usb/158650: uplcom USB To COM Device doesn't transmit data, only receive

[Renato Tambellini]

>Number:         158650
>Category:       usb
>Synopsis:       uplcom USB To COM Device doesn't transmit data, only receive
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-usb
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Tue Jul 05 00:40:09 UTC 2011
>Closed-Date:
>Last-Modified:
>Originator:     Renato Tambellini
>Release:        8.2-STABLE
>Organization:
>Environment:
FreeBSD devilbox.homeunix.net 8.2-STABLE FreeBSD 8.2-STABLE #0: Wed Jun  1 05:48:46 BRT 2011     root at devilbox.homeunix.net:/usr/obj/usr/src/sys/GENERIC  amd64
>Description:
The USB To COM Device Prolific PL-2303 doesn't transmit data, only receive.

# dmesg | grep Prolific
ugen1.4: <Prolific Technology Inc.> at usbus1
uplcom0: <Prolific Technology Inc. USB 2.0 To COM Device, class 0/0,
rev 1.10/3.00, addr 4> on usbus1

# usbconfig -d 1.4 dump_device_desc
ugen1.4: <USB 2.0 To COM Device Prolific Technology Inc.> at usbus1,
cfg=0 md=HOST spd=FULL (12Mbps) pwr=ON

 bLength = 0x0012
 bDescriptorType = 0x0001
 bcdUSB = 0x0110
 bDeviceClass = 0x0000
 bDeviceSubClass = 0x0000
 bDeviceProtocol = 0x0000
 bMaxPacketSize0 = 0x0040
 idVendor = 0x067b
 idProduct = 0x2303
 bcdDevice = 0x0300
 iManufacturer = 0x0001  <Prolific Technology Inc.>
 iProduct = 0x0002  <USB 2.0 To COM Device>
 iSerialNumber = 0x0000  <no string>
 bNumConfigurations = 0x0001
>How-To-Repeat:
1) Plug the DB9 to serial console on another box using a null-modem cable.
2) Plug the device to USB port.
3) Try to access the console:

cu -l /dev/cuaU0 -s 9600

4) The terminal only receive data, not transmit.
>Fix:


>Release-Note:
>Audit-Trail:
>Unformatted: