On Tue, Dec 18, 2012 at 01:13:05AM -0500, Marius Silaghi wrote: Hi Marius, thanks for reporting this. > My USB2.0 cameras are enumerated fine on ehci systems. But not on my new Ubuntu > 12.10: > $uname -a > Linux VAIO 3.5.0-18-generic #29-Ubuntu SMP Fri Oct 19 10:26:51 UTC 2012 x86_64 > x86_64 x86_64 GNU/Linux > > here xhci_hcd is compiled in the kernel, and the device is not enumerated. I > tried unbinding xhci using the sysfs and the messages dissapear, but ehci does > not take over. Any idea? Most xHCI host controllers don't share ports with the EHCI controller, so unbinding the xHCI driver doesn't switch the ports over. Even on the Intel xHCI hosts that can switch ports between the xHCI host and the EHCI host, we don't switch the ports back on xHCI driver unload. > [12241.536789] usb 3-1: new high-speed USB device number 8 using xhci_hcd > [12241.553375] usb 3-1: device descriptor read/8, error -75 > [12241.673302] usb 3-1: device descriptor read/8, error -75 > [12241.888420] usb 3-1: new high-speed USB device number 9 using xhci_hcd > [12241.905029] usb 3-1: device descriptor read/8, error -75 > [12242.024764] usb 3-1: device descriptor read/8, error -75 > [12242.240032] usb 3-1: new high-speed USB device number 10 using xhci_hcd > [12242.256595] usb 3-1: device descriptor read/8, error -75 > [12242.376524] usb 3-1: device descriptor read/8, error -75 > [12242.591580] usb 3-1: new high-speed USB device number 11 using xhci_hcd > [12242.608170] usb 3-1: device descriptor read/8, error -75 > [12242.727987] usb 3-1: device descriptor read/8, error -75 > [12242.831348] hub 3-0:1.0: unable to enumerate USB device on port 1 Can you recompile your kernel with CONFIG_USB_DEBUG and CONFIG_USB_XHCI_HCD_DEBUGGING turned on? If you need instructions, please follow the directions for compiling the latest stable kernel here: http://kernelnewbies.org/KernelBuild Then send me the dmesg output from just before you plugged in the device. Please also send me the output of `sudo lsusb -v` with the device plugged into a system with an EHCI controller. However, I will say that at a quick glance, it looks like your hardware may have electrical issues under the xHCI host controller. The -75 error code is for EOVERFLOW, which means your device "babbled" on a transfer. There's not much software can do about electrical issues, if that is the true root cause. Sarah Sharp -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
