/* ----------------------------------------------------------------------------
 *         SAM Software Package License
 * ----------------------------------------------------------------------------
 * Copyright (c) 2015, Atmel Corporation
 *
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 * modification, are permitted provided that the following conditions are met:
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/**
 *  \file
 *
 *  \par Purpose
 *
 *  Methods and definitions for an internal timer.
 *
 *  Defines a common and simpliest use of timer to generate delays using PIT
 *
 *  \par Usage
 *
 *  -# Configure the System Tick with timer_configure() when MCK changed
 *     \note
 *     Must be done before any invoke of timer_wait(), or timer_sleep()
 *  -# Uses timer_wait to actively wait according to your timer resolution.
 *  -# Uses timer_sleep to passively wait ccording to your timer resolution.
 *
 */

#ifndef TIMER_HEADER_
#define TIMER_HEADER_

/*----------------------------------------------------------------------------
 *         Headers
 *----------------------------------------------------------------------------*/

#include <stdint.h>

struct _timeout
{
	uint32_t start;
	uint32_t count;
};
/*----------------------------------------------------------------------------
 *         Global functions
 *----------------------------------------------------------------------------*/

/**
 *  \brief Configures the PIT & reset _timer.
 *  Systick interrupt handler will generates 1ms interrupt and increase a
 *  tickCount.
 *
 *  \note PIT is enabled automatically in this function.
 *  \warning This function also set PIT handler to aic which is
 *  mandatory to make the timer API work
 *
 *  \param resolution initialize PIT resolution (in nano seconds)
 */
extern uint32_t timer_configure(uint32_t resolution);

/**
 *  \brief Sync wait for count times resoltion
 */
extern void timer_wait(uint32_t count);

/**
 * \brief Retrieve current timer resolution.
 *
 * \return Current timer resolution (0 if not already set)
 */
extern uint32_t timer_get_resolution(void);

/**
 *  \brief Sync sleep for count times resolution
 */
extern void timer_sleep(uint32_t count);

/**
 *  \brief Initialize a timeout
 */
extern void timer_start_timeout(struct _timeout* timeout, uint32_t count);

/**
 *  \brief Tells if the timeout as been reached
 */
extern uint8_t timer_timeout_reached(struct _timeout* timeout);

/**
 * \brief Compute elapsed number of ticks between start and end with
 * taking overlaps into accounts
 *
 * \param start Start tick point.
 * \param end End tick point.
 */
extern uint32_t timer_get_interval(uint32_t start, uint32_t end);

/**
 * \brief Returns the current number of ticks
 */
extern uint32_t timer_get_tick(void);

#endif /* TIMER_HEADER_ */