Re: Problems porting asus_acpi to LED subsystem

[Pavel Machek <pavel@ucw.cz>]

On Tue 2006-07-04 10:50:22, Pavel Machek wrote:
> Hi!
> 
> > Summary:
> > 
> > I'm trying to link asus_acpi into the LED subsystem.  My set_brightness
> > callback evaluates an ACPI method to set the LED state.  It works fine
> > manually changing the brightness, but when the callback is called by a
> > timer (using the timer or ide-disk triggers), it eventually causes an
> > Oops.  I can post my code or the Oops if it would help.  I'm new at
> > kernel coding, and I'm not on the list, so please CC me on any reply.
> > Sorry if this isn't appropriate on the list.
> 
> I _guess_ the LED subsystem can be called from interrupt, and ACPI
> does not like that. So you probably need to use workqueue to defer
> setting a bit.

I guess 

	       schedule_delayed_work(&sharpsl_bat, msecs_to_jiffies(500));

is one of the ways how to move to process context from potentially
interrupt context. see sharpsl_pm.c for example usage.

								Pavel

-- 
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(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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