This patch adds support for the FTDI FT2232C USB to dual serial port
converter to the ftdi_sio driver.

The patch is based on a fork of the 2.4 ftdi_sio driver by Steven
Turner of FTDI, and a preliminary port of these changes to the 2.6
ftdi_sio driver by Rus V. Brushkoff.  I've tidied it up and fixed a
couple of things.

I don't have a FT2232C to test it with, but Steven Turner of FTDI
has tested it.  He mentioned a couple of known problems with the
driver, but nothing to do with this patch.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>