diff --git a/libraries/AP_HAL_ChibiOS/UARTDriver.cpp b/libraries/AP_HAL_ChibiOS/UARTDriver.cpp
index ba47a65ad4..fe0b8f0e09 100644
--- a/libraries/AP_HAL_ChibiOS/UARTDriver.cpp
+++ b/libraries/AP_HAL_ChibiOS/UARTDriver.cpp
@@ -634,7 +634,7 @@ void UARTDriver::flush()
         sduSOFHookI((SerialUSBDriver*)sdef.serial);
 #endif
     } else {
-        //TODO: Handle this for other serial ports
+        chEvtSignal(uart_thread_ctx, EVT_TRANSMIT_DATA_READY);
     }
 }