kern/39068: first character (sometimes) not transmitted by the usbmodem driver

[leo%marco.de@localhost]

>Number:         39068
>Category:       kern
>Synopsis:       first character (sometimes) not transmitted by the usbmodem 
>driver
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Mon Jun 30 09:15:00 +0000 2008
>Originator:     Matthias Pfaller
>Release:        NetBSD 4.99.67
>Organization:
Matthias Pfaller                            Software Entwicklung
marco Systemanalyse und Entwicklung GmbH    Tel   +49 8131 5161-41
Hans-Böckler-Str. 2, D 85221 Dachau         Fax   +49 8131 5161-66
http://www.marco.de/                        Email leo%dachau.marco.de@localhost
>Environment:
System: NetBSD joghurt 4.99.67 NetBSD 4.99.67 (JOGHURT) #9: Mon Jun 30 10:42:35 
CEST 2008 leo@joghurt:/usr/src/sys/arch/i386/compile/JOGHURT i386
Architecture: i386
Machine: i386
>Description:
When connecting to a usb modem/com device (cu -l /dev/ttyU0), the first
character is sometimes not transmitted to the device. I checked using a
"nokia navigator 6110", a ftdi com adapter and a device developed by us.
>How-To-Repeat:
Connect to the serial device (e.g. using cu) and send a single
character (in case of cu this has to be a 0x0d). This character is
transmitted. Disconnect from the device (in case of cu ~.) and reconnect.
The next character you type is not transmitted. The second character
will get transmitted. As long as you transmit at least two characters
before disconnecting, the first character of the next connection
will get transmitted. If you only send a single character, the
first character of the next connection will get dropped.

>Fix:

Unknown