USB-serial console problem using uftdi, ucom an cu

[Petri Laakso <petri.laakso%asd.fi@localhost>]

Hi

I'm connected to my developement board using cu and USB-cable which has 
FTDI 2332H chip, like this:

# cu -f -l /dev/ttyU1 -s 115200

When I'm generating just a little bit of output at the time, like issuing
commands like "pwd", "whoami" etc. everything works fine.
When I'm generating more output, lets say more than ~35 charactes, like
"ls", "uname -a" USB-serial connection just stalls.

I hacked uftdi.c to detect my gadget, by adding USB product ID and driver
seems to be working right. from dmesg:

uhub6: 2 ports with 2 removable, self powered
uftdi0 at uhub6 port 1
uftdi_attach: sc=0xcbb53cf0
uftdi0: FTDI BeagleBone, rev 2.00/7.00, addr 6
uftdi: in=0x81 out=0x2
ucom0 at uftdi0 portno 1
uftdi: in=0x83 out=0x4
ucom1 at uftdi0 portno 2

I'm using 5.1_STABLE.

Could this be some sort of buffering problem? Maybe some buffer overflows
because I am not able to read it quick enough. Any ideas welcome.

This command will output for ever:

root@beaglebone:~# for n in `seq 1 100`; do echo -n $n; sleep 1; done
                                                        ^^^^^^^
This command will stall output very quickly:

root@beaglebone:~# for n in `seq 1 100`; do echo -n $n; done

Petri