The HandSpring VISOR is a clone of the PALM-Pilot.
From /usr/src/linux/Documentation/usb/usb-serial.txt:
HandSpring Visor USB docking station Current status: Only when the Visor tries to connect to the host, does the docking station show up as a valid USB device. When this happens, the device is properly enumerated, assigned a port, and then communication _should_ be possible. The driver cleans up properly when the device is removed, or the connection is canceled on the Visor. NOTE: This means that in order to talk to the Visor, the sync button must be pressed BEFORE trying to get any program to communicate to the Visor. This goes against the current documentation for pilot-xfer and other packages, but is the only way that it will work due to the hardware in the Visor. When the device is connected, try talking to it on the second port (this is usually /dev/ttyUSB1 if you do not have any other usb-serial devices in the system.) The system log should tell you which port is the port to use for the HotSync transfer. The "Generic" port can be used for other device communication, such as a PPP link. There is a webpage and mailing lists for this portion of the driver at: http://usbvisor.sourceforge.net/
Handspring VISOR Platinum serial port is tunneld through USB, so load usbserial.o with modul parameters vendor=0x82d product=0x100 (usbmgr.conf) USB is made activ by starting the HotSync synchronisation per: pilot-xfer /dev/ttyUSB0 -b -/visor/