LL40LS driver: adding new range finder driver

This commit is contained in:
akdslr 2014-04-15 20:50:31 -04:00 committed by Lorenz Meier
parent 1b555f2d2e
commit 36a9123822
2 changed files with 920 additions and 0 deletions

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/****************************************************************************
*
* 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 ll40ls.cpp
* @author Allyson Kreft
*
* Driver for the PulsedLight Lidar-Lite 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 LL40LS_BUS PX4_I2C_BUS_EXPANSION
#define LL40LS_BASEADDR 0x42 /* 7-bit address */
#define LL40LS_DEVICE_PATH "/dev/ll40ls"
/* LL40LS Registers addresses */
#define LL40LS_MEASURE_REG 0x00 /* Measure range register */
#define LL40LS_MSRREG_ACQUIRE 0x61 /* Value to initiate a measurement */
#define LL40LS_DISTHIGH_REG 0x8F /* High byte of distance register, auto increment */
/* Device limits */
#define LL40LS_MIN_DISTANCE (0.00f)
#define LL40LS_MAX_DISTANCE (14.00f)
#define LL40LS_CONVERSION_INTERVAL 60000 /* 60ms */
/* 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 LL40LS : public device::I2C
{
public:
LL40LS(int bus = LL40LS_BUS, int address = LL40LS_BASEADDR);
virtual ~LL40LS();
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 LL40LS_MIN_DISTANCE
* and LL40LS_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);
};
/*
* Driver 'main' command.
*/
extern "C" __EXPORT int ll40ls_main(int argc, char *argv[]);
LL40LS::LL40LS(int bus, int address) :
I2C("LL40LS", LL40LS_DEVICE_PATH, bus, address, 100000),
_min_distance(LL40LS_MIN_DISTANCE),
_max_distance(LL40LS_MAX_DISTANCE),
_reports(nullptr),
_sensor_ok(false),
_measure_ticks(0),
_collect_phase(false),
_range_finder_topic(-1),
_class_instance(-1),
_sample_perf(perf_alloc(PC_ELAPSED, "ll40ls_read")),
_comms_errors(perf_alloc(PC_COUNT, "ll40ls_comms_errors")),
_buffer_overflows(perf_alloc(PC_COUNT, "ll40ls_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));
}
LL40LS::~LL40LS()
{
/* 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_DEVICE_PATH, _class_instance);
}
// free perf counters
perf_free(_sample_perf);
perf_free(_comms_errors);
perf_free(_buffer_overflows);
}
int
LL40LS::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_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
LL40LS::probe()
{
return measure();
}
void
LL40LS::set_minimum_distance(float min)
{
_min_distance = min;
}
void
LL40LS::set_maximum_distance(float max)
{
_max_distance = max;
}
float
LL40LS::get_minimum_distance()
{
return _min_distance;
}
float
LL40LS::get_maximum_distance()
{
return _max_distance;
}
int
LL40LS::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(LL40LS_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(LL40LS_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
LL40LS::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(LL40LS_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
LL40LS::measure()
{
int ret;
/*
* Send the command to begin a measurement.
*/
const uint8_t cmd[2] = { LL40LS_MEASURE_REG, LL40LS_MSRREG_ACQUIRE };
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
LL40LS::collect()
{
int ret = -EIO;
/* read from the sensor */
uint8_t val[2] = {0, 0};
perf_begin(_sample_perf);
// read the high and low byte distance registers
uint8_t distance_reg = LL40LS_DISTHIGH_REG;
ret = transfer(&distance_reg, 1, &val[0], sizeof(val));
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 * 1.0f) / 100.0f; /* cm 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;
if (si_units > get_minimum_distance() && si_units < get_maximum_distance()) {
report.valid = 1;
}
else {
report.valid = 0;
}
/* publish it */
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
LL40LS::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)&LL40LS::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
LL40LS::stop()
{
work_cancel(HPWORK, &_work);
}
void
LL40LS::cycle_trampoline(void *arg)
{
LL40LS *dev = (LL40LS *)arg;
dev->cycle();
}
void
LL40LS::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(LL40LS_CONVERSION_INTERVAL)) {
/* schedule a fresh cycle call when we are ready to measure again */
work_queue(HPWORK,
&_work,
(worker_t)&LL40LS::cycle_trampoline,
this,
_measure_ticks - USEC2TICK(LL40LS_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)&LL40LS::cycle_trampoline,
this,
USEC2TICK(LL40LS_CONVERSION_INTERVAL));
}
void
LL40LS::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 ll40ls
{
/* oddly, ERROR is not defined for c++ */
#ifdef ERROR
# undef ERROR
#endif
const int ERROR = -1;
LL40LS *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 LL40LS(LL40LS_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(LL40LS_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(LL40LS_DEVICE_PATH, O_RDONLY);
if (fd < 0) {
err(1, "%s open failed (try 'll40ls start' if the driver is not running", LL40LS_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 5x and report each value */
for (unsigned i = 0; i < 5; 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("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(LL40LS_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
ll40ls_main(int argc, char *argv[])
{
/*
* Start/load the driver.
*/
if (!strcmp(argv[1], "start")) {
ll40ls::start();
}
/*
* Stop the driver
*/
if (!strcmp(argv[1], "stop")) {
ll40ls::stop();
}
/*
* Test the driver/device.
*/
if (!strcmp(argv[1], "test")) {
ll40ls::test();
}
/*
* Reset the driver.
*/
if (!strcmp(argv[1], "reset")) {
ll40ls::reset();
}
/*
* Print driver information.
*/
if (!strcmp(argv[1], "info") || !strcmp(argv[1], "status")) {
ll40ls::info();
}
errx(1, "unrecognized command, try 'start', 'test', 'reset' or 'info'");
}

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############################################################################
#
# 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.
#
############################################################################
#
# Makefile to build the PulsedLight Lidar-Lite driver.
#
MODULE_COMMAND = ll40ls
SRCS = ll40ls.cpp