Hi, I am running Fedora Core 1 and have problem when I try to connect the USB-Serial adapter (from KeySpan) Then I patch the file (provided from KeySpan) and recompiled the kernel. It works. I was able to receive data. Then someone has tried to use different USB-Serial adapter (from Cables Unlimited) It didn't work for him on my machine. Now, I try to plug back my KeySpan. I couldn't receive data anymore. I opened the /dev/ttyUSB0 file and it gave me back a fd. But I then when I tried to send data from other computer. I wouldn't read it. I am wondering if the driver for this device has been corrupted. BTW, when I do dmesg it looks like it recognize the device though.

Here some of the message that I got when I did dmesg:
lp0: using parport0 (polling).
lp0: console ready
hdc: attached ide-cdrom driver.
hdc: ATAPI 48X CD-ROM drive, 128kB Cache, DMA
Uniform CD-ROM driver Revision: 3.12
cdrom: This disc doesn't have any tracks I recognize!
usb-uhci.c: interrupt, status 3, frame# 539
usb.c: USB disconnect on device 00:1d.2-1 address 2
usbserial.c: Keyspan 1 port adapter converter now disconnected from ttyUSB0
hub.c: new USB device 00:1d.2-1, assigned address 3
usb.c: USB device 3 (vend/prod 0x403/0x6001) is not claimed by any active driver.
usbserial.c: USB Serial support registered for FTDI SIO
usbserial.c: USB Serial support registered for FTDI 8U232AM Compatible
usbserial.c: USB Serial support registered for FTDI FT232BM Compatible
usbserial.c: FTDI FT232BM Compatible converter detected
usbserial.c: FTDI FT232BM Compatible converter now attached to ttyUSB0 (or usb/tts/0 for devfs)
usbserial.c: USB Serial support registered for USB-UIRT Infrared Receiver/Transmitter
usbserial.c: USB Serial support registered for Home-Electronics TIRA-1 IR Transceiver
ftdi_sio.c: v1.3.4:USB FTDI Serial Converters Driver
usb.c: USB disconnect on device 00:1d.2-1 address 3
usbserial.c: FTDI FT232BM Compatible converter now disconnected from ttyUSB0
hub.c: new USB device 00:1d.2-1, assigned address 4
usbserial.c: FTDI FT232BM Compatible converter detected
usbserial.c: FTDI FT232BM Compatible converter now attached to ttyUSB0 (or usb/tts/0 for devfs)
usb.c: USB disconnect on device 00:1d.2-1 address 4
usbserial.c: FTDI FT232BM Compatible converter now disconnected from ttyUSB0
hub.c: new USB device 00:1d.2-1, assigned address 5
usbserial.c: Keyspan 1 port adapter converter detected
usbserial.c: Keyspan 1 port adapter converter now attached to ttyUSB0 (or usb/tts/0 for devfs)
usb-uhci.c: interrupt, status 3, frame# 1291
usb.c: USB disconnect on device 00:1d.2-1 address 5
usbserial.c: Keyspan 1 port adapter converter now disconnected from ttyUSB0

Appreciate your help!
OC

Did you ever figure out this problem with the keyspan? I'm having a very similar problem on both a 2.4.22 and a 2.6.8 kernel. Mine disconnects after the usb printer(s) connect. Thanks!!