From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932733AbYBFXSk (ORCPT ); Wed, 6 Feb 2008 18:18:40 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1763582AbYBFXQf (ORCPT ); Wed, 6 Feb 2008 18:16:35 -0500 Received: from pentafluge.infradead.org ([213.146.154.40]:36268 "EHLO pentafluge.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1763459AbYBFXQd (ORCPT ); Wed, 6 Feb 2008 18:16:33 -0500 Date: Wed, 6 Feb 2008 15:07:02 -0800 From: Greg KH To: Roel Kluin <12o3l@tiscali.nl> Cc: Henrique de Moraes Holschuh , Roland Dreier , len.brown@intel.com, ibm-acpi-devel@lists.sourceforge.net, linux-acpi@vger.kernel.org, lkml , stable@kernel.org Subject: Re: [PATCH][drivers/misc/thinkpad_acpi.c] duplicate test if (level & TP_EC_FAN_FULLSPEED) Message-ID: <20080206230702.GA12395@kroah.com> References: <47A78CBB.2090401@tiscali.nl> <47A79EC8.6060700@tiscali.nl> <20080205050504.GB30670@khazad-dum.debian.net> <47A81FAE.2090709@tiscali.nl> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <47A81FAE.2090709@tiscali.nl> User-Agent: Mutt/1.5.16 (2007-06-09) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Feb 05, 2008 at 09:34:54AM +0100, Roel Kluin wrote: > Henrique de Moraes Holschuh wrote: > > On Tue, 05 Feb 2008, Roel Kluin wrote: > >> Roland Dreier wrote: > >>> > /* safety net should the EC not support AUTO > >>> > * or FULLSPEED mode bits and just ignore them */ > >>> > if (level & TP_EC_FAN_FULLSPEED) > >>> > level |= 7; /* safety min speed 7 */ > >>> > else if (level & TP_EC_FAN_FULLSPEED) > >>> > level |= 4; /* safety min speed 4 */ > >>> > > >>> > Note the duplicate test 'if (level & TP_EC_FAN_FULLSPEED)'. should > >>> > this be replaced by > >>> > >>> Actually I suspect one of the two tests should be against TP_EC_FAN_AUTO > >>> (based on the comment). > >> Thanks Roland, for your info > >> > >> based on the comments in commit eaa7571b2d1a08873e4bdd8e6db3431df61cd9ad, > >> I think this should be modified like below: > >> > >> ACPI: thinkpad-acpi: add a safety net for TPEC fan control mode > >> The Linux ThinkPad community is not positive that all ThinkPads that do > >> HFSP EC fan control do implement full-speed and auto modes, some of the > >> earlier ones supporting HFSP might not. > >> > >> If the EC ignores the AUTO or FULL-SPEED bits, it will pay attention to the > >> lower three bits that set the fan level. And as thinkpad-acpi was leaving > >> these set to zero, it would stop(!) the fan, which is Not A Good Thing. > >> So, as a safety net, we now make sure to also set the fan level part of the > >> HFSP register to speed 7 for full-speed, and a minimum of speed 4 for auto > >> mode. > >> -- > >> second TP_EC_FAN_FULLSPEED should be P_EC_FAN_AUTO > >> > >> > >> Signed-off-by: Roel Kluin <12o3l@tiscali.nl> > >> --- > >> diff --git a/drivers/misc/thinkpad_acpi.c b/drivers/misc/thinkpad_acpi.c > >> index cf56647..3c323fe 100644 > >> --- a/drivers/misc/thinkpad_acpi.c > >> +++ b/drivers/misc/thinkpad_acpi.c > >> @@ -4138,7 +4138,7 @@ static int fan_set_level(int level) > >> * or FULLSPEED mode bits and just ignore them */ > >> if (level & TP_EC_FAN_FULLSPEED) > >> level |= 7; /* safety min speed 7 */ > >> - else if (level & TP_EC_FAN_FULLSPEED) > >> + else if (level & TP_EC_FAN_AUTO) > >> level |= 4; /* safety min speed 4 */ > >> > >> if (!acpi_ec_write(fan_status_offset, level)) > > > > ACK. This needs to be sent to stable as well. I think both 2.6.22 and > > 2.6.23 need this patch. > > > > CC stable@kernel.org Please send us a real copy of the patch, when it goes into Linus's tree, so we know what to apply, and that it is safe to do so. thanks, greg k-h