From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Torokhov Subject: Re: [PATCH] - race-free suspend. Was: Re: [linux-pm] [PATCH 0/8] Suspend block api (version 8) Date: Wed, 2 Jun 2010 16:32:44 -0700 Message-ID: <20100602233243.GA27666@core.coreip.homeip.net> References: <20100601113309.609349fd@notabene.brown> <20100601122012.1edeaf48@notabene.brown> <20100602153235.340a7852@notabene.brown> <20100602180614.729246ea@notabene.brown> <20100602210224.6ae2333f@notabene.brown> <20100602210521.54b9cd9b@schatten.dmk.lab> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20100602210521.54b9cd9b@schatten.dmk.lab> Sender: linux-kernel-owner@vger.kernel.org To: Florian Mickler Cc: Neil Brown , Arve =?iso-8859-1?B?SGr4bm5lduVn?= , Thomas Gleixner , "Rafael J. Wysocki" , Alan Stern , Felipe Balbi , Peter Zijlstra , "Paul@smtp1.linux-foundation.org" , LKML , Linux OMAP Mailing List , Linux PM , Alan Cox , James Bottomley List-Id: linux-omap@vger.kernel.org On Wed, Jun 02, 2010 at 09:05:21PM +0200, Florian Mickler wrote: > On Wed, 2 Jun 2010 21:02:24 +1000 > Neil Brown wrote: > > > > And this decision (to block suspend) really needs to be made in the driver, > > not in userspace? > > Well, it fits. The requirement is a direct consequence of the intimate > knowledge the driver has about the driven devices. That is not really true. A driver does have intimate knowledge of the device, however it does not necessarily have an idea about the data read from the device. Consider the gpio_matrix driver: Arve says that it has to continue scanning matrix once first interrupt arrvies. But it really depends on what key has been pressed - if user pressed KEY_SUSPEND or KEY_POWER it cmight be better if we did not wait for key release but initiated the action right away. The decision on how system reacts to a key press does not belong to the driver but really to userspace. -- Dmitry