Subject: Re: [PATCH] convert powermac ide blink to new led infrastructure

From: Johannes Berg <[email-masked]>
Date: Mon, 01 May 2006 10:59:19 +0200

On Mon, 2006-05-01 at 16:56 +1000, Benjamin Herrenschmidt wrote:

> Hrm... you find out the hard way in general ... we'll have to be careful
> with this one, maybe have the PMU driver stop the LED after the device
> suspend dance or do a sysdev with a suspend/resume and make sure that
> any pending LED request is complete. Also, your code isn't testing if
> the PMU request is still in progress before possibly sending another
> one ... that's a bit dangerous (and may cause the LED to get "stuck").
> You can re-use a request once it's complete though. In addition, my PMU
> code was written to minimize spinlock usage in the hot path... There
> might be a way to do the same here.

I don't really understand how the PMU works hence wasn't really sure
what the whole request thing does. Do we get an interrupt when it
completes or something? If so, could I get at that notification via the
request structure?

I'll take a closer look and rework this, I think it's worthwhile even if
it requires some more effort.

johannes