ACPI: Introduce acpi_device_sleep_wake function

The currect ACPI code attempts to execute _PSW at three different
places and in one of them only it tries to execute _DSW before _PSW,
which is inconsistent with the other two cases.

Move the execution of _DSW and _PSW into a separate function called
acpi_device_sleep_wake() and call it wherever appropriate instead of
executing _DSW and/or _PSW directly.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 6d85289..f276890 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -691,9 +691,7 @@
 	acpi_status status = 0;
 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 	union acpi_object *package = NULL;
-	union acpi_object in_arg[3];
-	struct acpi_object_list arg_list = { 3, in_arg };
-	acpi_status psw_status = AE_OK;
+	int psw_error;
 
 	struct acpi_device_id button_device_ids[] = {
 		{"PNP0C0D", 0},
@@ -725,39 +723,11 @@
 	 * So it is necessary to call _DSW object first. Only when it is not
 	 * present will the _PSW object used.
 	 */
-	/*
-	 * Three agruments are needed for the _DSW object.
-	 * Argument 0: enable/disable the wake capabilities
-	 * When _DSW object is called to disable the wake capabilities, maybe
-	 * the first argument is filled. The value of the other two agruments
-	 * is meaningless.
-	 */
-	in_arg[0].type = ACPI_TYPE_INTEGER;
-	in_arg[0].integer.value = 0;
-	in_arg[1].type = ACPI_TYPE_INTEGER;
-	in_arg[1].integer.value = 0;
-	in_arg[2].type = ACPI_TYPE_INTEGER;
-	in_arg[2].integer.value = 0;
-	psw_status = acpi_evaluate_object(device->handle, "_DSW",
-						&arg_list, NULL);
-	if (ACPI_FAILURE(psw_status) && (psw_status != AE_NOT_FOUND))
-		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "error in evaluate _DSW\n"));
-	/*
-	 * When the _DSW object is not present, OSPM will call _PSW object.
-	 */
-	if (psw_status == AE_NOT_FOUND) {
-		/*
-		 * Only one agruments is required for the _PSW object.
-		 * agrument 0: enable/disable the wake capabilities
-		 */
-		arg_list.count = 1;
-		in_arg[0].integer.value = 0;
-		psw_status = acpi_evaluate_object(device->handle, "_PSW",
-						&arg_list, NULL);
-		if (ACPI_FAILURE(psw_status) && (psw_status != AE_NOT_FOUND))
-			ACPI_DEBUG_PRINT((ACPI_DB_INFO, "error in "
-						"evaluate _PSW\n"));
-	}
+	psw_error = acpi_device_sleep_wake(device, 0, 0, 0);
+	if (psw_error)
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+				"error in _DSW or _PSW evaluation\n"));
+
 	/* Power button, Lid switch always enable wakeup */
 	if (!acpi_match_device_ids(device, button_device_ids))
 		device->wakeup.flags.run_wake = 1;