From f7dade8c2c83257df8cc0e32d84334e400161aaf Mon Sep 17 00:00:00 2001
From: Giuliano Zaro <3684609+GMagician@users.noreply.github.com>
Date: Thu, 20 Aug 2020 03:11:20 +0200
Subject: [PATCH] Configurable number of M106 fans (#18883)

---
 Marlin/Configuration.h                    |  4 ++++
 Marlin/src/inc/Conditionals_post.h        | 22 +++++++++++++++++++---
 Marlin/src/inc/SanityCheck.h              |  7 +++++++
 Marlin/src/module/temperature.cpp         |  2 +-
 Marlin/src/pins/sam/pins_CNCONTROLS_15D.h |  2 +-
 5 files changed, 32 insertions(+), 5 deletions(-)

diff --git a/Marlin/Configuration.h b/Marlin/Configuration.h
index 24d7c46a68..986b9efb65 100644
--- a/Marlin/Configuration.h
+++ b/Marlin/Configuration.h
@@ -2275,6 +2275,10 @@
 
 // @section extras
 
+// Set number of user-controlled fans. Disable to use all board-defined fans.
+// :[1,2,3,4,5,6,7,8]
+//#define NUM_M106_FANS 1
+
 // Increase the FAN PWM frequency. Removes the PWM noise but increases heating in the FET/Arduino
 //#define FAST_PWM_FAN
 
diff --git a/Marlin/src/inc/Conditionals_post.h b/Marlin/src/inc/Conditionals_post.h
index 29ab2cfc29..5d7322753f 100644
--- a/Marlin/src/inc/Conditionals_post.h
+++ b/Marlin/src/inc/Conditionals_post.h
@@ -1876,12 +1876,28 @@
   #undef AUTO_POWER_CHAMBER_FAN
 #endif
 
-// Other fans
+// Print Cooling fans (limit)
+#ifdef NUM_M106_FANS
+  #define MAX_FANS NUM_M106_FANS
+#else
+  #define MAX_FANS 8  // Max supported fans
+#endif
+
+#define _NOT_E_AUTO(N,F) (E##N##_AUTO_FAN_PIN != FAN##F##_PIN)
+#define _HAS_FAN(F) (PIN_EXISTS(FAN##F) \
+                     && CONTROLLER_FAN_PIN != FAN##F##_PIN \
+                     && _NOT_E_AUTO(0,F) \
+                     && _NOT_E_AUTO(1,F) \
+                     && _NOT_E_AUTO(2,F) \
+                     && _NOT_E_AUTO(3,F) \
+                     && _NOT_E_AUTO(4,F) \
+                     && _NOT_E_AUTO(5,F) \
+                     && _NOT_E_AUTO(6,F) \
+                     && _NOT_E_AUTO(7,F) \
+                     && F < MAX_FANS)
 #if PIN_EXISTS(FAN)
   #define HAS_FAN0 1
 #endif
-#define _NOT_E_AUTO(N,F) (E##N##_AUTO_FAN_PIN != FAN##F##_PIN)
-#define _HAS_FAN(F) (PIN_EXISTS(FAN##F) && CONTROLLER_FAN_PIN != FAN##F##_PIN && _NOT_E_AUTO(0,F) && _NOT_E_AUTO(1,F) && _NOT_E_AUTO(2,F) && _NOT_E_AUTO(3,F) && _NOT_E_AUTO(4,F) && _NOT_E_AUTO(5,F) && _NOT_E_AUTO(6,F) && _NOT_E_AUTO(7,F))
 #if _HAS_FAN(1)
   #define HAS_FAN1 1
 #endif
diff --git a/Marlin/src/inc/SanityCheck.h b/Marlin/src/inc/SanityCheck.h
index 6fcd867981..d31a826778 100644
--- a/Marlin/src/inc/SanityCheck.h
+++ b/Marlin/src/inc/SanityCheck.h
@@ -1106,6 +1106,13 @@ static_assert(Y_MAX_LENGTH >= Y_BED_SIZE, "Movement bounds (Y_MIN_POS, Y_MAX_POS
   #error "FANMUX0_PIN and FANMUX1_PIN must be set before FANMUX2_PIN can be set."
 #endif
 
+/**
+ * Limited user-controlled fans
+ */
+#if NUM_M106_FANS > FAN_COUNT
+  #error "The selected board doesn't support enough user-controlled fans. Reduce NUM_M106_FANS."
+#endif
+
 /**
  * Limited number of servos
  */
diff --git a/Marlin/src/module/temperature.cpp b/Marlin/src/module/temperature.cpp
index a217fc9ab8..1208e4e995 100644
--- a/Marlin/src/module/temperature.cpp
+++ b/Marlin/src/module/temperature.cpp
@@ -195,7 +195,7 @@ const char str_t_thermal_runaway[] PROGMEM = STR_T_THERMAL_RUNAWAY,
   #endif
 
   #if ENABLED(ADAPTIVE_FAN_SLOWING)
-    uint8_t Temperature::fan_speed_scaler[FAN_COUNT] = ARRAY_N(FAN_COUNT, 128, 128, 128, 128, 128, 128);
+    uint8_t Temperature::fan_speed_scaler[FAN_COUNT] = ARRAY_N(FAN_COUNT, 128, 128, 128, 128, 128, 128, 128, 128);
   #endif
 
   /**
diff --git a/Marlin/src/pins/sam/pins_CNCONTROLS_15D.h b/Marlin/src/pins/sam/pins_CNCONTROLS_15D.h
index b977ad1aba..a2094bee4d 100644
--- a/Marlin/src/pins/sam/pins_CNCONTROLS_15D.h
+++ b/Marlin/src/pins/sam/pins_CNCONTROLS_15D.h
@@ -92,7 +92,7 @@
 //
 // Fans
 //
-//#define FAN0_PIN                             8
+//#define FAN_PIN                              8
 
 //
 // Auto fans