On Thu, Nov 29, 2007 at 06:05:18PM -0500, Alan Stern wrote:
> On Thu, 29 Nov 2007, Sarah Sharp wrote:
> 
> > It takes care of half the problem.  After adding a reset-resume quirk,
> > suspend works fine, but the device still breaks on hibernate (or a
> > suspend that causes a power loss).  The log file is attached from
> > hibernating the machine, seeing that the device registered as a low
> > speed rather than a full speed device, and then removing and replugging
> > in the device.
> 
> That's weird.  From the device's point of view there shouldn't be any 
> difference between a hibernation with loss of power and a normal 
> unplug/replug cycle.  Maybe there wasn't actually a power loss -- if 
> the USB host controller was reinitialized by the BIOS the kernel 
> wouldn't be able to tell the difference.

After doing some additional testing, I figured out that the device
handles hibernate correctly *if* it's not getting power through the
serial cable.  If I leave the serial end connected to another usb to
serial device (which is attached to another laptop) and hibernate,
the device comes back as low speed.  If I disconnect the serial end,
the device comes back as high speed.

Suspend with no power loss works fine in either case, as long as the
device gets a reset resume.  Unplugging/replugging the device in works
every time.  This is just a wacky device.

Sarah
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