# Thinkpad X61s: Serial port I/O error after undocking/docking

## chrisjt

Hi,

I'm using Gentoo x86_64 with Kernel 2.6.33-r1 on an Thinkpad X61s together with the X61 Ultrabase (Docking Station). The docking station is equipped with an old-style serial port which I use for a special Infrared transmitter.

Everything works well until I undock the machine and put it back into the docking station. dmesg reports after docking that the serial ports were found (Serial: 8250/16550 driver, 4 ports, IRQ sharing disabled), but access to ttyS0 gives me an /dev/ttyS0: Input/output error. I tried unloading the modules 8250, 8250_pnp and serial_core, but this doesn't help.

Other devices like the DVD drive inside the dock and the USB ports work well after un/docking.

Is there any chance to get this working or do I have to reboot every time?

Best regards,

chris

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## cwr

I used to have to unload and reload a number of serial port (and sound) modules on

my very old Thinkpad to keep stuff working across suspends.  I think if you keep

looking you'll be able to find the modules that need re-setting.

Good luck - Will

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