px4io.cpp

/****************************************************************************
 *
 *   Copyright (c) 2012-2014 PX4 Development Team. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name PX4 nor the names of its contributors may be
 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 ****************************************************************************/

/**
 * @file px4io.cpp
 * Driver for the PX4IO board.
 *
 * PX4IO is connected via I2C or DMA enabled high-speed UART.
 */

#include <nuttx/config.h>

#include <sys/types.h>
#include <stdint.h>
#include <stdbool.h>
#include <assert.h>
#include <debug.h>
#include <time.h>
#include <queue.h>
#include <errno.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <math.h>
#include <crc32.h>

#include <arch/board/board.h>

#include <drivers/device/device.h>
#include <drivers/drv_rc_input.h>
#include <drivers/drv_pwm_output.h>
#include <drivers/drv_sbus.h>
#include <drivers/drv_gpio.h>
#include <drivers/drv_hrt.h>
#include <drivers/drv_mixer.h>

#include <systemlib/mixer/mixer.h>
#include <systemlib/perf_counter.h>
#include <systemlib/err.h>
#include <systemlib/systemlib.h>
#include <systemlib/scheduling_priorities.h>
#include <systemlib/param/param.h>
#include <systemlib/circuit_breaker.h>

#include <uORB/topics/actuator_controls.h>
#include <uORB/topics/actuator_outputs.h>
#include <uORB/topics/actuator_armed.h>
#include <uORB/topics/safety.h>
#include <uORB/topics/vehicle_control_mode.h>
#include <uORB/topics/vehicle_command.h>
#include <uORB/topics/rc_channels.h>
#include <uORB/topics/battery_status.h>
#include <uORB/topics/servorail_status.h>
#include <uORB/topics/parameter_update.h>

#include <debug.h>

#include <mavlink/mavlink_log.h>
#include <modules/px4iofirmware/protocol.h>

#include "uploader.h"

#include "modules/dataman/dataman.h"

extern device::Device *PX4IO_i2c_interface() weak_function;
extern device::Device *PX4IO_serial_interface() weak_function;

#define PX4IO_SET_DEBUG			_IOC(0xff00, 0)
#define PX4IO_INAIR_RESTART_ENABLE	_IOC(0xff00, 1)
#define PX4IO_REBOOT_BOOTLOADER		_IOC(0xff00, 2)
#define PX4IO_CHECK_CRC			_IOC(0xff00, 3)

#define UPDATE_INTERVAL_MIN		2			// 2 ms	-> 500 Hz
#define ORB_CHECK_INTERVAL		200000		// 200 ms -> 5 Hz
#define IO_POLL_INTERVAL		20000		// 20 ms -> 50 Hz

/**
 * The PX4IO class.
 *
 * Encapsulates PX4FMU to PX4IO communications modeled as file operations.
 */
class PX4IO : public device::CDev
{
public:
	/**
	 * Constructor.
	 *
	 * Initialize all class variables.
	 */
	PX4IO(device::Device *interface);

	/**
	 * Destructor.
	 *
	 * Wait for worker thread to terminate.
	 */
	virtual ~PX4IO();

	/**
	 * Initialize the PX4IO class.
	 *
	 * Retrieve relevant initial system parameters. Initialize PX4IO registers.
	 */
	virtual int		init();

	/**
	 * Initialize the PX4IO class.
	 *
	 * Retrieve relevant initial system parameters. Initialize PX4IO registers.
	 *
	 * @param disable_rc_handling set to true to forbid override / RC handling on IO
	 */
	int			init(bool disable_rc_handling);

	/**
	 * Detect if a PX4IO is connected.
	 *
	 * Only validate if there is a PX4IO to talk to.
	 */
	virtual int		detect();

	/**
	 * IO Control handler.
	 *
	 * Handle all IOCTL calls to the PX4IO file descriptor.
	 *
	 * @param[in] filp file handle (not used). This function is always called directly through object reference
	 * @param[in] cmd the IOCTL command
	 * @param[in] the IOCTL command parameter (optional)
	 */
	virtual int		ioctl(file *filp, int cmd, unsigned long arg);

	/**
	 * write handler.
	 *
	 * Handle writes to the PX4IO file descriptor.
	 *
	 * @param[in] filp file handle (not used). This function is always called directly through object reference
	 * @param[in] buffer pointer to the data buffer to be written
	 * @param[in] len size in bytes to be written
	 * @return number of bytes written
	 */
	virtual ssize_t		write(file *filp, const char *buffer, size_t len);

	/**
	* Set the update rate for actuator outputs from FMU to IO.
	*
	* @param[in] rate		The rate in Hz actuator outpus are sent to IO.
	* 			Min 10 Hz, max 400 Hz
	*/
	int      		set_update_rate(int rate);

	/**
	* Set the battery current scaling and bias
	*
	* @param[in] amp_per_volt
	* @param[in] amp_bias
	*/
	void      		set_battery_current_scaling(float amp_per_volt, float amp_bias);

	/**
	 * Push failsafe values to IO.
	 *
	 * @param[in] vals	Failsafe control inputs: in us PPM (900 for zero, 1500 for centered, 2100 for full)
	 * @param[in] len	Number of channels, could up to 8
	 */
	int			set_failsafe_values(const uint16_t *vals, unsigned len);

	/**
	 * Disable RC input handling
	 */
	int			disable_rc_handling();

	/**
	 * Print IO status.
	 *
	 * Print all relevant IO status information
	 *
	 * @param extended_status Shows more verbose information (in particular RC config)
	 */
	void			print_status(bool extended_status);

	/**
	 * Fetch and print debug console output.
	 */
	int			print_debug();

#ifdef CONFIG_ARCH_BOARD_PX4FMU_V1
	/**
	 * Set the DSM VCC is controlled by relay one flag
	 *
	 * @param[in] enable true=DSM satellite VCC is controlled by relay1, false=DSM satellite VCC not controlled
	 */
	inline void		set_dsm_vcc_ctl(bool enable) {
		_dsm_vcc_ctl = enable;
	};

	/**
	 * Get the DSM VCC is controlled by relay one flag
	 *
	 * @return true=DSM satellite VCC is controlled by relay1, false=DSM satellite VCC not controlled
	 */
	inline bool		get_dsm_vcc_ctl() {
		return _dsm_vcc_ctl;
	};
#endif

	inline uint16_t		system_status() const {return _status;}

private:
	device::Device		*_interface;

	// XXX
	unsigned		_hardware;		///< Hardware revision
	unsigned		_max_actuators;		///< Maximum # of actuators supported by PX4IO
	unsigned		_max_controls;		///< Maximum # of controls supported by PX4IO
	unsigned		_max_rc_input;		///< Maximum receiver channels supported by PX4IO
	unsigned		_max_relays;		///< Maximum relays supported by PX4IO
	unsigned		_max_transfer;		///< Maximum number of I2C transfers supported by PX4IO

	unsigned 		_update_interval;	///< Subscription interval limiting send rate
	bool			_rc_handling_disabled;	///< If set, IO does not evaluate, but only forward the RC values
	unsigned		_rc_chan_count;		///< Internal copy of the last seen number of RC channels
	uint64_t		_rc_last_valid;		///< last valid timestamp

	volatile int		_task;			///< worker task id
	volatile bool		_task_should_exit;	///< worker terminate flag

	int			_mavlink_fd;		///< mavlink file descriptor.

	perf_counter_t		_perf_update;		///<local performance counter for status updates
	perf_counter_t		_perf_write;		///<local performance counter for PWM control writes
	perf_counter_t		_perf_chan_count;	///<local performance counter for channel number changes

	/* cached IO state */
	uint16_t		_status;		///< Various IO status flags
	uint16_t		_alarms;		///< Various IO alarms

	/* subscribed topics */
	int			_t_actuator_controls_0;	///< actuator controls group 0 topic
	int			_t_actuator_controls_1;	///< actuator controls group 1 topic
	int			_t_actuator_controls_2;	///< actuator controls group 2 topic
	int			_t_actuator_controls_3;	///< actuator controls group 3 topic
	int			_t_actuator_armed;	///< system armed control topic
	int 			_t_vehicle_control_mode;///< vehicle control mode topic
	int			_t_param;		///< parameter update topic
	int			_t_vehicle_command;	///< vehicle command topic

	/* advertised topics */
	orb_advert_t 		_to_input_rc;		///< rc inputs from io
	orb_advert_t		_to_outputs;		///< mixed servo outputs topic
	orb_advert_t		_to_battery;		///< battery status / voltage
	orb_advert_t		_to_servorail;		///< servorail status
	orb_advert_t		_to_safety;		///< status of safety

	actuator_outputs_s	_outputs;		///< mixed outputs
	servorail_status_s	_servorail_status;	///< servorail status

	bool			_primary_pwm_device;	///< true if we are the default PWM output
	bool			_lockdown_override;	///< allow to override the safety lockdown

	float			_battery_amp_per_volt;	///< current sensor amps/volt
	float			_battery_amp_bias;	///< current sensor bias
	float			_battery_mamphour_total;///< amp hours consumed so far
	uint64_t		_battery_last_timestamp;///< last amp hour calculation timestamp
	bool			_cb_flighttermination;	///< true if the flight termination circuit breaker is enabled

#ifdef CONFIG_ARCH_BOARD_PX4FMU_V1
	bool			_dsm_vcc_ctl;		///< true if relay 1 controls DSM satellite RX power
#endif

	/**
	 * Trampoline to the worker task
	 */
	static void		task_main_trampoline(int argc, char *argv[]);

	/**
	 * worker task
	 */
	void			task_main();

	/**
	 * Send controls for one group to IO
	 */
	int			io_set_control_state(unsigned group);

	/**
	 * Send all controls to IO
	 */
	int			io_set_control_groups();

	/**
	 * Update IO's arming-related state
	 */
	int			io_set_arming_state();

	/**
	 * Push RC channel configuration to IO.
	 */
	int			io_set_rc_config();

	/**
	 * Fetch status and alarms from IO
	 *
	 * Also publishes battery voltage/current.
	 */
	int			io_get_status();

	/**
	 * Disable RC input handling
	 */
	int			io_disable_rc_handling();

	/**
	 * Fetch RC inputs from IO.
	 *
	 * @param input_rc	Input structure to populate.
	 * @return		OK if data was returned.
	 */
	int			io_get_raw_rc_input(rc_input_values &input_rc);

	/**
	 * Fetch and publish raw RC input data.
	 */
	int			io_publish_raw_rc();

	/**
	 * Fetch and publish the PWM servo outputs.
	 */
	int			io_publish_pwm_outputs();

	/**
	 * write register(s)
	 *
	 * @param page		Register page to write to.
	 * @param offset	Register offset to start writing at.
	 * @param values	Pointer to array of values to write.
	 * @param num_values	The number of values to write.
	 * @return		OK if all values were successfully written.
	 */
	int			io_reg_set(uint8_t page, uint8_t offset, const uint16_t *values, unsigned num_values);

	/**
	 * write a register
	 *
	 * @param page		Register page to write to.
	 * @param offset	Register offset to write to.
	 * @param value		Value to write.
	 * @return		OK if the value was written successfully.
	 */
	int			io_reg_set(uint8_t page, uint8_t offset, const uint16_t value);

	/**
	 * read register(s)
	 *
	 * @param page		Register page to read from.
	 * @param offset	Register offset to start reading from.
	 * @param values	Pointer to array where values should be stored.
	 * @param num_values	The number of values to read.
	 * @return		OK if all values were successfully read.
	 */
	int			io_reg_get(uint8_t page, uint8_t offset, uint16_t *values, unsigned num_values);

	/**
	 * read a register
	 *
	 * @param page		Register page to read from.
	 * @param offset	Register offset to start reading from.
	 * @return		Register value that was read, or _io_reg_get_error on error.
	 */
	uint32_t		io_reg_get(uint8_t page, uint8_t offset);
	static const uint32_t	_io_reg_get_error = 0x80000000;

	/**
	 * modify a register
	 *
	 * @param page		Register page to modify.
	 * @param offset	Register offset to modify.
	 * @param clearbits	Bits to clear in the register.
	 * @param setbits	Bits to set in the register.
	 */
	int			io_reg_modify(uint8_t page, uint8_t offset, uint16_t clearbits, uint16_t setbits);

	/**
	 * Send mixer definition text to IO
	 */
	int			mixer_send(const char *buf, unsigned buflen, unsigned retries = 3);

	/**
	 * Handle a status update from IO.
	 *
	 * Publish IO status information if necessary.
	 *
	 * @param status	The status register
	 */
	int			io_handle_status(uint16_t status);

	/**
	 * Handle an alarm update from IO.
	 *
	 * Publish IO alarm information if necessary.
	 *
	 * @param alarm		The status register
	 */
	int			io_handle_alarms(uint16_t alarms);

	/**
	 * Handle issuing dsm bind ioctl to px4io.
	 *
	 * @param dsmMode	0:dsm2, 1:dsmx
	 */
	void			dsm_bind_ioctl(int dsmMode);

	/**
	 * Handle a battery update from IO.
	 *
	 * Publish IO battery information if necessary.
	 *
	 * @param vbatt		vbatt register
	 * @param ibatt		ibatt register
	 */
	void			io_handle_battery(uint16_t vbatt, uint16_t ibatt);

	/**
	 * Handle a servorail update from IO.
	 *
	 * Publish servo rail information if necessary.
	 *
	 * @param vservo	vservo register
	 * @param vrssi 	vrssi register
	 */
	void			io_handle_vservo(uint16_t vservo, uint16_t vrssi);

	/* do not allow to copy this class due to ptr data members */
	PX4IO(const PX4IO&);
	PX4IO operator=(const PX4IO&);
};

namespace
{

PX4IO	*g_dev = nullptr;

}

PX4IO::PX4IO(device::Device *interface) :
	CDev("px4io", PX4IO_DEVICE_PATH),
	_interface(interface),
	_hardware(0),
	_max_actuators(0),
	_max_controls(0),
	_max_rc_input(0),
	_max_relays(0),
	_max_transfer(16),	/* sensible default */
	_update_interval(0),
	_rc_handling_disabled(false),
	_rc_chan_count(0),
	_rc_last_valid(0),
	_task(-1),
	_task_should_exit(false),
	_mavlink_fd(-1),
	_perf_update(perf_alloc(PC_ELAPSED, "io update")),
	_perf_write(perf_alloc(PC_ELAPSED, "io write")),
	_perf_chan_count(perf_alloc(PC_COUNT, "io rc #")),
	_status(0),
	_alarms(0),
	_t_actuator_controls_0(-1),
	_t_actuator_controls_1(-1),
	_t_actuator_controls_2(-1),
	_t_actuator_controls_3(-1),
	_t_actuator_armed(-1),
	_t_vehicle_control_mode(-1),
	_t_param(-1),
	_t_vehicle_command(-1),
	_to_input_rc(0),
	_to_outputs(0),
	_to_battery(0),
	_to_servorail(0),
	_to_safety(0),
	_outputs{},
	_servorail_status{},
	_primary_pwm_device(false),
	_lockdown_override(false),
	_battery_amp_per_volt(90.0f / 5.0f), // this matches the 3DR current sensor
	_battery_amp_bias(0),
	_battery_mamphour_total(0),
	_battery_last_timestamp(0),
	_cb_flighttermination(true)
#ifdef CONFIG_ARCH_BOARD_PX4FMU_V1
	, _dsm_vcc_ctl(false)
#endif

{
	/* we need this potentially before it could be set in task_main */
	g_dev = this;

	_debug_enabled = false;
	_servorail_status.rssi_v = 0;
}

PX4IO::~PX4IO()
{
	/* tell the task we want it to go away */
	_task_should_exit = true;

	/* spin waiting for the task to stop */
	for (unsigned i = 0; (i < 10) && (_task != -1); i++) {
		/* give it another 100ms */
		usleep(100000);
	}

	/* well, kill it anyway, though this will probably crash */
	if (_task != -1)
		task_delete(_task);

	if (_interface != nullptr)
		delete _interface;

	/* deallocate perfs */
	perf_free(_perf_update);
	perf_free(_perf_write);
	perf_free(_perf_chan_count);

	g_dev = nullptr;
}

int
PX4IO::detect()
{
	int ret;

	if (_task == -1) {

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

		if (ret != OK)
			return ret;

		/* get some parameters */
		unsigned protocol = io_reg_get(PX4IO_PAGE_CONFIG, PX4IO_P_CONFIG_PROTOCOL_VERSION);

		if (protocol != PX4IO_PROTOCOL_VERSION) {
			if (protocol == _io_reg_get_error) {
				log("IO not installed");

			} else {
				log("IO version error");
				mavlink_log_emergency(_mavlink_fd, "IO VERSION MISMATCH, PLEASE UPGRADE SOFTWARE!");
			}

			return -1;
		}
	}

	log("IO found");

	return 0;
}

int
PX4IO::init(bool rc_handling_disabled) {
	_rc_handling_disabled = rc_handling_disabled;
	return init();
}

int
PX4IO::init()
{
	int ret;
	param_t sys_restart_param;
	int sys_restart_val = DM_INIT_REASON_VOLATILE;

	ASSERT(_task == -1);

	sys_restart_param = param_find("SYS_RESTART_TYPE");
	if (sys_restart_param != PARAM_INVALID) {
		/* Indicate restart type is unknown */
		param_set(sys_restart_param, &sys_restart_val);
	}

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

	if (ret != OK)
		return ret;

	/* get some parameters */
	unsigned protocol = io_reg_get(PX4IO_PAGE_CONFIG, PX4IO_P_CONFIG_PROTOCOL_VERSION);

	if (protocol == _io_reg_get_error) {
		log("failed to communicate with IO");
		mavlink_log_emergency(_mavlink_fd, "[IO] failed to communicate with IO, abort.");
		return -1;
	}

	if (protocol != PX4IO_PROTOCOL_VERSION) {
		log("protocol/firmware mismatch");
		mavlink_log_emergency(_mavlink_fd, "[IO] protocol/firmware mismatch, abort.");
		return -1;
	}

	_hardware      = io_reg_get(PX4IO_PAGE_CONFIG, PX4IO_P_CONFIG_HARDWARE_VERSION);
	_max_actuators = io_reg_get(PX4IO_PAGE_CONFIG, PX4IO_P_CONFIG_ACTUATOR_COUNT);
	_max_controls  = io_reg_get(PX4IO_PAGE_CONFIG, PX4IO_P_CONFIG_CONTROL_COUNT);
	_max_relays    = io_reg_get(PX4IO_PAGE_CONFIG, PX4IO_P_CONFIG_RELAY_COUNT);
	_max_transfer  = io_reg_get(PX4IO_PAGE_CONFIG, PX4IO_P_CONFIG_MAX_TRANSFER) - 2;
	_max_rc_input  = io_reg_get(PX4IO_PAGE_CONFIG, PX4IO_P_CONFIG_RC_INPUT_COUNT);

	if ((_max_actuators < 1) || (_max_actuators > 255) ||
	    (_max_relays > 32)   ||
	    (_max_transfer < 16) || (_max_transfer > 255)  ||
	    (_max_rc_input < 1)  || (_max_rc_input > 255)) {

		log("config read error");
		mavlink_log_emergency(_mavlink_fd, "[IO] config read fail, abort.");
		return -1;
	}

	if (_max_rc_input > RC_INPUT_MAX_CHANNELS)
		_max_rc_input = RC_INPUT_MAX_CHANNELS;

	/*
	 * Check for IO flight state - if FMU was flagged to be in
	 * armed state, FMU is recovering from an in-air reset.
	 * Read back status and request the commander to arm
	 * in this case.
	 */

	uint16_t reg;

	/* get IO's last seen FMU state */
	ret = io_reg_get(PX4IO_PAGE_SETUP, PX4IO_P_SETUP_ARMING, &reg, sizeof(reg));

	if (ret != OK)
		return ret;

	/*
	 * in-air restart is only tried if the IO board reports it is
	 * already armed, and has been configured for in-air restart
	 */
	if ((reg & PX4IO_P_SETUP_ARMING_INAIR_RESTART_OK) &&
	    (reg & PX4IO_P_SETUP_ARMING_FMU_ARMED)) {

		/* get a status update from IO */
		io_get_status();

		mavlink_log_emergency(_mavlink_fd, "[IO] RECOVERING FROM FMU IN-AIR RESTART");
		log("INAIR RESTART RECOVERY (needs commander app running)");

		/* WARNING: COMMANDER app/vehicle status must be initialized.
		 * If this fails (or the app is not started), worst-case IO
		 * remains untouched (so manual override is still available).
		 */

		int safety_sub = orb_subscribe(ORB_ID(actuator_armed));
		/* fill with initial values, clear updated flag */
		struct actuator_armed_s safety;
		uint64_t try_start_time = hrt_absolute_time();
		bool updated = false;

		/* keep checking for an update, ensure we got a arming information,
		   not something that was published a long time ago. */
		do {
			orb_check(safety_sub, &updated);

			if (updated) {
				/* got data, copy and exit loop */
				orb_copy(ORB_ID(actuator_armed), safety_sub, &safety);
				break;
			}

			/* wait 10 ms */
			usleep(10000);

			/* abort after 5s */
			if ((hrt_absolute_time() - try_start_time) / 1000 > 3000) {
				log("failed to recover from in-air restart (1), aborting IO driver init.");
				return 1;
			}

		} while (true);

		/* send command to arm system via command API */
		vehicle_command_s cmd;
		/* send this to itself */
		param_t sys_id_param = param_find("MAV_SYS_ID");
		param_t comp_id_param = param_find("MAV_COMP_ID");

		int32_t sys_id;
		int32_t comp_id;

		if (param_get(sys_id_param, &sys_id)) {
			errx(1, "PRM SYSID");
		}

		if (param_get(comp_id_param, &comp_id)) {
			errx(1, "PRM CMPID");
		}

		cmd.target_system = sys_id;
		cmd.target_component = comp_id;
		cmd.source_system = sys_id;
		cmd.source_component = comp_id;
		/* request arming */
		cmd.param1 = 1.0f;
		cmd.param2 = 0;
		cmd.param3 = 0;
		cmd.param4 = 0;
		cmd.param5 = 0;
		cmd.param6 = 0;
		cmd.param7 = 0;
		cmd.command = VEHICLE_CMD_COMPONENT_ARM_DISARM;

		/* ask to confirm command */
		cmd.confirmation =  1;

		/* send command once */
		orb_advert_t pub = orb_advertise(ORB_ID(vehicle_command), &cmd);

		/* spin here until IO's state has propagated into the system */
		do {
			orb_check(safety_sub, &updated);

			if (updated) {
				orb_copy(ORB_ID(actuator_armed), safety_sub, &safety);
			}

			/* wait 50 ms */
			usleep(50000);

			/* abort after 5s */
			if ((hrt_absolute_time() - try_start_time) / 1000 > 2000) {
				log("failed to recover from in-air restart (2), aborting IO driver init.");
				return 1;
			}

			/* re-send if necessary */
			if (!safety.armed) {
				orb_publish(ORB_ID(vehicle_command), pub, &cmd);
				log("re-sending arm cmd");
			}

			/* keep waiting for state change for 2 s */
		} while (!safety.armed);

		/* Indicate restart type is in-flight */
		sys_restart_val = DM_INIT_REASON_IN_FLIGHT;
		param_set(sys_restart_param, &sys_restart_val);


		/* regular boot, no in-air restart, init IO */

	} else {

		/* dis-arm IO before touching anything */
		io_reg_modify(PX4IO_PAGE_SETUP, PX4IO_P_SETUP_ARMING,
			      PX4IO_P_SETUP_ARMING_FMU_ARMED |
			      PX4IO_P_SETUP_ARMING_INAIR_RESTART_OK |
			      PX4IO_P_SETUP_ARMING_MANUAL_OVERRIDE_OK |
			      PX4IO_P_SETUP_ARMING_ALWAYS_PWM_ENABLE, 0);

		if (_rc_handling_disabled) {
			ret = io_disable_rc_handling();

			if (ret != OK) {
				log("failed disabling RC handling");
				return ret;
			}

		} else {
			/* publish RC config to IO */
			ret = io_set_rc_config();

			if (ret != OK) {
				log("failed to update RC input config");
				mavlink_log_info(_mavlink_fd, "[IO] RC config upload fail");
				return ret;
			}
		}

		/* Indicate restart type is power on */
		sys_restart_val = DM_INIT_REASON_POWER_ON;
		param_set(sys_restart_param, &sys_restart_val);

	}

	/* 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;
	}

	/* start the IO interface task */
	_task = task_spawn_cmd("px4io",
					SCHED_DEFAULT,
					SCHED_PRIORITY_ACTUATOR_OUTPUTS,
					2000,
					(main_t)&PX4IO::task_main_trampoline,
					nullptr);

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

	mavlink_log_info(_mavlink_fd, "[IO] init ok");

	return OK;
}

void
PX4IO::task_main_trampoline(int argc, char *argv[])
{
	g_dev->task_main();
}

void
PX4IO::task_main()
{
	hrt_abstime poll_last = 0;
	hrt_abstime orb_check_last = 0;

	_mavlink_fd = ::open(MAVLINK_LOG_DEVICE, 0);

	/*
	 * Subscribe to the appropriate PWM output topic based on whether we are the
	 * primary PWM output or not.
	 */
	_t_actuator_controls_0 = orb_subscribe(ORB_ID(actuator_controls_0));
	orb_set_interval(_t_actuator_controls_0, 20);		/* default to 50Hz */
	_t_actuator_controls_1 = orb_subscribe(ORB_ID(actuator_controls_1));
	orb_set_interval(_t_actuator_controls_1, 33);		/* default to 30Hz */
	_t_actuator_controls_2 = orb_subscribe(ORB_ID(actuator_controls_2));
	orb_set_interval(_t_actuator_controls_2, 33);		/* default to 30Hz */
	_t_actuator_controls_3 = orb_subscribe(ORB_ID(actuator_controls_3));
	orb_set_interval(_t_actuator_controls_3, 33);		/* default to 30Hz */
	_t_actuator_armed = orb_subscribe(ORB_ID(actuator_armed));
	_t_vehicle_control_mode = orb_subscribe(ORB_ID(vehicle_control_mode));
	_t_param = orb_subscribe(ORB_ID(parameter_update));
	_t_vehicle_command = orb_subscribe(ORB_ID(vehicle_command));

	if ((_t_actuator_controls_0 < 0) ||
	    (_t_actuator_armed < 0) ||
	    (_t_vehicle_control_mode < 0) ||
	    (_t_param < 0) ||
	    (_t_vehicle_command < 0)) {
		log("subscription(s) failed");
		goto out;
	}

	/* poll descriptor */
	pollfd fds[1];
	fds[0].fd = _t_actuator_controls_0;
	fds[0].events = POLLIN;

	/* lock against the ioctl handler */
	lock();

	/* loop talking to IO */
	while (!_task_should_exit) {

		/* adjust update interval */
		if (_update_interval != 0) {
			if (_update_interval < UPDATE_INTERVAL_MIN)
				_update_interval = UPDATE_INTERVAL_MIN;

			if (_update_interval > 100)
				_update_interval = 100;

			orb_set_interval(_t_actuator_controls_0, _update_interval);
			/*
			 * NOT changing the rate of groups 1-3 here, because only attitude
			 * really needs to run fast.
			 */
			_update_interval = 0;
		}

		/* sleep waiting for topic updates, but no more than 20ms */
		unlock();
		int ret = ::poll(fds, 1, 20);
		lock();

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

		perf_begin(_perf_update);
		hrt_abstime now = hrt_absolute_time();

		/* if we have new control data from the ORB, handle it */
		if (fds[0].revents & POLLIN) {

			/* we're not nice to the lower-priority control groups and only check them
			   when the primary group updated (which is now). */
			(void)io_set_control_groups();
		}

		if (now >= poll_last + IO_POLL_INTERVAL) {
			/* run at 50Hz */
			poll_last = now;

			/* pull status and alarms from IO */
			io_get_status();

			/* get raw R/C input from IO */
			io_publish_raw_rc();

			/* fetch PWM outputs from IO */
			io_publish_pwm_outputs();
		}

		if (now >= orb_check_last + ORB_CHECK_INTERVAL) {
			/* run at 5Hz */
			orb_check_last = now;

			/* try to claim the MAVLink log FD */
			if (_mavlink_fd < 0)
				_mavlink_fd = ::open(MAVLINK_LOG_DEVICE, 0);

			/* check updates on uORB topics and handle it */
			bool updated = false;

			/* arming state */
			orb_check(_t_actuator_armed, &updated);

			if (!updated) {
				orb_check(_t_vehicle_control_mode, &updated);
			}

			if (updated) {
				io_set_arming_state();
			}

			/* vehicle command */
			orb_check(_t_vehicle_command, &updated);

			if (updated) {
				struct vehicle_command_s cmd;
				orb_copy(ORB_ID(vehicle_command), _t_vehicle_command, &cmd);