NFC: trf7970a: Add driver with ISO/IEC 14443 Type 2 Tag Support

Add a driver for the Texas Instruments TRF7970a RFID/NFC/15693
transceiver.  The driver currently supports ISO/IEC 14443 Type 2
tags only (MIFARE Ultralight and Ultralight C but not Classic).

CC: Erick Macias <emacias@ti.com>
CC: Felipe Balbi <balbi@ti.com>
Signed-off-by: Mark A. Greer <mgreer@animalcreek.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/drivers/nfc/Kconfig b/drivers/nfc/Kconfig
index fe20e1c..65d4ca1 100644
--- a/drivers/nfc/Kconfig
+++ b/drivers/nfc/Kconfig
@@ -26,6 +26,18 @@
 	  Say Y here to compile support for Texas Instrument's NFC WiLink driver
 	  into the kernel or say M to compile it as module.
 
+config NFC_TRF7970A
+	tristate "Texas Instruments TRF7970a NFC driver"
+	depends on SPI && NFC_DIGITAL
+	help
+	  This option enables the NFC driver for Texas Instruments' TRF7970a
+	  device. Such device supports 5 different protocols: ISO14443A,
+	  ISO14443B, FeLiCa, ISO15693 and ISO18000-3.
+
+	  Say Y here to compile support for TRF7970a into the kernel or
+	  say M  to compile it as a module. The module will be called
+	  trf7970a.ko.
+
 config NFC_MEI_PHY
 	tristate "MEI bus NFC device support"
 	depends on INTEL_MEI && NFC_HCI