/*
    ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
                 2011,2012,2013 Giovanni Di Sirio.

    This file is part of ChibiOS/RT.

    ChibiOS/RT is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.

    ChibiOS/RT is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/
/*
   Concepts and parts of this file have been contributed by Fabio Utzig and
   Xo Wang.
 */

/**
 * @file    templates/icu_lld.h
 * @brief   ICU Driver subsystem low level driver header template.
 *
 * @addtogroup ICU
 * @{
 */

#ifndef _ICU_LLD_H_
#define _ICU_LLD_H_

#if HAL_USE_ICU || defined(__DOXYGEN__)

/*===========================================================================*/
/* Driver constants.                                                         */
/*===========================================================================*/

/*===========================================================================*/
/* Driver pre-compile time settings.                                         */
/*===========================================================================*/

/**
 * @name    Configuration options
 * @{
 */
/**
 * @brief   ICU driver enable switch.
 * @details If set to @p TRUE the support for ICU1 is included.
 */
#if !defined(PLATFORM_ICU_USE_ICU1) || defined(__DOXYGEN__)
#define PLATFORM_ICU_USE_ICU1             FALSE
#endif
/** @} */

/*===========================================================================*/
/* Derived constants and error checks.                                       */
/*===========================================================================*/

/*===========================================================================*/
/* Driver data structures and types.                                         */
/*===========================================================================*/

/**
 * @brief ICU driver mode.
 */
typedef enum {
  ICU_INPUT_ACTIVE_HIGH = 0,        /**< Trigger on rising edge.            */
  ICU_INPUT_ACTIVE_LOW = 1,         /**< Trigger on falling edge.           */
} icumode_t;

/**
 * @brief   ICU frequency type.
 */
typedef uint32_t icufreq_t;

/**
 * @brief   ICU counter type.
 */
typedef uint16_t icucnt_t;

/**
 * @brief   Driver configuration structure.
 * @note    It could be empty on some architectures.
 */
typedef struct {
  /**
   * @brief   Driver mode.
   */
  icumode_t                 mode;
  /**
   * @brief   Timer clock in Hz.
   * @note    The low level can use assertions in order to catch invalid
   *          frequency specifications.
   */
  icufreq_t                 frequency;
  /**
   * @brief   Callback for pulse width measurement.
   */
  icucallback_t             width_cb;
  /**
   * @brief   Callback for cycle period measurement.
   */
  icucallback_t             period_cb;
  /**
   * @brief   Callback for timer overflow.
   */
  icucallback_t             overflow_cb;
  /* End of the mandatory fields.*/
} ICUConfig;

/**
 * @brief   Structure representing an ICU driver.
 */
struct ICUDriver {
  /**
   * @brief Driver state.
   */
  icustate_t                state;
  /**
   * @brief Current configuration data.
   */
  const ICUConfig           *config;
#if defined(ICU_DRIVER_EXT_FIELDS)
  ICU_DRIVER_EXT_FIELDS
#endif
  /* End of the mandatory fields.*/
};

/*===========================================================================*/
/* Driver macros.                                                            */
/*===========================================================================*/

/*===========================================================================*/
/* External declarations.                                                    */
/*===========================================================================*/

#if PLATFORM_ICU_USE_ICU1 && !defined(__DOXYGEN__)
extern ICUDriver ICUD1;
#endif

#ifdef __cplusplus
extern "C" {
#endif
  void icu_lld_init(void);
  void icu_lld_start(ICUDriver *icup);
  void icu_lld_stop(ICUDriver *icup);
  void icu_lld_enable(ICUDriver *icup);
  void icu_lld_disable(ICUDriver *icup);
  icucnt_t icu_lld_get_width(ICUDriver *icup);
  icucnt_t icu_lld_get_period(ICUDriver *icup);
#ifdef __cplusplus
}
#endif

#endif /* HAL_USE_ICU */

#endif /* _ICU_LLD_H_ */

/** @} */