From: Oliver Neukum <oliver@neukum.org>
To: "Justin P. Mattock" <justinmattock@gmail.com>
Subject: Re: root hub lost power or was reset
Date: Thu, 3 Dec 2009 09:33:47 +0100
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Cc: Robert Hancock <hancockrwd@gmail.com>,
       "Linux-usb" <linux-usb@vger.kernel.org>,
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Am Donnerstag, 3. Dezember 2009 01:58:46 schrieb Justin P. Mattock:
> >> Now looking at dmesg I see:
> >>
> >> [ 413.551845] uhci_hcd 0000:00:1d.0: PCI INT A -> GSI 23 (level, low)
> >> -> IRQ 23
> >> [ 413.551855] uhci_hcd 0000:00:1d.0: setting latency timer to 64
> >> [ 413.551887] usb usb2: root hub lost power or was reset
> >
> > Is that unexpected? It seems reasonable to me..
> 
> honestly I can't remember seeing this or not.
> if this is normal then I'll leave it as is.

This happens if your system cuts power to USB during S2.
It trades a small reduction in energy consumption against
losing support for all devices whose drivers don't support
reset_resume().

This is a design feature of your system or BIOS, not a bug.

	Regards
		Oliver
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