diff --git a/backends/qualcomm/utils/utils.py b/backends/qualcomm/utils/utils.py
index 298664e2c96..88a84f2f9a6 100644
--- a/backends/qualcomm/utils/utils.py
+++ b/backends/qualcomm/utils/utils.py
@@ -7,7 +7,7 @@
 import operator
 import warnings
 from collections import OrderedDict
-from typing import Callable, Dict, List, Set, Tuple
+from typing import Callable, Dict, FrozenSet, List, Set, Tuple
 
 import executorch.backends.qualcomm.python.PyQnnManagerAdaptor as PyQnnManagerAdaptor
 
@@ -291,9 +291,8 @@ def get_decomp_table() -> Dict[torch._ops.OperatorBase, Callable]:
 
 
 def _transform(
-    edge_program: ExportedProgram, custom_pass_config: Set[str] = None
-) -> None:
-    custom_pass_config = custom_pass_config or {}
+    edge_program: ExportedProgram, custom_pass_config: FrozenSet[str] = frozenset()
+) -> ExportedProgram:
     # currently ExirExportedProgram.transform does not accept
     # changes of input number which was caused by FoldQDQ
     # apply passes one by one here to avoid IR capture failure
@@ -325,6 +324,7 @@ def _transform(
         edge_program.graph_module,
     )
     edge_program._validate()
+    return edge_program
 
 
 def capture_program(
diff --git a/examples/qualcomm/utils.py b/examples/qualcomm/utils.py
index 27c9db2ffcc..06225be2d1c 100755
--- a/examples/qualcomm/utils.py
+++ b/examples/qualcomm/utils.py
@@ -234,7 +234,7 @@ def build_executorch_binary(
     shared_buffer=False,
     metadata=None,
     dump_intermediate_outputs=False,
-    custom_pass_config=None,
+    custom_pass_config=frozenset(),
 ):
     if quant_dtype is not None:
         quantizer = custom_quantizer or make_quantizer(quant_dtype=quant_dtype)