suspend/resume timings

Jim Gettys jg at
Tue Apr 3 12:14:44 EDT 2007

On Tue, 2007-04-03 at 08:52 -0700, Hal Murray wrote:
> > The keyboard is left powered up during suspend: we shouldn't need to
> > reset it at all (except on power up).  This is so you can touch a key
> > or the keypad and get the CPU back instanty. 
> I think "instantly" is misleading.  You need power so you can get it back at 
> all.  If there is no power to the keyboard there is no way for the keyboard 
> to generate a wakeup signal.
> What's the plan for USB?  Currently it gets powered off.  Is that the long 
> term plan?  If so, we can't wakeup the CPU from USB gizmos.

That's the plan for the most power savings (e.g. ebook mode).  The
wireless has its own out of band signal to the EC enabling it to wake up
the CPU.

> USB is polled from the host.  (There isn't a separate interrupt wire.)  Does 
> the XO have special hardware to do that or does the CPU need to poke the 
> hardware occasionally?
> What's the short/intermediate plan for people using ssh over a USB Ethernet 
> dongle?

Should just work (modulo this instant, NetworkManager, if it sees a
mesh, will prefer it over a wired connector: dcbw is looking into that).

But as you've got one machine only, I expect you should be able to plug
in USB ethernet and go to town.
Jim Gettys
One Laptop Per Child

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