[ltp] [patch 11/12][2.6.18] ibm-acpi: workaround for EC 0x2f initialization bug

[Henrique de Moraes Holschuh]

On Tue, 24 Oct 2006, Shem Multinymous wrote:
> On 10/24/06, Henrique de Moraes Holschuh <hmh@hmh.eng.br> wrote:
> >> How about this conservative but more useful variant?
> >> If the fan level register reads 0x07, don't touch it (it's either a
> >> DSDT emergency, or the boot bug, or a someone who's doing manual
> >> control anyway and can run "level auto" instead).
> >> Otherwise set it to 0x80.
> >
> >I could make it "if it is zero, set it to 0x80, otherwise leave it alone",
> 
> No, that could leave it forced to (say) level 1.
> I'm thinking of "enable" as "Hi! I'm a legacy app or a naive user and
> don't know what I'm doing. Please make sure my CPU doesn't fry but
> don't make a mess about it." My variant seems to answer this
> reasonably.

Setting it to level 4 or auto is the answer to that.  So, it would become:

1. If level is 7, leave it alone and exit.
2. Otherwise, if auto is supported, set it to auto and exit.
3. Otherwise, if level is less than four, set it to four.

This is more in line with "enable" being "set the fan to something
sensible", for a thermal-blind way definition of sensible.

I *still* don't like the thermal-blind part.

-- 
  "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