ACPICA: Fix for implicit return compatibility
authorLin Ming <ming.m.lin@intel.com>
Sat, 27 Sep 2008 04:01:12 +0000 (12:01 +0800)
committerLen Brown <len.brown@intel.com>
Thu, 23 Oct 2008 03:14:49 +0000 (23:14 -0400)
Predicate can be used for an implicit return value.
This change improves the implicit return mechanism to be more
compatible with the MS interpreter.

http://www.acpica.org/bugzilla/show_bug.cgi?id=349

Below AML code from http://bugzilla.kernel.org/show_bug.cgi?id=10686

Store(0x07D6, OSYS)
Method (_CRT, 0, Serialized)
{
    If (LLess (OSYS, 0x07D6))
    {
If (LEqual (\_SB.TJ85, Zero))
{
    Return (Add (0x0AAC, Multiply (TPC, 0x0A)))
}
Else
{
    Return (Add (0x0AAC, Multiply (TP85, 0x0A)))
}
    }
}

Previously _CRT returns 0x07D6, now it returns 0 (predicate value of LLess)

Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
drivers/acpi/dispatcher/dswexec.c

index 5b2419197b9b005c98883eb9d074fbbc5e0adb9f..396fe12078cd1595f99199c8bf837be59df7f3ae 100644 (file)
@@ -166,6 +166,10 @@ acpi_ds_get_predicate_value(struct acpi_walk_state *walk_state,
                status = AE_CTRL_FALSE;
        }
 
+       /* Predicate can be used for an implicit return value */
+
+       (void)acpi_ds_do_implicit_return(local_obj_desc, walk_state, TRUE);
+
       cleanup:
 
        ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Completed a predicate eval=%X Op=%p\n",