_LENGTH >= Y_BED_SIZE, "Movement bounds (Y_MIN_POS, Y_MAX_POS
   #error "To use BED_LIMIT_SWITCHING you must disable PIDTEMPBED."
 #endif
 
+// Fan Kickstart
+#if FAN_KICKSTART_TIME && defined(FAN_KICKSTART_POWER) && !WITHIN(FAN_KICKSTART_POWER, 64, 255)
+  #error "FAN_KICKSTART_POWER must be an integer from 64 to 255."
+#endif
+
 /**
  * Synchronous M106/M107 checks
  */

Marlin/src/module/planner.cpp

@@ -1309,10 +1309,10 @@ void Planner::recalculate(TERN_(HINTS_SAFE_EXIT_SPEED, const_float_t safe_exit_s
       if (fan_speed[f]) {
         if (fan_kick_end[f] == 0) {
           fan_kick_end[f] = ms + FAN_KICKSTART_TIME;
-          fan_speed[f] = 255;
+          fan_speed[f] = FAN_KICKSTART_POWER;
         }
         else if (PENDING(ms, fan_kick_end[f]))
-          fan_speed[f] = 255;
+          fan_speed[f] = FAN_KICKSTART_POWER;
       }
       else
         fan_kick_end[f] = 0;