From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jean Delvare Subject: Re: [lm-sensors] Fintek f71882fg ACPI conflict Date: Thu, 28 Jun 2012 14:40:35 +0200 Message-ID: <20120628144035.36ac75a0@endymion.delvare> References: <4FEA4C10.2060904@googlemail.com> <20120627171505.GB12712@roeck-us.net> <4FEB90A8.8050901@googlemail.com> <20120628014548.GA15994@srcf.ucam.org> <4FEC3CDF.7050901@googlemail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: Received: from zoneX.GCU-Squad.org ([194.213.125.0]:4700 "EHLO services.gcu-squad.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753179Ab2F1Mkq (ORCPT ); Thu, 28 Jun 2012 08:40:46 -0400 In-Reply-To: <4FEC3CDF.7050901@googlemail.com> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Michael Zintakis Cc: Matthew Garrett , linux-acpi@vger.kernel.org, Len Brown , lm-sensors@lm-sensors.org On Thu, 28 Jun 2012 12:15:43 +0100, Michael Zintakis wrote: > > That's the *good* outcome. The bad outcome involves these register > > accesses racing in a way that disables fan control or thermal trip > > points and risks causing hardware damage. It's not safe for two > > different codepaths to access the same hardware without having any kind > > of locking, so if your system firmware declares that ACPI is using the > > temperature device the hardware sensors framework will refuse to. > > All noted, thanks for the explanation - pretty hairy stuff! The tragic > thing is, I have no way of telling ACPI to *not* use or "implement" its > own fan, voltage, temperature management and let a more capable piece of > software (the f71882fg driver in this case) do that job! This has been my very claim for several years now. My next step is to find someone involved in the ACPI specification that would be willing to discuss the problem with me and implement a solution in the next ACPI specification. Don't hold your breath though, it will take years before the problem actually gets solved for the end user - if that ever happens. -- Jean Delvare