3 files changed, 33 insertions, 17 deletions

diff --git a/source/components/namespace/nspredef.c b/source/components/namespace/nspredef.c
index 7122e7a..7b7e3e3 100644
--- a/source/components/namespace/nspredef.c
+++ b/source/components/namespace/nspredef.c
@@ -166,6 +166,16 @@ AcpiNsCheckReturnValue (
     }
 
     /*
+     *
+     * 4) If there is no return value and it is optional, just return
+     * AE_OK (_WAK).
+     */
+    if (!(*ReturnObjectPtr))
+    {
+        goto Exit;
+    }
+
+    /*
      * For returned Package objects, check the type of all sub-objects.
      * Note: Package may have been newly created by call above.
      */
@@ -293,7 +303,13 @@ TypeErrorExit:
 
     AcpiUtGetExpectedReturnTypes (TypeBuffer, ExpectedBtypes);
 
-    if (PackageIndex == ACPI_NOT_PACKAGE_ELEMENT)
+    if (!ReturnObject)
+    {
+        ACPI_WARN_PREDEFINED ((AE_INFO, Info->FullPathname, Info->NodeFlags,
+            "Expected return object of type %s",
+            TypeBuffer));
+    }
+    else if (PackageIndex == ACPI_NOT_PACKAGE_ELEMENT)
     {
         ACPI_WARN_PREDEFINED ((AE_INFO, Info->FullPathname, Info->NodeFlags,
             "Return type mismatch - found %s, expected %s",
diff --git a/source/components/namespace/nswalk.c b/source/components/namespace/nswalk.c
index 0b25ffd..577b89b 100644
--- a/source/components/namespace/nswalk.c
+++ b/source/components/namespace/nswalk.c
@@ -165,9 +165,9 @@ AcpiNsGetNextNodeTyped (
  *              MaxDepth            - Depth to which search is to reach
  *              Flags               - Whether to unlock the NS before invoking
  *                                    the callback routine
- *              PreOrderVisit       - Called during tree pre-order visit
+ *              DescendingCallback  - Called during tree descent
  *                                    when an object of "Type" is found
- *              PostOrderVisit      - Called during tree post-order visit
+ *              AscendingCallback   - Called during tree ascent
  *                                    when an object of "Type" is found
  *              Context             - Passed to user function(s) above
  *              ReturnValue         - from the UserFunction if terminated
@@ -195,8 +195,8 @@ AcpiNsWalkNamespace (
     ACPI_HANDLE             StartNode,
     UINT32                  MaxDepth,
     UINT32                  Flags,
-    ACPI_WALK_CALLBACK      PreOrderVisit,
-    ACPI_WALK_CALLBACK      PostOrderVisit,
+    ACPI_WALK_CALLBACK      DescendingCallback,
+    ACPI_WALK_CALLBACK      AscendingCallback,
     void                    *Context,
     void                    **ReturnValue)
 {
@@ -274,22 +274,22 @@ AcpiNsWalkNamespace (
             }
 
             /*
-             * Invoke the user function, either pre-order or post-order
+             * Invoke the user function, either descending, ascending,
              * or both.
              */
             if (!NodePreviouslyVisited)
             {
-                if (PreOrderVisit)
+                if (DescendingCallback)
                 {
-                    Status = PreOrderVisit (ChildNode, Level,
+                    Status = DescendingCallback (ChildNode, Level,
                                 Context, ReturnValue);
                 }
             }
             else
             {
-                if (PostOrderVisit)
+                if (AscendingCallback)
                 {
-                    Status = PostOrderVisit (ChildNode, Level,
+                    Status = AscendingCallback (ChildNode, Level,
                                 Context, ReturnValue);
                 }
             }
diff --git a/source/components/namespace/nsxfeval.c b/source/components/namespace/nsxfeval.c
index 6a2649a..e5c1e17 100644
--- a/source/components/namespace/nsxfeval.c
+++ b/source/components/namespace/nsxfeval.c
@@ -574,9 +574,9 @@ AcpiNsResolveReferences (
  * PARAMETERS:  Type                - ACPI_OBJECT_TYPE to search for
  *              StartObject         - Handle in namespace where search begins
  *              MaxDepth            - Depth to which search is to reach
- *              PreOrderVisit       - Called during tree pre-order visit
+ *              DescendingCallback  - Called during tree descent
  *                                    when an object of "Type" is found
- *              PostOrderVisit      - Called during tree post-order visit
+ *              AscendingCallback   - Called during tree ascent
  *                                    when an object of "Type" is found
  *              Context             - Passed to user function(s) above
  *              ReturnValue         - Location where return value of
@@ -605,8 +605,8 @@ AcpiWalkNamespace (
     ACPI_OBJECT_TYPE        Type,
     ACPI_HANDLE             StartObject,
     UINT32                  MaxDepth,
-    ACPI_WALK_CALLBACK      PreOrderVisit,
-    ACPI_WALK_CALLBACK      PostOrderVisit,
+    ACPI_WALK_CALLBACK      DescendingCallback,
+    ACPI_WALK_CALLBACK      AscendingCallback,
     void                    *Context,
     void                    **ReturnValue)
 {
@@ -620,7 +620,7 @@ AcpiWalkNamespace (
 
     if ((Type > ACPI_TYPE_LOCAL_MAX) ||
         (!MaxDepth)                  ||
-        (!PreOrderVisit && !PostOrderVisit))
+        (!DescendingCallback && !AscendingCallback))
     {
         return_ACPI_STATUS (AE_BAD_PARAMETER);
     }
@@ -655,8 +655,8 @@ AcpiWalkNamespace (
     }
 
     Status = AcpiNsWalkNamespace (Type, StartObject, MaxDepth,
-                ACPI_NS_WALK_UNLOCK, PreOrderVisit,
-                PostOrderVisit, Context, ReturnValue);
+                ACPI_NS_WALK_UNLOCK, DescendingCallback,
+                AscendingCallback, Context, ReturnValue);
 
     (void) AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);