usb-serial: add support for USB Wishbone-serial adapters

Wishbone is an open hardware SoC bus commonly used in FPGA
designs. Bus access can be serialized using the Etherbone
protocol <http://www.ohwr.org/projects/etherbone-core>.

This driver is intended to be used with devices which attach
their internal Wishbone bus to a USB serial interface using
the Etherbone protocol. A userspace library is required to
speak the protocol made available by this driver as ttyUSBx.

Signed-off-by: Wesley W. Terpstra <w.terpstra@gsi.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/serial/Kconfig

@@ -667,6 +667,23 @@ config USB_SERIAL_ZIO
 	  To compile this driver as a module, choose M here: the
 	  module will be called zio.
 
+config USB_SERIAL_WISHBONE
+	tristate "USB-Wishbone adapter interface driver"
+	help
+	  Say Y here if you want to use a USB attached Wishbone bus.
+
+	  Wishbone is an open hardware SoC bus commonly used in FPGA
+	  designs. Bus access can be serialized using the Etherbone
+	  protocol <http://www.ohwr.org/projects/etherbone-core>.
+
+	  This driver is intended to be used with devices which attach
+	  their internal Wishbone bus to a USB serial interface using
+	  the Etherbone protocol. A userspace library is required to
+	  speak the protocol made available by this driver as ttyUSBx.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called wishbone-serial.
+
 config USB_SERIAL_ZTE
 	tristate "ZTE USB serial driver"
 	help