Re: [stable] pcmcia resume 60 second hang. Re: [patch 00/69] -stable review

[Greg KH <greg@kroah.com>]

On Mon, May 28, 2007 at 09:53:50AM -0700, Linus Torvalds wrote:
> 
> Before we suspend a device, we call the subsystem that that device has 
> been registered with. Ie, we have code like this:
> 
> 	if (dev->class && dev->class->suspend)
> 		error = dev->class->suspend(dev, state);
> 
> which was very much designed so that individual devices wouldn't have to 
> always know - if the upper layer devices for that class can handle these 
> things, they should.
> 
> Do people actually _do_ this, right now? No. But we do actually have the 
> infrastructure, and I think we have one or two classes that actually do 
> use it (at least the "rfkill_class" has a suspend member, dunno how well 
> this model actually works).
> 
> I think Greg had some patches to make network drivers use this, for 
> example. Network drivers right now all end up doing stuff that really 
> doesn't belong in the driver at all when they suspend, and the 
> infrastructure _should_ just do it for them (ie do all the _network_ 
> related stuff, as opposed to the actual hardware-related stuff).

Yes, I started to work on it, as it is the correct thing to do, but got
sidetracked, sorry :(

> (Examples of things that we probably _should_ do for network devices on a 
> class level:
> 
> 	suspend:
> 		netif_poll_disable()
> 		if (netif_running(dev))
> 			dev->stop(dev);
> 
> 	resume:
> 		if (netif_running(dev))
> 			dev->start(dev);
> 		netif_poll_enable(dev);
> 
> or something similar).

I'll try to hack something together later this week along this line and
see how it works...

thanks,

greg k-h
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