[ltp] Temperature sensors on X201s

Henrique de Moraes Holschuh linux-thinkpad@linux-thinkpad.org
Wed, 5 May 2010 23:54:28 -0300

On Wed, 05 May 2010, Stefan Monnier wrote:
> - cat /proc/acpi/ibm/thermal gives me just:
>     temperatures:   43 0 0 0 0 0 0 0
>   now 43� is fine, but how come there's only 1 value there.  Are there

Pester Lenovo in their forums about it...  Either there are no sensors
anymore, or they decided to hide them because of the windows fan-control
crowd or some other random reason.

Note that the chipsets, memory (at least on servers), and a lot of other
stuff has thermal sensors embedded nowadays.  It is just that getting to
them is often quite hard.

There is a firmware thermal alarm now, though, so at least you will get
an alert if things are about to catch fire.  Useless for any sort of
runtime tunning...

> - /sys/class/power_supply/BAT0/current_now seems to sometimes report
>   power rather than current (i.e. sometimes it's 1000 times
>   /sys/devices/platform/smapi/BAT0/current_avg and sometimes it's 1000
>   times /sys/devices/platform/smapi/BAT0/power_avg).  Not clear when it
>   changes from one to the other.  powertop also seems confused about it
>   (when current_now correctly gives current, powertop seems to interpret
>   it as power).

Report this as a bug in bugzilla.kernel.org or the distro, please.  But
make sure you're using the very latest firmware, first.

> - Xorg only works with KMS.  Without it, it crashes the whole system
>   (black screen, typically with blinking caps-lock led, tho not always).

Report it through the distro, I think.  KMS pratically requires
bleeding-edge backports in the kernel and userspace...

> - hibernate tends to corrupt some part of the memory (I have the same
>   thing on my MSI Wind, where disabling KMS works around the problem).

Yikes.  Report to distro.

  "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