/**************************************************************************** * * Copyright (c) 2014 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 sf0x.cpp * @author Lorenz Meier * @author Greg Hulands * * Driver for the Lightware SF0x laser rangefinder series */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* Configuration Constants */ /* 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 #define SF0X_CONVERSION_INTERVAL 83334 #define SF0X_TAKE_RANGE_REG 'd' #define SF02F_MIN_DISTANCE 0.0f #define SF02F_MAX_DISTANCE 40.0f #define SF0X_DEFAULT_PORT "/dev/ttyS2" class SF0X : public device::CDev { public: SF0X(const char *port = SF0X_DEFAULT_PORT); virtual ~SF0X(); 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 _fd; char _linebuf[10]; unsigned _linebuf_index; hrt_abstime _last_read; orb_advert_t _range_finder_topic; unsigned _consecutive_fail_count; perf_counter_t _sample_perf; perf_counter_t _comms_errors; perf_counter_t _buffer_overflows; /** * 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 SF0X_MIN_DISTANCE * and SF0X_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 sf0x_main(int argc, char *argv[]); SF0X::SF0X(const char *port) : CDev("SF0X", RANGE_FINDER_DEVICE_PATH), _min_distance(SF02F_MIN_DISTANCE), _max_distance(SF02F_MAX_DISTANCE), _reports(nullptr), _sensor_ok(false), _measure_ticks(0), _collect_phase(false), _fd(-1), _linebuf_index(0), _last_read(0), _range_finder_topic(-1), _consecutive_fail_count(0), _sample_perf(perf_alloc(PC_ELAPSED, "sf0x_read")), _comms_errors(perf_alloc(PC_COUNT, "sf0x_comms_errors")), _buffer_overflows(perf_alloc(PC_COUNT, "sf0x_buffer_overflows")) { /* open fd */ _fd = ::open(port, O_RDWR | O_NOCTTY | O_NONBLOCK); if (_fd < 0) { warnx("FAIL: laser fd"); } /* tell it to stop auto-triggering */ char stop_auto = ' '; (void)::write(_fd, &stop_auto, 1); usleep(100); (void)::write(_fd, &stop_auto, 1); struct termios uart_config; int termios_state; /* fill the struct for the new configuration */ tcgetattr(_fd, &uart_config); /* clear ONLCR flag (which appends a CR for every LF) */ uart_config.c_oflag &= ~ONLCR; /* no parity, one stop bit */ uart_config.c_cflag &= ~(CSTOPB | PARENB); unsigned speed = B9600; /* set baud rate */ if ((termios_state = cfsetispeed(&uart_config, speed)) < 0) { warnx("ERR CFG: %d ISPD", termios_state); } if ((termios_state = cfsetospeed(&uart_config, speed)) < 0) { warnx("ERR CFG: %d OSPD\n", termios_state); } if ((termios_state = tcsetattr(_fd, TCSANOW, &uart_config)) < 0) { warnx("ERR baud %d ATTR", termios_state); } // disable debug() calls _debug_enabled = false; // work_cancel in the dtor will explode if we don't do this... memset(&_work, 0, sizeof(_work)); } SF0X::~SF0X() { /* make sure we are truly inactive */ stop(); /* free any existing reports */ if (_reports != nullptr) { delete _reports; } } int SF0X::init() { /* do regular cdev init */ if (CDev::init() != OK) { goto out; } /* allocate basic report buffers */ _reports = new RingBuffer(2, sizeof(range_finder_report)); if (_reports == nullptr) { warnx("mem err"); goto out; } /* get a publish handle on the range finder topic */ struct range_finder_report zero_report; memset(&zero_report, 0, sizeof(zero_report)); _range_finder_topic = orb_advertise(ORB_ID(sensor_range_finder), &zero_report); if (_range_finder_topic < 0) { warnx("advert err"); } /* close the fd */ ::close(_fd); _fd = -1; out: return OK; } int SF0X::probe() { return measure(); } void SF0X::set_minimum_distance(float min) { _min_distance = min; } void SF0X::set_maximum_distance(float max) { _max_distance = max; } float SF0X::get_minimum_distance() { return _min_distance; } float SF0X::get_maximum_distance() { return _max_distance; } int SF0X::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(SF0X_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(SF0X_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 CDev::ioctl(filp, cmd, arg); } } ssize_t SF0X::read(struct file *filp, char *buffer, size_t buflen) { unsigned count = buflen / sizeof(struct range_finder_report); struct range_finder_report *rbuf = reinterpret_cast(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(SF0X_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 SF0X::measure() { int ret; /* * Send the command to begin a measurement. */ char cmd = SF0X_TAKE_RANGE_REG; ret = ::write(_fd, &cmd, 1); if (ret != sizeof(cmd)) { perf_count(_comms_errors); log("write fail %d", ret); return ret; } ret = OK; return ret; } int SF0X::collect() { int ret; perf_begin(_sample_perf); /* clear buffer if last read was too long ago */ uint64_t read_elapsed = hrt_elapsed_time(&_last_read); if (read_elapsed > (SF0X_CONVERSION_INTERVAL * 2)) { _linebuf_index = 0; } else if (_linebuf_index > 0) { /* increment to next read position */ _linebuf_index++; } /* the buffer for read chars is buflen minus null termination */ unsigned readlen = sizeof(_linebuf) - 1; /* read from the sensor (uart buffer) */ ret = ::read(_fd, &_linebuf[_linebuf_index], readlen - _linebuf_index); if (ret < 0) { _linebuf[sizeof(_linebuf) - 1] = '\0'; debug("read err: %d lbi: %d buf: %s", ret, (int)_linebuf_index, _linebuf); perf_count(_comms_errors); perf_end(_sample_perf); /* only throw an error if we time out */ if (read_elapsed > (SF0X_CONVERSION_INTERVAL * 2)) { return ret; } else { return -EAGAIN; } } else if (ret == 0) { return -EAGAIN; } /* we did increment the index to the next position already, so just add the additional fields */ _linebuf_index += (ret - 1); _last_read = hrt_absolute_time(); if (_linebuf_index < 1) { /* we need at least the two end bytes to make sense of this string */ return -EAGAIN; } else if (_linebuf[_linebuf_index - 1] != '\r' || _linebuf[_linebuf_index] != '\n') { if (_linebuf_index >= readlen - 1) { /* we have a full buffer, but no line ending - abort */ _linebuf_index = 0; perf_count(_comms_errors); return -ENOMEM; } else { /* incomplete read, reschedule ourselves */ return -EAGAIN; } } char *end; float si_units; bool valid; /* enforce line ending */ unsigned lend = (_linebuf_index < (sizeof(_linebuf) - 1)) ? _linebuf_index : (sizeof(_linebuf) - 1); _linebuf[lend] = '\0'; if (_linebuf[0] == '-' && _linebuf[1] == '-' && _linebuf[2] == '.') { si_units = -1.0f; valid = false; } else { /* we need to find a dot in the string, as we're missing the meters part else */ valid = false; /* wipe out partially read content from last cycle(s), check for dot */ for (unsigned i = 0; i < (lend - 2); i++) { if (_linebuf[i] == '\n') { char buf[sizeof(_linebuf)]; memcpy(buf, &_linebuf[i+1], (lend + 1) - (i + 1)); memcpy(_linebuf, buf, (lend + 1) - (i + 1)); } if (_linebuf[i] == '.') { valid = true; } } if (valid) { si_units = strtod(_linebuf, &end); /* we require at least 3 characters for a valid number */ if (end > _linebuf + 3) { valid = true; } else { si_units = -1.0f; valid = false; } } } debug("val (float): %8.4f, raw: %s, valid: %s\n", (double)si_units, _linebuf, ((valid) ? "OK" : "NO")); /* done with this chunk, resetting - even if invalid */ _linebuf_index = 0; /* if its invalid, there is no reason to forward the value */ if (!valid) { perf_count(_comms_errors); return -EINVAL; } 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.valid = valid && (si_units > get_minimum_distance() && si_units < get_maximum_distance() ? 1 : 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 SF0X::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)&SF0X::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 SF0X::stop() { work_cancel(HPWORK, &_work); } void SF0X::cycle_trampoline(void *arg) { SF0X *dev = static_cast(arg); dev->cycle(); } void SF0X::cycle() { /* fds initialized? */ if (_fd < 0) { /* open fd */ _fd = ::open(SF0X_DEFAULT_PORT, O_RDWR | O_NOCTTY | O_NONBLOCK); } /* collection phase? */ if (_collect_phase) { /* perform collection */ int collect_ret = collect(); if (collect_ret == -EAGAIN) { /* reschedule to grab the missing bits, time to transmit 10 bytes @9600 bps */ work_queue(HPWORK, &_work, (worker_t)&SF0X::cycle_trampoline, this, USEC2TICK(1100)); return; } if (OK != collect_ret) { /* we know the sensor needs about four seconds to initialize */ if (hrt_absolute_time() > 5 * 1000 * 1000LL && _consecutive_fail_count < 5) { log("collection error #%u", _consecutive_fail_count); } _consecutive_fail_count++; /* restart the measurement state machine */ start(); return; } else { /* apparently success */ _consecutive_fail_count = 0; } /* next phase is measurement */ _collect_phase = false; /* * Is there a collect->measure gap? */ if (_measure_ticks > USEC2TICK(SF0X_CONVERSION_INTERVAL)) { /* schedule a fresh cycle call when we are ready to measure again */ work_queue(HPWORK, &_work, (worker_t)&SF0X::cycle_trampoline, this, _measure_ticks - USEC2TICK(SF0X_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)&SF0X::cycle_trampoline, this, USEC2TICK(SF0X_CONVERSION_INTERVAL)); } void SF0X::print_info() { perf_print_counter(_sample_perf); perf_print_counter(_comms_errors); perf_print_counter(_buffer_overflows); printf("poll interval: %d ticks\n", _measure_ticks); _reports->print_info("report queue"); } /** * Local functions in support of the shell command. */ namespace sf0x { /* oddly, ERROR is not defined for c++ */ #ifdef ERROR # undef ERROR #endif const int ERROR = -1; SF0X *g_dev; void start(const char *port); void stop(); void test(); void reset(); void info(); /** * Start the driver. */ void start(const char *port) { int fd; if (g_dev != nullptr) { errx(1, "already started"); } /* create the driver */ g_dev = new SF0X(port); 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(RANGE_FINDER_DEVICE_PATH, 0); if (fd < 0) { warnx("device open fail"); 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 fd = open(RANGE_FINDER_DEVICE_PATH, O_RDONLY); if (fd < 0) { err(1, "%s open failed (try 'sf0x start' if the driver is not running", RANGE_FINDER_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("val: %0.2f m", (double)report.distance); warnx("time: %lld", report.timestamp); /* start the sensor polling at 2 Hz rate */ 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; int ret = poll(&fds, 1, 2000); if (ret != 1) { warnx("timed out"); break; } /* now go get it */ sz = read(fd, &report, sizeof(report)); if (sz != sizeof(report)) { warnx("read failed: got %d vs exp. %d", sz, sizeof(report)); break; } warnx("read #%u", i); warnx("val: %0.3f m", (double)report.distance); warnx("time: %lld", report.timestamp); } /* reset the sensor polling to the default rate */ if (OK != ioctl(fd, SENSORIOCSPOLLRATE, SENSOR_POLLRATE_DEFAULT)) { errx(1, "ERR: DEF RATE"); } errx(0, "PASS"); } /** * Reset the driver. */ void reset() { int fd = open(RANGE_FINDER_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 sf0x_main(int argc, char *argv[]) { /* * Start/load the driver. */ if (!strcmp(argv[1], "start")) { if (argc > 2) { sf0x::start(argv[2]); } else { sf0x::start(SF0X_DEFAULT_PORT); } } /* * Stop the driver */ if (!strcmp(argv[1], "stop")) { sf0x::stop(); } /* * Test the driver/device. */ if (!strcmp(argv[1], "test")) { sf0x::test(); } /* * Reset the driver. */ if (!strcmp(argv[1], "reset")) { sf0x::reset(); } /* * Print driver information. */ if (!strcmp(argv[1], "info") || !strcmp(argv[1], "status")) { sf0x::info(); } errx(1, "unrecognized command, try 'start', 'test', 'reset' or 'info'"); }