diff --git a/src/mainboard/google/kahlee/dsdt.asl b/src/mainboard/google/kahlee/dsdt.asl
index db81393..e5276d3 100644
--- a/src/mainboard/google/kahlee/dsdt.asl
+++ b/src/mainboard/google/kahlee/dsdt.asl
@@ -45,6 +45,9 @@
 	/* Contains the Sleep methods (WAK, PTS, GTS, etc.) */
 	#include <variant/acpi/sleep.asl>
 
+	/* Contains _SWS methods */
+	#include <acpi_wake_source.asl>
+
 	/* System Bus */
 	Scope(\_SB) { /* Start \_SB scope */
 		/* global utility methods expected within the \_SB scope */
diff --git a/src/soc/amd/stoneyridge/acpi/acpi_wake_source.asl b/src/soc/amd/stoneyridge/acpi/acpi_wake_source.asl
new file mode 100644
index 0000000..fa01802
--- /dev/null
+++ b/src/soc/amd/stoneyridge/acpi/acpi_wake_source.asl
@@ -0,0 +1,32 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2015 Google Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+Scope (\_SB)
+{
+	Method (_SWS)
+	{
+		/* Index into PM1 for device that caused wake */
+		Return (\PM1I)
+	}
+}
+
+Scope (\_GPE)
+{
+	Method (_SWS)
+	{
+		/* Index into GPE for device that caused wake */
+		Return (\GPEI)
+	}
+}