/*
    Copyright (C) 2015 Stephen Caudle

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

        http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.
*/

/**
 * @file    SPIv1/hal_spi_lld.h
 * @brief   NRF5 low level SPI driver header.
 *
 * @addtogroup SPI
 * @{
 */

#ifndef HAL_SPI_LLD_H
#define HAL_SPI_LLD_H

#if HAL_USE_SPI || defined(__DOXYGEN__)

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

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

/**
 * @brief   SPI0 interrupt priority level setting.
 */
#if !defined(NRF5_SPI_SPI0_IRQ_PRIORITY) || defined(__DOXYGEN__)
#define NRF5_SPI_SPI0_IRQ_PRIORITY    3
#endif

/**
 * @brief   SPI1 interrupt priority level setting.
 */
#if !defined(NRF5_SPI_SPI1_IRQ_PRIORITY) || defined(__DOXYGEN__)
#define NRF5_SPI_SPI1_IRQ_PRIORITY    3
#endif

/**
 * @brief   Overflow error hook.
 * @details The default action is to stop the system.
 */
#if !defined(NRF5_SPI_SPI_ERROR_HOOK) || defined(__DOXYGEN__)
#define NRF5_SPI_SPI_ERROR_HOOK()    chSysHalt()
#endif

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

#if !NRF5_SPI_USE_SPI0 && !NRF5_SPI_USE_SPI1
#error "SPI driver activated but no SPI peripheral assigned"
#endif

#if NRF5_SPI_USE_SPI0 &&						    \
    !OSAL_IRQ_IS_VALID_PRIORITY(NRF5_SPI_SPI0_IRQ_PRIORITY)
#error "Invalid IRQ priority assigned to SPI0"
#endif

#if NRF5_SPI_USE_SPI1 &&						    \
    !OSAL_IRQ_IS_VALID_PRIORITY(NRF5_SPI_SPI1_IRQ_PRIORITY)
#error "Invalid IRQ priority assigned to SPI1"
#endif

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

/**
 * @brief   SPI frequency
 */
typedef enum {
  NRF5_SPI_FREQ_125KBPS = (SPI_FREQUENCY_FREQUENCY_K125 << SPI_FREQUENCY_FREQUENCY_Pos),
  NRF5_SPI_FREQ_250KBPS = (SPI_FREQUENCY_FREQUENCY_K250 << SPI_FREQUENCY_FREQUENCY_Pos),
  NRF5_SPI_FREQ_500KBPS = (SPI_FREQUENCY_FREQUENCY_K500 << SPI_FREQUENCY_FREQUENCY_Pos),
  NRF5_SPI_FREQ_1MBPS = (SPI_FREQUENCY_FREQUENCY_M1 << SPI_FREQUENCY_FREQUENCY_Pos),
  NRF5_SPI_FREQ_2MBPS = (SPI_FREQUENCY_FREQUENCY_M2 << SPI_FREQUENCY_FREQUENCY_Pos),
  NRF5_SPI_FREQ_4MBPS = (SPI_FREQUENCY_FREQUENCY_M4 << SPI_FREQUENCY_FREQUENCY_Pos),
  NRF5_SPI_FREQ_8MBPS = (SPI_FREQUENCY_FREQUENCY_M8 << SPI_FREQUENCY_FREQUENCY_Pos),
} spifreq_t;

/**
 * @brief   Low level fields of the SPI configuration structure.
 */
#define spi_lld_config_fields                                               \
  /* @brief The frequency of the SPI peripheral */                          \
  spifreq_t             freq;                                               \
  /* @brief The SCK pad */                                                  \
  uint16_t              sckpad;                                             \
  /* @brief The MOSI pad */                                                 \
  uint16_t              mosipad;                                            \
  /* @brief The MOSI pad */                                                 \
  uint16_t              misopad;                                            \
  /* @brief Shift out least significant bit first */                        \
  uint8_t               lsbfirst;                                           \
  /* @brief SPI mode */                                                     \
  uint8_t               mode;                                               \

/**
 * @brief   Low level fields of the SPI driver structure.
 */
#define spi_lld_driver_fields                                               \
  /* @brief Pointer to the SPI port. */                                     \
  NRF_SPI_Type          *port;                                              \
  /* @brief Number of bytes yet to be received. */                          \
  uint32_t              rxcnt;                                              \
  /* @brief Receive pointer or @p NULL. */                                  \
  void                  *rxptr;                                             \
  /* @brief Number of bytes yet to be transmitted. */                       \
  uint32_t              txcnt;                                              \
  /* @brief Transmit pointer or @p NULL. */                                 \
  const void            *txptr;

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

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

#if NRF5_SPI_USE_SPI0 && !defined(__DOXYGEN__)
extern SPIDriver SPID1;
#endif
#if NRF5_SPI_USE_SPI1 && !defined(__DOXYGEN__)
extern SPIDriver SPID2;
#endif

#ifdef __cplusplus
extern "C" {
#endif
  void spi_lld_init(void);
  void spi_lld_start(SPIDriver *spip);
  void spi_lld_stop(SPIDriver *spip);
  void spi_lld_select(SPIDriver *spip);
  void spi_lld_unselect(SPIDriver *spip);
  void spi_lld_ignore(SPIDriver *spip, size_t n);
  void spi_lld_exchange(SPIDriver *spip, size_t n,
                        const void *txbuf, void *rxbuf);
  void spi_lld_send(SPIDriver *spip, size_t n, const void *txbuf);
  void spi_lld_receive(SPIDriver *spip, size_t n, void *rxbuf);
  uint16_t spi_lld_polled_exchange(SPIDriver *spip, uint16_t frame);
#ifdef __cplusplus
}
#endif

#endif /* HAL_USE_SPI */

#endif /* HAL_SPI_LLD_H */

/** @} */