From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Garzik Subject: Re: [patch 2/3] Expose Power Management Policy option to users Date: Mon, 11 Jun 2007 16:00:29 -0400 Message-ID: <466DA9DD.8080004@garzik.org> References: <20070611184146.448266229@intel.com> <20070611114820.5290a903.kristen.c.accardi@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from srv5.dvmed.net ([207.36.208.214]:47885 "EHLO mail.dvmed.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752133AbXFKUAd (ORCPT ); Mon, 11 Jun 2007 16:00:33 -0400 In-Reply-To: <20070611114820.5290a903.kristen.c.accardi@intel.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Kristen Carlson Accardi Cc: james.bottomley@steeleye.com, linux-ide@vger.kernel.org, linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, htejun@gmail.com Kristen Carlson Accardi wrote: > This patch will modify the scsi and ata subsystem to allow > users to set a power management policy for the link. > libata drivers can define a function (enable_pm) that will > perform hardware specific actions to enable whatever power > management policy the user sets up if the driver supports > it. This power management policy will be activated after > all disks have been enumerated and intialized. > > The scsi subsystem will create a new sysfs file for each > host in /sys/class/scsi_host called "link_power_management_policy". > This file can have 3 possible values: > > Value Meaning > ------------------------------------------------------------------- > min_power User wishes the link to conserve power as much as > possible, even at the cost of some performance > > max_performance User wants priority to be on performance, not power > savings > > medium_power User wants power savings, with less performance cost > than min_power (but less power savings as well). > > > Signed-off-by: Kristen Carlson Accardi seems OK at first glance, though I request that ata and scsi portions be split into separate patches