path: root/src/modules/uavcan/sensors/mag.cpp

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/**
 * @author Pavel Kirienko <pavel.kirienko@gmail.com>
 */

#include "mag.hpp"

#include <systemlib/err.h>

static const orb_id_t MAG_TOPICS[3] = {
	ORB_ID(sensor_mag0),
	ORB_ID(sensor_mag1),
	ORB_ID(sensor_mag2)
};

const char *const UavcanMagnetometerBridge::NAME = "mag";

UavcanMagnetometerBridge::UavcanMagnetometerBridge(uavcan::INode& node) :
UavcanCDevSensorBridgeBase("uavcan_mag", "/dev/uavcan/mag", MAG_DEVICE_PATH, MAG_TOPICS),
_sub_mag(node)
{
	_device_id.devid_s.devtype = DRV_MAG_DEVTYPE_HMC5883;

	_scale.x_scale = 1.0F;
	_scale.y_scale = 1.0F;
	_scale.z_scale = 1.0F;
}

int UavcanMagnetometerBridge::init()
{
	int res = device::CDev::init();
	if (res < 0) {
		return res;
	}

	res = _sub_mag.start(MagCbBinder(this, &UavcanMagnetometerBridge::mag_sub_cb));
	if (res < 0) {
		log("failed to start uavcan sub: %d", res);
		return res;
	}
	return 0;
}

ssize_t UavcanMagnetometerBridge::read(struct file *filp, char *buffer, size_t buflen)
{
	static uint64_t last_read = 0;
	struct mag_report *mag_buf = reinterpret_cast<struct mag_report *>(buffer);

	/* buffer must be large enough */
	unsigned count = buflen / sizeof(struct mag_report);
	if (count < 1) {
		return -ENOSPC;
	}

	if (last_read < _report.timestamp) {
		/* copy report */
		lock();
		*mag_buf = _report;
		last_read = _report.timestamp;
		unlock();
		return sizeof(struct mag_report);
	} else {
		/* no new data available, warn caller */
		return -EAGAIN;
	}
}

int UavcanMagnetometerBridge::ioctl(struct file *filp, int cmd, unsigned long arg)
{
	switch (cmd) {
	case SENSORIOCSQUEUEDEPTH: {
		return OK;			// Pretend that this stuff is supported to keep APM happy
	}
	case MAGIOCSSCALE: {
		std::memcpy(&_scale, reinterpret_cast<const void*>(arg), sizeof(_scale));
		return 0;
	}
	case MAGIOCGSCALE: {
		std::memcpy(reinterpret_cast<void*>(arg), &_scale, sizeof(_scale));
		return 0;
	}
	case MAGIOCSELFTEST: {
		return 0;           // Nothing to do
	}
	case MAGIOCGEXTERNAL: {
		return 1;           // declare it external rise it's priority and to allow for correct orientation compensation
	}
	case MAGIOCSSAMPLERATE: {
		return 0;           // Pretend that this stuff is supported to keep the sensor app happy
	}
	case MAGIOCCALIBRATE:
	case MAGIOCGSAMPLERATE:
	case MAGIOCSRANGE:
	case MAGIOCGRANGE:
	case MAGIOCSLOWPASS:
	case MAGIOCEXSTRAP:
	case MAGIOCGLOWPASS: {
		return -EINVAL;
	}
	default: {
		return CDev::ioctl(filp, cmd, arg);
	}
	}
}

void UavcanMagnetometerBridge::mag_sub_cb(const uavcan::ReceivedDataStructure<uavcan::equipment::ahrs::Magnetometer> &msg)
{
	lock();
	_report.range_ga = 1.3F;   // Arbitrary number, doesn't really mean anything
	_report.timestamp = msg.getMonotonicTimestamp().toUSec();

	_report.x = (msg.magnetic_field[0] - _scale.x_offset) * _scale.x_scale;
	_report.y = (msg.magnetic_field[1] - _scale.y_offset) * _scale.y_scale;
	_report.z = (msg.magnetic_field[2] - _scale.z_offset) * _scale.z_scale;
	unlock();

	publish(msg.getSrcNodeID().get(), &_report);
}