FAST_PWM for STM32F1 (#19952)

Marlin/src/HAL/STM32F1/HAL.h

@@ -244,3 +244,20 @@ void analogWrite(pin_t pin, int pwm_val8); // PWM only! mul by 257 in maple!?
 
 #define PLATFORM_M997_SUPPORT
 void flashFirmware(const int16_t);
+
+#define HAL_CAN_SET_PWM_FREQ   // This HAL supports PWM Frequency adjustment
+
+/**
+ * set_pwm_frequency
+ *  Set the frequency of the timer corresponding to the provided pin
+ *  All Timer PWM pins run at the same frequency
+ */
+void set_pwm_frequency(const pin_t pin, int f_desired);
+
+/**
+ * set_pwm_duty
+ *  Set the PWM duty cycle of the provided pin to the provided value
+ *  Optionally allows inverting the duty cycle [default = false]
+ *  Optionally allows changing the maximum size of the provided value to enable finer PWM duty control [default = 255]
+ */
+void set_pwm_duty(const pin_t pin, const uint16_t v, const uint16_t v_size=255, const bool invert=false);

Marlin/src/HAL/STM32F1/fast_pwm.cpp

@@ -0,0 +1,68 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2020 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#ifdef __STM32F1__
+
+#include "../../inc/MarlinConfigPre.h"
+
+#if NEEDS_HARDWARE_PWM
+
+#include <pwm.h>
+#include "HAL.h"
+#include "timers.h"
+
+void set_pwm_frequency(const pin_t pin, int f_desired) {
+  if (!PWM_PIN(pin)) return;                    // Don't proceed if no hardware timer
+
+  timer_dev *timer = PIN_MAP[pin].timer_device;
+  uint8_t channel = PIN_MAP[pin].timer_channel;
+
+  // Protect used timers
+  if (timer == get_timer_dev(TEMP_TIMER_NUM)) return;
+  if (timer == get_timer_dev(STEP_TIMER_NUM)) return;
+  #if PULSE_TIMER_NUM != STEP_TIMER_NUM
+    if (timer == get_timer_dev(PULSE_TIMER_NUM)) return;
+  #endif
+
+  if (!(timer->regs.bas->SR & TIMER_CR1_CEN))   // Ensure the timer is enabled
+    timer_init(timer);
+
+  timer_set_mode(timer, channel, TIMER_PWM);
+  uint16_t preload = 255;                       // Lock 255 PWM resolution for high frequencies
+  int32_t prescaler = (HAL_TIMER_RATE) / (preload + 1) / f_desired - 1;
+  if (prescaler > 65535) {                      // For low frequencies increase prescaler
+    prescaler = 65535;
+    preload = (HAL_TIMER_RATE) / (prescaler + 1) / f_desired - 1;
+  }
+  if (prescaler < 0) return;                    // Too high frequency
+  timer_set_reload(timer, preload);
+  timer_set_prescaler(timer, prescaler);
+}
+
+void set_pwm_duty(const pin_t pin, const uint16_t v, const uint16_t v_size/*=255*/, const bool invert/*=false*/) {
+  timer_dev *timer = PIN_MAP[pin].timer_device;
+  uint16_t max_val = timer->regs.bas->ARR * v / v_size;
+  if (invert) max_val = v_size - max_val;
+  pwmWrite(pin, max_val);
+}
+
+#endif // NEEDS_HARDWARE_PWM
+#endif // __STM32F1__

Marlin/src/HAL/STM32F1/inc/SanityCheck.h

@@ -25,10 +25,6 @@
  * Test STM32F1-specific configuration values for errors at compile-time.
  */
 
-#if ENABLED(FAST_PWM_FAN) || SPINDLE_LASER_FREQUENCY
-  #error "Features requiring Hardware PWM (FAST_PWM_FAN, SPINDLE_LASER_FREQUENCY) are not yet supported on STM32F1."
-#endif
-
 #if !defined(HAVE_SW_SERIAL) && HAS_TMC_SW_SERIAL
   #warning "With TMC2208/9 consider using SoftwareSerialM with HAVE_SW_SERIAL and appropriate SS_TIMER."
   #error "Missing SoftwareSerial implementation."

Marlin/src/lcd/menu/menu_spindle_laser.cpp

@@ -55,11 +55,9 @@
       #endif
     }
 
-    #if ENABLED(MARLIN_DEV_MODE)
+    #if BOTH(MARLIN_DEV_MODE, HAL_CAN_SET_PWM_FREQ) && defined(SPINDLE_LASER_FREQUENCY)
-      #if ENABLED(HAL_CAN_SET_PWM_FREQ) && defined(SPINDLE_LASER_FREQUENCY)
       EDIT_ITEM_FAST(CUTTER_MENU_FREQUENCY_TYPE, MSG_CUTTER_FREQUENCY, &cutter.frequency, 2000, 50000, cutter.refresh_frequency);
     #endif
-    #endif
     END_MENU();
   }