Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
MIME-Version: 1.0
References: <20230411083145.2214105-1-hhhuuu@google.com> <ce727a7b-6954-4e4d-85c7-f91011b87108@rowland.harvard.edu>
In-Reply-To: <ce727a7b-6954-4e4d-85c7-f91011b87108@rowland.harvard.edu>
From:   Jimmy Hu <hhhuuu@google.com>
Date:   Wed, 12 Apr 2023 09:55:02 +0800
Message-ID: <CAJh=zj+sVjmLAnY8pXWKbuhVsYStv3Ei5C6KqyugwURd8B-0wA@mail.gmail.com>
Subject: Re: [PATCH] usb: core: hub: Disable autosuspend for VIA VL813 USB3.0 hub
To:     Alan Stern <stern@rowland.harvard.edu>
Cc:     gregkh@linuxfoundation.org, badhri@google.com,
        linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org,
        stable@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
Precedence: bulk

On Tue, Apr 11, 2023 at 9:55=E2=80=AFPM Alan Stern <stern@rowland.harvard.e=
du> wrote:
>
> On Tue, Apr 11, 2023 at 08:31:45AM +0000, Jimmy Hu wrote:
> > The VIA VL813 USB3.0 hub appears to have an issue with autosuspend and
> > detecting USB3 devices. This can be reproduced by connecting a USB3
> > device to the hub after the hub enters autosuspend mode.
> >
> > //connect the hub
> > [  106.854204] usb 2-1: new SuperSpeed Gen 1 USB device number 2 using =
xhci-hcd
> > [  107.084993] usb 2-1: New USB device found, idVendor=3D2109, idProduc=
t=3D0813, bcdDevice=3D90.15
> > [  107.094520] usb 2-1: New USB device strings: Mfr=3D1, Product=3D2, S=
erialNumber=3D0
> > [  107.111836] usb 2-1: Product: USB3.0 Hub
> > [  107.116835] usb 2-1: Manufacturer: VIA Labs, Inc.
> > [  107.314230] hub 2-1:1.0: USB hub found
> > [  107.321356] hub 2-1:1.0: 4 ports detected
> >
> > //the hub enters autosuspend mode
> > [  107.738873] hub 2-1:1.0: hub_suspend
> > [  107.922097] usb 2-1: usb auto-suspend, wakeup 1
> >
> > //connect a USB3 device
> > [  133.120060] usb 2-1: usb wakeup-resume
> > [  133.160033] usb 2-1: Waited 0ms for CONNECT
> > [  133.165423] usb 2-1: finish resume
> > [  133.176919] hub 2-1:1.0: hub_resume
> > [  133.188026] usb 2-1-port3: status 0263 change 0041
> > [  133.323585] hub 2-1:1.0: state 7 ports 4 chg 0008 evt 0008
> > [  133.342423] usb 2-1-port3: link state change
> > [  133.358154] usb 2-1-port3: status 0263, change 0040, 5.0 Gb/s
>
> This status value indicates that the port is in the U3 suspend state.
> Maybe the port needs to be put back into U0 before it can be reset.
>
> > [  133.875150] usb 2-1-port3: not reset yet, waiting 10ms
> > [  133.895502] usb 2-1-port3: not reset yet, waiting 10ms
> > [  133.918239] usb 2-1-port3: not reset yet, waiting 200ms
> > [  134.139529] usb 2-1-port3: not reset yet, waiting 200ms
> > [  134.365296] usb 2-1-port3: not reset yet, waiting 200ms
> > [  134.590185] usb 2-1-port3: not reset yet, waiting 200ms
> > [  134.641330] hub 2-1:1.0: state 7 ports 4 chg 0000 evt 0008
> > [  134.658880] hub 2-1:1.0: hub_suspend
> > [  134.792908] usb 2-1: usb auto-suspend, wakeup 1
> >
> > Disabling autosuspend for this hub resolves the issue.
>
> It may be possible to fix the problem.  You should try that before
> giving up.
>
> Alan Stern

[  133.120060] usb 2-1: usb wakeup-resume
[  133.160033] usb 2-1: Waited 0ms for CONNECT
[  133.165423] usb 2-1: finish resume
[  133.176919] hub 2-1:1.0: hub_resume
When a USB3 device is connected to the hub,  it did finish the resume
and should be put back into U0, but it seems to have failed.