On Fri, 16 Jan 2009, Florian Echtler wrote: > cat /proc/acpi/ibm/thermal > temperatures: 43 37 35 45 50 -128 29 -128 37 46 43 -128 -128 -128 -128 > -128 That 45 next to the 50, and the 46 and 43 near the end tail of -128 are likely going to keep your fan on, yes. That 50 is a probably a battery pack telling us something that we don't know, but since the EC does, it doesn't matter (i.e. if it is to be ignored, the EC will know that and do just that). I asked Lenovo, and they refused to explain it. > However, there's obviously a bit more to this. Yes. > a) when I load the coretemp module and try to read the temperature via > lm-sensors, I get two values around 60 °C, while thinkpad-acpi shows the > above. Same applies to the standard ACPI thermal interface. I have a > total of 13 different thermal measurements.. :-) Heh. The only ones you can somehow figure out without messing with the hardware are coretemp (they're exactly what they should be), and the ACPI TZ ones (read the AML disassembly dump). All the others require that you open your thinkpad and make good use of a can of cold air to locate what sensor changes when you cool each part of the planar card. > b) the really weird part: when I remove the power supply and let the > laptop run on battery, the fan immediately stops! Some minutes later, it Yes, the EC (or BIOS, who knows. Much of the thinkpad firmware is SMM code) changes the fan/thermal control profile based on many things. It also tells ACPI to limit the CPU speed, and other honky things. It all depends on how you configured your BIOS. -- "One disk to rule them all, One disk to find them. One disk to bring them all and in the darkness grind them. In the Land of Redmond where the shadows lie." -- The Silicon Valley Tarot Henrique Holschuh -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
