ACPICA: Add option to disable method return value validation and repair

Runtime option can be used to disable return value repair if this
is causing a problem on a particular machine.

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

2 files changed, 18 insertions, 6 deletions

diff --git a/drivers/acpi/acpica/acglobal.h b/drivers/acpi/acpica/acglobal.h
index 73863d86f022..76dc02f15574 100644
--- a/drivers/acpi/acpica/acglobal.h
+++ b/drivers/acpi/acpica/acglobal.h
@@ -126,6 +126,12 @@ u8 ACPI_INIT_GLOBAL(acpi_gbl_copy_dsdt_locally, FALSE);
  */
 u8 ACPI_INIT_GLOBAL(acpi_gbl_truncate_io_addresses, FALSE);
 
+/*
+ * Disable runtime checking and repair of values returned by control methods.
+ * Use only if the repair is causing a problem on a particular machine.
+ */
+u8 ACPI_INIT_GLOBAL(acpi_gbl_disable_auto_repair, FALSE);
+
 /* acpi_gbl_FADT is a local copy of the FADT, converted to a common format. */
 
 struct acpi_table_fadt acpi_gbl_FADT;
diff --git a/drivers/acpi/acpica/nspredef.c b/drivers/acpi/acpica/nspredef.c
index 9fb03fa8ffde..607a9a035262 100644
--- a/drivers/acpi/acpica/nspredef.c
+++ b/drivers/acpi/acpica/nspredef.c
@@ -193,14 +193,20 @@ acpi_ns_check_predefined_names(struct acpi_namespace_node *node,
         }
 
         /*
-         * 1) We have a return value, but if one wasn't expected, just exit, this is
-         * not a problem. For example, if the "Implicit Return" feature is
-         * enabled, methods will always return a value.
+         * Return value validation and possible repair.
          *
-         * 2) If the return value can be of any type, then we cannot perform any
-         * validation, exit.
+         * 1) Don't perform return value validation/repair if this feature
+         * has been disabled via a global option.
+         *
+         * 2) We have a return value, but if one wasn't expected, just exit,
+         * this is not a problem. For example, if the "Implicit Return"
+         * feature is enabled, methods will always return a value.
+         *
+         * 3) If the return value can be of any type, then we cannot perform
+         * any validation, just exit.
          */
-        if ((!predefined->info.expected_btypes) ||
+        if (acpi_gbl_disable_auto_repair ||
+            (!predefined->info.expected_btypes) ||
             (predefined->info.expected_btypes == ACPI_RTYPE_ALL)) {
                 goto cleanup;
         }