mag.cpp

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

#include "mag.hpp"

#include <drivers/drv_hrt.h>
#include <systemlib/err.h>

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

UavcanMagnetometerBridge::UavcanMagnetometerBridge(uavcan::INode &node) :
    UavcanCDevSensorBridgeBase("uavcan_mag", "/dev/uavcan/mag", MAG_BASE_DEVICE_PATH, ORB_ID(sensor_mag)),
    _sub_mag(node),
    _sub_mag2(node)
{
    _device_id.devid_s.devtype = DRV_MAG_DEVTYPE_HMC5883;     // <-- Why?

    _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) {
        PX4_ERR("failed to start uavcan sub: %d", res);
        return res;
    }

    res = _sub_mag2.start(Mag2CbBinder(this, &UavcanMagnetometerBridge::mag2_sub_cb));

    if (res < 0) {
        PX4_ERR("failed to start uavcan sub2: %d", res);
        return res;
    }

    return 0;
}

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

    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 MAGIOCGEXTERNAL: {
            return 1;           // declare it external rise it's priority and to allow for correct orientation compensation
        }

    case MAGIOCCALIBRATE:
    case MAGIOCSRANGE:
    case MAGIOCEXSTRAP: {
            return -EINVAL;
        }

    default: {
            return CDev::ioctl(filp, cmd, arg);
        }
    }
}

void
UavcanMagnetometerBridge::mag_sub_cb(const uavcan::ReceivedDataStructure<uavcan::equipment::ahrs::MagneticFieldStrength>
                     &msg)
{
    lock();
    /*
     * FIXME HACK
     * This code used to rely on msg.getMonotonicTimestamp().toUSec() instead of HRT.
     * It stopped working when the time sync feature has been introduced, because it caused libuavcan
     * to use an independent time source (based on hardware TIM5) instead of HRT.
     * The proper solution is to be developed.
     */
    _report.timestamp = hrt_absolute_time();
    _report.device_id = _device_id.devid;
    _report.is_external = true;

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

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

void
UavcanMagnetometerBridge::mag2_sub_cb(const
                      uavcan::ReceivedDataStructure<uavcan::equipment::ahrs::MagneticFieldStrength2> &msg)
{
    lock();
    /*
     * FIXME HACK
     * This code used to rely on msg.getMonotonicTimestamp().toUSec() instead of HRT.
     * It stopped working when the time sync feature has been introduced, because it caused libuavcan
     * to use an independent time source (based on hardware TIM5) instead of HRT.
     * The proper solution is to be developed.
     */
    _report.timestamp = hrt_absolute_time();
    _report.device_id = _device_id.devid;
    _report.is_external = true;

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

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