/*****************************************************************************
 *
 * \file
 *
 * \brief RTC driver for AVR32 UC3.
 *
 * AVR32 Real Time Counter driver module.
 *
 * 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
 *
 ******************************************************************************/


#ifndef _RTC_H_
#define _RTC_H_

/**
 * \defgroup group_avr32_drivers_rtc TIMING - RTC - Real Time Counter
 *
 * Driver for the RTC (32-bit Real Time Counter).
 * The RTC enables periodic interrupts at long intervals,
 * or accurate measurement of real-time sequences. Can be clocked from
 * internal RC oscillator or external 32 kHz crystal.
 *
 * \{
 */

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


/*! \name Oscillator Types
 */
//! @{
#define RTC_OSC_32KHZ    1
#define RTC_OSC_RC       0
//! @}

/*! \name Predefined PSEL Values
 */
//! @{

//! The PSEL value to set the RTC source clock (after the prescaler) to 1 Hz,
//! when using an external 32-kHz crystal.
#define RTC_PSEL_32KHZ_1HZ    14

//! The PSEL value to set the RTC source clock (after the prescaler) to 1.76 Hz,
//! when using the internal RC oscillator (~ 115 kHz).
#define RTC_PSEL_RC_1_76HZ    15

//! @}


/*!
 * \brief This function will initialise the RTC module.
 *        If you use the 32 KHz oscillator, it will enable this module.
 *        This function also set the top value of the RTC to 0xFFFFFFFF
 *        and the value to 0.
 * \param rtc Base address of the RTC (i.e. &AVR32_RTC).
 * \param osc_type The oscillator you want to use. If you need a better
 *        accuracy, use the 32 KHz oscillator (i.e. RTC_OSC_32KHZ).
 * \param psel The preselector value for the corresponding oscillator (4-bits).
 *        To obtain this value, you can use this formula:
 *        psel = log(Fosc/Frtc)/log(2)-1, where Fosc is the frequency of the
 *        oscillator you are using (32 KHz or 115 KHz) and Frtc the frequency
 *        desired.
 * \return 1 if the initialisation succeds otherwize it will return 0.
 */
extern int rtc_init(volatile avr32_rtc_t *rtc, unsigned char osc_type, unsigned char psel);

/*!
 * \brief Enable the RTC.
 * \param rtc Base address of the RTC (i.e. &AVR32_RTC).
 */
extern void rtc_enable(volatile avr32_rtc_t *rtc);

/*!
 * \brief Disable the RTC.
 * \param rtc Base address of the RTC (i.e. &AVR32_RTC).
 */
extern void rtc_disable(volatile avr32_rtc_t *rtc);

/*!
 * \brief Enable the wake up feature of the RTC.
 * \param rtc Base address of the RTC (i.e. &AVR32_RTC).
 */
extern void rtc_enable_wake_up(volatile avr32_rtc_t *rtc);

/*!
 * \brief Disable the wake up feature of the RTC.
 * \param rtc Base address of the RTC (i.e. &AVR32_RTC).
 */
extern void rtc_disable_wake_up(volatile avr32_rtc_t *rtc);

/*!
 * \brief Enable the interrupt feature of the RTC.
 *        An interrupt is raised when the value of the RTC
 *        is equal to its top value.
 * \param rtc Base address of the RTC (i.e. &AVR32_RTC).
 */
extern void rtc_enable_interrupt(volatile avr32_rtc_t *rtc);

/*!
 * \brief Disable the interrupt feature of the RTC.
 * \param rtc Base address of the RTC (i.e. &AVR32_RTC).
 */
extern void rtc_disable_interrupt(volatile avr32_rtc_t *rtc);

/*!
 * \brief Clear the interrupt flag.
 *        Call this function once you handled the interrupt.
 * \param rtc Base address of the RTC (i.e. &AVR32_RTC).
 */
extern void rtc_clear_interrupt(volatile avr32_rtc_t *rtc);

/*!
 * \brief Get the status of interrupts.
 * \param rtc Base address of the RTC (i.e. &AVR32_RTC).
 * \return 1 if the interrupts are enabled otherwize it returns 0.
 */
extern int rtc_interrupt_enabled(volatile avr32_rtc_t *rtc);

/*!
 * \brief Check if an interrupt is raised.
 * \param rtc Base address of the RTC (i.e. &AVR32_RTC).
 * \return 1 if an interrupt is currently raised otherwize it returns 0.
 */
extern int rtc_is_interrupt(volatile avr32_rtc_t *rtc);

/*!
 * \brief This function sets the RTC current top value.
 * \param rtc Base address of the RTC (i.e. &AVR32_RTC).
 * \param top The top value you want to store.
 */
extern void rtc_set_top_value(volatile avr32_rtc_t *rtc, unsigned long top);

/*!
 * \brief This function returns the RTC current top value.
 * \param rtc Base address of the RTC (i.e. &AVR32_RTC).
 * \return The RTC current top value.
 */
extern unsigned long rtc_get_top_value(volatile avr32_rtc_t *rtc);

/*!
 * \brief This function checks if the RTC is busy or not.
 * \param rtc Base address of the RTC (i.e. &AVR32_RTC).
 * \return 1 if the RTC is busy otherwize it will return 0.
 */
extern int rtc_is_busy(volatile avr32_rtc_t *rtc);

/*!
 * \brief This function sets the RTC current value.
 * \param rtc Base address of the RTC (i.e. &AVR32_RTC).
 * \param val The value you want to store.
 */
extern void rtc_set_value(volatile avr32_rtc_t *rtc, unsigned long val);

/*!
 * \brief This function returns the RTC current value.
 * \param rtc Base address of the RTC (i.e. &AVR32_RTC).
 * \return The RTC current value.
 */
extern unsigned long rtc_get_value(volatile avr32_rtc_t *rtc);

/**
 * \}
 */

#endif  // _RTC_H_
