Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752260AbdFHAN3 (ORCPT ); Wed, 7 Jun 2017 20:13:29 -0400 Received: from cloudserver094114.home.net.pl ([79.96.170.134]:63448 "EHLO cloudserver094114.home.net.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751927AbdFHANX (ORCPT ); Wed, 7 Jun 2017 20:13:23 -0400 From: "Rafael J. Wysocki" To: Linux ACPI Cc: Linux PCI , Linux PM , Bjorn Helgaas , LKML , Mika Westerberg , Srinivas Pandruvada , Linux USB , Mathias Nyman , Felipe Balbi , Mario Limonciello , Andy Shevchenko , Dominik Brodowski , Hans De Goede Subject: [PATCH 2/6] USB / PCI / PM: Allow the PCI core to do the resume cleanup Date: Thu, 08 Jun 2017 02:02:49 +0200 Message-ID: <1565826.hIbT8kZpDn@aspire.rjw.lan> User-Agent: KMail/4.14.10 (Linux/4.12.0-rc1+; KDE/4.14.9; x86_64; ; ) In-Reply-To: <8918199.uo13RZ8hZk@aspire.rjw.lan> References: <8918199.uo13RZ8hZk@aspire.rjw.lan> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1688 Lines: 45 From: Rafael J. Wysocki hcd_pci_resume_noirq() used as a universal _resume_noirq handler for PCI USB controllers calls pci_back_from_sleep() which is unnecessary and may become problematic. It is unnecessary, because the PCI bus type carries out post-suspend cleanup of all PCI devices during resume and that covers all things done by the pci_back_from_sleep(). There is no reason why USB cannot follow all of the other PCI devices in that respect. It will become problematic after subsequent changes that make it possible to go back to sleep again after executing dpm_resume_noirq() if no valid system wakeup events have been detected at that point. Namely, calling pci_back_from_sleep() at the _resume_noirq stage will cause the wakeup status of the devices in question to be cleared and if any of them has triggered system wakeup, that event may be missed then. For the above reasons, drop the pci_back_from_sleep() invocation from hcd_pci_resume_noirq(). Signed-off-by: Rafael J. Wysocki --- drivers/usb/core/hcd-pci.c | 7 +------ 1 file changed, 1 insertion(+), 6 deletions(-) Index: linux-pm/drivers/usb/core/hcd-pci.c =================================================================== --- linux-pm.orig/drivers/usb/core/hcd-pci.c +++ linux-pm/drivers/usb/core/hcd-pci.c @@ -584,12 +584,7 @@ static int hcd_pci_suspend_noirq(struct static int hcd_pci_resume_noirq(struct device *dev) { - struct pci_dev *pci_dev = to_pci_dev(dev); - - powermac_set_asic(pci_dev, 1); - - /* Go back to D0 and disable remote wakeup */ - pci_back_from_sleep(pci_dev); + powermac_set_asic(to_pci_dev(dev), 1); return 0; }