My Philips SPC 1300NC webcam is not recognised when I plug it in. The kernel reports "unable to enumerate USB device on port X" in an infinite loop. To get the webcam running I have to reload the ehci_hcd module. My Logitech webcam works fine on the same machine. i.e. the USB port is not broken. System: IBM Thinkpad T42 OS: Debian Squeeze, Kernel: 2.6.36-rc5-686 Original Bug report: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=598784 lsusb: Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub dmesg: [ 378.284388] hub 1-0:1.0: unable to enumerate USB device on port 4 [ 378.540147] usb 1-4: new high speed USB device using ehci_hcd and address 70 [ 378.608494] hub 1-0:1.0: unable to enumerate USB device on port 4 [ 378.809418] hub 1-0:1.0: unable to enumerate USB device on port 4 [ 378.996430] hub 1-0:1.0: unable to enumerate USB device on port 4 [ 379.184319] hub 1-0:1.0: unable to enumerate USB device on port 4 [ 379.372334] hub 1-0:1.0: unable to enumerate USB device on port 4 [ 379.560345] hub 1-0:1.0: unable to enumerate USB device on port 4 [ 379.748487] hub 1-0:1.0: unable to enumerate USB device on port 4 [ 379.936528] hub 1-0:1.0: unable to enumerate USB device on port 4 [ 380.124390] hub 1-0:1.0: unable to enumerate USB device on port 4 [ 380.368148] usb 1-4: new high speed USB device using ehci_hcd and address 79 [ 380.436367] hub 1-0:1.0: unable to enumerate USB device on port 4 ... To get it running I have to reload the ehci_hcd module each time I use it: sudo modprobe -r ehci_hcd And it works (in Cheese). lsusb: Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 003 Device 002: ID 0471:0331 Philips (or NXP) SPC 1300NC PC Camera Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub dmesg: [ 463.728507] hub 1-0:1.0: unable to enumerate USB device on port 4 [ 463.876590] ehci_hcd 0000:00:1d.7: remove, state 1 [ 463.876600] usb usb1: USB disconnect, address 1 [ 463.928064] hub 1-0:1.0: hub_port_status failed (err = -19) [ 463.928081] hub 1-0:1.0: cannot disable port 4 (err = -19) [ 463.928105] hub 1-0:1.0: cannot reset port 4 (err = -19) [ 463.928116] hub 1-0:1.0: cannot disable port 4 (err = -19) [ 463.928130] hub 1-0:1.0: cannot reset port 4 (err = -19) [ 463.928140] hub 1-0:1.0: cannot disable port 4 (err = -19) [ 463.928155] hub 1-0:1.0: cannot reset port 4 (err = -19) [ 463.928165] hub 1-0:1.0: cannot disable port 4 (err = -19) [ 463.928176] hub 1-0:1.0: unable to enumerate USB device on port 4 [ 463.928185] hub 1-0:1.0: cannot disable port 4 (err = -19) [ 463.986359] ehci_hcd 0000:00:1d.7: USB bus 1 deregistered [ 463.986403] ehci_hcd 0000:00:1d.7: PCI INT D disabled [ 464.236062] usb 3-2: new full speed USB device using uhci_hcd and address 2 [ 464.433234] usb 3-2: config 1 has an invalid descriptor of length 7, skipping remainder of the config [ 464.455227] usb 3-2: New USB device found, idVendor=0471, idProduct=0331 [ 464.455238] usb 3-2: New USB device strings: Mfr=2, Product=1, SerialNumber=0 [ 464.455248] usb 3-2: Product: Philips SPC 1300NC Webcam [ 464.455256] usb 3-2: Manufacturer: Philips CE [ 464.455487] usb 3-2: configuration #1 chosen from 1 choice [ 464.716237] 2:3:1 : no or invalid class specific endpoint descriptor [ 464.728897] usbcore: registered new interface driver snd-usb-audio [ 464.793189] Linux video capture interface: v2.00 [ 465.038049] uvcvideo: Found UVC 1.00 device Philips SPC 1300NC Webcam (0471:0331) [ 465.046775] input: Philips SPC 1300NC Webcam as /devices/pci0000:00/0000:00:1d.1/usb3/3-2/3-2:1.0/input/input11 [ 465.047115] usbcore: registered new interface driver uvcvideo [ 465.047900] USB Video Class driver (v0.1.0)