ardupilot/libraries/AP_GPS/AP_GPS_UAVCAN.cpp

/*
 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation, either version 3 of the License, or
 (at your option) any later version.

 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.

 You should have received a copy of the GNU General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

//
//  UAVCAN GPS driver
//
#include "AP_GPS_UAVCAN.h"
#include <stdint.h>

#if HAL_WITH_UAVCAN
#include <AP_UAVCAN/AP_UAVCAN.h>
#include <AP_BoardConfig/AP_BoardConfig.h>
#include <AP_BoardConfig/AP_BoardConfig_CAN.h>

extern const AP_HAL::HAL& hal;

#define debug_gps_uavcan(level, fmt, args...) do { if ((level) <= AP_BoardConfig_CAN::get_can_debug()) { printf(fmt, ##args); }} while (0)

AP_GPS_UAVCAN::AP_GPS_UAVCAN(AP_GPS &_gps, AP_GPS::GPS_State &_state, AP_HAL::UARTDriver *_port) :
    AP_GPS_Backend(_gps, _state, _port)
{
    _new_data = false;
    _sem_gnss = hal.util->new_semaphore();
}

// For each instance we need to deregister from AP_UAVCAN class
AP_GPS_UAVCAN::~AP_GPS_UAVCAN()
{
    if (hal.can_mgr[_manager] != nullptr) {
        AP_UAVCAN *ap_uavcan = hal.can_mgr[_manager]->get_UAVCAN();
        if (ap_uavcan != nullptr) {
            ap_uavcan->remove_gps_listener(this);

            debug_gps_uavcan(2, "AP_GPS_UAVCAN destructed\n\r");
        }
    }
}

void AP_GPS_UAVCAN::set_uavcan_manager(uint8_t mgr)
{
    _manager = mgr;
}

// Consume new data and mark it received
bool AP_GPS_UAVCAN::read(void)
{
    if (_sem_gnss->take(HAL_SEMAPHORE_BLOCK_FOREVER)) {
        if (_new_data) {
            _new_data = false;

            state = _interm_state;
            _sem_gnss->give();

            return true;
        }

        _sem_gnss->give();
    }
    return false;
}

void AP_GPS_UAVCAN::handle_gnss_msg(const AP_GPS::GPS_State &msg)
{
    if (_sem_gnss->take(HAL_SEMAPHORE_BLOCK_FOREVER)) {
        _interm_state = msg;
        _new_data = true;
        _sem_gnss->give();
    }
}

#endif // HAL_WITH_UAVCAN