The reason for this error is that the root hub wasn't already
suspended. Was there a USB device plugged into that controller?
Two days ago I ran 2.6.27-rc6 plus gregkh-all-2.6.27-rc6.patch from
http://www.kernel.org/pub/linux/kernel/people/gregkh/gregkh-2.6/
on my laptop, and it suspended with no problem. Can you try the same
kernel?
If you still run into problems, post more of the dmesg log (with
CONFIG_USB_DEBUG enabled, of course!).
Alan Stern
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