From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Rafael J. Wysocki" Subject: Re: [patch update 3] PM: Introduce core framework for run-time PM of I/O devices Date: Tue, 23 Jun 2009 01:02:27 +0200 Message-ID: <200906230102.29318.rjw@sisk.pl> References: Mime-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Return-path: Received: from ogre.sisk.pl ([217.79.144.158]:60886 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752423AbZFVXBs (ORCPT ); Mon, 22 Jun 2009 19:01:48 -0400 In-Reply-To: Content-Disposition: inline Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Alan Stern Cc: Oliver Neukum , Magnus Damm , linux-pm@lists.linux-foundation.org, ACPI Devel Maling List , Ingo Molnar , LKML , Greg KH On Monday 22 June 2009, Alan Stern wrote: > On Mon, 22 Jun 2009, Rafael J. Wysocki wrote: > > > > Again, this boils down to how drivers decide to use the async > > > interface. I can see justifications for both pm_request_resume_get > > > (which would always increment the counter) and pm_request_resume (which > > > would increment the counter only if a work item had to be queued). > > > > OK, so this means we should provide both at the core level and let the drivers > > decide which one to use. > > > > I think in both cases the caller would be responsible for decrementing the > > counter? > > Sure. They could call pm_runtime_put just once at the end of their > runtime_resume method (assuming they used pm_request_resume), or they > could call it at every place where some deferred work was finished > (assuming they used pm_request_resume_get). > > > > Okay, we don't need it then. I forgot to mention in the previous > > > message that there also has to be a pm_runtime_del() routine, which > > > should cancel pending workqueue items and set the counter to some high > > > value so that no new items are added. > > > > Should that be called by device_pm_remove()? I think so. > > Yes. I suppose it could be named pm_runtime_remove. Either would be > okay. OK I'm sending a new version of the $subject patch, containing these changes among other things, in a new thread. Best, Rafael