nuttx/drivers/sensors/adxl345.h

/****************************************************************************
 * drivers/sensors/adxl345.h
 *
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.  The
 * ASF licenses this file to you 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.
 *
 ****************************************************************************/

#ifndef __DRIVERS_SENSORS_ADXL345_H
#define __DRIVERS_SENSORS_ADXL345_H

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

#include <nuttx/config.h>

#include <nuttx/wdog.h>
#include <nuttx/clock.h>
#include <nuttx/wqueue.h>
#include <nuttx/mutex.h>
#include <nuttx/semaphore.h>
#include <nuttx/sensors/adxl345.h>

#if defined(CONFIG_SENSORS_ADXL345)

/****************************************************************************
 * Pre-processor Definitions
 ****************************************************************************/

#ifdef CONFIG_ADXL345_I2C
#  error "Only the ADXL345 SPI interface is supported by this driver"
#endif

/* Driver support ***********************************************************/

/* This format is used to construct the /dev/accel[n] device driver path.
 *  It defined here so that it will be used consistently in all places.
 */

#define DEV_FORMAT   "/dev/accel%d"
#define DEV_NAMELEN  16

/* Driver flags */

#define ADXL345_STAT_INITIALIZED  1 /* Device has been initialized */

/****************************************************************************
 * Public Types
 ****************************************************************************/

/* This defines type of events */

enum adxl345_event
{
  DATA_READY = 0,                      /* New data available */
  SINGLE_TAP,                          /* A tap event detected */
  DOUBLE_TAP,                          /* A double tap event detected */
  ACTIVITY,                            /* Activity detected */
  INACTIVITY,                          /* Inactivity detected */
  FREE_FAL,                            /* Free fall event */
  WATERMARK,                           /* Number samples in FIFO is equal to sample bits */
  OVERRUN,                             /* New data replaced unread data */
};

/* This defines operating mode */

enum adxl345_mode
{
  BYPASS_MODE = 0,                     /* Bypass FIFO, then it remain empty */
  FIFO_MODE,                           /* Sampled data are put in FIFO, up to 32 samples */
  STREAM_MODE,                         /* Sampled data are put in FIFO, when full remove old samples */
  TRIGGER_MODE                         /* Similar to Stream Mode, but when Trigger event happen FIFO freeze */
};

/* This structure describes the results of one ADXL345 sample */

struct adxl345_sample_s
{
  uint16_t data_x;                     /* Measured X-axis acceleration */
  uint16_t data_y;                     /* Measured Y-axis acceleration */
  uint8_t  data_z;                     /* Measured Z-axis acceleration */
};

/* This structure represents the state of the ADXL345 driver */

struct adxl345_dev_s
{
  /* Common fields */

  FAR struct adxl345_config_s *config; /* Board configuration data */
  mutex_t lock;                        /* Manages exclusive access to this structure */
#ifdef CONFIG_ADXL345_SPI
  FAR struct spi_dev_s *spi;           /* Saved SPI driver instance */
#else
  FAR struct i2c_master_s *i2c;        /* Saved I2C driver instance */
#endif

  uint8_t status;                      /* See ADXL345_STAT_* definitions */
  struct work_s work;                  /* Supports the interrupt handling "bottom half" */

#ifdef CONFIG_ADXL345_REFCNT
  uint8_t crefs;                       /* Number of times the device has been opened */
#endif
  uint8_t nwaiters;                    /* Number of threads waiting for ADXL345 data */

  uint16_t ofsx;                       /* Offset X value */
  uint16_t ofsy;                       /* Offset Y value */
  uint16_t ofsz;                       /* Offset Z value */
  sem_t waitsem;                       /* Used to wait for the availability of data */

  struct work_s timeout;               /* Supports timeout work */
  struct adxl345_sample_s sample;      /* Last sampled accelerometer data */
};

/****************************************************************************
 * Public Function Prototypes
 ****************************************************************************/

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

uint8_t adxl345_getreg8(FAR struct adxl345_dev_s *priv, uint8_t regaddr);

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

void adxl345_putreg8(FAR struct adxl345_dev_s *priv,
                     uint8_t regaddr, uint8_t regval);

/****************************************************************************
 * Name: adxl345_getreg16
 *
 * Description:
 *   Read 16-bits of data from an ADXL345 register
 *
 ****************************************************************************/

uint16_t adxl345_getreg16(FAR struct adxl345_dev_s *priv, uint8_t regaddr);

/****************************************************************************
 * Name: adxl345_accworker
 *
 * Description:
 *   Handle accelerometer interrupt events
 *   (this function actually executes in the context of the worker thread).
 *
 ****************************************************************************/

void adxl345_accworker(FAR struct adxl345_dev_s *priv,
                       uint8_t intsta) weak_function;

#endif /* CONFIG_SENSORS_ADXL345 */
#endif /* __DRIVERS_SENSORS_ADXL345_H */