NFC: SHDLC implementation

Most NFC HCI chipsets actually use a simplified HDLC link layer to
carry HCI payloads.
This implementation registers itself as an HCI device on behalf of the
NFC driver.

Signed-off-by: Eric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/nfc/hci/Kconfig b/net/nfc/hci/Kconfig
index c32d2d4..17213a6 100644
--- a/net/nfc/hci/Kconfig
+++ b/net/nfc/hci/Kconfig
@@ -6,3 +6,11 @@
 	 Say Y here if you want to build support for a kernel NFC HCI
 	 implementation. This is mostly needed for devices that only process
 	 HCI frames, like for example the NXP pn544.
+
+config NFC_SHDLC
+	depends on NFC_HCI
+	bool "SHDLC link layer for HCI based NFC drivers"
+	default n
+	---help---
+	  Say yes if you use an NFC HCI driver that requires SHDLC link layer.
+	  If unsure, say N here.