Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964821AbWAGFzm (ORCPT ); Sat, 7 Jan 2006 00:55:42 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964822AbWAGFzl (ORCPT ); Sat, 7 Jan 2006 00:55:41 -0500 Received: from HELIOUS.MIT.EDU ([18.248.3.87]:23965 "EHLO neo.rr.com") by vger.kernel.org with ESMTP id S964821AbWAGFzl (ORCPT ); Sat, 7 Jan 2006 00:55:41 -0500 Date: Sat, 7 Jan 2006 00:58:07 -0500 From: Adam Belay To: Dominik Brodowski , Patrick Mochel , Pavel Machek , Andrew Morton , Linux-pm mailing list , kernel list Subject: Re: [linux-pm] [patch] pm: fix runtime powermanagement's /sys interface Message-ID: <20060107055807.GB3184@neo.rr.com> Mail-Followup-To: Adam Belay , Dominik Brodowski , Patrick Mochel , Pavel Machek , Andrew Morton , Linux-pm mailing list , kernel list References: <20060105221334.GA925@isilmar.linta.de> <20060105222338.GG2095@elf.ucw.cz> <20060105222705.GA12242@isilmar.linta.de> <20060105230849.GN2095@elf.ucw.cz> <20060105234629.GA7298@isilmar.linta.de> <20060105235838.GC3339@elf.ucw.cz> <20060106001252.GE3339@elf.ucw.cz> <20060106150005.GA20242@isilmar.linta.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20060106150005.GA20242@isilmar.linta.de> User-Agent: Mutt/1.5.11 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1457 Lines: 37 On Fri, Jan 06, 2006 at 04:00:05PM +0100, Dominik Brodowski wrote: > Hi, > > On Thu, Jan 05, 2006 at 05:37:30PM -0800, Patrick Mochel wrote: > > And, appended is a patch to export PM controls for PCI devices. The file > > "pm_possible_states" exports the states a device supports, and "pm_state" > > exports the current state (and provides the interface for entering a > > state). > > Your patch doesn't handle the PM dependencies, unfortunately... > > Thanks, > Dominik Physical power dependencies are a very bus and platform specific matter. I don't expect to see much core level help or infustructure. I think in the PCI case, we would first require PCI bus power management support. This feature is currently nonexistent. As I understand, PCI express links are capable of handling much of this at the hardware level, so it's not especially important for newer hardware. At the moment, I think the biggest X86 pm dependency issue is ACPI power resources. Logical dependencies might be another matter. For example, if we have a bus-instance structure at the driver core level, it may make sense to call some sort of ->prepare_for_children mechansim before starting up a child device. Thanks, Adam - 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/