Re: ordering of suspend/resume for devices. any clues, anyone?

[Luke Kenneth Casson Leighton <lkcl@lkcl.net>]

heya pavel,

thanks for the tip.  as it turns out, a function table was hacked-n
that back-link from the w100fb framebuffer resume function into the
LCD code.

in this way, it is possible to call functions in the LCD module
doing GPIO to start the power-up sequence required for the
LCD and backlight, wait a few ms, initialise the video chip
(in the w100fb code), then call _another_ set of functions in
the LCD module to finish off the initialisation.

not pretty, but there you go.

l.

On Wed, Dec 21, 2005 at 11:21:09AM +0100, Pavel Machek wrote:
> Hi!
> 
> > [hi, please kindly cc me direct as i am deliberately subscribed with
> > settings to not receive posts from this list, but if that is inconvenient
> > for you to cc me, don't worry i can always look up the archives
> > to keep track of replies, thank you.]
> > 
> > http://handhelds.org/moin/moin.cgi/BlueAngel
> > 
> > works.
> > 
> > am seeking some advice regarding power management - specifically
> > the ordering of devices "resume" functions being called.
> > 
> > we have an LCD, and an ATI chip.  switching on the LCD powers up
> > the ATI chip.
> > 
> > unfortunately, resume calls the ATI device initialisation
> > _before_ the LCD resume initialisation.  the ATI chip's
> > initialisation fails - naturally - because it's not even
> > powered up.
> 
> I'd say "make LCD system/platform device". That will init it first,
> shut it down last.
> 							Pavel
> 
> -- 
> Thanks, Sharp!

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