Add POWER_OFF_DELAY option (#19987)

Co-authored-by: Scott Lahteine <thinkyhead@users.noreply.github.com>

Marlin/Configuration.h

@@ -344,9 +344,10 @@
     #define AUTO_POWER_E_FANS
     #define AUTO_POWER_CONTROLLERFAN
     #define AUTO_POWER_CHAMBER_FAN
-    //#define AUTO_POWER_E_TEMP        50 // (°C) Turn on PSU over this temperature
-    //#define AUTO_POWER_CHAMBER_TEMP  30 // (°C) Turn on PSU over this temperature
-    #define POWER_TIMEOUT 30
+    //#define AUTO_POWER_E_TEMP        50 // (°C) Turn on PSU if any extruder is over this temperature
+    //#define AUTO_POWER_CHAMBER_TEMP  30 // (°C) Turn on PSU if the chamber is over this temperature
+    #define POWER_TIMEOUT              30 // (s) Turn off power if the machine is idle for this duration
+    //#define POWER_OFF_DELAY          60 // (s) Delay of poweroff after M81 command. Useful to let fans run for extra time.
   #endif
 #endif
 

Marlin/src/MarlinCore.h

@@ -94,9 +94,11 @@ extern bool wait_for_heatup;
   #if ENABLED(AUTO_POWER_CONTROL)
     #define PSU_ON()       powerManager.power_on()
     #define PSU_OFF()      powerManager.power_off()
+    #define PSU_OFF_SOON() powerManager.power_off_soon()
   #else
     #define PSU_ON()     PSU_PIN_ON()
     #define PSU_OFF()    PSU_PIN_OFF()
+    #define PSU_OFF_SOON PSU_OFF
   #endif
 #endif
 

Marlin/src/feature/power.cpp

@@ -126,4 +126,12 @@ void Power::power_off() {
   }
 }
 
+void Power::power_off_soon() {
+  #if POWER_OFF_DELAY
+    lastPowerOn = millis() - SEC_TO_MS(POWER_TIMEOUT) + SEC_TO_MS(POWER_OFF_DELAY);
+  #else
+    power_off();
+  #endif
+}
+
 #endif // AUTO_POWER_CONTROL

Marlin/src/feature/power.h

@@ -32,6 +32,7 @@ class Power {
     static void check();
     static void power_on();
     static void power_off();
+    static void power_off_soon();
   private:
     static millis_t lastPowerOn;
     static bool is_power_needed();

Marlin/src/gcode/control/M80_M81.cpp

@@ -105,7 +105,7 @@ void GcodeSuite::M81() {
   #if HAS_SUICIDE
     suicide();
   #elif ENABLED(PSU_CONTROL)
-    PSU_OFF();
+    PSU_OFF_SOON();
   #endif
 
   LCD_MESSAGEPGM_P(PSTR(MACHINE_NAME " " STR_OFF "."));

Marlin/src/inc/Conditionals_post.h

@@ -416,9 +416,14 @@
   #endif
 #endif
 
-#if !defined(PSU_POWERUP_DELAY) && ENABLED(PSU_CONTROL)
+#if ENABLED(PSU_CONTROL)
+  #ifndef PSU_POWERUP_DELAY
     #define PSU_POWERUP_DELAY 250
   #endif
+  #ifndef POWER_OFF_DELAY
+    #define POWER_OFF_DELAY   0
+  #endif
+#endif
 
 /**
  * Temp Sensor defines

Marlin/src/inc/SanityCheck.h

@@ -3016,9 +3016,9 @@ static_assert(   _ARR_TEST(3,0) && _ARR_TEST(3,1) && _ARR_TEST(3,2)
     #error "PSU_CONTROL requires PSU_ACTIVE_STATE to be defined as 'HIGH' or 'LOW'."
   #elif !PIN_EXISTS(PS_ON)
     #error "PSU_CONTROL requires PS_ON_PIN."
+  #elif POWER_OFF_DELAY < 0
+    #error "POWER_OFF_DELAY must be a positive value."
   #endif
-#elif ENABLED(AUTO_POWER_CONTROL)
-  #error "AUTO_POWER_CONTROL requires PSU_CONTROL."
 #endif
 
 #if HAS_CUTTER