USB CDC NCM host driver

The patch provides USB CDC NCM host driver support in the Linux Kernel.

Changes:
drivers/net/usb/cdc_ncm.c:
- initial submission of the CDC NCM host driver;
- verified on Intel 32/64 bit, Intel Atom, ST-Ericsson U8500 (ARM)
- throughput measured over 100 Mbits duplex;
- driver supports 16-bit NTB format only, but it is more than enough for
  transfers up to 64K;
- driver can handle up to 32 datagrams in received NTB;
- timer is used to collect several packets in Tx direction

drivers/net/usb/Kconfig:
- a new entry to compile CDC NCM host driver
drivers/net/usb/Makefile:
- a new entry to compile CDC NCM host driver
Signed-off-by: Alexey Orishko <alexey.orishko@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/usb/Kconfig

@@ -196,6 +196,25 @@ config USB_NET_CDC_EEM
 	  IEEE 802 "local assignment" bit is set in the address, a "usbX"
 	  name is used instead.
 
+config USB_NET_CDC_NCM
+	tristate "CDC NCM support"
+	depends on USB_USBNET
+	default y
+	help
+	  This driver provides support for CDC NCM (Network Control Model
+	  Device USB Class Specification). The CDC NCM specification is
+	  available from <http://www.usb.org/>.
+
+	  Say "y" to link the driver statically, or "m" to build a
+	  dynamically linked module.
+
+	  This driver should work with at least the following devices:
+	    * ST-Ericsson M700 LTE FDD/TDD Mobile Broadband Modem (ref. design)
+	    * ST-Ericsson M5730 HSPA+ Mobile Broadband Modem (reference design)
+	    * ST-Ericsson M570 HSPA+ Mobile Broadband Modem (reference design)
+	    * ST-Ericsson M343 HSPA Mobile Broadband Modem (reference design)
+	    * Ericsson F5521gw Mobile Broadband Module
+
 config USB_NET_DM9601
 	tristate "Davicom DM9601 based USB 1.1 10/100 ethernet devices"
 	depends on USB_USBNET

drivers/net/usb/Makefile

@@ -26,4 +26,5 @@ obj-$(CONFIG_USB_CDC_PHONET)	+= cdc-phonet.o
 obj-$(CONFIG_USB_IPHETH)	+= ipheth.o
 obj-$(CONFIG_USB_SIERRA_NET)	+= sierra_net.o
 obj-$(CONFIG_USB_NET_CX82310_ETH)	+= cx82310_eth.o
+obj-$(CONFIG_USB_NET_CDC_NCM)	+= cdc_ncm.o