diff --git a/include/acpi/actbl2.h b/include/acpi/actbl2.h
index d8fec67e4c8c..42c78fecca7c 100644
--- a/include/acpi/actbl2.h
+++ b/include/acpi/actbl2.h
@@ -447,6 +447,12 @@ struct acpi_ivrs_device_hid {
 	u8 uid_length;
 };
 
+/* Values for uid_type above */
+
+#define ACPI_IVRS_UID_NOT_PRESENT   0
+#define ACPI_IVRS_UID_IS_INTEGER    1
+#define ACPI_IVRS_UID_IS_STRING     2
+
 /* 0x20, 0x21, 0x22: I/O Virtualization Memory Definition Block (IVMD) */
 
 struct acpi_ivrs_memory {