usb gadget: cdc obex glue

The following patch introduces a new f_obex.c function driver.
It allows userspace obex servers to use usb as transport layer
for their messages.

[ dbrownell@users.sourceforge.net: various fixes and cleanups ]

Signed-off-by: Felipe Balbi <felipe.balbi@nokia.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Documentation/DocBook/gadget.tmpl

@@ -557,6 +557,9 @@ Near-term plans include converting all of them, except for "gadgetfs".
 </para>
 
 !Edrivers/usb/gadget/f_acm.c
+!Edrivers/usb/gadget/f_ecm.c
+!Edrivers/usb/gadget/f_subset.c
+!Edrivers/usb/gadget/f_obex.c
 !Edrivers/usb/gadget/f_serial.c
 
 </sect1>

drivers/usb/gadget/Kconfig

@@ -576,19 +576,23 @@ config USB_FILE_STORAGE_TEST
 	  normal operation.
 
 config USB_G_SERIAL
-	tristate "Serial Gadget (with CDC ACM support)"
+	tristate "Serial Gadget (with CDC ACM and CDC OBEX support)"
 	help
 	  The Serial Gadget talks to the Linux-USB generic serial driver.
 	  This driver supports a CDC-ACM module option, which can be used
 	  to interoperate with MS-Windows hosts or with the Linux-USB
 	  "cdc-acm" driver.
 
+	  This driver also supports a CDC-OBEX option.  You will need a
+	  user space OBEX server talking to /dev/ttyGS*, since the kernel
+	  itself doesn't implement the OBEX protocol.
+
 	  Say "y" to link the driver statically, or "m" to build a
 	  dynamically linked module called "g_serial".
 
 	  For more information, see Documentation/usb/gadget_serial.txt
 	  which includes instructions and a "driver info file" needed to
-	  make MS-Windows work with this driver.
+	  make MS-Windows work with CDC ACM.
 
 config USB_MIDI_GADGET
 	tristate "MIDI Gadget (EXPERIMENTAL)"