mtd: nand: add sunxi NAND flash controller support

Add support for the sunxi NAND Flash Controller (NFC).
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
[Brian: tweaked to fix ecc->steps issue]
Signed-off-by: Brian Norris <computersforpeace@gmail.com>

drivers/mtd/nand/Kconfig

@@ -516,4 +516,10 @@ config MTD_NAND_XWAY
 	  Enables support for NAND Flash chips on Lantiq XWAY SoCs. NAND is attached
 	  to the External Bus Unit (EBU).
 
+config MTD_NAND_SUNXI
+	tristate "Support for NAND on Allwinner SoCs"
+	depends on ARCH_SUNXI
+	help
+	  Enables support for NAND Flash chips on Allwinner SoCs.
+
 endif # MTD_NAND

drivers/mtd/nand/Makefile

@@ -50,5 +50,6 @@ obj-$(CONFIG_MTD_NAND_JZ4740)		+= jz4740_nand.o
 obj-$(CONFIG_MTD_NAND_GPMI_NAND)	+= gpmi-nand/
 obj-$(CONFIG_MTD_NAND_XWAY)		+= xway_nand.o
 obj-$(CONFIG_MTD_NAND_BCM47XXNFLASH)	+= bcm47xxnflash/
+obj-$(CONFIG_MTD_NAND_SUNXI)		+= sunxi_nand.o
 
 nand-objs := nand_base.o nand_bbt.o nand_timings.o