diff --git a/libraries/AP_HAL_ChibiOS/RCInput.cpp b/libraries/AP_HAL_ChibiOS/RCInput.cpp
index 2c7bbdfc525..6d60cf33909 100644
--- a/libraries/AP_HAL_ChibiOS/RCInput.cpp
+++ b/libraries/AP_HAL_ChibiOS/RCInput.cpp
@@ -116,6 +116,14 @@ uint8_t RCInput::read(uint16_t* periods, uint8_t len)
     return len;
 }
 
+// there is no point enabling the thread if you're not using the
+// RCProtocol library - this catches regressions in our hwdefs.  It
+// can be removed in the future when the chance of there being
+// outstanding work with regressions in is negigible
+#if HAL_RCIN_THREAD_ENABLED && !AP_RCPROTOCOL_ENABLED
+#error Do not enable the RCIN thread when not doing AP_RCPROTOCOL_ENABLED
+#endif
+
 void RCInput::_timer_tick(void)
 {
     if (!_init) {
diff --git a/libraries/AP_HAL_ChibiOS/Scheduler.cpp b/libraries/AP_HAL_ChibiOS/Scheduler.cpp
index 85dbd07db9a..29b27179b9c 100644
--- a/libraries/AP_HAL_ChibiOS/Scheduler.cpp
+++ b/libraries/AP_HAL_ChibiOS/Scheduler.cpp
@@ -60,10 +60,6 @@ extern AP_IOMCU iomcu;
 
 using namespace ChibiOS;
 
-#ifndef HAL_RCIN_THREAD_ENABLED
-#define HAL_RCIN_THREAD_ENABLED 1
-#endif
-
 #ifndef HAL_MONITOR_THREAD_ENABLED
 #define HAL_MONITOR_THREAD_ENABLED 1
 #endif