path: root/src/drivers/px4fmu/fmu.cpp

/****************************************************************************
 *
 *   Copyright (C) 2012-2013 PX4 Development Team. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name PX4 nor the names of its contributors may be
 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 ****************************************************************************/

/**
 * @file fmu.cpp
 *
 * Driver/configurator for the PX4 FMU multi-purpose port on v1 and v2 boards.
 */

#include <nuttx/config.h>

#include <sys/types.h>
#include <stdint.h>
#include <stdbool.h>
#include <stdlib.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 <drivers/device/device.h>
#include <drivers/drv_pwm_output.h>
#include <drivers/drv_gpio.h>
#include <drivers/drv_hrt.h>

#include <board_config.h>

#include <systemlib/systemlib.h>
#include <systemlib/err.h>
#include <systemlib/mixer/mixer.h>
#include <systemlib/pwm_limit/pwm_limit.h>
#include <systemlib/board_serial.h>
#include <drivers/drv_mixer.h>
#include <drivers/drv_rc_input.h>

#include <uORB/topics/actuator_controls.h>
#include <uORB/topics/actuator_outputs.h>
#include <uORB/topics/actuator_armed.h>


#ifdef HRT_PPM_CHANNEL
# include <systemlib/ppm_decode.h>
#endif

/*
 * This is the analog to FMU_INPUT_DROP_LIMIT_US on the IO side
 */

#define CONTROL_INPUT_DROP_LIMIT_MS		20

class PX4FMU : public device::CDev
{
public:
	enum Mode {
		MODE_NONE,
		MODE_2PWM,
		MODE_4PWM,
		MODE_6PWM,
		MODE_8PWM,
	};
	PX4FMU();
	virtual ~PX4FMU();

	virtual int	ioctl(file *filp, int cmd, unsigned long arg);
	virtual ssize_t	write(file *filp, const char *buffer, size_t len);

	virtual int	init();

	int		set_mode(Mode mode);

	int		set_pwm_alt_rate(unsigned rate);
	int		set_pwm_alt_channels(uint32_t channels);

private:
#if defined(CONFIG_ARCH_BOARD_PX4FMU_V1)
	static const unsigned _max_actuators = 4;
#endif
#if defined(CONFIG_ARCH_BOARD_PX4FMU_V2)
	static const unsigned _max_actuators = 6;
#endif
#if defined(CONFIG_ARCH_BOARD_AEROCORE)
	static const unsigned _max_actuators = 8;
#endif

	Mode		_mode;
	unsigned	_pwm_default_rate;
	unsigned	_pwm_alt_rate;
	uint32_t	_pwm_alt_rate_channels;
	unsigned	_current_update_rate;
	int		_task;
	int		_armed_sub;
	orb_advert_t	_outputs_pub;
	actuator_armed_s	_armed;
	unsigned	_num_outputs;
	bool		_primary_pwm_device;

	volatile bool	_task_should_exit;
	bool		_servo_armed;
	bool		_pwm_on;

	MixerGroup	*_mixers;

	uint32_t	_groups_required;
	uint32_t	_groups_subscribed;
	int		_control_subs[NUM_ACTUATOR_CONTROL_GROUPS];
	actuator_controls_s _controls[NUM_ACTUATOR_CONTROL_GROUPS];
	orb_id_t	_control_topics[NUM_ACTUATOR_CONTROL_GROUPS];
	pollfd	_poll_fds[NUM_ACTUATOR_CONTROL_GROUPS];
	unsigned	_poll_fds_num;

	pwm_limit_t	_pwm_limit;
	uint16_t	_failsafe_pwm[_max_actuators];
	uint16_t	_disarmed_pwm[_max_actuators];
	uint16_t	_min_pwm[_max_actuators];
	uint16_t	_max_pwm[_max_actuators];
	unsigned	_num_failsafe_set;
	unsigned	_num_disarmed_set;

	static void	task_main_trampoline(int argc, char *argv[]);
	void		task_main();

	static int	control_callback(uintptr_t handle,
					 uint8_t control_group,
					 uint8_t control_index,
					 float &input);
	void	subscribe();
	int		set_pwm_rate(unsigned rate_map, unsigned default_rate, unsigned alt_rate);
	int		pwm_ioctl(file *filp, int cmd, unsigned long arg);

	struct GPIOConfig {
		uint32_t	input;
		uint32_t	output;
		uint32_t	alt;
	};

	static const GPIOConfig	_gpio_tab[];
	static const unsigned	_ngpio;

	void		gpio_reset(void);
	void		sensor_reset(int ms);
	void		gpio_set_function(uint32_t gpios, int function);
	void		gpio_write(uint32_t gpios, int function);
	uint32_t	gpio_read(void);
	int		gpio_ioctl(file *filp, int cmd, unsigned long arg);

};

const PX4FMU::GPIOConfig PX4FMU::_gpio_tab[] = {
#if defined(CONFIG_ARCH_BOARD_PX4FMU_V1)
	{GPIO_GPIO0_INPUT, GPIO_GPIO0_OUTPUT, 0},
	{GPIO_GPIO1_INPUT, GPIO_GPIO1_OUTPUT, 0},
	{GPIO_GPIO2_INPUT, GPIO_GPIO2_OUTPUT, GPIO_USART2_CTS_1},
	{GPIO_GPIO3_INPUT, GPIO_GPIO3_OUTPUT, GPIO_USART2_RTS_1},
	{GPIO_GPIO4_INPUT, GPIO_GPIO4_OUTPUT, GPIO_USART2_TX_1},
	{GPIO_GPIO5_INPUT, GPIO_GPIO5_OUTPUT, GPIO_USART2_RX_1},
	{GPIO_GPIO6_INPUT, GPIO_GPIO6_OUTPUT, GPIO_CAN2_TX_2},
	{GPIO_GPIO7_INPUT, GPIO_GPIO7_OUTPUT, GPIO_CAN2_RX_2},
#endif
#if defined(CONFIG_ARCH_BOARD_PX4FMU_V2)
	{GPIO_GPIO0_INPUT,       GPIO_GPIO0_OUTPUT,       0},
	{GPIO_GPIO1_INPUT,       GPIO_GPIO1_OUTPUT,       0},
	{GPIO_GPIO2_INPUT,       GPIO_GPIO2_OUTPUT,       0},
	{GPIO_GPIO3_INPUT,       GPIO_GPIO3_OUTPUT,       0},
	{GPIO_GPIO4_INPUT,       GPIO_GPIO4_OUTPUT,       0},
	{GPIO_GPIO5_INPUT,       GPIO_GPIO5_OUTPUT,       0},

	{0,                      GPIO_VDD_5V_PERIPH_EN,   0},
	{0,                      GPIO_VDD_3V3_SENSORS_EN, 0},
	{GPIO_VDD_BRICK_VALID,   0,                       0},
	{GPIO_VDD_SERVO_VALID,   0,                       0},
	{GPIO_VDD_5V_HIPOWER_OC, 0,                       0},
	{GPIO_VDD_5V_PERIPH_OC,  0,                       0},
#endif
#if defined(CONFIG_ARCH_BOARD_AEROCORE)
	/* AeroCore breaks out User GPIOs on J11 */
	{GPIO_GPIO0_INPUT,       GPIO_GPIO0_OUTPUT,       0},
	{GPIO_GPIO1_INPUT,       GPIO_GPIO1_OUTPUT,       0},
	{GPIO_GPIO3_INPUT,       GPIO_GPIO3_OUTPUT,       0},
	{GPIO_GPIO4_INPUT,       GPIO_GPIO4_OUTPUT,       0},
	{GPIO_GPIO5_INPUT,       GPIO_GPIO5_OUTPUT,       0},
	{GPIO_GPIO6_INPUT,       GPIO_GPIO6_OUTPUT,       0},
	{GPIO_GPIO7_INPUT,       GPIO_GPIO7_OUTPUT,       0},
	{GPIO_GPIO8_INPUT,       GPIO_GPIO8_OUTPUT,       0},
	{GPIO_GPIO9_INPUT,       GPIO_GPIO9_OUTPUT,       0},
	{GPIO_GPIO10_INPUT,      GPIO_GPIO10_OUTPUT,      0},
	{GPIO_GPIO11_INPUT,      GPIO_GPIO11_OUTPUT,      0},
#endif
};

const unsigned PX4FMU::_ngpio = sizeof(PX4FMU::_gpio_tab) / sizeof(PX4FMU::_gpio_tab[0]);

namespace
{

PX4FMU	*g_fmu;

} // namespace

PX4FMU::PX4FMU() :
	CDev("fmuservo", PX4FMU_DEVICE_PATH),
	_mode(MODE_NONE),
	_pwm_default_rate(50),
	_pwm_alt_rate(50),
	_pwm_alt_rate_channels(0),
	_current_update_rate(0),
	_task(-1),
	_armed_sub(-1),
	_outputs_pub(-1),
	_num_outputs(0),
	_primary_pwm_device(false),
	_task_should_exit(false),
	_servo_armed(false),
	_pwm_on(false),
	_mixers(nullptr),
	_groups_required(0),
	_groups_subscribed(0),
	_control_subs{-1},
	_poll_fds_num(0),
	_failsafe_pwm{0},
	_disarmed_pwm{0},
	_num_failsafe_set(0),
	_num_disarmed_set(0)
{
	for (unsigned i = 0; i < _max_actuators; i++) {
		_min_pwm[i] = PWM_DEFAULT_MIN;
		_max_pwm[i] = PWM_DEFAULT_MAX;
	}

	_control_topics[0] = ORB_ID(actuator_controls_0);
	_control_topics[1] = ORB_ID(actuator_controls_1);
	_control_topics[2] = ORB_ID(actuator_controls_2);
	_control_topics[3] = ORB_ID(actuator_controls_3);

	memset(_controls, 0, sizeof(_controls));
	memset(_poll_fds, 0, sizeof(_poll_fds));

	_debug_enabled = true;
}

PX4FMU::~PX4FMU()
{
	if (_task != -1) {
		/* tell the task we want it to go away */
		_task_should_exit = true;

		unsigned i = 10;

		do {
			/* wait 50ms - it should wake every 100ms or so worst-case */
			usleep(50000);

			/* if we have given up, kill it */
			if (--i == 0) {
				task_delete(_task);
				break;
			}

		} while (_task != -1);
	}

	/* clean up the alternate device node */
	if (_primary_pwm_device)
		unregister_driver(PWM_OUTPUT_DEVICE_PATH);

	g_fmu = nullptr;
}

int
PX4FMU::init()
{
	int ret;

	ASSERT(_task == -1);

	/* do regular cdev init */
	ret = CDev::init();

	if (ret != OK)
		return ret;

	/* try to claim the generic PWM output device node as well - it's OK if we fail at this */
	ret = register_driver(PWM_OUTPUT_DEVICE_PATH, &fops, 0666, (void *)this);

	if (ret == OK) {
		log("default PWM output device");
		_primary_pwm_device = true;
	}

	/* reset GPIOs */
	gpio_reset();

	/* start the IO interface task */
	_task = task_spawn_cmd("fmuservo",
			       SCHED_DEFAULT,
			       SCHED_PRIORITY_DEFAULT,
			       1600,
			       (main_t)&PX4FMU::task_main_trampoline,
			       nullptr);

	if (_task < 0) {
		debug("task start failed: %d", errno);
		return -errno;
	}

	return OK;
}

void
PX4FMU::task_main_trampoline(int argc, char *argv[])
{
	g_fmu->task_main();
}

int
PX4FMU::set_mode(Mode mode)
{
	/*
	 * Configure for PWM output.
	 *
	 * Note that regardless of the configured mode, the task is always
	 * listening and mixing; the mode just selects which of the channels
	 * are presented on the output pins.
	 */
	switch (mode) {
	case MODE_2PWM:	// v1 multi-port with flow control lines as PWM
		debug("MODE_2PWM");

		/* default output rates */
		_pwm_default_rate = 50;
		_pwm_alt_rate = 50;
		_pwm_alt_rate_channels = 0;

		/* XXX magic numbers */
		up_pwm_servo_init(0x3);
		set_pwm_rate(_pwm_alt_rate_channels, _pwm_default_rate, _pwm_alt_rate);

		break;

	case MODE_4PWM: // v1 multi-port as 4 PWM outs
		debug("MODE_4PWM");

		/* default output rates */
		_pwm_default_rate = 50;
		_pwm_alt_rate = 50;
		_pwm_alt_rate_channels = 0;

		/* XXX magic numbers */
		up_pwm_servo_init(0xf);
		set_pwm_rate(_pwm_alt_rate_channels, _pwm_default_rate, _pwm_alt_rate);

		break;

	case MODE_6PWM: // v2 PWMs as 6 PWM outs
		debug("MODE_6PWM");

		/* default output rates */
		_pwm_default_rate = 50;
		_pwm_alt_rate = 50;
		_pwm_alt_rate_channels = 0;

		/* XXX magic numbers */
		up_pwm_servo_init(0x3f);
		set_pwm_rate(_pwm_alt_rate_channels, _pwm_default_rate, _pwm_alt_rate);

		break;

#ifdef CONFIG_ARCH_BOARD_AEROCORE
	case MODE_8PWM: // AeroCore PWMs as 8 PWM outs
		debug("MODE_8PWM");
		/* default output rates */
		_pwm_default_rate = 50;
		_pwm_alt_rate = 50;
		_pwm_alt_rate_channels = 0;

		/* XXX magic numbers */
		up_pwm_servo_init(0xff);
		set_pwm_rate(_pwm_alt_rate_channels, _pwm_default_rate, _pwm_alt_rate);
		break;
#endif

	case MODE_NONE:
		debug("MODE_NONE");

		_pwm_default_rate = 10;	/* artificially reduced output rate */
		_pwm_alt_rate = 10;
		_pwm_alt_rate_channels = 0;

		/* disable servo outputs - no need to set rates */
		up_pwm_servo_deinit();

		break;

	default:
		return -EINVAL;
	}

	_mode = mode;
	return OK;
}

int
PX4FMU::set_pwm_rate(uint32_t rate_map, unsigned default_rate, unsigned alt_rate)
{
	debug("set_pwm_rate %x %u %u", rate_map, default_rate, alt_rate);

	for (unsigned pass = 0; pass < 2; pass++) {
		for (unsigned group = 0; group < _max_actuators; group++) {

			// get the channel mask for this rate group
			uint32_t mask = up_pwm_servo_get_rate_group(group);

			if (mask == 0)
				continue;

			// all channels in the group must be either default or alt-rate
			uint32_t alt = rate_map & mask;

			if (pass == 0) {
				// preflight
				if ((alt != 0) && (alt != mask)) {
					warn("rate group %u mask %x bad overlap %x", group, mask, alt);
					// not a legal map, bail
					return -EINVAL;
				}

			} else {
				// set it - errors here are unexpected
				if (alt != 0) {
					if (up_pwm_servo_set_rate_group_update(group, _pwm_alt_rate) != OK) {
						warn("rate group set alt failed");
						return -EINVAL;
					}

				} else {
					if (up_pwm_servo_set_rate_group_update(group, _pwm_default_rate) != OK) {
						warn("rate group set default failed");
						return -EINVAL;
					}
				}
			}
		}
	}

	_pwm_alt_rate_channels = rate_map;
	_pwm_default_rate = default_rate;
	_pwm_alt_rate = alt_rate;

	return OK;
}

int
PX4FMU::set_pwm_alt_rate(unsigned rate)
{
	return set_pwm_rate(_pwm_alt_rate_channels, _pwm_default_rate, rate);
}

int
PX4FMU::set_pwm_alt_channels(uint32_t channels)
{
	return set_pwm_rate(channels, _pwm_default_rate, _pwm_alt_rate);
}

void
PX4FMU::subscribe()
{
	/* subscribe/unsubscribe to required actuator control groups */
	uint32_t sub_groups = _groups_required & ~_groups_subscribed;
	uint32_t unsub_groups = _groups_subscribed & ~_groups_required;
	_poll_fds_num = 0;
	for (unsigned i = 0; i < NUM_ACTUATOR_CONTROL_GROUPS; i++) {
		if (sub_groups & (1 << i)) {
			warnx("subscribe to actuator_controls_%d", i);
			_control_subs[i] = orb_subscribe(_control_topics[i]);
		}
		if (unsub_groups & (1 << i)) {
			warnx("unsubscribe from actuator_controls_%d", i);
			::close(_control_subs[i]);
			_control_subs[i] = -1;
		}

		if (_control_subs[i] > 0) {
			_poll_fds[_poll_fds_num].fd = _control_subs[i];
			_poll_fds[_poll_fds_num].events = POLLIN;
			_poll_fds_num++;
		}
	}
}

void
PX4FMU::task_main()
{
	/* force a reset of the update rate */
	_current_update_rate = 0;

	_armed_sub = orb_subscribe(ORB_ID(actuator_armed));

	/* advertise the mixed control outputs */
	actuator_outputs_s outputs;
	memset(&outputs, 0, sizeof(outputs));

#ifdef HRT_PPM_CHANNEL
	// rc input, published to ORB
	struct rc_input_values rc_in;
	orb_advert_t to_input_rc = 0;

	memset(&rc_in, 0, sizeof(rc_in));
	rc_in.input_source = RC_INPUT_SOURCE_PX4FMU_PPM;
#endif

	/* initialize PWM limit lib */
	pwm_limit_init(&_pwm_limit);

	log("starting");

	/* loop until killed */
	while (!_task_should_exit) {
		if (_groups_subscribed != _groups_required) {
			subscribe();
			_groups_subscribed = _groups_required;
			/* force setting update rate */
			_current_update_rate = 0;
		}

		/*
		 * Adjust actuator topic update rate to keep up with
		 * the highest servo update rate configured.
		 *
		 * We always mix at max rate; some channels may update slower.
		 */
		unsigned max_rate = (_pwm_default_rate > _pwm_alt_rate) ? _pwm_default_rate : _pwm_alt_rate;

		if (_current_update_rate != max_rate) {
			_current_update_rate = max_rate;
			int update_rate_in_ms = int(1000 / _current_update_rate);

			/* reject faster than 500 Hz updates */
			if (update_rate_in_ms < 2) {
				update_rate_in_ms = 2;
			}

			/* reject slower than 10 Hz updates */
			if (update_rate_in_ms > 100) {
				update_rate_in_ms = 100;
			}

			debug("adjusted actuator update interval to %ums", update_rate_in_ms);
			for (unsigned i = 0; i < NUM_ACTUATOR_CONTROL_GROUPS; i++) {
				if (_control_subs[i] > 0) {
					orb_set_interval(_control_subs[i], update_rate_in_ms);
				}
			}

			// set to current max rate, even if we are actually checking slower/faster
			_current_update_rate = max_rate;
		}

		/* sleep waiting for data, stopping to check for PPM
		 * input at 50Hz */
		int ret = ::poll(_poll_fds, _poll_fds_num, CONTROL_INPUT_DROP_LIMIT_MS);

		/* this would be bad... */
		if (ret < 0) {
			log("poll error %d", errno);
			continue;

		} else if (ret == 0) {
			/* timeout: no control data, switch to failsafe values */
//			warnx("no PWM: failsafe");

		} else {

			/* get controls for required topics */
			unsigned poll_id = 0;
			for (unsigned i = 0; i < NUM_ACTUATOR_CONTROL_GROUPS; i++) {
				if (_control_subs[i] > 0) {
					if (_poll_fds[poll_id].revents & POLLIN) {
						orb_copy(_control_topics[i], _control_subs[i], &_controls[i]);
					}
					poll_id++;
				}
			}

			/* can we mix? */
			if (_mixers != nullptr) {

				unsigned num_outputs;

				switch (_mode) {
				case MODE_2PWM:
					num_outputs = 2;
					break;

				case MODE_4PWM:
					num_outputs = 4;
					break;

				case MODE_6PWM:
					num_outputs = 6;
					break;

				case MODE_8PWM:
					num_outputs = 8;
					break;
				default:
					num_outputs = 0;
					break;
				}

				/* do mixing */
				outputs.noutputs = _mixers->mix(&outputs.output[0], num_outputs);
				outputs.timestamp = hrt_absolute_time();

				/* iterate actuators */
				for (unsigned i = 0; i < num_outputs; i++) {
					/* last resort: catch NaN and INF */
					if ((i >= outputs.noutputs) ||
						!isfinite(outputs.output[i])) {
						/*
						 * Value is NaN, INF or out of band - set to the minimum value.
						 * This will be clearly visible on the servo status and will limit the risk of accidentally
						 * spinning motors. It would be deadly in flight.
						 */
						outputs.output[i] = -1.0f;
					}
				}

				uint16_t pwm_limited[num_outputs];

				/* the PWM limit call takes care of out of band errors and constrains */
				pwm_limit_calc(_servo_armed, num_outputs, _disarmed_pwm, _min_pwm, _max_pwm, outputs.output, pwm_limited, &_pwm_limit);

				/* output to the servos */
				for (unsigned i = 0; i < num_outputs; i++) {
					up_pwm_servo_set(i, pwm_limited[i]);
				}

				/* publish mixed control outputs */
				if (_outputs_pub < 0) {
					_outputs_pub = orb_advertise(_primary_pwm_device ? ORB_ID_VEHICLE_CONTROLS : ORB_ID(actuator_outputs_1), &outputs);
				} else {

					orb_publish(_primary_pwm_device ? ORB_ID_VEHICLE_CONTROLS : ORB_ID(actuator_outputs_1), _outputs_pub, &outputs);
				}
			}
		}

		/* check arming state */
		bool updated = false;
		orb_check(_armed_sub, &updated);

		if (updated) {
			orb_copy(ORB_ID(actuator_armed), _armed_sub, &_armed);

			/* update the armed status and check that we're not locked down */
			bool set_armed = _armed.armed && !_armed.lockdown;

			if (_servo_armed != set_armed)
				_servo_armed = set_armed;

			/* update PWM status if armed or if disarmed PWM values are set */
			bool pwm_on = (_armed.armed || _num_disarmed_set > 0);

			if (_pwm_on != pwm_on) {
				_pwm_on = pwm_on;
				up_pwm_servo_arm(pwm_on);
			}
		}

#ifdef HRT_PPM_CHANNEL

		// see if we have new PPM input data
		if (ppm_last_valid_decode != rc_in.timestamp_last_signal) {
			// we have a new PPM frame. Publish it.
			rc_in.channel_count = ppm_decoded_channels;

			if (rc_in.channel_count > RC_INPUT_MAX_CHANNELS) {
				rc_in.channel_count = RC_INPUT_MAX_CHANNELS;
			}

			for (uint8_t i = 0; i < rc_in.channel_count; i++) {
				rc_in.values[i] = ppm_buffer[i];
			}

			rc_in.timestamp_publication = ppm_last_valid_decode;
			rc_in.timestamp_last_signal = ppm_last_valid_decode;

			rc_in.rc_ppm_frame_length = ppm_frame_length;
			rc_in.rssi = RC_INPUT_RSSI_MAX;
			rc_in.rc_failsafe = false;
			rc_in.rc_lost = false;
			rc_in.rc_lost_frame_count = 0;
			rc_in.rc_total_frame_count = 0;

			/* lazily advertise on first publication */
			if (to_input_rc == 0) {
				to_input_rc = orb_advertise(ORB_ID(input_rc), &rc_in);

			} else {
				orb_publish(ORB_ID(input_rc), to_input_rc, &rc_in);
			}
		}

#endif

	}

	for (unsigned i = 0; i < NUM_ACTUATOR_CONTROL_GROUPS; i++) {
		if (_control_subs[i] > 0) {
			::close(_control_subs[i]);
			_control_subs[i] = -1;
		}
	}
	::close(_armed_sub);

	/* make sure servos are off */
	up_pwm_servo_deinit();

	log("stopping");

	/* note - someone else is responsible for restoring the GPIO config */

	/* tell the dtor that we are exiting */
	_task = -1;
	_exit(0);
}

int
PX4FMU::control_callback(uintptr_t handle,
			 uint8_t control_group,
			 uint8_t control_index,
			 float &input)
{
	const actuator_controls_s *controls = (actuator_controls_s *)handle;

	input = controls[control_group].control[control_index];
	return 0;
}

int
PX4FMU::ioctl(file *filp, int cmd, unsigned long arg)
{
	int ret;

	// XXX disabled, confusing users
	//debug("ioctl 0x%04x 0x%08x", cmd, arg);

	/* try it as a GPIO ioctl first */
	ret = gpio_ioctl(filp, cmd, arg);

	if (ret != -ENOTTY)
		return ret;

	/* if we are in valid PWM mode, try it as a PWM ioctl as well */
	switch (_mode) {
	case MODE_2PWM:
	case MODE_4PWM:
	case MODE_6PWM:
#ifdef CONFIG_ARCH_BOARD_AEROCORE
	case MODE_8PWM:
#endif
		ret = pwm_ioctl(filp, cmd, arg);
		break;

	default:
		debug("not in a PWM mode");
		break;
	}

	/* if nobody wants it, let CDev have it */
	if (ret == -ENOTTY)
		ret = CDev::ioctl(filp, cmd, arg);

	return ret;
}

int
PX4FMU::pwm_ioctl(file *filp, int cmd, unsigned long arg)
{
	int ret = OK;

	lock();

	switch (cmd) {
	case PWM_SERVO_ARM:
		up_pwm_servo_arm(true);
		break;

	case PWM_SERVO_SET_ARM_OK:
	case PWM_SERVO_CLEAR_ARM_OK:
	case PWM_SERVO_SET_FORCE_SAFETY_OFF:
		// these are no-ops, as no safety switch
		break;

	case PWM_SERVO_DISARM:
		up_pwm_servo_arm(false);
		break;

	case PWM_SERVO_GET_DEFAULT_UPDATE_RATE:
		*(uint32_t *)arg = _pwm_default_rate;
		break;

	case PWM_SERVO_SET_UPDATE_RATE:
		ret = set_pwm_rate(_pwm_alt_rate_channels, _pwm_default_rate, arg);
		break;

	case PWM_SERVO_GET_UPDATE_RATE:
		*(uint32_t *)arg = _pwm_alt_rate;
		break;

	case PWM_SERVO_SET_SELECT_UPDATE_RATE:
		ret = set_pwm_rate(arg, _pwm_default_rate, _pwm_alt_rate);
		break;

	case PWM_SERVO_GET_SELECT_UPDATE_RATE:
		*(uint32_t *)arg = _pwm_alt_rate_channels;
		break;

	case PWM_SERVO_SET_FAILSAFE_PWM: {
			struct pwm_output_values *pwm = (struct pwm_output_values *)arg;

			/* discard if too many values are sent */
			if (pwm->channel_count > _max_actuators) {
				ret = -EINVAL;
				break;
			}

			for (unsigned i = 0; i < pwm->channel_count; i++) {
				if (pwm->values[i] == 0) {
					/* ignore 0 */
				} else if (pwm->values[i] > PWM_HIGHEST_MAX) {
					_failsafe_pwm[i] = PWM_HIGHEST_MAX;

				} else if (pwm->values[i] < PWM_LOWEST_MIN) {
					_failsafe_pwm[i] = PWM_LOWEST_MIN;

				} else {
					_failsafe_pwm[i] = pwm->values[i];
				}
			}

			/*
			 * update the counter
			 * this is needed to decide if disarmed PWM output should be turned on or not
			 */
			_num_failsafe_set = 0;

			for (unsigned i = 0; i < _max_actuators; i++) {
				if (_failsafe_pwm[i] > 0)
					_num_failsafe_set++;
			}

			break;
		}

	case PWM_SERVO_GET_FAILSAFE_PWM: {
			struct pwm_output_values *pwm = (struct pwm_output_values *)arg;

			for (unsigned i = 0; i < _max_actuators; i++) {
				pwm->values[i] = _failsafe_pwm[i];
			}

			pwm->channel_count = _max_actuators;
			break;
		}

	case PWM_SERVO_SET_DISARMED_PWM: {
			struct pwm_output_values *pwm = (struct pwm_output_values *)arg;

			/* discard if too many values are sent */
			if (pwm->channel_count > _max_actuators) {
				ret = -EINVAL;
				break;
			}

			for (unsigned i = 0; i < pwm->channel_count; i++) {
				if (pwm->values[i] == 0) {
					/* ignore 0 */
				} else if (pwm->values[i] > PWM_HIGHEST_MAX) {
					_disarmed_pwm[i] = PWM_HIGHEST_MAX;

				} else if (pwm->values[i] < PWM_LOWEST_MIN) {
					_disarmed_pwm[i] = PWM_LOWEST_MIN;

				} else {
					_disarmed_pwm[i] = pwm->values[i];
				}
			}

			/*
			 * update the counter
			 * this is needed to decide if disarmed PWM output should be turned on or not
			 */
			_num_disarmed_set = 0;

			for (unsigned i = 0; i < _max_actuators; i++) {
				if (_disarmed_pwm[i] > 0)
					_num_disarmed_set++;
			}

			break;
		}

	case PWM_SERVO_GET_DISARMED_PWM: {
			struct pwm_output_values *pwm = (struct pwm_output_values *)arg;

			for (unsigned i = 0; i < _max_actuators; i++) {
				pwm->values[i] = _disarmed_pwm[i];
			}

			pwm->channel_count = _max_actuators;
			break;
		}

	case PWM_SERVO_SET_MIN_PWM: {
			struct pwm_output_values *pwm = (struct pwm_output_values *)arg;

			/* discard if too many values are sent */
			if (pwm->channel_count > _max_actuators) {
				ret = -EINVAL;
				break;
			}

			for (unsigned i = 0; i < pwm->channel_count; i++) {
				if (pwm->values[i] == 0) {
					/* ignore 0 */
				} else if (pwm->values[i] > PWM_HIGHEST_MIN) {
					_min_pwm[i] = PWM_HIGHEST_MIN;

				} else if (pwm->values[i] < PWM_LOWEST_MIN) {
					_min_pwm[i] = PWM_LOWEST_MIN;

				} else {
					_min_pwm[i] = pwm->values[i];
				}
			}

			break;
		}

	case PWM_SERVO_GET_MIN_PWM: {
			struct pwm_output_values *pwm = (struct pwm_output_values *)arg;

			for (unsigned i = 0; i < _max_actuators; i++) {
				pwm->values[i] = _min_pwm[i];
			}

			pwm->channel_count = _max_actuators;
			arg = (unsigned long)&pwm;
			break;
		}

	case PWM_SERVO_SET_MAX_PWM: {
			struct pwm_output_values *pwm = (struct pwm_output_values *)arg;

			/* discard if too many values are sent */
			if (pwm->channel_count > _max_actuators) {
				ret = -EINVAL;
				break;
			}

			for (unsigned i = 0; i < pwm->channel_count; i++) {
				if (pwm->values[i] == 0) {
					/* ignore 0 */
				} else if (pwm->values[i] < PWM_LOWEST_MAX) {
					_max_pwm[i] = PWM_LOWEST_MAX;

				} else if (pwm->values[i] > PWM_HIGHEST_MAX) {
					_max_pwm[i] = PWM_HIGHEST_MAX;

				} else {
					_max_pwm[i] = pwm->values[i];
				}
			}

			break;
		}

	case PWM_SERVO_GET_MAX_PWM: {
			struct pwm_output_values *pwm = (struct pwm_output_values *)arg;

			for (unsigned i = 0; i < _max_actuators; i++) {
				pwm->values[i] = _max_pwm[i];
			}

			pwm->channel_count = _max_actuators;
			arg = (unsigned long)&pwm;
			break;
		}

#ifdef CONFIG_ARCH_BOARD_AEROCORE
	case PWM_SERVO_SET(7):
	case PWM_SERVO_SET(6):
		if (_mode < MODE_8PWM) {
			ret = -EINVAL;
			break;
		}
#endif

	case PWM_SERVO_SET(5):
	case PWM_SERVO_SET(4):
		if (_mode < MODE_6PWM) {
			ret = -EINVAL;
			break;
		}

	/* FALLTHROUGH */
	case PWM_SERVO_SET(3):
	case PWM_SERVO_SET(2):
		if (_mode < MODE_4PWM) {
			ret = -EINVAL;
			break;
		}

	/* FALLTHROUGH */
	case PWM_SERVO_SET(1):
	case PWM_SERVO_SET(0):
		if (arg <= 2100) {
			up_pwm_servo_set(cmd - PWM_SERVO_SET(0), arg);

		} else {
			ret = -EINVAL;
		}

		break;

#ifdef CONFIG_ARCH_BOARD_AEROCORE
	case PWM_SERVO_GET(7):
	case PWM_SERVO_GET(6):
		if (_mode < MODE_8PWM) {
			ret = -EINVAL;
			break;
		}
#endif

	case PWM_SERVO_GET(5):
	case PWM_SERVO_GET(4):
		if (_mode < MODE_6PWM) {
			ret = -EINVAL;
			break;
		}

	/* FALLTHROUGH */
	case PWM_SERVO_GET(3):
	case PWM_SERVO_GET(2):
		if (_mode < MODE_4PWM) {
			ret = -EINVAL;
			break;
		}

	/* FALLTHROUGH */
	case PWM_SERVO_GET(1):
	case PWM_SERVO_GET(0):
		*(servo_position_t *)arg = up_pwm_servo_get(cmd - PWM_SERVO_GET(0));
		break;

	case PWM_SERVO_GET_RATEGROUP(0):
	case PWM_SERVO_GET_RATEGROUP(1):
	case PWM_SERVO_GET_RATEGROUP(2):
	case PWM_SERVO_GET_RATEGROUP(3):
	case PWM_SERVO_GET_RATEGROUP(4):
	case PWM_SERVO_GET_RATEGROUP(5):
#ifdef CONFIG_ARCH_BOARD_AEROCORE
	case PWM_SERVO_GET_RATEGROUP(6):
	case PWM_SERVO_GET_RATEGROUP(7):
#endif
		*(uint32_t *)arg = up_pwm_servo_get_rate_group(cmd - PWM_SERVO_GET_RATEGROUP(0));
		break;

	case PWM_SERVO_GET_COUNT:
	case MIXERIOCGETOUTPUTCOUNT:
		switch (_mode) {
#ifdef CONFIG_ARCH_BOARD_AEROCORE
		case MODE_8PWM:
			*(unsigned *)arg = 8;
			break;
#endif

		case MODE_6PWM:
			*(unsigned *)arg = 6;
			break;

		case MODE_4PWM:
			*(unsigned *)arg = 4;
			break;

		case MODE_2PWM:
			*(unsigned *)arg = 2;
			break;

		default:
			ret = -EINVAL;
			break;
		}

		break;

	case PWM_SERVO_SET_COUNT: {
		/* change the number of outputs that are enabled for
		 * PWM. This is used to change the split between GPIO
		 * and PWM under control of the flight config
		 * parameters. Note that this does not allow for
		 * changing a set of pins to be used for serial on
		 * FMUv1 
		 */
		switch (arg) {
		case 0:
			set_mode(MODE_NONE);
			break;

		case 2:
			set_mode(MODE_2PWM);
			break;

		case 4:
			set_mode(MODE_4PWM);
			break;

#if defined(CONFIG_ARCH_BOARD_PX4FMU_V2)
		case 6:
			set_mode(MODE_6PWM);
			break;
#endif
#if defined(CONFIG_ARCH_BOARD_AEROCORE)
		case 8:
			set_mode(MODE_8PWM);
			break;
#endif

		default:
			ret = -EINVAL;
			break;
		}
		break;
	}

	case MIXERIOCRESET:
		if (_mixers != nullptr) {
			delete _mixers;
			_mixers = nullptr;
			_groups_required = 0;
		}

		break;

	case MIXERIOCADDSIMPLE: {
			mixer_simple_s *mixinfo = (mixer_simple_s *)arg;

			SimpleMixer *mixer = new SimpleMixer(control_callback,
							     (uintptr_t)_controls, mixinfo);

			if (mixer->check()) {
				delete mixer;
				_groups_required = 0;
				ret = -EINVAL;

			} else {
				if (_mixers == nullptr)
					_mixers = new MixerGroup(control_callback,
								 (uintptr_t)_controls);

				_mixers->add_mixer(mixer);
				_mixers->groups_required(_groups_required);
			}

			break;
		}

	case MIXERIOCLOADBUF: {
			const char *buf = (const char *)arg;
			unsigned buflen = strnlen(buf, 1024);

			if (_mixers == nullptr)
				_mixers = new MixerGroup(control_callback, (uintptr_t)_controls);

			if (_mixers == nullptr) {
				_groups_required = 0;
				ret = -ENOMEM;

			} else {

				ret = _mixers->load_from_buf(buf, buflen);

				if (ret != 0) {
					debug("mixer load failed with %d", ret);
					delete _mixers;
					_mixers = nullptr;
					_groups_required = 0;
					ret = -EINVAL;
				} else {

					_mixers->groups_required(_groups_required);
				}
			}

			break;
		}

	default:
		ret = -ENOTTY;
		break;
	}

	unlock();

	return ret;
}

/*
  this implements PWM output via a write() method, for compatibility
  with px4io
 */
ssize_t
PX4FMU::write(file *filp, const char *buffer, size_t len)
{
	unsigned count = len / 2;
	uint16_t values[6];

#ifdef CONFIG_ARCH_BOARD_AEROCORE
	if (count > 8) {
		// we have at most 8 outputs
		count = 8;
	}
#else
	if (count > 6) {
		// we have at most 6 outputs
		count = 6;
	}
#endif

	// allow for misaligned values
	memcpy(values, buffer, count * 2);

	for (uint8_t i = 0; i < count; i++) {
		up_pwm_servo_set(i, values[i]);
	}

	return count * 2;
}

void
PX4FMU::sensor_reset(int ms)
{
#if defined(CONFIG_ARCH_BOARD_PX4FMU_V2)

	if (ms < 1) {
		ms = 1;
	}

	/* disable SPI bus */
	stm32_configgpio(GPIO_SPI_CS_GYRO_OFF);
	stm32_configgpio(GPIO_SPI_CS_ACCEL_MAG_OFF);
	stm32_configgpio(GPIO_SPI_CS_BARO_OFF);
	stm32_configgpio(GPIO_SPI_CS_MPU_OFF);

	stm32_gpiowrite(GPIO_SPI_CS_GYRO_OFF, 0);
	stm32_gpiowrite(GPIO_SPI_CS_ACCEL_MAG_OFF, 0);
	stm32_gpiowrite(GPIO_SPI_CS_BARO_OFF, 0);
	stm32_gpiowrite(GPIO_SPI_CS_MPU_OFF, 0);

	stm32_configgpio(GPIO_SPI1_SCK_OFF);
	stm32_configgpio(GPIO_SPI1_MISO_OFF);
	stm32_configgpio(GPIO_SPI1_MOSI_OFF);

	stm32_gpiowrite(GPIO_SPI1_SCK_OFF, 0);
	stm32_gpiowrite(GPIO_SPI1_MISO_OFF, 0);
	stm32_gpiowrite(GPIO_SPI1_MOSI_OFF, 0);

	stm32_configgpio(GPIO_GYRO_DRDY_OFF);
	stm32_configgpio(GPIO_MAG_DRDY_OFF);
	stm32_configgpio(GPIO_ACCEL_DRDY_OFF);
	stm32_configgpio(GPIO_EXTI_MPU_DRDY_OFF);

	stm32_gpiowrite(GPIO_GYRO_DRDY_OFF, 0);
	stm32_gpiowrite(GPIO_MAG_DRDY_OFF, 0);
	stm32_gpiowrite(GPIO_ACCEL_DRDY_OFF, 0);
	stm32_gpiowrite(GPIO_EXTI_MPU_DRDY_OFF, 0);

	/* set the sensor rail off */
	stm32_configgpio(GPIO_VDD_3V3_SENSORS_EN);
	stm32_gpiowrite(GPIO_VDD_3V3_SENSORS_EN, 0);

	/* wait for the sensor rail to reach GND */
	usleep(ms * 1000);
	warnx("reset done, %d ms", ms);

	/* re-enable power */

	/* switch the sensor rail back on */
	stm32_gpiowrite(GPIO_VDD_3V3_SENSORS_EN, 1);

	/* wait a bit before starting SPI, different times didn't influence results */
	usleep(100);

	/* reconfigure the SPI pins */
#ifdef CONFIG_STM32_SPI1
	stm32_configgpio(GPIO_SPI_CS_GYRO);
	stm32_configgpio(GPIO_SPI_CS_ACCEL_MAG);
	stm32_configgpio(GPIO_SPI_CS_BARO);
	stm32_configgpio(GPIO_SPI_CS_MPU);

	/* De-activate all peripherals,
	 * required for some peripheral
	 * state machines
	 */
	stm32_gpiowrite(GPIO_SPI_CS_GYRO, 1);
	stm32_gpiowrite(GPIO_SPI_CS_ACCEL_MAG, 1);
	stm32_gpiowrite(GPIO_SPI_CS_BARO, 1);
	stm32_gpiowrite(GPIO_SPI_CS_MPU, 1);

	// // XXX bring up the EXTI pins again
	// stm32_configgpio(GPIO_GYRO_DRDY);
	// stm32_configgpio(GPIO_MAG_DRDY);
	// stm32_configgpio(GPIO_ACCEL_DRDY);
	// stm32_configgpio(GPIO_EXTI_MPU_DRDY);

#endif
#endif
}


void
PX4FMU::gpio_reset(void)
{
	/*
	 * Setup default GPIO config - all pins as GPIOs, input if
	 * possible otherwise output if possible.
	 */
	for (unsigned i = 0; i < _ngpio; i++) {
		if (_gpio_tab[i].input != 0) {
			stm32_configgpio(_gpio_tab[i].input);

		} else if (_gpio_tab[i].output != 0) {
			stm32_configgpio(_gpio_tab[i].output);
		}
	}

#if defined(CONFIG_ARCH_BOARD_PX4FMU_V1)
	/* if we have a GPIO direction control, set it to zero (input) */
	stm32_gpiowrite(GPIO_GPIO_DIR, 0);
	stm32_configgpio(GPIO_GPIO_DIR);
#endif
}

void
PX4FMU::gpio_set_function(uint32_t gpios, int function)
{
#if defined(CONFIG_ARCH_BOARD_PX4FMU_V1)

	/*
	 * GPIOs 0 and 1 must have the same direction as they are buffered
	 * by a shared 2-port driver.  Any attempt to set either sets both.
	 */
	if (gpios & 3) {
		gpios |= 3;

		/* flip the buffer to output mode if required */
		if (GPIO_SET_OUTPUT == function)
			stm32_gpiowrite(GPIO_GPIO_DIR, 1);
	}

#endif

	/* configure selected GPIOs as required */
	for (unsigned i = 0; i < _ngpio; i++) {
		if (gpios & (1 << i)) {
			switch (function) {
			case GPIO_SET_INPUT:
				stm32_configgpio(_gpio_tab[i].input);
				break;

			case GPIO_SET_OUTPUT:
				stm32_configgpio(_gpio_tab[i].output);
				break;

			case GPIO_SET_ALT_1:
				if (_gpio_tab[i].alt != 0)
					stm32_configgpio(_gpio_tab[i].alt);

				break;
			}
		}
	}

#if defined(CONFIG_ARCH_BOARD_PX4FMU_V1)

	/* flip buffer to input mode if required */
	if ((GPIO_SET_INPUT == function) && (gpios & 3))
		stm32_gpiowrite(GPIO_GPIO_DIR, 0);

#endif
}

void
PX4FMU::gpio_write(uint32_t gpios, int function)
{
	int value = (function == GPIO_SET) ? 1 : 0;

	for (unsigned i = 0; i < _ngpio; i++)
		if (gpios & (1 << i))
			stm32_gpiowrite(_gpio_tab[i].output, value);
}

uint32_t
PX4FMU::gpio_read(void)
{
	uint32_t bits = 0;

	for (unsigned i = 0; i < _ngpio; i++)
		if (stm32_gpioread(_gpio_tab[i].input))
			bits |= (1 << i);

	return bits;
}

int
PX4FMU::gpio_ioctl(struct file *filp, int cmd, unsigned long arg)
{
	int	ret = OK;

	lock();

	switch (cmd) {

	case GPIO_RESET:
		gpio_reset();
		break;

	case GPIO_SENSOR_RAIL_RESET:
		sensor_reset(arg);
		break;

	case GPIO_SET_OUTPUT:
	case GPIO_SET_INPUT:
	case GPIO_SET_ALT_1:
		gpio_set_function(arg, cmd);
		break;

	case GPIO_SET_ALT_2:
	case GPIO_SET_ALT_3:
	case GPIO_SET_ALT_4:
		ret = -EINVAL;
		break;

	case GPIO_SET:
	case GPIO_CLEAR:
		gpio_write(arg, cmd);
		break;

	case GPIO_GET:
		*(uint32_t *)arg = gpio_read();
		break;

	default:
		ret = -ENOTTY;
	}

	unlock();

	return ret;
}

namespace
{

enum PortMode {
	PORT_MODE_UNSET = 0,
	PORT_FULL_GPIO,
	PORT_FULL_SERIAL,
	PORT_FULL_PWM,
	PORT_GPIO_AND_SERIAL,
	PORT_PWM_AND_SERIAL,
	PORT_PWM_AND_GPIO,
};

PortMode g_port_mode;

int
fmu_new_mode(PortMode new_mode)
{
	uint32_t gpio_bits;
	PX4FMU::Mode servo_mode;

	/* reset to all-inputs */
	g_fmu->ioctl(0, GPIO_RESET, 0);

	gpio_bits = 0;
	servo_mode = PX4FMU::MODE_NONE;

	switch (new_mode) {
	case PORT_FULL_GPIO:
	case PORT_MODE_UNSET:
		/* nothing more to do here */
		break;

	case PORT_FULL_PWM:
#if defined(CONFIG_ARCH_BOARD_PX4FMU_V1)
		/* select 4-pin PWM mode */
		servo_mode = PX4FMU::MODE_4PWM;
#endif
#if defined(CONFIG_ARCH_BOARD_PX4FMU_V2)
		servo_mode = PX4FMU::MODE_6PWM;
#endif
#if defined(CONFIG_ARCH_BOARD_AEROCORE)
		servo_mode = PX4FMU::MODE_8PWM;
#endif
		break;

		/* mixed modes supported on v1 board only */
#if defined(CONFIG_ARCH_BOARD_PX4FMU_V1)

	case PORT_FULL_SERIAL:
		/* set all multi-GPIOs to serial mode */
		gpio_bits = GPIO_MULTI_1 | GPIO_MULTI_2 | GPIO_MULTI_3 | GPIO_MULTI_4;
		break;

	case PORT_GPIO_AND_SERIAL:
		/* set RX/TX multi-GPIOs to serial mode */
		gpio_bits = GPIO_MULTI_3 | GPIO_MULTI_4;
		break;

	case PORT_PWM_AND_SERIAL:
		/* select 2-pin PWM mode */
		servo_mode = PX4FMU::MODE_2PWM;
		/* set RX/TX multi-GPIOs to serial mode */
		gpio_bits = GPIO_MULTI_3 | GPIO_MULTI_4;
		break;

	case PORT_PWM_AND_GPIO:
		/* select 2-pin PWM mode */
		servo_mode = PX4FMU::MODE_2PWM;
		break;
#endif

	default:
		return -1;
	}

	/* adjust GPIO config for serial mode(s) */
	if (gpio_bits != 0)
		g_fmu->ioctl(0, GPIO_SET_ALT_1, gpio_bits);

	/* (re)set the PWM output mode */
	g_fmu->set_mode(servo_mode);

	return OK;
}

int
fmu_start(void)
{
	int ret = OK;

	if (g_fmu == nullptr) {

		g_fmu = new PX4FMU;

		if (g_fmu == nullptr) {
			ret = -ENOMEM;

		} else {
			ret = g_fmu->init();

			if (ret != OK) {
				delete g_fmu;
				g_fmu = nullptr;
			}
		}
	}

	return ret;
}

int
fmu_stop(void)
{
	int ret = OK;

	if (g_fmu != nullptr) {

		delete g_fmu;
		g_fmu = nullptr;
	}

	return ret;
}

void
sensor_reset(int ms)
{
	int	 fd;

	fd = open(PX4FMU_DEVICE_PATH, O_RDWR);

	if (fd < 0)
		errx(1, "open fail");

	if (ioctl(fd, GPIO_SENSOR_RAIL_RESET, ms) < 0)
		err(1, "servo arm failed");

}

void
test(void)
{
	int	 fd;
	unsigned servo_count = 0;
	unsigned pwm_value = 1000;
	int	 direction = 1;
	int	 ret;

	fd = open(PX4FMU_DEVICE_PATH, O_RDWR);

	if (fd < 0)
		errx(1, "open fail");

	if (ioctl(fd, PWM_SERVO_ARM, 0) < 0)       err(1, "servo arm failed");

	if (ioctl(fd, PWM_SERVO_GET_COUNT, (unsigned long)&servo_count) != 0) {
		err(1, "Unable to get servo count\n");
	}

	warnx("Testing %u servos", (unsigned)servo_count);

	struct pollfd fds;
	fds.fd = 0; /* stdin */
	fds.events = POLLIN;

	warnx("Press CTRL-C or 'c' to abort.");

	for (;;) {
		/* sweep all servos between 1000..2000 */
		servo_position_t servos[servo_count];

		for (unsigned i = 0; i < servo_count; i++)
			servos[i] = pwm_value;

		if (direction == 1) {
			// use ioctl interface for one direction
			for (unsigned i = 0; i < servo_count;	i++) {
				if (ioctl(fd, PWM_SERVO_SET(i), servos[i]) < 0) {
					err(1, "servo %u set failed", i);
				}
			}

		} else {
			// and use write interface for the other direction
			ret = write(fd, servos, sizeof(servos));

			if (ret != (int)sizeof(servos))
				err(1, "error writing PWM servo data, wrote %u got %d", sizeof(servos), ret);
		}

		if (direction > 0) {
			if (pwm_value < 2000) {
				pwm_value++;

			} else {
				direction = -1;
			}

		} else {
			if (pwm_value > 1000) {
				pwm_value--;

			} else {
				direction = 1;
			}
		}

		/* readback servo values */
		for (unsigned i = 0; i < servo_count; i++) {
			servo_position_t value;

			if (ioctl(fd, PWM_SERVO_GET(i), (unsigned long)&value))
				err(1, "error reading PWM servo %d", i);

			if (value != servos[i])
				errx(1, "servo %d readback error, got %u expected %u", i, value, servos[i]);
		}

		/* Check if user wants to quit */
		char c;
		ret = poll(&fds, 1, 0);

		if (ret > 0) {

			read(0, &c, 1);

			if (c == 0x03 || c == 0x63 || c == 'q') {
				warnx("User abort\n");
				break;
			}
		}
	}

	close(fd);

	exit(0);
}

void
fake(int argc, char *argv[])
{
	if (argc < 5)
		errx(1, "fmu fake <roll> <pitch> <yaw> <thrust> (values -100 .. 100)");

	actuator_controls_s ac;

	ac.control[0] = strtol(argv[1], 0, 0) / 100.0f;

	ac.control[1] = strtol(argv[2], 0, 0) / 100.0f;

	ac.control[2] = strtol(argv[3], 0, 0) / 100.0f;

	ac.control[3] = strtol(argv[4], 0, 0) / 100.0f;

	orb_advert_t handle = orb_advertise(ORB_ID_VEHICLE_ATTITUDE_CONTROLS, &ac);

	if (handle < 0)
		errx(1, "advertise failed");

	actuator_armed_s aa;

	aa.armed = true;
	aa.lockdown = false;

	handle = orb_advertise(ORB_ID(actuator_armed), &aa);

	if (handle < 0)
		errx(1, "advertise failed 2");

	exit(0);
}

} // namespace

extern "C" __EXPORT int fmu_main(int argc, char *argv[]);

int
fmu_main(int argc, char *argv[])
{
	PortMode new_mode = PORT_MODE_UNSET;
	const char *verb = argv[1];

	if (!strcmp(verb, "stop")) {
		fmu_stop();
		errx(0, "FMU driver stopped");
	}

	if (!strcmp(verb, "id")) {
		uint8_t id[12];
		(void)get_board_serial(id);

		errx(0, "Board serial:\n %02X%02X%02X%02X %02X%02X%02X%02X %02X%02X%02X%02X",
		     (unsigned)id[0], (unsigned)id[1], (unsigned)id[2], (unsigned)id[3], (unsigned)id[4], (unsigned)id[5],
		     (unsigned)id[6], (unsigned)id[7], (unsigned)id[8], (unsigned)id[9], (unsigned)id[10], (unsigned)id[11]);
	}


	if (fmu_start() != OK)
		errx(1, "failed to start the FMU driver");

	/*
	 * Mode switches.
	 */
	if (!strcmp(verb, "mode_gpio")) {
		new_mode = PORT_FULL_GPIO;

	} else if (!strcmp(verb, "mode_pwm")) {
		new_mode = PORT_FULL_PWM;

#if defined(CONFIG_ARCH_BOARD_PX4FMU_V1)

	} else if (!strcmp(verb, "mode_serial")) {
		new_mode = PORT_FULL_SERIAL;

	} else if (!strcmp(verb, "mode_gpio_serial")) {
		new_mode = PORT_GPIO_AND_SERIAL;

	} else if (!strcmp(verb, "mode_pwm_serial")) {
		new_mode = PORT_PWM_AND_SERIAL;

	} else if (!strcmp(verb, "mode_pwm_gpio")) {
		new_mode = PORT_PWM_AND_GPIO;
#endif
	}

	/* was a new mode set? */
	if (new_mode != PORT_MODE_UNSET) {

		/* yes but it's the same mode */
		if (new_mode == g_port_mode)
			return OK;

		/* switch modes */
		int ret = fmu_new_mode(new_mode);
		exit(ret == OK ? 0 : 1);
	}

	if (!strcmp(verb, "test"))
		test();

	if (!strcmp(verb, "fake"))
		fake(argc - 1, argv + 1);

	if (!strcmp(verb, "sensor_reset")) {
		if (argc > 2) {
			int reset_time = strtol(argv[2], 0, 0);
			sensor_reset(reset_time);

		} else {
			sensor_reset(0);
			warnx("resettet default time");
		}

		exit(0);
	}


	fprintf(stderr, "FMU: unrecognised command %s, try:\n", verb);
#if defined(CONFIG_ARCH_BOARD_PX4FMU_V1)
	fprintf(stderr, "  mode_gpio, mode_serial, mode_pwm, mode_gpio_serial, mode_pwm_serial, mode_pwm_gpio, test\n");
#elif defined(CONFIG_ARCH_BOARD_PX4FMU_V2) || defined(CONFIG_ARCH_BOARD_AEROCORE)
	fprintf(stderr, "  mode_gpio, mode_pwm, test, sensor_reset [milliseconds]\n");
#endif
	exit(1);
}