add parameter to mavlink app to allow parsing of HIL GPS message even if not in HIL mode

Conflicts:
	src/modules/mavlink/mavlink_receiver.cpp

src/modules/mavlink/mavlink.c

@@ -62,6 +62,12 @@ PARAM_DEFINE_INT32(MAV_COMP_ID, 50);
  * @group MAVLink
  */
 PARAM_DEFINE_INT32(MAV_TYPE, MAV_TYPE_FIXED_WING);
+/**
+ * Use/Accept HIL GPS message (even if not in HIL mode)
+ * If set to 1 incomming HIL GPS messages are parsed.
+ * @group MAVLink
+ */
+PARAM_DEFINE_INT32(MAV_USEHILGPS, 0);
 
 mavlink_system_t mavlink_system = {
 	100,

src/modules/mavlink/mavlink_main.cpp

@@ -208,6 +208,7 @@ Mavlink::Mavlink() :
 	_mavlink_fd(-1),
 	_task_running(false),
 	_hil_enabled(false),
+	_use_hil_gps(false),
 	_is_usb_uart(false),
 	_wait_to_transmit(false),
 	_received_messages(false),
@@ -487,11 +488,13 @@ void Mavlink::mavlink_update_system(void)
 	static param_t param_system_id;
 	static param_t param_component_id;
 	static param_t param_system_type;
+	static param_t param_use_hil_gps;
 
 	if (!initialized) {
 		param_system_id = param_find("MAV_SYS_ID");
 		param_component_id = param_find("MAV_COMP_ID");
 		param_system_type = param_find("MAV_TYPE");
+		param_use_hil_gps = param_find("MAV_USEHILGPS");
 		initialized = true;
 	}
 
@@ -516,6 +519,11 @@ void Mavlink::mavlink_update_system(void)
 	if (system_type >= 0 && system_type < MAV_TYPE_ENUM_END) {
 		mavlink_system.type = system_type;
 	}
+
+	int32_t use_hil_gps;
+	param_get(param_use_hil_gps, &use_hil_gps);
+
+	_use_hil_gps = (bool)use_hil_gps;
 }
 
 int Mavlink::mavlink_open_uart(int baud, const char *uart_name, struct termios *uart_config_original, bool *is_usb)

src/modules/mavlink/mavlink_main.h

@@ -157,6 +157,8 @@ public:
 
 	bool		get_hil_enabled() { return _hil_enabled; }
 
+	bool		get_use_hil_gps() { return _use_hil_gps; }
+
 	bool		get_flow_control_enabled() { return _flow_control_enabled; }
 
 	bool		get_forwarding_on() { return _forwarding_on; }
@@ -223,6 +225,7 @@ private:
 
 	/* states */
 	bool		_hil_enabled;		/**< Hardware In the Loop mode */
+	bool		_use_hil_gps;		/**< Accept GPS HIL messages (for example from an external motion capturing system to fake indoor gps) */
 	bool		_is_usb_uart;		/**< Port is USB */
 	bool        _wait_to_transmit;  /**< Wait to transmit until received messages. */
 	bool        _received_messages; /**< Whether we've received valid mavlink messages. */

src/modules/mavlink/mavlink_receiver.cpp

@@ -162,6 +162,9 @@ MavlinkReceiver::handle_message(mavlink_message_t *msg)
 	 * The HIL mode is enabled by the HIL bit flag
 	 * in the system mode. Either send a set mode
 	 * COMMAND_LONG message or a SET_MODE message
+	 *
+	 * Accept HIL GPS messages if use_hil_gps flag is true.
+	 * This allows to provide fake gps measurements to the system.
 	 */
 	if (_mavlink->get_hil_enabled()) {
 		switch (msg->msgid) {
@@ -169,10 +172,6 @@ MavlinkReceiver::handle_message(mavlink_message_t *msg)
 			handle_message_hil_sensor(msg);
 			break;
 
-		case MAVLINK_MSG_ID_HIL_GPS:
-			handle_message_hil_gps(msg);
-			break;
-
 		case MAVLINK_MSG_ID_HIL_STATE_QUATERNION:
 			handle_message_hil_state_quaternion(msg);
 			break;
@@ -182,6 +181,19 @@ MavlinkReceiver::handle_message(mavlink_message_t *msg)
 		}
 	}
 
+
+	if (_mavlink->get_hil_enabled() || _mavlink->get_use_hil_gps()) {
+		switch (msg->msgid) {
+		case MAVLINK_MSG_ID_HIL_GPS:
+			handle_message_hil_gps(msg);
+			break;
+
+		default:
+			break;
+		}
+
+	}
+	
     /* If we've received a valid message, mark the flag indicating so.
 	   This is used in the '-w' command-line flag. */
 	_mavlink->set_has_received_messages(true);