ACPICA: Refactor evaluate_object to reduce nesting

ACPICA commit 599e9159f53565e4a3f3e67f6a03f81fcb10a4cf

Original patch from hanjun.guo@linaro.org

ACPICA BZ 1072.

Link: https://github.com/acpica/acpica/commit/599e9159
Link: https://bugs.acpica.org/show_bug.cgi?id=1072
Original-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 55 insertions, 56 deletions

diff --git a/drivers/acpi/acpica/nsxfeval.c b/drivers/acpi/acpica/nsxfeval.c
index 614e4baacaf4..d2a9b4fd739f 100644
--- a/drivers/acpi/acpica/nsxfeval.c
+++ b/drivers/acpi/acpica/nsxfeval.c
@@ -280,13 +280,12 @@ acpi_evaluate_object(acpi_handle handle,
                 info->parameters[info->param_count] = NULL;
         }
 
-#if 0
+#ifdef _FUTURE_FEATURE
 
         /*
          * Begin incoming argument count analysis. Check for too few args
          * and too many args.
          */
-
         switch (acpi_ns_get_type(info->node)) {
         case ACPI_TYPE_METHOD:
 
@@ -370,68 +369,68 @@ acpi_evaluate_object(acpi_handle handle,
          * If we are expecting a return value, and all went well above,
          * copy the return value to an external object.
          */
-        if (return_buffer) {
-                if (!info->return_object) {
-                        return_buffer->length = 0;
-                } else {
-                        if (ACPI_GET_DESCRIPTOR_TYPE(info->return_object) ==
-                            ACPI_DESC_TYPE_NAMED) {
-                                /*
-                                 * If we received a NS Node as a return object, this means that
-                                 * the object we are evaluating has nothing interesting to
-                                 * return (such as a mutex, etc.)  We return an error because
-                                 * these types are essentially unsupported by this interface.
-                                 * We don't check up front because this makes it easier to add
-                                 * support for various types at a later date if necessary.
-                                 */
-                                status = AE_TYPE;
-                                info->return_object = NULL;     /* No need to delete a NS Node */
-                                return_buffer->length = 0;
-                        }
+        if (!return_buffer) {
+                goto cleanup_return_object;
+        }
 
-                        if (ACPI_SUCCESS(status)) {
+        if (!info->return_object) {
+                return_buffer->length = 0;
+                goto cleanup;
+        }
 
-                                /* Dereference Index and ref_of references */
+        if (ACPI_GET_DESCRIPTOR_TYPE(info->return_object) ==
+            ACPI_DESC_TYPE_NAMED) {
+                /*
+                 * If we received a NS Node as a return object, this means that
+                 * the object we are evaluating has nothing interesting to
+                 * return (such as a mutex, etc.)  We return an error because
+                 * these types are essentially unsupported by this interface.
+                 * We don't check up front because this makes it easier to add
+                 * support for various types at a later date if necessary.
+                 */
+                status = AE_TYPE;
+                info->return_object = NULL;     /* No need to delete a NS Node */
+                return_buffer->length = 0;
+        }
 
-                                acpi_ns_resolve_references(info);
+        if (ACPI_FAILURE(status)) {
+                goto cleanup_return_object;
+        }
 
-                                /* Get the size of the returned object */
+        /* Dereference Index and ref_of references */
 
-                                status =
-                                    acpi_ut_get_object_size(info->return_object,
-                                                            &buffer_space_needed);
-                                if (ACPI_SUCCESS(status)) {
-
-                                        /* Validate/Allocate/Clear caller buffer */
-
-                                        status =
-                                            acpi_ut_initialize_buffer
-                                            (return_buffer,
-                                             buffer_space_needed);
-                                        if (ACPI_FAILURE(status)) {
-                                                /*
-                                                 * Caller's buffer is too small or a new one can't
-                                                 * be allocated
-                                                 */
-                                                ACPI_DEBUG_PRINT((ACPI_DB_INFO,
-                                                                  "Needed buffer size %X, %s\n",
-                                                                  (u32)
-                                                                  buffer_space_needed,
-                                                                  acpi_format_exception
-                                                                  (status)));
-                                        } else {
-                                                /* We have enough space for the object, build it */
-
-                                                status =
-                                                    acpi_ut_copy_iobject_to_eobject
-                                                    (info->return_object,
-                                                     return_buffer);
-                                        }
-                                }
-                        }
+        acpi_ns_resolve_references(info);
+
+        /* Get the size of the returned object */
+
+        status = acpi_ut_get_object_size(info->return_object,
+                                         &buffer_space_needed);
+        if (ACPI_SUCCESS(status)) {
+
+                /* Validate/Allocate/Clear caller buffer */
+
+                status = acpi_ut_initialize_buffer(return_buffer,
+                                                   buffer_space_needed);
+                if (ACPI_FAILURE(status)) {
+                        /*
+                         * Caller's buffer is too small or a new one can't
+                         * be allocated
+                         */
+                        ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+                                          "Needed buffer size %X, %s\n",
+                                          (u32)buffer_space_needed,
+                                          acpi_format_exception(status)));
+                } else {
+                        /* We have enough space for the object, build it */
+
+                        status =
+                            acpi_ut_copy_iobject_to_eobject(info->return_object,
+                                                            return_buffer);
                 }
         }
 
+cleanup_return_object:
+
         if (info->return_object) {
                 /*
                  * Delete the internal return object. NOTE: Interpreter must be