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Date:   Thu, 13 May 2021 10:41:36 -0400
From:   Alan Stern <stern@rowland.harvard.edu>
To:     Chris Chiu <chris.chiu@canonical.com>
Cc:     Greg KH <gregkh@linuxfoundation.org>, m.v.b@runbox.com,
        hadess@hadess.net, linux-usb@vger.kernel.org,
        Linux Kernel <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2 1/2] USB: reset-resume the device when PORT_SUSPEND is
 set but timeout
Message-ID: <20210513144136.GF967812@rowland.harvard.edu>
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On Thu, May 13, 2021 at 12:21:52PM +0800, Chris Chiu wrote:
> On Wed, May 12, 2021 at 11:04 PM Alan Stern <stern@rowland.harvard.edu> wrote:
> >
> > For testing purposes, set status to 0 and jump to a new goto label in
> > the "else" branch.  In other words, treat it as if the suspend really
> > had worked and go back to the successful pathway.  Try this out and see
> > if it fixes the problem.
> >
> > If it does then the reset-resume isn't needed.  If it doesn't, post your
> > patch again, and mention in the patch description that testing shows the
> > reset-resume really is necessary.
> >
> > Alan Stern
> 
> Thanks for the suggestion. I revised the patch to create a new goto
> label in the "else" branch and clear the status to zero if the port is
> really suspended. It fixed the problem in my 100 time suspend/resume
> test. I will send v3 patch w/ the modification.

Great!  This is a much better solution.

Alan Stern