tinySA/os/hal/platforms/STM32F37x/adc_lld.c

/*
    ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
                 2011,2012,2013 Giovanni Di Sirio.

    This file is part of ChibiOS/RT.

    ChibiOS/RT 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.

    ChibiOS/RT 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 <http://www.gnu.org/licenses/>.
*/

/**
 * @file    STM32F4xx/adc_lld.c
 * @brief   STM32F4xx/STM32F2xx ADC subsystem low level driver source.
 *
 * @addtogroup ADC
 * @{
 */

#include "ch.h"
#include "hal.h"

#if HAL_USE_ADC || defined(__DOXYGEN__)

int debugzero = 0;

/*===========================================================================*/
/* Driver local definitions.                                                 */
/*===========================================================================*/

#define SDADC_FORBIDDEN_CR1_FLAGS   (SDADC_CR1_INIT   | SDADC_CR1_RDMAEN |  \
                                     SDADC_CR1_RSYNC  | SDADC_CR1_JSYNC  |  \
                                     SDADC_CR1_ROVRIE | SDADC_CR1_REOCIE |  \
                                     SDADC_CR1_JEOCIE | SDADC_CR1_EOCALIE)

#define SDADC_ENFORCED_CR1_FLAGS    (SDADC_CR1_JDMAEN  | SDADC_CR1_JOVRIE)

#define SDADC_FORBIDDEN_CR2_FLAGS   (SDADC_CR2_RSWSTART   |                 \
                                     SDADC_CR2_RCONT      |                 \
                                     SDADC_CR2_RCH        |                 \
                                     SDADC_CR2_JSWSTART   |                 \
                                     SDADC_CR2_JCONT      |                 \
                                     SDADC_CR2_STARTCALIB |                 \
                                     SDADC_CR2_CALIBCNT)

/*===========================================================================*/
/* Driver exported variables.                                                */
/*===========================================================================*/

/** @brief ADC1 driver identifier.*/
#if STM32_ADC_USE_ADC1 || defined(__DOXYGEN__)
ADCDriver ADCD1;
#endif

/** @brief ADC2 driver identifier.*/
#if STM32_ADC_USE_ADC2 || defined(__DOXYGEN__)
ADCDriver ADCD2;
#endif

/** @brief ADC3 driver identifier.*/
#if STM32_ADC_USE_ADC3 || defined(__DOXYGEN__)
ADCDriver ADCD3;
#endif

/** @brief SDADC1 driver identifier.*/
#if STM32_ADC_USE_SDADC1 || defined(__DOXYGEN__)
ADCDriver SDADCD1;
#endif

/** @brief SDADC2 driver identifier.*/
#if STM32_ADC_USE_SDADC2 || defined(__DOXYGEN__)
ADCDriver SDADCD2;
#endif

/** @brief SDADC3 driver identifier.*/
#if STM32_ADC_USE_SDADC3 || defined(__DOXYGEN__)
ADCDriver SDADCD3;
#endif

/*===========================================================================*/
/* Driver local variables and types.                                         */
/*===========================================================================*/

/*===========================================================================*/
/* Driver local functions.                                                   */
/*===========================================================================*/

/**
 * @brief   ADC DMA ISR service routine.
 *
 * @param[in] adcp      pointer to the @p ADCDriver object
 * @param[in] flags     pre-shifted content of the ISR register
 *
 * @notapi
 */
static void adc_lld_serve_dma_interrupt(ADCDriver *adcp, uint32_t flags) {
  /* DMA errors handling.*/
  if ((flags & (STM32_DMA_ISR_TEIF | STM32_DMA_ISR_DMEIF)) != 0) {
    /* DMA, this could help only if the DMA tries to access an unmapped
       address space or violates alignment rules.*/
    _adc_isr_error_code(adcp, ADC_ERR_DMAFAILURE);
  }
  else {
    /* It is possible that the conversion group has already be reset by the
       ADC error handler, in this case this interrupt is spurious.*/
    if (adcp->grpp != NULL) {
      if ((flags & STM32_DMA_ISR_HTIF) != 0) {
        /* Half transfer processing.*/
        _adc_isr_half_code(adcp);
      }
      if ((flags & STM32_DMA_ISR_TCIF) != 0) {
        /* Transfer complete processing.*/
        _adc_isr_full_code(adcp);
      }
    }
  }
}

#if STM32_ADC_USE_ADC
/**
 * @brief   ADC ISR service routine.
 *
 * @param[in] adcp      pointer to the @p ADCDriver object
 * @param[in] sr        content of the ISR register
 */
static void adc_lld_serve_interrupt(ADCDriver *adcp, uint32_t sr) {

  /* It could be a spurious interrupt caused by overflows after DMA disabling,
     just ignore it in this case.*/
  if (adcp->grpp != NULL) {
    if (sr & ADC_SR_AWD) {
      /* Analog watchdog error.*/
      _adc_isr_error_code(adcp, ADC_ERR_AWD1);
    }
  }
}
#endif /* STM32_ADC_USE_ADC */

#if STM32_ADC_USE_SDADC
/**
 * @brief   ADC ISR service routine.
 *
 * @param[in] adcp      pointer to the @p ADCDriver object
 * @param[in] isr       content of the ISR register
 */
static void sdadc_lld_serve_interrupt(ADCDriver *adcp, uint32_t isr) {

  /* It could be a spurious interrupt caused by overflows after DMA disabling,
     just ignore it in this case.*/
  if (adcp->grpp != NULL) {
    /* Note, an overflow may occur after the conversion ended before the driver
       is able to stop the ADC, this is why the DMA channel is checked too.*/
    if ((isr & SDADC_ISR_JOVRF) &&
        (dmaStreamGetTransactionSize(adcp->dmastp) > 0)) {
      /* ADC overflow condition, this could happen only if the DMA is unable
         to read data fast enough.*/
      _adc_isr_error_code(adcp, ADC_ERR_OVERFLOW);
    }
  }
}
#endif /* STM32_ADC_USE_SDADC */

/*===========================================================================*/
/* Driver interrupt handlers.                                                */
/*===========================================================================*/

#if STM32_ADC_USE_ADC1 || defined(__DOXYGEN__)
/**
 * @brief   ADC1 interrupt handler.
 *
 * @isr
 */
CH_IRQ_HANDLER(Vector88) {
  uint32_t sr;

  CH_IRQ_PROLOGUE();

  sr  = ADC1->SR;
  ADC1->SR = 0;
  adc_lld_serve_interrupt(&ADCD1, sr);

  CH_IRQ_EPILOGUE();
}
#endif /* STM32_ADC_USE_ADC1 */

#if STM32_ADC_USE_SDADC1 || defined(__DOXYGEN__)
/**
 * @brief   SDADC1 interrupt handler.
 *
 * @isr
 */
CH_IRQ_HANDLER(Vector134) {
  uint32_t isr;

  CH_IRQ_PROLOGUE();

  isr  = SDADC1->ISR;
  SDADC1->CLRISR = isr;
  sdadc_lld_serve_interrupt(&SDADCD1, isr);

  CH_IRQ_EPILOGUE();
}
#endif /* STM32_ADC_USE_SDADC1 */

#if STM32_ADC_USE_SDADC2 || defined(__DOXYGEN__)
/**
 * @brief   SDADC2 interrupt handler.
 *
 * @isr
 */
CH_IRQ_HANDLER(Vector138) {
  uint32_t isr;

  CH_IRQ_PROLOGUE();

  isr  = SDADC2->ISR;
  SDADC2->CLRISR = isr;
  sdadc_lld_serve_interrupt(&SDADCD2, isr);

  CH_IRQ_EPILOGUE();
}
#endif /* STM32_ADC_USE_SDADC2 */

#if STM32_ADC_USE_SDADC3 || defined(__DOXYGEN__)
/**
 * @brief   SDADC3 interrupt handler.
 *
 * @isr
 */
CH_IRQ_HANDLER(Vector13C) {
  uint32_t isr;

  CH_IRQ_PROLOGUE();

  isr  = SDADC3->ISR;
  SDADC3->CLRISR = isr;
  sdadc_lld_serve_interrupt(&SDADCD3, isr);

  CH_IRQ_EPILOGUE();
}
#endif /* STM32_ADC_USE_SDADC3 */

/*===========================================================================*/
/* Driver exported functions.                                                */
/*===========================================================================*/

/**
 * @brief   Low level ADC driver initialization.
 *
 * @notapi
 */
void adc_lld_init(void) {

#if STM32_ADC_USE_ADC1
  /* Driver initialization.*/
  adcObjectInit(&ADCD1);
  ADCD1.adc     = ADC1;
#if STM32_ADC_USE_SDADC
  ADCD1.sdadc   = NULL;
#endif
  ADCD1.dmastp  = STM32_DMA1_STREAM1;
  ADCD1.dmamode = STM32_DMA_CR_CHSEL(ADC1_DMA_CHANNEL) |
                  STM32_DMA_CR_PL(STM32_ADC_ADC1_DMA_PRIORITY) |
                  STM32_DMA_CR_DIR_P2M |
                  STM32_DMA_CR_MSIZE_HWORD | STM32_DMA_CR_PSIZE_HWORD |
                  STM32_DMA_CR_MINC        | STM32_DMA_CR_TCIE        |
                  STM32_DMA_CR_DMEIE       | STM32_DMA_CR_TEIE;
  nvicEnableVector(ADC1_IRQn, CORTEX_PRIORITY_MASK(STM32_ADC_IRQ_PRIORITY));
#endif

#if STM32_ADC_USE_SDADC1
  /* Driver initialization.*/
  adcObjectInit(&SDADCD1);
#if STM32_ADC_USE_ADC
  SDADCD1.adc     = NULL;
#endif
  SDADCD1.sdadc   = SDADC1;
  SDADCD1.dmastp  = STM32_DMA2_STREAM3;
  SDADCD1.dmamode = STM32_DMA_CR_CHSEL(SDADC1_DMA_CHANNEL) |
                  STM32_DMA_CR_PL(STM32_ADC_SDADC1_DMA_PRIORITY) |
                  STM32_DMA_CR_DIR_P2M |
                  STM32_DMA_CR_MSIZE_HWORD | STM32_DMA_CR_PSIZE_HWORD |
                  STM32_DMA_CR_MINC        | STM32_DMA_CR_TCIE        |
                  STM32_DMA_CR_DMEIE       | STM32_DMA_CR_TEIE;
  nvicEnableVector(SDADC1_IRQn,
                   CORTEX_PRIORITY_MASK(STM32_ADC_SDADC1_IRQ_PRIORITY));
#endif

#if STM32_ADC_USE_SDADC2
  /* Driver initialization.*/
  adcObjectInit(&SDADCD2);
#if STM32_ADC_USE_ADC
  SDADCD2.adc     = NULL;
#endif
  SDADCD2.sdadc   = SDADC2;
  SDADCD2.dmastp  = STM32_DMA2_STREAM4;
  SDADCD2.dmamode = STM32_DMA_CR_CHSEL(SDADC2_DMA_CHANNEL) |
                  STM32_DMA_CR_PL(STM32_ADC_SDADC2_DMA_PRIORITY) |
                  STM32_DMA_CR_DIR_P2M |
                  STM32_DMA_CR_MSIZE_HWORD | STM32_DMA_CR_PSIZE_HWORD |
                  STM32_DMA_CR_MINC        | STM32_DMA_CR_TCIE        |
                  STM32_DMA_CR_DMEIE       | STM32_DMA_CR_TEIE;
  nvicEnableVector(SDADC2_IRQn,
                   CORTEX_PRIORITY_MASK(STM32_ADC_SDADC2_IRQ_PRIORITY));
#endif

#if STM32_ADC_USE_SDADC3
  /* Driver initialization.*/
  adcObjectInit(&SDADCD3);
#if STM32_ADC_USE_ADC
  SDADCD3.adc     = NULL;
#endif
  SDADCD3.sdadc   = SDADC3;
  SDADCD3.dmastp  = STM32_DMA2_STREAM5;
  SDADCD3.dmamode = STM32_DMA_CR_CHSEL(SDADC3_DMA_CHANNEL) |
                  STM32_DMA_CR_PL(STM32_ADC_SDADC3_DMA_PRIORITY) |
                  STM32_DMA_CR_DIR_P2M |
                  STM32_DMA_CR_MSIZE_HWORD | STM32_DMA_CR_PSIZE_HWORD |
                  STM32_DMA_CR_MINC        | STM32_DMA_CR_TCIE        |
                  STM32_DMA_CR_DMEIE       | STM32_DMA_CR_TEIE;
  nvicEnableVector(SDADC3_IRQn,
                   CORTEX_PRIORITY_MASK(STM32_ADC_SDADC3_IRQ_PRIORITY));
#endif
}

/**
 * @brief   Configures and activates the ADC peripheral.
 *
 * @param[in] adcp      pointer to the @p ADCDriver object
 *
 * @notapi
 */
void adc_lld_start(ADCDriver *adcp) {

  /* If in stopped state then enables the ADC and DMA clocks.*/
  if (adcp->state == ADC_STOP) {
#if STM32_ADC_USE_ADC1
    if (&ADCD1 == adcp) {
      bool_t b;
      b = dmaStreamAllocate(adcp->dmastp,
                            STM32_ADC_ADC1_DMA_IRQ_PRIORITY,
                            (stm32_dmaisr_t)adc_lld_serve_dma_interrupt,
                            (void *)adcp);
      chDbgAssert(!b, "adc_lld_start(), #1", "stream already allocated");
      dmaStreamSetPeripheral(adcp->dmastp, &ADC1->DR);
      rccEnableADC1(FALSE);

      /* ADC initial setup, starting the analog part here in order to reduce
	     the latency when starting a conversion.*/
      adcp->adc->CR1 = 0;
      adcp->adc->CR2 = 0;
      adcp->adc->CR2 = ADC_CR2_ADON;
    }
#endif /* STM32_ADC_USE_ADC1 */

#if STM32_ADC_USE_SDADC1
    if (&SDADCD1 == adcp) {
      bool_t b = dmaStreamAllocate(adcp->dmastp,
                                   STM32_ADC_SDADC1_DMA_IRQ_PRIORITY,
                                   (stm32_dmaisr_t)adc_lld_serve_dma_interrupt,
                                   (void *)adcp);
      chDbgAssert(!b, "adc_lld_start(), #2", "stream already allocated");
      dmaStreamSetPeripheral(adcp->dmastp, &SDADC1->JDATAR);
      rccEnableSDADC1(FALSE);
      PWR->CR |= PWR_CR_SDADC1EN;
      adcp->sdadc->CR2 = 0;
      adcp->sdadc->CR1 = (adcp->config->cr1 | SDADC_ENFORCED_CR1_FLAGS) &
                          ~SDADC_FORBIDDEN_CR1_FLAGS;
      adcp->sdadc->CR2 = SDADC_CR2_ADON;
    }
#endif /* STM32_ADC_USE_SDADC1 */

#if STM32_ADC_USE_SDADC2
    if (&SDADCD2 == adcp) {
      bool_t b = dmaStreamAllocate(adcp->dmastp,
                                   STM32_ADC_SDADC2_DMA_IRQ_PRIORITY,
                                   (stm32_dmaisr_t)adc_lld_serve_dma_interrupt,
                                   (void *)adcp);
      chDbgAssert(!b, "adc_lld_start(), #3", "stream already allocated");
      dmaStreamSetPeripheral(adcp->dmastp, &SDADC2->JDATAR);
      rccEnableSDADC1(FALSE);
      PWR->CR |= PWR_CR_SDADC2EN;
      adcp->sdadc->CR2 = 0;
      adcp->sdadc->CR1 = (adcp->config->cr1 | SDADC_ENFORCED_CR1_FLAGS) &
                          ~SDADC_FORBIDDEN_CR1_FLAGS;
      adcp->sdadc->CR2 = SDADC_CR2_ADON;
    }
#endif /* STM32_ADC_USE_SDADC2 */

#if STM32_ADC_USE_SDADC3
    if (&SDADCD3 == adcp) {
      bool_t b = dmaStreamAllocate(adcp->dmastp,
                                   STM32_ADC_SDADC3_DMA_IRQ_PRIORITY,
                                   (stm32_dmaisr_t)adc_lld_serve_dma_interrupt,
                                   (void *)adcp);
      chDbgAssert(!b, "adc_lld_start(), #4", "stream already allocated");
      dmaStreamSetPeripheral(adcp->dmastp, &SDADC3->JDATAR);
      rccEnableSDADC1(FALSE);
      PWR->CR |= PWR_CR_SDADC3EN;
      adcp->sdadc->CR2 = 0;
      adcp->sdadc->CR1 = (adcp->config->cr1 | SDADC_ENFORCED_CR1_FLAGS) &
                          ~SDADC_FORBIDDEN_CR1_FLAGS;
      adcp->sdadc->CR2 = SDADC_CR2_ADON;
    }
#endif /* STM32_ADC_USE_SDADC3 */
  }
}

/**
 * @brief   Deactivates the ADC peripheral.
 *
 * @param[in] adcp      pointer to the @p ADCDriver object
 *
 * @notapi
 */
void adc_lld_stop(ADCDriver *adcp) {

  /* If in ready state then disables the ADC clock.*/
  if (adcp->state == ADC_READY) {
    dmaStreamRelease(adcp->dmastp);

#if STM32_ADC_USE_ADC1
    if (&ADCD1 == adcp) {
      adcp->adc->CR1 = 0;
      adcp->adc->CR2 = 0;
      rccDisableADC1(FALSE);
    }
#endif

#if STM32_ADC_USE_SDADC1
    if (&SDADCD1 == adcp) {
      adcp->sdadc->CR1 = 0;
      adcp->sdadc->CR2 = 0;
      rccDisableSDADC1(FALSE);
      PWR->CR &= ~PWR_CR_SDADC1EN;
    }
#endif

#if STM32_ADC_USE_SDADC2
    if (&SDADCD2 == adcp) {
      adcp->sdadc->CR1 = 0;
      adcp->sdadc->CR2 = 0;
      rccDisableSDADC2(FALSE);
      PWR->CR &= ~PWR_CR_SDADC2EN;
    }
#endif

#if STM32_ADC_USE_SDADC3
    if (&SDADCD3 == adcp) {
      adcp->sdadc->CR1 = 0;
      adcp->sdadc->CR2 = 0;
      rccDisableSDADC3(FALSE);
      PWR->CR &= ~PWR_CR_SDADC3EN;
    }
#endif
  }
}

/**
 * @brief   Starts an ADC conversion.
 *
 * @param[in] adcp      pointer to the @p ADCDriver object
 *
 * @notapi
 */
void adc_lld_start_conversion(ADCDriver *adcp) {
  uint32_t mode;
  const ADCConversionGroup* grpp = adcp->grpp;

  /* DMA setup.*/
  mode = adcp->dmamode;
  if (grpp->circular) {
    mode |= STM32_DMA_CR_CIRC;
  }
  if (adcp->depth > 1) {
    /* If the buffer depth is greater than one then the half transfer interrupt
       interrupt is enabled in order to allows streaming processing.*/
    mode |= STM32_DMA_CR_HTIE;
  }
  dmaStreamSetMemory0(adcp->dmastp, adcp->samples);
  dmaStreamSetTransactionSize(adcp->dmastp,
			      (uint32_t)grpp->num_channels * 
			      (uint32_t)adcp->depth);
  dmaStreamSetMode(adcp->dmastp, mode);
  dmaStreamEnable(adcp->dmastp);

#if STM32_ADC_USE_ADC && STM32_ADC_USE_SDADC
  if (adcp->adc != NULL)
#endif /* STM32_ADC_USE_ADC && STM32_ADC_USE_SDADC */
#if STM32_ADC_USE_ADC
  {
    uint32_t cr2 = ADC_CR2_ADON;

    /* ADC setup.*/
    adcp->adc->SR    = 0;
    adcp->adc->LTR   = grpp->u.adc.htr;
    adcp->adc->HTR   = grpp->u.adc.htr;
    adcp->adc->SMPR1 = grpp->u.adc.smpr[0];
    adcp->adc->SMPR2 = grpp->u.adc.smpr[1];
    adcp->adc->SQR1  = grpp->u.adc.sqr[0] |
                        ADC_SQR1_NUM_CH(grpp->num_channels);
    adcp->adc->SQR2  = grpp->u.adc.sqr[1];
    adcp->adc->SQR3  = grpp->u.adc.sqr[2];

    /* ADC conversion start, the start is performed using the method
       specified in the CR2 configuration, usually ADC_CR2_SWSTART.*/
    adcp->adc->CR1   = grpp->u.adc.cr1 | ADC_CR1_AWDIE | ADC_CR1_SCAN;
    if ((grpp->u.adc.cr2 & ADC_CR2_SWSTART) != 0)
      cr2 |= ADC_CR2_CONT;
    adcp->adc->CR2 = grpp->u.adc.cr2 | cr2 | ADC_CR2_DMA | ADC_CR2_ADON;
  }
#endif /* STM32_ADC_USE_ADC */
#if STM32_ADC_USE_ADC && STM32_ADC_USE_SDADC
  else if (adcp->sdadc != NULL)
#endif /* STM32_ADC_USE_ADC && STM32_ADC_USE_SDADC */
#if STM32_ADC_USE_SDADC
  {
    uint32_t cr2 = SDADC_CR2_ADON;

    /* Entering initialization mode.*/
    adcp->sdadc->CR1 |= SDADC_CR1_INIT;
    while ((adcp->sdadc->ISR & SDADC_ISR_INITRDY) == 0)
      ;

    /* SDADC setup.*/
    adcp->sdadc->CONF0R   = grpp->u.sdadc.confxr[0];
    adcp->sdadc->CONF1R   = grpp->u.sdadc.confxr[1];
    adcp->sdadc->CONF2R   = grpp->u.sdadc.confxr[2];
    adcp->sdadc->CONFCHR1 = grpp->u.sdadc.confchr[0];
    adcp->sdadc->CONFCHR2 = grpp->u.sdadc.confchr[1];

    /* Leaving initialization mode.*/
    adcp->sdadc->CR1 &= ~SDADC_CR1_INIT;

    /* SDADC conversion start, the start is performed using the method
       specified in the CR2 configuration, usually SDADC_CR2_JSWSTART.*/
    if ((grpp->u.sdadc.cr2 & SDADC_CR2_JSWSTART) != 0)
      cr2 |= SDADC_CR2_JCONT;
    adcp->sdadc->CR2 = (grpp->u.sdadc.cr2 & ~SDADC_FORBIDDEN_CR2_FLAGS) | cr2;
  }
#endif /* STM32_ADC_USE_SDADC */
#if STM32_ADC_USE_ADC && STM32_ADC_USE_SDADC
  else {
    chDbgAssert(FALSE, "adc_lld_start_conversion(), #1", "invalid state");
  }
#endif /* STM32_ADC_USE_ADC && STM32_ADC_USE_SDADC */
}

/**
 * @brief   Stops an ongoing conversion.
 *
 * @param[in] adcp      pointer to the @p ADCDriver object
 *
 * @notapi
 */
void adc_lld_stop_conversion(ADCDriver *adcp) {

  /* Disabling the associated DMA stream.*/
  dmaStreamDisable(adcp->dmastp);

#if STM32_ADC_USE_ADC && STM32_ADC_USE_SDADC
  if (adcp->adc != NULL)
#endif /* STM32_ADC_USE_ADC && STM32_ADC_USE_SDADC */
#if STM32_ADC_USE_ADC
  {
    adcp->adc->CR1 = 0;
    adcp->adc->CR2 = 0;
    adcp->adc->CR2 = ADC_CR2_ADON;
  }
#endif /* STM32_ADC_USE_ADC */
#if STM32_ADC_USE_ADC && STM32_ADC_USE_SDADC
  else if (adcp->sdadc != NULL)
#endif /* STM32_ADC_USE_ADC && STM32_ADC_USE_SDADC */
#if STM32_ADC_USE_SDADC
  {
    adcp->sdadc->CR1 = 0;
    adcp->sdadc->CR2 = 0;
    adcp->sdadc->CR2 = ADC_CR2_ADON;
  }
#endif /* STM32_ADC_USE_SDADC */
#if STM32_ADC_USE_ADC && STM32_ADC_USE_SDADC
  else {
    chDbgAssert(FALSE, "adc_lld_stop_conversion(), #1", "invalid state");
  }
#endif /* STM32_ADC_USE_ADC && STM32_ADC_USE_SDADC */
}

/**
 * @brief   Calibrates an ADC unit.
 * @note    The calibration must be performed after calling @p adcStart().
 * @note    For SDADC units it is assumed that the field SDADC_CR2_CALIBCNT
 *          has been
 *
 * @param[in] adcp      pointer to the @p ADCDriver object
 *
 * @api
 */
void adcSTM32Calibrate(ADCDriver *adcp) {

  chDbgAssert((adcp->state == ADC_READY) ||
              (adcp->state == ADC_COMPLETE) ||
              (adcp->state == ADC_ERROR),
              "adcSTM32Calibrate(), #1", "not ready");

#if STM32_ADC_USE_ADC && STM32_ADC_USE_SDADC
  if (adcp->adc != NULL)
#endif /* STM32_ADC_USE_ADC && STM32_ADC_USE_SDADC */
#if STM32_ADC_USE_ADC
  {
    /* Resetting calibration just to be safe.*/
    ADC1->CR2 = ADC_CR2_ADON | ADC_CR2_RSTCAL;
    while ((ADC1->CR2 & ADC_CR2_RSTCAL) != 0)
      ;

    /* Calibration.*/
    ADC1->CR2 = ADC_CR2_ADON | ADC_CR2_CAL;
    while ((ADC1->CR2 & ADC_CR2_CAL) != 0)
      ;
  }
#endif /* STM32_ADC_USE_ADC */
#if STM32_ADC_USE_ADC && STM32_ADC_USE_SDADC
  else if (adcp->sdadc != NULL)
#endif /* STM32_ADC_USE_ADC && STM32_ADC_USE_SDADC */
#if STM32_ADC_USE_SDADC
  {
    /* Selecting a full calibration in three steps.*/
    adcp->sdadc->CR2  = (adcp->sdadc->CR2 & ~SDADC_CR2_CALIBCNT) |
                        SDADC_CR2_CALIBCNT_1;

    /* Calibration.*/
    adcp->sdadc->CR2 |= SDADC_CR2_STARTCALIB;
    while ((adcp->sdadc->ISR & SDADC_ISR_EOCALF) == 0)
      ;

    /* Clearing the EOCALF flag.*/
    adcp->sdadc->CLRISR |= SDADC_ISR_CLREOCALF;
  }
#endif /* STM32_ADC_USE_SDADC */
#if STM32_ADC_USE_ADC && STM32_ADC_USE_SDADC
  else {
    chDbgAssert(FALSE, "adcSTM32Calibrate(), #2", "invalid state");
  }
#endif /* STM32_ADC_USE_ADC && STM32_ADC_USE_SDADC */
}

#if STM32_ADC_USE_ADC || defined(__DOXYGEN__)
/**
 * @brief   Enables the TSVREFE bit.
 * @details The TSVREFE bit is required in order to sample the internal
 *          temperature sensor and internal reference voltage.
 * @note    This is an STM32-only functionality.
 *
 * @api
 */
void adcSTM32EnableTSVREFE(void) {

  ADC1->CR2 |= ADC_CR2_TSVREFE;
}

/**
 * @brief   Disables the TSVREFE bit.
 * @details The TSVREFE bit is required in order to sample the internal
 *          temperature sensor and internal reference voltage.
 * @note    This is an STM32-only functionality.
 *
 * @api
 */
void adcSTM32DisableTSVREFE(void) {

  ADC1->CR2 &= ~ADC_CR2_TSVREFE;
}

/**
 * @brief   Enables the VBATE bit.
 * @details The VBATE bit is required in order to sample the VBAT channel.
 * @note    This is an STM32-only functionality.
 *
 * @api
 */
void adcSTM32EnableVBATE(void) {

  SYSCFG->CFGR1 |= SYSCFG_CFGR1_VBAT;
}

/**
 * @brief   Disables the VBATE bit.
 * @details The VBATE bit is required in order to sample the VBAT channel.
 * @note    This is an STM32-only functionality.
 *
 * @api
 */
void adcSTM32DisableVBATE(void) {

  SYSCFG->CFGR1 &= ~SYSCFG_CFGR1_VBAT;
}
#endif /* STM32_ADC_USE_ADC */

#if 0 || defined(__DOXYGEN__)
/**
  * @brief  Configures the calibration sequence.
  * @note   TODO - UPDATE
  * @param  ADCDriver*  one of &SDADCD1, &SDADCD2, &SDADCD3
  * @param  SDADC_CalibrationSequence: Number of calibration sequence to be performed.
  *          This parameter can be one of the following values:
  *            @arg SDADC_CalibrationSequence_1: One calibration sequence will be performed
  *                                      to calculate OFFSET0[11:0] (offset that corresponds to conf0)
  *            @arg SDADC_CalibrationSequence_2: Two calibration sequences will be performed
  *                                      to calculate OFFSET0[11:0] and OFFSET1[11:0]
  *                                      (offsets that correspond to conf0 and conf1)
  *            @arg SDADC_CalibrationSequence_3: Three calibration sequences will be performed
  *                                      to calculate OFFSET0[11:0], OFFSET1[11:0], 
  *                                      and OFFSET2[11:0] (offsets that correspond to conf0, conf1 and conf2)
  * @retval None
  */
void sdadcSTM32Calibrate(ADCDriver* adcp,
			 SDADC_NUM_CALIB_SEQ numCalibSequences,
			 ADCConversionGroup* grpp)
{
  uint32_t SDADCTimeout = 0;
  uint32_t tmpcr2 = 0;

  if (!(adcp == &SDADCD1 ||
	adcp == &SDADCD2 ||
	adcp == &SDADCD3))
      return;

  sdadcSTM32SetInitializationMode(adcp, true);

  /* SDADC setup.*/
  adcp->sdadc->CR2      = grpp->ll.sdadc.cr2;
  adcp->sdadc->CONF0R   = grpp->ll.sdadc.conf0r;
  adcp->sdadc->CONF1R   = grpp->ll.sdadc.conf1r;
  adcp->sdadc->CONF2R   = grpp->ll.sdadc.conf2r;
  adcp->sdadc->CONFCHR1 = grpp->ll.sdadc.confchr1;
  adcp->sdadc->CONFCHR2 = grpp->ll.sdadc.confchr2;

  sdadcSTM32SetInitializationMode(adcp, false);

  /* configure calibration to be performed on conf0 */
  /* Get SDADC_CR2 register value */
  tmpcr2 = adcp->sdadc->CR2;

  /* Clear the SDADC_CR2_CALIBCNT bits */
  tmpcr2 &= (uint32_t) (~SDADC_CR2_CALIBCNT);
  /* Set the calibration sequence */
  tmpcr2 |= numCalibSequences;

  /* 
     Write in SDADC_CR2 and
     start calibration 
  */
  adcp->sdadc->CR2 = tmpcr2 | SDADC_CR2_STARTCALIB;
 
  /* Set calibration timeout: 5.12 ms at 6 MHz in a single calibration sequence */
  SDADCTimeout = SDADC_CAL_TIMEOUT;

  /* wait for SDADC Calibration process to end */
  while (((adcp->sdadc->ISR & SDADC_ISR_EOCALF) == 0) && (--SDADCTimeout != 0));

  if(SDADCTimeout == 0)
  {
    /* Calib timeout */
    port_halt();
    return;
  }

  /* cleanup by clearing EOCALF flag */
  adcp->sdadc->CLRISR |= SDADC_ISR_CLREOCALF;
}
#endif /* STM32_ADC_USE_SDADC */

#endif /* HAL_USE_ADC */

/** @} */