diff --git a/include/acpi/actypes.h b/include/acpi/actypes.h
index ff8b3c913f2177..248242dca28d34 100644
--- a/include/acpi/actypes.h
+++ b/include/acpi/actypes.h
@@ -536,8 +536,14 @@ typedef u64 acpi_integer;
  * Can be used with access_width of struct acpi_generic_address and access_size of
  * struct acpi_resource_generic_register.
  */
-#define ACPI_ACCESS_BIT_WIDTH(size)     (1 << ((size) + 2))
-#define ACPI_ACCESS_BYTE_WIDTH(size)    (1 << ((size) - 1))
+#define ACPI_ACCESS_BIT_SHIFT		2
+#define ACPI_ACCESS_BYTE_SHIFT		-1
+#define ACPI_ACCESS_BIT_MAX		(31 - ACPI_ACCESS_BIT_SHIFT)
+#define ACPI_ACCESS_BYTE_MAX		(31 - ACPI_ACCESS_BYTE_SHIFT)
+#define ACPI_ACCESS_BIT_DEFAULT		(8 - ACPI_ACCESS_BIT_SHIFT)
+#define ACPI_ACCESS_BYTE_DEFAULT	(8 - ACPI_ACCESS_BYTE_SHIFT)
+#define ACPI_ACCESS_BIT_WIDTH(size)	(1 << ((size) + ACPI_ACCESS_BIT_SHIFT))
+#define ACPI_ACCESS_BYTE_WIDTH(size)	(1 << ((size) + ACPI_ACCESS_BYTE_SHIFT))
 
 /*******************************************************************************
  *