text: /**
   * Copyright (c) 2016 - 2018, Nordic Semiconductor ASA
   *
   *
   *
   * 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, except as embedded into a Nordic
   *    Semiconductor ASA integrated circuit in a product or a software update for
   *    such product, 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. Neither the name of Nordic Semiconductor ASA nor the names of its
   *    contributors may be used to endorse or promote products derived from this
   *    software without specific prior written permission.
   *
   * 4. This software, with or without modification, must only be used with a
   *    Nordic Semiconductor ASA integrated circuit.
   *
   * 5. Any software provided in binary form under this license must not be reverse
   *    engineered, decompiled, modified and/or disassembled.
   *
   * THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS
   * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
   * OF MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE ARE
   * DISCLAIMED. IN NO EVENT SHALL NORDIC SEMICONDUCTOR ASA OR CONTRIBUTORS 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.
   *
   */
  #ifndef NRF_DRV_CLOCK_H__
  #define NRF_DRV_CLOCK_H__
  
  #include <nrfx_clock.h>
  
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  /**
   * @defgroup nrf_drv_clock Clock driver - legacy layer
   * @{
   * @ingroup nrf_clock
   *
   * @brief Layer providing compatibility with the former API.
   */
  
  /**
   * @brief Clock events.
   */
  typedef enum
  {
      NRF_DRV_CLOCK_EVT_HFCLK_STARTED, ///< HFCLK has been started.
      NRF_DRV_CLOCK_EVT_LFCLK_STARTED, ///< LFCLK has been started.
      NRF_DRV_CLOCK_EVT_CAL_DONE,      ///< Calibration is done.
      NRF_DRV_CLOCK_EVT_CAL_ABORTED,   ///< Calibration has been aborted.
  } nrf_drv_clock_evt_type_t;
  
  /**
   * @brief Clock event handler.
   *
   * @param[in] event  Event.
   */
  typedef void (*nrf_drv_clock_event_handler_t)(nrf_drv_clock_evt_type_t event);
  
  // Forward declaration of the nrf_drv_clock_handler_item_t type.
  typedef struct nrf_drv_clock_handler_item_s nrf_drv_clock_handler_item_t;
  
  struct nrf_drv_clock_handler_item_s
  {
      nrf_drv_clock_handler_item_t * p_next;        ///< A pointer to the next handler that should be called when the clock is started.
      nrf_drv_clock_event_handler_t  event_handler; ///< Function to be called when the clock is started.
  };
  
  /**
   * @brief Function for checking if driver is already initialized
   *
   * @retval true  Driver is initialized
   * @retval false Driver is uninitialized
   */
  bool nrf_drv_clock_init_check(void);
  
  /**
   * @brief Function for initializing the nrf_drv_clock module.
   *
   * After initialization, the module is in power off state (clocks are not requested).
   *
   * @retval NRF_SUCCESS                          If the procedure was successful.
   * @retval NRF_ERROR_MODULE_ALREADY_INITIALIZED If the driver was already initialized.
   */
  ret_code_t nrf_drv_clock_init(void);
  
  /**
   * @brief Function for uninitializing the clock module.
   *
   */
  void nrf_drv_clock_uninit(void);
  
  /**
   * @brief Function for requesting the LFCLK.
   *
   * The low-frequency clock can be requested by different modules
   * or contexts. The driver ensures that the clock will be started only when it is requested
   * the first time. If the clock is not ready but it was already started, the handler item that is
   * provided as an input parameter is added to the list of handlers that will be notified
   * when the clock is started. If the clock is already enabled, user callback is called from the
   * current context.
   *
   * The first request will start the selected LFCLK source. If an event handler is
   * provided, it will be called once the LFCLK is started. If the LFCLK was already started at this
   * time, the event handler will be called from the context of this function. Additionally,
   * the @ref nrf_drv_clock_lfclk_is_running function can be polled to check if the clock has started.
   *
   * @note When a SoftDevice is enabled, the LFCLK is always running and the driver cannot control it.
   *
   * @note The handler item provided by the user cannot be an automatic variable.
   *
   * @param[in] p_handler_item A pointer to the event handler structure.
   */
  void nrf_drv_clock_lfclk_request(nrf_drv_clock_handler_item_t * p_handler_item);
  
  /**
   * @brief Function for releasing the LFCLK.
   *
   * If there are no more requests, the LFCLK source will be stopped.
   *
   * @note When a SoftDevice is enabled, the LFCLK is always running.
   */
  void nrf_drv_clock_lfclk_release(void);
  
  /**
   * @brief Function for checking the LFCLK state.
   *
   * @retval true  If the LFCLK is running.
   * @retval false If the LFCLK is not running.
   */
  bool nrf_drv_clock_lfclk_is_running(void);
  
  /**
   * @brief Function for requesting the high-accuracy source HFCLK.
   *
   * The high-accuracy source
   * can be requested by different modules or contexts. The driver ensures that the high-accuracy
   * clock will be started only when it is requested the first time. If the clock is not ready
   * but it was already started, the handler item that is provided as an input parameter is added
   * to the list of handlers that will be notified when the clock is started.
   *
   * If an event handler is provided, it will be called once the clock is started. If the clock was already
   * started at this time, the event handler will be called from the context of this function. Additionally,
   * the @ref nrf_drv_clock_hfclk_is_running function can be polled to check if the clock has started.
   *
   * @note If a SoftDevice is running, the clock is managed by the SoftDevice and all requests are handled by
   *       the SoftDevice. This function cannot be called from all interrupt priority levels in that case.
   * @note The handler item provided by the user cannot be an automatic variable.
   *
   * @param[in] p_handler_item A pointer to the event handler structure.
   */
  void nrf_drv_clock_hfclk_request(nrf_drv_clock_handler_item_t * p_handler_item);
  
  /**
   * @brief Function for releasing the high-accuracy source HFCLK.
   *
   * If there are no more requests, the high-accuracy source will be released.
   */
  void nrf_drv_clock_hfclk_release(void);
  
  /**
   * @brief Function for checking the HFCLK state.
   *
   * @retval true If the HFCLK is running (for \nRFXX XTAL source).
   * @retval false If the HFCLK is not running.
   */
  bool nrf_drv_clock_hfclk_is_running(void);
  
  /**
   * @brief Function for starting a single calibration process.
   *
   * This function can also delay the start of calibration by a user-specified value. The delay will use
   * a low-power timer that is part of the CLOCK module. @ref nrf_drv_clock_is_calibrating can be called to
   * check if calibration is still in progress. If a handler is provided, the user can be notified when
   * calibration is completed. The ext calibration can be started from the handler context.
   *
   * The calibration process consists of three phases:
   * - Delay (optional)
   * - Requesting the high-accuracy HFCLK
   * - Hardware-supported calibration
   *
   * @param[in] delay   Time after which the calibration will be started (in 0.25 s units).
   * @param[in] handler NULL or user function to be called when calibration is completed or aborted.
   *
   * @retval NRF_SUCCESS             If the procedure was successful.
   * @retval NRF_ERROR_FORBIDDEN     If a SoftDevice is present or the selected LFCLK source is not an RC oscillator.
   * @retval NRF_ERROR_INVALID_STATE If the low-frequency clock is off.
   * @retval NRF_ERROR_BUSY          If calibration is in progress.
   */
  ret_code_t nrf_drv_clock_calibration_start(uint8_t delay, nrf_drv_clock_event_handler_t handler);
  
  /**
   * @brief Function for aborting calibration.
   *
   * This function aborts on-going calibration. If calibration was started, it cannot be stopped. If a handler
   * was provided by @ref nrf_drv_clock_calibration_start, this handler will be called once
   * aborted calibration is completed. @ref nrf_drv_clock_is_calibrating can also be used to check
   * if the system is calibrating.
   *
   * @retval NRF_SUCCESS         If the procedure was successful.
   * @retval NRF_ERROR_FORBIDDEN If a SoftDevice is present or the selected LFCLK source is not an RC oscillator.
   */
  ret_code_t nrf_drv_clock_calibration_abort(void);
  
  /**
   * @brief Function for checking if calibration is in progress.
   *
   * This function indicates that the system is
   * in calibration if it is in any of the calibration process phases (see @ref nrf_drv_clock_calibration_start).
   *
   * @param[out] p_is_calibrating True if calibration is in progress, false if not.
   *
   * @retval NRF_SUCCESS         If the procedure was successful.
   * @retval NRF_ERROR_FORBIDDEN If a SoftDevice is present or the selected LFCLK source is not an RC oscillator.
   */
  ret_code_t nrf_drv_clock_is_calibrating(bool * p_is_calibrating);
  
  /**@brief Function for returning a requested task address for the clock driver module.
   *
   * @param[in] task One of the peripheral tasks.
   *
   * @return Task address.
   */
  __STATIC_INLINE uint32_t nrf_drv_clock_ppi_task_addr(nrf_clock_task_t task);
  
  /**@brief Function for returning a requested event address for the clock driver module.
   *
   * @param[in] event One of the peripheral events.
   *
   * @return Event address.
   */
  __STATIC_INLINE uint32_t nrf_drv_clock_ppi_event_addr(nrf_clock_event_t event);
  
  
  #ifdef SOFTDEVICE_PRESENT
  /**
   * @brief Function called by the SoftDevice handler if an @ref NRF_SOC_EVTS event is received from the SoftDevice.
   *
   * @param[in] evt_id One of NRF_SOC_EVTS values.
   */
  void nrf_drv_clock_on_soc_event(uint32_t evt_id);
  
  /**
   * @brief Function called by the SoftDevice handler when the SoftDevice has been enabled.
   *
   * This function is called just after the SoftDevice has been properly enabled.
   * Its main purpose is to mark that LFCLK has been requested by SD.
   */
  void nrf_drv_clock_on_sd_enable(void);
  
  /**
   * @brief Function called by the SoftDevice handler when the SoftDevice has been disabled.
   *
   * This function is called just after the SoftDevice has been properly disabled.
   * It has two purposes:
   * 1. Releases the LFCLK from the SD.
   * 2. Reinitializes an interrupt after the SD releases POWER_CLOCK_IRQ.
   */
  void nrf_drv_clock_on_sd_disable(void);
  
  #endif
  /**
   *@}
   **/
  
  #ifndef SUPPRESS_INLINE_IMPLEMENTATION
  __STATIC_INLINE uint32_t nrf_drv_clock_ppi_task_addr(nrf_clock_task_t task)
  {
      return nrf_clock_task_address_get(task);
  }
  
  __STATIC_INLINE uint32_t nrf_drv_clock_ppi_event_addr(nrf_clock_event_t event)
  {
      return nrf_clock_event_address_get(event);
  }
  #endif //SUPPRESS_INLINE_IMPLEMENTATION
  
  #ifdef __cplusplus
  }
  #endif
  
  #endif // NRF_DRV_CLOCK_H__
  