Commander: cleanup COM_POSCTL_NAVL parameter

- move to px4::params
- use enum

src/modules/commander/Commander.cpp

@@ -1243,9 +1243,6 @@ Commander::run()
 	param_t _param_airmode = param_find("MC_AIRMODE");
 	param_t _param_rc_map_arm_switch = param_find("RC_MAP_ARM_SW");
 
-	/* failsafe response to loss of navigation accuracy */
-	param_t _param_posctl_nav_loss_act = param_find("COM_POSCTL_NAVL");
-
 	status_flags.avoidance_system_required = _param_com_obs_avoid.get();
 
 	/* pthread for slow low prio thread */
@@ -1374,7 +1371,6 @@ Commander::run()
 	param_get(_param_rc_arm_hyst, &rc_arm_hyst);
 	rc_arm_hyst *= COMMANDER_MONITORING_LOOPSPERMSEC;
 
-	int32_t posctl_nav_loss_act = 0;
 	int32_t geofence_action = 0;
 	int32_t flight_uuid = 0;
 	int32_t airmode = 0;
@@ -1508,9 +1504,6 @@ Commander::run()
 			param_get(_param_fmode_5, &_flight_mode_slots[4]);
 			param_get(_param_fmode_6, &_flight_mode_slots[5]);
 
-			/* failsafe response to loss of navigation accuracy */
-			param_get(_param_posctl_nav_loss_act, &posctl_nav_loss_act);
-
 			param_get(_param_takeoff_finished_action, &takeoff_complete_act);
 
 			/* check for unsafe Airmode settings: yaw airmode requires the use of an arming switch */
@@ -2317,7 +2310,7 @@ Commander::run()
 						       (link_loss_actions_t)_param_nav_rcl_act.get(),
 						       _param_com_obl_act.get(),
 						       _param_com_obl_rc_act.get(),
-						       posctl_nav_loss_act);
+						       (position_nav_loss_actions_t)_param_com_posctl_navl.get());
 
 		if (status.failsafe != failsafe_old) {
 			status_changed = true;

src/modules/commander/Commander.hpp

@@ -116,6 +116,7 @@ private:
 		(ParamFloat<px4::params::COM_POS_FS_EPH>) _param_com_pos_fs_eph,
 		(ParamFloat<px4::params::COM_POS_FS_EPV>) _param_com_pos_fs_epv,
 		(ParamFloat<px4::params::COM_VEL_FS_EVH>) _param_com_vel_fs_evh,
+		(ParamInt<px4::params::COM_POSCTL_NAVL>) _param_com_posctl_navl,	/* failsafe response to loss of navigation accuracy */
 
 		(ParamInt<px4::params::COM_POS_FS_DELAY>) _param_com_pos_fs_delay,
 		(ParamInt<px4::params::COM_POS_FS_PROB>) _param_com_pos_fs_prob,

src/modules/commander/commander_params.c

@@ -649,8 +649,8 @@ PARAM_DEFINE_INT32(COM_ARM_MIS_REQ, 0);
  * This sets the flight mode that will be used if navigation accuracy is no longer adequate for position control.
  * Navigation accuracy checks can be disabled using the CBRK_VELPOSERR parameter, but doing so will remove protection for all flight modes.
  *
- * @value 0 Assume use of remote control after fallback. Switch to Altitude mode if a height estimate is available, else switch to MANUAL.
- * @value 1 Assume no use of remote control after fallback. Switch to Land mode if a height estimate is available, else switch to TERMINATION.
+ * @value 0 Altitude/Manual. Assume use of remote control after fallback. Switch to Altitude mode if a height estimate is available, else switch to MANUAL.
+ * @value 1 Land/Terminate.  Assume no use of remote control after fallback. Switch to Land mode if a height estimate is available, else switch to TERMINATION.
  *
  * @group Commander
  */

src/modules/commander/state_machine_helper.cpp

@@ -393,7 +393,7 @@ bool set_nav_state(vehicle_status_s *status, actuator_armed_s *armed, commander_
 		   orb_advert_t *mavlink_log_pub, const link_loss_actions_t data_link_loss_act, const bool mission_finished,
 		   const bool stay_in_failsafe, const vehicle_status_flags_s &status_flags, bool landed,
 		   const link_loss_actions_t rc_loss_act, const int offb_loss_act, const int offb_loss_rc_act,
-		   const int posctl_nav_loss_act)
+		   const position_nav_loss_actions_t posctl_nav_loss_act)
 {
 	navigation_state_t nav_state_old = status->nav_state;
 
@@ -468,7 +468,8 @@ bool set_nav_state(vehicle_status_s *status, actuator_armed_s *armed, commander_
 				 * For fixedwing, a global position is needed. */
 
 			} else if (is_armed
-				   && check_invalid_pos_nav_state(status, old_failsafe, mavlink_log_pub, status_flags, !(posctl_nav_loss_act == 1),
+				   && check_invalid_pos_nav_state(status, old_failsafe, mavlink_log_pub, status_flags,
+						   !(posctl_nav_loss_act == position_nav_loss_actions_t::LAND_TERMINATE),
 						   status->vehicle_type == vehicle_status_s::VEHICLE_TYPE_FIXED_WING)) {
 				// nothing to do - everything done in check_invalid_pos_nav_state
 

src/modules/commander/state_machine_helper.h

@@ -68,6 +68,11 @@ enum class link_loss_actions_t {
 	LOCKDOWN = 6,		// Kill the motors, same result as kill switch
 };
 
+enum class position_nav_loss_actions_t {
+	ALTITUDE_MANUAL = 0,	// Altitude/Manual. Assume use of remote control after fallback. Switch to Altitude mode if a height estimate is available, else switch to MANUAL.
+	LAND_TERMINATE = 1,	// Land/Terminate.  Assume no use of remote control after fallback. Switch to Land mode if a height estimate is available, else switch to TERMINATION.
+};
+
 typedef enum {
 	ARM_REQ_NONE = 0,
 	ARM_REQ_MISSION_BIT = (1 << 0),
@@ -95,7 +100,7 @@ bool set_nav_state(vehicle_status_s *status, actuator_armed_s *armed, commander_
 		   orb_advert_t *mavlink_log_pub, const link_loss_actions_t data_link_loss_act, const bool mission_finished,
 		   const bool stay_in_failsafe, const vehicle_status_flags_s &status_flags, bool landed,
 		   const link_loss_actions_t rc_loss_act, const int offb_loss_act, const int offb_loss_rc_act,
-		   const int posctl_nav_loss_act);
+		   const position_nav_loss_actions_t posctl_nav_loss_act);
 
 /*
  * Checks the validty of position data aaainst the requirements of the current navigation