From c9c33fd7374e20c8ab0c219aee66e43569718fc9 Mon Sep 17 00:00:00 2001
From: Hans Christian Olaussen <41271048+klutvott123@users.noreply.github.com>
Date: Mon, 23 Dec 2019 11:05:11 +0100
Subject: [PATCH] LUA sport/crossfireTelemetryPush protocol detection (#7229)

Make sportTelemetryPush/crossfireTelemetryPush return nil if they detect the wrong telemetry protocol.
This allows us to differentiate between wrong protocol and telemetry buffer not available. For lua scripts supporting both crossfire and smartport this will let us reliably detect the telemetry protocol using these functions.
---
 radio/src/lua/api_general.cpp | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/radio/src/lua/api_general.cpp b/radio/src/lua/api_general.cpp
index b87d02fc2..2a5db1422 100644
--- a/radio/src/lua/api_general.cpp
+++ b/radio/src/lua/api_general.cpp
@@ -440,13 +440,15 @@ When called without parameters, it will only return the status of the output buf
 
 @retval boolean  data queued in output buffer or not.
 
-@status current Introduced in 2.2.0
+@retval nil      incorrect telemetry protocol.
+
+@status current Introduced in 2.2.0, retval nil added in 2.3.4
 */
 
 static int luaSportTelemetryPush(lua_State * L)
 {
   if (!IS_FRSKY_SPORT_PROTOCOL()) {
-    lua_pushboolean(L, false);
+    lua_pushnil(L);
     return 1;
   }
 
@@ -637,12 +639,14 @@ When called without parameters, it will only return the status of the output buf
 
 @retval boolean  data queued in output buffer or not.
 
-@status current Introduced in 2.2.0
+@retval nil      incorrect telemetry protocol.
+
+@status current Introduced in 2.2.0, retval nil added in 2.3.4
 */
 static int luaCrossfireTelemetryPush(lua_State * L)
 {
   if (telemetryProtocol != PROTOCOL_TELEMETRY_CROSSFIRE) {
-    lua_pushboolean(L, false);
+    lua_pushnil(L);
     return 1;
   }