/****************************************************************************
*
* 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 trone.cpp
* @author Luis Rodrigues
*
* Driver for the TeraRanger One range finders 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_range_finder.h>
#include <drivers/device/ringbuffer.h>
#include <uORB/uORB.h>
#include <uORB/topics/subsystem_info.h>
#include <board_config.h>
/* Configuration Constants */
#define TRONE_BUS PX4_I2C_BUS_EXPANSION
#define TRONE_BASEADDR 0x30 /* 7-bit address */
#define TRONE_DEVICE_PATH "/dev/trone"
/* TRONE Registers addresses */
#define TRONE_MEASURE_REG 0x00 /* Measure range register */
#define TRONE_WHO_AM_I_REG 0x01 /* Who am I test register */
#define TRONE_WHO_AM_I_REG_VAL 0xA1
/* Device limits */
#define TRONE_MIN_DISTANCE (0.20f)
#define TRONE_MAX_DISTANCE (14.00f)
#define TRONE_CONVERSION_INTERVAL 50000 /* 50ms */
/* 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
class TRONE : public device::I2C
{
public:
TRONE(int bus = TRONE_BUS, int address = TRONE_BASEADDR);
virtual ~TRONE();
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:
float _min_distance;
float _max_distance;
work_s _work;
RingBuffer *_reports;
bool _sensor_ok;
int _measure_ticks;
bool _collect_phase;
int _class_instance;
orb_advert_t _range_finder_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();
/**
* Set the min and max distance thresholds if you want the end points of the sensors
* range to be brought in at all, otherwise it will use the defaults TRONE_MIN_DISTANCE
* and TRONE_MAX_DISTANCE
*/
void set_minimum_distance(float min);
void set_maximum_distance(float max);
float get_minimum_distance();
float get_maximum_distance();
/**
* 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);
};
static const uint8_t crc_table[] = {
0x00, 0x07, 0x0e, 0x09, 0x1c, 0x1b, 0x12, 0x15, 0x38, 0x3f, 0x36, 0x31,
0x24, 0x23, 0x2a, 0x2d, 0x70, 0x77, 0x7e, 0x79, 0x6c, 0x6b, 0x62, 0x65,
0x48, 0x4f, 0x46, 0x41, 0x54, 0x53, 0x5a, 0x5d, 0xe0, 0xe7, 0xee, 0xe9,
0xfc, 0xfb, 0xf2, 0xf5, 0xd8, 0xdf, 0xd6, 0xd1, 0xc4, 0xc3, 0xca, 0xcd,
0x90, 0x97, 0x9e, 0x99, 0x8c, 0x8b, 0x82, 0x85, 0xa8, 0xaf, 0xa6, 0xa1,
0xb4, 0xb3, 0xba, 0xbd, 0xc7, 0xc0, 0xc9, 0xce, 0xdb, 0xdc, 0xd5, 0xd2,
0xff, 0xf8, 0xf1, 0xf6, 0xe3, 0xe4, 0xed, 0xea, 0xb7, 0xb0, 0xb9, 0xbe,
0xab, 0xac, 0xa5, 0xa2, 0x8f, 0x88, 0x81, 0x86, 0x93, 0x94, 0x9d, 0x9a,
0x27, 0x20, 0x29, 0x2e, 0x3b, 0x3c, 0x35, 0x32, 0x1f, 0x18, 0x11, 0x16,
0x03, 0x04, 0x0d, 0x0a, 0x57, 0x50, 0x59, 0x5e, 0x4b, 0x4c, 0x45, 0x42,
0x6f, 0x68, 0x61, 0x66, 0x73, 0x74, 0x7d, 0x7a, 0x89, 0x8e, 0x87, 0x80,
0x95, 0x92, 0x9b, 0x9c, 0xb1, 0xb6, 0xbf, 0xb8, 0xad, 0xaa, 0xa3, 0xa4,
0xf9, 0xfe, 0xf7, 0xf0, 0xe5, 0xe2, 0xeb, 0xec, 0xc1, 0xc6, 0xcf, 0xc8,
0xdd, 0xda, 0xd3, 0xd4, 0x69, 0x6e, 0x67, 0x60, 0x75, 0x72, 0x7b, 0x7c,
0x51, 0x56, 0x5f, 0x58, 0x4d, 0x4a, 0x43, 0x44, 0x19, 0x1e, 0x17, 0x10,
0x05, 0x02, 0x0b, 0x0c, 0x21, 0x26, 0x2f, 0x28, 0x3d, 0x3a, 0x33, 0x34,
0x4e, 0x49, 0x40, 0x47, 0x52, 0x55, 0x5c, 0x5b, 0x76, 0x71, 0x78, 0x7f,
0x6a, 0x6d, 0x64, 0x63, 0x3e, 0x39, 0x30, 0x37, 0x22, 0x25, 0x2c, 0x2b,
0x06, 0x01, 0x08, 0x0f, 0x1a, 0x1d, 0x14, 0x13, 0xae, 0xa9, 0xa0, 0xa7,
0xb2, 0xb5, 0xbc, 0xbb, 0x96, 0x91, 0x98, 0x9f, 0x8a, 0x8d, 0x84, 0x83,
0xde, 0xd9, 0xd0, 0xd7, 0xc2, 0xc5, 0xcc, 0xcb, 0xe6, 0xe1, 0xe8, 0xef,
0xfa, 0xfd, 0xf4, 0xf3
};
static uint8_t crc8(uint8_t *p, uint8_t len) {
uint16_t i;
uint16_t crc = 0x0;
while (len--) {
i = (crc ^ *p++) & 0xFF;
crc = (crc_table[i] ^ (crc << 8)) & 0xFF;
}
return crc & 0xFF;
}
/*
* Driver 'main' command.
*/
extern "C" __EXPORT int trone_main(int argc, char *argv[]);
TRONE::TRONE(int bus, int address) :
I2C("TRONE", TRONE_DEVICE_PATH, bus, address, 100000),
_min_distance(TRONE_MIN_DISTANCE),
_max_distance(TRONE_MAX_DISTANCE),
_reports(nullptr),
_sensor_ok(false),
_measure_ticks(0),
_collect_phase(false),
_class_instance(-1),
_range_finder_topic(-1),
_sample_perf(perf_alloc(PC_ELAPSED, "trone_read")),
_comms_errors(perf_alloc(PC_COUNT, "trone_comms_errors")),
_buffer_overflows(perf_alloc(PC_COUNT, "trone_buffer_overflows"))
{
// up the retries since the device misses the first measure attempts
I2C::_retries = 3;
// enable debug() calls
_debug_enabled = false;
// work_cancel in the dtor will explode if we don't do this...
memset(&_work, 0, sizeof(_work));
}
TRONE::~TRONE()
{
/* make sure we are truly inactive */
stop();
/* free any existing reports */
if (_reports != nullptr) {
delete _reports;
}
if (_class_instance != -1) {
unregister_class_devname(RANGE_FINDER_BASE_DEVICE_PATH, _class_instance);
}
// free perf counters
perf_free(_sample_perf);
perf_free(_comms_errors);
perf_free(_buffer_overflows);
}
int
TRONE::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(range_finder_report));
if (_reports == nullptr) {
goto out;
}
_class_instance = register_class_devname(RANGE_FINDER_BASE_DEVICE_PATH);
if (_class_instance == CLASS_DEVICE_PRIMARY) {
/* get a publish handle on the range finder topic */
struct range_finder_report rf_report;
measure();
_reports->get(&rf_report);
_range_finder_topic = orb_advertise(ORB_ID(sensor_range_finder), &rf_report);
if (_range_finder_topic < 0) {
debug("failed to create sensor_range_finder object. Did you start uOrb?");
}
}
ret = OK;
/* sensor is ok, but we don't really know if it is within range */
_sensor_ok = true;
out:
return ret;
}
int
TRONE::probe()
{
uint8_t who_am_i=0;
const uint8_t cmd = TRONE_WHO_AM_I_REG;
if (transfer(&cmd, 1, &who_am_i, 1) == OK && who_am_i == TRONE_WHO_AM_I_REG_VAL) {
// it is responding correctly to a WHO_AM_I
return measure();
}
debug("WHO_AM_I byte mismatch 0x%02x should be 0x%02x\n",
(unsigned)who_am_i,
TRONE_WHO_AM_I_REG_VAL);
// not found on any address
return -EIO;
}
void
TRONE::set_minimum_distance(float min)
{
_min_distance = min;
}
void
TRONE::set_maximum_distance(float max)
{
_max_distance = max;
}
float
TRONE::get_minimum_distance()
{
return _min_distance;
}
float
TRONE::get_maximum_distance()
{
return _max_distance;
}
int
TRONE::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(TRONE_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(TRONE_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;
case RANGEFINDERIOCSETMINIUMDISTANCE: {
set_minimum_distance(*(float *)arg);
return 0;
}
break;
case RANGEFINDERIOCSETMAXIUMDISTANCE: {
set_maximum_distance(*(float *)arg);
return 0;
}
break;
default:
/* give it to the superclass */
return I2C::ioctl(filp, cmd, arg);
}
}
ssize_t
TRONE::read(struct file *filp, char *buffer, size_t buflen)
{
unsigned count = buflen / sizeof(struct range_finder_report);
struct range_finder_report *rbuf = reinterpret_cast<struct range_finder_report *>(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;
}
/* wait for it to complete */
usleep(TRONE_CONVERSION_INTERVAL);
/* 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
TRONE::measure()
{
int ret;
/*
* Send the command to begin a measurement.
*/
const uint8_t cmd = TRONE_MEASURE_REG;
ret = transfer(&cmd, sizeof(cmd), nullptr, 0);
if (OK != ret) {
perf_count(_comms_errors);
log("i2c::transfer returned %d", ret);
return ret;
}
ret = OK;
return ret;
}
int
TRONE::collect()
{
int ret = -EIO;
/* read from the sensor */
uint8_t val[3] = {0, 0, 0};
perf_begin(_sample_perf);
ret = transfer(nullptr, 0, &val[0], 3);
if (ret < 0) {
log("error reading from sensor: %d", ret);
perf_count(_comms_errors);
perf_end(_sample_perf);
return ret;
}
uint16_t distance = (val[0] << 8) | val[1];
float si_units = distance * 0.001f; /* mm to m */
struct range_finder_report report;
/* this should be fairly close to the end of the measurement, so the best approximation of the time */
report.timestamp = hrt_absolute_time();
report.error_count = perf_event_count(_comms_errors);
report.distance = si_units;
report.minimum_distance = get_minimum_distance();
report.maximum_distance = get_maximum_distance();
report.valid = crc8(val, 2) == val[2] && si_units > get_minimum_distance() && si_units < get_maximum_distance() ? 1 : 0;
/* publish it, if we are the primary */
if (_range_finder_topic >= 0) {
orb_publish(ORB_ID(sensor_range_finder), _range_finder_topic, &report);
}
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
TRONE::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)&TRONE::cycle_trampoline, this, 1);
/* notify about state change */
struct subsystem_info_s info = {
true,
true,
true,
SUBSYSTEM_TYPE_RANGEFINDER
};
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
TRONE::stop()
{
work_cancel(HPWORK, &_work);
}
void
TRONE::cycle_trampoline(void *arg)
{
TRONE *dev = (TRONE *)arg;
dev->cycle();
}
void
TRONE::cycle()
{
/* collection phase? */
if (_collect_phase) {
/* perform collection */
if (OK != collect()) {
log("collection error");
/* restart the measurement state machine */
start();
return;
}
/* next phase is measurement */
_collect_phase = false;
/*
* Is there a collect->measure gap?
*/
if (_measure_ticks > USEC2TICK(TRONE_CONVERSION_INTERVAL)) {
/* schedule a fresh cycle call when we are ready to measure again */
work_queue(HPWORK,
&_work,
(worker_t)&TRONE::cycle_trampoline,
this,
_measure_ticks - USEC2TICK(TRONE_CONVERSION_INTERVAL));
return;
}
}
/* measurement phase */
if (OK != measure()) {
log("measure error");
}
/* next phase is collection */
_collect_phase = true;
/* schedule a fresh cycle call when the measurement is done */
work_queue(HPWORK,
&_work,
(worker_t)&TRONE::cycle_trampoline,
this,
USEC2TICK(TRONE_CONVERSION_INTERVAL));
}
void
TRONE::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 trone
{
/* oddly, ERROR is not defined for c++ */
#ifdef ERROR
# undef ERROR
#endif
const int ERROR = -1;
TRONE *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 TRONE(TRONE_BUS);
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(TRONE_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");
}
/**
* 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 range_finder_report report;
ssize_t sz;
int ret;
int fd = open(TRONE_DEVICE_PATH, O_RDONLY);
if (fd < 0) {
err(1, "%s open failed (try 'trone start' if the driver is not running", TRONE_DEVICE_PATH);
}
/* do a simple demand read */
sz = read(fd, &report, sizeof(report));
if (sz != sizeof(report)) {
err(1, "immediate read failed");
}
warnx("single read");
warnx("measurement: %0.2f m", (double)report.distance);
warnx("time: %lld", report.timestamp);
/* start the sensor polling at 2Hz */
if (OK != ioctl(fd, SENSORIOCSPOLLRATE, 2)) {
errx(1, "failed to set 2Hz poll rate");
}
/* read the sensor 50x and report each value */
for (unsigned i = 0; i < 50; 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("valid %u", report.valid);
warnx("measurement: %0.3f", (double)report.distance);
warnx("time: %lld", report.timestamp);
}
/* reset the sensor polling to default rate */
if (OK != ioctl(fd, SENSORIOCSPOLLRATE, SENSOR_POLLRATE_DEFAULT)) {
errx(1, "failed to set default poll rate");
}
errx(0, "PASS");
}
/**
* Reset the driver.
*/
void
reset()
{
int fd = open(TRONE_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
trone_main(int argc, char *argv[])
{
/*
* Start/load the driver.
*/
if (!strcmp(argv[1], "start")) {
trone::start();
}
/*
* Stop the driver
*/
if (!strcmp(argv[1], "stop")) {
trone::stop();
}
/*
* Test the driver/device.
*/
if (!strcmp(argv[1], "test")) {
trone::test();
}
/*
* Reset the driver.
*/
if (!strcmp(argv[1], "reset")) {
trone::reset();
}
/*
* Print driver information.
*/
if (!strcmp(argv[1], "info") || !strcmp(argv[1], "status")) {
trone::info();
}
errx(1, "unrecognized command, try 'start', 'test', 'reset' or 'info'");
}