Index: sys/dev/acpica/acpi.c
===================================================================
--- sys/dev/acpica/acpi.c
+++ sys/dev/acpica/acpi.c
@@ -2402,6 +2402,16 @@
 }
 
 /*
+ * Check if an acpi method exists within a device handle.
+ */
+BOOLEAN
+acpi_HasMethod(ACPI_HANDLE h, char *method)
+{
+	ACPI_HANDLE tmp;
+	return ACPI_SUCCESS(acpi_GetHandleInScope(h, method, &tmp));
+}
+
+/*
  * Allocate a buffer with a preset data size.
  */
 ACPI_BUFFER *
Index: sys/dev/acpica/acpivar.h
===================================================================
--- sys/dev/acpica/acpivar.h
+++ sys/dev/acpica/acpivar.h
@@ -336,6 +336,7 @@
 BOOLEAN		acpi_BatteryIsPresent(device_t dev);
 ACPI_STATUS	acpi_GetHandleInScope(ACPI_HANDLE parent, char *path,
 		    ACPI_HANDLE *result);
+BOOLEAN		acpi_HasMethod(ACPI_HANDLE h, char *method);
 ACPI_BUFFER	*acpi_AllocBuffer(int size);
 ACPI_STATUS	acpi_ConvertBufferToInteger(ACPI_BUFFER *bufp,
 		    UINT32 *number);