Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751533Ab0DYCar (ORCPT ); Sat, 24 Apr 2010 22:30:47 -0400 Received: from ogre.sisk.pl ([217.79.144.158]:39730 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750994Ab0DYCap convert rfc822-to-8bit (ORCPT ); Sat, 24 Apr 2010 22:30:45 -0400 From: "Rafael J. Wysocki" To: Alan Stern Subject: Re: [linux-pm] [PATCH 8/9] Input: Block suspend while event queue is not empty. Date: Sun, 25 Apr 2010 04:30:30 +0200 User-Agent: KMail/1.12.4 (Linux/2.6.34-rc4-rjw; KDE/4.3.5; x86_64; ; ) Cc: Arve =?iso-8859-1?q?Hj=F8nnev=E5g?= , Dmitry Torokhov , Randy Dunlap , =?iso-8859-1?q?M=E1rton_N=E9meth?= , Thadeu Lima de Souza Cascardo , linux-input@vger.kernel.org, Sven Neumann , linux-kernel@vger.kernel.org, Henrik Rydberg , Jiri Kosina , linux-pm@lists.linux-foundation.org, Tero Saarni , Matthew Garrett References: In-Reply-To: MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 8BIT Message-Id: <201004250430.31054.rjw@sisk.pl> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1964 Lines: 42 On Saturday 24 April 2010, Alan Stern wrote: > On Fri, 23 Apr 2010, Arve Hj?nnev?g wrote: > > > On Fri, Apr 23, 2010 at 2:08 PM, Dmitry Torokhov > > wrote: > > > On Friday 23 April 2010 01:56:25 pm Randy Dunlap wrote: > > >> On Thu, 22 Apr 2010 18:08:57 -0700 Arve Hj?nnev?g wrote: > > >> > Add an ioctl, EVIOCSSUSPENDBLOCK, to enable a suspend_blocker that will > > >> > block suspend while the event queue is not empty. This allows userspace > > >> > code to process input events while the device appears to be asleep. > > >> > > >> All new ioctls need to be added to Documentation/ioctl/ioctl-number.txt, > > >> please. > > > > > > I do not see the reason for it to be in the kernel still. Have a process > > > that listens to all input devices (or subset of them), once events stop > > > coming initiate suspend. This solution is not practical with the Android user space AFAICT. > > I think the document added by the first patch explains this. The > > solution you propose above will ignore a wakeup key pressed right > > after user space decides to initiate suspend. > > Is there some reason why this feature needs to be enabled by an > ioctl? Why not make this suspend blocker permanently enabled? The ioctl is there so that user space can use suspend blockers, which is needed because only user space know that some activities are going to continue and therefore the system should not be suspended (like playing music "in the background"). >From all of the interfaces that could be used for this purpose ioctl appears to be the most convenient (we need something that is per process and allows us to carry out four operations: creat, destroy, activate, deactivate). Rafael -- 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/