track init as a debug option

Marlin/src/HAL/AVR/fast_pwm.cpp

@@ -24,7 +24,12 @@
 #include "../../inc/MarlinConfigPre.h"
 #include "HAL.h"
 
-static uint16_t timer_freq[5];
+//#define DEBUG_PWM_INIT
+
+#if ENABLED(DEBUG_PWM_INIT)
+  #include "../../core/serial.h"
+  static uint16_t timer_freq[5];
+#endif
 
 struct Timer {
   volatile uint8_t* TCCRnQ[3];  // max 3 TCCR registers per timer
@@ -153,9 +158,10 @@ Timer get_pwm_timer(const pin_t pin) {
 void set_pwm_frequency(const pin_t pin, int f_desired) {
   Timer timer = get_pwm_timer(pin);
   if (timer.n == 0) return; // Don't proceed if protected timer or not recognized
-  timer_freq[timer.n] = f_desired;
-  uint16_t size;
-  if (timer.n == 2) size = 255; else size = 65535;
+
+  TERN_(DEBUG_PWM_INIT, timer_freq[timer.n - 1] = f_desired);
+
+  const uint16_t size = (timer.n == 2) ? 255 : 65535;
 
   uint16_t res = 255;   // resolution (TOP value)
   uint8_t j = 0;        // prescaler index
@@ -242,10 +248,12 @@ void set_pwm_duty(const pin_t pin, const uint16_t v, const uint16_t v_size/*=255
       Timer timer = get_pwm_timer(pin);
       if (timer.n == 0) return; // Don't proceed if protected timer or not recognized
       // Set compare output mode to CLEAR -> SET or SET -> CLEAR (if inverted)
-      if (timer_freq[timer.n] == 0) {           // If the timer is unconfigured and no freq is set then default PWM_FREQUENCY
-        set_pwm_frequency(pin, PWM_FREQUENCY);  // Set the frequency and save the value to the assigned index no.
-        timer_freq[timer.n] = PWM_FREQUENCY;
-      }
+      #if ENABLED(DEBUG_PWM_INIT)
+        if (timer_freq[timer.n - 1] == 0) {       // If the timer is unconfigured and no freq is set then default PWM_FREQUENCY
+          set_pwm_frequency(pin, PWM_FREQUENCY);  // Set the frequency and save the value to the assigned index no.
+          SERIAL_ECHOLNPGM("PWM Timer ", timer.n, " Frequency Not Initialized!");
+        }
+      #endif
       _SET_COMnQ(timer.TCCRnQ, timer.q TERN_(HAS_TCCR2, + (timer.q == 2)), COM_CLEAR_SET + invert); // COM20 is on bit 4 of TCCR2, so +1 for q==2
       const uint16_t top = timer.n == 2 ? TERN(USE_OCR2A_AS_TOP, *timer.OCRnQ[0], 255) : *timer.ICRn;
       _SET_OCRnQ(timer.OCRnQ, timer.q, uint16_t(uint32_t(v) * top / v_size)); // Scale 8/16-bit v to top value