diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 6695535..e8efaac 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -142,7 +142,7 @@
 	create_sysfs_device_files(device);
 }
 
-static int acpi_device_unregister(struct acpi_device *device, int type)
+static void acpi_device_unregister(struct acpi_device *device, int type)
 {
 	spin_lock(&acpi_device_lock);
 	if (device->parent) {
@@ -158,7 +158,6 @@
 	acpi_detach_data(device->handle, acpi_bus_data_handler);
 	remove_sysfs_device_files(device);
 	kobject_unregister(&device->kobj);
-	return 0;
 }
 
 void acpi_bus_data_handler(acpi_handle handle, u32 function, void *context)
@@ -577,7 +576,7 @@
 	spin_unlock(&acpi_device_lock);
 }
 
-static int acpi_driver_detach(struct acpi_driver *drv)
+static void acpi_driver_detach(struct acpi_driver *drv)
 {
 	struct list_head *node, *next;
 
@@ -599,7 +598,6 @@
 		}
 	}
 	spin_unlock(&acpi_device_lock);
-	return_VALUE(0);
 }
 
 /**
@@ -617,9 +615,6 @@
 	if (acpi_disabled)
 		return_VALUE(-ENODEV);
 
-	if (!driver)
-		return_VALUE(-EINVAL);
-
 	spin_lock(&acpi_device_lock);
 	list_add_tail(&driver->node, &acpi_bus_drivers);
 	spin_unlock(&acpi_device_lock);
@@ -637,23 +632,16 @@
  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
  * devices that match the driver's criteria and unbinds.
  */
-int acpi_bus_unregister_driver(struct acpi_driver *driver)
+void acpi_bus_unregister_driver(struct acpi_driver *driver)
 {
-	int error = 0;
+	acpi_driver_detach(driver);
 
-	ACPI_FUNCTION_TRACE("acpi_bus_unregister_driver");
-
-	if (driver) {
-		acpi_driver_detach(driver);
-
-		if (!atomic_read(&driver->references)) {
-			spin_lock(&acpi_device_lock);
-			list_del_init(&driver->node);
-			spin_unlock(&acpi_device_lock);
-		}
-	} else
-		error = -EINVAL;
-	return_VALUE(error);
+	if (!atomic_read(&driver->references)) {
+		spin_lock(&acpi_device_lock);
+		list_del_init(&driver->node);
+		spin_unlock(&acpi_device_lock);
+	}
+	return;
 }
 
 EXPORT_SYMBOL(acpi_bus_unregister_driver);
diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index 6dca3d5..809eb50 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -327,7 +327,7 @@
 int acpi_bus_generate_event(struct acpi_device *device, u8 type, int data);
 int acpi_bus_receive_event(struct acpi_bus_event *event);
 int acpi_bus_register_driver(struct acpi_driver *driver);
-int acpi_bus_unregister_driver(struct acpi_driver *driver);
+void acpi_bus_unregister_driver(struct acpi_driver *driver);
 int acpi_bus_add(struct acpi_device **child, struct acpi_device *parent,
 		 acpi_handle handle, int type);
 int acpi_bus_trim(struct acpi_device *start, int rmdevice);