Arduino/hardware/arduino/sam/system/libsam/source/adc.c

/* ----------------------------------------------------------------------------
 *         SAM Software Package License
 * ----------------------------------------------------------------------------
 * Copyright (c) 2011-2012, Atmel Corporation
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following condition is met:
 *
 * - Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the disclaimer below.
 *
 * Atmel's name may not be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * DISCLAIMER: THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
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 */

#include "../chip.h"

/// @cond 0
/**INDENT-OFF**/
#ifdef __cplusplus
extern "C" {
#endif
/**INDENT-ON**/
/// @endcond

/**
 * \defgroup sam_drivers_adc_group Analog-to-digital Converter (ADC)
 *
 * Driver for the Analog-to-digital Converter. This driver provides access to the main
 * features of the ADC controller.
 *
 * @{
 */

#if SAM3S_SERIES || SAM4S_SERIES || SAM3N_SERIES
/**
 * \brief Initialize the given ADC with the specified ADC clock and startup time.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param ul_mck Main clock of the device (value in Hz).
 * \param ul_adc_clock Analog-to-Digital conversion clock (value in Hz).
 * \param uc_startup ADC start up time. Please refer to the product datasheet
 * for details.
 *
 * \return 0 on success.
 */
uint32_t adc_init(Adc *p_adc, const uint32_t ul_mck,
		const uint32_t ul_adc_clock, const uint8_t uc_startup)
{
	uint32_t ul_prescal;

	/*  Reset the controller. */
	p_adc->ADC_CR = ADC_CR_SWRST;

	/* Reset Mode Register. */
	p_adc->ADC_MR = 0;

	/* Reset PDC transfer. */
	p_adc->ADC_PTCR = (ADC_PTCR_RXTDIS | ADC_PTCR_TXTDIS);
	p_adc->ADC_RCR = 0;
	p_adc->ADC_RNCR = 0;

	ul_prescal = ul_mck / (2 * ul_adc_clock) - 1;
	p_adc->ADC_MR |= ADC_MR_PRESCAL(ul_prescal) |
			((uc_startup << ADC_MR_STARTUP_Pos) &
			ADC_MR_STARTUP_Msk);
	return 0;
}
#elif SAM3XA_SERIES
/**
 * \brief Initialize the given ADC with the specified ADC clock and startup time.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param ul_mck Main clock of the device (value in Hz).
 * \param ul_adc_clock Analog-to-Digital conversion clock (value in Hz).
 * \param uc_startup ADC start up time. Please refer to the product datasheet
 * for details.
 *
 * \return 0 on success.
 */
uint32_t adc_init(Adc *p_adc, const uint32_t ul_mck,
		const uint32_t ul_adc_clock, const uint8_t uc_startuptime)
{
	uint32_t startup_table[] = { 0, 8, 16, 24, 64, 80, 96, 112, 512, 576, 640, 704, 768, 832, 896, 960 };
	uint32_t ul_prescal, ul_startup,  ul_mr_startup, ul_real_adc_clock;
	p_adc->ADC_CR = ADC_CR_SWRST;

	/* Reset Mode Register. */
	p_adc->ADC_MR = 0;

	/* Reset PDC transfer. */
	p_adc->ADC_PTCR = (ADC_PTCR_RXTDIS | ADC_PTCR_TXTDIS);
	p_adc->ADC_RCR = 0;
	p_adc->ADC_RNCR = 0;
	if (ul_mck % (2 * ul_adc_clock)) {
		// Division with reminder
		ul_prescal = ul_mck / (2 * ul_adc_clock);
	} else {
		// Whole division
		ul_prescal = ul_mck / (2 * ul_adc_clock) - 1;
	}
	ul_real_adc_clock = ul_mck / (2 * (ul_prescal + 1));

	// ADC clocks needed to get ul_startuptime uS
	ul_startup = (ul_real_adc_clock / 1000000) * uc_startuptime;

	// Find correct MR_STARTUP value from conversion table
	for (ul_mr_startup=0; ul_mr_startup<16; ul_mr_startup++) {
		if (startup_table[ul_mr_startup] >= ul_startup)
			break;
	}
	if (ul_mr_startup==16)
		return -1;
	p_adc->ADC_MR |= ADC_MR_PRESCAL(ul_prescal) |
			((ul_mr_startup << ADC_MR_STARTUP_Pos) & ADC_MR_STARTUP_Msk);
	return 0;
}
#elif SAM3U_SERIES
/**
 * \brief Initialize the given ADC with the specified ADC clock and startup time.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param ul_mck Main clock of the device (value in Hz).
 * \param ul_adc_clock Analog-to-Digital conversion clock (in Hz).
 * \param ul_startuptime ADC startup time value (value in us).
 * Please refer to the product datasheet for details.
 * \param ul_offmode_startuptime  ADC off mode startup time value (in us).
 * Please refer to the product datasheet for details.
 *
 * \return 0 on success.
 */
uint32_t adc_init(Adc *p_adc, const uint32_t ul_mck, const uint32_t ul_adc_clock,
		const uint32_t ul_startuptime)
{
	uint32_t ul_prescal, ul_startup;
	p_adc->ADC_CR = ADC_CR_SWRST;

	/* Reset Mode Register. */
	p_adc->ADC_MR = 0;

	/* Reset PDC transfer. */
	p_adc->ADC_PTCR = (ADC_PTCR_RXTDIS | ADC_PTCR_TXTDIS);
	p_adc->ADC_RCR = 0;
	p_adc->ADC_RNCR = 0;
	ul_prescal = ul_mck / (2 * ul_adc_clock) - 1;
	ul_startup = ((ul_adc_clock / 1000000) * ul_startuptime / 8) - 1;
	p_adc->ADC_MR |= ADC_MR_PRESCAL(ul_prescal) |
			((ul_startup << ADC_MR_STARTUP_Pos) &
			ADC_MR_STARTUP_Msk);
	return 0;
}

#endif

/**
 * \brief Configure the conversion resolution.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param resolution ADC resolution.
 *
 */
void adc_set_resolution(Adc *p_adc,const enum adc_resolution_t resolution)
{
	p_adc->ADC_MR |= (resolution << 4) & ADC_MR_LOWRES;
}


#if SAM3S_SERIES || SAM4S_SERIES || SAM3N_SERIES || SAM3XA_SERIES
/**
 * \brief Configure conversion trigger and free run mode.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param trigger Conversion trigger.
 * \param uc_freerun ADC_MR_FREERUN_ON enables freerun mode,
 * ADC_MR_FREERUN_OFF disables freerun mode.
 *
 */
void adc_configure_trigger(Adc *p_adc, const enum adc_trigger_t trigger,
		uint8_t uc_freerun)
{
	p_adc->ADC_MR |= trigger | ((uc_freerun << 7) & ADC_MR_FREERUN);
}
#elif SAM3U_SERIES
/**
 * \brief Configure conversion trigger and free run mode.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param trigger Conversion trigger.
 */
void adc_configure_trigger(Adc *p_adc, const enum adc_trigger_t trigger)
{
	p_adc->ADC_MR |= trigger;
}
#endif

#if SAM3S_SERIES || SAM4S_SERIES || SAM3N_SERIES || SAM3XA_SERIES
/**
 * \brief Configures ADC power saving mode.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param uc_sleep ADC_MR_SLEEP_NORMAL keeps the ADC Core and reference voltage
 * circuitry ON between conversions.
 * ADC_MR_SLEEP_SLEEP keeps the ADC Core and reference voltage circuitry OFF
 * between conversions.
 * \param uc_fwup ADC_MR_FWUP_OFF configures sleep mode as uc_sleep setting,
 * ADC_MR_FWUP_ON keeps voltage reference ON and ADC Core OFF between conversions.
 */
void adc_configure_power_save(Adc *p_adc, const uint8_t uc_sleep, const uint8_t uc_fwup)
{
	p_adc->ADC_MR |= (((uc_sleep << 5) & ADC_MR_SLEEP) |
			((uc_fwup << 6) & ADC_MR_FWUP));
}
#elif SAM3U_SERIES
/**
 * \brief Configure ADC power saving mode.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param uc_sleep ADC_MR_SLEEP_NORMAL keeps the ADC Core and reference
 * voltage circuitry ON between conversions.
 * ADC_MR_SLEEP_SLEEP keeps the ADC Core and reference voltage circuitry
 * OFF between conversions.
 * \param uc_offmode 0 for Standby Mode (if Sleep Bit = 1), 1 for Off Mode.
 */
void adc_configure_power_save(Adc *p_adc, const uint8_t uc_sleep)
{
	p_adc->ADC_MR |= ((uc_sleep << 5) & ADC_MR_SLEEP);
}
#endif

#if SAM3S_SERIES || SAM4S_SERIES || SAM3N_SERIES || SAM3XA_SERIES
/**
 * \brief Configure conversion sequence.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param ch_list Channel sequence list.
 * \param number Number of channels in the list.
 */
void adc_configure_sequence(Adc *p_adc, const enum adc_channel_num_t ch_list[],
		uint8_t uc_num)
{
	uint8_t uc_counter;
	if (uc_num < 8) {
		for (uc_counter = 0; uc_counter < uc_num; uc_counter++) {
			p_adc->ADC_SEQR1 |=
					ch_list[uc_counter] << (4 * uc_counter);
		}
	} else {
		for (uc_counter = 0; uc_counter < 8; uc_counter++) {
			p_adc->ADC_SEQR1 |=
					ch_list[uc_counter] << (4 * uc_counter);
		}
		for (uc_counter = 0; uc_counter < uc_num - 8; uc_counter++) {
			p_adc->ADC_SEQR2 |=
					ch_list[uc_counter] << (4 * uc_counter);
		}
	}
}
#endif

#if SAM3S_SERIES || SAM4S_SERIES ||  SAM3XA_SERIES
/**
 * \brief Configure ADC timing.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param uc_tracking ADC tracking time = uc_tracking / ADC clock.
 * \param uc_settling Analog settling time = (uc_settling + 1) / ADC clock.
 * \param uc_transfer Data transfer time = (uc_transfer * 2 + 3) / ADC clock.
 */
void adc_configure_timing(Adc *p_adc, const uint8_t uc_tracking,
		const enum adc_settling_time_t settling,const uint8_t uc_transfer)
{
	p_adc->ADC_MR |= ADC_MR_TRANSFER(uc_transfer)
			| settling | ADC_MR_TRACKTIM(uc_tracking);
}
#elif  SAM3N_SERIES
/**
 * \brief Configure ADC timing.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param uc_tracking ADC tracking time = uc_tracking / ADC clock.
 */
void adc_configure_timing(Adc *p_adc, const uint8_t uc_tracking)
{
	p_adc->ADC_MR |= ADC_MR_TRACKTIM(uc_tracking);
}
#elif SAM3U_SERIES
/**
 * \brief Configure ADC timing.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param ul_sh ADC sample and hold time = uc_sh / ADC clock.
 */
void adc_configure_timing(Adc *p_adc, const uint32_t ul_sh)
{
	p_adc->ADC_MR |= ADC_MR_SHTIM(ul_sh);
}
#endif

#if SAM3S_SERIES || SAM4S_SERIES || SAM3XA_SERIES
/**
 * \brief Enable analog change.
 *
 * \note It allows different analog settings for each channel.
 *
 * \param p_Adc Pointer to an ADC instance.
 */
void adc_enable_anch(Adc *p_adc)
{
	p_adc->ADC_MR |= ADC_MR_ANACH;
}
#endif

#if SAM3S_SERIES || SAM4S_SERIES || SAM3XA_SERIES
/**
 * \brief Disable analog change.
 *
 * \note DIFF0, GAIN0 and OFF0 are used for all channels.
 *
 * \param p_Adc Pointer to an ADC instance.
 */
void adc_disable_anch(Adc *p_adc)
{
	p_adc->ADC_MR &= ~ADC_MR_ANACH;
}
#endif

/**
 * \brief Start analog-to-digital conversion.
 *
 * \note If one of the hardware event is selected as ADC trigger,
 * this function can NOT start analog to digital conversion.
 *
 * \param p_adc Pointer to an ADC instance.
 */

void adc_start(Adc *p_adc)
{
	p_adc->ADC_CR = ADC_CR_START;
}

/**
 * \brief Stop analog-to-digital conversion.
 *
 * \param p_adc Pointer to an ADC instance.
 */
void adc_stop(Adc *p_adc)
{
	p_adc->ADC_CR = ADC_CR_SWRST;
}

/**
 * \brief Enable the specified ADC channel.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param adc_ch ADC channel number.
 */
void adc_enable_channel(Adc *p_adc, const enum adc_channel_num_t adc_ch)
{
	p_adc->ADC_CHER = 1 << adc_ch;
}

/**
 * \brief Enable all ADC channels.
 *
 * \param p_adc Pointer to an ADC instance.
 */
void adc_enable_all_channel(Adc *p_adc)
{
#if SAM3S_SERIES || SAM4S_SERIES || SAM3N_SERIES || SAM3XA_SERIES
	p_adc->ADC_CHER = 0xFFFF;
#elif SAM3U_SERIES
	p_adc->ADC_CHER = 0xFF;
#endif
}

/**
 * \brief Disable the specified ADC channel.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param adc_ch ADC channel number.
 */
void adc_disable_channel(Adc *p_adc, const enum adc_channel_num_t adc_ch)
{
	p_adc->ADC_CHDR = 1 << adc_ch;
}

/**
 * \brief Disable all ADC channel.
 *
 * \param p_adc Pointer to an ADC instance.
 */
void adc_disable_all_channel(Adc *p_adc)
{
#if SAM3S_SERIES || SAM4S_SERIES || SAM3N_SERIES || SAM3XA_SERIES
	p_adc->ADC_CHDR = 0xFFFF;
#elif SAM3U_SERIES
	p_adc->ADC_CHDR = 0xFF;
#endif
}

/**
 * \brief Read the ADC channel status.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param adc_ch ADC channel number.
 *
 * \retval 1 if channel is enabled.
 * \retval 0 if channel is disabled.
 */
uint32_t adc_get_channel_status(const Adc *p_adc, const enum adc_channel_num_t adc_ch)
{
	return p_adc->ADC_CHSR & (1 << adc_ch);
}

/**
 * \brief Read the ADC result data of the specified channel.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param adc_ch ADC channel number.
 *
 * \return ADC value of the specified channel.
 */
uint32_t adc_get_channel_value(const Adc *p_adc, const enum adc_channel_num_t adc_ch)
{
	uint32_t ul_data = 0;

	if (15 >= adc_ch) {
		ul_data = *(p_adc->ADC_CDR + adc_ch);
	}

	return ul_data;
}

/**
 * \brief Read the last ADC result data.
 *
 * \param p_adc Pointer to an ADC instance.
 *
 * \return ADC latest value.
 */
uint32_t adc_get_latest_value(const Adc *p_adc)
{
	return p_adc->ADC_LCDR;
}

#if SAM3S_SERIES || SAM4S_SERIES || SAM3N_SERIES || SAM3XA_SERIES
/**
 * \brief Enable TAG option so that the number of the last converted channel
 * can be indicated.
 *
 * \param p_adc Pointer to an ADC instance.
 */
void adc_enable_tag(Adc *p_adc)
{
	p_adc->ADC_EMR |= ADC_EMR_TAG;
}
#endif

#if SAM3S_SERIES || SAM4S_SERIES || SAM3N_SERIES || SAM3XA_SERIES
/**
 * \brief Disable TAG option.
 *
 * \param p_adc Pointer to an ADC instance.
 */
void adc_disable_tag(Adc *p_adc)
{
	p_adc->ADC_EMR &= ~ADC_EMR_TAG;
}
#endif

#if SAM3S_SERIES || SAM4S_SERIES || SAM3N_SERIES || SAM3XA_SERIES
/**
 * \brief Indicate the last converted channel.
 *
 * \note If TAG option is NOT enabled before, an incorrect channel
 * number is returned.
 *
 * \param p_adc Pointer to an ADC instance.
 *
 * \return The last converted channel number.
 */
enum adc_channel_num_t adc_get_tag(const Adc *p_adc)
{
	return (p_adc->ADC_LCDR & ADC_LCDR_CHNB_Msk) >> ADC_LCDR_CHNB_Pos;
}
#endif

#if SAM3S_SERIES || SAM4S_SERIES || SAM3N_SERIES || SAM3XA_SERIES
/**
 * \brief Enable conversion sequencer.
 *
 * \param p_adc Pointer to an ADC instance.
 */
void adc_start_sequencer(Adc *p_adc)
{
	p_adc->ADC_MR |= ADC_MR_USEQ;
}
#endif

#if SAM3S_SERIES || SAM4S_SERIES || SAM3N_SERIES || SAM3XA_SERIES
/**
 * \brief Disable conversion sequencer.
 *
 * \param p_adc Pointer to an ADC instance.
 */
void adc_stop_sequencer(Adc *p_adc)
{
	p_adc->ADC_MR &= ~ADC_MR_USEQ;
}
#endif

#if SAM3S_SERIES || SAM4S_SERIES || SAM3N_SERIES || SAM3XA_SERIES
/**
 * \brief Configure comparison mode.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param uc_mode ADC comparison mode.
 */
void adc_set_comparison_mode(Adc *p_adc, const uint8_t uc_mode)
{
	p_adc->ADC_EMR &= (uint32_t) ~ (ADC_EMR_CMPMODE_Msk);
	p_adc->ADC_EMR |= (uc_mode & ADC_EMR_CMPMODE_Msk);
}
#endif

#if SAM3S_SERIES || SAM4S_SERIES || SAM3N_SERIES || SAM3XA_SERIES
/**
 * \brief Get comparison mode.
 *
 * \param p_adc Pointer to an ADC instance.
 *
 * \retval Compare mode value.
 */
uint32_t adc_get_comparison_mode(const Adc *p_adc)
{
	return p_adc->ADC_EMR & ADC_EMR_CMPMODE_Msk;
}
#endif

#if SAM3S_SERIES || SAM4S_SERIES || SAM3N_SERIES || SAM3XA_SERIES
/**
 * \brief Configure ADC compare window.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param w_low_threshold Low threshold of compare window.
 * \param w_high_threshold High threshold of compare window.
 */
void adc_set_comparison_window(Adc *p_adc, const uint16_t us_low_threshold,
		const uint16_t us_high_threshold)
{
	p_adc->ADC_CWR = ADC_CWR_LOWTHRES(us_low_threshold) |
			ADC_CWR_HIGHTHRES(us_high_threshold);
}
#endif

#if SAM3S_SERIES || SAM4S_SERIES || SAM3N_SERIES || SAM3XA_SERIES
/**
 * \brief Configure comparison selected channel.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param channel ADC channel number.
 */
void adc_set_comparison_channel(Adc *p_adc, const enum adc_channel_num_t channel)
{
	if (channel < 16) {
		p_adc->ADC_EMR &= (uint32_t) ~ (ADC_EMR_CMPALL);
		p_adc->ADC_EMR &= (uint32_t) ~ (ADC_EMR_CMPSEL_Msk);
		p_adc->ADC_EMR |= (channel << ADC_EMR_CMPSEL_Pos);
	} else {
		p_adc->ADC_EMR |= ADC_EMR_CMPALL;
	}
}
#endif

#if SAM3S_SERIES || SAM4S_SERIES || SAM3XA_SERIES
/**
 * \brief Enable differential input for the specified channel.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param channel ADC channel number.
 */
void adc_enable_channel_differential_input(Adc *p_adc, const enum adc_channel_num_t channel)
{
	p_adc->ADC_COR |= 0x01u << (16 + channel);
}
#endif

#if SAM3S_SERIES || SAM4S_SERIES || SAM3XA_SERIES
/**
 * \brief Disable differential input for the specified channel.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param channel ADC channel number.
 */
void adc_disable_channel_differential_input(Adc *p_adc, const enum adc_channel_num_t channel)
{
	uint32_t ul_temp;
	ul_temp = p_adc->ADC_COR;
	p_adc->ADC_COR &= 0xfffeffffu << channel;
	p_adc->ADC_COR |= ul_temp;
}
#endif

#if SAM3S_SERIES || SAM4S_SERIES || SAM3XA_SERIES
/**
 * \brief Enable analog signal offset for the specified channel.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param channel ADC channel number.
 */
void adc_enable_channel_input_offset(Adc *p_adc, const enum adc_channel_num_t channel)
{
	p_adc->ADC_COR |= 0x01u << channel;
}
#endif

#if SAM3S_SERIES || SAM4S_SERIES || SAM3XA_SERIES
/**
 * \brief Disable analog signal offset for the specified channel.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param channel ADC channel number.
 */
void adc_disable_channel_input_offset(Adc *p_adc, const enum adc_channel_num_t channel)
{
	uint32_t ul_temp;
	ul_temp = p_adc->ADC_COR;
	p_adc->ADC_COR &= (0xfffffffeu << channel);
	p_adc->ADC_COR |= ul_temp;
}
#endif

#if SAM3S_SERIES || SAM4S_SERIES || SAM3XA_SERIES
/**
 * \brief Configure input gain for the specified channel.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param channel ADC channel number.
 * \param gain Gain value for the input.
 */
void adc_set_channel_input_gain(Adc *p_adc, const enum adc_channel_num_t channel,
		const enum adc_gainvalue_t gain)
{
	p_adc->ADC_CGR |= (0x03u << (2 * channel)) & (gain << (2 * channel));
}
#endif

#if SAM3SD8_SERIES || SAM4S_SERIES
/**
 * \brief Set ADC auto calibration mode.
 *
 * \param p_adc Pointer to an ADC instance.
 */
void adc_set_calibmode(Adc * p_adc)
{
	p_adc->ADC_CR |= ADC_CR_AUTOCAL;
}
#endif

/**
 * \brief Return the actual ADC clock.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param ul_mck Main clock of the device (in Hz).
 *
 * \return The actual ADC clock (in Hz).
 */
uint32_t adc_get_actual_adc_clock(const Adc *p_adc, const uint32_t ul_mck)
{
	uint32_t ul_adcfreq;
	uint32_t ul_prescal;

	/* ADCClock = MCK / ( (PRESCAL+1) * 2 ) */
	ul_prescal = ((p_adc->ADC_MR & ADC_MR_PRESCAL_Msk) >> ADC_MR_PRESCAL_Pos);
	ul_adcfreq = ul_mck / ((ul_prescal + 1) * 2);
	return ul_adcfreq;
}

/**
 * \brief Enable ADC interrupts.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param ul_source Interrupts to be enabled.
 */
void adc_enable_interrupt(Adc *p_adc, const uint32_t ul_source)
{
	p_adc->ADC_IER = ul_source;
}

/**
 * \brief Disable ADC interrupts.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param ul_source Interrupts to be disabled.
 */
void adc_disable_interrupt(Adc *p_adc, const uint32_t ul_source)
{
	p_adc->ADC_IDR = ul_source;
}

#if SAM3S_SERIES || SAM4S_SERIES || SAM3N_SERIES || SAM3XA_SERIES
/**
 * \brief Get ADC interrupt and overrun error status.
 *
 * \param p_adc Pointer to an ADC instance.
 *
 * \return ADC status structure.
 */
uint32_t adc_get_status(const Adc *p_adc)
{
	return p_adc->ADC_ISR;
}

/**
 * \brief Get ADC interrupt and overrun error status.
 *
 * \param p_adc Pointer to an ADC instance.
 *
 * \return ADC status structure.
 */
uint32_t adc_get_overrun_status(const Adc *p_adc)
{
	return p_adc->ADC_OVER;
}
#elif SAM3U_SERIES
/**
 * \brief Read ADC interrupt and overrun error status.
 *
 * \param p_adc Pointer to an ADC instance.
 *
 * \retval ADC status structure.
 */
uint32_t adc_get_status(const Adc *p_adc)
{
	return p_adc->ADC_SR;
}
#endif

/**
 * \brief Read ADC interrupt mask.
 *
 * \param p_adc Pointer to an ADC instance.
 *
 * \return The interrupt mask value.
 */
uint32_t adc_get_interrupt_mask(const Adc *p_adc)
{
	return p_adc->ADC_IMR;
}

#if SAM3S_SERIES || SAM4S_SERIES || SAM3XA_SERIES
/**
 * \brief Adapt performance versus power consumption.
 *
 * \note Please refer to ADC Characteristics in the product datasheet
 * for more details.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param ibctl ADC Bias current control.
 */
void adc_set_bias_current(Adc *p_adc, const uint8_t uc_ibctl)
{
	p_adc->ADC_ACR |= ADC_ACR_IBCTL(uc_ibctl);
}
#endif

#if SAM3S_SERIES || SAM4S_SERIES || SAM3XA_SERIES
/**
 * \brief Turn on temperature sensor.
 *
 * \param p_adc Pointer to an ADC instance.
 */
void adc_enable_ts(Adc *p_adc)
{
	p_adc->ADC_ACR |= ADC_ACR_TSON;
}
#endif

#if SAM3S_SERIES || SAM4S_SERIES || SAM3XA_SERIES
/**
 * \brief Turn off temperature sensor.
 *
 * \param p_adc Pointer to an ADC instance.
 */
void adc_disable_ts(Adc *p_adc)
{
	p_adc->ADC_ACR &= ~ADC_ACR_TSON;
}
#endif

#if SAM3S_SERIES || SAM4S_SERIES || SAM3N_SERIES || SAM3XA_SERIES
/**
 * \brief Enable or disable write protection of ADC registers.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param ul_enable 1 to enable, 0 to disable.
 */
void adc_set_writeprotect(Adc *p_adc, const uint32_t ul_enable)
{
	p_adc->ADC_WPMR |= ADC_WPMR_WPKEY(ul_enable);
}
#endif

#if SAM3S_SERIES || SAM4S_SERIES || SAM3N_SERIES || SAM3XA_SERIES
/**
 * \brief Indicate write protect status.
 *
 * \param p_adc Pointer to an ADC instance.
 *
 * \return 0 if the peripheral is not protected, or 16-bit write protect
 * violation Status.
 */
uint32_t adc_get_writeprotect_status(const Adc *p_adc)
{
	return p_adc->ADC_WPSR & ADC_WPSR_WPVS;
}
#endif

#if 0
/**
 * \brief calcul_startup
 */
static uint32_t calcul_startup(const uint32_t ul_startup)
{
	uint32_t ul_startup_value = 0;

	if (ul_startup == 0)
		ul_startup_value = 0;
	else if (ul_startup == 1)
		ul_startup_value = 8;
	else if (ul_startup == 2)
		ul_startup_value = 16;
	else if (ul_startup == 3)
		ul_startup_value = 24;
	else if (ul_startup == 4)
		ul_startup_value = 64;
	else if (ul_startup == 5)
		ul_startup_value = 80;
	else if (ul_startup == 6)
		ul_startup_value = 96;
	else if (ul_startup == 7)
		ul_startup_value = 112;
	else if (ul_startup == 8)
		ul_startup_value = 512;
	else if (ul_startup == 9)
		ul_startup_value = 576;
	else if (ul_startup == 10)
		ul_startup_value = 640;
	else if (ul_startup == 11)
		ul_startup_value = 704;
	else if (ul_startup == 12)
		ul_startup_value = 768;
	else if (ul_startup == 13)
		ul_startup_value = 832;
	else if (ul_startup == 14)
		ul_startup_value = 896;
	else if (ul_startup == 15)
		ul_startup_value = 960;

	return ul_startup_value;
}

/**
 * \brief Check ADC configurations.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param ul_mck Main clock of the device (in Hz).
 */
void adc_check(Adc *p_adc, const uint32_t ul_mck)
{
	uint32_t ul_adcfreq;
	uint32_t ul_prescal;
	uint32_t ul_startup;

	/* ADCClock = MCK / ( (PRESCAL+1) * 2 ) */
	ul_prescal = ((p_adc->ADC_MR & ADC_MR_PRESCAL_Msk) >>
			ADC_MR_PRESCAL_Pos);
	ul_adcfreq = ul_mck / ((ul_prescal + 1) * 2);
	printf("ADC clock frequency = %d Hz\r\n", (int)ul_adcfreq);

	if (ul_adcfreq < ADC_FREQ_MIN) {
		printf("adc frequency too low (out of specification: %d Hz)\r\n",
			(int)ADC_FREQ_MIN);
	}
	if (ul_adcfreq > ADC_FREQ_MAX) {
		printf("adc frequency too high (out of specification: %d Hz)\r\n",
			(int)ADC_FREQ_MAX);
	}

	ul_startup = ((p_adc->ADC_MR & ADC_MR_STARTUP_Msk) >>
			ADC_MR_STARTUP_Pos);
	if (!(p_adc->ADC_MR & ADC_MR_SLEEP_SLEEP)) {
		/* 40ms */
		if (ADC_STARTUP_NORM * ul_adcfreq / 1000000 >
				calcul_startup(ul_startup)) {
			printf("Startup time too small: %d, programmed: %d\r\n",
					(int)(ADC_STARTUP_NORM * ul_adcfreq /
							1000000),
					(int)calcul_startup(ul_startup));
		}
	} else {
		if (p_adc->ADC_MR & ADC_MR_FREERUN_ON) {
			puts("FreeRun forbidden in sleep mode\r");
		}
		if (!(p_adc->ADC_MR & ADC_MR_FWUP_ON)) {
			/* Sleep 40ms */
			if (ADC_STARTUP_NORM * ul_adcfreq / 1000000 >
					calcul_startup(ul_startup)) {
				printf("Startup time too small: %d, programmed: %d\r\n",
					(int)(ADC_STARTUP_NORM * ul_adcfreq / 1000000),
					(int)(calcul_startup(ul_startup)));
			}
		} else {
			if (p_adc->ADC_MR & ADC_MR_FWUP_ON) {
				/* Fast Wake Up Sleep Mode: 12ms */
				if (ADC_STARTUP_FAST * ul_adcfreq / 1000000 >
						calcul_startup(ul_startup)) {
					printf("Startup time too small: %d, programmed: %d\r\n",
						(int)(ADC_STARTUP_NORM * ul_adcfreq / 1000000),
						(int)(calcul_startup(ul_startup)));
				}
			}
		}
	}
}
#endif

/**
 * \brief Get PDC registers base address.
 *
 * \param p_adc Pointer to an ADC instance.
 *
 * \return ADC PDC register base address.
 */
Pdc *adc_get_pdc_base(const Adc *p_adc)
{
	return PDC_ADC;
}

//@}

/// @cond 0
/**INDENT-OFF**/
#ifdef __cplusplus
}
#endif
/**INDENT-ON**/
/// @endcond