text: /* mbed Microcontroller Library
   *******************************************************************************
   * Copyright (c) 2014, STMicroelectronics
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions are met:
   *
   * 1. Redistributions of source code must retain the above copyright notice,
   *    this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright notice,
   *    this list of conditions and the following disclaimer in the documentation
   *    and/or other materials provided with the distribution.
   * 3. Neither the name of STMicroelectronics nor the names of its contributors
   *    may be used to endorse or promote products derived from this software
   *    without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
   * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
   * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
   * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
   * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   *******************************************************************************
   */
  #include "pwmout_api.h"
  
  #if DEVICE_PWMOUT
  
  #include "cmsis.h"
  #include "pinmap.h"
  #include "mbed_error.h"
  #include "PeripheralPins.h"
  
  static TIM_HandleTypeDef TimHandle;
  
  void pwmout_init(pwmout_t* obj, PinName pin)
  {
      // Get the peripheral name from the pin and assign it to the object
      obj->pwm = (PWMName)pinmap_peripheral(pin, PinMap_PWM);
  
      if (obj->pwm == (PWMName)NC) {
          error("PWM error: pinout mapping failed.");
      }
  
      // Enable TIM clock
      if (obj->pwm == PWM_1) __TIM1_CLK_ENABLE();
      if (obj->pwm == PWM_2) __TIM2_CLK_ENABLE();
      if (obj->pwm == PWM_3) __TIM3_CLK_ENABLE();
      if (obj->pwm == PWM_8) __TIM8_CLK_ENABLE();
      if (obj->pwm == PWM_15) __TIM15_CLK_ENABLE();
      if (obj->pwm == PWM_16) __TIM16_CLK_ENABLE();
      if (obj->pwm == PWM_17) __TIM17_CLK_ENABLE();
  
      // Configure GPIO
      pinmap_pinout(pin, PinMap_PWM);
  
      obj->pin = pin;
      obj->period = 0;
      obj->pulse = 0;
  
      pwmout_period_us(obj, 20000); // 20 ms per default
  }
  
  void pwmout_free(pwmout_t* obj)
  {
      // Configure GPIO
      pin_function(obj->pin, STM_PIN_DATA(STM_MODE_INPUT, GPIO_NOPULL, 0));
  }
  
  void pwmout_write(pwmout_t* obj, float value)
  {
      TIM_OC_InitTypeDef sConfig;
      int channel = 0;
      int complementary_channel = 0;
  
      TimHandle.Instance = (TIM_TypeDef *)(obj->pwm);
  
      if (value < (float)0.0) {
          value = 0.0;
      } else if (value > (float)1.0) {
          value = 1.0;
      }
  
      obj->pulse = (uint32_t)((float)obj->period * value);
  
      // Configure channels
      sConfig.OCMode       = TIM_OCMODE_PWM1;
      sConfig.Pulse        = obj->pulse;
      sConfig.OCPolarity   = TIM_OCPOLARITY_HIGH;
      sConfig.OCNPolarity  = TIM_OCNPOLARITY_HIGH;
      sConfig.OCFastMode   = TIM_OCFAST_DISABLE;
      sConfig.OCIdleState  = TIM_OCIDLESTATE_RESET;
      sConfig.OCNIdleState = TIM_OCNIDLESTATE_RESET;
  
      switch (obj->pin) {
  
          // Channels 1
          case PA_2:
          case PA_6:
          case PA_7:
          case PA_8:
          case PA_12:
          case PA_15:
          case PB_4:
          case PB_5:
          case PB_8:
          case PB_9:
          case PB_14:
          case PC_0:
          case PC_6:
              channel = TIM_CHANNEL_1;
              break;
  
          // Channels 1N
          case PA_1:
          case PA_13:
          case PB_3:
          case PB_6:
          case PB_7:
          case PB_13:
          case PC_10:
          case PC_13:
              channel = TIM_CHANNEL_1;
              complementary_channel = 1;
              break;
  
          // Channels 2
          case PA_3:
          case PA_4:
          case PA_9:
          case PA_14:
          case PB_15:
          case PC_1:
          case PC_7:
              channel = TIM_CHANNEL_2;
              break;
  
          // Channels 2N
          case PB_0:
          case PC_11:
              channel = TIM_CHANNEL_2;
              complementary_channel = 1;
              break;
  
          // Channels 3
          case PA_10:
          case PC_2:
          case PC_8:
              channel = TIM_CHANNEL_3;
              break;
  
          // Channels 3N
          case PB_1:
          case PC_12:
          case PF_0:
              channel = TIM_CHANNEL_3;
              complementary_channel = 1;
              break;
  
          // Channels 4
          case PA_11:
          case PC_3:
          case PC_9:
              channel = TIM_CHANNEL_4;
              break;
  
          default:
              return;
      }
  
      HAL_TIM_PWM_ConfigChannel(&TimHandle, &sConfig, channel);
  
      if (complementary_channel) {
          HAL_TIMEx_PWMN_Start(&TimHandle, channel);
      } else {
          HAL_TIM_PWM_Start(&TimHandle, channel);
      }
  }
  
  float pwmout_read(pwmout_t* obj)
  {
      float value = 0;
      if (obj->period > 0) {
          value = (float)(obj->pulse) / (float)(obj->period);
      }
      return ((value > (float)1.0) ? (float)(1.0) : (value));
  }
  
  void pwmout_period(pwmout_t* obj, float seconds)
  {
      pwmout_period_us(obj, seconds * 1000000.0f);
  }
  
  void pwmout_period_ms(pwmout_t* obj, int ms)
  {
      pwmout_period_us(obj, ms * 1000);
  }
  
  void pwmout_period_us(pwmout_t* obj, int us)
  {
      TimHandle.Instance = (TIM_TypeDef *)(obj->pwm);
  
      float dc = pwmout_read(obj);
  
      __HAL_TIM_DISABLE(&TimHandle);
  
      // Update the SystemCoreClock variable
      SystemCoreClockUpdate();
  
      TimHandle.Init.Period        = us - 1;
      TimHandle.Init.Prescaler     = (uint16_t)(SystemCoreClock / 1000000) - 1; // 1 µs tick
      TimHandle.Init.ClockDivision = 0;
      TimHandle.Init.CounterMode   = TIM_COUNTERMODE_UP;
      HAL_TIM_PWM_Init(&TimHandle);
  
      // Set duty cycle again
      pwmout_write(obj, dc);
  
      // Save for future use
      obj->period = us;
  
      __HAL_TIM_ENABLE(&TimHandle);
  }
  
  void pwmout_pulsewidth(pwmout_t* obj, float seconds)
  {
      pwmout_pulsewidth_us(obj, seconds * 1000000.0f);
  }
  
  void pwmout_pulsewidth_ms(pwmout_t* obj, int ms)
  {
      pwmout_pulsewidth_us(obj, ms * 1000);
  }
  
  void pwmout_pulsewidth_us(pwmout_t* obj, int us)
  {
      float value = (float)us / (float)obj->period;
      pwmout_write(obj, value);
  }
  
  #endif
  