CP2102 UART adapter not attaching

[Mark Johnston]

Hi,

I have the module listed here:
http://www.amazon.com/KEDSUM%C2%AE-CP2102-Module-Download-Converter/dp/B009T2ZR6W

Under Windows 8 it works perfectly, but on FreeBSD-CURRENT I get:

usb_alloc_device: set address 3 failed (USB_ERR_STALLED, ignored)
usbd_setup_device_desc: getting device descriptor at addr 3 failed, USB_ERR_STALLED
usbd_req_re_enumerate: addr=3, set address failed! (USB_ERR_STALLED, ignored)
usbd_setup_device_desc: getting device descriptor at addr 3 failed, USB_ERR_STALLED
usbd_req_re_enumerate: addr=3, set address failed! (USB_ERR_STALLED, ignored)
usbd_setup_device_desc: getting device descriptor at addr 3 failed, USB_ERR_STALLED
usbd_req_re_enumerate: addr=3, set address failed! (USB_ERR_STALLED, ignored)
usbd_setup_device_desc: getting device descriptor at addr 3 failed, USB_ERR_STALLED
usbd_req_re_enumerate: addr=3, set address failed! (USB_ERR_STALLED, ignored)
usbd_setup_device_desc: getting device descriptor at addr 3 failed, USB_ERR_STALLED
ugen1.3: <Unknown> at usbus1 (disconnected)
uhub_reattach_port: could not allocate new device

It looks like this device should be handled by uslcom(4), but it looks
like we can't even get the device descriptor. How can I go about
debugging this?

Thanks,
-Mark