diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 75b7c57..0302dd4 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -1580,15 +1580,12 @@
 }
 EXPORT_SYMBOL_GPL(acpi_bus_trim);
 
-static int acpi_bus_scan_fixed(struct acpi_device *root)
+static int acpi_bus_scan_fixed(void)
 {
 	int result = 0;
 	struct acpi_device *device = NULL;
 	struct acpi_bus_ops ops;
 
-	if (!root)
-		return -ENODEV;
-
 	memset(&ops, 0, sizeof(ops));
 	ops.acpi_op_add = 1;
 	ops.acpi_op_start = 1;
@@ -1639,7 +1636,7 @@
 	/*
 	 * Enumerate devices in the ACPI namespace.
 	 */
-	result = acpi_bus_scan_fixed(acpi_root);
+	result = acpi_bus_scan_fixed();
 
 	if (!result)
 		result = acpi_bus_scan(acpi_root, &ops);