On Fri, 28 Jul 2017, Zdenek Kabelac wrote:
> Dne 28.7.2017 v 20:33 Alan Stern napsal(a):
> > On Thu, 27 Jul 2017, Zdenek Kabelac wrote:
> >
> >>> Zdenek, you check this explanation by commenting out these last two
> >>> lines at the end of hub_port_connect() in drivers/usb/core/hub.c:
> >>>
> >>> if (hcd->driver->relinquish_port && !hub->hdev->parent)
> >>> hcd->driver->relinquish_port(hcd, port1);
> >>>
> >>> That should prevent the connection from being handed over to the UHCI
> >>> companion, allowing the device to operate at high speed.
> >>>
> >>
> >> Hi
> >>
> >> Yep - seems this helped - I've dropped revert and commented those 2 lines
> >> and I've used the very same kernel - and speed was all good:
> >>
> >> usb 2-2: new high-speed USB device number 2 using ehci-pci
> >> usb 2-2: new high-speed USB device number 3 using ehci-pci
> >> usb 2-2: New USB device found, idVendor=1058, idProduct=10a8
> >> usb 2-2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
> >>
> >>
> >> So while I'm not sure if this is final fix for USB - this solution surely
> >> solved my WD Element disk attachment issue.
> >
> > Great! Here's a real patch to test; I think this will be acceptable if
> > it fixes your problem.
> >
> > Alan Stern
> >
> >
> >
> > Index: usb-4.x/drivers/usb/core/hub.c
> > ===================================================================
> > --- usb-4.x.orig/drivers/usb/core/hub.c
> > +++ usb-4.x/drivers/usb/core/hub.c
> > @@ -4934,9 +4934,10 @@ loop:
> >
> > done:
> > hub_port_disable(hub, port1, 1);
> > - if (hcd->driver->relinquish_port && !hub->hdev->parent)
> > - hcd->driver->relinquish_port(hcd, port1);
> > -
> > + if (hcd->driver->relinquish_port && !hub->hdev->parent) {
> > + if (status != -ENOTCONN && status != -ENODEV)
> > + hcd->driver->relinquish_port(hcd, port1);
> > + }
> > }
> >
> > /* Handle physical or logical connection change events.
> >
>
>
> Hi
>
> Yep - still good speed - however compilation reported this Warning:
>
> drivers/usb/core/hub.c:4933:37: warning: ‘status’ may be used uninitialized in
> this function [-Wmaybe-uninitialized]
> if (status != -ENOTCONN && status != -ENODEV)
> drivers/usb/core/hub.c:4728:6: note: ‘status’ was declared here
> int status, i;
>
>
> So I've just made assignment of 'status = 0' at declaration place -
> but then you have some other unneeded assigns of =0 left around...
> so possibly worth some minor cleanup...
The initialization actually should be -ENODEV. I have changed the
patch and will submit it after the weekend.
Alan Stern
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