On Tue, 8 Mar 2005, Adam Belay wrote: > The idea here is that if a device could be put into a lower state in which > it isn't operational, but still maintains configuration, then we could just > use "close" and "open". For complete poweroffs we could do: > > "close" -> "stop" and... "start" -> "open". > > A power state has the following characteristics: > Is the device operational? > Is the context of the device maintained? > Is the configuration of the device maintained? > > "start" and "stop" handle configuration, "open" and "close" handle context. You would end up imposing your own three-layer set of power states on devices for which it might not be appropriate. Many devices would only support one or two of those layers; the rest would be wasted. Other devices might have even more finely-grained power distinctions. I think it's better to keep the central PM model as simple as possible and leave complicating details to the individual drivers and to userspace. Alan Stern