text: /*
   * Copyright (c) 2015 - 2018, Nordic Semiconductor ASA
   * All rights reserved.
   *
   * 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 NRF_TWIM_H__
  #define NRF_TWIM_H__
  
  #include <nrfx.h>
  
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  /**
   * @defgroup nrf_twim_hal TWIM HAL
   * @{
   * @ingroup nrf_twim
   * @brief   Hardware access layer for managing the TWIM peripheral.
   */
  
  /**
   * @brief TWIM tasks.
   */
  typedef enum
  {
      /*lint -save -e30*/
      NRF_TWIM_TASK_STARTRX = offsetof(NRF_TWIM_Type, TASKS_STARTRX), ///< Start TWI receive sequence.
      NRF_TWIM_TASK_STARTTX = offsetof(NRF_TWIM_Type, TASKS_STARTTX), ///< Start TWI transmit sequence.
      NRF_TWIM_TASK_STOP    = offsetof(NRF_TWIM_Type, TASKS_STOP),    ///< Stop TWI transaction.
      NRF_TWIM_TASK_SUSPEND = offsetof(NRF_TWIM_Type, TASKS_SUSPEND), ///< Suspend TWI transaction.
      NRF_TWIM_TASK_RESUME  = offsetof(NRF_TWIM_Type, TASKS_RESUME)   ///< Resume TWI transaction.
      /*lint -restore*/
  } nrf_twim_task_t;
  
  /**
   * @brief TWIM events.
   */
  typedef enum
  {
      /*lint -save -e30*/
      NRF_TWIM_EVENT_STOPPED   = offsetof(NRF_TWIM_Type, EVENTS_STOPPED),   ///< TWI stopped.
      NRF_TWIM_EVENT_ERROR     = offsetof(NRF_TWIM_Type, EVENTS_ERROR),     ///< TWI error.
      NRF_TWIM_EVENT_SUSPENDED = 0x148,                                     ///< TWI suspended.
      NRF_TWIM_EVENT_RXSTARTED = offsetof(NRF_TWIM_Type, EVENTS_RXSTARTED), ///< Receive sequence started.
      NRF_TWIM_EVENT_TXSTARTED = offsetof(NRF_TWIM_Type, EVENTS_TXSTARTED), ///< Transmit sequence started.
      NRF_TWIM_EVENT_LASTRX    = offsetof(NRF_TWIM_Type, EVENTS_LASTRX),    ///< Byte boundary, starting to receive the last byte.
      NRF_TWIM_EVENT_LASTTX    = offsetof(NRF_TWIM_Type, EVENTS_LASTTX)     ///< Byte boundary, starting to transmit the last byte.
      /*lint -restore*/
  } nrf_twim_event_t;
  
  /**
   * @brief TWIM shortcuts.
   */
  typedef enum
  {
      NRF_TWIM_SHORT_LASTTX_STARTRX_MASK = TWIM_SHORTS_LASTTX_STARTRX_Msk,  ///< Shortcut between LASTTX event and STARTRX task.
      NRF_TWIM_SHORT_LASTTX_SUSPEND_MASK = TWIM_SHORTS_LASTTX_SUSPEND_Msk,  ///< Shortcut between LASTTX event and SUSPEND task.
      NRF_TWIM_SHORT_LASTTX_STOP_MASK    = TWIM_SHORTS_LASTTX_STOP_Msk,     ///< Shortcut between LASTTX event and STOP task.
      NRF_TWIM_SHORT_LASTRX_STARTTX_MASK = TWIM_SHORTS_LASTRX_STARTTX_Msk,  ///< Shortcut between LASTRX event and STARTTX task.
      NRF_TWIM_SHORT_LASTRX_STOP_MASK    = TWIM_SHORTS_LASTRX_STOP_Msk,     ///< Shortcut between LASTRX event and STOP task.
      NRF_TWIM_ALL_SHORTS_MASK           = TWIM_SHORTS_LASTTX_STARTRX_Msk |
                                           TWIM_SHORTS_LASTTX_SUSPEND_Msk |
                                           TWIM_SHORTS_LASTTX_STOP_Msk    |
                                           TWIM_SHORTS_LASTRX_STARTTX_Msk |
                                           TWIM_SHORTS_LASTRX_STOP_Msk      ///< All TWIM shortcuts.
  } nrf_twim_short_mask_t;
  
  /**
   * @brief TWIM interrupts.
   */
  typedef enum
  {
      NRF_TWIM_INT_STOPPED_MASK   = TWIM_INTENSET_STOPPED_Msk,   ///< Interrupt on STOPPED event.
      NRF_TWIM_INT_ERROR_MASK     = TWIM_INTENSET_ERROR_Msk,     ///< Interrupt on ERROR event.
      NRF_TWIM_INT_SUSPENDED_MASK = TWIM_INTENSET_SUSPENDED_Msk, ///< Interrupt on SUSPENDED event.
      NRF_TWIM_INT_RXSTARTED_MASK = TWIM_INTENSET_RXSTARTED_Msk, ///< Interrupt on RXSTARTED event.
      NRF_TWIM_INT_TXSTARTED_MASK = TWIM_INTENSET_TXSTARTED_Msk, ///< Interrupt on TXSTARTED event.
      NRF_TWIM_INT_LASTRX_MASK    = TWIM_INTENSET_LASTRX_Msk,    ///< Interrupt on LASTRX event.
      NRF_TWIM_INT_LASTTX_MASK    = TWIM_INTENSET_LASTTX_Msk,     ///< Interrupt on LASTTX event.
      NRF_TWIM_ALL_INTS_MASK      = TWIM_INTENSET_STOPPED_Msk   |
                                    TWIM_INTENSET_ERROR_Msk     |
                                    TWIM_INTENSET_SUSPENDED_Msk |
                                    TWIM_INTENSET_RXSTARTED_Msk |
                                    TWIM_INTENSET_TXSTARTED_Msk |
                                    TWIM_INTENSET_LASTRX_Msk    |
                                    TWIM_INTENSET_LASTTX_Msk      ///< Interrupt on LASTTX event.
  } nrf_twim_int_mask_t;
  
  /**
   * @brief TWIM master clock frequency.
   */
  typedef enum
  {
      NRF_TWIM_FREQ_100K = TWIM_FREQUENCY_FREQUENCY_K100, ///< 100 kbps.
      NRF_TWIM_FREQ_250K = TWIM_FREQUENCY_FREQUENCY_K250, ///< 250 kbps.
      NRF_TWIM_FREQ_400K = TWIM_FREQUENCY_FREQUENCY_K400  ///< 400 kbps.
  } nrf_twim_frequency_t;
  
  /**
   * @brief TWIM error source.
   */
  typedef enum
  {
      NRF_TWIM_ERROR_ADDRESS_NACK = TWIM_ERRORSRC_ANACK_Msk, ///< NACK received after sending the address.
      NRF_TWIM_ERROR_DATA_NACK    = TWIM_ERRORSRC_DNACK_Msk  ///< NACK received after sending a data byte.
  } nrf_twim_error_t;
  
  
  /**
   * @brief Function for activating a specific TWIM task.
   *
   * @param[in] p_reg Pointer to the peripheral registers structure.
   * @param[in] task   Task to activate.
   */
  __STATIC_INLINE void nrf_twim_task_trigger(NRF_TWIM_Type * p_reg,
                                             nrf_twim_task_t task);
  
  /**
   * @brief Function for getting the address of a specific TWIM task register.
   *
   * @param[in] p_reg Pointer to the peripheral registers structure.
   * @param[in] task   Requested task.
   *
   * @return Address of the specified task register.
   */
  __STATIC_INLINE uint32_t * nrf_twim_task_address_get(NRF_TWIM_Type * p_reg,
                                                       nrf_twim_task_t task);
  
  /**
   * @brief Function for clearing a specific TWIM event.
   *
   * @param[in] p_reg Pointer to the peripheral registers structure.
   * @param[in] event  Event to clear.
   */
  __STATIC_INLINE void nrf_twim_event_clear(NRF_TWIM_Type * p_reg,
                                            nrf_twim_event_t event);
  
  /**
   * @brief Function for checking the state of a specific TWIM event.
   *
   * @param[in] p_reg Pointer to the peripheral registers structure.
   * @param[in] event  Event to check.
   *
   * @retval true  If the event is set.
   * @retval false If the event is not set.
   */
  __STATIC_INLINE bool nrf_twim_event_check(NRF_TWIM_Type * p_reg,
                                            nrf_twim_event_t event);
  
  /**
   * @brief Function for getting the address of a specific TWIM event register.
   *
   * @param[in] p_reg Pointer to the peripheral registers structure.
   * @param[in] event  Requested event.
   *
   * @return Address of the specified event register.
   */
  __STATIC_INLINE uint32_t * nrf_twim_event_address_get(NRF_TWIM_Type  * p_reg,
                                                        nrf_twim_event_t event);
  
  /**
   * @brief Function for enabling specified shortcuts.
   *
   * @param[in] p_reg      Pointer to the peripheral registers structure.
   * @param[in] shorts_mask Shortcuts to enable.
   */
  __STATIC_INLINE void nrf_twim_shorts_enable(NRF_TWIM_Type * p_reg,
                                              uint32_t shorts_mask);
  
  /**
   * @brief Function for disabling specified shortcuts.
   *
   * @param[in] p_reg      Pointer to the peripheral registers structure.
   * @param[in] shorts_mask Shortcuts to disable.
   */
  __STATIC_INLINE void nrf_twim_shorts_disable(NRF_TWIM_Type * p_reg,
                                               uint32_t shorts_mask);
  
  /**
   * @brief Function for enabling specified interrupts.
   *
   * @param[in] p_reg   Pointer to the peripheral registers structure.
   * @param[in] int_mask Interrupts to enable.
   */
  __STATIC_INLINE void nrf_twim_int_enable(NRF_TWIM_Type * p_reg,
                                           uint32_t int_mask);
  
  /**
   * @brief Function for disabling specified interrupts.
   *
   * @param[in] p_reg   Pointer to the peripheral registers structure.
   * @param[in] int_mask Interrupts to disable.
   */
  __STATIC_INLINE void nrf_twim_int_disable(NRF_TWIM_Type * p_reg,
                                            uint32_t int_mask);
  
  /**
   * @brief Function for checking the state of a given interrupt.
   *
   * @param[in] p_reg   Pointer to the peripheral registers structure.
   * @param[in] int_mask Interrupt to check.
   *
   * @retval true  If the interrupt is enabled.
   * @retval false If the interrupt is not enabled.
   */
  __STATIC_INLINE bool nrf_twim_int_enable_check(NRF_TWIM_Type * p_reg,
                                                 nrf_twim_int_mask_t int_mask);
  
  /**
   * @brief Function for enabling the TWIM peripheral.
   *
   * @param[in] p_reg Pointer to the peripheral registers structure.
   */
  __STATIC_INLINE void nrf_twim_enable(NRF_TWIM_Type * p_reg);
  
  /**
   * @brief Function for disabling the TWIM peripheral.
   *
   * @param[in] p_reg Pointer to the peripheral registers structure.
   */
  __STATIC_INLINE void nrf_twim_disable(NRF_TWIM_Type * p_reg);
  
  /**
   * @brief Function for configuring TWI pins.
   *
   *
   * @param[in] p_reg  Pointer to the peripheral registers structure.
   * @param[in] scl_pin SCL pin number.
   * @param[in] sda_pin SDA pin number.
   */
  __STATIC_INLINE void nrf_twim_pins_set(NRF_TWIM_Type * p_reg,
                                         uint32_t scl_pin,
                                         uint32_t sda_pin);
  
  /**
   * @brief Function for setting the TWI master clock frequency.
   *
   * @param[in] p_reg    Pointer to the peripheral registers structure.
   * @param[in] frequency TWI frequency.
   */
  __STATIC_INLINE void nrf_twim_frequency_set(NRF_TWIM_Type * p_reg,
                                              nrf_twim_frequency_t frequency);
  
  /**
   * @brief Function for checking the TWI error source.
   *
   * The error flags are cleared after reading.
   *
   * @param[in] p_reg Pointer to the peripheral registers structure.
   *
   * @return Mask with error source flags.
   */
  __STATIC_INLINE uint32_t nrf_twim_errorsrc_get_and_clear(NRF_TWIM_Type * p_reg);
  
  /**
   * @brief Function for setting the address to be used in TWI transfers.
   *
   * @param[in] p_reg  Pointer to the peripheral registers structure.
   * @param[in] address Address to be used in transfers.
   */
  __STATIC_INLINE void nrf_twim_address_set(NRF_TWIM_Type * p_reg,
                                            uint8_t address);
  
  /**
   * @brief Function for setting the transmit buffer.
   *
   * @param[in]  p_reg   Pointer to the peripheral registers structure.
   * @param[in]  p_buffer Pointer to the buffer with data to send.
   * @param[in]  length   Maximum number of data bytes to transmit.
   */
  __STATIC_INLINE void nrf_twim_tx_buffer_set(NRF_TWIM_Type * p_reg,
                                              uint8_t const * p_buffer,
                                              size_t          length);
  
  /**
   * @brief Function for setting the receive buffer.
   *
   * @param[in] p_reg   Pointer to the peripheral registers structure.
   * @param[in] p_buffer Pointer to the buffer for received data.
   * @param[in] length   Maximum number of data bytes to receive.
   */
  __STATIC_INLINE void nrf_twim_rx_buffer_set(NRF_TWIM_Type * p_reg,
                                              uint8_t * p_buffer,
                                              size_t    length);
  
  __STATIC_INLINE void nrf_twim_shorts_set(NRF_TWIM_Type * p_reg,
                                           uint32_t shorts_mask);
  
  __STATIC_INLINE size_t nrf_twim_txd_amount_get(NRF_TWIM_Type * p_reg);
  
  __STATIC_INLINE size_t nrf_twim_rxd_amount_get(NRF_TWIM_Type * p_reg);
  
  /**
   * @brief Function for enabling the TX list feature.
   *
   * @param[in] p_reg Pointer to the peripheral registers structure.
   */
  __STATIC_INLINE void nrf_twim_tx_list_enable(NRF_TWIM_Type * p_reg);
  
  /**
   * @brief Function for disabling the TX list feature.
   *
   * @param[in] p_reg Pointer to the peripheral registers structure.
   */
  __STATIC_INLINE void nrf_twim_tx_list_disable(NRF_TWIM_Type * p_reg);
  
  /**
   * @brief Function for enabling the RX list feature.
   *
   * @param[in] p_reg Pointer to the peripheral registers structure.
   */
  __STATIC_INLINE void nrf_twim_rx_list_enable(NRF_TWIM_Type * p_reg);
  
  /**
   * @brief Function for disabling the RX list feature.
   *
   * @param[in] p_reg Pointer to the peripheral registers structure.
   */
  __STATIC_INLINE void nrf_twim_rx_list_disable(NRF_TWIM_Type * p_reg);
  
  #ifndef SUPPRESS_INLINE_IMPLEMENTATION
  
  __STATIC_INLINE void nrf_twim_task_trigger(NRF_TWIM_Type * p_reg,
                                             nrf_twim_task_t task)
  {
      *((volatile uint32_t *)((uint8_t *)p_reg + (uint32_t)task)) = 0x1UL;
  }
  
  __STATIC_INLINE uint32_t * nrf_twim_task_address_get(NRF_TWIM_Type * p_reg,
                                                       nrf_twim_task_t task)
  {
      return (uint32_t *)((uint8_t *)p_reg + (uint32_t)task);
  }
  
  __STATIC_INLINE void nrf_twim_event_clear(NRF_TWIM_Type * p_reg,
                                            nrf_twim_event_t event)
  {
      *((volatile uint32_t *)((uint8_t *)p_reg + (uint32_t)event)) = 0x0UL;
  #if __CORTEX_M == 0x04
      volatile uint32_t dummy = *((volatile uint32_t *)((uint8_t *)p_reg + (uint32_t)event));
      (void)dummy;
  #endif
  }
  
  __STATIC_INLINE bool nrf_twim_event_check(NRF_TWIM_Type * p_reg,
                                            nrf_twim_event_t event)
  {
      return (bool)*(volatile uint32_t *)((uint8_t *)p_reg + (uint32_t)event);
  }
  
  __STATIC_INLINE uint32_t * nrf_twim_event_address_get(NRF_TWIM_Type  * p_reg,
                                                        nrf_twim_event_t event)
  {
      return (uint32_t *)((uint8_t *)p_reg + (uint32_t)event);
  }
  
  __STATIC_INLINE void nrf_twim_shorts_enable(NRF_TWIM_Type * p_reg,
                                              uint32_t shorts_mask)
  {
      p_reg->SHORTS |= shorts_mask;
  }
  
  __STATIC_INLINE void nrf_twim_shorts_disable(NRF_TWIM_Type * p_reg,
                                               uint32_t shorts_mask)
  {
      p_reg->SHORTS &= ~(shorts_mask);
  }
  
  __STATIC_INLINE void nrf_twim_int_enable(NRF_TWIM_Type * p_reg,
                                           uint32_t int_mask)
  {
      p_reg->INTENSET = int_mask;
  }
  
  __STATIC_INLINE void nrf_twim_int_disable(NRF_TWIM_Type * p_reg,
                                            uint32_t int_mask)
  {
      p_reg->INTENCLR = int_mask;
  }
  
  __STATIC_INLINE bool nrf_twim_int_enable_check(NRF_TWIM_Type * p_reg,
                                                 nrf_twim_int_mask_t int_mask)
  {
      return (bool)(p_reg->INTENSET & int_mask);
  }
  
  __STATIC_INLINE void nrf_twim_enable(NRF_TWIM_Type * p_reg)
  {
      p_reg->ENABLE = (TWIM_ENABLE_ENABLE_Enabled << TWIM_ENABLE_ENABLE_Pos);
  }
  
  __STATIC_INLINE void nrf_twim_disable(NRF_TWIM_Type * p_reg)
  {
      p_reg->ENABLE = (TWIM_ENABLE_ENABLE_Disabled << TWIM_ENABLE_ENABLE_Pos);
  }
  
  __STATIC_INLINE void nrf_twim_pins_set(NRF_TWIM_Type * p_reg,
                                         uint32_t scl_pin,
                                         uint32_t sda_pin)
  {
      p_reg->PSEL.SCL = scl_pin;
      p_reg->PSEL.SDA = sda_pin;
  }
  
  __STATIC_INLINE void nrf_twim_frequency_set(NRF_TWIM_Type * p_reg,
                                              nrf_twim_frequency_t frequency)
  {
      p_reg->FREQUENCY = frequency;
  }
  
  __STATIC_INLINE uint32_t nrf_twim_errorsrc_get_and_clear(NRF_TWIM_Type * p_reg)
  {
      uint32_t error_source = p_reg->ERRORSRC;
  
      // [error flags are cleared by writing '1' on their position]
      p_reg->ERRORSRC = error_source;
  
      return error_source;
  }
  
  __STATIC_INLINE void nrf_twim_address_set(NRF_TWIM_Type * p_reg,
                                            uint8_t address)
  {
      p_reg->ADDRESS = address;
  }
  
  __STATIC_INLINE void nrf_twim_tx_buffer_set(NRF_TWIM_Type * p_reg,
                                              uint8_t const * p_buffer,
                                              size_t          length)
  {
      p_reg->TXD.PTR    = (uint32_t)p_buffer;
      p_reg->TXD.MAXCNT = length;
  }
  
  __STATIC_INLINE void nrf_twim_rx_buffer_set(NRF_TWIM_Type * p_reg,
                                              uint8_t * p_buffer,
                                              size_t    length)
  {
      p_reg->RXD.PTR    = (uint32_t)p_buffer;
      p_reg->RXD.MAXCNT = length;
  }
  
  __STATIC_INLINE void nrf_twim_shorts_set(NRF_TWIM_Type * p_reg,
                                           uint32_t shorts_mask)
  {
      p_reg->SHORTS = shorts_mask;
  }
  
  __STATIC_INLINE size_t nrf_twim_txd_amount_get(NRF_TWIM_Type * p_reg)
  {
      return p_reg->TXD.AMOUNT;
  }
  
  __STATIC_INLINE size_t nrf_twim_rxd_amount_get(NRF_TWIM_Type * p_reg)
  {
      return p_reg->RXD.AMOUNT;
  }
  
  __STATIC_INLINE void nrf_twim_tx_list_enable(NRF_TWIM_Type * p_reg)
  {
      p_reg->TXD.LIST = 1;
  }
  
  __STATIC_INLINE void nrf_twim_tx_list_disable(NRF_TWIM_Type * p_reg)
  {
      p_reg->TXD.LIST = 0;
  }
  
  __STATIC_INLINE void nrf_twim_rx_list_enable(NRF_TWIM_Type * p_reg)
  {
      p_reg->RXD.LIST = 1;
  }
  
  __STATIC_INLINE void nrf_twim_rx_list_disable(NRF_TWIM_Type * p_reg)
  {
      p_reg->RXD.LIST = 0;
  }
  #endif // SUPPRESS_INLINE_IMPLEMENTATION
  
  /** @} */
  
  #ifdef __cplusplus
  }
  #endif
  
  #endif // NRF_TWIM_H__
  