Input: add Pegasus Notetaker tablet driver

This adds a driver for the Pegasus Notetaker Pen. When connected,
this uses the Pen as an input tablet.

This device was sold in various different brandings, for example
 "Pegasus Mobile Notetaker M210",
 "Genie e-note The Notetaker",
 "Staedtler Digital ballpoint pen 990 01",
 "IRISnotes Express" or
 "NEWLink Digital Note Taker".

Here's an example, so that you know what we are talking about:
http://www.genie-online.de/genie-e-note-2/

https://pegatech.blogspot.com/ seems to be a remaining official resource.

This device can also transfer saved (offline recorded handwritten) data and
there are userspace programs that do this, see https://launchpad.net/m210
(Well, alternatively there are really fast scanners out there :)

It's *really* fun to use as an input tablet though! So let's support this
for everybody.
Signed-off-by: Martin Kepplinger <martink@posteo.de>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/tablet/Kconfig

@@ -73,6 +73,21 @@ config TABLET_USB_KBTAB
 	  To compile this driver as a module, choose M here: the
 	  module will be called kbtab.
 
+config TABLET_USB_PEGASUS
+	tristate "Pegasus Mobile Notetaker Pen input tablet support"
+	depends on USB_ARCH_HAS_HCD
+	select USB
+	help
+	  Say Y here if you want to use the Pegasus Mobile Notetaker,
+	  also known as:
+	  Genie e-note The Notetaker,
+	  Staedtler Digital ballpoint pen 990 01,
+	  IRISnotes Express or
+	  NEWLink Digital Note Taker.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called pegasus_notetaker.
+
 config TABLET_SERIAL_WACOM4
 	tristate "Wacom protocol 4 serial tablet support"
 	select SERIO

drivers/input/tablet/Makefile

@@ -8,4 +8,5 @@ obj-$(CONFIG_TABLET_USB_AIPTEK)	+= aiptek.o
 obj-$(CONFIG_TABLET_USB_GTCO)	+= gtco.o
 obj-$(CONFIG_TABLET_USB_HANWANG) += hanwang.o
 obj-$(CONFIG_TABLET_USB_KBTAB)	+= kbtab.o
+obj-$(CONFIG_TABLET_USB_PEGASUS) += pegasus_notetaker.o
 obj-$(CONFIG_TABLET_SERIAL_WACOM4) += wacom_serial4.o