drivers/mtd/gd5f.c: Add gigadevice SPI NAND FLASH driver.

drivers/mtd/Kconfig

@@ -1026,3 +1026,20 @@ config GD25_SLOWREAD
 	default n
 
 endif # MTD_GD25
+
+config MTD_GD5F
+	bool "SPI-based GD5F nand FLASH"
+	default n
+	select SPI
+
+if MTD_GD5F
+
+config GD5F_SPIMODE
+	int "GD5F SPI Mode"
+	default 0
+
+config GD5F_SPIFREQUENCY
+	int "GD5F SPI Frequency"
+	default 20000000
+
+endif # MTD_GD5F

drivers/mtd/Make.defs

@@ -112,6 +112,10 @@ ifeq ($(CONFIG_MTD_GD25),y)
 CSRCS += gd25.c
 endif
 
+ifeq ($(CONFIG_MTD_GD5F),y)
+CSRCS += gd5f.c
+endif
+
 ifeq ($(CONFIG_MTD_AT25),y)
 CSRCS += at25.c
 endif

include/nuttx/mtd/mtd.h

@@ -534,6 +534,16 @@ FAR struct mtd_dev_s *w25_initialize(FAR struct spi_dev_s *dev);
 
 FAR struct mtd_dev_s *gd25_initialize(FAR struct spi_dev_s *dev);
 
+/****************************************************************************
+ * Name: gd5f_initialize
+ *
+ * Description:
+ *   Initializes the driver for SPI-based GD5F FLASH
+ *
+ ****************************************************************************/
+
+FAR struct mtd_dev_s *gd5f_initialize(FAR struct spi_dev_s *dev);
+
 /****************************************************************************
  * Name: s25fl1_initialize
  *