Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753846AbYKXQhG (ORCPT ); Mon, 24 Nov 2008 11:37:06 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753288AbYKXQgx (ORCPT ); Mon, 24 Nov 2008 11:36:53 -0500 Received: from mail.suse.de ([195.135.220.2]:42110 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752935AbYKXQgw (ORCPT ); Mon, 24 Nov 2008 11:36:52 -0500 From: Thomas Renninger To: Tom Hughes Subject: Re: [PATCH 1/1] cpufreq: eeepc 900 frequency scaling driver Date: Mon, 24 Nov 2008 17:36:52 +0100 User-Agent: KMail/1.9.10 Cc: Cristiano Prisciandaro , Dave Jones , cpufreq@vger.kernel.org, linux-kernel@vger.kernel.org, acpi4asus-user@lists.sourceforge.net References: <1227454026.7262.59.camel@localhost> <492A7632.4040106@compton.nu> <200811241613.25557.trenn@suse.de> In-Reply-To: <200811241613.25557.trenn@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200811241736.53067.trenn@suse.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2520 Lines: 62 On Monday 24 November 2008 04:13:24 pm Thomas Renninger wrote: > On Monday 24 November 2008 10:38:58 am Tom Hughes wrote: > > Cristiano Prisciandaro wrote: > > > From: Cristiano Prisciandaro > > > > > > The bios of the eeepc 900 exposes an acpi method that allows clocking > > > the cpu to 630/900 MHz. This driver allows controlling the frequency > > > switch through the cpufreq subsystem. > > > > I should perhaps add at this point that I have an alternative patch > > based on Cristiano's code, which adds this cpufreq driver to the > > existing eeepc-laptop module rather than creating a separate module for > > it. > > > > Personally I'm quite happy with either solution so I'll leave it to you > > to decide what is the best way to go, but my patch is available if you > > want it. > > Either way, shouldn't you be able to provide a dmi matching module alias: > MODULE_ALIAS("dmi:...") > for autoloading? > > Or are these two cpufreq functions part of an ACPI device you could match > for, then it should get an ACPI driver? Oh, they are part of this general Asus \\_SB.ATKD device, which is only used by asus_laptop.c until now? I don't know \\_SB.ATKD in detail, but it has not a HID to match against and contains ASUS specific ACPI helper functions? Looks like a growing mess in the ASUS ACPI area... Some more questions: Why are they providing their own cpufreq interface and not following the spec (providing _PSS, ..)? Could it be that you are only throttling the CPU? Are these functions already used by the ACPI tables internally? - could be dangerous - could be helpful -> Is there some upper level device/interface in ASL? Could it happen that upcoming machines provide this interface (the two ACPI functions) and also can do real CPU frequency/volt switching, e.g. via acpi-cpufreq? Thomas > If this ACPI device provides more functions, then these should probably > also be added to this driver. > Splitting the OS drivers the same way as BIOS splits up functionality into > ACPI devices is a good idea. > > Could you paste at least the whole ACPI device in which: > #define ASUS_CPUFV_READ_METHOD "CFVG" > #define ASUS_CPUFV_WRITE_METHOD "CFVS" > sit or better point to an acpidump/dsdt output. > > Thomas -- 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/