Plane: use has_valid_input in place of checking throttle counter

ArduPlane/control_modes.cpp

@@ -107,9 +107,8 @@ void Plane::read_control_switch()
     // If we get this value we do not want to change modes.
     if(switchPosition == 255) return;
 
-    if (failsafe.rc_failsafe || failsafe.throttle_counter > 0) {
+    if (!rc().has_valid_input()) {
-        // when we are in rc_failsafe mode then RC input is not
+        // ignore the mode switch channel if there is no valid RC input
-        // working, and we need to ignore the mode switch channel
         return;
     }
 

ArduPlane/quadplane.cpp

@@ -1224,7 +1224,8 @@ float QuadPlane::get_desired_yaw_rate_cds(bool should_weathervane)
 // get pilot desired climb rate in cm/s
 float QuadPlane::get_pilot_desired_climb_rate_cms(void) const
 {
-    if (plane.failsafe.rc_failsafe || plane.failsafe.throttle_counter > 0) {
+    if (!rc().has_valid_input()) {
+        // no valid input means no sensible pilot desired climb rate.
         // descend at 0.5m/s for now
         return -50;
     }
@@ -1735,8 +1736,7 @@ void QuadPlane::update(void)
     // disable throttle_wait when throttle rises above 10%
     if (throttle_wait &&
         (plane.get_throttle_input() > 10 ||
-         plane.failsafe.rc_failsafe ||
+         !rc().has_valid_input())) {
-         plane.failsafe.throttle_counter>0)) {
         throttle_wait = false;
     }
 

ArduPlane/servos.cpp

@@ -561,7 +561,7 @@ void Plane::set_servos_controlled(void)
                control_mode == &mode_fbwa ||
                control_mode == &mode_autotune) {
         // a manual throttle mode
-        if (failsafe.throttle_counter) {
+        if (!rc().has_valid_input()) {
             SRV_Channels::set_output_scaled(SRV_Channel::k_throttle, 0.0);
         } else if (g.throttle_passthru_stabilize) {
             // manual pass through of throttle while in FBWA or
@@ -615,7 +615,7 @@ void Plane::set_servos_flaps(void)
     int8_t manual_flap_percent = 0;
 
     // work out any manual flap input
-    if (channel_flap != nullptr && !failsafe.rc_failsafe && failsafe.throttle_counter == 0) {
+    if (channel_flap != nullptr && rc().has_valid_input()) {
         manual_flap_percent = channel_flap->percent_input();
     }