Re: [lm-sensors] [PATCH] therm_adt746x: Record pwm invert bit at module load time

From: Jean Delvare
Date: Fri Dec 04 2009 - 03:44:16 EST


On Fri, 04 Dec 2009 13:20:11 +1100, Benjamin Herrenschmidt wrote:
> On Mon, 2009-11-30 at 15:47 -0800, Darrick J. Wong wrote:
> > In commit 0512a9a8e277a9de2820211eef964473b714ae65, we unilaterally zero the
> > "pwm invert" bit in the fan behavior configuration register. On my PowerBook
> > G4, this results in the fans going to full speed at low temperature and
> > shutting off at high temperature because the pwm invert bit is supposed to be
> > set.
> >
> > Therefore, record the pwm invert bit at driver load time, and write the bit
> > into the fan behavior control register. This restores correct behavior on my
> > PBG4 and should work around the bit being set to the wrong value after
> > suspend/resume (which is what the original patch was trying to fix). It also
> > fixes a minor omission where the pwm invert bit correction is NOT performed
> > when switching into automatic mode.
>
> Thanks, I'll apply.

This is a pretty serious bug, please make sure to send the fix to the
stable team for kernels 2.6.31 and 2.6.32.

--
Jean Delvare
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