/****************************************************************************
 *
 *   Copyright (C) 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 lsm303d.cpp
 * Driver for the ST LSM303D MEMS accel / mag connected via SPI.
 */

#include <nuttx/config.h>

#include <sys/types.h>
#include <stdint.h>
#include <stdbool.h>
#include <stddef.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 <systemlib/perf_counter.h>
#include <systemlib/err.h>

#include <nuttx/arch.h>
#include <nuttx/clock.h>

#include <drivers/drv_hrt.h>
#include <arch/board/board.h>

#include <drivers/device/spi.h>
#include <drivers/drv_accel.h>
#include <drivers/drv_mag.h>


/* oddly, ERROR is not defined for c++ */
#ifdef ERROR
# undef ERROR
#endif
static const int ERROR = -1;

/* SPI protocol address bits */
#define DIR_READ				(1<<7)
#define DIR_WRITE				(0<<7)
#define ADDR_INCREMENT				(1<<6)

/* register addresses */
#define ADDR_TEMP_OUT_L         0x05
#define ADDR_TEMP_OUT_H         0x06
#define ADDR_STATUS_M           0x07
#define ADDR_OUT_X_L_M          0x08
#define ADDR_OUT_X_H_M          0x09
#define ADDR_OUT_Y_L_M          0x08
#define ADDR_OUT_Y_H_M          0x09
#define ADDR_OUT_Z_L_M          0x0A
#define ADDR_OUT_Z_H_M          0x0B

#define ADDR_WHO_AM_I			0x0F
#define WHO_I_AM				0x49

#define INT_CTRL_M              0x12
#define INT_SRC_M               0x13

extern "C" { __EXPORT int lsm303d_main(int argc, char *argv[]); }

class LSM303D : public device::SPI
{
public:
	LSM303D(int bus, const char* path, spi_dev_e device);
	virtual ~LSM303D();

	virtual int		init();

	virtual ssize_t		read(struct file *filp, char *buffer, size_t buflen);
	virtual int		ioctl(struct file *filp, int cmd, unsigned long arg);

	/**
	 * Diagnostics - print some basic information about the driver.
	 */
	void			print_info();

protected:
	virtual int		probe();

private:

	struct hrt_call		_call;
	unsigned		_call_interval;

	unsigned		_num_reports;
	volatile unsigned	_next_report;
	volatile unsigned	_oldest_report;
	struct gyro_report	*_reports;

	struct gyro_scale	_gyro_scale;
	float			_gyro_range_scale;
	float			_gyro_range_rad_s;
	orb_advert_t		_gyro_topic;

	unsigned		_current_rate;
	unsigned		_current_range;

	perf_counter_t		_sample_perf;

	/**
	 * Start automatic measurement.
	 */
	void			start();

	/**
	 * Stop automatic measurement.
	 */
	void			stop();

	/**
	 * Static trampoline from the hrt_call context; because we don't have a
	 * generic hrt wrapper yet.
	 *
	 * Called by the HRT in interrupt context at the specified rate if
	 * automatic polling is enabled.
	 *
	 * @param arg		Instance pointer for the driver that is polling.
	 */
	static void		measure_trampoline(void *arg);

	/**
	 * Fetch measurements from the sensor and update the report ring.
	 */
	void			measure();

	/**
	 * Read a register from the LSM303D
	 *
	 * @param		The register to read.
	 * @return		The value that was read.
	 */
	uint8_t			read_reg(unsigned reg);

	/**
	 * Write a register in the LSM303D
	 *
	 * @param reg		The register to write.
	 * @param value		The new value to write.
	 */
	void			write_reg(unsigned reg, uint8_t value);

	/**
	 * Modify a register in the LSM303D
	 *
	 * Bits are cleared before bits are set.
	 *
	 * @param reg		The register to modify.
	 * @param clearbits	Bits in the register to clear.
	 * @param setbits	Bits in the register to set.
	 */
	void			modify_reg(unsigned reg, uint8_t clearbits, uint8_t setbits);

	/**
	 * Set the LSM303D measurement range.
	 *
	 * @param max_dps	The measurement range is set to permit reading at least
	 *			this rate in degrees per second.
	 *			Zero selects the maximum supported range.
	 * @return		OK if the value can be supported, -ERANGE otherwise.
	 */
	int			set_range(unsigned max_dps);

	/**
	 * Set the LSM303D internal sampling frequency.
	 *
	 * @param frequency	The internal sampling frequency is set to not less than
	 *			this value.
	 *			Zero selects the maximum rate supported.
	 * @return		OK if the value can be supported.
	 */
	int			set_samplerate(unsigned frequency);
};

/* helper macro for handling report buffer indices */
#define INCREMENT(_x, _lim)	do { _x++; if (_x >= _lim) _x = 0; } while(0)


LSM303D::LSM303D(int bus, const char* path, spi_dev_e device) :
	SPI("LSM303D", path, bus, device, SPIDEV_MODE3, 8000000),
	_call_interval(0),
	_num_reports(0),
	_next_report(0),
	_oldest_report(0),
	_reports(nullptr),
	_gyro_range_scale(0.0f),
	_gyro_range_rad_s(0.0f),
	_gyro_topic(-1),
	_current_rate(0),
	_current_range(0),
	_sample_perf(perf_alloc(PC_ELAPSED, "lsm303d_read"))
{
	// enable debug() calls
	_debug_enabled = true;

	// default scale factors
	_gyro_scale.x_offset = 0;
	_gyro_scale.x_scale  = 1.0f;
	_gyro_scale.y_offset = 0;
	_gyro_scale.y_scale  = 1.0f;
	_gyro_scale.z_offset = 0;
	_gyro_scale.z_scale  = 1.0f;
}

LSM303D::~LSM303D()
{
	/* make sure we are truly inactive */
	stop();

	/* free any existing reports */
	if (_reports != nullptr)
		delete[] _reports;

	/* delete the perf counter */
	perf_free(_sample_perf);
}

int
LSM303D::init()
{
	int ret = ERROR;

	/* do SPI init (and probe) first */
	if (SPI::init() != OK)
		goto out;

	/* allocate basic report buffers */
	_num_reports = 2;
	_oldest_report = _next_report = 0;
	_reports = new struct accel_report[_num_reports];

	if (_reports == nullptr)
		goto out;

	/* advertise sensor topic */
	memset(&_reports[0], 0, sizeof(_reports[0]));
	_accel_topic = orb_advertise(ORB_ID(sensor_accel), &_reports[0]);

//	/* set default configuration */
//	write_reg(ADDR_CTRL_REG1, REG1_POWER_NORMAL | REG1_Z_ENABLE | REG1_Y_ENABLE | REG1_X_ENABLE);
//	write_reg(ADDR_CTRL_REG2, 0);		/* disable high-pass filters */
//	write_reg(ADDR_CTRL_REG3, 0);		/* no interrupts - we don't use them */
//	write_reg(ADDR_CTRL_REG4, REG4_BDU);
//	write_reg(ADDR_CTRL_REG5, 0);
//
//	write_reg(ADDR_CTRL_REG5, REG5_FIFO_ENABLE);	  /* disable wake-on-interrupt */
//	write_reg(ADDR_FIFO_CTRL_REG, FIFO_CTRL_STREAM_MODE); /* Enable FIFO, old data is overwritten */

	set_range(500);				/* default to 500dps */
	set_samplerate(0);			/* max sample rate */

	ret = OK;
out:
	return ret;
}

int
LSM303D::probe()
{
	/* read dummy value to void to clear SPI statemachine on sensor */
	(void)read_reg(ADDR_WHO_AM_I);

	/* verify that the device is attached and functioning */
	if (read_reg(ADDR_WHO_AM_I) == WHO_I_AM)
		return OK;

	return -EIO;
}

ssize_t
LSM303D::read(struct file *filp, char *buffer, size_t buflen)
{
	unsigned count = buflen / sizeof(struct gyro_report);
	int ret = 0;

//	/* buffer must be large enough */
//	if (count < 1)
//		return -ENOSPC;
//
//	/* if automatic measurement is enabled */
//	if (_call_interval > 0) {
//
//		/*
//		 * While there is space in the caller's buffer, and reports, copy them.
//		 * Note that we may be pre-empted by the measurement code while we are doing this;
//		 * we are careful to avoid racing with it.
//		 */
//		while (count--) {
//			if (_oldest_report != _next_report) {
//				memcpy(buffer, _reports + _oldest_report, sizeof(*_reports));
//				ret += sizeof(_reports[0]);
//				INCREMENT(_oldest_report, _num_reports);
//			}
//		}
//
//		/* if there was no data, warn the caller */
//		return ret ? ret : -EAGAIN;
//	}
//
//	/* manual measurement */
//	_oldest_report = _next_report = 0;
//	measure();
//
//	/* measurement will have generated a report, copy it out */
//	memcpy(buffer, _reports, sizeof(*_reports));
//	ret = sizeof(*_reports);

	return ret;
}

int
LSM303D::ioctl(struct file *filp, int cmd, unsigned long arg)
{
	switch (cmd) {

//	case SENSORIOCSPOLLRATE: {
//			switch (arg) {
//
//				/* switching to manual polling */
//			case SENSOR_POLLRATE_MANUAL:
//				stop();
//				_call_interval = 0;
//				return OK;
//
//				/* external signalling not supported */
//			case SENSOR_POLLRATE_EXTERNAL:
//
//				/* zero would be bad */
//			case 0:
//				return -EINVAL;
//
//				/* set default/max polling rate */
//			case SENSOR_POLLRATE_MAX:
//			case SENSOR_POLLRATE_DEFAULT:
//				/* With internal low pass filters enabled, 250 Hz is sufficient */
//				return ioctl(filp, SENSORIOCSPOLLRATE, 250);
//
//				/* adjust to a legal polling interval in Hz */
//			default: {
//					/* do we need to start internal polling? */
//					bool want_start = (_call_interval == 0);
//
//					/* convert hz to hrt interval via microseconds */
//					unsigned ticks = 1000000 / arg;
//
//					/* check against maximum sane rate */
//					if (ticks < 1000)
//						return -EINVAL;
//
//					/* update interval for next measurement */
//					/* XXX this is a bit shady, but no other way to adjust... */
//					_call.period = _call_interval = ticks;
//
//					/* if we need to start the poll state machine, do it */
//					if (want_start)
//						start();
//
//					return OK;
//				}
//			}
//		}
//
//	case SENSORIOCGPOLLRATE:
//		if (_call_interval == 0)
//			return SENSOR_POLLRATE_MANUAL;
//
//		return 1000000 / _call_interval;
//
//	case SENSORIOCSQUEUEDEPTH: {
//			/* account for sentinel in the ring */
//			arg++;
//
//			/* lower bound is mandatory, upper bound is a sanity check */
//			if ((arg < 2) || (arg > 100))
//				return -EINVAL;
//
//			/* allocate new buffer */
//			struct gyro_report *buf = new struct gyro_report[arg];
//
//			if (nullptr == buf)
//				return -ENOMEM;
//
//			/* reset the measurement state machine with the new buffer, free the old */
//			stop();
//			delete[] _reports;
//			_num_reports = arg;
//			_reports = buf;
//			start();
//
//			return OK;
//		}
//
//	case SENSORIOCGQUEUEDEPTH:
//		return _num_reports - 1;
//
//	case SENSORIOCRESET:
//		/* XXX implement */
//		return -EINVAL;
//
//	case GYROIOCSSAMPLERATE:
//		return set_samplerate(arg);
//
//	case GYROIOCGSAMPLERATE:
//		return _current_rate;
//
//	case GYROIOCSLOWPASS:
//	case GYROIOCGLOWPASS:
//		/* XXX not implemented due to wacky interaction with samplerate */
//		return -EINVAL;
//
//	case GYROIOCSSCALE:
//		/* copy scale in */
//		memcpy(&_gyro_scale, (struct gyro_scale *) arg, sizeof(_gyro_scale));
//		return OK;
//
//	case GYROIOCGSCALE:
//		/* copy scale out */
//		memcpy((struct gyro_scale *) arg, &_gyro_scale, sizeof(_gyro_scale));
//		return OK;
//
//	case GYROIOCSRANGE:
//		return set_range(arg);
//
//	case GYROIOCGRANGE:
//		return _current_range;

	default:
		/* give it to the superclass */
		return SPI::ioctl(filp, cmd, arg);
	}
}

uint8_t
LSM303D::read_reg(unsigned reg)
{
	uint8_t cmd[2];

	cmd[0] = reg | DIR_READ;

	transfer(cmd, cmd, sizeof(cmd));

	return cmd[1];
}

void
LSM303D::write_reg(unsigned reg, uint8_t value)
{
	uint8_t	cmd[2];

	cmd[0] = reg | DIR_WRITE;
	cmd[1] = value;

	transfer(cmd, nullptr, sizeof(cmd));
}

void
LSM303D::modify_reg(unsigned reg, uint8_t clearbits, uint8_t setbits)
{
	uint8_t	val;

	val = read_reg(reg);
	val &= ~clearbits;
	val |= setbits;
	write_reg(reg, val);
}

int
LSM303D::set_range(unsigned max_dps)
{
//	uint8_t bits = REG4_BDU;
//
//	if (max_dps == 0)
//		max_dps = 2000;
//
//	if (max_dps <= 250) {
//		_current_range = 250;
//		bits |= RANGE_250DPS;
//
//	} else if (max_dps <= 500) {
//		_current_range = 500;
//		bits |= RANGE_500DPS;
//
//	} else if (max_dps <= 2000) {
//		_current_range = 2000;
//		bits |= RANGE_2000DPS;
//
//	} else {
//		return -EINVAL;
//	}
//
//	_gyro_range_rad_s = _current_range / 180.0f * M_PI_F;
//	_gyro_range_scale = _gyro_range_rad_s / 32768.0f;
//	write_reg(ADDR_CTRL_REG4, bits);

	return OK;
}

int
LSM303D::set_samplerate(unsigned frequency)
{
//	uint8_t bits = REG1_POWER_NORMAL | REG1_Z_ENABLE | REG1_Y_ENABLE | REG1_X_ENABLE;
//
//	if (frequency == 0)
//		frequency = 760;
//
//	if (frequency <= 95) {
//		_current_rate = 95;
//		bits |= RATE_95HZ_LP_25HZ;
//
//	} else if (frequency <= 190) {
//		_current_rate = 190;
//		bits |= RATE_190HZ_LP_25HZ;
//
//	} else if (frequency <= 380) {
//		_current_rate = 380;
//		bits |= RATE_380HZ_LP_30HZ;
//
//	} else if (frequency <= 760) {
//		_current_rate = 760;
//		bits |= RATE_760HZ_LP_30HZ;
//
//	} else {
//		return -EINVAL;
//	}
//
//	write_reg(ADDR_CTRL_REG1, bits);

	return OK;
}

void
LSM303D::start()
{
	/* make sure we are stopped first */
	stop();

	/* reset the report ring */
	_oldest_report = _next_report = 0;

	/* start polling at the specified rate */
	hrt_call_every(&_call, 1000, _call_interval, (hrt_callout)&LSM303D::measure_trampoline, this);
}

void
LSM303D::stop()
{
	hrt_cancel(&_call);
}

void
LSM303D::measure_trampoline(void *arg)
{
	LSM303D *dev = (LSM303D *)arg;

	/* make another measurement */
	dev->measure();
}

void
LSM303D::measure()
{
//	/* status register and data as read back from the device */
//#pragma pack(push, 1)
//	struct {
//		uint8_t		cmd;
//		uint8_t		temp;
//		uint8_t		status;
//		int16_t		x;
//		int16_t		y;
//		int16_t		z;
//	} raw_report;
//#pragma pack(pop)
//
//	gyro_report		*report = &_reports[_next_report];
//
//	/* start the performance counter */
//	perf_begin(_sample_perf);
//
//	/* fetch data from the sensor */
//	raw_report.cmd = ADDR_OUT_TEMP | DIR_READ | ADDR_INCREMENT;
//	transfer((uint8_t *)&raw_report, (uint8_t *)&raw_report, sizeof(raw_report));
//
//	/*
//	 * 1) Scale raw value to SI units using scaling from datasheet.
//	 * 2) Subtract static offset (in SI units)
//	 * 3) Scale the statically calibrated values with a linear
//	 *    dynamically obtained factor
//	 *
//	 * Note: the static sensor offset is the number the sensor outputs
//	 * 	 at a nominally 'zero' input. Therefore the offset has to
//	 * 	 be subtracted.
//	 *
//	 *	 Example: A gyro outputs a value of 74 at zero angular rate
//	 *	 	  the offset is 74 from the origin and subtracting
//	 *		  74 from all measurements centers them around zero.
//	 */
//	report->timestamp = hrt_absolute_time();
//	/* XXX adjust for sensor alignment to board here */
//	report->x_raw = raw_report.x;
//	report->y_raw = raw_report.y;
//	report->z_raw = raw_report.z;
//
//	report->x = ((report->x_raw * _gyro_range_scale) - _gyro_scale.x_offset) * _gyro_scale.x_scale;
//	report->y = ((report->y_raw * _gyro_range_scale) - _gyro_scale.y_offset) * _gyro_scale.y_scale;
//	report->z = ((report->z_raw * _gyro_range_scale) - _gyro_scale.z_offset) * _gyro_scale.z_scale;
//	report->scaling = _gyro_range_scale;
//	report->range_rad_s = _gyro_range_rad_s;
//
//	/* post a report to the ring - note, not locked */
//	INCREMENT(_next_report, _num_reports);
//
//	/* if we are running up against the oldest report, fix it */
//	if (_next_report == _oldest_report)
//		INCREMENT(_oldest_report, _num_reports);
//
//	/* notify anyone waiting for data */
//	poll_notify(POLLIN);
//
//	/* publish for subscribers */
//	orb_publish(ORB_ID(sensor_gyro), _gyro_topic, report);

	/* stop the perf counter */
	perf_end(_sample_perf);
}

void
LSM303D::print_info()
{
	perf_print_counter(_sample_perf);
	printf("report queue:   %u (%u/%u @ %p)\n",
	       _num_reports, _oldest_report, _next_report, _reports);
}

/**
 * Local functions in support of the shell command.
 */
namespace lsm303d
{

LSM303D	*g_dev;

void	start();
void	test();
void	reset();
void	info();

/**
 * Start the driver.
 */
void
start()
{
	int fd;

	if (g_dev != nullptr)
		errx(1, "already started");

	/* create the driver */
	g_dev = new LSM303D(1 /* XXX magic number */, ACCEL_DEVICE_PATH, (spi_dev_e)PX4_SPIDEV_ACCEL);

	if (g_dev == nullptr)
		goto fail;

	if (OK != g_dev->init())
		goto fail;

	/* set the poll rate to default, starts automatic data collection */
	fd = open(ACCEL_DEVICE_PATH, O_RDONLY);

	if (fd < 0)
		goto fail;

	if (ioctl(fd, SENSORIOCSPOLLRATE, SENSOR_POLLRATE_DEFAULT) < 0)
		goto fail;

	exit(0);
fail:

	if (g_dev != nullptr) {
		delete g_dev;
		g_dev = nullptr;
	}

	errx(1, "driver start failed");
}

/**
 * Perform some basic functional tests on the driver;
 * make sure we can collect data from the sensor in polled
 * and automatic modes.
 */
void
test()
{
	int fd_accel = -1;
	struct accel_report a_report;
	ssize_t sz;

	/* get the driver */
	fd_accel = open(ACCEL_DEVICE_PATH, O_RDONLY);

	if (fd_accel < 0)
		err(1, "%s open failed", ACCEL_DEVICE_PATH);

	/* reset to manual polling */
	if (ioctl(fd_accel, SENSORIOCSPOLLRATE, SENSOR_POLLRATE_MANUAL) < 0)
		err(1, "reset to manual polling");

	/* do a simple demand read */
	sz = read(fd_accel, &a_report, sizeof(a_report));

	if (sz != sizeof(a_report))
		err(1, "immediate gyro read failed");

	warnx("accel x: \t% 9.5f\tm/s^2", (double)a_report.x);
	warnx("accel y: \t% 9.5f\tm/s^2", (double)a_report.y);
	warnx("accel z: \t% 9.5f\tm/s^2", (double)a_report.z);
	warnx("accel x: \t%d\traw", (int)a_report.x_raw);
	warnx("accel y: \t%d\traw", (int)a_report.y_raw);
	warnx("accel z: \t%d\traw", (int)a_report.z_raw);
	warnx("accel range: %8.4f m/s^2", (double)a_report.range_m_s2);

	/* XXX add poll-rate tests here too */

	reset();
	errx(0, "PASS");
}

/**
 * Reset the driver.
 */
void
reset()
{
	int fd = open(ACCEL_DEVICE_PATH, O_RDONLY);

	if (fd < 0)
		err(1, "failed ");

	if (ioctl(fd, SENSORIOCRESET, 0) < 0)
		err(1, "driver reset failed");

	if (ioctl(fd, SENSORIOCSPOLLRATE, SENSOR_POLLRATE_DEFAULT) < 0)
		err(1, "driver poll restart failed");

	exit(0);
}

/**
 * Print a little info about the driver.
 */
void
info()
{
	if (g_dev == nullptr)
		errx(1, "driver not running\n");

	printf("state @ %p\n", g_dev);
	g_dev->print_info();

	exit(0);
}


} // namespace

int
lsm303d_main(int argc, char *argv[])
{
	/*
	 * Start/load the driver.

	 */
	if (!strcmp(argv[1], "start"))
		LSM303D::start();

	/*
	 * Test the driver/device.
	 */
	if (!strcmp(argv[1], "test"))
		lsm303d::test();

	/*
	 * Reset the driver.
	 */
	if (!strcmp(argv[1], "reset"))
		lsm303d::reset();

	/*
	 * Print driver information.
	 */
	if (!strcmp(argv[1], "info"))
		lsm303d::info();

	errx(1, "unrecognized command, try 'start', 'test', 'reset' or 'info'");
}