From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mika Westerberg Subject: Re: [PATCH] PCI: Power on bridges before scanning new devices Date: Wed, 25 May 2016 00:13:09 +0300 Message-ID: <20160524211309.GH1789@lahna.fi.intel.com> References: <20160519231234.GB1785@al> <1463991648-85051-1-git-send-email-mika.westerberg@linux.intel.com> <20160523200042.GB24375@localhost> <20160523215015.GA31479@localhost> <20160524122357.GA20453@localhost> <20160524125323.GE1789@lahna.fi.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mga02.intel.com ([134.134.136.20]:35076 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751278AbcEXVNP (ORCPT ); Tue, 24 May 2016 17:13:15 -0400 Content-Disposition: inline In-Reply-To: <20160524125323.GE1789@lahna.fi.intel.com> Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: Bjorn Helgaas Cc: Bjorn Helgaas , Peter Wu , "Rafael J. Wysocki" , Lukas Wunner , linux-pci@vger.kernel.org, linux-pm@vger.kernel.org, Valdis Kletnieks , Dave Airlie On Tue, May 24, 2016 at 03:53:23PM +0300, Mika Westerberg wrote: > > I dropped "ACPI / hotplug / PCI: Runtime resume bridge before rescan" > > on the assumption that "PCI: Power on bridges before scanning new > > devices" is sufficient to cover both the ACPI and the generic PCi > > rescan cases, but I'd like some reassurance about that. > > I agree with your reasoning that the patch should not be needed anymore. > However, I have the machine which needed that patch at home so I'm not > able to test it now. I'll do that later today when I get back home. I tried now on my Lenovo Yoga 900 laptop and unfortunately "PCI: Power on bridges before scanning new devices" seems not to be enough. This machine has SD-card reader connected to one PCIe port and once I unload the sdhci-pci driver and enable runtime PM for the device, next system suspend/resume cycle loses the SD-card reader PCI device. I will investigate more tomorrow -- it is getting late here. Anyway, maybe it is safer to postpone this series for v4.8 to give it more testing time in -next.