From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752988Ab0APWan (ORCPT ); Sat, 16 Jan 2010 17:30:43 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752904Ab0APWam (ORCPT ); Sat, 16 Jan 2010 17:30:42 -0500 Received: from ogre.sisk.pl ([217.79.144.158]:39245 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752580Ab0APWal (ORCPT ); Sat, 16 Jan 2010 17:30:41 -0500 From: "Rafael J. Wysocki" To: Pavel Machek Subject: Re: [suspend/resume] Re: userspace notification from module Date: Sat, 16 Jan 2010 23:31:15 +0100 User-Agent: KMail/1.12.3 (Linux/2.6.33-rc3-rjw; KDE/4.3.3; x86_64; ; ) Cc: Stanislav Brabec , Eric Miao , "Bart?omiej Zimo?" , Andy Walls , Daniel Borkmann , linux-kernel@vger.kernel.org, rpurdie@rpsys.net, lenz@cs.wisc.edu, Dirk@opfer-online.de, arminlitzel@web.de, Cyril Hrubis , thommycheck@gmail.com, "linux-arm-kernel" , dbaryshkov@gmail.com, omegamoon@gmail.com, zaurus-devel@www.linuxtogo.org References: <686edb2c.6263643a.4b3f4a3b.b60b3@o2.pl> <20100116221929.GB8425@elf.ucw.cz> <20100116222529.GA8618@elf.ucw.cz> In-Reply-To: <20100116222529.GA8618@elf.ucw.cz> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201001162331.15405.rjw@sisk.pl> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Saturday 16 January 2010, Pavel Machek wrote: > > > IMHO it should just plain shutdown in that case. Suspending doesn't really > > > solve the problem, because the battery is going to drain still. Unless you > > > mean suspend=hibernate, but I guess you don't. > > BTW I was talking spitz before, but there's collie, too. It was > shipped in configuration where all user data was in RAM and RAMdisk -- > no writable flash. On such machine, shutdown is never option. (And > yes, such design was very common in windowsCE days). > > Spitz got disk, but inherited that powermanagement design; and it > works very well. > > And now, if you want collie for a year (or two), you can have > mine... it still works and battery still lasted for 5 hours 2 years > ago -- not bad for 10 year old battery. You'll note that it is very > different design from PC. Well, I guess I wouldn't have the time to study it anyway, so thanks. :-) All in all, it looks like these particular platforms are just specific design having special requirements. And even on these platforms sending a battery critical notification to the user space before the kernel emergency suspends (or shuts down or whatever) the system seems to be a good idea in general. Rafael