From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754916AbYHYIyo (ORCPT ); Mon, 25 Aug 2008 04:54:44 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753554AbYHYIyf (ORCPT ); Mon, 25 Aug 2008 04:54:35 -0400 Received: from cantor.suse.de ([195.135.220.2]:49335 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753515AbYHYIyf (ORCPT ); Mon, 25 Aug 2008 04:54:35 -0400 From: Oliver Neukum Organization: Novell To: Pavel Machek Subject: Re: autosuspend for SCSI devices Date: Mon, 25 Aug 2008 10:55:44 +0200 User-Agent: KMail/1.9.9 Cc: "Rafael J. Wysocki" , linux-pm@lists.linux-foundation.org, James.Bottomley@hansenpartnership.com, linux-kernel@vger.kernel.org, teheo@novell.com, stefanr@s5r6.in-berlin.de, Martin.Leisner@xerox.com References: <20080822105626.GA9475@elf.ucw.cz> <200808222252.52947.rjw@sisk.pl> <20080825081901.GA32128@elf.ucw.cz> In-Reply-To: <20080825081901.GA32128@elf.ucw.cz> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200808251055.45582.oneukum@suse.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am Montag 25 August 2008 10:19:01 schrieb Pavel Machek: > From: Alan Stern > > Add support for autosuspend/autoresume of the SCSI devices. Lowlevel > driver can use it to spin the disk down... and it is neccessary step > for powering down the controllers. > > Spinning down the disk is useful - saves ~0.5W here, and it is last > major thing we can do to save power on some small machines like > Kohjinsha subnotebooks. > > Signed-off-by: Pavel Machek Hi, firstly, it doesn't consider error handling before suspending. Secondly, it is simply not true that in SCSI suspending the disks is always necessary before suspending the controller. Regards Oliver