GPS_Glitch: make enable/disable a parameter

libraries/AP_GPS/AP_GPS_Glitch.cpp

@@ -10,11 +10,24 @@
 
 extern const AP_HAL::HAL& hal;
 
+// table of user settable parameters
+const AP_Param::GroupInfo GPS_Glitch::var_info[] PROGMEM = {
+    // @Param: ENABLE
+    // @DisplayName: GPS Glitch protection enable/disable
+    // @Description: Allows you to enable (1) or disable (0) gps glitch protection
+    // @Values: 0:Disabled,1:Enabled
+    // @User: Standard
+    AP_GROUPINFO("ENABLE",      0,  GPS_Glitch,   _enabled,   1),
+
+    AP_GROUPEND
+};
+
 // constuctor
 GPS_Glitch::GPS_Glitch(GPS*& gps) :
     _gps(gps)
 {
-    _flags.enabled = true;
+    AP_Param::setup_object_defaults(this, var_info);
+    _enabled = true;
 }
 
 // check_position - returns true if gps position is acceptable, false if not
@@ -35,7 +48,7 @@ void GPS_Glitch::check_position()
     }
 
     // if not initialised or disabled update last good position and exit
-    if (!_flags.initialised || !_flags.enabled) {
+    if (!_flags.initialised || !_enabled) {
         _last_good_update = now;
         _last_good_lat = _gps->latitude;
         _last_good_lon = _gps->longitude;

libraries/AP_GPS/AP_GPS_Glitch.h

@@ -28,10 +28,10 @@ public:
     void    check_position();
 
     // enable - enable or disable gps sanity checking
-    void    enable(bool true_or_false) { _flags.enabled = true_or_false; }
+    void    enable(bool true_or_false) { _enabled = true_or_false; }
 
     // enabled - returns true if glitch detection is enabled
-    bool    enabled() { return _flags.enabled; }
+    bool    enabled() { return _enabled; }
 
     // glitching - returns true if we are experiencing a glitch
     bool    glitching() { return _flags.glitching; }
@@ -39,6 +39,9 @@ public:
     // last_good_update - returns system time of the last good update
     uint32_t last_good_update() { return _last_good_update; }
 
+    // class level parameters
+    static const struct AP_Param::GroupInfo var_info[];
+
 private:
 
     /// external dependencies
@@ -47,10 +50,12 @@ private:
     /// structure for holding flags
     struct GPS_Glitch_flags {
         uint8_t initialised : 1; // 1 if we have received at least one good gps lock
-        uint8_t enabled     : 1; // 1 if we are enabled
         uint8_t glitching   : 1; // 1 if we are experiencing a gps glitch
     } _flags;
 
+    // parameters
+    AP_Int8     _enabled;           // top level enable/disable control
+
     // gps sanity check variables
     uint32_t    _last_good_update;  // system time of last gps update that passed checks
     int32_t     _last_good_lat;     // last good latitude reported by the gps