Date: Sat, 14 Jan 2006 12:39:11 -0800 From: Nate Lawson <nate@root.org> To: Markus Brueffer <markus@brueffer.de> Cc: cvs-src@FreeBSD.org, src-committers@FreeBSD.org, cvs-all@FreeBSD.org Subject: Re: cvs commit: src/sys/dev/acpi_support acpi_ibm.c Message-ID: <43C9616F.1000302@root.org> In-Reply-To: <43C84EEF.6050009@brueffer.de> References: <20060114003924.9E25816A4D1@hub.freebsd.org> <43C84B36.4070000@root.org> <43C84EEF.6050009@brueffer.de>
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Markus Brueffer wrote: > Nate Lawson schrieb: > >>Markus Brueffer wrote: >> >>>markus 2006-01-14 00:39:10 UTC >>> >>> FreeBSD src repository (ports committer) >>> >>> Modified files: >>> sys/dev/acpi_support acpi_ibm.c Log: >>> - Add support for setting the fan control mode to manual or automatic >>> - Add support for adjusting the fan speed if the fan control mode is >>>manual >>> Documentation for the relevant embedded controller register was >>>obtained from >>> http://www.thinkwiki.org/wiki/Patch_for_controlling_fan_speed >>> Tested on: R51 by Fabian Keil >>> T41p by markus >>> Requested by: many >>> Approved by: philip >>> MFC after: 1 week >>> Revision Changes Path >>> 1.10 +55 -3 src/sys/dev/acpi_support/acpi_ibm.c >> >>Thanks for adding support for this but it should be noted that this can >>be very dangerous. If your userland app tries to control the fanspeed >>and dies, your system could overheat. Hopefully, the BIOS will override >>the user settings if the temp gets too high but that is a longshot when >>mucking with things at this low level. > > That's why I didn't add support for it in the first place. The problem > is that especially with the T43 series there seems to be a fan problem. > If it reaches a certain threshold the fan is switched on, but never > switched off regardless how cool the notebook gets. That's probably a bug in acpi_thermal. It needs a thorough debugging anyway. > If the new documentation in acpi_ibm(4) isn't enough, I can add bigger > warning signs: > > dev.acpi_ibm.0.fan > Indicates whether the fan is in automatic (1) or manual (0) mode. > Default is automatic mode. This sysctl should be used with > extreme precaution, since disabling automatic fan control might > overheat the ThinkPad and lead to permanent damage if the > > For obvious reasons I haven't tested if the BIOS overrides the user > settings if the temp gets too high :) That seems good. I didn't see the man page update before I replied. -- Nate
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