SPI: MIPS: lantiq: add FALCON spi driver

The external bus unit (EBU) found on the FALCON SoC has spi emulation that is
designed for serial flash access. This driver has only been tested with m25p80
type chips. The hardware has no support for other types of spi peripherals.

Signed-off-by: Thomas Langer <thomas.langer@lantiq.com>
Signed-off-by: John Crispin <blogic@openwrt.org>
Cc: spi-devel-general@lists.sourceforge.net
Cc: linux-mips@linux-mips.org
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Patchwork: https://patchwork.linux-mips.org/patch/3844/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

drivers/spi/Kconfig

@@ -144,6 +144,15 @@ config SPI_EP93XX
 	  This enables using the Cirrus EP93xx SPI controller in master
 	  mode.
 
+config SPI_FALCON
+	tristate "Falcon SPI controller support"
+	depends on SOC_FALCON
+	help
+	  The external bus unit (EBU) found on the FALC-ON SoC has SPI
+	  emulation that is designed for serial flash access. This driver
+	  has only been tested with m25p80 type chips. The hardware has no
+	  support for other types of SPI peripherals.
+
 config SPI_GPIO
 	tristate "GPIO-based bitbanging SPI Master"
 	depends on GENERIC_GPIO