Independent Neopixel option (#19115)

Marlin/src/inc/Conditionals_LCD.h

@@ -780,3 +780,8 @@
 #ifndef EXTRUDE_MINTEMP
   #define EXTRUDE_MINTEMP 170
 #endif
+
+// This flag indicates if Neopixel pins are shared or separated  
+#if EITHER(MULTIPLE_NEOPIXEL_TYPES, NEOPIXEL2_INSERIES)
+  #define CONJOINED_NEOPIXEL 1
+#endif

Marlin/src/inc/Conditionals_adv.h

@@ -246,6 +246,28 @@
   #endif
 #endif
 
+#if BOTH(LED_CONTROL_MENU, NEOPIXEL2_SEPARATE)
+  #ifndef LED2_USER_PRESET_RED
+    #define LED2_USER_PRESET_RED       255
+  #endif
+  #ifndef LED2_USER_PRESET_GREEN
+    #define LED2_USER_PRESET_GREEN     255
+  #endif
+  #ifndef LED2_USER_PRESET_BLUE
+    #define LED2_USER_PRESET_BLUE      255
+  #endif
+  #ifndef LED2_USER_PRESET_WHITE
+    #define LED2_USER_PRESET_WHITE     0
+  #endif
+  #ifndef LED2_USER_PRESET_BRIGHTNESS
+    #ifdef NEOPIXEL2_BRIGHTNESS
+      #define LED2_USER_PRESET_BRIGHTNESS NEOPIXEL2_BRIGHTNESS
+    #else
+      #define LED2_USER_PRESET_BRIGHTNESS 255
+    #endif
+  #endif
+#endif
+
 // If platform requires early initialization of watchdog to properly boot
 #if ENABLED(USE_WATCHDOG) && defined(ARDUINO_ARCH_SAM)
   #define EARLY_WATCHDOG 1

Marlin/src/inc/SanityCheck.h

@@ -2120,7 +2120,12 @@ static_assert(hbm[Z_AXIS] >= 0, "HOMING_BUMP_MM.Z must be greater than or equal
   #if !(PIN_EXISTS(NEOPIXEL) && NEOPIXEL_PIXELS > 0)
     #error "NEOPIXEL_LED requires NEOPIXEL_PIN and NEOPIXEL_PIXELS."
   #endif
+  #elif ENABLED(NEOPIXEL2_SEPARATE)
+   #if !(PIN_EXISTS(NEOPIXEL2) && NEOPIXEL2_PIXELS > 0)
+    #error "NEOPIXEL2 requires NEOPIXEL2_PIN and NEOPIXEL2_PIXELS."
+  #endif
 #endif
+
 #undef _RGB_TEST
 
 #if DISABLED(NO_COMPILE_TIME_PWM)