ACPICA: Update behavior of CopyObject to match ACPI spec

Fixed a problem where a CopyObject to RegionField, BankField, and
IndexField objects did not perform an implicit conversion as it
should. These types must retain their initial type permanently as
per the ACPI specification. However, a CopyObject to all other
object types should not perform an implicit conversion, as per
the ACPI specification.

http://www.acpica.org/bugzilla/show_bug.cgi?id=388

Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 11 insertions, 4 deletions

diff --git a/drivers/acpi/executer/exstore.c b/drivers/acpi/executer/exstore.c
index 725614e277f8..36c0fccb137a 100644
--- a/drivers/acpi/executer/exstore.c
+++ b/drivers/acpi/executer/exstore.c
@@ -603,10 +603,17 @@ acpi_ex_store_object_to_node(union acpi_operand_object *source_desc,
 
         /* If no implicit conversion, drop into the default case below */
 
-        if ((!implicit_conversion) || (walk_state->opcode == AML_COPY_OP)) {
-
-                /* Force execution of default (no implicit conversion) */
-
+        if ((!implicit_conversion) ||
+            ((walk_state->opcode == AML_COPY_OP) &&
+             (target_type != ACPI_TYPE_LOCAL_REGION_FIELD) &&
+             (target_type != ACPI_TYPE_LOCAL_BANK_FIELD) &&
+             (target_type != ACPI_TYPE_LOCAL_INDEX_FIELD))) {
+                /*
+                 * Force execution of default (no implicit conversion). Note:
+                 * copy_object does not perform an implicit conversion, as per the ACPI
+                 * spec -- except in case of region/bank/index fields -- because these
+                 * objects must retain their original type permanently.
+                 */
                 target_type = ACPI_TYPE_ANY;
         }