diff --git a/tools/aconfig/src/codegen.rs b/tools/aconfig/src/codegen.rs
index e50be0b..fe52c8d 100644
--- a/tools/aconfig/src/codegen.rs
+++ b/tools/aconfig/src/codegen.rs
@@ -37,7 +37,7 @@
 
 pub fn create_device_config_ident(package: &str, flag_name: &str) -> Result<String> {
     ensure!(is_valid_package_ident(package), "bad package");
-    ensure!(is_valid_package_ident(flag_name), "bad flag name");
+    ensure!(is_valid_name_ident(flag_name), "bad flag name");
     Ok(format!("{}.{}", package, flag_name))
 }