1 files changed, 6 insertions, 1 deletions
diff --git a/libvo/vo_png.c b/libvo/vo_png.c
index b211b60541..2ee152ef8a 100644
--- a/libvo/vo_png.c
+++ b/libvo/vo_png.c
@@ -327,7 +327,12 @@ static void check_events(void)
 
 static uint32_t preinit(const char *arg)
 {
-  return 0;
+    if(arg) 
+    {
+	printf("PNG Unknown subdevice: %s\n",arg);
+	return ENOSYS;
+    }
+    return 0;
 }
 
 static uint32_t control(uint32_t request, void *data, ...)