move all distance sensor drivers to the same folder

src/drivers/distance_sensor/ll40ls/CMakeLists.txt

@@ -0,0 +1,45 @@
+############################################################################
+#
+#   Copyright (c) 2015 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.
+#
+############################################################################
+px4_add_module(
+	MODULE drivers__ll40ls
+	MAIN ll40ls
+	COMPILE_FLAGS
+	SRCS
+		ll40ls.cpp
+		LidarLite.cpp
+		LidarLiteI2C.cpp
+		LidarLitePWM.cpp
+	DEPENDS
+		platforms__common
+	)
+# vim: set noet ft=cmake fenc=utf-8 ff=unix :

src/drivers/distance_sensor/ll40ls/LidarLite.cpp

@@ -0,0 +1,157 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2014, 2015 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 LidarLite.h
+ * @author Johan Jansen <jnsn.johan@gmail.com>
+ *
+ * Generic interface driver for the PulsedLight Lidar-Lite range finders.
+ */
+
+#include "LidarLite.h"
+
+LidarLite::LidarLite() :
+	_min_distance(LL40LS_MIN_DISTANCE),
+	_max_distance(LL40LS_MAX_DISTANCE),
+	_measure_ticks(0)
+{
+}
+
+LidarLite::~LidarLite()
+{
+}
+
+void LidarLite::set_minimum_distance(const float min)
+{
+	_min_distance = min;
+}
+
+void LidarLite::set_maximum_distance(const float max)
+{
+	_max_distance = max;
+}
+
+float LidarLite::get_minimum_distance() const
+{
+	return _min_distance;
+}
+
+float LidarLite::get_maximum_distance() const
+{
+	return _max_distance;
+}
+
+uint32_t LidarLite::getMeasureTicks() const
+{
+	return _measure_ticks;
+}
+
+int LidarLite::ioctl(device::file_t *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 SENSORIOCRESET:
+		reset_sensor();
+		return OK;
+
+	default:
+		return -EINVAL;
+	}
+}

src/drivers/distance_sensor/ll40ls/LidarLite.h

@@ -0,0 +1,107 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2014, 2015 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 LidarLite.h
+ * @author Johan Jansen <jnsn.johan@gmail.com>
+ *
+ * Generic interface driver for the PulsedLight Lidar-Lite range finders.
+ */
+#pragma once
+
+#include <drivers/device/device.h>
+#include <drivers/drv_range_finder.h>
+
+/* Device limits */
+#define LL40LS_MIN_DISTANCE (0.05f)
+#define LL40LS_MAX_DISTANCE (25.00f)
+
+// normal conversion wait time
+#define LL40LS_CONVERSION_INTERVAL 50*1000UL /* 50ms */
+
+// maximum time to wait for a conversion to complete.
+#define LL40LS_CONVERSION_TIMEOUT 100*1000UL /* 100ms */
+
+class LidarLite
+{
+public:
+	LidarLite();
+
+	virtual ~LidarLite();
+
+	virtual int init() = 0;
+
+	virtual int ioctl(device::file_t *filp, int cmd, unsigned long arg);
+
+	virtual void start() = 0;
+
+	virtual void stop() = 0;
+
+	/**
+	* @brief
+	*   Diagnostics - print some basic information about the driver.
+	*/
+	virtual void print_info() = 0;
+
+	/**
+	 * @brief
+	 *   print registers to console
+	 */
+	virtual void print_registers() = 0;
+
+	virtual const char *get_dev_name() = 0;
+
+protected:
+	/**
+	* 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(const float min);
+	void                set_maximum_distance(const float max);
+	float               get_minimum_distance() const;
+	float               get_maximum_distance() const;
+
+	uint32_t            getMeasureTicks() const;
+
+	virtual int         measure() = 0;
+	virtual int         collect() = 0;
+
+	virtual int         reset_sensor() = 0;
+
+private:
+	float               _min_distance;
+	float               _max_distance;
+	uint32_t            _measure_ticks;
+};

src/drivers/distance_sensor/ll40ls/LidarLiteI2C.cpp

@@ -0,0 +1,565 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2014, 2015 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 LidarLiteI2C.cpp
+ * @author Allyson Kreft
+ *
+ * Driver for the PulsedLight Lidar-Lite range finders connected via I2C.
+ */
+
+#include "LidarLiteI2C.h"
+#include <px4_defines.h>
+#include <semaphore.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <poll.h>
+#include <string.h>
+#include <stdio.h>
+#include <drivers/drv_hrt.h>
+
+LidarLiteI2C::LidarLiteI2C(int bus, const char *path, uint8_t rotation, int address) :
+	I2C("LL40LS", path, bus, address, 100000),
+	_rotation(rotation),
+	_work{},
+	_reports(nullptr),
+	_sensor_ok(false),
+	_collect_phase(false),
+	_class_instance(-1),
+	_orb_class_instance(-1),
+	_distance_sensor_topic(nullptr),
+	_sample_perf(perf_alloc(PC_ELAPSED, "ll40ls_i2c_read")),
+	_comms_errors(perf_alloc(PC_COUNT, "ll40ls_i2c_comms_errors")),
+	_sensor_resets(perf_alloc(PC_COUNT, "ll40ls_i2c_resets")),
+	_sensor_zero_resets(perf_alloc(PC_COUNT, "ll40ls_i2c_zero_resets")),
+	_last_distance(0),
+	_zero_counter(0),
+	_acquire_time_usec(0),
+	_pause_measurements(false),
+	_hw_version(0),
+	_sw_version(0)
+{
+	// up the retries since the device misses the first measure attempts
+	_retries = 3;
+
+	// work_cancel in the dtor will explode if we don't do this...
+	memset(&_work, 0, sizeof(_work));
+}
+
+LidarLiteI2C::~LidarLiteI2C()
+{
+	/* 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(_sensor_resets);
+	perf_free(_sensor_zero_resets);
+}
+
+int LidarLiteI2C::init()
+{
+	int ret = PX4_ERROR;
+
+	/* do I2C init (and probe) first */
+	if (I2C::init() != OK) {
+		return ret;
+	}
+
+	/* allocate basic report buffers */
+	_reports = new ringbuffer::RingBuffer(2, sizeof(struct distance_sensor_s));
+
+	if (_reports == nullptr) {
+		return ret;
+	}
+
+	_class_instance = register_class_devname(RANGE_FINDER_BASE_DEVICE_PATH);
+
+	/* get a publish handle on the range finder topic */
+	struct distance_sensor_s ds_report = {};
+	measure();
+	_reports->get(&ds_report);
+	_distance_sensor_topic = orb_advertise_multi(ORB_ID(distance_sensor), &ds_report,
+				 &_orb_class_instance, ORB_PRIO_LOW);
+
+	if (_distance_sensor_topic == nullptr) {
+		DEVICE_DEBUG("failed to create distance_sensor object. Did you start uOrb?");
+	}
+
+	ret = OK;
+	/* sensor is ok, but we don't really know if it is within range */
+	_sensor_ok = true;
+
+	return ret;
+}
+
+int LidarLiteI2C::read_reg(uint8_t reg, uint8_t &val)
+{
+	return lidar_transfer(&reg, 1, &val, 1);
+}
+
+int LidarLiteI2C::write_reg(uint8_t reg, uint8_t val)
+{
+	const uint8_t cmd[2] = { reg, val };
+	return transfer(&cmd[0], 2, nullptr, 0);
+}
+
+/*
+  LidarLite specific transfer() function that avoids a stop condition
+  with SCL low
+ */
+int LidarLiteI2C::lidar_transfer(const uint8_t *send, unsigned send_len, uint8_t *recv, unsigned recv_len)
+{
+	if (send != nullptr && send_len > 0) {
+		int ret = transfer(send, send_len, nullptr, 0);
+
+		if (ret != OK) {
+			return ret;
+		}
+	}
+
+	if (recv != nullptr && recv_len > 0) {
+		return transfer(nullptr, 0, recv, recv_len);
+	}
+
+	return OK;
+}
+
+int LidarLiteI2C::probe()
+{
+	// cope with both old and new I2C bus address
+	const uint8_t addresses[2] = {LL40LS_BASEADDR, LL40LS_BASEADDR_OLD};
+
+	// more retries for detection
+	_retries = 10;
+
+	for (uint8_t i = 0; i < sizeof(addresses); i++) {
+		/*
+		  check for hw and sw versions. It would be better if
+		  we had a proper WHOAMI register
+		 */
+		if (read_reg(LL40LS_HW_VERSION, _hw_version) == OK && _hw_version > 0 &&
+		    read_reg(LL40LS_SW_VERSION, _sw_version) == OK && _sw_version > 0) {
+			goto ok;
+		}
+
+		DEVICE_DEBUG("probe failed hw_version=0x%02x sw_version=0x%02x\n",
+			     (unsigned)_hw_version,
+			     (unsigned)_sw_version);
+	}
+
+	// not found on any address
+	return -EIO;
+
+ok:
+	_retries = 3;
+	return reset_sensor();
+}
+
+int LidarLiteI2C::ioctl(device::file_t *filp, int cmd, unsigned long arg)
+{
+	switch (cmd) {
+	case SENSORIOCSQUEUEDEPTH: {
+			/* lower bound is mandatory, upper bound is a sanity check */
+			if ((arg < 1) || (arg > 100)) {
+				return -EINVAL;
+			}
+
+			ATOMIC_ENTER;
+
+			if (!_reports->resize(arg)) {
+				ATOMIC_LEAVE;
+				return -ENOMEM;
+			}
+
+			ATOMIC_LEAVE;
+
+			return OK;
+		}
+
+	default: {
+			int result = LidarLite::ioctl(filp, cmd, arg);
+
+			if (result == -EINVAL) {
+				result = I2C::ioctl(filp, cmd, arg);
+			}
+
+			return result;
+		}
+	}
+}
+
+ssize_t LidarLiteI2C::read(device::file_t *filp, char *buffer, size_t buflen)
+{
+	unsigned count = buflen / sizeof(struct distance_sensor_s);
+	struct distance_sensor_s *rbuf = reinterpret_cast<struct distance_sensor_s *>(buffer);
+	int ret = 0;
+
+	/* buffer must be large enough */
+	if (count < 1) {
+		return -ENOSPC;
+	}
+
+	/* if automatic measurement is enabled */
+	if (getMeasureTicks() > 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 LidarLiteI2C::measure()
+{
+	int ret;
+
+	if (_pause_measurements) {
+		// we are in print_registers() and need to avoid
+		// acquisition to keep the I2C peripheral on the
+		// sensor active
+		return OK;
+	}
+
+	/*
+	 * Send the command to begin a measurement.
+	 */
+	const uint8_t cmd[2] = { LL40LS_MEASURE_REG, LL40LS_MSRREG_ACQUIRE };
+	ret = lidar_transfer(cmd, sizeof(cmd), nullptr, 0);
+
+	if (OK != ret) {
+		perf_count(_comms_errors);
+		DEVICE_DEBUG("i2c::transfer returned %d", ret);
+
+		// if we are getting lots of I2C transfer errors try
+		// resetting the sensor
+		if (perf_event_count(_comms_errors) % 10 == 0) {
+			perf_count(_sensor_resets);
+			reset_sensor();
+		}
+
+		return ret;
+	}
+
+	// remember when we sent the acquire so we can know when the
+	// acquisition has timed out
+	_acquire_time_usec = hrt_absolute_time();
+	ret = OK;
+
+	return ret;
+}
+
+/*
+  reset the sensor to power on defaults
+ */
+int LidarLiteI2C::reset_sensor()
+{
+	int ret = write_reg(LL40LS_MEASURE_REG, LL40LS_MSRREG_RESET);
+
+	if (ret != OK) {
+		return ret;
+	}
+
+	// wait for sensor reset to complete
+	usleep(1000);
+
+	return OK;
+}
+
+/*
+  dump sensor registers for debugging
+ */
+void LidarLiteI2C::print_registers()
+{
+	_pause_measurements = true;
+	printf("ll40ls registers\n");
+	// wait for a while to ensure the lidar is in a ready state
+	usleep(50000);
+
+	for (uint8_t reg = 0; reg <= 0x67; reg++) {
+		uint8_t val = 0;
+		int ret = lidar_transfer(&reg, 1, &val, 1);
+
+		if (ret != OK) {
+			printf("%02x:XX ", (unsigned)reg);
+
+		} else {
+			printf("%02x:%02x ", (unsigned)reg, (unsigned)val);
+		}
+
+		if (reg % 16 == 15) {
+			printf("\n");
+		}
+	}
+
+	printf("\n");
+	_pause_measurements = false;
+}
+
+int LidarLiteI2C::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 | LL40LS_AUTO_INCREMENT;
+	ret = lidar_transfer(&distance_reg, 1, &val[0], sizeof(val));
+
+	// if the transfer failed or if the high bit of distance is
+	// set then the distance is invalid
+	if (ret < 0 || (val[0] & 0x80)) {
+		if (hrt_absolute_time() - _acquire_time_usec > LL40LS_CONVERSION_TIMEOUT) {
+			/*
+			  NACKs from the sensor are expected when we
+			  read before it is ready, so only consider it
+			  an error if more than 100ms has elapsed.
+			 */
+			DEVICE_DEBUG("error reading from sensor: %d", ret);
+			perf_count(_comms_errors);
+
+			if (perf_event_count(_comms_errors) % 10 == 0) {
+				perf_count(_sensor_resets);
+				reset_sensor();
+			}
+		}
+
+		perf_end(_sample_perf);
+		// if we are getting lots of I2C transfer errors try
+		// resetting the sensor
+		return ret;
+	}
+
+	uint16_t distance_cm = (val[0] << 8) | val[1];
+	float distance_m = float(distance_cm) * 1e-2f;
+	struct distance_sensor_s report;
+
+	if (distance_cm == 0) {
+		_zero_counter++;
+
+		if (_zero_counter == 20) {
+			/* we have had 20 zeros in a row - reset the
+			   sensor. This is a known bad state of the
+			   sensor where it returns 16 bits of zero for
+			   the distance with a trailing NACK, and
+			   keeps doing that even when the target comes
+			   into a valid range.
+			*/
+			_zero_counter = 0;
+			perf_end(_sample_perf);
+			perf_count(_sensor_zero_resets);
+			return reset_sensor();
+		}
+
+	} else {
+		_zero_counter = 0;
+	}
+
+	_last_distance = distance_cm;
+
+
+	/* this should be fairly close to the end of the measurement, so the best approximation of the time */
+	report.timestamp = hrt_absolute_time();
+	report.current_distance = distance_m;
+	report.min_distance = get_minimum_distance();
+	report.max_distance = get_maximum_distance();
+	report.covariance = 0.0f;
+	/* the sensor is in fact a laser + sonar but there is no enum for this */
+	report.type = distance_sensor_s::MAV_DISTANCE_SENSOR_LASER;
+	report.orientation = _rotation;
+	/* TODO: set proper ID */
+	report.id = 0;
+
+	/* publish it, if we are the primary */
+	if (_distance_sensor_topic != nullptr) {
+		orb_publish(ORB_ID(distance_sensor), _distance_sensor_topic, &report);
+	}
+
+	_reports->force(&report);
+
+	/* notify anyone waiting for data */
+	poll_notify(POLLIN);
+
+	ret = OK;
+
+	perf_end(_sample_perf);
+	return ret;
+}
+
+void LidarLiteI2C::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)&LidarLiteI2C::cycle_trampoline, this, 1);
+}
+
+void LidarLiteI2C::stop()
+{
+	work_cancel(HPWORK, &_work);
+}
+
+void LidarLiteI2C::cycle_trampoline(void *arg)
+{
+	LidarLiteI2C *dev = (LidarLiteI2C *)arg;
+
+	dev->cycle();
+}
+
+void LidarLiteI2C::cycle()
+{
+	/* collection phase? */
+	if (_collect_phase) {
+
+		/* try a collection */
+		if (OK != collect()) {
+			DEVICE_DEBUG("collection error");
+
+			/* if we've been waiting more than 200ms then
+			   send a new acquire */
+			if (hrt_absolute_time() - _acquire_time_usec > LL40LS_CONVERSION_TIMEOUT * 2) {
+				_collect_phase = false;
+			}
+
+		} else {
+			/* next phase is measurement */
+			_collect_phase = false;
+
+			/*
+			 * Is there a collect->measure gap?
+			 */
+			if (getMeasureTicks() > USEC2TICK(LL40LS_CONVERSION_INTERVAL)) {
+
+				/* schedule a fresh cycle call when we are ready to measure again */
+				work_queue(HPWORK,
+					   &_work,
+					   (worker_t)&LidarLiteI2C::cycle_trampoline,
+					   this,
+					   getMeasureTicks() - USEC2TICK(LL40LS_CONVERSION_INTERVAL));
+
+				return;
+			}
+		}
+	}
+
+	if (_collect_phase == false) {
+		/* measurement phase */
+		if (OK != measure()) {
+			DEVICE_DEBUG("measure error");
+
+		} else {
+			/* next phase is collection. Don't switch to
+			   collection phase until we have a successful
+			   acquire request I2C transfer */
+			_collect_phase = true;
+		}
+	}
+
+	/* schedule a fresh cycle call when the measurement is done */
+	work_queue(HPWORK,
+		   &_work,
+		   (worker_t)&LidarLiteI2C::cycle_trampoline,
+		   this,
+		   USEC2TICK(LL40LS_CONVERSION_INTERVAL));
+}
+
+void LidarLiteI2C::print_info()
+{
+	perf_print_counter(_sample_perf);
+	perf_print_counter(_comms_errors);
+	perf_print_counter(_sensor_resets);
+	perf_print_counter(_sensor_zero_resets);
+	printf("poll interval:  %u ticks\n", getMeasureTicks());
+	_reports->print_info("report queue");
+	printf("distance: %ucm (0x%04x)\n",
+	       (unsigned)_last_distance, (unsigned)_last_distance);
+}
+
+const char *LidarLiteI2C::get_dev_name()
+{
+	return get_devname();
+}

src/drivers/distance_sensor/ll40ls/LidarLiteI2C.h

@@ -0,0 +1,179 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2014, 2015 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 LidarLiteI2C.h
+ * @author Allyson Kreft
+ *
+ * Driver for the PulsedLight Lidar-Lite range finders connected via I2C.
+ */
+
+#pragma once
+
+#include "LidarLite.h"
+
+#include <px4_workqueue.h>
+
+#include <systemlib/perf_counter.h>
+
+#include <drivers/device/i2c.h>
+#include <drivers/device/ringbuffer.h>
+
+#include <uORB/uORB.h>
+#include <uORB/topics/distance_sensor.h>
+
+
+/* Configuration Constants */
+#define LL40LS_BASEADDR     0x62 /* 7-bit address */
+#define LL40LS_BASEADDR_OLD     0x42 /* previous 7-bit address */
+
+/* LL40LS Registers addresses */
+
+#define LL40LS_MEASURE_REG      0x00        /* Measure range register */
+#define LL40LS_MSRREG_RESET     0x00        /* reset to power on defaults */
+#define LL40LS_MSRREG_ACQUIRE       0x04        /* Value to initiate a measurement, varies based on sensor revision */
+#define LL40LS_DISTHIGH_REG     0x0F        /* High byte of distance register, auto increment */
+#define LL40LS_AUTO_INCREMENT   0x80
+#define LL40LS_HW_VERSION         0x41
+#define LL40LS_SW_VERSION         0x4f
+#define LL40LS_SIGNAL_STRENGTH_REG  0x5b
+
+class LidarLiteI2C : public LidarLite, public device::I2C
+{
+public:
+	LidarLiteI2C(int bus, const char *path,
+		     uint8_t rotation = distance_sensor_s::ROTATION_DOWNWARD_FACING,
+		     int address = LL40LS_BASEADDR);
+	virtual ~LidarLiteI2C();
+
+	int         init() override;
+
+	ssize_t     read(device::file_t *filp, char *buffer, size_t buflen) override;
+	int         ioctl(device::file_t *filp, int cmd, unsigned long arg) override;
+
+	/**
+	* Diagnostics - print some basic information about the driver.
+	*/
+	void print_info() override;
+
+	/**
+	 * print registers to console
+	 */
+	void print_registers() override;
+
+	const char *get_dev_name() override;
+
+protected:
+	int         probe() override;
+	int         read_reg(uint8_t reg, uint8_t &val);
+	int         write_reg(uint8_t reg, uint8_t val);
+
+	int                 measure() override;
+	int                 reset_sensor() override;
+
+private:
+	uint8_t _rotation;
+	work_s              _work;
+	ringbuffer::RingBuffer          *_reports;
+	bool                _sensor_ok;
+	bool                _collect_phase;
+	int                 _class_instance;
+	int		    _orb_class_instance;
+
+	orb_advert_t        _distance_sensor_topic;
+
+	perf_counter_t      _sample_perf;
+	perf_counter_t      _comms_errors;
+	perf_counter_t      _sensor_resets;
+	perf_counter_t      _sensor_zero_resets;
+	uint16_t        _last_distance;
+	uint16_t        _zero_counter;
+	uint64_t        _acquire_time_usec;
+	volatile bool       _pause_measurements;
+	uint8_t		_hw_version;
+	uint8_t		_sw_version;
+
+	/**
+	 * LidarLite specific transfer function. This is needed
+	 * to avoid a stop transition with SCL high
+	 *
+	 * @param send		Pointer to bytes to send.
+	 * @param send_len	Number of bytes to send.
+	 * @param recv		Pointer to buffer for bytes received.
+	 * @param recv_len	Number of bytes to receive.
+	 * @return		OK if the transfer was successful, -errno
+	 *			otherwise.
+	 */
+	int lidar_transfer(const uint8_t *send, unsigned send_len, uint8_t *recv, unsigned recv_len);
+
+	/**
+	* 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() override;
+
+	/**
+	* Stop the automatic measurement state machine.
+	*/
+	void                stop() override;
+
+	/**
+	* Perform a poll cycle; collect from the previous measurement
+	* and start a new one.
+	*/
+	void                cycle();
+	int                 collect() override;
+
+	/**
+	* 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);
+
+private:
+	LidarLiteI2C(const LidarLiteI2C &copy) = delete;
+	LidarLiteI2C operator=(const LidarLiteI2C &assignment) = delete;
+};

src/drivers/distance_sensor/ll40ls/LidarLitePWM.cpp

@@ -0,0 +1,289 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2014, 2015 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 LidarLitePWM.h
+ * @author Johan Jansen <jnsn.johan@gmail.com>
+ * @author Ban Siesta <bansiesta@gmail.com>
+ *
+ * Driver for the PulsedLight Lidar-Lite range finders connected via PWM.
+ *
+ * This driver accesses the pwm_input published by the pwm_input driver.
+ */
+
+#include "LidarLitePWM.h"
+#include <stdio.h>
+#include <string.h>
+#include <px4_defines.h>
+#include <drivers/drv_hrt.h>
+#include <drivers/drv_pwm_input.h>
+
+LidarLitePWM::LidarLitePWM(const char *path, uint8_t rotation) :
+	CDev("LidarLitePWM", path),
+	_rotation(rotation),
+	_work{},
+	_reports(nullptr),
+	_class_instance(-1),
+	_orb_class_instance(-1),
+	_pwmSub(-1),
+	_pwm{},
+	_distance_sensor_topic(nullptr),
+	_range{},
+	_sample_perf(perf_alloc(PC_ELAPSED, "ll40ls_pwm_read")),
+	_read_errors(perf_alloc(PC_COUNT, "ll40ls_pwm_read_errors")),
+	_sensor_zero_resets(perf_alloc(PC_COUNT, "ll40ls_pwm_zero_resets"))
+{
+}
+
+LidarLitePWM::~LidarLitePWM()
+{
+	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(_sensor_zero_resets);
+}
+
+
+int LidarLitePWM::init()
+{
+	/* do regular cdev init */
+	int ret = CDev::init();
+
+	if (ret != PX4_OK) {
+		return PX4_ERROR;
+	}
+
+	/* allocate basic report buffers */
+	_reports = new ringbuffer::RingBuffer(2, sizeof(struct distance_sensor_s));
+
+	if (_reports == nullptr) {
+		return PX4_ERROR;
+	}
+
+	_class_instance = register_class_devname(RANGE_FINDER_BASE_DEVICE_PATH);
+
+	/* get a publish handle on the distance_sensor topic */
+	struct distance_sensor_s ds_report = {};
+	measure();
+	_reports->get(&ds_report);
+	_distance_sensor_topic = orb_advertise_multi(ORB_ID(distance_sensor), &ds_report,
+				 &_orb_class_instance, ORB_PRIO_LOW);
+
+	if (_distance_sensor_topic == nullptr) {
+		DEVICE_DEBUG("failed to create distance_sensor object. Did you start uOrb?");
+	}
+
+	return PX4_OK;
+}
+
+void LidarLitePWM::print_info()
+{
+	perf_print_counter(_sample_perf);
+	perf_print_counter(_read_errors);
+	perf_print_counter(_sensor_zero_resets);
+	warnx("poll interval:  %u ticks", getMeasureTicks());
+	warnx("distance: %.3fm", (double)_range.current_distance);
+}
+
+void LidarLitePWM::print_registers()
+{
+	printf("Not supported in PWM mode\n");
+}
+
+void LidarLitePWM::start()
+{
+	/* schedule a cycle to start things */
+	work_queue(HPWORK, &_work, (worker_t)&LidarLitePWM::cycle_trampoline, this, 1);
+}
+
+void LidarLitePWM::stop()
+{
+	work_cancel(HPWORK, &_work);
+}
+
+void LidarLitePWM::cycle_trampoline(void *arg)
+{
+	LidarLitePWM *dev = (LidarLitePWM *)arg;
+
+	dev->cycle();
+}
+
+void LidarLitePWM::cycle()
+{
+	measure();
+
+	/* schedule a fresh cycle call when the measurement is done */
+	work_queue(HPWORK,
+		   &_work,
+		   (worker_t)&LidarLitePWM::cycle_trampoline,
+		   this,
+		   getMeasureTicks());
+}
+
+int LidarLitePWM::measure()
+{
+	perf_begin(_sample_perf);
+
+	if (PX4_OK != collect()) {
+		DEVICE_DEBUG("collection error");
+		perf_count(_read_errors);
+		perf_end(_sample_perf);
+		return PX4_ERROR;
+	}
+
+	_range.timestamp = hrt_absolute_time();
+	_range.type = distance_sensor_s::MAV_DISTANCE_SENSOR_LASER;
+	_range.max_distance = get_maximum_distance();
+	_range.min_distance = get_minimum_distance();
+	_range.current_distance = float(_pwm.pulse_width) * 1e-3f;   /* 10 usec = 1 cm distance for LIDAR-Lite */
+	_range.covariance = 0.0f;
+	_range.orientation = _rotation;
+	/* TODO: set proper ID */
+	_range.id = 0;
+
+	/* Due to a bug in older versions of the LidarLite firmware, we have to reset sensor on (distance == 0) */
+	if (_range.current_distance <= 0.0f) {
+		perf_count(_sensor_zero_resets);
+		perf_end(_sample_perf);
+		return reset_sensor();
+	}
+
+	if (_distance_sensor_topic != nullptr) {
+		orb_publish(ORB_ID(distance_sensor), _distance_sensor_topic, &_range);
+	}
+
+	_reports->force(&_range);
+
+	poll_notify(POLLIN);
+	perf_end(_sample_perf);
+	return PX4_OK;
+}
+
+ssize_t LidarLitePWM::read(device::file_t *filp, char *buffer, size_t buflen)
+{
+	unsigned count = buflen / sizeof(struct distance_sensor_s);
+	struct distance_sensor_s *rbuf = reinterpret_cast<struct distance_sensor_s *>(buffer);
+	int ret = 0;
+
+	/* buffer must be large enough */
+	if (count < 1) {
+		return -ENOSPC;
+	}
+
+	/* if automatic measurement is enabled */
+	if (getMeasureTicks() > 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;
+
+	} else {
+
+		_reports->flush();
+		measure();
+
+		if (_reports->get(rbuf)) {
+			ret = sizeof(*rbuf);
+		}
+	}
+
+	return ret;
+}
+
+int
+LidarLitePWM::ioctl(device::file_t *filp, int cmd, unsigned long arg)
+{
+	switch (cmd) {
+	/* no custom ioctls implemented for now */
+	default:
+		/* give it to the superclass */
+		return LidarLite::ioctl(filp, cmd, arg);
+	}
+}
+
+int LidarLitePWM::collect()
+{
+	int fd = ::open(PWMIN0_DEVICE_PATH, O_RDONLY);
+
+	if (fd == -1) {
+		return PX4_ERROR;
+	}
+
+	if (::read(fd, &_pwm, sizeof(_pwm)) == sizeof(_pwm)) {
+		::close(fd);
+		return PX4_OK;
+	}
+
+	::close(fd);
+	return EAGAIN;
+}
+
+int LidarLitePWM::reset_sensor()
+{
+
+	int fd = ::open(PWMIN0_DEVICE_PATH, O_RDONLY);
+
+	if (fd == -1) {
+		return PX4_ERROR;
+	}
+
+	int ret = ::ioctl(fd, SENSORIOCRESET, 0);
+	::close(fd);
+	return ret;
+}
+
+const char *LidarLitePWM::get_dev_name()
+{
+	return get_devname();
+}

src/drivers/distance_sensor/ll40ls/LidarLitePWM.h

@@ -0,0 +1,123 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2014, 2015 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 LidarLitePWM.h
+ * @author Johan Jansen <jnsn.johan@gmail.com>
+ * @author Ban Siesta <bansiesta@gmail.com>
+ *
+ * Driver for the PulsedLight Lidar-Lite range finders connected via PWM.
+ *
+ * This driver accesses the pwm_input published by the pwm_input driver.
+ */
+#pragma once
+
+#include "LidarLite.h"
+
+#include <px4_workqueue.h>
+
+
+#include <drivers/device/ringbuffer.h>
+#include <systemlib/perf_counter.h>
+
+#include <uORB/uORB.h>
+#include <uORB/topics/pwm_input.h>
+#include <uORB/topics/distance_sensor.h>
+
+
+
+class LidarLitePWM : public LidarLite, public device::CDev
+{
+public:
+	LidarLitePWM(const char *path, uint8_t rotation = distance_sensor_s::ROTATION_DOWNWARD_FACING);
+	virtual ~LidarLitePWM();
+
+	int init() override;
+
+	ssize_t read(device::file_t *filp, char *buffer, size_t buflen) override;
+	int	ioctl(device::file_t *filp, int cmd, unsigned long arg) override;
+
+	void start() override;
+
+	void stop() override;
+
+	void cycle();
+
+	/**
+	* @brief
+	*   Diagnostics - print some basic information about the driver.
+	*/
+	void print_info() override;
+
+	/**
+	 * @brief
+	 *   print registers to console
+	 */
+	void print_registers() override;
+
+	/**
+	* 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);
+
+	const char *get_dev_name() override;
+
+protected:
+
+	int measure() override;
+
+	int collect() override;
+
+	int reset_sensor() override;
+
+	void task_main_trampoline(int argc, char *argv[]);
+
+private:
+	uint8_t _rotation;
+	work_s			_work;
+	ringbuffer::RingBuffer	*_reports;
+	int			_class_instance;
+	int			_orb_class_instance;
+	int			_pwmSub;
+	struct pwm_input_s	_pwm;
+	orb_advert_t	        _distance_sensor_topic;
+	struct distance_sensor_s _range;
+
+	perf_counter_t	        _sample_perf;
+	perf_counter_t	        _read_errors;
+	perf_counter_t	        _sensor_zero_resets;
+};

src/drivers/distance_sensor/ll40ls/ll40ls.cpp

@@ -0,0 +1,425 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2014, 2015 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
+ * @author Johan Jansen <jnsn.johan@gmail.com>
+ * @author Ban Siesta <bansiesta@gmail.com>
+ * @author James Goppert <james.goppert@gmail.com>
+ *
+ * Interface for the PulsedLight Lidar-Lite range finders.
+ */
+
+#include "LidarLiteI2C.h"
+#include "LidarLitePWM.h"
+#include <board_config.h>
+#include <systemlib/err.h>
+#include <fcntl.h>
+#include <cstdlib>
+#include <string.h>
+#include <stdio.h>
+#include <platforms/px4_getopt.h>
+
+#ifndef CONFIG_SCHED_WORKQUEUE
+# error This requires CONFIG_SCHED_WORKQUEUE.
+#endif
+
+#define LL40LS_DEVICE_PATH_PWM  "/dev/ll40ls_pwm"
+
+enum LL40LS_BUS {
+	LL40LS_BUS_I2C_ALL = 0,
+	LL40LS_BUS_I2C_INTERNAL,
+	LL40LS_BUS_I2C_EXTERNAL,
+	LL40LS_BUS_PWM
+};
+
+static struct ll40ls_bus_option {
+	enum LL40LS_BUS busid;
+	const char *devname;
+	uint8_t busnum;
+} bus_options[] = {
+#ifdef PX4_I2C_BUS_EXPANSION
+	{ LL40LS_BUS_I2C_EXTERNAL, "/dev/ll40ls_ext", PX4_I2C_BUS_EXPANSION },
+#endif
+#ifdef PX4_I2C_BUS_EXPANSION1
+	{ LL40LS_BUS_I2C_EXTERNAL, "/dev/ll40ls_ext1", PX4_I2C_BUS_EXPANSION1 },
+#endif
+#ifdef PX4_I2C_BUS_ONBOARD
+	{ LL40LS_BUS_I2C_INTERNAL, "/dev/ll40ls_int", PX4_I2C_BUS_ONBOARD },
+#endif
+};
+
+/*
+ * Driver 'main' command.
+ */
+extern "C" __EXPORT int ll40ls_main(int argc, char *argv[]);
+
+
+/**
+ * Local functions in support of the shell command.
+ */
+namespace ll40ls
+{
+
+LidarLite *instance = nullptr;
+
+void	start(enum LL40LS_BUS busid, uint8_t rotation);
+void	stop();
+void	test();
+void	reset();
+void	info();
+void	regdump();
+void	usage();
+
+/**
+ * Start the driver.
+ */
+void start(enum LL40LS_BUS busid, uint8_t rotation)
+{
+	int fd, ret;
+
+	if (instance) {
+		PX4_INFO("driver already started");
+	}
+
+	if (busid == LL40LS_BUS_PWM) {
+		instance = new LidarLitePWM(LL40LS_DEVICE_PATH_PWM, rotation);
+
+		if (!instance) {
+			PX4_ERR("Failed to instantiate LidarLitePWM");
+			return;
+		}
+
+		if (instance->init() != PX4_OK) {
+			PX4_ERR("failed to initialize LidarLitePWM");
+			goto fail;
+		}
+
+	} else {
+		for (uint8_t i = 0; i < (sizeof(bus_options) / sizeof(bus_options[0])); i++) {
+			if (busid != LL40LS_BUS_I2C_ALL && busid != bus_options[i].busid) {
+				continue;
+			}
+
+			instance = new LidarLiteI2C(bus_options[i].busnum, bus_options[i].devname, rotation);
+
+			if (!instance) {
+				PX4_ERR("Failed to instantiate LidarLiteI2C");
+				return;
+			}
+
+			if (instance->init() == PX4_OK) {
+				break;
+			}
+
+			PX4_ERR("failed to initialize LidarLiteI2C on busnum=%u", bus_options[i].busnum);
+			delete instance;
+			instance = nullptr;
+		}
+	}
+
+	if (!instance) {
+		PX4_WARN("No LidarLite found");
+		return;
+	}
+
+	fd = px4_open(instance->get_dev_name(), O_RDONLY);
+
+	if (fd == -1) {
+		PX4_ERR("Error opening fd");
+		goto fail;
+	}
+
+	ret = px4_ioctl(fd, SENSORIOCSPOLLRATE, SENSOR_POLLRATE_DEFAULT);
+	px4_close(fd);
+
+	if (ret < 0) {
+		PX4_ERR("pollrate fail");
+		goto fail;
+	}
+
+	return;
+
+fail:
+	delete instance;
+	instance = nullptr;
+}
+
+/**
+ * Stop the driver
+ */
+void stop()
+{
+	delete instance;
+	instance = nullptr;
+}
+
+/**
+ * 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 distance_sensor_s report;
+	ssize_t sz;
+	int ret;
+
+	if (!instance) {
+		PX4_ERR("No ll40ls driver running");
+		return;
+	}
+
+	int fd = px4_open(instance->get_dev_name(), O_RDONLY);
+
+	if (fd < 0) {
+		PX4_ERR("Error opening fd");
+		return;
+	}
+
+	/* do a simple demand read */
+	sz = px4_read(fd, &report, sizeof(report));
+
+	if (sz != sizeof(report)) {
+		PX4_ERR("immediate read failed");
+		return;
+	}
+
+	PX4_INFO("single read");
+	PX4_INFO("measurement: %0.2f m", (double)report.current_distance);
+	PX4_INFO("time:        %lld", report.timestamp);
+
+	/* start the sensor polling at 2Hz */
+	if (PX4_OK != px4_ioctl(fd, SENSORIOCSPOLLRATE, 2)) {
+		PX4_ERR("failed to set 2Hz poll rate");
+		return;
+	}
+
+	/* read the sensor 5 times and report each value */
+	for (unsigned i = 0; i < 5; i++) {
+		px4_pollfd_struct_t fds;
+
+		/* wait for data to be ready */
+		fds.fd = fd;
+		fds.events = POLLIN;
+		ret = px4_poll(&fds, 1, 2000);
+
+		if (ret != 1) {
+			PX4_WARN("timed out waiting for sensor data");
+			return;
+		}
+
+		/* now go get it */
+		sz = px4_read(fd, &report, sizeof(report));
+
+		if (sz != sizeof(report)) {
+			PX4_WARN("periodic read failed");
+			return;
+		}
+
+		PX4_INFO("periodic read %u", i);
+		PX4_INFO("valid %u", (float)report.current_distance > report.min_distance
+			 && (float)report.current_distance < report.max_distance ? 1 : 0);
+		PX4_INFO("measurement: %0.3f m", (double)report.current_distance);
+		PX4_INFO("time:        %lld", report.timestamp);
+	}
+
+	/* reset the sensor polling to default rate */
+	if (PX4_OK != px4_ioctl(fd, SENSORIOCSPOLLRATE, SENSOR_POLLRATE_DEFAULT)) {
+		PX4_WARN("failed to set default poll rate");
+	}
+
+	px4_close(fd);
+}
+
+/**
+ * Reset the driver.
+ */
+void
+reset()
+{
+	if (!instance) {
+		PX4_WARN("No ll40ls driver running");
+		return;
+	}
+
+	int fd = px4_open(instance->get_dev_name(), O_RDONLY);
+
+	if (fd < 0) {
+		PX4_ERR("Error opening fd");
+		return;
+	}
+
+	if (px4_ioctl(fd, SENSORIOCRESET, 0) < 0) {
+		PX4_ERR("driver reset failed");
+		goto error;
+	}
+
+	if (px4_ioctl(fd, SENSORIOCSPOLLRATE, SENSOR_POLLRATE_DEFAULT) < 0) {
+		PX4_ERR("driver poll restart failed");
+		goto error;
+	}
+
+error:
+	px4_close(fd);
+}
+
+/**
+ * Print a little info about the driver.
+ */
+void
+info()
+{
+	if (!instance) {
+		warnx("No ll40ls driver running");
+		return;
+	}
+
+	printf("state @ %p\n", instance);
+	instance->print_info();
+}
+
+/**
+ * Dump registers
+ */
+void
+regdump()
+{
+	if (!instance) {
+		warnx("No ll40ls driver running");
+		return;
+	}
+
+	printf("regdump @ %p\n", instance);
+	instance->print_registers();
+}
+
+void
+usage()
+{
+	PX4_INFO("missing command: try 'start', 'stop', 'info', 'test', 'reset', 'info' or 'regdump' [i2c|pwm]");
+	PX4_INFO("options for I2C:");
+	PX4_INFO("    -X only external bus");
+#ifdef PX4_I2C_BUS_ONBOARD
+	PX4_INFO("    -I only internal bus");
+#endif
+	PX4_INFO("E.g. ll40ls start i2c -R 0");
+}
+
+} // namespace
+
+int
+ll40ls_main(int argc, char *argv[])
+{
+	int ch;
+	int myoptind = 1;
+	const char *myoptarg = nullptr;
+	enum LL40LS_BUS busid = LL40LS_BUS_I2C_ALL;
+	uint8_t rotation = distance_sensor_s::ROTATION_DOWNWARD_FACING;
+
+	while ((ch = px4_getopt(argc, argv, "IXR:", &myoptind, &myoptarg)) != EOF) {
+		switch (ch) {
+#ifdef PX4_I2C_BUS_ONBOARD
+
+		case 'I':
+			busid = LL40LS_BUS_I2C_INTERNAL;
+			break;
+#endif
+
+		case 'X':
+			busid = LL40LS_BUS_I2C_EXTERNAL;
+			break;
+
+		case 'R':
+			rotation = (uint8_t)atoi(myoptarg);
+			PX4_INFO("Setting Lidar orientation to %d", (int)rotation);
+			break;
+
+		default:
+			ll40ls::usage();
+			return 0;
+		}
+	}
+
+	/* determine protocol first because it's needed next */
+	if (argc > myoptind + 1) {
+		const char *protocol = argv[myoptind + 1];
+
+		if (!strcmp(protocol, "pwm")) {
+			busid = LL40LS_BUS_PWM;;
+
+		} else if (!strcmp(protocol, "i2c")) {
+			// Do nothing
+
+		} else {
+			warnx("unknown protocol, choose pwm or i2c");
+			ll40ls::usage();
+			return 0;
+		}
+	}
+
+	/* now determine action */
+	if (argc > myoptind) {
+		const char *verb = argv[myoptind];
+
+		if (!strcmp(verb, "start")) {
+			ll40ls::start(busid, rotation);
+
+		} else if (!strcmp(verb, "stop")) {
+			ll40ls::stop();
+
+		} else if (!strcmp(verb, "test")) {
+			ll40ls::test();
+
+		} else if (!strcmp(verb, "reset")) {
+			ll40ls::reset();
+
+		} else if (!strcmp(verb, "regdump")) {
+			ll40ls::regdump();
+
+		} else if (!strcmp(verb, "info") || !strcmp(verb, "status")) {
+			ll40ls::info();
+
+		} else {
+			ll40ls::usage();
+		}
+
+		return 0;
+	}
+
+	warnx("unrecognized command, try 'start', 'test', 'reset', 'info' or 'regdump'");
+	ll40ls::usage();
+	return 0;
+}