Re: [PATCH v3] xhci: Prevent runtime suspend on Etron EJ168

[Kai-Heng Feng]

> On Sep 29, 2020, at 05:42, Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx> wrote:
> 
> On 28.9.2020 12.10, Kai-Heng Feng wrote:
>> 
>> 
>>> On Jun 8, 2020, at 11:56, Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx> wrote:
>>> 
>>> 
>>> 
>>>> On May 5, 2020, at 01:16, Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx> wrote:
>>>> 
>>>> Etron EJ168 USB 3.0 Host Controller stops working after S3, if it was
>>>> runtime suspended previously:
>>>> [  370.080359] pci 0000:02:00.0: can't change power state from D3cold to D0 (config space inaccessible)
>>>> [  370.080477] xhci_hcd 0000:04:00.0: can't change power state from D3cold to D0 (config space inaccessible)
>>>> [  370.080532] pcieport 0000:00:1c.0: DPC: containment event, status:0x1f05 source:0x0200
>>>> [  370.080533] pcieport 0000:00:1c.0: DPC: ERR_FATAL detected
>>>> [  370.080536] xhci_hcd 0000:04:00.0: can't change power state from D3hot to D0 (config space inaccessible)
>>>> [  370.080552] xhci_hcd 0000:04:00.0: AER: can't recover (no error_detected callback)
>>>> [  370.080566] usb usb3: root hub lost power or was reset
>>>> [  370.080566] usb usb4: root hub lost power or was reset
>>>> [  370.080572] xhci_hcd 0000:04:00.0: Host halt failed, -19
>>>> [  370.080574] xhci_hcd 0000:04:00.0: Host not accessible, reset failed.
>>>> [  370.080575] xhci_hcd 0000:04:00.0: PCI post-resume error -19!
>>>> [  370.080586] xhci_hcd 0000:04:00.0: HC died; cleaning up
>>>> 
>>>> This can be fixed by not runtime suspend the controller at all.
>>>> 
>>>> So disable runtime suspend for EJ168 xHCI device.
>>>> 
>>>> Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>
>>> 
>>> A gentle ping...
>> 
>> Another gentle ping...
> 
> Thanks, somehow I didn't notice this earlier.
> 
> Was the rootcause ever investigated?
> Preventing runtime suspend looks like a quick fix to get rid of the issue, but 
> possibly just hides some other underlying power management problem

I tried different angles but didn't find any useful solution.

Eventually I found out that the device stays at D0 under Windows, so this is the approach I take.

Kai-Heng

> 
> -Mathias