From patchwork Thu Apr 21 21:57:42 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rafael Wysocki X-Patchwork-Id: 726041 Received: from smtp1.linux-foundation.org (smtp1.linux-foundation.org [140.211.169.13]) by demeter1.kernel.org (8.14.4/8.14.3) with ESMTP id p3LLxXV0028095 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=FAIL) for ; Thu, 21 Apr 2011 21:59:53 GMT Received: from daredevil.linux-foundation.org (localhost [127.0.0.1]) by smtp1.linux-foundation.org (8.14.2/8.13.5/Debian-3ubuntu1.1) with ESMTP id p3LLvooq030864; Thu, 21 Apr 2011 14:57:51 -0700 Received: from ogre.sisk.pl (ogre.sisk.pl [217.79.144.158]) by smtp1.linux-foundation.org (8.14.2/8.13.5/Debian-3ubuntu1.1) with ESMTP id p3LLvlRg030855 for ; Thu, 21 Apr 2011 14:57:48 -0700 Received: from localhost (localhost.localdomain [127.0.0.1]) by ogre.sisk.pl (Postfix) with ESMTP id DEA5E1AC27A; Thu, 21 Apr 2011 23:56:58 +0200 (CEST) Received: from ogre.sisk.pl ([127.0.0.1]) by localhost (ogre.sisk.pl [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 32067-03; Thu, 21 Apr 2011 23:56:37 +0200 (CEST) Received: from ferrari.rjw.lan (220-bem-13.acn.waw.pl [82.210.184.220]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by ogre.sisk.pl (Postfix) with ESMTP id AE6C31AB644; Thu, 21 Apr 2011 23:56:37 +0200 (CEST) From: "Rafael J. Wysocki" To: Linux PM mailing list Date: Thu, 21 Apr 2011 23:57:42 +0200 User-Agent: KMail/1.13.6 (Linux/2.6.39-rc4+; KDE/4.6.0; x86_64; ; ) MIME-Version: 1.0 Message-Id: <201104212357.43052.rjw@sisk.pl> X-Virus-Scanned: amavisd-new at ogre.sisk.pl using MkS_Vir for Linux Received-SPF: pass (localhost is always allowed.) X-Spam-Status: No, hits=-5.44 required=5 tests=AWL, BAYES_00, OSDL_HEADER_SUBJECT_BRACKETED, PATCH_SUBJECT_OSDL X-Spam-Checker-Version: SpamAssassin 3.2.4-osdl_revision__1.47__ X-MIMEDefang-Filter: lf$Revision: 1.188 $ X-Scanned-By: MIMEDefang 2.63 on 140.211.169.21 Cc: Greg Kroah-Hartman , LKML , Tino Keitel Subject: [linux-pm] [PATCH] PM / Wakeup: Fix initialization of wakeup-related device sysfs files X-BeenThere: linux-pm@lists.linux-foundation.org X-Mailman-Version: 2.1.9 Precedence: list List-Id: Linux power management List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-pm-bounces@lists.linux-foundation.org Errors-To: linux-pm-bounces@lists.linux-foundation.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.6 (demeter1.kernel.org [140.211.167.41]); Thu, 21 Apr 2011 21:59:53 +0000 (UTC) From: Rafael J. Wysocki It turns out that some PCI devices are only found to be wakeup-capable during registration, in which case, when device_set_wakeup_capable() is called, device_is_registered() already returns 'true' for the given device, but dpm_sysfs_add() hasn't been called for it yet. This leads to situations in which the device's power.can_wakeup flag is not set as requested because of failing wakeup_sysfs_add() and its wakeup-related sysfs files are not created, although they should be present. This is a post-2.6.38 regression introduced by commit cb8f51bdadb7969139c2e39c2defd4cde98c1 (PM: Do not create wakeup sysfs files for devices that cannot wake up). To work around this problem initialize the device's power.entry field to an empty list head and make device_set_wakeup_capable() check if it is still empty before attempting to add the devices wakeup-related sysfs files with wakeup_sysfs_add(). Namely, if power.entry is still empty at this point, device_pm_add() hasn't been called yet for the device and its wakeup-related files will be created later, so device_set_wakeup_capable() doesn't have to create them. Reported-by: Tino Keitel Signed-off-by: Rafael J. Wysocki --- drivers/base/power/main.c | 1 + drivers/base/power/wakeup.c | 2 +- 2 files changed, 2 insertions(+), 1 deletion(-) Index: linux-2.6/drivers/base/power/main.c =================================================================== --- linux-2.6.orig/drivers/base/power/main.c +++ linux-2.6/drivers/base/power/main.c @@ -63,6 +63,7 @@ void device_pm_init(struct device *dev) dev->power.wakeup = NULL; spin_lock_init(&dev->power.lock); pm_runtime_init(dev); + INIT_LIST_HEAD(&dev->power.entry); } /** Index: linux-2.6/drivers/base/power/wakeup.c =================================================================== --- linux-2.6.orig/drivers/base/power/wakeup.c +++ linux-2.6/drivers/base/power/wakeup.c @@ -258,7 +258,7 @@ void device_set_wakeup_capable(struct de if (!!dev->power.can_wakeup == !!capable) return; - if (device_is_registered(dev)) { + if (device_is_registered(dev) && !list_empty(&dev->power.entry)) { if (capable) { if (wakeup_sysfs_add(dev)) return;