diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index ad06798..89c112e 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -276,6 +276,13 @@
 {
 	const struct acpi_device_id *id;
 
+	/*
+	 * If the device is not present, it is unnecessary to load device
+	 * driver for it.
+	 */
+	if (!device->status.present)
+		return -ENODEV;
+
 	if (device->flags.hardware_id) {
 		for (id = ids; id->id[0]; id++) {
 			if (!strcmp((char*)id->id, device->pnp.hardware_id))
@@ -1222,15 +1229,18 @@
 			result = -ENODEV;
 			goto end;
 		}
-		if (!device->status.present) {
-			/* Bay and dock should be handled even if absent */
-			if (!ACPI_SUCCESS(
-			     acpi_is_child_device(device, acpi_bay_match)) &&
-			    !ACPI_SUCCESS(
-			     acpi_is_child_device(device, acpi_dock_match))) {
-					result = -ENODEV;
-					goto end;
-			}
+		/*
+		 * When the device is neither present nor functional, the
+		 * device should not be added to Linux ACPI device tree.
+		 * When the status of the device is not present but functinal,
+		 * it should be added to Linux ACPI tree. For example : bay
+		 * device , dock device.
+		 * In such conditions it is unncessary to check whether it is
+		 * bay device or dock device.
+		 */
+		if (!device->status.present && !device->status.functional) {
+			result = -ENODEV;
+			goto end;
 		}
 		break;
 	default:
@@ -1411,7 +1421,12 @@
 		 * TBD: Need notifications and other detection mechanisms
 		 *      in place before we can fully implement this.
 		 */
-		if (child->status.present) {
+		 /*
+		 * When the device is not present but functional, it is also
+		 * necessary to scan the children of this device.
+		 */
+		if (child->status.present || (!child->status.present &&
+					child->status.functional)) {
 			status = acpi_get_next_object(ACPI_TYPE_ANY, chandle,
 						      NULL, NULL);
 			if (ACPI_SUCCESS(status)) {