/****************************************************************************
*
* Copyright (c) 2012, 2013 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 l3gd20.cpp
* Driver for the ST L3GD20 MEMS gyro 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/clock.h>
#include <drivers/drv_hrt.h>
#include <arch/board/board.h>
#include <drivers/device/spi.h>
#include <drivers/drv_gyro.h>
/* oddly, ERROR is not defined for c++ */
#ifdef ERROR
# undef ERROR
#endif
static const int ERROR = -1;
/* SPI protocol address bits */
#define DIR_READ (1<<7)
#define DIR_WRITE (0<<7)
#define ADDR_INCREMENT (1<<6)
/* register addresses */
#define ADDR_WHO_AM_I 0x0F
#define WHO_I_AM_H 0xD7
#define WHO_I_AM 0xD4
#define ADDR_CTRL_REG1 0x20
#define REG1_RATE_LP_MASK 0xF0 /* Mask to guard partial register update */
/* keep lowpass low to avoid noise issues */
#define RATE_95HZ_LP_25HZ ((0<<7) | (0<<6) | (0<<5) | (1<<4))
#define RATE_190HZ_LP_25HZ ((0<<7) | (1<<6) | (1<<5) | (1<<4))
#define RATE_380HZ_LP_30HZ ((1<<7) | (0<<6) | (1<<5) | (1<<4))
#define RATE_760HZ_LP_30HZ ((1<<7) | (1<<6) | (1<<5) | (1<<4))
#define ADDR_CTRL_REG2 0x21
#define ADDR_CTRL_REG3 0x22
#define ADDR_CTRL_REG4 0x23
#define REG4_RANGE_MASK 0x30 /* Mask to guard partial register update */
#define RANGE_250DPS (0<<4)
#define RANGE_500DPS (1<<4)
#define RANGE_2000DPS (3<<4)
#define ADDR_CTRL_REG5 0x24
#define ADDR_REFERENCE 0x25
#define ADDR_OUT_TEMP 0x26
#define ADDR_STATUS_REG 0x27
#define ADDR_OUT_X_L 0x28
#define ADDR_OUT_X_H 0x29
#define ADDR_OUT_Y_L 0x2A
#define ADDR_OUT_Y_H 0x2B
#define ADDR_OUT_Z_L 0x2C
#define ADDR_OUT_Z_H 0x2D
#define ADDR_FIFO_CTRL_REG 0x2E
#define ADDR_FIFO_SRC_REG 0x2F
#define ADDR_INT1_CFG 0x30
#define ADDR_INT1_SRC 0x31
#define ADDR_INT1_TSH_XH 0x32
#define ADDR_INT1_TSH_XL 0x33
#define ADDR_INT1_TSH_YH 0x34
#define ADDR_INT1_TSH_YL 0x35
#define ADDR_INT1_TSH_ZH 0x36
#define ADDR_INT1_TSH_ZL 0x37
#define ADDR_INT1_DURATION 0x38
/* Internal configuration values */
#define REG1_POWER_NORMAL (1<<3)
#define REG1_Z_ENABLE (1<<2)
#define REG1_Y_ENABLE (1<<1)
#define REG1_X_ENABLE (1<<0)
#define REG4_BDU (1<<7)
#define REG4_BLE (1<<6)
//#define REG4_SPI_3WIRE (1<<0)
#define REG5_FIFO_ENABLE (1<<6)
#define REG5_REBOOT_MEMORY (1<<7)
#define STATUS_ZYXOR (1<<7)
#define STATUS_ZOR (1<<6)
#define STATUS_YOR (1<<5)
#define STATUS_XOR (1<<4)
#define STATUS_ZYXDA (1<<3)
#define STATUS_ZDA (1<<2)
#define STATUS_YDA (1<<1)
#define STATUS_XDA (1<<0)
#define FIFO_CTRL_BYPASS_MODE (0<<5)
#define FIFO_CTRL_FIFO_MODE (1<<5)
#define FIFO_CTRL_STREAM_MODE (1<<6)
#define FIFO_CTRL_STREAM_TO_FIFO_MODE (3<<5)
#define FIFO_CTRL_BYPASS_TO_STREAM_MODE (1<<7)
extern "C" { __EXPORT int l3gd20_main(int argc, char *argv[]); }
class L3GD20 : public device::SPI
{
public:
L3GD20(int bus, const char* path, spi_dev_e device);
virtual ~L3GD20();
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;
unsigned _num_reports;
volatile unsigned _next_report;
volatile unsigned _oldest_report;
struct gyro_report *_reports;
struct gyro_scale _gyro_scale;
float _gyro_range_scale;
float _gyro_range_rad_s;
orb_advert_t _gyro_topic;
unsigned _current_rate;
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 L3GD20
*
* @param The register to read.
* @return The value that was read.
*/
uint8_t read_reg(unsigned reg);
/**
* Write a register in the L3GD20
*
* @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 L3GD20
*
* 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 L3GD20 measurement range.
*
* @param max_dps The measurement range is set to permit reading at least
* this rate in degrees per second.
* Zero selects the maximum supported range.
* @return OK if the value can be supported, -ERANGE otherwise.
*/
int set_range(unsigned max_dps);
/**
* Set the L3GD20 internal sampling frequency.
*
* @param frequency The internal sampling frequency is set to not less than
* this value.
* Zero selects the maximum rate supported.
* @return OK if the value can be supported.
*/
int set_samplerate(unsigned frequency);
};
/* helper macro for handling report buffer indices */
#define INCREMENT(_x, _lim) do { _x++; if (_x >= _lim) _x = 0; } while(0)
L3GD20::L3GD20(int bus, const char* path, spi_dev_e device) :
SPI("L3GD20", path, bus, device, SPIDEV_MODE3, 8000000),
_call_interval(0),
_num_reports(0),
_next_report(0),
_oldest_report(0),
_reports(nullptr),
_gyro_range_scale(0.0f),
_gyro_range_rad_s(0.0f),
_gyro_topic(-1),
_current_rate(0),
_current_range(0),
_sample_perf(perf_alloc(PC_ELAPSED, "l3gd20_read"))
{
// enable debug() calls
_debug_enabled = true;
// default scale factors
_gyro_scale.x_offset = 0;
_gyro_scale.x_scale = 1.0f;
_gyro_scale.y_offset = 0;
_gyro_scale.y_scale = 1.0f;
_gyro_scale.z_offset = 0;
_gyro_scale.z_scale = 1.0f;
}
L3GD20::~L3GD20()
{
/* 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
L3GD20::init()
{
int ret = ERROR;
/* do SPI init (and probe) first */
if (SPI::init() != OK)
goto out;
/* allocate basic report buffers */
_num_reports = 2;
_oldest_report = _next_report = 0;
_reports = new struct gyro_report[_num_reports];
if (_reports == nullptr)
goto out;
/* advertise sensor topic */
memset(&_reports[0], 0, sizeof(_reports[0]));
_gyro_topic = orb_advertise(ORB_ID(sensor_gyro), &_reports[0]);
/* set default configuration */
write_reg(ADDR_CTRL_REG1, REG1_POWER_NORMAL | REG1_Z_ENABLE | REG1_Y_ENABLE | REG1_X_ENABLE);
write_reg(ADDR_CTRL_REG2, 0); /* disable high-pass filters */
write_reg(ADDR_CTRL_REG3, 0); /* no interrupts - we don't use them */
write_reg(ADDR_CTRL_REG4, REG4_BDU);
write_reg(ADDR_CTRL_REG5, 0);
write_reg(ADDR_CTRL_REG5, REG5_FIFO_ENABLE); /* disable wake-on-interrupt */
write_reg(ADDR_FIFO_CTRL_REG, FIFO_CTRL_STREAM_MODE); /* Enable FIFO, old data is overwritten */
set_range(2000); /* default to 2000dps */
set_samplerate(0); /* max sample rate */
ret = OK;
out:
return ret;
}
int
L3GD20::probe()
{
/* read dummy value to void to clear SPI statemachine on sensor */
(void)read_reg(ADDR_WHO_AM_I);
/* verify that the device is attached and functioning, accept L3GD20 and L3GD20H */
if (read_reg(ADDR_WHO_AM_I) == WHO_I_AM || read_reg(ADDR_WHO_AM_I) == WHO_I_AM_H)
return OK;
return -EIO;
}
ssize_t
L3GD20::read(struct file *filp, char *buffer, size_t buflen)
{
unsigned count = buflen / sizeof(struct gyro_report);
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 (_oldest_report != _next_report) {
memcpy(buffer, _reports + _oldest_report, sizeof(*_reports));
ret += sizeof(_reports[0]);
INCREMENT(_oldest_report, _num_reports);
}
}
/* if there was no data, warn the caller */
return ret ? ret : -EAGAIN;
}
/* manual measurement */
_oldest_report = _next_report = 0;
measure();
/* measurement will have generated a report, copy it out */
memcpy(buffer, _reports, sizeof(*_reports));
ret = sizeof(*_reports);
return ret;
}
int
L3GD20::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: {
/* account for sentinel in the ring */
arg++;
/* lower bound is mandatory, upper bound is a sanity check */
if ((arg < 2) || (arg > 100))
return -EINVAL;
/* allocate new buffer */
struct gyro_report *buf = new struct gyro_report[arg];
if (nullptr == buf)
return -ENOMEM;
/* reset the measurement state machine with the new buffer, free the old */
stop();
delete[] _reports;
_num_reports = arg;
_reports = buf;
start();
return OK;
}
case SENSORIOCGQUEUEDEPTH:
return _num_reports - 1;
case SENSORIOCRESET:
/* XXX implement */
return -EINVAL;
case GYROIOCSSAMPLERATE:
return set_samplerate(arg);
case GYROIOCGSAMPLERATE:
return _current_rate;
case GYROIOCSLOWPASS:
case GYROIOCGLOWPASS:
/* XXX not implemented due to wacky interaction with samplerate */
return -EINVAL;
case GYROIOCSSCALE:
/* copy scale in */
memcpy(&_gyro_scale, (struct gyro_scale *) arg, sizeof(_gyro_scale));
return OK;
case GYROIOCGSCALE:
/* copy scale out */
memcpy((struct gyro_scale *) arg, &_gyro_scale, sizeof(_gyro_scale));
return OK;
case GYROIOCSRANGE:
return set_range(arg);
case GYROIOCGRANGE:
return _current_range;
default:
/* give it to the superclass */
return SPI::ioctl(filp, cmd, arg);
}
}
uint8_t
L3GD20::read_reg(unsigned reg)
{
uint8_t cmd[2];
cmd[0] = reg | DIR_READ;
transfer(cmd, cmd, sizeof(cmd));
return cmd[1];
}
void
L3GD20::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
L3GD20::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
L3GD20::set_range(unsigned max_dps)
{
uint8_t bits = REG4_BDU;
if (max_dps == 0)
max_dps = 2000;
if (max_dps <= 250) {
_current_range = 250;
bits |= RANGE_250DPS;
} else if (max_dps <= 500) {
_current_range = 500;
bits |= RANGE_500DPS;
} else if (max_dps <= 2000) {
_current_range = 2000;
bits |= RANGE_2000DPS;
} else {
return -EINVAL;
}
_gyro_range_rad_s = _current_range / 180.0f * M_PI_F;
_gyro_range_scale = _gyro_range_rad_s / 32768.0f;
write_reg(ADDR_CTRL_REG4, bits);
return OK;
}
int
L3GD20::set_samplerate(unsigned frequency)
{
uint8_t bits = REG1_POWER_NORMAL | REG1_Z_ENABLE | REG1_Y_ENABLE | REG1_X_ENABLE;
if (frequency == 0)
frequency = 760;
if (frequency <= 95) {
_current_rate = 95;
bits |= RATE_95HZ_LP_25HZ;
} else if (frequency <= 190) {
_current_rate = 190;
bits |= RATE_190HZ_LP_25HZ;
} else if (frequency <= 380) {
_current_rate = 380;
bits |= RATE_380HZ_LP_30HZ;
} else if (frequency <= 760) {
_current_rate = 760;
bits |= RATE_760HZ_LP_30HZ;
} else {
return -EINVAL;
}
write_reg(ADDR_CTRL_REG1, bits);
return OK;
}
void
L3GD20::start()
{
/* make sure we are stopped first */
stop();
/* reset the report ring */
_oldest_report = _next_report = 0;
/* start polling at the specified rate */
hrt_call_every(&_call, 1000, _call_interval, (hrt_callout)&L3GD20::measure_trampoline, this);
}
void
L3GD20::stop()
{
hrt_cancel(&_call);
}
void
L3GD20::measure_trampoline(void *arg)
{
L3GD20 *dev = (L3GD20 *)arg;
/* make another measurement */
dev->measure();
}
void
L3GD20::measure()
{
/* status register and data as read back from the device */
#pragma pack(push, 1)
struct {
uint8_t cmd;
uint8_t temp;
uint8_t status;
int16_t x;
int16_t y;
int16_t z;
} raw_report;
#pragma pack(pop)
gyro_report *report = &_reports[_next_report];
/* start the performance counter */
perf_begin(_sample_perf);
/* fetch data from the sensor */
raw_report.cmd = ADDR_OUT_TEMP | DIR_READ | ADDR_INCREMENT;
transfer((uint8_t *)&raw_report, (uint8_t *)&raw_report, sizeof(raw_report));
/*
* 1) Scale raw value to SI units using scaling from datasheet.
* 2) Subtract static offset (in SI units)
* 3) Scale the statically calibrated values with a linear
* dynamically obtained factor
*
* Note: the static sensor offset is the number the sensor outputs
* at a nominally 'zero' input. Therefore the offset has to
* be subtracted.
*
* Example: A gyro outputs a value of 74 at zero angular rate
* the offset is 74 from the origin and subtracting
* 74 from all measurements centers them around zero.
*/
report->timestamp = hrt_absolute_time();
/* swap x and y and negate y */
report->x_raw = raw_report.y;
report->y_raw = ((raw_report.x == -32768) ? 32767 : -raw_report.x);
report->z_raw = raw_report.z;
report->x = ((report->x_raw * _gyro_range_scale) - _gyro_scale.x_offset) * _gyro_scale.x_scale;
report->y = ((report->y_raw * _gyro_range_scale) - _gyro_scale.y_offset) * _gyro_scale.y_scale;
report->z = ((report->z_raw * _gyro_range_scale) - _gyro_scale.z_offset) * _gyro_scale.z_scale;
report->scaling = _gyro_range_scale;
report->range_rad_s = _gyro_range_rad_s;
/* post a report to the ring - note, not locked */
INCREMENT(_next_report, _num_reports);
/* if we are running up against the oldest report, fix it */
if (_next_report == _oldest_report)
INCREMENT(_oldest_report, _num_reports);
/* notify anyone waiting for data */
poll_notify(POLLIN);
/* publish for subscribers */
orb_publish(ORB_ID(sensor_gyro), _gyro_topic, report);
/* stop the perf counter */
perf_end(_sample_perf);
}
void
L3GD20::print_info()
{
perf_print_counter(_sample_perf);
printf("report queue: %u (%u/%u @ %p)\n",
_num_reports, _oldest_report, _next_report, _reports);
}
/**
* Local functions in support of the shell command.
*/
namespace l3gd20
{
L3GD20 *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 L3GD20(1 /* XXX magic number */, GYRO_DEVICE_PATH, (spi_dev_e)PX4_SPIDEV_GYRO);
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(GYRO_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_gyro = -1;
struct gyro_report g_report;
ssize_t sz;
/* get the driver */
fd_gyro = open(GYRO_DEVICE_PATH, O_RDONLY);
if (fd_gyro < 0)
err(1, "%s open failed", GYRO_DEVICE_PATH);
/* reset to manual polling */
if (ioctl(fd_gyro, SENSORIOCSPOLLRATE, SENSOR_POLLRATE_MANUAL) < 0)
err(1, "reset to manual polling");
/* do a simple demand read */
sz = read(fd_gyro, &g_report, sizeof(g_report));
if (sz != sizeof(g_report))
err(1, "immediate gyro read failed");
warnx("gyro x: \t% 9.5f\trad/s", (double)g_report.x);
warnx("gyro y: \t% 9.5f\trad/s", (double)g_report.y);
warnx("gyro z: \t% 9.5f\trad/s", (double)g_report.z);
warnx("gyro x: \t%d\traw", (int)g_report.x_raw);
warnx("gyro y: \t%d\traw", (int)g_report.y_raw);
warnx("gyro z: \t%d\traw", (int)g_report.z_raw);
warnx("gyro range: %8.4f rad/s (%d deg/s)", (double)g_report.range_rad_s,
(int)((g_report.range_rad_s / M_PI_F) * 180.0f + 0.5f));
/* XXX add poll-rate tests here too */
reset();
errx(0, "PASS");
}
/**
* Reset the driver.
*/
void
reset()
{
int fd = open(GYRO_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, "driver not running\n");
printf("state @ %p\n", g_dev);
g_dev->print_info();
exit(0);
}
} // namespace
int
l3gd20_main(int argc, char *argv[])
{
/*
* Start/load the driver.
*/
if (!strcmp(argv[1], "start"))
l3gd20::start();
/*
* Test the driver/device.
*/
if (!strcmp(argv[1], "test"))
l3gd20::test();
/*
* Reset the driver.
*/
if (!strcmp(argv[1], "reset"))
l3gd20::reset();
/*
* Print driver information.
*/
if (!strcmp(argv[1], "info"))
l3gd20::info();
errx(1, "unrecognized command, try 'start', 'test', 'reset' or 'info'");
}