Re: Zaurus suspend saga

From: Pavel Machek
Date: Mon Sep 07 2009 - 07:35:27 EST


> > fatal reads invalid values -- -108 -- probably because spi is not ready?
> >
> > is spi suspend/resume required? yes.; and yes spi is resumed too late
> > in the sequence. Or perhaps fatal battery check is way too early.
> >
> > Could someone confirm that simply removing sharpsl_fatal_check() fixes
> > zaurus suspend on 2.6.31?
> Sadly lack of time means I've lost track of the Zaurus kernels but this
> sounds like all accesses to the SSP buses now go through the SPI layer
> and when it was converted nobody thought about the impact this would
> have on the Zaurus charger code.

Unfortunately... Do you have any idea when this conversion took place?

> If suspend/resume is broken in this way, it also means the charger code
> is also likely to be totally broken/malfunctioning since it won't be
> able to read from the ADC either.

Yes. Seems like low-level zaurus code is FUBAR.

> Either:
> a) Someone steps up and finds a way to partially resume the kernel so
> the "offline" charging code can work and access SPI

> b) We find some other way to allow the SPI interface to be accessed by
> the charger code without resuming the whole kernel (the way it used to
> work)

Doing that in a hacky way should be rather easy... just calling spi
resume manually. But...

> c) We rip the whole thing out and stop supporting "offline" charging.

How much faster is offline charge, compared to online charging? I have
impression that online charging basically does not charge anything...

> I'd hate to see c) happen but I doubt I'm going to find time to rewrite
> that code any time soon and nobody else even seems to have grasped how
> deep this problem really is :(.

Well, I have a bit of time now and then...
(cesky, pictures)
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