upm/src/bmpx8x/bmpx8x.h
Jon Trulson c57a0d2c30 bmpx8x: rewrite in C; FTI; C++ wraps C
This driver has been rewritten from scratch.

See docs/apichanges.md for a list of API compatibility changes
compared to the original driver.

Signed-off-by: Jon Trulson <jtrulson@ics.com>
2017-04-05 11:29:08 -06:00

231 lines
6.8 KiB
C

/*
* Author: Jon Trulson <jtrulson@ics.com>
* Copyright (c) 2017 Intel Corporation.
*
* This driver was rewritten based on the original driver written by:
* Author: Yevgeniy Kiveisha <yevgeniy.kiveisha@intel.com>
*
* The MIT License
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#pragma once
#include <unistd.h>
#include <string.h>
#include <mraa/i2c.h>
#include "upm.h"
#include "bmpx8x_defs.h"
#ifdef __cplusplus
extern "C" {
#endif
/**
* @file bmpx8x.h
* @library bmpx8x
* @brief C API for the bmpx8x driver
*
* @include bmpx8x.c
*/
/**
* Device context
*/
typedef struct _bmpx8x_context {
mraa_i2c_context i2c;
// our oversampling (precision)
BMPX8X_OSS_T oversampling;
// compensated temperature and pressure
float temperature;
int pressure;
// compensation coefficients
int16_t ac1;
int16_t ac2;
int16_t ac3;
uint16_t ac4;
uint16_t ac5;
uint16_t ac6;
int16_t b1;
int16_t b2;
int16_t mb;
int16_t mc;
int16_t md;
} *bmpx8x_context;
/**
* BMPX8X initialization.
*
* By default, the device is initialized to it's highest accuracy
* (BMP085_OSS_ULTRAHIGHRES).
*
* @param bus I2C bus number.
* @param addr I2C address of the device.
* @return Device context, or NULL if an error occurred.
*/
bmpx8x_context bmpx8x_init(int bus, int addr);
/**
* BMPX8X close function.
*
* @param dev Device context.
*/
void bmpx8x_close(bmpx8x_context dev);
/**
* Return the chip ID.
*
* @param dev The device context.
* @return The chip ID.
*/
uint8_t bmpx8x_get_chip_id(const bmpx8x_context dev);
/**
* Initialize the device, read calibration data, and start
* operation. This function is called from bmpx8x_init() so it
* will not typically need to be called by a user unless the
* device is reset. This method will call
* bmpx8x_set_oversampling() with the passed parameter.
*
* @param dev The device context.
* @param oss One of the BMPX8X_OSS_T values. The default set
* at bmpx8x_init() time is BMP085_OSS_ULTRAHIGHRES.
* @return UPM result.
*/
upm_result_t bmpx8x_devinit(const bmpx8x_context dev,
BMPX8X_OSS_T oss);
/**
* Perform a device reset. The device will be reset as if it was
* just powered on. All compensation values will be lost. You
* should call bmpx8x_devinit() afterward, or perform the same
* steps that bmpx8x_devinit() performs before attempting to use
* the device.
*
* @param dev The device context.
* @return UPM result.
*/
upm_result_t bmpx8x_reset(const bmpx8x_context dev);
/**
* Update the internal stored values from sensor data.
*
* @param dev The device context.
* @return UPM result.
*/
upm_result_t bmpx8x_update(const bmpx8x_context dev);
/**
* Set the oversampling (precision mode) of the device. Higher
* precision requires more time to complete.
*
* @param dev The device context.
* @param oss The desired oversampling mode, one of the
* BMPX8X_OSS_T values.
*/
void bmpx8x_set_oversampling(const bmpx8x_context dev,
BMPX8X_OSS_T oss);
/**
* Returns the pressure in Pascals. bmpx8x_update() must have
* been called prior to calling this function.
*
* @param dev Device context.
* @return The pressure in Pascals.
*/
int bmpx8x_get_pressure(const bmpx8x_context dev);
/**
* Returns the temperature in degrees Celsius. bmpx8x_update()
* must have been called prior to calling this function.
*
* @param dev Device context.
* @return The temperature in degrees Celsius.
*/
float bmpx8x_get_temperature(const bmpx8x_context dev);
/**
* With a given current altitude, calculate pressure at sea level.
* bmpx8x_update() must have been called prior to calling this
* function.
*
* @param dev Device context.
* @param altitude Current altitude in Meters.
* @return The pressure in Pascals at sea level.
*/
int bmpx8x_get_sealevel_pressure(const bmpx8x_context dev,
float altitude);
/**
* With a given sea level, calculate altitude in meters.
* bmpx8x_update() must have been called prior to calling this
* function.
*
* @param dev Device context.
* @param sealevel Sea level pressure in Pascals. If a negative
* number, or zero is supplied, a default sealevel of 101325 Pa
* will be used instead.
* @return The current altitude in Meters.
*/
float bmpx8x_get_altitude(const bmpx8x_context dev, int sealevel);
/**
* Read a register.
*
* @param dev The device context.
* @param reg The register to read.
* @return The value of the register.
*/
uint8_t bmpx8x_read_reg(const bmpx8x_context dev, uint8_t reg);
/**
* Read contiguous registers into a buffer.
*
* @param dev The device context.
* @param buffer The buffer to store the results.
* @param len The number of registers to read.
* @return The number of bytes read, or -1 on error.
*/
int bmpx8x_read_regs(const bmpx8x_context dev, uint8_t reg,
uint8_t *buffer, int len);
/**
* Write to a register.
*
* @param dev The device context.
* @param reg The register to write to.
* @param val The value to write.
* @return UPM result.
*/
upm_result_t bmpx8x_write_reg(const bmpx8x_context dev,
uint8_t reg, uint8_t val);
#ifdef __cplusplus
}
#endif