spi/spi_bfin_sport: new driver for a SPI bus via the Blackfin SPORT peripheral

The Blackfin SPORT peripheral is a pretty flexible device.  With enough
coaching, we can make it generate SPI compatible waveforms.  This is
desirable as the SPORT can run at much higher clock frequencies than the
dedicated on-chip SPI peripheral, and it can do full duplex DMA.  It also
opens up the possibility of multiple SPI buses in case someone wants to
dedicate a whole bus to a specific part that does not play well with
others.

Signed-off-by: Cliff Cai <cliff.cai@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

drivers/spi/Kconfig

@@ -80,6 +80,15 @@ config SPI_BFIN
 	help
 	  This is the SPI controller master driver for Blackfin 5xx processor.
 
+config SPI_BFIN_SPORT
+	tristate "SPI bus via Blackfin SPORT"
+	depends on BLACKFIN
+	help
+	  Enable support for a SPI bus via the Blackfin SPORT peripheral.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called spi_bfin_sport.
+
 config SPI_AU1550
 	tristate "Au1550/Au12x0 SPI Controller"
 	depends on (SOC_AU1550 || SOC_AU1200) && EXPERIMENTAL

drivers/spi/Makefile

@@ -13,6 +13,7 @@ obj-$(CONFIG_SPI_ALTERA)		+= spi_altera.o
 obj-$(CONFIG_SPI_ATMEL)			+= atmel_spi.o
 obj-$(CONFIG_SPI_ATH79)			+= ath79_spi.o
 obj-$(CONFIG_SPI_BFIN)			+= spi_bfin5xx.o
+obj-$(CONFIG_SPI_BFIN_SPORT)		+= spi_bfin_sport.o
 obj-$(CONFIG_SPI_BITBANG)		+= spi_bitbang.o
 obj-$(CONFIG_SPI_AU1550)		+= au1550_spi.o
 obj-$(CONFIG_SPI_BUTTERFLY)		+= spi_butterfly.o