#include <stdbool.h>
#include "efm32.h"
#include "efm32_chip.h"
#include "efm32_i2c.h"
#include "efm32_rtc.h"
#include "efm32_cmu.h"
#include "efm32_emu.h"
#include "efm32_gpio.h"
#include "mag3110.h"
#include "i2c.h"
#include "main_program.h"


/**************************************************************************//**
 * @brief  Setup I2C
 *****************************************************************************/
void setupI2C(void)
{
     // Using default settings
  I2C_Init_TypeDef i2cInit = I2C_INIT_DEFAULT;
  
      /* Enable GPIO clock */
    CMU->HFPERCLKEN0 |= CMU_HFPERCLKEN0_GPIO;
   
   /* Using PA0 (SDA) and PA1 (SCL) */
  GPIO_PinModeSet(gpioPortA, 1, gpioModeWiredAndPullUpFilter, 1);
  GPIO_PinModeSet(gpioPortA, 0, gpioModeWiredAndPullUpFilter, 1);
  
    /* Enable clock for I2C0 */
   CMU->HFPERCLKEN0 |= CMU_HFPERCLKEN0_I2C0;
   
  /* Enable pins at location 1 */
  I2C0->ROUTE = I2C_ROUTE_SDAPEN |  I2C_ROUTE_SCLPEN;

  /* Initializing the I2C */
  I2C_Init(I2C0, &i2cInit);
   
}

/***************************************************************************//**
 * @brief
 *   Perform I2C transfer.
 *
 * @details
 *   This driver only supports master mode, single bus-master. It does not
 *   return until the transfer is complete, polling for completion.
 *
 * @param[in] seq
 *   Pointer to sequence structure defining the I2C transfer to take place. The
 *   referenced structure must exist until the transfer has fully completed.
 ******************************************************************************/
I2C_TransferReturn_TypeDef I2CDRV_Transfer(I2C_TransferSeq_TypeDef *seq)
{
  I2C_TransferReturn_TypeDef ret;

  /* Do a polled transfer */
  ret = I2C_TransferInit(I2C0, seq);
  while (ret == i2cTransferInProgress)
  {
    ret = I2C_Transfer(I2C0);
  }

  return(ret);
}


/***************************************************************************//**
 * @brief
 *   Read sensor register content.
 * @param[in] i2c
 *   Pointer to I2C peripheral register block.
 *
 * @param[in] addr
 *   I2C address for the sensor, in 8 bit format, where LSB is reserved for R/W bit.
 *
 * @param[in] reg
 *   Register to read.
 *
 * @param[out] val
 *   Reference to place register read.
 *
 * @return
 *   Returns 0 if register read, <0 if unable to read register.
 ******************************************************************************/

int I2C_Read_reg(I2C_TypeDef *i2c, uint8_t addr, uint16_t reg, uint16_t *val)
{
  I2C_TransferSeq_TypeDef seq;
  I2C_TransferReturn_TypeDef ret;
  uint8_t regid[1];
  uint8_t data[2];

  seq.addr = addr;
  seq.flags = I2C_FLAG_WRITE_READ;
  
  /* Select register to be read */
  regid[0] = ((uint8_t)reg); 
  
  seq.buf[0].data = regid;
  seq.buf[0].len = 1;
  
  /* Select location/length to place register */
  
     /* Only 1 byte reg, clear upper 8 bits */
    data[0] = 0;
    seq.buf[1].data = data + 1;
    seq.buf[1].len = 1;
 
  
  ret = I2CDRV_Transfer(&seq);
  if (ret != i2cTransferDone)
  {
    return((int)ret);
  }

  *val = (((uint16_t)(data[0])) << 8) | data[1];

 return(0);
   
  
}


/***************************************************************************//**
 * @brief
 *   Write to sensor register.
 *
 * @param[in] i2c
 *   Pointer to I2C peripheral register block.
 *
 * @param[in] addr
 *   I2C address for the sensor, in 8 bit format, where LSB is reserved
 *   for R/W bit.
 *
 * @param[in] reg
 *   Register to write.
 *
 * @param[in] val
 *   Value used when writing to register.
 *
 * @return
 *   Returns 0 if register written, <0 if unable to write to register.
 ******************************************************************************/
int I2C_Write_reg(I2C_TypeDef *i2c, uint8_t addr, uint16_t reg, uint16_t val)
{
  I2C_TransferSeq_TypeDef seq;
  I2C_TransferReturn_TypeDef ret;
  uint8_t data[3];

  seq.addr = addr;
  seq.flags = I2C_FLAG_WRITE;
  
  /* Select register to be written */
  data[0] = ((uint8_t)reg) ;
  seq.buf[0].data = data;


    /* Only 1 byte reg */
    data[1] = (uint8_t)val;
    seq.buf[0].len = 2;
  

  ret = I2CDRV_Transfer(&seq);
  if (ret != i2cTransferDone)
  {
    return((int)ret);
  }

  return(ret);
}