From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9D1EFC5B578 for ; Wed, 3 Jul 2019 23:02:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 79B1F218A0 for ; Wed, 3 Jul 2019 23:02:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727469AbfGCXCx (ORCPT ); Wed, 3 Jul 2019 19:02:53 -0400 Received: from cloudserver094114.home.pl ([79.96.170.134]:61215 "EHLO cloudserver094114.home.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727377AbfGCXCx (ORCPT ); Wed, 3 Jul 2019 19:02:53 -0400 Received: from 79.184.254.216.ipv4.supernova.orange.pl (79.184.254.216) (HELO kreacher.localnet) by serwer1319399.home.pl (79.96.170.134) with SMTP (IdeaSmtpServer 0.83.267) id 8010e3fd10758b8f; Thu, 4 Jul 2019 01:02:49 +0200 From: "Rafael J. Wysocki" To: Linux ACPI Cc: Linux PM , LKML , Mika Westerberg Subject: [PATCH] ACPI: PM: Unexport acpi_device_get_power() Date: Thu, 04 Jul 2019 01:02:49 +0200 Message-ID: <1970901.ZntFDt4DbR@kreacher> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org From: Rafael J. Wysocki Using acpi_device_get_power() outside of ACPI device initialization and ACPI sysfs is problematic due to the way in which power resources are handled by it, so unexport it and add a paragraph explaining the pitfalls to its kerneldoc comment. Signed-off-by: Rafael J. Wysocki --- On top of the linux-next branch in the linux-pm.git tree. --- drivers/acpi/device_pm.c | 6 +++++- drivers/acpi/internal.h | 7 +++++++ include/acpi/acpi_bus.h | 1 - 3 files changed, 12 insertions(+), 2 deletions(-) Index: linux-pm/drivers/acpi/device_pm.c =================================================================== --- linux-pm.orig/drivers/acpi/device_pm.c +++ linux-pm/drivers/acpi/device_pm.c @@ -66,6 +66,11 @@ static int acpi_dev_pm_explicit_get(stru * This function does not update the device's power.state field, but it may * update its parent's power.state field (when the parent's power state is * unknown and the device's power state turns out to be D0). + * + * Also, it does not update power resource reference counters to ensure that + * the power state returned by it will be persistent and it may return a power + * state shallower than previously set by acpi_device_set_power() for @device + * (if that power state depends on any power resources). */ int acpi_device_get_power(struct acpi_device *device, int *state) { @@ -130,7 +135,6 @@ int acpi_device_get_power(struct acpi_de return 0; } -EXPORT_SYMBOL(acpi_device_get_power); static int acpi_dev_pm_explicit_set(struct acpi_device *adev, int state) { Index: linux-pm/include/acpi/acpi_bus.h =================================================================== --- linux-pm.orig/include/acpi/acpi_bus.h +++ linux-pm/include/acpi/acpi_bus.h @@ -506,7 +506,6 @@ int acpi_bus_get_status(struct acpi_devi int acpi_bus_set_power(acpi_handle handle, int state); const char *acpi_power_state_string(int state); -int acpi_device_get_power(struct acpi_device *device, int *state); int acpi_device_set_power(struct acpi_device *device, int state); int acpi_bus_init_power(struct acpi_device *device); int acpi_device_fix_up_power(struct acpi_device *device); Index: linux-pm/drivers/acpi/internal.h =================================================================== --- linux-pm.orig/drivers/acpi/internal.h +++ linux-pm/drivers/acpi/internal.h @@ -139,8 +139,15 @@ int acpi_power_get_inferred_state(struct int acpi_power_on_resources(struct acpi_device *device, int state); int acpi_power_transition(struct acpi_device *device, int state); +/* -------------------------------------------------------------------------- + Device Power Management + -------------------------------------------------------------------------- */ +int acpi_device_get_power(struct acpi_device *device, int *state); int acpi_wakeup_device_init(void); +/* -------------------------------------------------------------------------- + Processor + -------------------------------------------------------------------------- */ #ifdef CONFIG_ARCH_MIGHT_HAVE_ACPI_PDC void acpi_early_processor_set_pdc(void); #else