/*****************************************************************************
 *
 * \file
 *
 * \brief ADC driver for AVR UC3.
 *
 * This file defines a useful set of functions for ADC on AVR UC3 devices.
 *
 * Copyright (c) 2009 Atmel Corporation. All rights reserved.
 *
 * \asf_license_start
 *
 * 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. The name of Atmel may not be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * 4. This software may only be redistributed and used in connection with an
 *    Atmel microcontroller product.
 *
 * THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
 * EXPRESSLY AND SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL 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.
 *
 * \asf_license_stop
 *
 *****************************************************************************/


#include <avr32/io.h>
#include "compiler.h"
#include "adc.h"


void adc_configure(volatile avr32_adc_t * adc)
{
  Assert( adc!=NULL );

#ifdef USE_ADC_8_BITS
  adc->mr |= 1<<AVR32_ADC_LOWRES_OFFSET;
#endif
  // set Sample/Hold time to max so that the ADC capacitor should be loaded entirely
  adc->mr |= 0xF << AVR32_ADC_SHTIM_OFFSET;
  // set Startup to max so that the ADC capacitor should be loaded entirely
  adc->mr |= 0x1F << AVR32_ADC_STARTUP_OFFSET;
}

void adc_start(volatile avr32_adc_t * adc)
{
  Assert( adc!=NULL );

  // start conversion
  adc->cr = AVR32_ADC_START_MASK;
}

void adc_enable(volatile avr32_adc_t * adc, unsigned short channel)
{
  Assert( adc!=NULL );
  Assert( channel <= AVR32_ADC_CHANNELS_MSB );  // check if channel exist

  // enable channel
  adc->cher = (1 << channel);
}

void adc_disable(volatile avr32_adc_t * adc, unsigned short channel)
{
  Assert( adc!=NULL );
  Assert( channel <= AVR32_ADC_CHANNELS_MSB ); // check if channel exist

  if (adc_get_status(adc, channel) == true)
  {
    // disable channel
    adc->chdr |= (1 << channel);
  }
}

bool adc_get_status(volatile avr32_adc_t * adc, unsigned short channel)
{
  Assert( adc!=NULL );
  Assert( channel <= AVR32_ADC_CHANNELS_MSB );  // check if channel exist

  return ((adc->chsr & (1 << channel)) ? true : false);
}

bool adc_check_eoc(volatile avr32_adc_t * adc, unsigned short channel)
{
  Assert( adc!=NULL );
  Assert( channel <= AVR32_ADC_CHANNELS_MSB );  // check if channel exist

  // get SR register : EOC bit for channel
  return ((adc->sr & (1 << channel)) ? true : false);
}

bool adc_check_ovr(volatile avr32_adc_t * adc, unsigned short channel)
{
  Assert( adc!=NULL );
  Assert( channel <= AVR32_ADC_CHANNELS_MSB );  // check if channel exist

  // get SR register : OVR bit for channel
  return ((adc->sr & (1 << (channel + 8))) ? FAIL : PASS);
}

unsigned long adc_get_value(volatile avr32_adc_t * adc, unsigned short channel)
{
  Assert( adc!=NULL );
  Assert( channel <= AVR32_ADC_CHANNELS_MSB );  // check if channel exist

  // wait for end of conversion
  while(adc_check_eoc(adc, channel) != true);
  return *((unsigned long * )((&(adc->cdr0)) + channel));
}


unsigned long adc_get_latest_value(volatile avr32_adc_t * adc)
{
  Assert( adc!=NULL );

  // Wait for the data ready flag
  while((adc->sr & AVR32_ADC_DRDY_MASK) != AVR32_ADC_DRDY_MASK);
  return adc->lcdr;
}

