/****************************************************************************
*
* Copyright (C) 2012 PX4 Development Team. All rights reserved.
*
* 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 PX4 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.
*
****************************************************************************/
/**
* @file bma180.cpp
* Driver for the Bosch BMA 180 MEMS accelerometer connected via SPI.
*/
#include <nuttx/config.h>
#include <sys/types.h>
#include <stdint.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdlib.h>
#include <semaphore.h>
#include <string.h>
#include <fcntl.h>
#include <poll.h>
#include <errno.h>
#include <stdio.h>
#include <math.h>
#include <unistd.h>
#include <systemlib/perf_counter.h>
#include <systemlib/err.h>
#include <nuttx/arch.h>
#include <nuttx/wqueue.h>
#include <nuttx/clock.h>
#include <drivers/drv_hrt.h>
#include <board_config.h>
#include <drivers/device/spi.h>
#include <drivers/drv_accel.h>
#include <drivers/device/ringbuffer.h>
/* oddly, ERROR is not defined for c++ */
#ifdef ERROR
# undef ERROR
#endif
static const int ERROR = -1;
#define DIR_READ (1<<7)
#define DIR_WRITE (0<<7)
#define ADDR_CHIP_ID 0x00
#define CHIP_ID 0x03
#define ADDR_ACC_X_LSB 0x02
#define ADDR_ACC_Y_LSB 0x04
#define ADDR_ACC_Z_LSB 0x06
#define ADDR_TEMPERATURE 0x08
#define ADDR_CTRL_REG0 0x0D
#define REG0_WRITE_ENABLE 0x10
#define ADDR_RESET 0x10
#define SOFT_RESET 0xB6
#define ADDR_BW_TCS 0x20
#define BW_TCS_BW_MASK (0xf<<4)
#define BW_TCS_BW_10HZ (0<<4)
#define BW_TCS_BW_20HZ (1<<4)
#define BW_TCS_BW_40HZ (2<<4)
#define BW_TCS_BW_75HZ (3<<4)
#define BW_TCS_BW_150HZ (4<<4)
#define BW_TCS_BW_300HZ (5<<4)
#define BW_TCS_BW_600HZ (6<<4)
#define BW_TCS_BW_1200HZ (7<<4)
#define ADDR_HIGH_DUR 0x27
#define HIGH_DUR_DIS_I2C (1<<0)
#define ADDR_TCO_Z 0x30
#define TCO_Z_MODE_MASK 0x3
#define ADDR_GAIN_Y 0x33
#define GAIN_Y_SHADOW_DIS (1<<0)
#define ADDR_OFFSET_LSB1 0x35
#define OFFSET_LSB1_RANGE_MASK (7<<1)
#define OFFSET_LSB1_RANGE_1G (0<<1)
#define OFFSET_LSB1_RANGE_2G (2<<1)
#define OFFSET_LSB1_RANGE_3G (3<<1)
#define OFFSET_LSB1_RANGE_4G (4<<1)
#define OFFSET_LSB1_RANGE_8G (5<<1)
#define OFFSET_LSB1_RANGE_16G (6<<1)
#define ADDR_OFFSET_T 0x37
#define OFFSET_T_READOUT_12BIT (1<<0)
extern "C" { __EXPORT int bma180_main(int argc, char *argv[]); }
class BMA180 : public device::SPI
{
public:
BMA180(int bus, spi_dev_e device);
virtual ~BMA180();
virtual int init();
virtual ssize_t read(struct file *filp, char *buffer, size_t buflen);
virtual int ioctl(struct file *filp, int cmd, unsigned long arg);
/**
* Diagnostics - print some basic information about the driver.
*/
void print_info();
protected:
virtual int probe();
private:
struct hrt_call _call;
unsigned _call_interval;
RingBuffer *_reports;
struct accel_scale _accel_scale;
float _accel_range_scale;
float _accel_range_m_s2;
orb_advert_t _accel_topic;
unsigned _current_lowpass;
unsigned _current_range;
perf_counter_t _sample_perf;
/**
* Start automatic measurement.
*/
void start();
/**
* Stop automatic measurement.
*/
void stop();
/**
* Static trampoline from the hrt_call context; because we don't have a
* generic hrt wrapper yet.
*
* Called by the HRT in interrupt context at the specified rate if
* automatic polling is enabled.
*
* @param arg Instance pointer for the driver that is polling.
*/
static void measure_trampoline(void *arg);
/**
* Fetch measurements from the sensor and update the report ring.
*/
void measure();
/**
* Read a register from the BMA180
*
* @param The register to read.
* @return The value that was read.
*/
uint8_t read_reg(unsigned reg);
/**
* Write a register in the BMA180
*
* @param reg The register to write.
* @param value The new value to write.
*/
void write_reg(unsigned reg, uint8_t value);
/**
* Modify a register in the BMA180
*
* Bits are cleared before bits are set.
*
* @param reg The register to modify.
* @param clearbits Bits in the register to clear.
* @param setbits Bits in the register to set.
*/
void modify_reg(unsigned reg, uint8_t clearbits, uint8_t setbits);
/**
* Set the BMA180 measurement range.
*
* @param max_g The maximum G value the range must support.
* @return OK if the value can be supported, -ERANGE otherwise.
*/
int set_range(unsigned max_g);
/**
* Set the BMA180 internal lowpass filter frequency.
*
* @param frequency The internal lowpass filter frequency is set to a value
* equal or greater to this.
* Zero selects the highest frequency supported.
* @return OK if the value can be supported.
*/
int set_lowpass(unsigned frequency);
};
BMA180::BMA180(int bus, spi_dev_e device) :
SPI("BMA180", ACCEL_DEVICE_PATH, bus, device, SPIDEV_MODE3, 8000000),
_call_interval(0),
_reports(nullptr),
_accel_range_scale(0.0f),
_accel_range_m_s2(0.0f),
_accel_topic(-1),
_current_lowpass(0),
_current_range(0),
_sample_perf(perf_alloc(PC_ELAPSED, "bma180_read"))
{
// enable debug() calls
_debug_enabled = true;
// default scale factors
_accel_scale.x_offset = 0;
_accel_scale.x_scale = 1.0f;
_accel_scale.y_offset = 0;
_accel_scale.y_scale = 1.0f;
_accel_scale.z_offset = 0;
_accel_scale.z_scale = 1.0f;
}
BMA180::~BMA180()
{
/* make sure we are truly inactive */
stop();
/* free any existing reports */
if (_reports != nullptr)
delete _reports;
/* delete the perf counter */
perf_free(_sample_perf);
}
int
BMA180::init()
{
int ret = ERROR;
/* do SPI init (and probe) first */
if (SPI::init() != OK)
goto out;
/* allocate basic report buffers */
_reports = new RingBuffer(2, sizeof(accel_report));
if (_reports == nullptr)
goto out;
/* advertise sensor topic */
struct accel_report zero_report;
memset(&zero_report, 0, sizeof(zero_report));
_accel_topic = orb_advertise(ORB_ID(sensor_accel), &zero_report);
/* perform soft reset (p48) */
write_reg(ADDR_RESET, SOFT_RESET);
/* wait 10 ms (datasheet incorrectly lists 10 us on page 49) */
usleep(10000);
/* enable writing to chip config */
modify_reg(ADDR_CTRL_REG0, 0, REG0_WRITE_ENABLE);
/* disable I2C interface */
modify_reg(ADDR_HIGH_DUR, HIGH_DUR_DIS_I2C, 0);
/* switch to low-noise mode */
modify_reg(ADDR_TCO_Z, TCO_Z_MODE_MASK, 0);
/* disable 12-bit mode */
modify_reg(ADDR_OFFSET_T, OFFSET_T_READOUT_12BIT, 0);
/* disable shadow-disable mode */
modify_reg(ADDR_GAIN_Y, GAIN_Y_SHADOW_DIS, 0);
/* disable writing to chip config */
modify_reg(ADDR_CTRL_REG0, REG0_WRITE_ENABLE, 0);
if (set_range(4)) warnx("Failed setting range");
if (set_lowpass(75)) warnx("Failed setting lowpass");
if (read_reg(ADDR_CHIP_ID) == CHIP_ID) {
ret = OK;
} else {
ret = ERROR;
}
out:
return ret;
}
int
BMA180::probe()
{
/* dummy read to ensure SPI state machine is sane */
read_reg(ADDR_CHIP_ID);
if (read_reg(ADDR_CHIP_ID) == CHIP_ID)
return OK;
return -EIO;
}
ssize_t
BMA180::read(struct file *filp, char *buffer, size_t buflen)
{
unsigned count = buflen / sizeof(struct accel_report);
struct accel_report *arp = reinterpret_cast<struct accel_report *>(buffer);
int ret = 0;
/* buffer must be large enough */
if (count < 1)
return -ENOSPC;
/* if automatic measurement is enabled */
if (_call_interval > 0) {
/*
* While there is space in the caller's buffer, and reports, copy them.
* Note that we may be pre-empted by the measurement code while we are doing this;
* we are careful to avoid racing with it.
*/
while (count--) {
if (_reports->get(arp)) {
ret += sizeof(*arp);
arp++;
}
}
/* if there was no data, warn the caller */
return ret ? ret : -EAGAIN;
}
/* manual measurement */
_reports->flush();
measure();
/* measurement will have generated a report, copy it out */
if (_reports->get(arp))
ret = sizeof(*arp);
return ret;
}
int
BMA180::ioctl(struct file *filp, int cmd, unsigned long arg)
{
switch (cmd) {
case SENSORIOCSPOLLRATE: {
switch (arg) {
/* switching to manual polling */
case SENSOR_POLLRATE_MANUAL:
stop();
_call_interval = 0;
return OK;
/* external signalling not supported */
case SENSOR_POLLRATE_EXTERNAL:
/* zero would be bad */
case 0:
return -EINVAL;
/* set default/max polling rate */
case SENSOR_POLLRATE_MAX:
case SENSOR_POLLRATE_DEFAULT:
/* With internal low pass filters enabled, 250 Hz is sufficient */
return ioctl(filp, SENSORIOCSPOLLRATE, 250);
/* adjust to a legal polling interval in Hz */
default: {
/* do we need to start internal polling? */
bool want_start = (_call_interval == 0);
/* convert hz to hrt interval via microseconds */
unsigned ticks = 1000000 / arg;
/* check against maximum sane rate */
if (ticks < 1000)
return -EINVAL;
/* update interval for next measurement */
/* XXX this is a bit shady, but no other way to adjust... */
_call.period = _call_interval = ticks;
/* if we need to start the poll state machine, do it */
if (want_start)
start();
return OK;
}
}
}
case SENSORIOCGPOLLRATE:
if (_call_interval == 0)
return SENSOR_POLLRATE_MANUAL;
return 1000000 / _call_interval;
case SENSORIOCSQUEUEDEPTH: {
/* lower bound is mandatory, upper bound is a sanity check */
if ((arg < 2) || (arg > 100))
return -EINVAL;
irqstate_t flags = irqsave();
if (!_reports->resize(arg)) {
irqrestore(flags);
return -ENOMEM;
}
irqrestore(flags);
return OK;
}
case SENSORIOCGQUEUEDEPTH:
return _reports->size();
case SENSORIOCRESET:
/* XXX implement */
return -EINVAL;
case ACCELIOCSSAMPLERATE: /* sensor sample rate is not (really) adjustable */
return -EINVAL;
case ACCELIOCGSAMPLERATE:
return 1200; /* always operating in low-noise mode */
case ACCELIOCSLOWPASS:
return set_lowpass(arg);
case ACCELIOCGLOWPASS:
return _current_lowpass;
case ACCELIOCSSCALE:
/* copy scale in */
memcpy(&_accel_scale, (struct accel_scale *) arg, sizeof(_accel_scale));
return OK;
case ACCELIOCGSCALE:
/* copy scale out */
memcpy((struct accel_scale *) arg, &_accel_scale, sizeof(_accel_scale));
return OK;
case ACCELIOCSRANGE:
return set_range(arg);
case ACCELIOCGRANGE:
return _current_range;
default:
/* give it to the superclass */
return SPI::ioctl(filp, cmd, arg);
}
}
uint8_t
BMA180::read_reg(unsigned reg)
{
uint8_t cmd[2];
cmd[0] = reg | DIR_READ;
transfer(cmd, cmd, sizeof(cmd));
return cmd[1];
}
void
BMA180::write_reg(unsigned reg, uint8_t value)
{
uint8_t cmd[2];
cmd[0] = reg | DIR_WRITE;
cmd[1] = value;
transfer(cmd, nullptr, sizeof(cmd));
}
void
BMA180::modify_reg(unsigned reg, uint8_t clearbits, uint8_t setbits)
{
uint8_t val;
val = read_reg(reg);
val &= ~clearbits;
val |= setbits;
write_reg(reg, val);
}
int
BMA180::set_range(unsigned max_g)
{
uint8_t rangebits;
if (max_g == 0)
max_g = 16;
if (max_g > 16)
return -ERANGE;
if (max_g <= 2) {
_current_range = 2;
rangebits = OFFSET_LSB1_RANGE_2G;
} else if (max_g <= 3) {
_current_range = 3;
rangebits = OFFSET_LSB1_RANGE_3G;
} else if (max_g <= 4) {
_current_range = 4;
rangebits = OFFSET_LSB1_RANGE_4G;
} else if (max_g <= 8) {
_current_range = 8;
rangebits = OFFSET_LSB1_RANGE_8G;
} else if (max_g <= 16) {
_current_range = 16;
rangebits = OFFSET_LSB1_RANGE_16G;
} else {
return -EINVAL;
}
/* set new range scaling factor */
_accel_range_m_s2 = _current_range * 9.80665f;
_accel_range_scale = _accel_range_m_s2 / 8192.0f;
/* enable writing to chip config */
modify_reg(ADDR_CTRL_REG0, 0, REG0_WRITE_ENABLE);
/* adjust sensor configuration */
modify_reg(ADDR_OFFSET_LSB1, OFFSET_LSB1_RANGE_MASK, rangebits);
/* block writing to chip config */
modify_reg(ADDR_CTRL_REG0, REG0_WRITE_ENABLE, 0);
/* check if wanted value is now in register */
return !((read_reg(ADDR_OFFSET_LSB1) & OFFSET_LSB1_RANGE_MASK) ==
(OFFSET_LSB1_RANGE_MASK & rangebits));
}
int
BMA180::set_lowpass(unsigned frequency)
{
uint8_t bwbits;
if (frequency > 1200) {
return -ERANGE;
} else if (frequency > 600) {
bwbits = BW_TCS_BW_1200HZ;
} else if (frequency > 300) {
bwbits = BW_TCS_BW_600HZ;
} else if (frequency > 150) {
bwbits = BW_TCS_BW_300HZ;
} else if (frequency > 75) {
bwbits = BW_TCS_BW_150HZ;
} else if (frequency > 40) {
bwbits = BW_TCS_BW_75HZ;
} else if (frequency > 20) {
bwbits = BW_TCS_BW_40HZ;
} else if (frequency > 10) {
bwbits = BW_TCS_BW_20HZ;
} else {
bwbits = BW_TCS_BW_10HZ;
}
/* enable writing to chip config */
modify_reg(ADDR_CTRL_REG0, 0, REG0_WRITE_ENABLE);
/* adjust sensor configuration */
modify_reg(ADDR_BW_TCS, BW_TCS_BW_MASK, bwbits);
/* block writing to chip config */
modify_reg(ADDR_CTRL_REG0, REG0_WRITE_ENABLE, 0);
/* check if wanted value is now in register */
return !((read_reg(ADDR_BW_TCS) & BW_TCS_BW_MASK) ==
(BW_TCS_BW_MASK & bwbits));
}
void
BMA180::start()
{
/* make sure we are stopped first */
stop();
/* reset the report ring */
_reports->flush();
/* start polling at the specified rate */
hrt_call_every(&_call, 1000, _call_interval, (hrt_callout)&BMA180::measure_trampoline, this);
}
void
BMA180::stop()
{
hrt_cancel(&_call);
}
void
BMA180::measure_trampoline(void *arg)
{
BMA180 *dev = (BMA180 *)arg;
/* make another measurement */
dev->measure();
}
void
BMA180::measure()
{
/* BMA180 measurement registers */
// #pragma pack(push, 1)
// struct {
// uint8_t cmd;
// int16_t x;
// int16_t y;
// int16_t z;
// } raw_report;
// #pragma pack(pop)
struct accel_report report;
/* start the performance counter */
perf_begin(_sample_perf);
/*
* Fetch the full set of measurements from the BMA180 in one pass;
* starting from the X LSB.
*/
//raw_report.cmd = ADDR_ACC_X_LSB;
// XXX PX4DEV transfer((uint8_t *)&raw_report, (uint8_t *)&raw_report, sizeof(raw_report));
/*
* Adjust and scale results to SI units.
*
* Note that we ignore the "new data" bits. At any time we read, each
* of the axis measurements are the "most recent", even if we've seen
* them before. There is no good way to synchronise with the internal
* measurement flow without using the external interrupt.
*/
report.timestamp = hrt_absolute_time();
/*
* y of board is x of sensor and x of board is -y of sensor
* perform only the axis assignment here.
* Two non-value bits are discarded directly
*/
report.y_raw = read_reg(ADDR_ACC_X_LSB + 0);
report.y_raw |= read_reg(ADDR_ACC_X_LSB + 1) << 8;
report.x_raw = read_reg(ADDR_ACC_X_LSB + 2);
report.x_raw |= read_reg(ADDR_ACC_X_LSB + 3) << 8;
report.z_raw = read_reg(ADDR_ACC_X_LSB + 4);
report.z_raw |= read_reg(ADDR_ACC_X_LSB + 5) << 8;
/* discard two non-value bits in the 16 bit measurement */
report.x_raw = (report.x_raw / 4);
report.y_raw = (report.y_raw / 4);
report.z_raw = (report.z_raw / 4);
/* invert y axis, due to 14 bit data no overflow can occur in the negation */
report.y_raw = -report.y_raw;
report.x = ((report.x_raw * _accel_range_scale) - _accel_scale.x_offset) * _accel_scale.x_scale;
report.y = ((report.y_raw * _accel_range_scale) - _accel_scale.y_offset) * _accel_scale.y_scale;
report.z = ((report.z_raw * _accel_range_scale) - _accel_scale.z_offset) * _accel_scale.z_scale;
report.scaling = _accel_range_scale;
report.range_m_s2 = _accel_range_m_s2;
_reports->force(&report);
/* notify anyone waiting for data */
poll_notify(POLLIN);
/* publish for subscribers */
orb_publish(ORB_ID(sensor_accel), _accel_topic, &report);
/* stop the perf counter */
perf_end(_sample_perf);
}
void
BMA180::print_info()
{
perf_print_counter(_sample_perf);
_reports->print_info("report queue");
}
/**
* Local functions in support of the shell command.
*/
namespace bma180
{
BMA180 *g_dev;
void start();
void test();
void reset();
void info();
/**
* Start the driver.
*/
void
start()
{
int fd;
if (g_dev != nullptr)
errx(1, "already started");
/* create the driver */
g_dev = new BMA180(1 /* XXX magic number */, (spi_dev_e)PX4_SPIDEV_ACCEL);
if (g_dev == nullptr)
goto fail;
if (OK != g_dev->init())
goto fail;
/* set the poll rate to default, starts automatic data collection */
fd = open(ACCEL_DEVICE_PATH, O_RDONLY);
if (fd < 0)
goto fail;
if (ioctl(fd, SENSORIOCSPOLLRATE, SENSOR_POLLRATE_DEFAULT) < 0)
goto fail;
exit(0);
fail:
if (g_dev != nullptr) {
delete g_dev;
g_dev = nullptr;
}
errx(1, "driver start failed");
}
/**
* Perform some basic functional tests on the driver;
* make sure we can collect data from the sensor in polled
* and automatic modes.
*/
void
test()
{
int fd = -1;
struct accel_report a_report;
ssize_t sz;
/* get the driver */
fd = open(ACCEL_DEVICE_PATH, O_RDONLY);
if (fd < 0)
err(1, "%s open failed (try 'bma180 start' if the driver is not running)",
ACCEL_DEVICE_PATH);
/* reset to manual polling */
if (ioctl(fd, SENSORIOCSPOLLRATE, SENSOR_POLLRATE_MANUAL) < 0)
err(1, "reset to manual polling");
/* do a simple demand read */
sz = read(fd, &a_report, sizeof(a_report));
if (sz != sizeof(a_report))
err(1, "immediate acc read failed");
warnx("single read");
warnx("time: %lld", a_report.timestamp);
warnx("acc x: \t%8.4f\tm/s^2", (double)a_report.x);
warnx("acc y: \t%8.4f\tm/s^2", (double)a_report.y);
warnx("acc z: \t%8.4f\tm/s^2", (double)a_report.z);
warnx("acc x: \t%d\traw 0x%0x", (short)a_report.x_raw, (unsigned short)a_report.x_raw);
warnx("acc y: \t%d\traw 0x%0x", (short)a_report.y_raw, (unsigned short)a_report.y_raw);
warnx("acc z: \t%d\traw 0x%0x", (short)a_report.z_raw, (unsigned short)a_report.z_raw);
warnx("acc range: %8.4f m/s^2 (%8.4f g)", (double)a_report.range_m_s2,
(double)(a_report.range_m_s2 / 9.81f));
/* XXX add poll-rate tests here too */
reset();
errx(0, "PASS");
}
/**
* Reset the driver.
*/
void
reset()
{
int fd = open(ACCEL_DEVICE_PATH, O_RDONLY);
if (fd < 0)
err(1, "failed ");
if (ioctl(fd, SENSORIOCRESET, 0) < 0)
err(1, "driver reset failed");
if (ioctl(fd, SENSORIOCSPOLLRATE, SENSOR_POLLRATE_DEFAULT) < 0)
err(1, "driver poll restart failed");
exit(0);
}
/**
* Print a little info about the driver.
*/
void
info()
{
if (g_dev == nullptr)
errx(1, "BMA180: driver not running");
printf("state @ %p\n", g_dev);
g_dev->print_info();
exit(0);
}
} // namespace
int
bma180_main(int argc, char *argv[])
{
/*
* Start/load the driver.
*/
if (!strcmp(argv[1], "start"))
bma180::start();
/*
* Test the driver/device.
*/
if (!strcmp(argv[1], "test"))
bma180::test();
/*
* Reset the driver.
*/
if (!strcmp(argv[1], "reset"))
bma180::reset();
/*
* Print driver information.
*/
if (!strcmp(argv[1], "info"))
bma180::info();
errx(1, "unrecognised command, try 'start', 'test', 'reset' or 'info'");
}