USB SL811 and serial devices FTDI SIO or PL2303

I'm using x86 kernel 2.4.20 and a embedded USB host controller SL811 from
Cypress.

I have two serial adapters, used with drivers FTDI SIO and Prolific PL2303.
These drivers have the following problems:
I can only transmit data
CR and LF can not send as raw
I can not receive any data or control signals (CTS, DCD)
After insert, I see some "usb_control/bulk_msg: timeout"
If I remove hardware, drivers crashed with NULL pointer

The loades drivers for USB:
pl2303                  9784   0
usbserial              17544   0 [pl2303]
hc_sl811               12636   0 (unused)
usbcore                55040   1 [pl2303 usbserial hc_sl811]

The same serial driver driver on my desktop have the same probem.

Hardware is OK. System works fine with USB-Floppy and memory sticks. I can
insert and remove, mount and umount and all other things.

Anybody works with this USB ore serial devices on USB controller?
Who has some suggestions?

Henry Nestler
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SSV SOFTWARE SYSTEMS GmbH
Heisterbergallee 72
D-30453 Hannover
http://www.ssv-embedded.de
Phone: +49(0)511/40 000-0
Fax:   +49(0)511/40 000-40
Email: snipped-for-privacy@ist1.de
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