Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753265AbYFBRo4 (ORCPT ); Mon, 2 Jun 2008 13:44:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751376AbYFBRor (ORCPT ); Mon, 2 Jun 2008 13:44:47 -0400 Received: from srv5.dvmed.net ([207.36.208.214]:43471 "EHLO mail.dvmed.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751165AbYFBRop (ORCPT ); Mon, 2 Jun 2008 13:44:45 -0400 Message-ID: <4844316B.1080405@garzik.org> Date: Mon, 02 Jun 2008 13:44:11 -0400 From: Jeff Garzik User-Agent: Thunderbird 2.0.0.14 (X11/20080501) MIME-Version: 1.0 To: kristen.c.accardi@intel.com CC: Mark Lord , Alan Cox , Pavel Machek , Theodore Tso , linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] ata: ahci: power off unused ports References: <20080508161008.59361de5@appleyard> <20080527030854.GC7515@mit.edu> <20080527143202.4bab5bf0@appleyard> <20080527225926.GE6843@mit.edu> <20080527163251.04054a74@appleyard> <20080531080015.GG5405@ucw.cz> <4842F5A8.9020708@garzik.org> <20080602080440.25fc663c@core> <4843A4A7.3020809@garzik.org> <4843EF88.2040606@rtr.ca> <20080602095710.1b0de376@appleyard> In-Reply-To: <20080602095710.1b0de376@appleyard> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Score: -4.4 (----) X-Spam-Report: SpamAssassin version 3.2.4 on srv5.dvmed.net summary: Content analysis details: (-4.4 points, 5.0 required) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1751 Lines: 48 Kristen Carlson Accardi wrote: > On Mon, 02 Jun 2008 09:03:04 -0400 > Mark Lord wrote: > >> Jeff Garzik wrote: >>> Alan Cox wrote: >>>>> If you are talking about SATA -- incorrect. >>>>> >>>>> The patch deals with policy, and the user MUST have the ability to >>>>> control this stuff. Otherwise you create a situation where the user >>>>> might be denied hotplug use in valid cases, or similar negative >>>>> situations. >>>> The policy isn't however complicated. Tejun added the stuff for forcing >>>> cable type and mode on setup and has therefore written all the per device >>>> setup code we might need. Alternatively a single >>>> >>>> foo=1/0 >>>> >>>> option has been fine for acpi and will do fine for this. Total additional >>>> cost - 1 line. >>> The key requirement is per-port control. Ideally via hdparm or another >>> userspace tool, but kernel command line (module options) or sysfs would >>> be just fine too. And agreed, the minimal you need is simply 1/0 for >>> the port's policy. >> .. >> >> Btw.. hdparm-8.7 (unreleased) can grok /sys now, so that interface is >> as good as any from a userspace viewpoint now. >> >> For the power-off of unused ports, the current patch still sounds >> extremely vendor-specific (Intel). > > Wrong - this patch is implemented according to the AHCI spec and > has absolutely nothing vendor specific in it. ITHM AHCI-specific, and not usable by non-AHCI SATA controllers -- which we would want in any solution. Jeff -- 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/