/*
 * Copyright (c) 2010 by Cristian Maglie <c.maglie@arduino.cc>
 * Copyright (c) 2014 by Paul Stoffregen <paul@pjrc.com> (Transaction API)
 * Copyright (c) 2014 by Matthijs Kooijman <matthijs@stdin.nl> (SPISettings AVR)
 * Copyright (c) 2014 by Andrew J. Kroll <xxxajk@gmail.com> (atomicity fixes)
 * SPI Master library for arduino.
 *
 * This file is free software; you can redistribute it and/or modify
 * it under the terms of either the GNU General Public License version 2
 * or the GNU Lesser General Public License version 2.1, both as
 * published by the Free Software Foundation.
 */

#ifndef _SPI_H_INCLUDED
#define _SPI_H_INCLUDED

#include <Arduino.h>
#include "mik32_hal_spi.h"

// SPI_HAS_TRANSACTION means SPI has beginTransaction(), endTransaction(),
// usingInterrupt(), and SPISetting(clock, bitOrder, dataMode)
#define SPI_HAS_TRANSACTION         1

// SPI_HAS_NOTUSINGINTERRUPT means that SPI has notUsingInterrupt() method
#define SPI_HAS_NOTUSINGINTERRUPT   1

// SPI_ATOMIC_VERSION means that SPI has atomicity fixes and what version.
// This way when there is a bug fix you can check this define to alert users
// of your code if it uses better version of this library.
// This also implies everything that SPI_HAS_TRANSACTION as documented above is
// available too.
#define SPI_ATOMIC_VERSION          1

#define SPI_DEFAULT_SPEED   4000000

#ifndef LSBFIRST
#define LSBFIRST 0
#endif
#ifndef MSBFIRST
#define MSBFIRST 1
#endif

// dividers for setClockDivider()
#define SPI_CLOCK_DIV4    0x01    // 8 MHz
#define SPI_CLOCK_DIV8    0x02    // 4 MHz
#define SPI_CLOCK_DIV16   0x03    // 2 MHz
#define SPI_CLOCK_DIV32   0x04    // 1 MHz
#define SPI_CLOCK_DIV64   0x05    // 500 kHz
#define SPI_CLOCK_DIV128  0x06    // 250 kHz
#define SPI_CLOCK_DIV256  0x07    // 125 kHz

// mode[1] - polarity, mode[0] - phase
#define SPI_MODE0         0b00
#define SPI_MODE1         0b01
#define SPI_MODE2         0b10
#define SPI_MODE3         0b11


class SPISettings 
{
public:
  SPISettings(uint32_t speedMaximum, uint8_t dataOrder, uint8_t dataMode) 
  {
    spiUpdateSettings(speedMaximum, dataOrder, dataMode);
  }

  SPISettings() 
  {
    spiUpdateSettings(SPI_DEFAULT_SPEED, MSBFIRST, SPI_MODE0);
  }

private:
  void spiUpdateSettings(uint32_t speedMaximum, uint8_t dataOrder, uint8_t dataMode);

  friend class SPIClass; 
};


class SPIClass 
{
private:
  static bool spiInUse;
  static uint8_t interruptMode; // 0=none, 1=mask
  static uint8_t interruptMask; // which interrupts to mask

public:
  // Initialize the SPI library
  static void begin();

  // If SPI is used from within an interrupt, this function registers
  // that interrupt with the SPI library, so beginTransaction() can
  // prevent conflicts.  The input interruptNumber is the number used
  // with attachInterrupt.
  static void usingInterrupt(uint8_t interruptNumber);
  // And this does the opposite.
  static void notUsingInterrupt(uint8_t interruptNumber);
  // Note: the usingInterrupt and notUsingInterrupt functions should
  // not to be called from ISR context or inside a transaction.
  // For details see:
  // https://github.com/arduino/Arduino/pull/2381
  // https://github.com/arduino/Arduino/pull/2449

  // Before using SPI.transfer() or asserting chip select pins,
  // this function is used to gain exclusive access to the SPI bus
  // and configure the correct settings.
  void beginTransaction(SPISettings settings);

  // Write to the SPI bus (MOSI pin) and also receive (MISO pin)
  uint8_t   transfer(uint8_t data);
  uint16_t  transfer16(uint16_t data);
  void      transfer(void *buf, size_t count);
  
  // After performing a group of transfers and releasing the chip select
  // signal, this function allows others to access the SPI bus
  void endTransaction(void);

  // Disable the SPI bus
  static void end();

  // This function is deprecated.  New applications should use
  // beginTransaction() to configure SPI settings.
  void setBitOrder(uint8_t bitOrder);

  // This function is deprecated.  New applications should use
  // beginTransaction() to configure SPI settings.
  void setDataMode(uint8_t dataMode);
  // This function is deprecated.  New applications should use
  // beginTransaction() to configure SPI settings.
  void setClockDivider(uint8_t clockDiv);

  // A temporary function until this error is fixed in the HAL library
  HAL_StatusTypeDef exchange(SPI_HandleTypeDef *hspi, uint8_t TransmitBytes[], uint8_t ReceiveBytes[], uint32_t DataSize, uint32_t Timeout);
};

extern SPIClass SPI;

#endif