nuttx/configs/nucleo-144/src/stm32_adc.c

/************************************************************************************
 * configs/nucleo-144/src/stm32_adc.c
 *
 *   Copyright (C) 2016 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <gnutt@nuttx.org>
 *
 * 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 NuttX 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 OWNER 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.
 *
 ************************************************************************************/

/************************************************************************************
 * Included Files
 ************************************************************************************/

#include <nuttx/config.h>

#include <errno.h>
#include <debug.h>

#include <nuttx/board.h>
#include <nuttx/analog/adc.h>
#include <arch/board/board.h>

#include "chip.h"
#include "stm32_gpio.h"
#include "stm32_adc.h"
#include "nucleo-144.h"

#ifdef CONFIG_ADC

/************************************************************************************
 * Pre-processor Definitions
 ************************************************************************************/

/* Configuration ********************************************************************/
/* Up to 3 ADC interfaces are supported */

#if STM32F7_NADC < 3
#  undef CONFIG_STM32F7_ADC3
#endif

#if STM32F7_NADC < 2
#  undef CONFIG_STM32F7_ADC2
#endif

#if STM32F7_NADC < 1
#  undef CONFIG_STM32F7_ADC1
#endif

#if defined(CONFIG_STM32F7_ADC1) || defined(CONFIG_STM32F7_ADC2) || defined(CONFIG_STM32F7_ADC3)
#ifndef CONFIG_STM32F7_ADC1
#  warning "Channel information only available for ADC1"
#endif

/* The number of ADC channels in the conversion list */

#define ADC1_NCHANNELS 1

/************************************************************************************
 * Private Data
 ************************************************************************************/

/* Identifying number of each ADC channel: Variable Resistor.
 *
 * {1,  2,  3, 4,  5,  6, 7,  8,  9, 10, 11, 12, 13, 15};
 */

#ifdef CONFIG_STM32F7_ADC1
static const uint8_t  g_chanlist[ADC1_NCHANNELS] = {3};

/* Configurations of pins used byte each ADC channels
 *
 * {GPIO_ADC1_IN1,  GPIO_ADC1_IN2,  GPIO_ADC1_IN3, GPIO_ADC1_IN4,  GPIO_ADC1_IN5, 
 *  GPIO_ADC1_IN6,  GPIO_ADC1_IN7,  GPIO_ADC1_IN8,  GPIO_ADC1_IN9, GPIO_ADC1_IN10,
 *  GPIO_ADC1_IN11, GPIO_ADC1_IN12, GPIO_ADC1_IN13, GPIO_ADC1_IN15};
 */

static const uint32_t g_pinlist[ADC1_NCHANNELS] = {GPIO_ADC1_IN3};
#endif

/************************************************************************************
 * Private Functions
 ************************************************************************************/

/************************************************************************************
 * Public Functions
 ************************************************************************************/

/************************************************************************************
 * Name: board_adc_setup
 *
 * Description:
 *   All STM32 architectures must provide the following interface to work with
 *   examples/adc.
 *
 ************************************************************************************/

int board_adc_setup(void)
{
  return board_adc_initialize();
}

/************************************************************************************
 * Name: stm32_adc_initialize
 *
 * Description:
 *   Called at application startup time to initialize the ADC functionality.
 *
 ************************************************************************************/

int board_adc_initialize(void)
{
#ifdef CONFIG_STM32F7_ADC1
  static bool initialized = false;
  struct adc_dev_s *adc;
  int ret;
  int i;

  /* Check if we have already initialized */

  if (!initialized)
    {
      /* Configure the pins as analog inputs for the selected channels */

      for (i = 0; i < ADC1_NCHANNELS; i++)
        {
          if (g_pinlist[i] != 0)
            {
              stm32_configgpio(g_pinlist[i]);
            }
        }

      /* Call stm32_adcinitialize() to get an instance of the ADC interface */

      adc = stm32_adc_initialize(1, g_chanlist, ADC1_NCHANNELS);
      if (adc == NULL)
        {
          aerr("ERROR: Failed to get ADC interface\n");
          return -ENODEV;
        }

      /* Register the ADC driver at "/dev/adc0" */

      ret = adc_register("/dev/adc0", adc);
      if (ret < 0)
        {
          aerr("ERROR: adc_register failed: %d\n", ret);
          return ret;
        }

      /* Now we are initialized */

      initialized = true;
    }

  return OK;
#else
  return -ENOSYS;
#endif
}

#endif /* CONFIG_STM32F7_ADC1 || CONFIG_STM32F7_ADC2 || CONFIG_STM32F7_ADC3 */
#endif /* CONFIG_ADC */