From patchwork Wed Jul 31 23:31:08 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Rafael J. Wysocki" X-Patchwork-Id: 1140169 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-pci-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=rjwysocki.net Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 45zV6m5WSkz9sDB for ; Thu, 1 Aug 2019 09:31:12 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730713AbfGaXbL (ORCPT ); Wed, 31 Jul 2019 19:31:11 -0400 Received: from cloudserver094114.home.pl ([79.96.170.134]:48065 "EHLO cloudserver094114.home.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730691AbfGaXbL (ORCPT ); Wed, 31 Jul 2019 19:31:11 -0400 Received: from 79.184.255.110.ipv4.supernova.orange.pl (79.184.255.110) (HELO kreacher.localnet) by serwer1319399.home.pl (79.96.170.134) with SMTP (IdeaSmtpServer 0.83.275) id 962226490afa9733; Thu, 1 Aug 2019 01:31:08 +0200 From: "Rafael J. Wysocki" To: Linux ACPI Cc: Linux PM , Linux PCI , LKML , Mika Westerberg , Bjorn Helgaas , Mario Limonciello , Kai-Heng Feng Subject: [PATCH] ACPI: PM: Fix regression in acpi_device_set_power() Date: Thu, 01 Aug 2019 01:31:08 +0200 Message-ID: <4199592.UtrPOv3ZmA@kreacher> MIME-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org From: Rafael J. Wysocki Commit f850a48a0799 ("ACPI: PM: Allow transitions to D0 to occur in special cases") overlooked the fact that acpi_power_transition() may change the power.state value for the target device and if that happens, it may confuse acpi_device_set_power() and cause it to omit the _PS0 evaluation which on some systems is necessary to change power states of devices from low-power to D0. Fix that by saving the current value of power.state for the target device before passing it to acpi_power_transition() and using the saved value in a subsequent check. Fixes: f850a48a0799 ("ACPI: PM: Allow transitions to D0 to occur in special cases") Reported-by: Kai-Heng Feng Reported-by: Mario Limonciello Signed-off-by: Rafael J. Wysocki Tested-by: Kai-Heng Feng Tested-by: Mario Limonciello --- drivers/acpi/device_pm.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) Index: linux-pm/drivers/acpi/device_pm.c =================================================================== --- linux-pm.orig/drivers/acpi/device_pm.c +++ linux-pm/drivers/acpi/device_pm.c @@ -236,13 +236,15 @@ int acpi_device_set_power(struct acpi_de if (device->power.flags.power_resources) result = acpi_power_transition(device, target_state); } else { + int cur_state = device->power.state; + if (device->power.flags.power_resources) { result = acpi_power_transition(device, ACPI_STATE_D0); if (result) goto end; } - if (device->power.state == ACPI_STATE_D0) { + if (cur_state == ACPI_STATE_D0) { int psc; /* Nothing to do here if _PSC is not present. */