add ws2812 4 channels for RGBW strips + diagnostic output (#3637)

Author: HHHartmann

app/lua/luac_cross/lflashimg.c

@@ -399,6 +399,7 @@ uint dumpToFlashImage (lua_State* L, const Proto *main, lua_Writer w,
 
   fh->flash_sig = FLASH_SIG + (address ? FLASH_SIG_ABSOLUTE : 0);
   fh->flash_size = curOffset*WORDSIZE;
+  printf("Image size: %d\n", fh->flash_size);
   if (fh->flash_size>maxSize) {
     fatal ("The image is too large for specfied LFS size");
   }

app/modules/ws2812.c

@@ -138,7 +138,7 @@ static int ws2812_write(lua_State* L) {
   else if (type == LUA_TUSERDATA)
   {
     pixbuf *buffer = pixbuf_from_lua_arg(L, 1);
-    luaL_argcheck(L, pixbuf_channels(buffer) == 3, 1, "Bad pixbuf format");
+    luaL_argcheck(L, pixbuf_channels(buffer) == 3 || pixbuf_channels(buffer) == 4, 1, "Bad pixbuf format");
     buffer1 = buffer->values;
     length1 = pixbuf_size(buffer);
   }
@@ -163,7 +163,7 @@ static int ws2812_write(lua_State* L) {
   else if (type == LUA_TUSERDATA)
   {
     pixbuf *buffer = pixbuf_from_lua_arg(L, 2);
-    luaL_argcheck(L, pixbuf_channels(buffer) == 3, 2, "Bad pixbuf format");
+    luaL_argcheck(L, pixbuf_channels(buffer) == 3 || pixbuf_channels(buffer) == 4, 2, "Bad pixbuf format");
     buffer2 = buffer->values;
     length2 = pixbuf_size(buffer);
   }