STM32 Timer with HAL

[rm5248]

I'm trying to use the input compare of a timer with Zephyr. I have a prototype that works with with STM32CubeIDE and the standard STM32 HAL library, but I'm unable to port it to Zephyr. It seems that I do not get an interrupt from the timer when the pin value changes, although it is setup properly as far as I can tell.

Here's a simplified version of my code, which uses the HAL code to do the initialization of the timer and tries to set it running:

TIM_HandleTypeDef htim2;

void tim2_irq_fn(TIM_HandleTypeDef *htim)
{
	if (htim->Channel == HAL_TIM_ACTIVE_CHANNEL_1)
	{
		HAL_TIM_ReadCapturedValue(htim, TIM_CHANNEL_1);
		__HAL_TIM_SET_COUNTER(htim, 0);
		printf("-");
	}else{
		printf("*");
	}
}

void HAL_TIM_IC_CaptureCallback(TIM_HandleTypeDef *htim){
	tim2_irq_fn(htim);
}

static int MX_TIM2_Init(void)
{
  /* USER CODE BEGIN TIM2_Init 0 */

  /* USER CODE END TIM2_Init 0 */

  TIM_ClockConfigTypeDef sClockSourceConfig = {0};
  TIM_MasterConfigTypeDef sMasterConfig = {0};
  TIM_IC_InitTypeDef sConfigIC = {0};

  /* USER CODE BEGIN TIM2_Init 1 */

  /* USER CODE END TIM2_Init 1 */
  htim2.Instance = TIM2;
  htim2.Init.Prescaler = 32;
  htim2.Init.CounterMode = TIM_COUNTERMODE_UP;
  htim2.Init.Period = 4294967295;
  htim2.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
  htim2.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;
  if (HAL_TIM_Base_Init(&htim2) != HAL_OK)
  {
//    Error_Handler();
	  return 1;
  }
  sClockSourceConfig.ClockSource = TIM_CLOCKSOURCE_INTERNAL;
  if (HAL_TIM_ConfigClockSource(&htim2, &sClockSourceConfig) != HAL_OK)
  {
//    Error_Handler();
	  return 2;
  }
  if (HAL_TIM_IC_Init(&htim2) != HAL_OK)
  {
//    Error_Handler();
	  return 3;
  }
  sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET;
  sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
  if (HAL_TIMEx_MasterConfigSynchronization(&htim2, &sMasterConfig) != HAL_OK)
  {
//    Error_Handler();
	  return 4;
  }
  sConfigIC.ICPolarity = TIM_INPUTCHANNELPOLARITY_BOTHEDGE;
  sConfigIC.ICSelection = TIM_ICSELECTION_DIRECTTI;
  sConfigIC.ICPrescaler = TIM_ICPSC_DIV1;
  sConfigIC.ICFilter = 0;
  if (HAL_TIM_IC_ConfigChannel(&htim2, &sConfigIC, TIM_CHANNEL_1) != HAL_OK)
  {
//    Error_Handler();
	  return 5;
  }
  /* USER CODE BEGIN TIM2_Init 2 */

  /* USER CODE END TIM2_Init 2 */
  return 0;

}

void init_function(){
	// Configure the pinctrl for the timer
	GPIO_InitTypeDef GPIO_InitStruct = {0};
	GPIO_InitStruct.Pin = GPIO_PIN_15;
	GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
	GPIO_InitStruct.Pull = GPIO_NOPULL;
	GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
	GPIO_InitStruct.Alternate = GPIO_AF2_TIM2;
	HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

	IRQ_CONNECT(TIM2_IRQn, 0, tim2_irq_fn, &htim2, 0);
	irq_enable(TIM2_IRQn);

	int res = MX_TIM2_Init();
	if(res != 0){
		printf("can't init: %d\n", res);
	}

	// Start the timer
	if(HAL_TIM_IC_Start_IT(&htim2, TIM_CHANNEL_1) != HAL_OK){
		printf("can't start timer\n");
	}
}

I've been assuming that I need to do the IRQ_CONNECT in order to properly install my IRQ handler, but it's not working at all(the interrupt is never called). Is there something else that I need to do in order to make sure that the HAL code is playing nicely with Zephyr?

[FRASTM]

Not sure this is the best approach to go with HAL stm32 functions, LL driver is preferable.
On the other hand, there is already capture in the pwm driver (see CONFIG_PWM_CAPTURE), can that help you ?

[rm5248]

Looking at it more, I think my problem before was that the clocks to the peripheral were not turned on. On the STM32, register access to a peripheral is not available unless the clock has been turned on.

Using a combination of LL methods and direct register access I was able to get my code working properly after enabling the clocks to the timer peripheral.