text: /****************************************************************************
   * boards/arm/imxrt/imxrt1064-evk/src/imxrt_adc.c
   *
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.  The
   * ASF licenses this file to you under the Apache License, Version 2.0 (the
   * "License"); you may not use this file except in compliance with the
   * License.  You may obtain a copy of the License at
   *
   *   http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
   * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
   * License for the specific language governing permissions and limitations
   * under the License.
   *
   ****************************************************************************/
  
  /****************************************************************************
   * 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 "arm_arch.h"
  
  #include "imxrt_adc.h"
  
  #ifdef CONFIG_IMXRT_ADC
  
  /****************************************************************************
   * Pre-processor Definitions
   ****************************************************************************/
  
  /* Configuration ************************************************************/
  
  #define ADC1_NCHANNELS 3
  #define ADC2_NCHANNELS 3
  
  /****************************************************************************
   * Private Data
   ****************************************************************************/
  
  static const uint8_t g_chanlist1[ADC1_NCHANNELS] =
    {
      /* Arduino Interface pins A0 to A2 */
  
      15,
      0,
      9,
    };
  
  static const uint8_t g_chanlist2[ADC2_NCHANNELS] =
    {
      /* Arduino Interface pins A3 to A5 */
  
      10,
      6,
      5
    };
  
  /****************************************************************************
   * Public Functions
   ****************************************************************************/
  
  /****************************************************************************
   * Name: imxrt_adc_setup
   *
   * Description:
   *   Initialize ADC and register the ADC driver.
   *
   ****************************************************************************/
  
  int imxrt_adc_initialize(void)
  {
    static bool initialized = false;
    struct adc_dev_s *adc;
    int ret;
  
    /* Check if we have already initialized */
  
    if (!initialized)
      {
        /* Call imxrt_adcinitialize() to get an instance of the ADC interface */
  
  #ifdef CONFIG_IMXRT_ADC1
        adc = imxrt_adcinitialize(1, g_chanlist1, ADC1_NCHANNELS);
        if (adc == NULL)
          {
            aerr("ERROR: Failed to get ADC interface for ADC1\n");
            return -ENODEV;
          }
  
        /* Register the ADC driver at "/dev/adc1" */
  
        ret = adc_register("/dev/adc1", adc);
        if (ret < 0)
          {
            aerr("ERROR: adc_register adc1 failed: %d\n", ret);
            return ret;
          }
  #endif
  
  #ifdef CONFIG_IMXRT_ADC2
        adc = imxrt_adcinitialize(2, g_chanlist2, ADC2_NCHANNELS);
        if (adc == NULL)
          {
            aerr("ERROR: Failed to get ADC interface for ADC2\n");
            return -ENODEV;
          }
  
        /* Register the ADC driver at "/dev/adc2" */
  
        ret = adc_register("/dev/adc2", adc);
        if (ret < 0)
          {
            aerr("ERROR: adc_register adc2 failed: %d\n", ret);
            return ret;
          }
  #endif
  
        /* Now we are initialized */
  
        initialized = true;
      }
  
    return OK;
  }
  
  #endif /* CONFIG_ADC */
  