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Date:   Thu, 17 Aug 2023 10:22:06 -0400
From:   Alan Stern <stern@rowland.harvard.edu>
To:     Kai-Heng Feng <kai.heng.feng@canonical.com>
Cc:     mathias.nyman@intel.com,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] xhci: Disable connect, disconnect and over-current
 wakeup on system suspend
Message-ID: <59898e32-f2ea-4df7-947b-3d74835ff9b7@rowland.harvard.edu>
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 <cab8a29b-816c-41c7-8d2a-418f787e406e@rowland.harvard.edu>
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On Thu, Aug 17, 2023 at 10:07:37AM -0400, Alan Stern wrote:
> On Thu, Aug 17, 2023 at 05:33:05PM +0800, Kai-Heng Feng wrote:
> > HP ProOne 440 G10 AIO sometimes cannot suspend as xHCI wakes up the
> > system:
> > [  445.814574] hub 2-0:1.0: hub_suspend
> > [  445.814652] usb usb2: bus suspend, wakeup 0
> > [  445.824629] xhci_hcd 0000:00:14.0: Port change event, 1-11, id 11, portsc: 0x202a0
> 
> What is the meaning of the 0x202a0 bits?  What caused this wakeup?

And more to the point, given that the previous line says "wakeup 0", why 
should any port change event cause a wakeup?

Alan Stern