add powerbutton and lid platform devices

[David Brownell]

On Monday 09 July 2007, Jordan Crouse wrote:

> I agree that the default setting for the power button should be to 
> wake up, but I don't know about the lid.  Imagine a scenario where somebody
> manually puts the machine to sleep and then shuts the lid.  You wouldn't want
> the machine to turn back on when you lifted it.

I wouldn't want "echo mem > /sys/power/state" to
automagically cause the lid to act strangely...


> Lid behavior is so policy  
> driven, I think we should leave it off by default, and let the power manager
> decide what to do.

What's this "power manager" component?

This policy is easily set through sysfs.  It doesn't need a new
component to make that decision.

- Dave