Re: [Regression] USB wakeup problem on Toshiba Portege R500

From: Rafael J. Wysocki
Date: Thu Jan 08 2009 - 14:55:36 EST


On Thursday 08 January 2009, Frans Pop wrote:
> Rafael J. Wysocki wrote:
> > On Thursday 08 January 2009, Oliver Neukum wrote:
> >> Am Thursday 08 January 2009 17:36:12 schrieb Rafael J. Wysocki:
> >> You are making a very persuasive argument for reverting it.
> >> But what about laptops that only have a USB keyboard?
> >
> > Well, up to and including 2.6.28 they needed to echo 'enable' to the USB
> > controllers' /sys/devices/.../power/wakeup files, so if the patch is
> > reverted, they won't be worse off than they were day before
> > yesterday. :-)
> >
> > Perhaps we can choose the default depending on whether or not any HID
> > devices are attached to given controller?
>
> Is "resume on keyboard activity" really all that needed? Both my laptops
> and my desktop resume fine after pressing the power button.
>
> Also consider the following cases:
> - laptop has been suspended with external USB mouse connected
> - mouse is moved (accidentally or because it is in the way of a coffee
> cup)
> - mouse cable is removed before putting the laptop in a bag for
> transport
> - laptop is in docking station with USB mouse/kbd connected to that
> - again, mouse gets moved for some reason
> - laptop is undocked while suspended
> - or the reverse: laptop gets docked

One more case (a real-life example actually):
- There is a USB wireless mouse attached to the box while suspending and the
mouse is powered off by pressing a button on it. The mouse's radio receiver
remains in a USB port on the box. Now, if the mouse is powered off again,
the box will resume. What if that happens accidentally while the box is
being carried in a backpack?

> IMO it is not desirable that the system gets resumed as a result of any of
> those actions. I'm not complete sure that it would in all those cases,
> but have they been considered?
>
> And in general I've always been in favor of things only happening
> automagically if I've explicitly asked for that, and not by default.

I have to say I agree.

Thanks,
Rafael
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