/****************************************************************************
*
* Copyright (c) 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 px4flow.cpp
* @author Dominik Honegger
*
* Driver for the PX4FLOW module connected via I2C.
*/
#include <nuttx/config.h>
#include <drivers/device/i2c.h>
#include <sys/types.h>
#include <stdint.h>
#include <stdlib.h>
#include <stdbool.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 <nuttx/arch.h>
#include <nuttx/wqueue.h>
#include <nuttx/clock.h>
#include <systemlib/perf_counter.h>
#include <systemlib/err.h>
#include <drivers/drv_hrt.h>
#include <drivers/drv_px4flow.h>
#include <drivers/device/ringbuffer.h>
#include <uORB/uORB.h>
#include <uORB/topics/subsystem_info.h>
#include <uORB/topics/optical_flow.h>
#include <board_config.h>
/* Configuration Constants */
#define I2C_FLOW_ADDRESS 0x42 //* 7-bit address. 8-bit address is 0x84
//range 0x42 - 0x49
/* PX4FLOW Registers addresses */
#define PX4FLOW_REG 0x16 /* Measure Register 22*/
#define PX4FLOW_CONVERSION_INTERVAL 20000 //in microseconds! 20000 = 50 Hz 100000 = 10Hz
/* oddly, ERROR is not defined for c++ */
#ifdef ERROR
# undef ERROR
#endif
static const int ERROR = -1;
#ifndef CONFIG_SCHED_WORKQUEUE
# error This requires CONFIG_SCHED_WORKQUEUE.
#endif
struct i2c_frame {
uint16_t frame_count;
int16_t pixel_flow_x_sum;
int16_t pixel_flow_y_sum;
int16_t flow_comp_m_x;
int16_t flow_comp_m_y;
int16_t qual;
int16_t gyro_x_rate;
int16_t gyro_y_rate;
int16_t gyro_z_rate;
uint8_t gyro_range;
uint8_t sonar_timestamp;
int16_t ground_distance;
};
struct i2c_frame f;
typedef struct i2c_integral_frame {
uint16_t frame_count_since_last_readout;
int16_t pixel_flow_x_integral;
int16_t pixel_flow_y_integral;
int16_t gyro_x_rate_integral;
int16_t gyro_y_rate_integral;
int16_t gyro_z_rate_integral;
uint32_t integration_timespan;
uint32_t time_since_last_sonar_update;
uint16_t ground_distance;
uint8_t qual;
} __attribute__((packed));
struct i2c_integral_frame f_integral;
class PX4FLOW: public device::I2C
{
public:
PX4FLOW(int bus, int address = I2C_FLOW_ADDRESS);
virtual ~PX4FLOW();
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:
work_s _work;
RingBuffer *_reports;
bool _sensor_ok;
int _measure_ticks;
bool _collect_phase;
orb_advert_t _px4flow_topic;
perf_counter_t _sample_perf;
perf_counter_t _comms_errors;
perf_counter_t _buffer_overflows;
/**
* Test whether the device supported by the driver is present at a
* specific address.
*
* @param address The I2C bus address to probe.
* @return True if the device is present.
*/
int probe_address(uint8_t address);
/**
* Initialise the automatic measurement state machine and start it.
*
* @note This function is called at open and error time. It might make sense
* to make it more aggressive about resetting the bus in case of errors.
*/
void start();
/**
* Stop the automatic measurement state machine.
*/
void stop();
/**
* Perform a poll cycle; collect from the previous measurement
* and start a new one.
*/
void cycle();
int measure();
int collect();
/**
* Static trampoline from the workq context; because we don't have a
* generic workq wrapper yet.
*
* @param arg Instance pointer for the driver that is polling.
*/
static void cycle_trampoline(void *arg);
};
/*
* Driver 'main' command.
*/
extern "C" __EXPORT int px4flow_main(int argc, char *argv[]);
PX4FLOW::PX4FLOW(int bus, int address) :
I2C("PX4FLOW", PX4FLOW_DEVICE_PATH, bus, address, 400000), //400khz
_reports(nullptr),
_sensor_ok(false),
_measure_ticks(0),
_collect_phase(false),
_px4flow_topic(-1),
_sample_perf(perf_alloc(PC_ELAPSED, "px4flow_read")),
_comms_errors(perf_alloc(PC_COUNT, "px4flow_comms_errors")),
_buffer_overflows(perf_alloc(PC_COUNT, "px4flow_buffer_overflows"))
{
// enable debug() calls
_debug_enabled = true;
// work_cancel in the dtor will explode if we don't do this...
memset(&_work, 0, sizeof(_work));
}
PX4FLOW::~PX4FLOW()
{
/* make sure we are truly inactive */
stop();
/* free any existing reports */
if (_reports != nullptr) {
delete _reports;
}
}
int
PX4FLOW::init()
{
int ret = ERROR;
/* do I2C init (and probe) first */
if (I2C::init() != OK) {
goto out;
}
/* allocate basic report buffers */
_reports = new RingBuffer(2, sizeof(optical_flow_s));
if (_reports == nullptr) {
goto out;
}
ret = OK;
/* sensor is ok, but we don't really know if it is within range */
_sensor_ok = true;
out:
return ret;
}
int
PX4FLOW::probe()
{
uint8_t val[22];
// to be sure this is not a ll40ls Lidar (which can also be on
// 0x42) we check if a 22 byte transfer works from address
// 0. The ll40ls gives an error for that, whereas the flow
// happily returns some data
if (transfer(nullptr, 0, &val[0], 22) != OK) {
return -EIO;
}
// that worked, so start a measurement cycle
return measure();
}
int
PX4FLOW::ioctl(struct file *filp, int cmd, unsigned long arg)
{
switch (cmd) {
case SENSORIOCSPOLLRATE: {
switch (arg) {
/* switching to manual polling */
case SENSOR_POLLRATE_MANUAL:
stop();
_measure_ticks = 0;
return OK;
/* external signalling (DRDY) 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: {
/* do we need to start internal polling? */
bool want_start = (_measure_ticks == 0);
/* set interval for next measurement to minimum legal value */
_measure_ticks = USEC2TICK(PX4FLOW_CONVERSION_INTERVAL);
/* if we need to start the poll state machine, do it */
if (want_start) {
start();
}
return OK;
}
/* adjust to a legal polling interval in Hz */
default: {
/* do we need to start internal polling? */
bool want_start = (_measure_ticks == 0);
/* convert hz to tick interval via microseconds */
unsigned ticks = USEC2TICK(1000000 / arg);
/* check against maximum rate */
if (ticks < USEC2TICK(PX4FLOW_CONVERSION_INTERVAL)) {
return -EINVAL;
}
/* update interval for next measurement */
_measure_ticks = ticks;
/* if we need to start the poll state machine, do it */
if (want_start) {
start();
}
return OK;
}
}
}
case SENSORIOCGPOLLRATE:
if (_measure_ticks == 0) {
return SENSOR_POLLRATE_MANUAL;
}
return (1000 / _measure_ticks);
case SENSORIOCSQUEUEDEPTH: {
/* lower bound is mandatory, upper bound is a sanity check */
if ((arg < 1) || (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 this */
return -EINVAL;
default:
/* give it to the superclass */
return I2C::ioctl(filp, cmd, arg);
}
}
ssize_t
PX4FLOW::read(struct file *filp, char *buffer, size_t buflen)
{
unsigned count = buflen / sizeof(struct optical_flow_s);
struct optical_flow_s *rbuf = reinterpret_cast<struct optical_flow_s *>(buffer);
int ret = 0;
/* buffer must be large enough */
if (count < 1) {
return -ENOSPC;
}
/* if automatic measurement is enabled */
if (_measure_ticks > 0) {
/*
* While there is space in the caller's buffer, and reports, copy them.
* Note that we may be pre-empted by the workq thread while we are doing this;
* we are careful to avoid racing with them.
*/
while (count--) {
if (_reports->get(rbuf)) {
ret += sizeof(*rbuf);
rbuf++;
}
}
/* if there was no data, warn the caller */
return ret ? ret : -EAGAIN;
}
/* manual measurement - run one conversion */
do {
_reports->flush();
/* trigger a measurement */
if (OK != measure()) {
ret = -EIO;
break;
}
/* run the collection phase */
if (OK != collect()) {
ret = -EIO;
break;
}
/* state machine will have generated a report, copy it out */
if (_reports->get(rbuf)) {
ret = sizeof(*rbuf);
}
} while (0);
return ret;
}
int
PX4FLOW::measure()
{
int ret;
/*
* Send the command to begin a measurement.
*/
uint8_t cmd = PX4FLOW_REG;
ret = transfer(&cmd, 1, nullptr, 0);
if (OK != ret) {
perf_count(_comms_errors);
log("i2c::transfer returned %d", ret);
printf("i2c::transfer flow returned %d");
return ret;
}
ret = OK;
return ret;
}
int
PX4FLOW::collect()
{
int ret = -EIO;
/* read from the sensor */
uint8_t val[46] = { 0 };
perf_begin(_sample_perf);
if (PX4FLOW_REG == 0x00) {
ret = transfer(nullptr, 0, &val[0], 45); // read 45 bytes (22+23 : frame1 + frame2)
}
if (PX4FLOW_REG == 0x16) {
ret = transfer(nullptr, 0, &val[0], 23); // read 23 bytes (only frame2)
}
if (ret < 0) {
log("error reading from sensor: %d", ret);
perf_count(_comms_errors);
perf_end(_sample_perf);
return ret;
}
if (PX4FLOW_REG == 0) {
f.frame_count = val[1] << 8 | val[0];
f.pixel_flow_x_sum = val[3] << 8 | val[2];
f.pixel_flow_y_sum = val[5] << 8 | val[4];
f.flow_comp_m_x = val[7] << 8 | val[6];
f.flow_comp_m_y = val[9] << 8 | val[8];
f.qual = val[11] << 8 | val[10];
f.gyro_x_rate = val[13] << 8 | val[12];
f.gyro_y_rate = val[15] << 8 | val[14];
f.gyro_z_rate = val[17] << 8 | val[16];
f.gyro_range = val[18];
f.sonar_timestamp = val[19];
f.ground_distance = val[21] << 8 | val[20];
f_integral.frame_count_since_last_readout = val[23] << 8 | val[22];
f_integral.pixel_flow_x_integral = val[25] << 8 | val[24];
f_integral.pixel_flow_y_integral = val[27] << 8 | val[26];
f_integral.gyro_x_rate_integral = val[29] << 8 | val[28];
f_integral.gyro_y_rate_integral = val[31] << 8 | val[30];
f_integral.gyro_z_rate_integral = val[33] << 8 | val[32];
f_integral.integration_timespan = val[37] << 24 | val[36] << 16
| val[35] << 8 | val[34];
f_integral.time_since_last_sonar_update = val[41] << 24 | val[40] << 16
| val[39] << 8 | val[38];
f_integral.ground_distance = val[43] << 8 | val[42];
f_integral.qual = val[44];
}
if (PX4FLOW_REG == 0x16) {
f_integral.frame_count_since_last_readout = val[1] << 8 | val[0];
f_integral.pixel_flow_x_integral = val[3] << 8 | val[2];
f_integral.pixel_flow_y_integral = val[5] << 8 | val[4];
f_integral.gyro_x_rate_integral = val[7] << 8 | val[6];
f_integral.gyro_y_rate_integral = val[9] << 8 | val[8];
f_integral.gyro_z_rate_integral = val[11] << 8 | val[10];
f_integral.integration_timespan = val[15] << 24 | val[14] << 16 | val[13] << 8 | val[12];
f_integral.time_since_last_sonar_update = val[19] << 24 | val[18] << 16 | val[17] << 8 | val[16];
f_integral.ground_distance = val[21] << 8 | val[20];
f_integral.qual = val[22];
}
struct optical_flow_s report;
report.timestamp = hrt_absolute_time();
report.pixel_flow_x_integral = static_cast<float>(f_integral.pixel_flow_x_integral) / 10000.0f;//convert to radians
report.pixel_flow_y_integral = static_cast<float>(f_integral.pixel_flow_y_integral) / 10000.0f;//convert to radians
report.frame_count_since_last_readout = f_integral.frame_count_since_last_readout;
report.ground_distance_m = static_cast<float>(f_integral.ground_distance) / 1000.0f;//convert to meters
report.quality = f_integral.qual; //0:bad ; 255 max quality
report.gyro_x_rate_integral = static_cast<float>(f_integral.gyro_x_rate_integral) / 10000.0f; //convert to radians
report.gyro_y_rate_integral = static_cast<float>(f_integral.gyro_y_rate_integral) / 10000.0f; //convert to radians
report.gyro_z_rate_integral = static_cast<float>(f_integral.gyro_z_rate_integral) / 10000.0f; //convert to radians
report.integration_timespan = f_integral.integration_timespan; //microseconds
report.time_since_last_sonar_update = f_integral.time_since_last_sonar_update;//microseconds
report.sensor_id = 0;
if (_px4flow_topic < 0) {
_px4flow_topic = orb_advertise(ORB_ID(optical_flow), &report);
} else {
/* publish it */
orb_publish(ORB_ID(optical_flow), _px4flow_topic, &report);
}
/* post a report to the ring */
if (_reports->force(&report)) {
perf_count(_buffer_overflows);
}
/* notify anyone waiting for data */
poll_notify(POLLIN);
ret = OK;
perf_end(_sample_perf);
return ret;
}
void
PX4FLOW::start()
{
/* reset the report ring and state machine */
_collect_phase = false;
_reports->flush();
/* schedule a cycle to start things */
work_queue(HPWORK, &_work, (worker_t)&PX4FLOW::cycle_trampoline, this, 1);
/* notify about state change */
struct subsystem_info_s info = {
true,
true,
true,
SUBSYSTEM_TYPE_OPTICALFLOW
};
static orb_advert_t pub = -1;
if (pub > 0) {
orb_publish(ORB_ID(subsystem_info), pub, &info);
} else {
pub = orb_advertise(ORB_ID(subsystem_info), &info);
}
}
void
PX4FLOW::stop()
{
work_cancel(HPWORK, &_work);
}
void
PX4FLOW::cycle_trampoline(void *arg)
{
PX4FLOW *dev = (PX4FLOW *)arg;
dev->cycle();
}
void
PX4FLOW::cycle()
{
if (OK != measure()) {
log("measure error");
}
/* perform collection */
if (OK != collect()) {
log("collection error");
/* restart the measurement state machine */
start();
return;
}
work_queue(HPWORK, &_work, (worker_t)&PX4FLOW::cycle_trampoline, this,
_measure_ticks);
}
void
PX4FLOW::print_info()
{
perf_print_counter(_sample_perf);
perf_print_counter(_comms_errors);
perf_print_counter(_buffer_overflows);
printf("poll interval: %u ticks\n", _measure_ticks);
_reports->print_info("report queue");
}
/**
* Local functions in support of the shell command.
*/
namespace px4flow
{
/* oddly, ERROR is not defined for c++ */
#ifdef ERROR
# undef ERROR
#endif
const int ERROR = -1;
PX4FLOW *g_dev;
void start();
void stop();
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 PX4FLOW(PX4_I2C_BUS_EXPANSION);
if (g_dev == nullptr) {
goto fail;
}
if (OK != g_dev->init()) {
delete g_dev;
/* try 2nd bus */
g_dev = new PX4FLOW(PX4_I2C_BUS_ESC);
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(PX4FLOW_DEVICE_PATH, O_RDONLY);
if (fd < 0) {
goto fail;
}
if (ioctl(fd, SENSORIOCSPOLLRATE, SENSOR_POLLRATE_MAX) < 0) {
goto fail;
}
exit(0);
fail:
if (g_dev != nullptr) {
delete g_dev;
g_dev = nullptr;
}
errx(1, "driver start failed");
}
/**
* Stop the driver
*/
void
stop()
{
if (g_dev != nullptr) {
delete g_dev;
g_dev = nullptr;
} else {
errx(1, "driver not running");
}
exit(0);
}
/**
* Perform some basic functional tests on the driver;
* make sure we can collect data from the sensor in polled
* and automatic modes.
*/
void
test()
{
struct optical_flow_s report;
ssize_t sz;
int ret;
int fd = open(PX4FLOW_DEVICE_PATH, O_RDONLY);
if (fd < 0) {
err(1, "%s open failed (try 'px4flow start' if the driver is not running", PX4FLOW_DEVICE_PATH);
}
/* do a simple demand read */
sz = read(fd, &report, sizeof(report));
if (sz != sizeof(report))
{
warnx("immediate read failed");
}
warnx("single read");
warnx("flowx: %0.2f m/s", (double) f.pixel_flow_x_sum);
warnx("flowy: %0.2f m/s", (double) f.pixel_flow_y_sum);
warnx("time: %lld", report.timestamp);
/* start the sensor polling at 10Hz */
if (OK != ioctl(fd, SENSORIOCSPOLLRATE, 10)) {
errx(1, "failed to set 10Hz poll rate");
}
/* read the sensor 5x and report each value */
for (unsigned i = 0; i < 10; i++) {
struct pollfd fds;
/* wait for data to be ready */
fds.fd = fd;
fds.events = POLLIN;
ret = poll(&fds, 1, 2000);
if (ret != 1) {
errx(1, "timed out waiting for sensor data");
}
/* now go get it */
sz = read(fd, &report, sizeof(report));
if (sz != sizeof(report)) {
err(1, "periodic read failed");
}
warnx("periodic read %u", i);
warnx("framecount_total: %u", f.frame_count);
warnx("framecount_integral: %u",
f_integral.frame_count_since_last_readout);
warnx("pixel_flow_x_integral: %i", f_integral.pixel_flow_x_integral);
warnx("pixel_flow_y_integral: %i", f_integral.pixel_flow_y_integral);
warnx("gyro_x_rate_integral: %i", f_integral.gyro_x_rate_integral);
warnx("gyro_y_rate_integral: %i", f_integral.gyro_y_rate_integral);
warnx("gyro_z_rate_integral: %i", f_integral.gyro_z_rate_integral);
warnx("integration_timespan [us]: %u", f_integral.integration_timespan);
warnx("ground_distance: %0.2f m",
(double) f_integral.ground_distance / 1000);
warnx("time since last sonar update [us]: %i",
f_integral.time_since_last_sonar_update);
warnx("quality integration average : %i", f_integral.qual);
warnx("quality : %i", f.qual);
}
errx(0, "PASS");
}
/**
* Reset the driver.
*/
void
reset()
{
int fd = open(PX4FLOW_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");
}
printf("state @ %p\n", g_dev);
g_dev->print_info();
exit(0);
}
} // namespace
int
px4flow_main(int argc, char *argv[])
{
/*
* Start/load the driver.
*/
if (!strcmp(argv[1], "start")) {
px4flow::start();
}
/*
* Stop the driver
*/
if (!strcmp(argv[1], "stop")) {
px4flow::stop();
}
/*
* Test the driver/device.
*/
if (!strcmp(argv[1], "test")) {
px4flow::test();
}
/*
* Reset the driver.
*/
if (!strcmp(argv[1], "reset")) {
px4flow::reset();
}
/*
* Print driver information.
*/
if (!strcmp(argv[1], "info") || !strcmp(argv[1], "status")) {
px4flow::info();
}
errx(1, "unrecognized command, try 'start', 'test', 'reset' or 'info'");
}