Plane: add support for RCn_OPTION (servorelay,camera)

Closes #7071
Closes #7666

ArduPlane/ArduPlane.cpp

@@ -90,6 +90,7 @@ const AP_Scheduler::Task Plane::scheduler_tasks[] = {
 #endif
     SCHED_TASK_CLASS(AP_InertialSensor, &plane.ins, periodic, 50, 50),
     SCHED_TASK(avoidance_adsb_update,  10,    100),
+    SCHED_TASK(read_aux_all,           10,    200),
     SCHED_TASK_CLASS(AP_Button, &plane.g2.button, update, 5, 100),
 #if STATS_ENABLED == ENABLED
     SCHED_TASK_CLASS(AP_Stats, &plane.g2.stats, update, 1, 100),
@@ -130,6 +131,11 @@ void Plane::update_soft_armed()
     DataFlash.set_vehicle_armed(hal.util->get_soft_armed());
 }
 
+void Plane::read_aux_all()
+{
+    plane.g2.rc_channels.read_aux_all();
+}
+
 // update AHRS system
 void Plane::ahrs_update()
 {

ArduPlane/Plane.h

@@ -1033,6 +1033,8 @@ private:
     void update_soaring();
 #endif
 
+    void read_aux_all();
+
     // support for AP_Avoidance custom flight mode, AVOID_ADSB
     bool avoid_adsb_init(bool ignore_checks);
     void avoid_adsb_run();

ArduPlane/RC_Channel.cpp

@@ -15,3 +15,14 @@ int8_t RC_Channels_Plane::flight_mode_channel_number() const
 {
     return plane.g.flight_mode_channel.get();
 }
+
+bool RC_Channels_Plane::has_valid_input() const
+{
+    if (plane.failsafe.rc_failsafe) {
+        return false;
+    }
+    if (plane.failsafe.throttle_counter != 0) {
+        return false;
+    }
+    return true;
+}

ArduPlane/RC_Channel.h

@@ -25,6 +25,8 @@ public:
         return &obj_channels[chan];
     }
 
+    bool has_valid_input() const override;
+
 protected:
 
     // note that these callbacks are not presently used on Plane: