Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932274AbWJEVqG (ORCPT ); Thu, 5 Oct 2006 17:46:06 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932252AbWJEVqA (ORCPT ); Thu, 5 Oct 2006 17:46:00 -0400 Received: from iolanthe.rowland.org ([192.131.102.54]:55556 "HELO iolanthe.rowland.org") by vger.kernel.org with SMTP id S932274AbWJEVpZ (ORCPT ); Thu, 5 Oct 2006 17:45:25 -0400 Date: Thu, 5 Oct 2006 17:45:25 -0400 (EDT) From: Alan Stern X-X-Sender: stern@iolanthe.rowland.org To: Oliver Neukum cc: Pavel Machek , , Subject: Re: [linux-usb-devel] error to be returned while suspended In-Reply-To: <200610052325.39690.oliver@neukum.org> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1229 Lines: 36 On Thu, 5 Oct 2006, Oliver Neukum wrote: > I have a few observations, but no solution either: > - if root tells a device to suspend, it shall do so Probably everyone will agree on that. > - the issues of manual & automatic suspend and remote wakeup are orthogonal Except for the fact that remote wakeup kicks in only when a device is suspended. > - there should be a common API for all devices It would be nice, wouldn't it? But we _already_ have several vastly different power-management APIs. Consider for example DPMI and IDE spindown. > - there's no direct connection between power save and open() Why shouldn't a device always be put into a power-saving mode whenever it isn't open? Agreed, you might want to reduce its power usage at times even when it is open... > The question when a device is in use is far from trivial. Yes. It has to be decided by each individual driver. For simple character-oriented devices, "open" is a good first start. Alan Stern - 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/