spi: add driver for J-Core SPI controller

The J-Core "spi2" device is a PIO-based SPI master controller. It
differs from "bitbang" devices in that that it's clocked in hardware
rather than via soft clock modulation over gpio, and performs
byte-at-a-time transfers between the cpu and SPI controller.

This driver will be extended to support future versions of the J-Core
SPI controller with DMA transfers when they become available.

Signed-off-by: Rich Felker <dalias@libc.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index d6fb8d4..1abb3d7 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -285,6 +285,13 @@
 	  This enables using the Freescale i.MX SPI controllers in master
 	  mode.
 
+config SPI_JCORE
+	tristate "J-Core SPI Master"
+	depends on OF && (SUPERH || COMPILE_TEST)
+	help
+	  This enables support for the SPI master controller in the J-Core
+	  synthesizable, open source SoC.
+
 config SPI_LM70_LLP
 	tristate "Parallel port adapter for LM70 eval board (DEVELOPMENT)"
 	depends on PARPORT