staging: mt7621-spi: add mt7621 support

NeilBrown:
    The code will fail with a warning if asked to transfer
    more than 32 bytes at a time.  So used max_transfer_size
    interface to tell users about this.
Signed-off-by: John Crispin <blogic@openwrt.org>
Signed-off-by: NeilBrown <neil@brown.name>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/Kconfig

@@ -122,4 +122,6 @@ source "drivers/staging/mt7621-pinctrl/Kconfig"
 
 source "drivers/staging/mt7621-gpio/Kconfig"
 
+source "drivers/staging/mt7621-spi/Kconfig"
+
 endif # STAGING

drivers/staging/Makefile

@@ -52,3 +52,4 @@ obj-$(CONFIG_PI433)		+= pi433/
 obj-$(CONFIG_SOC_MT7621)	+= mt7621-pci/
 obj-$(CONFIG_SOC_MT7621)	+= mt7621-pinctrl/
 obj-$(CONFIG_SOC_MT7621)	+= mt7621-gpio/
+obj-$(CONFIG_SOC_MT7621)	+= mt7621-spi/

drivers/staging/mt7621-spi/Kconfig

+config SPI_MT7621
+	tristate "MediaTek MT7621 SPI Controller"
+	depends on RALINK
+	help
+	  This selects a driver for the MediaTek MT7621 SPI Controller.
+

drivers/staging/mt7621-spi/Makefile

+obj-$(CONFIG_SPI_MT7621)		+= spi-mt7621.o

drivers/staging/mt7621-spi/TODO

+
+- general code review and clean up
+- ensure device-tree requirements are documented
+
+Cc: NeilBrown <neil@brown.name>