is there an issue with USB-serial converter support?

[Robert P. J. Day]

  here's what's happening.  f11 x86_64 updated beta, connected to an
embedded (beagleboard) system thusly:

  host USB port <->
    regular USB cable <->
      targus port replicator with serial port <->
        null modem cable <->
          everex PC AT cable (DB9 to 10-pin connector)

works fine -- minicom at 115200 8N1, no flow control, and device file
/dev/ttyUSB0.  when i plug it in, my host /var/log/messages appears
thusly:

ay  8 19:47:19 localhost kernel: usb 2-1.4: new full speed USB device
using ohci_hcd and address 74
May  8 19:47:19 localhost kernel: usb 2-1.4: New USB device found,
idVendor=0711, idProduct=0230
May  8 19:47:19 localhost kernel: usb 2-1.4: New USB device strings:
Mfr=1, Product=2, SerialNumber=3
May  8 19:47:19 localhost kernel: usb 2-1.4: Manufacturer: USB-RS232
Interface Converter
May  8 19:47:19 localhost kernel: usb 2-1.4: SerialNumber: 204395
May  8 19:47:19 localhost kernel: usb 2-1.4: configuration #1 chosen
from 1 choice
May  8 19:47:19 localhost kernel: mct_u232 2-1.4:1.0: MCT U232
converter detected
May  8 19:47:19 localhost kernel: usb 2-1.4: MCT U232 converter now
attached to ttyUSB0
May  8 19:47:19 localhost NetworkManager: <info>  (ttyUSB0): ignoring
due to lack of mobile broadband capabilties

looks good, and i'm connected to the console on the beagle board.

  what i want to do now is replace the clunky targus port replicator
with a USB-serial converter to give me:

  host USB port <->
    no-name USB-serial converter cable <->
      null modem cable <->
        everex PC AT cable (DB9 to 10-pin connector)

but i've yet to get that to work properly.  when i plug in the
converter, i get:

May  8 19:57:21 localhost kernel: usb 2-1: new full speed USB device
using ohci_hcd and address 78
May  8 19:57:22 localhost kernel: usb 2-1: New USB device found,
idVendor=067b, idProduct=2303
May  8 19:57:22 localhost kernel: usb 2-1: New USB device strings:
Mfr=1, Product=2, SerialNumber=0
May  8 19:57:22 localhost kernel: usb 2-1: Product: USB-Serial
Controller
May  8 19:57:22 localhost kernel: usb 2-1: Manufacturer: Prolific
Technology Inc.
May  8 19:57:22 localhost kernel: usb 2-1: configuration #1 chosen
from 1 choice
May  8 19:57:22 localhost kernel: pl2303 2-1:1.0: pl2303 converter
detected
May  8 19:57:22 localhost kernel: usb 2-1: pl2303 converter now
attached to ttyUSB0
May  8 19:57:22 localhost NetworkManager: <info>  (ttyUSB0): ignoring
due to lack of mobile broadband capabilties

  except that what i see in minicom is crap -- lots of unprintable
characters, as if it's running at the wrong baud rate or something.  i
didn't do anything special when i plugged in the converter, and here's
the first few lines from "modinfo pl2303":

filename:
/lib/modules/2.6.29.2-129.fc11.x86_64/kernel/drivers/usb/serial/pl2303.ko
license:        GPL
description:    Prolific PL2303 USB to serial adaptor driver
srcversion:     EF203DC966F54AFA826B33F
...

  is there a known issue with USB-serial converters?  i just noticed
that that module has a single load-time parameter:

debug:Debug enabled or not (bool)

so i guess i can try that next and see what happens.  but i was
expecting this to work right out of the box, as they say.

rday
--

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Robert P. J. Day                               Waterloo, Ontario, CANADA

        Linux Consulting, Training and Annoying Kernel Pedantry.

Web page:                                          http://crashcourse.ca
Linked In:                             http://www.linkedin.com/in/rpjday
Twitter:                                       http://twitter.com/rpjday
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