Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752607AbaJ0Ppx (ORCPT ); Mon, 27 Oct 2014 11:45:53 -0400 Received: from relay4-d.mail.gandi.net ([217.70.183.196]:52689 "EHLO relay4-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751163AbaJ0Pp1 (ORCPT ); Mon, 27 Oct 2014 11:45:27 -0400 X-Originating-IP: 83.155.44.161 Message-ID: <1414424673.30379.58.camel@hadess.net> Subject: Re: A desktop environment[1] kernel wishlist From: Bastien Nocera To: Geert Uytterhoeven Cc: John Stultz , Linux Kernel Mailing List Date: Mon, 27 Oct 2014 16:44:33 +0100 In-Reply-To: References: <1413881397.30379.7.camel@hadess.net> <1413911644.30379.12.camel@hadess.net> <1414419657.30379.51.camel@hadess.net> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.12.7 (3.12.7-1.fc21) Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2014-10-27 at 16:31 +0100, Geert Uytterhoeven wrote: > Hi Bastien, > > On Mon, Oct 27, 2014 at 3:20 PM, Bastien Nocera wrote: > > On Tue, 2014-10-21 at 20:24 +0200, Geert Uytterhoeven wrote: > >> On Tue, Oct 21, 2014 at 7:14 PM, Bastien Nocera wrote: > >> >> As for: 'Export of "wake reason" when the system wakes up (rtc alarm, > >> >> lid open, etc.) and wakealarm (/sys/class/rtc/foo/wakealarm) > >> >> documentation' > >> >> > >> >> Can you expand more on the rational for the need here? Is this for UI > >> >> for power debugging, or something else? > >> > > >> > No, it would be used for automating backups, or implementing > >> > suspend->hibernation transitions. For example, right before the machine > >> > suspends, I would schedule it to wake up in a hour. If I get woken up by > >> > the rtc alarm (and not by the user through a lid open), I might: > >> > - check that I'm plugged into the AC, it's night, and in the vicinity of > >> > the server that handles my backups and so backup the system. > >> > - check whether the battery is low, and hibernate the machine (if it > >> > supports it, obviously). > >> > >> Isn't this already available through /sys/kernel/debug/wakeup_sources > >> and/or the various power/wake* files in sysfs? > > > > That might very well be, but /sys/kernel/debug/wakeup_sources really > > isn't much of a user-space API. Where's the documentation for the > > various power/wake* files? > > The debugfs entry is indeed not documented. > Documentation for the others is just a git grep away: Fair enough, but apart from tallying up wakeup_count by hand, I'm not sure how I'm supposed to interface with that. It also doesn't fix the problem of knowing which event caused a wakeup (or when the last event occurred on a particular device) when this device can have multiple different reasons to wake up (see the WOL/connected suspend mentions earlier in the thread). -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/