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LidarLite: Code cleanup, prepare for PWM version of the driver

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This commit is contained in:
Johan Jansen
2015-03-24 10:04:40 +01:00
parent fff74304f0
commit b084558a79
4 changed files with 813 additions and 790 deletions
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src/drivers/ll40ls/LidarLiteI2C.cpp
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/****************************************************************************
*
* 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 <nuttx/config.h>
#include "LidarLiteI2C.h"
#include <semaphore.h>
#include <fcntl.h>
#include <errno.h>
#include <poll.h>
#include <string.h>
#include <stdio.h>
#include <drivers/device/ringbuffer.h>
#include <drivers/drv_hrt.h>
/* oddly, ERROR is not defined for c++ */
#ifdef ERROR
# undef ERROR
#endif
static const int ERROR = -1;
LidarLiteI2C::LidarLiteI2C(int bus, const char *path, int address) :
I2C("LL40LS", 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),
_class_instance(-1),
_range_finder_topic(-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")),
_sensor_resets(perf_alloc(PC_COUNT, "ll40ls_resets")),
_sensor_zero_resets(perf_alloc(PC_COUNT, "ll40ls_zero_resets")),
_last_distance(0),
_zero_counter(0),
_pause_measurements(false),
_bus(bus)
{
// up the retries since the device misses the first measure attempts
_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));
}
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(_buffer_overflows);
perf_free(_sensor_resets);
perf_free(_sensor_zero_resets);
}
int LidarLiteI2C::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 LidarLiteI2C::read_reg(uint8_t reg, uint8_t &val)
{
return transfer(&reg, 1, &val, 1);
}
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++) {
uint8_t who_am_i=0, max_acq_count=0;
// set the I2C bus address
set_address(addresses[i]);
/* register 2 defaults to 0x80. If this matches it is
almost certainly a ll40ls */
if (read_reg(LL40LS_MAX_ACQ_COUNT_REG, max_acq_count) == OK && max_acq_count == 0x80) {
// very likely to be a ll40ls. This is the
// default max acquisition counter
goto ok;
}
if (read_reg(LL40LS_WHO_AM_I_REG, who_am_i) == OK && who_am_i == LL40LS_WHO_AM_I_REG_VAL) {
// it is responding correctly to a
// WHO_AM_I. This works with older sensors (pre-production)
goto ok;
}
debug("probe failed reg11=0x%02x reg2=0x%02x\n",
(unsigned)who_am_i,
(unsigned)max_acq_count);
}
// not found on any address
return -EIO;
ok:
_retries = 3;
// reset the sensor to ensure it is in a known state with
// correct settings
return reset_sensor();
}
void LidarLiteI2C::set_minimum_distance(float min)
{
_min_distance = min;
}
void LidarLiteI2C::set_maximum_distance(float max)
{
_max_distance = max;
}
float LidarLiteI2C::get_minimum_distance()
{
return _min_distance;
}
float LidarLiteI2C::get_maximum_distance()
{
return _max_distance;
}
int LidarLiteI2C::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:
reset_sensor();
return OK;
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 LidarLiteI2C::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 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 = transfer(cmd, sizeof(cmd), nullptr, 0);
if (OK != ret) {
perf_count(_comms_errors);
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()
{
const uint8_t cmd[2] = { LL40LS_MEASURE_REG, LL40LS_MSRREG_RESET };
int ret = transfer(cmd, sizeof(cmd), nullptr, 0);
return ret;
}
/*
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 = 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;
ret = transfer(&distance_reg, 1, &val[0], sizeof(val));
if (ret < 0) {
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.
*/
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 = (val[0] << 8) | val[1];
float si_units = distance * 0.01f; /* cm to m */
struct range_finder_report report;
if (distance == 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;
/* 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();
if (si_units > get_minimum_distance() && si_units < get_maximum_distance()) {
report.valid = 1;
}
else {
report.valid = 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 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);
/* 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 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()) {
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 (_measure_ticks > 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,
_measure_ticks - USEC2TICK(LL40LS_CONVERSION_INTERVAL));
return;
}
}
}
if (_collect_phase == false) {
/* measurement phase */
if (OK != measure()) {
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(_buffer_overflows);
perf_print_counter(_sensor_resets);
perf_print_counter(_sensor_zero_resets);
printf("poll interval: %u ticks\n", _measure_ticks);
_reports->print_info("report queue");
printf("distance: %ucm (0x%04x)\n",
(unsigned)_last_distance, (unsigned)_last_distance);
}
src/drivers/ll40ls/LidarLiteI2C.h
+142
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@@ -0,0 +1,142 @@
#pragma once
//Forward declaration
class RingBuffer;
#include <nuttx/wqueue.h>
#include <nuttx/clock.h>
#include <systemlib/perf_counter.h>
#include <drivers/device/i2c.h>
#include <drivers/drv_range_finder.h>
#include <uORB/uORB.h>
#include <uORB/topics/subsystem_info.h>
/* Configuration Constants */
#define LL40LS_BUS PX4_I2C_BUS_EXPANSION
#define LL40LS_BASEADDR 0x62 /* 7-bit address */
#define LL40LS_BASEADDR_OLD 0x42 /* previous 7-bit address */
#define LL40LS_DEVICE_PATH_INT "/dev/ll40ls_int"
#define LL40LS_DEVICE_PATH_EXT "/dev/ll40ls_ext"
/* 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_MAX_ACQ_COUNT_REG 0x02 /* maximum acquisition count register */
#define LL40LS_DISTHIGH_REG 0x8F /* High byte of distance register, auto increment */
#define LL40LS_WHO_AM_I_REG 0x11
#define LL40LS_WHO_AM_I_REG_VAL 0xCA
#define LL40LS_SIGNAL_STRENGTH_REG 0x5b
/* Device limits */
#define LL40LS_MIN_DISTANCE (0.00f)
#define LL40LS_MAX_DISTANCE (60.00f)
// 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 LidarLiteI2C : public device::I2C
{
public:
LidarLiteI2C(int bus, const char *path, int address = LL40LS_BASEADDR);
virtual ~LidarLiteI2C();
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();
/**
* print registers to console
*/
void print_registers();
protected:
virtual int probe();
virtual int read_reg(uint8_t reg, uint8_t &val);
private:
float _min_distance;
float _max_distance;
work_s _work;
RingBuffer *_reports;
bool _sensor_ok;
unsigned _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;
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;
/**< the bus the device is connected to */
int _bus;
/**
* 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();
int reset_sensor();
/**
* 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);
};
src/drivers/ll40ls/ll40ls.cpp
+16 -789
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@@ -34,800 +34,28 @@
/**
* @file ll40ls.cpp
* @author Allyson Kreft
* @author Johan Jansen <jnsn.johan@gmail.com>
*
* Driver for the PulsedLight Lidar-Lite range finders connected via I2C.
* Interface for the PulsedLight Lidar-Lite range finders.
*/
#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 "LidarLiteI2C.h"
#include <board_config.h>
/* Configuration Constants */
#define LL40LS_BUS PX4_I2C_BUS_EXPANSION
#define LL40LS_BASEADDR 0x62 /* 7-bit address */
#define LL40LS_BASEADDR_OLD 0x42 /* previous 7-bit address */
#define LL40LS_DEVICE_PATH_INT "/dev/ll40ls_int"
#define LL40LS_DEVICE_PATH_EXT "/dev/ll40ls_ext"
/* 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_MAX_ACQ_COUNT_REG 0x02 /* maximum acquisition count register */
#define LL40LS_DISTHIGH_REG 0x8F /* High byte of distance register, auto increment */
#define LL40LS_WHO_AM_I_REG 0x11
#define LL40LS_WHO_AM_I_REG_VAL 0xCA
#define LL40LS_SIGNAL_STRENGTH_REG 0x5b
/* Device limits */
#define LL40LS_MIN_DISTANCE (0.00f)
#define LL40LS_MAX_DISTANCE (60.00f)
// 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 */
/* oddly, ERROR is not defined for c++ */
#ifdef ERROR
# undef ERROR
#endif
static const int ERROR = -1;
#include <systemlib/err.h>
#include <fcntl.h>
#include <cstdlib>
#include <string.h>
#include <stdio.h>
#ifndef CONFIG_SCHED_WORKQUEUE
# error This requires CONFIG_SCHED_WORKQUEUE.
#endif
class LL40LS : public device::I2C
{
public:
LL40LS(int bus, const char *path, 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();
/**
* print registers to console
*/
void print_registers();
protected:
virtual int probe();
virtual int read_reg(uint8_t reg, uint8_t &val);
private:
float _min_distance;
float _max_distance;
work_s _work;
RingBuffer *_reports;
bool _sensor_ok;
unsigned _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;
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;
/**< the bus the device is connected to */
int _bus;
/**
* 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();
int reset_sensor();
/**
* 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, const char *path, int address) :
I2C("LL40LS", 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),
_class_instance(-1),
_range_finder_topic(-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")),
_sensor_resets(perf_alloc(PC_COUNT, "ll40ls_resets")),
_sensor_zero_resets(perf_alloc(PC_COUNT, "ll40ls_zero_resets")),
_last_distance(0),
_zero_counter(0),
_pause_measurements(false),
_bus(bus)
{
// up the retries since the device misses the first measure attempts
_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_BASE_DEVICE_PATH, _class_instance);
}
// free perf counters
perf_free(_sample_perf);
perf_free(_comms_errors);
perf_free(_buffer_overflows);
perf_free(_sensor_resets);
perf_free(_sensor_zero_resets);
}
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_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
LL40LS::read_reg(uint8_t reg, uint8_t &val)
{
return transfer(&reg, 1, &val, 1);
}
int
LL40LS::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++) {
uint8_t who_am_i=0, max_acq_count=0;
// set the I2C bus address
set_address(addresses[i]);
/* register 2 defaults to 0x80. If this matches it is
almost certainly a ll40ls */
if (read_reg(LL40LS_MAX_ACQ_COUNT_REG, max_acq_count) == OK && max_acq_count == 0x80) {
// very likely to be a ll40ls. This is the
// default max acquisition counter
goto ok;
}
if (read_reg(LL40LS_WHO_AM_I_REG, who_am_i) == OK && who_am_i == LL40LS_WHO_AM_I_REG_VAL) {
// it is responding correctly to a
// WHO_AM_I. This works with older sensors (pre-production)
goto ok;
}
debug("probe failed reg11=0x%02x reg2=0x%02x\n",
(unsigned)who_am_i,
(unsigned)max_acq_count);
}
// not found on any address
return -EIO;
ok:
_retries = 3;
// reset the sensor to ensure it is in a known state with
// correct settings
return reset_sensor();
}
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:
reset_sensor();
return OK;
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;
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 = transfer(cmd, sizeof(cmd), nullptr, 0);
if (OK != ret) {
perf_count(_comms_errors);
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
LL40LS::reset_sensor()
{
const uint8_t cmd[2] = { LL40LS_MEASURE_REG, LL40LS_MSRREG_RESET };
int ret = transfer(cmd, sizeof(cmd), nullptr, 0);
return ret;
}
/*
dump sensor registers for debugging
*/
void
LL40LS::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 = 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
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) {
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.
*/
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 = (val[0] << 8) | val[1];
float si_units = distance * 0.01f; /* cm to m */
struct range_finder_report report;
if (distance == 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;
/* 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();
if (si_units > get_minimum_distance() && si_units < get_maximum_distance()) {
report.valid = 1;
}
else {
report.valid = 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
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) {
/* try a collection */
if (OK != collect()) {
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 (_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;
}
}
}
if (_collect_phase == false) {
/* measurement phase */
if (OK != measure()) {
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)&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);
perf_print_counter(_sensor_resets);
perf_print_counter(_sensor_zero_resets);
printf("poll interval: %u ticks\n", _measure_ticks);
_reports->print_info("report queue");
printf("distance: %ucm (0x%04x)\n",
(unsigned)_last_distance, (unsigned)_last_distance);
}
/**
* Local functions in support of the shell command.
@@ -841,8 +69,8 @@ namespace ll40ls
#endif
const int ERROR = -1;
LL40LS *g_dev_int;
LL40LS *g_dev_ext;
LidarLiteI2C *g_dev_int;
LidarLiteI2C *g_dev_ext;
void start(int bus);
void stop(int bus);
@@ -855,14 +83,13 @@ void usage();
/**
* Start the driver.
*/
void
start(int bus)
void start(int bus)
{
/* create the driver, attempt expansion bus first */
if (bus == -1 || bus == PX4_I2C_BUS_EXPANSION) {
if (g_dev_ext != nullptr)
errx(0, "already started external");
g_dev_ext = new LL40LS(PX4_I2C_BUS_EXPANSION, LL40LS_DEVICE_PATH_EXT);
g_dev_ext = new LidarLiteI2C(PX4_I2C_BUS_EXPANSION, LL40LS_DEVICE_PATH_EXT);
if (g_dev_ext != nullptr && OK != g_dev_ext->init()) {
delete g_dev_ext;
g_dev_ext = nullptr;
@@ -877,7 +104,7 @@ start(int bus)
if (bus == -1 || bus == PX4_I2C_BUS_ONBOARD) {
if (g_dev_int != nullptr)
errx(0, "already started internal");
g_dev_int = new LL40LS(PX4_I2C_BUS_ONBOARD, LL40LS_DEVICE_PATH_INT);
g_dev_int = new LidarLiteI2C(PX4_I2C_BUS_ONBOARD, LL40LS_DEVICE_PATH_INT);
if (g_dev_int != nullptr && OK != g_dev_int->init()) {
/* tear down the failing onboard instance */
delete g_dev_int;
@@ -938,7 +165,7 @@ fail:
*/
void stop(int bus)
{
LL40LS **g_dev = (bus == PX4_I2C_BUS_ONBOARD?&g_dev_int:&g_dev_ext);
LidarLiteI2C **g_dev = (bus == PX4_I2C_BUS_ONBOARD?&g_dev_int:&g_dev_ext);
if (*g_dev != nullptr) {
delete *g_dev;
*g_dev = nullptr;
@@ -1048,7 +275,7 @@ reset(int bus)
void
info(int bus)
{
LL40LS *g_dev = (bus == PX4_I2C_BUS_ONBOARD?g_dev_int:g_dev_ext);
LidarLiteI2C *g_dev = (bus == PX4_I2C_BUS_ONBOARD?g_dev_int:g_dev_ext);
if (g_dev == nullptr) {
errx(1, "driver not running");
}
@@ -1065,7 +292,7 @@ info(int bus)
void
regdump(int bus)
{
LL40LS *g_dev = (bus == PX4_I2C_BUS_ONBOARD?g_dev_int:g_dev_ext);
LidarLiteI2C *g_dev = (bus == PX4_I2C_BUS_ONBOARD?g_dev_int:g_dev_ext);
if (g_dev == nullptr) {
errx(1, "driver not running");
}
src/drivers/ll40ls/module.mk
+2 -1
View File
@@ -37,6 +37,7 @@
MODULE_COMMAND = ll40ls
SRCS = ll40ls.cpp
SRCS = ll40ls.cpp \
LidarLiteI2C.cpp
MAXOPTIMIZATION = -Os