text: /*
   * Copyright (c) 2015 - 2021, Nordic Semiconductor ASA
   * All rights reserved.
   *
   * SPDX-License-Identifier: BSD-3-Clause
   *
   * 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. Neither the name of the copyright holder nor the names of its
   *    contributors may be used to endorse or promote products derived from this
   *    software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER 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 NRFX_QDEC_H__
  #define NRFX_QDEC_H__
  
  #include <nrfx.h>
  #include <hal/nrf_qdec.h>
  
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  /**
   * @defgroup nrfx_qdec QDEC driver
   * @{
   * @ingroup nrf_qdec
   * @brief   Quadrature Decoder (QDEC) peripheral driver.
   */
  
  /** @brief QDEC configuration structure. */
  typedef struct
  {
      nrf_qdec_reportper_t reportper;          /**< Report period in samples. */
      nrf_qdec_sampleper_t sampleper;          /**< Sampling period in microseconds. */
      uint32_t             psela;              /**< Pin number for A input. */
      uint32_t             pselb;              /**< Pin number for B input. */
      uint32_t             pselled;            /**< Pin number for LED output. */
      uint32_t             ledpre;             /**< Time (in microseconds) how long LED is switched on before sampling. */
      nrf_qdec_ledpol_t    ledpol;             /**< Active LED polarity. */
      bool                 dbfen;              /**< State of debouncing filter. */
      bool                 sample_inten;       /**< Enabling sample ready interrupt. */
      uint8_t              interrupt_priority; /**< QDEC interrupt priority. */
  } nrfx_qdec_config_t;
  
  /**
   * @brief QDEC driver default configuration.
   *
   * This configuration sets up QDEC with the following options:
   * - report period: 10 samples
   * - sampling period: 16384 us
   * - LED enabled for 500 us before sampling
   * - LED polarity: active high
   * - debouncing filter disabled
   * - sample ready interrupt disabled
   *
   * @param[in] _pin_a   Pin for A encoder channel input.
   * @param[in] _pin_b   Pin for B encoder channel input.
   * @param[in] _pin_led Pin for LED output.
   */
  #define NRFX_QDEC_DEFAULT_CONFIG(_pin_a, _pin_b, _pin_led)           \
      {                                                                \
          .reportper          = NRF_QDEC_REPORTPER_10,                 \
          .sampleper          = NRF_QDEC_SAMPLEPER_16384us,            \
          .psela              = _pin_a,                                \
          .pselb              = _pin_b,                                \
          .pselled            = _pin_led,                              \
          .ledpre             = 500,                                   \
          .ledpol             = NRF_QDEC_LEPOL_ACTIVE_HIGH,            \
          .dbfen              = NRF_QDEC_DBFEN_DISABLE,                \
          .sample_inten       = false,                                 \
          .interrupt_priority = NRFX_QDEC_DEFAULT_CONFIG_IRQ_PRIORITY  \
      }
  
  /** @brief QDEC sample event data. */
  typedef struct
  {
      int8_t value; /**< Sample value. */
  } nrfx_qdec_sample_data_evt_t;
  
  /** @brief QDEC report event data. */
  typedef struct
  {
      int16_t acc;     /**< Accumulated transitions. */
      uint16_t accdbl; /**< Accumulated double transitions. */
  } nrfx_qdec_report_data_evt_t;
  
  /** @brief QDEC event handler structure. */
  typedef struct
  {
      nrf_qdec_event_t  type; /**< Event type. */
      union
      {
          nrfx_qdec_sample_data_evt_t sample; /**< Sample event data. */
          nrfx_qdec_report_data_evt_t report; /**< Report event data. */
      } data;                                 /**< Union to store event data. */
  } nrfx_qdec_event_t;
  
  /**
   * @brief QDEC event handler.
   *
   * @param[in] event QDEC event structure.
   */
  typedef void (*nrfx_qdec_event_handler_t)(nrfx_qdec_event_t event);
  
  /**
   * @brief Function for initializing QDEC.
   *
   * @param[in] p_config      Pointer to the structure with the initial configuration.
   * @param[in] event_handler Event handler provided by the user.
   *                          Must not be NULL.
   *
   * @retval NRFX_SUCCESS             Initialization was successful.
   * @retval NRFX_ERROR_INVALID_STATE The QDEC was already initialized.
   */
  nrfx_err_t nrfx_qdec_init(nrfx_qdec_config_t const * p_config,
                            nrfx_qdec_event_handler_t  event_handler);
  
  /**
   * @brief Function for uninitializing QDEC.
   *
   * @note Function asserts if module is uninitialized.
   */
  void nrfx_qdec_uninit(void);
  
  /**
   * @brief Function for enabling QDEC.
   *
   * @note Function asserts if module is uninitialized or enabled.
   */
  void nrfx_qdec_enable(void);
  
  /**
   * @brief Function for disabling QDEC.
   *
   * @note Function asserts if module is uninitialized or disabled.
   */
  void nrfx_qdec_disable(void);
  
  /**
   * @brief Function for reading accumulated transitions from the QDEC peripheral.
   *
   * @note Function asserts if module is not enabled.
   * @note Accumulators are cleared after reading.
   *
   * @param[out] p_acc    Pointer to store the accumulated transitions.
   * @param[out] p_accdbl Pointer to store the accumulated double transitions.
   */
  void nrfx_qdec_accumulators_read(int16_t * p_acc, int16_t * p_accdbl);
  
  /**
   * @brief Function for returning the address of the specified QDEC task.
   *
   * @param task QDEC task.
   *
   * @return Task address.
   */
  NRFX_STATIC_INLINE uint32_t nrfx_qdec_task_address_get(nrf_qdec_task_t task);
  
  /**
   * @brief Function for returning the address of the specified QDEC event.
   *
   * @param event QDEC event.
   *
   * @return Event address.
   */
  NRFX_STATIC_INLINE uint32_t nrfx_qdec_event_address_get(nrf_qdec_event_t event);
  
  #ifndef NRFX_DECLARE_ONLY
  NRFX_STATIC_INLINE uint32_t nrfx_qdec_task_address_get(nrf_qdec_task_t task)
  {
      return nrf_qdec_task_address_get(NRF_QDEC, task);
  }
  
  NRFX_STATIC_INLINE uint32_t nrfx_qdec_event_address_get(nrf_qdec_event_t event)
  {
      return nrf_qdec_event_address_get(NRF_QDEC, event);
  }
  #endif // NRFX_DECLARE_ONLY
  
  /** @} */
  
  
  void nrfx_qdec_irq_handler(void);
  
  
  #ifdef __cplusplus
  }
  #endif
  
  #endif // NRFX_QDEC_H__
  