Date: Wed, 21 Dec 2005 14:26:18 +0100 From: Fredrik Lindberg <fli+freebsd-current@shapeshifter.se> To: Tobias Roth <roth@iam.unibe.ch> Cc: current@freebsd.org Subject: Re: IBM Thinkpad Fan Control (acpi_ibm) Message-ID: <43A957FA.8090005@shapeshifter.se> In-Reply-To: <20051221100954.GB24363@droopy.unibe.ch>
index | next in thread | previous in thread | raw e-mail
Tobias Roth wrote: > Hi > > With acpi_ibm.ko, I can monitor fan speed, thermal sensors and do > many other nice things. However, my Thinkpad (a T43p) has an awfully > noisy fan, that, once the notebook reaches its standard working > temperature (around 45 deg C), turns on and never stops again. > > The generally accepted solution his to manually lower the fan speed > and live with the higher temperatures, which will still be in an > acceptable range even with slow running fans. The discussion and a > utility for Windows can be found here [1], and a linux tool is > described here [2]. > > Now my question. Since acpi_ibm.ko can already read temperature > sensors and fan speed, would it be feasable to teach it to control > fan speed as well? Is anyone working on it already? Or can someone > outline the steps that have to be taken so I can take a look and > see if I can do it myself? > > thanks, t. I don't know if somebody is working on it, but it shouldn't be too hard to add it to acpi_ibm. Just parse the relevant bits from the linux patch and add a new sysctl method for fan speed in the acpi_ibm_sysctl_set() function in the file sys/dev/acpi_support/acpi_ibm.c I did this a while ago for but for fan enable/disable, but that is really useless because the only thing you can accomplish with the fan off is a fried laptop (although, it will be quiet :)). It's probably quite dangerous to mess with the fan speed too, because even if the fan is running at low speed you risk overheating your system. Fredrik Lindberghome | help
Want to link to this message? Use this
URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?43A957FA.8090005>