move pressure altitude from baros to sensors module

msg/sensor_baro.msg

@@ -1,5 +1,4 @@
 float32 pressure	# static pressure measurement in millibar
-float32 altitude	# ISA pressure altitude in meters
 float32 temperature	# static temperature measurement in deg C
 uint64 error_count
 uint32 device_id	# Sensor ID that must be unique for each baro sensor and must not change

msg/sensor_combined.msg

@@ -20,5 +20,6 @@ int32 magnetometer_timestamp_relative	# timestamp + magnetometer_timestamp_relat
 float32[3] magnetometer_ga		# Magnetic field in NED body frame, in Gauss
 
 int32 baro_timestamp_relative		# timestamp + baro_timestamp_relative = Barometer timestamp
-float32 baro_alt_meter			# Altitude, already temp. comp.
+float32 baro_alt_meter			# Altitude above MSL calculated from temperature compensated baro sensor data using an ISA corrected for sea level pressure SENS_BARO_QNH.
 float32 baro_temp_celcius		# Temperature in degrees celsius
+float32 baro_pressure_pa		# Absolute pressure in pascals

src/drivers/barometer/bmp280/bmp280.cpp

@@ -117,9 +117,6 @@ private:
 
 	bool			_collect_phase;
 
-	/* altitude conversion calibration */
-	unsigned		_msl_pressure;	/* in Pa */
-
 	orb_advert_t		_baro_topic;
 	int					_orb_class_instance;
 	int					_class_instance;
@@ -157,7 +154,6 @@ BMP280::BMP280(bmp280::IBMP280 *interface, const char *path) :
 	_report_ticks(0),
 	_reports(nullptr),
 	_collect_phase(false),
-	_msl_pressure(101325),
 	_baro_topic(nullptr),
 	_orb_class_instance(-1),
 	_class_instance(-1),
@@ -418,19 +414,6 @@ BMP280::ioctl(struct file *filp, int cmd, unsigned long arg)
 		 */
 		return OK;
 
-	case BAROIOCSMSLPRESSURE:
-
-		/* range-check for sanity */
-		if ((arg < 80000) || (arg > 120000)) {
-			return -EINVAL;
-		}
-
-		_msl_pressure = arg;
-		return OK;
-
-	case BAROIOCGMSLPRESSURE:
-		return _msl_pressure;
-
 	default:
 		break;
 	}
@@ -551,28 +534,6 @@ BMP280::collect()
 	report.temperature = _T;
 	report.pressure = _P / 100.0f; // to mbar
 
-
-	/* altitude calculations based on http://www.kansasflyer.org/index.asp?nav=Avi&sec=Alti&tab=Theory&pg=1 */
-
-	/* tropospheric properties (0-11km) for standard atmosphere */
-	const float T1 = 15.0f + 273.15f;	/* temperature at base height in Kelvin */
-	const float a  = -6.5f / 1000.0f;	/* temperature gradient in degrees per metre */
-	const float g  = 9.80665f;	/* gravity constant in m/s/s */
-	const float R  = 287.05f;	/* ideal gas constant in J/kg/K */
-	float pK = _P / _msl_pressure;
-
-	/*
-	 * Solve:
-	 *
-	 *     /        -(aR / g)     \
-	 *    | (p / p1)          . T1 | - T1
-	 *     \                      /
-	 * h = -------------------------------  + h1
-	 *                   a
-	 */
-	report.altitude = (((powf(pK, (-(a * R) / g))) * T1) - T1) / a;
-
-
 	/* publish it */
 	if (!(_pub_blocked)) {
 		/* publish it */
@@ -595,6 +556,7 @@ BMP280::print_info()
 	perf_print_counter(_sample_perf);
 	perf_print_counter(_comms_errors);
 	printf("poll interval:  %u us \n", _report_ticks * USEC_PER_TICK);
+	_reports->print_info("report queue");
 
 	sensor_baro_s brp = {};
 	_reports->get(&brp);
@@ -640,7 +602,6 @@ void	start(enum BMP280_BUS busid);
 void	test(enum BMP280_BUS busid);
 void	reset(enum BMP280_BUS busid);
 void	info();
-void	calibrate(unsigned altitude, enum BMP280_BUS busid);
 void	usage();
 
 
@@ -868,92 +829,10 @@ info()
 	exit(0);
 }
 
-/**
- * Calculate actual MSL pressure given current altitude
- */
-void
-calibrate(unsigned altitude, enum BMP280_BUS busid)
-{
-	struct bmp280_bus_option &bus = find_bus(busid);
-	struct baro_report report;
-	float	pressure;
-	float	p1;
-
-	int fd;
-
-	fd = open(bus.devpath, O_RDONLY);
-
-	if (fd < 0) {
-		PX4_ERR("open failed (try 'bmp280 start' if the driver is not running)");
-		exit(1);
-	}
-
-	/* start the sensor polling at max */
-	if (OK != ioctl(fd, SENSORIOCSPOLLRATE, SENSOR_POLLRATE_MAX)) {
-		PX4_ERR("failed to set poll rate");
-		exit(1);
-	}
-
-	/* average a few measurements */
-	pressure = 0.0f;
-
-	for (unsigned i = 0; i < 20; i++) {
-		struct pollfd fds;
-		int ret;
-		ssize_t sz;
-
-		/* wait for data to be ready */
-		fds.fd = fd;
-		fds.events = POLLIN;
-		ret = poll(&fds, 1, 1000);
-
-		if (ret != 1) {
-			PX4_ERR("timed out waiting for sensor data");
-			exit(1);
-		}
-
-		/* now go get it */
-		sz = read(fd, &report, sizeof(report));
-
-		if (sz != sizeof(report)) {
-			PX4_ERR("sensor read failed");
-			exit(1);
-		}
-
-		pressure += report.pressure;
-	}
-
-	pressure /= 20;		/* average */
-	pressure /= 10;		/* scale from millibar to kPa */
-
-	/* tropospheric properties (0-11km) for standard atmosphere */
-	const float T1 = 15.0 + 273.15;	/* temperature at base height in Kelvin */
-	const float a  = -6.5 / 1000;	/* temperature gradient in degrees per metre */
-	const float g  = 9.80665f;	/* gravity constant in m/s/s */
-	const float R  = 287.05f;	/* ideal gas constant in J/kg/K */
-
-	PX4_WARN("averaged pressure %10.4fkPa at %um", (double)pressure, altitude);
-
-	p1 = pressure * (powf(((T1 + (a * (float)altitude)) / T1), (g / (a * R))));
-
-	PX4_WARN("calculated MSL pressure %10.4fkPa", (double)p1);
-
-	/* save as integer Pa */
-	p1 *= 1000.0f;
-
-	if (ioctl(fd, BAROIOCSMSLPRESSURE, (unsigned long)p1) != OK) {
-		PX4_ERR("BAROIOCSMSLPRESSURE");
-		exit(1);
-	}
-
-	close(fd);
-	exit(0);
-}
-
 void
 usage()
 {
-	PX4_WARN("missing command: try 'start', 'info', 'test', 'test2', 'reset', 'calibrate'");
+	PX4_WARN("missing command: try 'start', 'info', 'test', 'test2', 'reset'");
 	PX4_WARN("options:");
 	PX4_WARN("    -X    (external I2C bus TODO)");
 	PX4_WARN("    -I    (internal I2C bus TODO)");
@@ -1026,20 +905,6 @@ bmp280_main(int argc, char *argv[])
 		bmp280::info();
 	}
 
-	/*
-	 * Perform MSL pressure calibration given an altitude in metres
-	 */
-	if (!strcmp(verb, "calibrate")) {
-		if (argc < 2) {
-			PX4_ERR("missing altitude");
-			exit(1);
-		}
-
-		long altitude = strtol(argv[optind + 1], nullptr, 10);
-
-		bmp280::calibrate(altitude, busid);
-	}
-
 	PX4_ERR("unrecognized command, try 'start', 'test', 'reset' or 'info'");
 	exit(1);
 }

src/drivers/barometer/lps25h/lps25h.cpp

@@ -217,9 +217,6 @@ private:
 	ringbuffer::RingBuffer	*_reports;
 	bool			_collect_phase;
 
-	/* altitude conversion calibration */
-	unsigned		_msl_pressure;	/* in Pa */
-
 	orb_advert_t		_baro_topic;
 	int			_orb_class_instance;
 	int			_class_instance;
@@ -247,17 +244,6 @@ private:
 	 */
 	int			reset();
 
-	/**
-	 * Perform the on-sensor scale calibration routine.
-	 *
-	 * @note The sensor will continue to provide measurements, these
-	 *	 will however reflect the uncalibrated sensor state until
-	 *	 the calibration routine has been completed.
-	 *
-	 * @param enable set to 1 to enable self-test strap, 0 to disable
-	 */
-	int			calibrate(struct file *filp, unsigned enable);
-
 	/**
 	 * Perform a poll cycle; collect from the previous measurement
 	 * and start a new one.
@@ -329,7 +315,6 @@ LPS25H::LPS25H(device::Device *interface, const char *path) :
 	_measure_ticks(0),
 	_reports(nullptr),
 	_collect_phase(false),
-	_msl_pressure(101325),
 	_baro_topic(nullptr),
 	_orb_class_instance(-1),
 	_class_instance(-1),
@@ -555,19 +540,6 @@ LPS25H::ioctl(struct file *filp, int cmd, unsigned long arg)
 	case SENSORIOCRESET:
 		return reset();
 
-	case BAROIOCSMSLPRESSURE:
-
-		/* range-check for sanity */
-		if ((arg < 80000) || (arg > 120000)) {
-			return -EINVAL;
-		}
-
-		_msl_pressure = arg;
-		return OK;
-
-	case BAROIOCGMSLPRESSURE:
-		return _msl_pressure;
-
 	case DEVIOCGDEVICEID:
 		return _interface->ioctl(cmd, dummy);
 
@@ -729,19 +701,15 @@ LPS25H::collect()
 	}
 
 	/* get measurements from the device */
-	new_report.temperature = 42.5 + (report.t / 480);
+	new_report.temperature = 42.5f + (report.t / 480);
 
 	/* raw pressure */
 	uint32_t raw = report.p_xl + (report.p_l << 8) + (report.p_h << 16);
 
 	/* Pressure and MSL in mBar */
-	double p = raw / 4096.0;
-	double msl = _msl_pressure / 100.0;
-
-	double alt = (1.0 - pow(p / msl, 0.190263)) * 44330.8;
+	float p = raw / 4096.0f;
 
 	new_report.pressure = p;
-	new_report.altitude = alt;
 
 	/* get device ID */
 	new_report.device_id = _device_id.devid;
@@ -836,7 +804,6 @@ struct lps25h_bus_option &find_bus(enum LPS25H_BUS busid);
 void	test(enum LPS25H_BUS busid);
 void	reset(enum LPS25H_BUS busid);
 void	info();
-void	calibrate(unsigned altitude, enum LPS25H_BUS busid);
 void	usage();
 
 /**
@@ -996,27 +963,6 @@ test(enum LPS25H_BUS busid)
 	errx(0, "PASS");
 }
 
-
-/**
- * Calculate actual MSL pressure given current altitude
- */
-void
-calibrate(unsigned altitude, enum LPS25H_BUS busid)
-{
-	struct lps25h_bus_option &bus = find_bus(busid);
-	const char *path = bus.devpath;
-
-	int fd = open(path, O_RDONLY);
-
-	if (fd < 0) {
-		err(1, "%s open failed (try 'lps25h start' if the driver is not running", path);
-	}
-
-	// TODO: Implement calibration
-
-	close(fd);
-}
-
 /**
  * Reset the driver.
  */
@@ -1064,7 +1010,7 @@ info()
 void
 usage()
 {
-	warnx("missing command: try 'start', 'info', 'test', 'reset', 'calibrate'");
+	warnx("missing command: try 'start', 'info', 'test', 'reset'");
 	warnx("options:");
 	warnx("    -X    (external I2C bus)");
 	warnx("    -I    (internal I2C bus)");
@@ -1133,18 +1079,5 @@ lps25h_main(int argc, char *argv[])
 		lps25h::info();
 	}
 
-	/*
-	 * Perform MSL pressure calibration given an altitude in metres
-	 */
-	if (!strcmp(verb, "calibrate")) {
-		if (argc < 2) {
-			errx(1, "missing altitude");
-		}
-
-		long altitude = strtol(argv[optind + 1], nullptr, 10);
-
-		lps25h::calibrate(altitude, busid);
-	}
-
 	errx(1, "unrecognised command, try 'start', 'test', 'reset' or 'info'");
 }

src/drivers/barometer/mpl3115a2/mpl3115a2.cpp

@@ -133,9 +133,6 @@ protected:
 	float			_P;
 	float			_T;
 
-	/* altitude conversion calibration */
-	unsigned		_msl_pressure;	/* in Pa */
-
 	orb_advert_t		_baro_topic;
 	int			_orb_class_instance;
 	int			_class_instance;
@@ -209,7 +206,6 @@ MPL3115A2::MPL3115A2(device::Device *interface, const char *path) :
 	_collect_phase(false),
 	_P(0),
 	_T(0),
-	_msl_pressure(101325),
 	_baro_topic(nullptr),
 	_orb_class_instance(-1),
 	_class_instance(-1),
@@ -492,19 +488,6 @@ MPL3115A2::ioctl(struct file *filp, int cmd, unsigned long arg)
 			return OK;
 		}
 
-	case BAROIOCSMSLPRESSURE:
-
-		/* range-check for sanity */
-		if ((arg < 80000) || (arg > 120000)) {
-			return -EINVAL;
-		}
-
-		_msl_pressure = arg;
-		return OK;
-
-	case BAROIOCGMSLPRESSURE:
-		return _msl_pressure;
-
 	default:
 		break;
 	}
@@ -674,41 +657,6 @@ MPL3115A2::collect()
 
 	/* altitude calculations based on http://www.kansasflyer.org/index.asp?nav=Avi&sec=Alti&tab=Theory&pg=1 */
 
-	/*
-	 * PERFORMANCE HINT:
-	 *
-	 * The single precision calculation is 50 microseconds faster than the double
-	 * precision variant. It is however not obvious if double precision is required.
-	 * Pending more inspection and tests, we'll leave the double precision variant active.
-	 *
-	 * Measurements:
-	 * 	double precision: mpl3115a2_read: 992 events, 258641us elapsed, min 202us max 305us
-	 *	single precision: mpl3115a2_read: 963 events, 208066us elapsed, min 202us max 241us
-	 */
-
-	/* tropospheric properties (0-11km) for standard atmosphere */
-	const double T1 = 15.0 + 273.15;	/* temperature at base height in Kelvin */
-	const double a  = -6.5 / 1000;	/* temperature gradient in degrees per metre */
-	const double g  = 9.80665;	/* gravity constant in m/s/s */
-	const double R  = 287.05;	/* ideal gas constant in J/kg/K */
-
-	/* current pressure at MSL in kPa */
-	double p1 = _msl_pressure / 1000.0;
-
-	/* measured pressure in kPa */
-	double p = (double) _P / 1000.0;
-
-	/*
-	 * Solve:
-	 *
-	 *     /        -(aR / g)     \
-	 *    | (p / p1)          . T1 | - T1
-	 *     \                      /
-	 * h = -------------------------------  + h1
-	 *                   a
-	 */
-	report.altitude = (((pow((p / p1), (-(a * R) / g))) * T1) - T1) / a;
-
 	/* publish it */
 	if (!(_pub_blocked) && _baro_topic != nullptr) {
 		/* publish it */
@@ -775,7 +723,6 @@ void	start(enum MPL3115A2_BUS busid);
 void	test(enum MPL3115A2_BUS busid);
 void	reset(enum MPL3115A2_BUS busid);
 void	info();
-void	calibrate(unsigned altitude, enum MPL3115A2_BUS busid);
 void	usage();
 
 /**
@@ -982,87 +929,10 @@ info()
 	exit(0);
 }
 
-/**
- * Calculate actual MSL pressure given current altitude
- */
-void
-calibrate(unsigned altitude, enum MPL3115A2_BUS busid)
-{
-	struct mpl3115a2_bus_option &bus = find_bus(busid);
-	struct baro_report report;
-	float	pressure;
-	float	p1;
-
-	int fd;
-
-	fd = open(bus.devpath, O_RDONLY);
-
-	if (fd < 0) {
-		err(1, "open failed (try 'mpl3115a2 start' if the driver is not running)");
-	}
-
-	/* start the sensor polling at max */
-	if (OK != ioctl(fd, SENSORIOCSPOLLRATE, SENSOR_POLLRATE_MAX)) {
-		errx(1, "failed to set poll rate");
-	}
-
-	/* average a few measurements */
-	pressure = 0.0f;
-
-	for (unsigned i = 0; i < 20; i++) {
-		struct pollfd fds;
-		int ret;
-		ssize_t sz;
-
-		/* wait for data to be ready */
-		fds.fd = fd;
-		fds.events = POLLIN;
-		ret = poll(&fds, 1, 1000);
-
-		if (ret != 1) {
-			errx(1, "timed out waiting for sensor data");
-		}
-
-		/* now go get it */
-		sz = read(fd, &report, sizeof(report));
-
-		if (sz != sizeof(report)) {
-			err(1, "sensor read failed");
-		}
-
-		pressure += report.pressure;
-	}
-
-	pressure /= 20;		/* average */
-	pressure /= 10;		/* scale from millibar to kPa */
-
-	/* tropospheric properties (0-11km) for standard atmosphere */
-	const float T1 = 15.0 + 273.15;	/* temperature at base height in Kelvin */
-	const float a  = -6.5 / 1000;	/* temperature gradient in degrees per metre */
-	const float g  = 9.80665f;	/* gravity constant in m/s/s */
-	const float R  = 287.05f;	/* ideal gas constant in J/kg/K */
-
-	warnx("averaged pressure %10.4fkPa at %um", (double)pressure, altitude);
-
-	p1 = pressure * (powf(((T1 + (a * (float)altitude)) / T1), (g / (a * R))));
-
-	warnx("calculated MSL pressure %10.4fkPa", (double)p1);
-
-	/* save as integer Pa */
-	p1 *= 1000.0f;
-
-	if (ioctl(fd, BAROIOCSMSLPRESSURE, (unsigned long)p1) != OK) {
-		err(1, "BAROIOCSMSLPRESSURE");
-	}
-
-	close(fd);
-	exit(0);
-}
-
 void
 usage()
 {
-	warnx("missing command: try 'start', 'info', 'test', 'reset', 'calibrate'");
+	warnx("missing command: try 'start', 'info', 'test', 'reset'");
 	warnx("options:");
 	warnx("    -X    (external I2C bus)");
 	warnx("    -I    (intternal I2C bus)");
@@ -1126,19 +996,6 @@ mpl3115a2_main(int argc, char *argv[])
 		mpl3115a2::info();
 	}
 
-	/*
-	 * Perform MSL pressure calibration given an altitude in metres
-	 */
-	if (!strcmp(verb, "calibrate")) {
-		if (argc < 2) {
-			errx(1, "missing altitude");
-		}
-
-		long altitude = strtol(argv[myoptind + 1], nullptr, 10);
-
-		mpl3115a2::calibrate(altitude, busid);
-	}
-
 	mpl3115a2::usage();
 	exit(1);
 }

src/drivers/barometer/ms5611/ms5611.cpp

@@ -163,9 +163,6 @@ protected:
 	float			_P;
 	float			_T;
 
-	/* altitude conversion calibration */
-	unsigned		_msl_pressure;	/* in Pa */
-
 	orb_advert_t		_baro_topic;
 	int			_orb_class_instance;
 	int			_class_instance;
@@ -243,7 +240,6 @@ MS5611::MS5611(device::Device *interface, ms5611::prom_u &prom_buf, const char *
 	_TEMP(0),
 	_OFF(0),
 	_SENS(0),
-	_msl_pressure(101325),
 	_baro_topic(nullptr),
 	_orb_class_instance(-1),
 	_class_instance(-1),
@@ -351,8 +347,6 @@ MS5611::init()
 		/* state machine will have generated a report, copy it out */
 		_reports->get(&brp);
 
-		// DEVICE_LOG("altitude (%u) = %.2f", _device_type, (double)brp.altitude);
-
 		if (autodetect) {
 			if (_device_type == MS5611_DEVICE) {
 				if (brp.altitude > 5300.f) {
@@ -571,19 +565,6 @@ MS5611::ioctl(struct file *filp, int cmd, unsigned long arg)
 		 */
 		return OK;
 
-	case BAROIOCSMSLPRESSURE:
-
-		/* range-check for sanity */
-		if ((arg < 80000) || (arg > 120000)) {
-			return -EINVAL;
-		}
-
-		_msl_pressure = arg;
-		return OK;
-
-	case BAROIOCGMSLPRESSURE:
-		return _msl_pressure;
-
 	default:
 		break;
 	}
@@ -827,43 +808,6 @@ MS5611::collect()
 		/* return device ID */
 		report.device_id = _device_id.devid;
 
-		/* altitude calculations based on http://www.kansasflyer.org/index.asp?nav=Avi&sec=Alti&tab=Theory&pg=1 */
-
-		/*
-		 * PERFORMANCE HINT:
-		 *
-		 * The single precision calculation is 50 microseconds faster than the double
-		 * precision variant. It is however not obvious if double precision is required.
-		 * Pending more inspection and tests, we'll leave the double precision variant active.
-		 *
-		 * Measurements:
-		 * 	double precision: ms5611_read: 992 events, 258641us elapsed, min 202us max 305us
-		 *	single precision: ms5611_read: 963 events, 208066us elapsed, min 202us max 241us
-		 */
-
-		/* tropospheric properties (0-11km) for standard atmosphere */
-		const double T1 = 15.0 + 273.15;	/* temperature at base height in Kelvin */
-		const double a  = -6.5 / 1000;	/* temperature gradient in degrees per metre */
-		const double g  = 9.80665;	/* gravity constant in m/s/s */
-		const double R  = 287.05;	/* ideal gas constant in J/kg/K */
-
-		/* current pressure at MSL in kPa */
-		double p1 = _msl_pressure / 1000.0;
-
-		/* measured pressure in kPa */
-		double p = P / 1000.0;
-
-		/*
-		 * Solve:
-		 *
-		 *     /        -(aR / g)     \
-		 *    | (p / p1)          . T1 | - T1
-		 *     \                      /
-		 * h = -------------------------------  + h1
-		 *                   a
-		 */
-		report.altitude = (((pow((p / p1), (-(a * R) / g))) * T1) - T1) / a;
-
 		/* publish it */
 		if (!(_pub_blocked) && _baro_topic != nullptr) {
 			/* publish it */
@@ -892,18 +836,6 @@ MS5611::print_info()
 	printf("poll interval:  %u ticks\n", _measure_ticks);
 	_reports->print_info("report queue");
 	printf("device:         %s\n", _device_type == MS5611_DEVICE ? "ms5611" : "ms5607");
-	printf("TEMP:           %d\n", _TEMP);
-	printf("SENS:           %lld\n", _SENS);
-	printf("OFF:            %lld\n", _OFF);
-
-	printf("factory_setup             %u\n", _prom.factory_setup);
-	printf("c1_pressure_sens          %u\n", _prom.c1_pressure_sens);
-	printf("c2_pressure_offset        %u\n", _prom.c2_pressure_offset);
-	printf("c3_temp_coeff_pres_sens   %u\n", _prom.c3_temp_coeff_pres_sens);
-	printf("c4_temp_coeff_pres_offset %u\n", _prom.c4_temp_coeff_pres_offset);
-	printf("c5_reference_temp         %u\n", _prom.c5_reference_temp);
-	printf("c6_temp_coeff_temp        %u\n", _prom.c6_temp_coeff_temp);
-	printf("serial_and_crc            %u\n", _prom.serial_and_crc);
 
 	sensor_baro_s brp = {};
 	_reports->get(&brp);
@@ -947,7 +879,6 @@ void	start(enum MS5611_BUS busid, enum MS56XX_DEVICE_TYPES device_type);
 void	test(enum MS5611_BUS busid);
 void	reset(enum MS5611_BUS busid);
 void	info();
-void	calibrate(unsigned altitude, enum MS5611_BUS busid);
 void	usage();
 
 /**
@@ -1202,87 +1133,10 @@ info()
 	exit(0);
 }
 
-/**
- * Calculate actual MSL pressure given current altitude
- */
-void
-calibrate(unsigned altitude, enum MS5611_BUS busid)
-{
-	struct ms5611_bus_option &bus = find_bus(busid);
-	struct baro_report report;
-	float	pressure;
-	float	p1;
-
-	int fd;
-
-	fd = open(bus.devpath, O_RDONLY);
-
-	if (fd < 0) {
-		err(1, "open failed (try 'ms5611 start' if the driver is not running)");
-	}
-
-	/* start the sensor polling at max */
-	if (OK != ioctl(fd, SENSORIOCSPOLLRATE, SENSOR_POLLRATE_MAX)) {
-		errx(1, "failed to set poll rate");
-	}
-
-	/* average a few measurements */
-	pressure = 0.0f;
-
-	for (unsigned i = 0; i < 20; i++) {
-		struct pollfd fds;
-		int ret;
-		ssize_t sz;
-
-		/* wait for data to be ready */
-		fds.fd = fd;
-		fds.events = POLLIN;
-		ret = poll(&fds, 1, 1000);
-
-		if (ret != 1) {
-			errx(1, "timed out waiting for sensor data");
-		}
-
-		/* now go get it */
-		sz = read(fd, &report, sizeof(report));
-
-		if (sz != sizeof(report)) {
-			err(1, "sensor read failed");
-		}
-
-		pressure += report.pressure;
-	}
-
-	pressure /= 20;		/* average */
-	pressure /= 10;		/* scale from millibar to kPa */
-
-	/* tropospheric properties (0-11km) for standard atmosphere */
-	const float T1 = 15.0 + 273.15;	/* temperature at base height in Kelvin */
-	const float a  = -6.5 / 1000;	/* temperature gradient in degrees per metre */
-	const float g  = 9.80665f;	/* gravity constant in m/s/s */
-	const float R  = 287.05f;	/* ideal gas constant in J/kg/K */
-
-	warnx("averaged pressure %10.4fkPa at %um", (double)pressure, altitude);
-
-	p1 = pressure * (powf(((T1 + (a * (float)altitude)) / T1), (g / (a * R))));
-
-	warnx("calculated MSL pressure %10.4fkPa", (double)p1);
-
-	/* save as integer Pa */
-	p1 *= 1000.0f;
-
-	if (ioctl(fd, BAROIOCSMSLPRESSURE, (unsigned long)p1) != OK) {
-		err(1, "BAROIOCSMSLPRESSURE");
-	}
-
-	close(fd);
-	exit(0);
-}
-
 void
 usage()
 {
-	warnx("missing command: try 'start', 'info', 'test', 'test2', 'reset', 'calibrate'");
+	warnx("missing command: try 'start', 'info', 'test', 'test2', 'reset'");
 	warnx("options:");
 	warnx("    -X    (external I2C bus)");
 	warnx("    -I    (intternal I2C bus)");
@@ -1378,18 +1232,5 @@ ms5611_main(int argc, char *argv[])
 		ms5611::info();
 	}
 
-	/*
-	 * Perform MSL pressure calibration given an altitude in metres
-	 */
-	if (!strcmp(verb, "calibrate")) {
-		if (argc < 2) {
-			errx(1, "missing altitude");
-		}
-
-		long altitude = strtol(argv[optind + 1], nullptr, 10);
-
-		ms5611::calibrate(altitude, busid);
-	}
-
 	errx(1, "unrecognised command, try 'start', 'test', 'reset' or 'info'");
 }

src/drivers/drv_baro.h

@@ -53,17 +53,4 @@
 #include <uORB/topics/sensor_baro.h>
 #define baro_report sensor_baro_s
 
-/*
- * ioctl() definitions
- */
-
-#define _BAROIOCBASE		(0x2200)
-#define _BAROIOC(_n)		(_PX4_IOC(_BAROIOCBASE, _n))
-
-/** set corrected MSL pressure in pascals */
-#define BAROIOCSMSLPRESSURE	_BAROIOC(0)
-
-/** get current MSL pressure in pascals */
-#define BAROIOCGMSLPRESSURE	_BAROIOC(1)
-
 #endif /* _DRV_BARO_H */

src/drivers/telemetry/frsky_telemetry/frsky_telemetry.c

@@ -59,7 +59,7 @@
 #include <systemlib/err.h>
 #include <termios.h>
 #include <drivers/drv_hrt.h>
-#include <uORB/topics/sensor_baro.h>
+#include <uORB/topics/sensor_combined.h>
 #include <math.h>	// NAN
 
 #include "sPort_data.h"
@@ -319,15 +319,11 @@ static int frsky_telemetry_thread_main(int argc, char *argv[])
 
 		PX4_INFO("sending FrSky SmartPort telemetry");
 
-		struct sensor_baro_s *sensor_baro = malloc(sizeof(struct sensor_baro_s));
-
-		if (sensor_baro == NULL) {
-			err(1, "could not allocate memory");
-		}
+		struct sensor_combined_s sensor_combined = {};
 
 		float filtered_alt = NAN;
 		float last_baro_alt = 0.f;
-		int sensor_sub = orb_subscribe(ORB_ID(sensor_baro));
+		int sensor_sub = orb_subscribe(ORB_ID(sensor_combined));
 
 		uint32_t lastBATV_ms = 0;
 		uint32_t lastCUR_ms = 0;
@@ -372,13 +368,13 @@ static int frsky_telemetry_thread_main(int argc, char *argv[])
 			orb_check(sensor_sub, &sensor_updated);
 
 			if (sensor_updated) {
-				orb_copy(ORB_ID(sensor_baro), sensor_sub, sensor_baro);
+				orb_copy(ORB_ID(sensor_combined), sensor_sub, &sensor_combined);
 
 				if (isnan(filtered_alt)) {
-					filtered_alt = sensor_baro->altitude;
+					filtered_alt = sensor_combined.baro_alt_meter;
 
 				} else {
-					filtered_alt = .05f * sensor_baro->altitude + .95f * filtered_alt;
+					filtered_alt = .05f * sensor_combined.baro_alt_meter + .95f * filtered_alt;
 				}
 			}
 
@@ -546,7 +542,6 @@ static int frsky_telemetry_thread_main(int argc, char *argv[])
 
 		PX4_DEBUG("freeing sPort memory");
 		sPort_deinit();
-		free(sensor_baro);
 
 		/* either no traffic on the port (0=>timeout), or D type packet */
 

src/modules/ekf2/ekf2_main.cpp

@@ -57,7 +57,6 @@
 #include <uORB/topics/estimator_status.h>
 #include <uORB/topics/optical_flow.h>
 #include <uORB/topics/parameter_update.h>
-#include <uORB/topics/sensor_baro.h>
 #include <uORB/topics/sensor_bias.h>
 #include <uORB/topics/sensor_combined.h>
 #include <uORB/topics/sensor_selection.h>
@@ -521,7 +520,6 @@ void Ekf2::run()
 	int vehicle_land_detected_sub = orb_subscribe(ORB_ID(vehicle_land_detected));
 	int status_sub = orb_subscribe(ORB_ID(vehicle_status));
 	int sensor_selection_sub = orb_subscribe(ORB_ID(sensor_selection));
-	int sensor_baro_sub = orb_subscribe(ORB_ID(sensor_baro));
 	int landing_target_pose_sub = orb_subscribe(ORB_ID(landing_target_pose));
 
 	bool imu_bias_reset_request = false;
@@ -554,8 +552,6 @@ void Ekf2::run()
 	vehicle_attitude_s ev_att = {};
 	vehicle_status_s vehicle_status = {};
 	sensor_selection_s sensor_selection = {};
-	sensor_baro_s sensor_baro = {};
-	sensor_baro.pressure = 1013.5f; // initialise pressure to sea level
 	landing_target_pose_s landing_target_pose = {};
 
 	while (!should_exit()) {
@@ -588,7 +584,6 @@ void Ekf2::run()
 
 		bool gps_updated = false;
 		bool airspeed_updated = false;
-		bool baro_updated = false;
 		bool sensor_selection_updated = false;
 		bool optical_flow_updated = false;
 		bool range_finder_updated = false;
@@ -620,12 +615,6 @@ void Ekf2::run()
 			orb_copy(ORB_ID(airspeed), airspeed_sub, &airspeed);
 		}
 
-		orb_check(sensor_baro_sub, &baro_updated);
-
-		if (baro_updated) {
-			orb_copy(ORB_ID(sensor_baro), sensor_baro_sub, &sensor_baro);
-		}
-
 		orb_check(sensor_selection_sub, &sensor_selection_updated);
 
 		// Always update sensor selction first time through if time stamp is non zero
@@ -808,8 +797,8 @@ void Ekf2::run()
 					float balt_data_avg = _balt_data_sum / (float)_balt_sample_count;
 
 					// estimate air density assuming typical 20degC ambient temperature
-					const float pressure_to_density = 100.0f / (CONSTANTS_AIR_GAS_CONST * (20.0f - CONSTANTS_ABSOLUTE_NULL_CELSIUS));
-					const float rho = pressure_to_density * sensor_baro.pressure;
+					const float pressure_to_density = 1.0f / (CONSTANTS_AIR_GAS_CONST * (20.0f - CONSTANTS_ABSOLUTE_NULL_CELSIUS));
+					const float rho = pressure_to_density * sensors.baro_pressure_pa;
 					_ekf.set_air_density(rho);
 
 					// calculate static pressure error = Pmeas - Ptruth
@@ -1454,7 +1443,6 @@ void Ekf2::run()
 	orb_unsubscribe(vehicle_land_detected_sub);
 	orb_unsubscribe(status_sub);
 	orb_unsubscribe(sensor_selection_sub);
-	orb_unsubscribe(sensor_baro_sub);
 	orb_unsubscribe(landing_target_pose_sub);
 
 	for (unsigned i = 0; i < ORB_MULTI_MAX_INSTANCES; i++) {

src/modules/logger/logger.cpp

@@ -680,7 +680,6 @@ void Logger::add_estimator_replay_topics()
 	add_topic("airspeed");
 	add_topic("distance_sensor");
 	add_topic("optical_flow");
-	add_topic("sensor_baro");
 	add_topic("sensor_combined");
 	add_topic("sensor_selection");
 	add_topic("vehicle_gps_position");

src/modules/mavlink/mavlink_receiver.cpp

@@ -1965,7 +1965,6 @@ MavlinkReceiver::handle_message_hil_sensor(mavlink_message_t *msg)
 
 		baro.timestamp = timestamp;
 		baro.pressure = imu.abs_pressure;
-		baro.altitude = imu.pressure_alt;
 		baro.temperature = imu.temperature;
 
 		/* fake device ID */

src/modules/sensors/sensors.cpp

@@ -267,30 +267,6 @@ Sensors::parameters_update()
 	_rc_update.update_rc_functions();
 	_voted_sensors_update.parameters_update();
 
-	/* update barometer qnh setting */
-	DevHandle h_baro;
-	DevMgr::getHandle(BARO0_DEVICE_PATH, h_baro);
-
-#if !defined(__PX4_QURT) && !defined(__PX4_POSIX_RPI) && !defined(__PX4_POSIX_BEBOP) && !defined(__PX4_POSIX_OCPOC)
-
-	// TODO: this needs fixing for QURT and Raspberry Pi
-	if (!h_baro.isValid()) {
-		if (!_hil_enabled) { // in HIL we don't have a baro
-			PX4_ERR("no barometer found on %s (%d)", BARO0_DEVICE_PATH, h_baro.getError());
-			ret = PX4_ERROR;
-		}
-
-	} else {
-		int baroret = h_baro.ioctl(BAROIOCSMSLPRESSURE, (unsigned long)(_parameters.baro_qnh * 100));
-
-		if (baroret) {
-			PX4_ERR("qnh for baro could not be set");
-			ret = PX4_ERROR;
-		}
-	}
-
-#endif
-
 	return ret;
 }
 
@@ -359,16 +335,15 @@ Sensors::diff_pres_poll(struct sensor_combined_s &raw)
 		airspeed.indicated_airspeed_m_s = math::max(0.0f,
 						  calc_indicated_airspeed_corrected((enum AIRSPEED_COMPENSATION_MODEL)_parameters.air_cmodel,
 								  smodel, _parameters.air_tube_length, _parameters.air_tube_diameter_mm,
-								  diff_pres.differential_pressure_filtered_pa, _voted_sensors_update.baro_pressure(),
+								  diff_pres.differential_pressure_filtered_pa, raw.baro_pressure_pa,
 								  air_temperature_celsius));
 
 		airspeed.true_airspeed_m_s = math::max(0.0f,
-						       calc_true_airspeed_from_indicated(airspeed.indicated_airspeed_m_s,
-								       _voted_sensors_update.baro_pressure(), air_temperature_celsius));
+						       calc_true_airspeed_from_indicated(airspeed.indicated_airspeed_m_s, raw.baro_pressure_pa, air_temperature_celsius));
 
 		airspeed.true_airspeed_unfiltered_m_s = math::max(0.0f,
-							calc_true_airspeed(diff_pres.differential_pressure_raw_pa + _voted_sensors_update.baro_pressure(),
-									_voted_sensors_update.baro_pressure(), air_temperature_celsius));
+							calc_true_airspeed(diff_pres.differential_pressure_raw_pa + raw.baro_pressure_pa, raw.baro_pressure_pa,
+									air_temperature_celsius));
 
 		airspeed.air_temperature_celsius = air_temperature_celsius;
 

src/modules/sensors/voted_sensors_update.cpp

@@ -42,17 +42,14 @@
 #include <systemlib/mavlink_log.h>
 
 #include <conversion/rotation.h>
+#include <geo/geo.h>
 
 #define MAG_ROT_VAL_INTERNAL		-1
 #define CAL_ERROR_APPLY_CAL_MSG "FAILED APPLYING %s CAL #%u"
 
-
 using namespace sensors;
 using namespace DriverFramework;
 
-
-const double VotedSensorsUpdate::_msl_pressure = 101.325;
-
 VotedSensorsUpdate::VotedSensorsUpdate(const Parameters &parameters, bool hil_enabled)
 	: _parameters(parameters), _hil_enabled(hil_enabled)
 {
@@ -551,9 +548,9 @@ void VotedSensorsUpdate::accel_poll(struct sensor_combined_s &raw)
 		if (accel_updated && _accel.enabled[uorb_index]) {
 			struct accel_report accel_report;
 
-			orb_copy(ORB_ID(sensor_accel), _accel.subscription[uorb_index], &accel_report);
+			int ret = orb_copy(ORB_ID(sensor_accel), _accel.subscription[uorb_index], &accel_report);
 
-			if (accel_report.timestamp == 0) {
+			if (ret != PX4_OK || accel_report.timestamp == 0) {
 				continue; //ignore invalid data
 			}
 
@@ -629,6 +626,7 @@ void VotedSensorsUpdate::accel_poll(struct sensor_combined_s &raw)
 	// write the best sensor data to the output variables
 	if (best_index >= 0) {
 		raw.accelerometer_integral_dt = _last_sensor_data[best_index].accelerometer_integral_dt;
+		memcpy(&raw.accelerometer_m_s2, &_last_sensor_data[best_index].accelerometer_m_s2, sizeof(raw.accelerometer_m_s2));
 
 		if (best_index != _accel.last_best_vote) {
 			_accel.last_best_vote = (uint8_t)best_index;
@@ -640,10 +638,6 @@ void VotedSensorsUpdate::accel_poll(struct sensor_combined_s &raw)
 			_selection_changed = true;
 			_selection.accel_device_id = _accel_device_id[best_index];
 		}
-
-		for (unsigned axis_index = 0; axis_index < 3; axis_index++) {
-			raw.accelerometer_m_s2[axis_index] = _last_sensor_data[best_index].accelerometer_m_s2[axis_index];
-		}
 	}
 }
 
@@ -659,9 +653,9 @@ void VotedSensorsUpdate::gyro_poll(struct sensor_combined_s &raw)
 		if (gyro_updated && _gyro.enabled[uorb_index]) {
 			struct gyro_report gyro_report;
 
-			orb_copy(ORB_ID(sensor_gyro), _gyro.subscription[uorb_index], &gyro_report);
+			int ret = orb_copy(ORB_ID(sensor_gyro), _gyro.subscription[uorb_index], &gyro_report);
 
-			if (gyro_report.timestamp == 0) {
+			if (ret != PX4_OK || gyro_report.timestamp == 0) {
 				continue; //ignore invalid data
 			}
 
@@ -736,8 +730,9 @@ void VotedSensorsUpdate::gyro_poll(struct sensor_combined_s &raw)
 
 	// write data for the best sensor to output variables
 	if (best_index >= 0) {
-		raw.gyro_integral_dt = _last_sensor_data[best_index].gyro_integral_dt;
 		raw.timestamp = _last_sensor_data[best_index].timestamp;
+		raw.gyro_integral_dt = _last_sensor_data[best_index].gyro_integral_dt;
+		memcpy(&raw.gyro_rad, &_last_sensor_data[best_index].gyro_rad, sizeof(raw.gyro_rad));
 
 		if (_gyro.last_best_vote != best_index) {
 			_gyro.last_best_vote = (uint8_t)best_index;
@@ -749,10 +744,6 @@ void VotedSensorsUpdate::gyro_poll(struct sensor_combined_s &raw)
 			_selection_changed = true;
 			_selection.gyro_device_id = _gyro_device_id[best_index];
 		}
-
-		for (unsigned axis_index = 0; axis_index < 3; axis_index++) {
-			raw.gyro_rad[axis_index] = _last_sensor_data[best_index].gyro_rad[axis_index];
-		}
 	}
 }
 
@@ -765,19 +756,14 @@ void VotedSensorsUpdate::mag_poll(struct sensor_combined_s &raw)
 		if (mag_updated && _mag.enabled[uorb_index]) {
 			struct mag_report mag_report;
 
-			orb_copy(ORB_ID(sensor_mag), _mag.subscription[uorb_index], &mag_report);
+			int ret = orb_copy(ORB_ID(sensor_mag), _mag.subscription[uorb_index], &mag_report);
 
-			if (mag_report.timestamp == 0) {
+			if (ret != PX4_OK || mag_report.timestamp == 0) {
 				continue; //ignore invalid data
 			}
 
 			// First publication with data
 			if (_mag.priority[uorb_index] == 0) {
-
-				// Parameters update to get offsets, scaling & mag rotation loaded (if not already loaded)
-				parameters_update();
-
-				// Set device priority for the voter
 				int32_t priority = 0;
 				orb_priority(_mag.subscription[uorb_index], &priority);
 				_mag.priority[uorb_index] = (uint8_t)priority;
@@ -799,15 +785,13 @@ void VotedSensorsUpdate::mag_poll(struct sensor_combined_s &raw)
 	_mag.voter.get_best(hrt_absolute_time(), &best_index);
 
 	if (best_index >= 0) {
-		raw.magnetometer_ga[0] = _last_sensor_data[best_index].magnetometer_ga[0];
-		raw.magnetometer_ga[1] = _last_sensor_data[best_index].magnetometer_ga[1];
-		raw.magnetometer_ga[2] = _last_sensor_data[best_index].magnetometer_ga[2];
+		memcpy(&raw.magnetometer_ga, &_last_sensor_data[best_index].magnetometer_ga, sizeof(raw.magnetometer_ga));
 		_mag.last_best_vote = (uint8_t)best_index;
-	}
 
-	if (_selection.mag_device_id != _mag_device_id[best_index]) {
-		_selection_changed = true;
-		_selection.mag_device_id = _mag_device_id[best_index];
+		if (_selection.mag_device_id != _mag_device_id[best_index]) {
+			_selection_changed = true;
+			_selection.mag_device_id = _mag_device_id[best_index];
+		}
 	}
 }
 
@@ -824,9 +808,9 @@ void VotedSensorsUpdate::baro_poll(struct sensor_combined_s &raw)
 		if (baro_updated) {
 			struct baro_report baro_report;
 
-			orb_copy(ORB_ID(sensor_baro), _baro.subscription[uorb_index], &baro_report);
+			int ret = orb_copy(ORB_ID(sensor_baro), _baro.subscription[uorb_index], &baro_report);
 
-			if (baro_report.timestamp == 0) {
+			if (ret != PX4_OK || baro_report.timestamp == 0) {
 				continue; //ignore invalid data
 			}
 
@@ -851,14 +835,13 @@ void VotedSensorsUpdate::baro_poll(struct sensor_combined_s &raw)
 			_baro_device_id[uorb_index] = baro_report.device_id;
 
 			got_update = true;
-			matrix::Vector3f vect(baro_report.altitude, 0.f, 0.f);
+			matrix::Vector3f vect(baro_report.pressure, 0.f, 0.f);
 
-			_last_sensor_data[uorb_index].baro_alt_meter = baro_report.altitude;
 			_last_sensor_data[uorb_index].baro_temp_celcius = baro_report.temperature;
-			_last_baro_pressure[uorb_index] = corrected_pressure;
+			_last_sensor_data[uorb_index].baro_pressure_pa = corrected_pressure;
 
 			_last_baro_timestamp[uorb_index] = baro_report.timestamp;
-			_baro.voter.put(uorb_index, baro_report.timestamp, vect.data(), baro_report.error_count, _baro.priority[uorb_index]);
+			_baro.voter.put(uorb_index, baro_report.timestamp, vect.data, baro_report.error_count, _baro.priority[uorb_index]);
 		}
 	}
 
@@ -868,7 +851,7 @@ void VotedSensorsUpdate::baro_poll(struct sensor_combined_s &raw)
 
 		if (best_index >= 0) {
 			raw.baro_temp_celcius = _last_sensor_data[best_index].baro_temp_celcius;
-			_last_best_baro_pressure = _last_baro_pressure[best_index];
+			raw.baro_pressure_pa = _last_sensor_data[best_index].baro_pressure_pa;
 
 			if (_baro.last_best_vote != best_index) {
 				_baro.last_best_vote = (uint8_t)best_index;
@@ -881,31 +864,16 @@ void VotedSensorsUpdate::baro_poll(struct sensor_combined_s &raw)
 				_selection.baro_device_id = _baro_device_id[best_index];
 			}
 
-			/* altitude calculations based on http://www.kansasflyer.org/index.asp?nav=Avi&sec=Alti&tab=Theory&pg=1 */
-
-			/*
-			 * PERFORMANCE HINT:
-			 *
-			 * The single precision calculation is 50 microseconds faster than the double
-			 * precision variant. It is however not obvious if double precision is required.
-			 * Pending more inspection and tests, we'll leave the double precision variant active.
-			 *
-			 * Measurements:
-			 * 	double precision: ms5611_read: 992 events, 258641us elapsed, min 202us max 305us
-			 *	single precision: ms5611_read: 963 events, 208066us elapsed, min 202us max 241us
-			 */
+			// calculate altitude using the hypsometric equation
 
-			/* tropospheric properties (0-11km) for standard atmosphere */
-			const double T1 = 15.0 + 273.15;	/* temperature at base height in Kelvin */
-			const double a  = -6.5 / 1000;	/* temperature gradient in degrees per metre */
-			const double g  = 9.80665;	/* gravity constant in m/s/s */
-			const double R  = 287.05;	/* ideal gas constant in J/kg/K */
+			static constexpr float T1 = 15.0f - CONSTANTS_ABSOLUTE_NULL_CELSIUS;	/* temperature at base height in Kelvin */
+			static constexpr float a  = -6.5f / 1000.0f;	/* temperature gradient in degrees per metre */
 
-			/* current pressure at MSL in kPa */
-			const double p1 = _msl_pressure;
+			/* current pressure at MSL in kPa (QNH in hPa)*/
+			const float p1 = _parameters.baro_qnh * 0.1f;
 
 			/* measured pressure in kPa */
-			const double p = 0.001f * _last_best_baro_pressure;
+			const float p = raw.baro_pressure_pa * 0.001f;
 
 			/*
 			 * Solve:
@@ -916,7 +884,7 @@ void VotedSensorsUpdate::baro_poll(struct sensor_combined_s &raw)
 			 * h = -------------------------------  + h1
 			 *                   a
 			 */
-			raw.baro_alt_meter = (((pow((p / p1), (-(a * R) / g))) * T1) - T1) / a;
+			raw.baro_alt_meter = (((powf((p / p1), (-(a * CONSTANTS_AIR_GAS_CONST) / CONSTANTS_ONE_G))) * T1) - T1) / a;
 
 		}
 	}

src/modules/sensors/voted_sensors_update.h

@@ -97,9 +97,6 @@ public:
 
 	void print_status();
 
-	/** get the latest baro pressure */
-	float baro_pressure() const { return _last_best_baro_pressure; }
-
 	/**
 	 * call this whenever parameters got updated. Make sure to have initialize_sensors() called at least
 	 * once before calling this.
@@ -246,9 +243,8 @@ private:
 
 	orb_advert_t	_mavlink_log_pub = nullptr;
 
-	float _last_baro_pressure[BARO_COUNT_MAX]; /**< pressure from last baro sensors */
-	float _last_best_baro_pressure = 0.0f; /**< pressure from last best baro */
 	sensor_combined_s _last_sensor_data[SENSOR_COUNT_MAX]; /**< latest sensor data from all sensors instances */
+
 	uint64_t _last_accel_timestamp[ACCEL_COUNT_MAX]; /**< latest full timestamp */
 	uint64_t _last_mag_timestamp[MAG_COUNT_MAX]; /**< latest full timestamp */
 	uint64_t _last_baro_timestamp[BARO_COUNT_MAX]; /**< latest full timestamp */
@@ -273,12 +269,12 @@ private:
 	struct sensor_selection_s _selection = {}; /**< struct containing the sensor selection to be published to the uORB*/
 	orb_advert_t _sensor_selection_pub = nullptr; /**< handle to the sensor selection uORB topic */
 	bool _selection_changed = false; /**< true when a sensor selection has changed and not been published */
+
 	uint32_t _accel_device_id[SENSOR_COUNT_MAX] = {}; /**< accel driver device id for each uorb instance */
 	uint32_t _baro_device_id[SENSOR_COUNT_MAX] = {};
 	uint32_t _gyro_device_id[SENSOR_COUNT_MAX] = {};
 	uint32_t _mag_device_id[SENSOR_COUNT_MAX] = {};
 
-	static const double	_msl_pressure;	/** average sea-level pressure in kPa */
 };
 
 

src/modules/simulator/simulator_mavlink.cpp

@@ -1073,7 +1073,6 @@ int Simulator::publish_sensor_topics(mavlink_hil_sensor_t *imu)
 
 		baro.timestamp = timestamp;
 		baro.pressure = imu->abs_pressure;
-		baro.altitude = imu->pressure_alt;
 		baro.temperature = imu->temperature;
 
 		int baro_multi;

src/modules/uavcan/sensors/baro.cpp

@@ -98,21 +98,6 @@ ssize_t UavcanBarometerBridge::read(struct file *filp, char *buffer, size_t bufl
 int UavcanBarometerBridge::ioctl(struct file *filp, int cmd, unsigned long arg)
 {
 	switch (cmd) {
-	case BAROIOCSMSLPRESSURE: {
-			if ((arg < 80000) || (arg > 120000)) {
-				return -EINVAL;
-
-			} else {
-				DEVICE_LOG("new msl pressure %u", _msl_pressure);
-				_msl_pressure = arg;
-				return OK;
-			}
-		}
-
-	case BAROIOCGMSLPRESSURE: {
-			return _msl_pressure;
-		}
-
 	case SENSORIOCSPOLLRATE: {
 			// not supported yet, pretend that everything is ok
 			return OK;
@@ -168,20 +153,6 @@ void UavcanBarometerBridge::air_pressure_sub_cb(const
 	/* TODO get device ID for sensor */
 	report.device_id = 0;
 
-	/*
-	 * Altitude computation
-	 * Refer to the MS5611 driver for details
-	 */
-	const double T1 = 15.0 + 273.15; // temperature at base height in Kelvin
-	const double a  = -6.5 / 1000;   // temperature gradient in degrees per metre
-	const double g  = 9.80665;       // gravity constant in m/s/s
-	const double R  = 287.05;        // ideal gas constant in J/kg/K
-
-	const double p1 = _msl_pressure / 1000.0;      // current pressure at MSL in kPa
-	const double p = double(msg.static_pressure) / 1000.0; // measured pressure in kPa
-
-	report.altitude = (((std::pow((p / p1), (-(a * R) / g))) * T1) - T1) / a;
-
 	// add to the ring buffer
 	_reports.force(&report);
 

src/modules/uavcan/sensors/baro.hpp

@@ -79,7 +79,6 @@ private:
 
 	ringbuffer::RingBuffer _reports;
 
-	unsigned _msl_pressure = 101325;
 	float last_temperature_kelvin = 0.0f;
 
 };

src/platforms/posix/drivers/barosim/baro.cpp

@@ -101,9 +101,6 @@ protected:
 	/* last report */
 	struct baro_report	report;
 
-	/* altitude conversion calibration */
-	unsigned		_msl_pressure;	/* in Pa */
-
 	orb_advert_t		_baro_topic;
 	int			_orb_class_instance;
 
@@ -136,7 +133,6 @@ BAROSIM::BAROSIM(const char *path) :
 	VirtDevObj("BAROSIM", path, BARO_BASE_DEVICE_PATH, BAROSIM_MEASURE_INTERVAL_US),
 	_reports(nullptr),
 	report{},
-	_msl_pressure(101325),
 	_baro_topic(nullptr),
 	_orb_class_instance(-1),
 	_sample_perf(perf_alloc(PC_ELAPSED, "barosim_read")),
@@ -202,27 +198,6 @@ out:
 int
 BAROSIM::devIOCTL(unsigned long cmd, unsigned long arg)
 {
-	//PX4_WARN("baro IOCTL %" PRIu64 , hrt_absolute_time());
-
-	switch (cmd) {
-
-	case BAROIOCSMSLPRESSURE:
-
-		/* range-check for sanity */
-		if ((arg < 80000) || (arg > 120000)) {
-			return -EINVAL;
-		}
-
-		_msl_pressure = arg;
-		return OK;
-
-	case BAROIOCGMSLPRESSURE:
-		return _msl_pressure;
-
-	default:
-		break;
-	}
-
 	/* give it to the bus-specific superclass */
 	// return bus_ioctl(filp, cmd, arg);
 	return VirtDevObj::devIOCTL(cmd, arg);
@@ -264,7 +239,6 @@ BAROSIM::collect()
 	}
 
 	report.pressure = raw_baro.pressure;
-	report.altitude = raw_baro.altitude;
 	report.temperature = raw_baro.temperature;
 
 	/* fake device ID */

src/platforms/posix/drivers/df_bmp280_wrapper/df_bmp280_wrapper.cpp

@@ -150,40 +150,12 @@ int DfBmp280Wrapper::_publish(struct baro_sensor_data &data)
 {
 	perf_begin(_baro_sample_perf);
 
-	baro_report baro_report = {};
+	baro_report baro_report;
 	baro_report.timestamp = hrt_absolute_time();
 
 	baro_report.pressure = data.pressure_pa / 100.0f; // to mbar
 	baro_report.temperature = data.temperature_c;
 
-	// TODO: verify this, it's just copied from the MS5611 driver.
-
-	// Constant for now
-	const double MSL_PRESSURE_KPA = 101325.0 / 1000.0;
-
-	/* tropospheric properties (0-11km) for standard atmosphere */
-	const double T1 = 15.0 + 273.15;	/* temperature at base height in Kelvin */
-	const double a  = -6.5 / 1000;	/* temperature gradient in degrees per metre */
-	const double g  = 9.80665;	/* gravity constant in m/s/s */
-	const double R  = 287.05;	/* ideal gas constant in J/kg/K */
-
-	/* current pressure at MSL in kPa */
-	double p1 = MSL_PRESSURE_KPA;
-
-	/* measured pressure in kPa */
-	double p = static_cast<double>(data.pressure_pa) / 1000.0;
-
-	/*
-	 * Solve:
-	 *
-	 *     /        -(aR / g)     \
-	 *    | (p / p1)          . T1 | - T1
-	 *     \                      /
-	 * h = -------------------------------  + h1
-	 *                   a
-	 */
-	baro_report.altitude = (((pow((p / p1), (-(a * R) / g))) * T1) - T1) / a;
-
 	// TODO: when is this ever blocked?
 	if (!(m_pub_blocked)) {
 

src/platforms/posix/drivers/df_ms5607_wrapper/df_ms5607_wrapper.cpp

@@ -148,40 +148,12 @@ int DfMS5607Wrapper::_publish(struct baro_sensor_data &data)
 {
 	perf_begin(_baro_sample_perf);
 
-	baro_report baro_report = {};
+	baro_report baro_report;
 	baro_report.timestamp = hrt_absolute_time();
 
 	baro_report.pressure = data.pressure_pa;
 	baro_report.temperature = data.temperature_c;
 
-	// TODO: verify this, it's just copied from the MS5611 driver.
-
-	// Constant for now
-	const double MSL_PRESSURE_KPA = 101325.0 / 1000.0;
-
-	/* tropospheric properties (0-11km) for standard atmosphere */
-	const double T1 = 15.0 + 273.15;	/* temperature at base height in Kelvin */
-	const double a  = -6.5 / 1000;	/* temperature gradient in degrees per metre */
-	const double g  = 9.80665;	/* gravity constant in m/s/s */
-	const double R  = 287.05;	/* ideal gas constant in J/kg/K */
-
-	/* current pressure at MSL in kPa */
-	double p1 = MSL_PRESSURE_KPA;
-
-	/* measured pressure in kPa */
-	double p = static_cast<double>(data.pressure_pa) / 1000.0;
-
-	/*
-	 * Solve:
-	 *
-	 *     /        -(aR / g)     \
-	 *    | (p / p1)          . T1 | - T1
-	 *     \                      /
-	 * h = -------------------------------  + h1
-	 *                   a
-	 */
-	baro_report.altitude = (((pow((p / p1), (-(a * R) / g))) * T1) - T1) / a;
-
 	// TODO: when is this ever blocked?
 	if (!(m_pub_blocked)) {
 

src/platforms/posix/drivers/df_ms5611_wrapper/df_ms5611_wrapper.cpp

@@ -148,40 +148,12 @@ int DfMS5611Wrapper::_publish(struct baro_sensor_data &data)
 {
 	perf_begin(_baro_sample_perf);
 
-	baro_report baro_report = {};
+	baro_report baro_report;
 	baro_report.timestamp = hrt_absolute_time();
 
 	baro_report.pressure = data.pressure_pa / 100.0f; // convert to mbar
 	baro_report.temperature = data.temperature_c;
 
-	// TODO: verify this, it's just copied from the MS5611 driver.
-
-	// Constant for now
-	const double MSL_PRESSURE_KPA = 101325.0 / 1000.0;
-
-	/* tropospheric properties (0-11km) for standard atmosphere */
-	const double T1 = 15.0 + 273.15;	/* temperature at base height in Kelvin */
-	const double a  = -6.5 / 1000;	/* temperature gradient in degrees per metre */
-	const double g  = 9.80665;	/* gravity constant in m/s/s */
-	const double R  = 287.05;	/* ideal gas constant in J/kg/K */
-
-	/* current pressure at MSL in kPa */
-	double p1 = MSL_PRESSURE_KPA;
-
-	/* measured pressure in kPa */
-	double p = static_cast<double>(data.pressure_pa) / 1000.0;
-
-	/*
-	 * Solve:
-	 *
-	 *     /        -(aR / g)     \
-	 *    | (p / p1)          . T1 | - T1
-	 *     \                      /
-	 * h = -------------------------------  + h1
-	 *                   a
-	 */
-	baro_report.altitude = (((pow((p / p1), (-(a * R) / g))) * T1) - T1) / a;
-
 	// TODO: when is this ever blocked?
 	if (!(m_pub_blocked)) {
 

src/systemcmds/tests/test_sensors.c

@@ -251,8 +251,7 @@ baro(int argc, char *argv[], const char *path)
 		return ERROR;
 
 	} else {
-		printf("\tBARO pressure: %8.4f mbar\talt: %8.4f m\ttemp: %8.4f deg C\n", (double)buf.pressure, (double)buf.altitude,
-		       (double)buf.temperature);
+		printf("\tBARO pressure: %8.4f mbar\t temp: %8.4f deg C\n", (double)buf.pressure, (double)buf.temperature);
 	}
 
 	/* Let user know everything is ok */