2 files changed, 32 insertions, 3 deletions

diff --git a/shared-bindings/microcontroller/Pin.c b/shared-bindings/microcontroller/Pin.c
index 3635f0afb..67aecaf66 100644
--- a/shared-bindings/microcontroller/Pin.c
+++ b/shared-bindings/microcontroller/Pin.c
@@ -84,10 +84,35 @@ const mp_obj_type_t mcu_pin_type = {
     .print = mcu_pin_print
 };
 
-void assert_pin(mp_obj_t obj, bool none_ok) {
-    if ((obj != mp_const_none || !none_ok) && !MP_OBJ_IS_TYPE(obj, &mcu_pin_type)) {
+mcu_pin_obj_t *validate_obj_is_pin(mp_obj_t obj) {
+    if (!MP_OBJ_IS_TYPE(obj, &mcu_pin_type)) {
         mp_raise_TypeError_varg(translate("Expected a %q"), mcu_pin_type.name);
     }
+    return MP_OBJ_TO_PTR(obj);
+}
+
+// Validate that the obj is a pin or None. Return an mcu_pin_obj_t* or NULL, correspondingly.
+mcu_pin_obj_t *validate_obj_is_pin_or_none(mp_obj_t obj) {
+    if (obj == mp_const_none) {
+        return NULL;
+    }
+    return validate_obj_is_pin(obj);
+}
+
+mcu_pin_obj_t *validate_obj_is_free_pin(mp_obj_t obj) {
+    mcu_pin_obj_t *pin = validate_obj_is_pin(obj);
+    assert_pin_free(pin);
+    return pin;
+}
+
+// Validate that the obj is a free pin or None. Return an mcu_pin_obj_t* or NULL, correspondingly.
+mcu_pin_obj_t *validate_obj_is_free_pin_or_none(mp_obj_t obj) {
+    if (obj == mp_const_none) {
+        return NULL;
+    }
+    mcu_pin_obj_t *pin = validate_obj_is_pin(obj);
+    assert_pin_free(pin);
+    return pin;
 }
 
 void assert_pin_free(const mcu_pin_obj_t* pin) {
diff --git a/shared-bindings/microcontroller/Pin.h b/shared-bindings/microcontroller/Pin.h
index 2d15dd5c5..4f29322a0 100644
--- a/shared-bindings/microcontroller/Pin.h
+++ b/shared-bindings/microcontroller/Pin.h
@@ -33,7 +33,11 @@
 // Type object used in Python. Should be shared between ports.
 extern const mp_obj_type_t mcu_pin_type;
 
-void assert_pin(mp_obj_t obj, bool none_ok);
+mcu_pin_obj_t *validate_obj_is_pin(mp_obj_t obj);
+mcu_pin_obj_t *validate_obj_is_pin_or_none(mp_obj_t obj);
+mcu_pin_obj_t *validate_obj_is_free_pin(mp_obj_t obj);
+mcu_pin_obj_t *validate_obj_is_free_pin_or_none(mp_obj_t obj);
+
 void assert_pin_free(const mcu_pin_obj_t* pin);
 
 bool common_hal_mcu_pin_is_free(const mcu_pin_obj_t* pin);