Most recent kernel where this bug did not occur: Distribution: Fedora Core 5 Hardware Environment: Compaq Presario Software Environment: bash Problem Description: acpi reports 0 C temperature on Compaq Presario 5201CA Steps to reproduce: cat /proc/acpi/thermal_zone/THRM/temperature
Please, submit the 'dmesg' and 'acpidump' commands output. PS: you can do it for either Bug #7140 or #7139 only :)
Created attachment 8999 [details] dmesg output Note that this is not a kernel.org kernel and I have the ATI kernel modules loaded.
Created attachment 9000 [details] acpidump output Same kernel situation as the previous attachment.
Created attachment 9001 [details] DSDT debug patch The temperature being evaluated from 'THEM' field in EC device. Could you implement this patch to see the actual values of this field? (for instructions you could refer to http://acpi.sourceforge.net/download.html http://forums.gentoo.org/viewtopic.php?t=122145 ) Also, does it make any difference if you disable proprietary drivers, use vanilla kernel, or both?
To enable debug output boot with 'acpi_debug=0xffffffff'.
Created attachment 9008 [details] dmesg output Thanks for the help. I compiled a vanilla kernel.org 2.6.17.13 kernel (with no changes to default options except CONFIG_ACPI_DEBUG=y) and booted without loading the ATI modules and the TMP values were 0s as you can see in the attached dmesg.out.
Created attachment 9009 [details] corrected dmesg.out The previous attachment was an accidentally concatenated dmesg.out (i.e., the first few lines shouldn't have been there).
Well, it looks like hardware/BIOS issue for me, since thermal module is able to aquire temperature, and it's the same as the value returned from EC field. The reason could be wrong EC memory mapping (defined in DSDT) or broken sensor. You could try to get the latest BIOS update from HP site to see if it'll fix the problem.