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/****************************************************************************
 * drivers/sensors/adxl345_i2c.c
 *
 *   Copyright (C) 2014 Alan Carvalho de Assis. All rights reserved.
 *   Author: Alan Carvalho de Assis <acassis@gmail.com>
 *   Based on STME811 driver
 *   Author: Gregory Nutt <gnutt@nuttx.org>
 *
 * 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 NuttX 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 OWNER 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.
 *
 ****************************************************************************/

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <nuttx/config.h>

#include <unistd.h>
#include <errno.h>
#include <debug.h>

#include <nuttx/kmalloc.h>
#include <nuttx/sensors/adxl345.h>

#include "adxl345.h"

#if defined(CONFIG_SENSORS_ADXL345)

/****************************************************************************
 * Name: adxl345_getreg8
 *
 * Description:
 *   Read from an 8-bit ADXL345 register
 *
 ****************************************************************************/

#ifdef CONFIG_ADXL345_I2C
uint8_t adxl345_getreg8(FAR struct adxl345_dev_s *priv, uint8_t regaddr)
{
  /* 8-bit data read sequence:
   *
   *  Start - I2C_Write_Address - ADXL345_Reg_Address -
   *    Repeated_Start - I2C_Read_Address  - ADXL345_Read_Data - STOP
   */

  struct i2c_msg_s msg[2];
  uint8_t regval;
  int ret;

  /* Setup 8-bit ADXL345 address write message */

  msg[0].addr   = priv->config->address; /* 7-bit address */
  msg[0].flags  = 0;                     /* Write transaction, beginning with START */
  msg[0].buffer = &regaddr;              /* Transfer from this address */
  msg[0].length = 1;                     /* Send one byte following the address
                                          * (no STOP) */

  /* Set up the 8-bit ADXL345 data read message */

  msg[1].addr   = priv->config->address; /* 7-bit address */
  msg[1].flags  = I2C_M_READ;            /* Read transaction, beginning with Re-START */
  msg[1].buffer = &regval;               /* Transfer to this address */
  msg[1].length = 1;                     /* Receive one byte following the address
                                          * (then STOP) */

  /* Perform the transfer */

  ret = I2C_TRANSFER(priv->i2c, msg, 2);
  if (ret < 0)
    {
      sndbg("I2C_TRANSFER failed: %d\n", ret);
      return 0;
    }

#ifdef CONFIG_ADXL345_REGDEBUG
  dbg("%02x->%02x\n", regaddr, regval);
#endif
  return regval;
}
#endif

/****************************************************************************
 * Name: adxl345_putreg8
 *
 * Description:
 *   Write a value to an 8-bit ADXL345 register
 *
 ****************************************************************************/

#ifdef CONFIG_ADXL345_I2C
void adxl345_putreg8(FAR struct adxl345_dev_s *priv,
                      uint8_t regaddr, uint8_t regval)
{
  /* 8-bit data read sequence:
   *
   *  Start - I2C_Write_Address - ADXL345_Reg_Address - ADXL345_Write_Data - STOP
   */

  struct i2c_msg_s msg;
  uint8_t txbuffer[2];
  int ret;

#ifdef CONFIG_ADXL345_REGDEBUG
  dbg("%02x<-%02x\n", regaddr, regval);
#endif

  /* Setup to the data to be transferred.  Two bytes:  The ADXL345 register
   * address followed by one byte of data.
   */

  txbuffer[0] = regaddr;
  txbuffer[1] = regval;

  /* Setup 8-bit ADXL345 address write message */

  msg.addr   = priv->config->address; /* 7-bit address */
  msg.flags  = 0;                     /* Write transaction, beginning with START */
  msg.buffer = txbuffer;              /* Transfer from this address */
  msg.length = 2;                     /* Send two byte following the address
                                       * (then STOP) */

  /* Perform the transfer */

  ret = I2C_TRANSFER(priv->i2c, &msg, 1);
  if (ret < 0)
    {
      sndbg("I2C_TRANSFER failed: %d\n", ret);
    }
}
#endif

/****************************************************************************
 * Name: adxl345_getreg16
 *
 * Description:
 *   Read 16-bits of data from an STMPE-11 register
 *
 ****************************************************************************/

#ifdef CONFIG_ADXL345_I2C
uint16_t adxl345_getreg16(FAR struct adxl345_dev_s *priv, uint8_t regaddr)
{
  /* 16-bit data read sequence:
   *
   *  Start - I2C_Write_Address - ADXL345_Reg_Address -
   *    Repeated_Start - I2C_Read_Address  - ADXL345_Read_Data_1 -
   *      ADXL345_Read_Data_2 - STOP
   */

  struct i2c_msg_s msg[2];
  uint8_t rxbuffer[2];
  int ret;

  /* Setup 8-bit ADXL345 address write message */

  msg[0].addr   = priv->config->address; /* 7-bit address */
  msg[0].flags  = 0;                     /* Write transaction, beginning with START */
  msg[0].buffer = &regaddr;              /* Transfer from this address */
  msg[0].length = 1;                     /* Send one byte following the address
                                          * (no STOP) */

  /* Set up the 8-bit ADXL345 data read message */

  msg[1].addr   = priv->config->address; /* 7-bit address */
  msg[1].flags  = I2C_M_READ;            /* Read transaction, beginning with Re-START */
  msg[1].buffer = rxbuffer;              /* Transfer to this address */
  msg[1].length = 2;                     /* Receive two bytes following the address
                                          * (then STOP) */

  /* Perform the transfer */

  ret = I2C_TRANSFER(priv->i2c, msg, 2);
  if (ret < 0)
    {
      sndbg("I2C_TRANSFER failed: %d\n", ret);
      return 0;
    }

#ifdef CONFIG_ADXL345_REGDEBUG
  dbg("%02x->%02x%02x\n", regaddr, rxbuffer[0], rxbuffer[1]);
#endif
  return (uint16_t)rxbuffer[0] << 8 | (uint16_t)rxbuffer[1];
}
#endif

#endif /* CONFIG_SENSORS_ADXL345 */