I tried the patch you pointed and it has a similar effect. The cameras work 
with it as well.

________________________________________
From: Sarah Sharp [sarah.a.sh...@linux.intel.com]
Sent: Friday, January 03, 2014 15:06
To: Marius  Silaghi
Cc: linux-usb@vger.kernel.org
Subject: Re: xHCI driver Bug report (Babble reported at enumeration for cam 
that works in Windows)

On Fri, Jan 03, 2014 at 12:48:26AM +0000, Marius  Silaghi wrote:
> Thanks
> Running 3.12.4
>
> During the holiday I managed to solve my problem with the following small 
> patch (could it be added to the mainstream kernel such that it would be 
> solved when we upgrade to the future kernels?):

Hi Marius,

Please try the patch I pointed you to instead of your patch.  Dan's
patch may have the same impact yours does, and I need to know whether
his patch helps, since that's what's currently queued for the upcoming
3.14 kernel.

Sarah Sharp

>
> Signed-off-by: Marius C Silaghi <msila...@fit.edu>
> ---
> --- linux/drivers/usb/core/hub.c.orig   2013-12-23 22:09:50.545093470 -0500
> +++ linux/drivers/usb/core/hub.c        2013-12-23 22:29:40.521043702 -0500
> @@ -4197,7 +4197,19 @@ hub_port_init (struct usb_hub *hub, stru
>                                  break;
>                  }
>
> -               retval = usb_get_device_descriptor(udev, 8);
> +               /*  Try first the old 8-byte query (since it may be expected
> +                *  by some devices), but then give at least a chance to the
> +                *  new form (retrieving the whole descriptor)!
> +                *  Querying the content of the whole structure is required
> +                *  for older USB2 video cameras which do not support partial
> +                *  descriptor queries, like the STC-XXXUSB family.
> +                *  Windows also supports them.
> +                */
> +               if (USE_NEW_SCHEME(retry_counter))
> +                       retval = usb_get_device_descriptor(udev, 8);
> +               else
> +                       retval = usb_get_device_descriptor(udev,
> +                                      sizeof(struct usb_device_descriptor));
>                  if (retval < 8) {
>                          if (retval != -ENODEV)
>                                  dev_err(&udev->dev,--
>
> ________________________________________
> From: Sarah Sharp [sarah.a.sh...@linux.intel.com]
> Sent: Thursday, January 02, 2014 19:24
> To: Marius  Silaghi
> Cc: linux-usb-ow...@vger.kernel.org
> Subject: Re: xHCI driver Bug report (Babble reported at enumeration for cam 
> that works in Windows)
>
> On Sat, Dec 21, 2013 at 04:40:21PM +0000, Marius  Silaghi wrote:
> >
> Hi Marius,
>
> > There is a bug in xHCI. The camera STC-MC33USB that is recognized on the 
> > same computer&port with Windows fails to be enumerated with Babble (-75).
> >
> > I recompiled the kernel with DEBUG on for XHCI and DEBUG_USB.
> >
> > I attach the following files:
> > - dmesg_cam_connect (cat /proc/kmsg output during plugging the USB 
> > connector)
> > - dmesg_cam_disconnect_and_poll (cat /proc/kmsg during a normal xhci ring 
> > poll and then a camera usb unplugging)
> > -lsusb_ehci_Sentech (lsusb -v on a system with ahci where the camera is 
> > recognized)
> > -lsusb_ehci_nothing (lsusb -v on the same system with ahci with nothing 
> > plugged in)
> > -lsusb_xhci_Sentech (lsusb -v on the system with xhci where the camera is 
> > recognized)
> > -lsusb_xhci_nothing (lsusb -v on the same system with xhci with nothing 
> > plugged in)
>
> Thanks for the bug report.  Which kernel version are you running?
>
> I think this issue might be fixed in a patch that's queued for the 3.14
> kernel.  Can you apply the following patch to 3.13-rc6 and see if it
> helps?
>
> http://marc.info/?l=linux-usb&m=138672064109890&w=2
>
> If you need directions on how to compile a custom kernel, please see
> http://kernelnewbies.org/KernelBuild
>
> Sarah Sharp
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to