bmp.c

/***************************************************************************/
#include <stdint.h>
#include <stdbool.h>
#include <stdlib.h>

#include "thunderboard/bmp.h"
#include "thunderboard/board.h"
#include "thunderboard/util.h"
#include "i2cspm.h"

#include "thunderboard/bosch/BMP280_Driver/bmp280.h"

/***************************************************************************/
/****************************************************************************/
/* Local Function Prototypes                                                */
/****************************************************************************/
static int8_t  i2cBusRead   ( uint8_t devAddr, uint8_t regAddr, uint8_t *regData, uint8_t count );
static int8_t  i2cBusWrite  ( uint8_t devAddr, uint8_t regAddr, uint8_t *regData, uint8_t count );
static uint8_t readRegister ( uint8_t addr );


/***************************************************************************/
static uint8_t bmpDeviceId;       /* The device ID of the connected chip  */
static uint8_t bmp280PowerMode;   /* The actual power mode of the BMP280  */
static struct  bmp280_t bmp280;   /* Structure to hold BMP280 driver data */

/***************************************************************************/
/***************************************************************************/
uint32_t BMP_init( uint8_t *deviceId )
{

   int result;

   /* Enable power to the enviromental sensor group */
   BOARD_envSensEnable( true );

   /* The device needs 2 ms startup time */
   UTIL_delay( 2 );

   /* Read device ID to determine if we have a BMP280 connected */
   bmpDeviceId = readRegister( BMP_REG_ADDR_ID );

   if( bmpDeviceId != BMP_DEVICE_ID_BMP280 ) {
      return BMP_ERROR_DEVICE_ID_MISMATCH;
   }

   bmp280.bus_write  = i2cBusWrite;
   bmp280.bus_read   = i2cBusRead;
   bmp280.dev_addr   = BMP_I2C_BUS_ADDRESS;
   bmp280.delay_msec = UTIL_delay;

   result = bmp280_init( &bmp280 );

   if( result != BMP_OK ) {
      return result;
   }

   result = bmp280_set_power_mode( BMP280_FORCED_MODE );

   if( result != BMP_OK ) {
      return result;
   }

   result = bmp280_set_work_mode( BMP280_ULTRA_HIGH_RESOLUTION_MODE );

   if( result != BMP_OK ) {
      return result;
   }

   bmp280PowerMode = BMP280_FORCED_MODE;

   *deviceId = bmpDeviceId;

   return BMP_OK;

}

/***************************************************************************/
void BMP_deInit( void )
{
   bmp280_set_power_mode( BMP280_SLEEP_MODE );
   return;
}

/***************************************************************************/
uint32_t BMP_config( BMP_Config *cfg )
{

   uint32_t result;

   result = 0;

   result += bmp280_set_work_mode( cfg->oversampling );
   result += bmp280_set_power_mode( cfg->powerMode );
   bmp280PowerMode = cfg->powerMode;
   result += bmp280_set_standby_durn( cfg->standbyTime );

   return result;

}

/***************************************************************************/
uint32_t BMP_getTemperature( float *temperature )
{

   int8_t result;
   int32_t uncompTemp;
   int32_t uncompPressure;
   int32_t compTemp;

   if( bmp280PowerMode == BMP280_NORMAL_MODE ) {
      result = bmp280_read_uncomp_temperature( &uncompTemp );
   }
   else {
      result = bmp280_get_forced_uncomp_pressure_temperature( &uncompPressure, &uncompTemp );
   }

   if( result != SUCCESS ) {
      return (uint32_t) result;
   }

   compTemp = bmp280_compensate_temperature_int32( uncompTemp );
   *temperature = (float) compTemp;
   *temperature /= 100.0f;

   return BMP_OK;

}

/***************************************************************************/
uint32_t BMP_getPressure( float *pressure )
{

   int8_t result;
   int32_t uncompTemp;
   int32_t uncompPressure;
   uint32_t compPressure;

   if( bmp280PowerMode == BMP280_NORMAL_MODE ) {
      result = bmp280_read_uncomp_pressure( &uncompPressure );
      if( result == SUCCESS ){
         result = bmp280_read_uncomp_temperature( &uncompTemp );
      }
   }
   else {
      result = bmp280_get_forced_uncomp_pressure_temperature( &uncompPressure, &uncompTemp );
   }

   if( result != SUCCESS ) {
      return (uint32_t) result;
   }
  
   bmp280_compensate_temperature_int32( uncompTemp );
   compPressure = bmp280_compensate_pressure_int64( uncompPressure );
   
   *pressure = (float) compPressure;
   *pressure /= 256.0f;
   *pressure /= 100.0f;
   
   return BMP_OK;

}

/***************************************************************************/
static uint8_t readRegister( uint8_t addr )
{

   I2C_TransferSeq_TypeDef seq;
   I2C_TransferReturn_TypeDef ret;
   uint8_t reg;

   seq.addr = BMP_I2C_BUS_ADDRESS << 1;
   seq.flags = I2C_FLAG_WRITE_READ;

   seq.buf[0].len  = 1;
   seq.buf[0].data = &addr;
   seq.buf[1].len  = 1;
   seq.buf[1].data = &reg;

   ret = I2CSPM_Transfer( BMP_I2C_DEVICE, &seq );

   if( ret != i2cTransferDone ) {
      return 0;
   }

   return reg;

}

/***************************************************************************/
static int8_t i2cBusWrite( uint8_t devAddr, uint8_t regAddr, uint8_t *regData, uint8_t count )
{

   I2C_TransferSeq_TypeDef seq;
   I2C_TransferReturn_TypeDef ret;

   seq.addr = devAddr << 1;
   seq.flags = I2C_FLAG_WRITE_WRITE;

   seq.buf[0].len  = 1;
   seq.buf[0].data = &regAddr;
   seq.buf[1].len  = count;
   seq.buf[1].data = regData;

   ret = I2CSPM_Transfer( BMP_I2C_DEVICE, &seq );

   if( ret != i2cTransferDone ) {
      return BMP_ERROR_I2C_TRANSACTION_FAILED;
   }

   return BMP_OK;

}

/***************************************************************************/
static int8_t i2cBusRead( uint8_t devAddr, uint8_t regAddr, uint8_t *regData, uint8_t count )
{

   I2C_TransferSeq_TypeDef seq;
   I2C_TransferReturn_TypeDef ret;

   seq.addr = devAddr << 1;
   seq.flags = I2C_FLAG_WRITE_READ;

   seq.buf[0].len  = 1;
   seq.buf[0].data = &regAddr;
   seq.buf[1].len  = count;
   seq.buf[1].data = regData;

   ret = I2CSPM_Transfer( BMP_I2C_DEVICE, &seq );

   if( ret != i2cTransferDone ) {
      return BMP_ERROR_I2C_TRANSACTION_FAILED;
   }

   return BMP_OK;

}