On Fri, 12 Jan 2007, David Brownell wrote:
> On Friday 12 January 2007 11:11 am, Alan Stern wrote:
> > On Fri, 12 Jan 2007, Vasudevan S wrote:
> >
>
> > > PCI: Enabling device 0000:00:1d.7 (0000 -> 0002)
> > > usb usb1: root hub lost power or was reset
> > > usbdev1.2_ep00: PM: resume from 0, parent 1-1 still 1
> > >
> > > [followed by the similar usb messages, but for different hubs]
> > > "
> >
> > Those messages are normal. They indicate that the USB controllers weren't
> > powered while the machine was shut off.
>
> The "root hub lost power" etc is normal.
>
> The other message indicates that a child device (for ep0) was resumed
> before the parent was, or that at least the driver model records for
> that linkage became corrupt. No, it's not normal to violate either kind
> of system integrity constraint ...
It's not corruption. The "resume from 0, parent 1-1 still 1" message is
there for two reasons:
1. usbdev1.2_ep00 and its siblings are "pseudo-devices" representing
USB endpoints. The driver for them doesn't have a suspend or
a resume method (the idea doesn't even make sense) so the PM core
sees their power_state.event is always 0.
2. Loss of power to the root hub means that the 1-1 device fails
to resume (-ENODEV, the device is gone). Hence its
power_state.event value never gets set back to 0.
The reasons and the message will all go away once power_state is removed.
Alan Stern
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