fs/littlefs: VFS wrapper improvement: (1) Support block device interface, (2) support ioctl, stat and sync file operation, (3) support forceformat and autoformat option, (4) update file->f_pos and dir->fd_position, (5)remote the internal struct from dir, and (6) emove mtd byte read/write requirement.

fs/littlefs/Kconfig

@@ -3,7 +3,7 @@ config FS_LITTLEFS
 	default n
 	select FS_READABLE
 	select FS_WRITABLE
-	depends on !DISABLE_MOUNTPOINT && MTD_BYTE_WRITE && EXPERIMENTAL
+	depends on !DISABLE_MOUNTPOINT
 	---help---
 		Build the LITTLEFS file system. https://github.com/ARMmbed/littlefs.
 

fs/littlefs/README.md

@@ -1,6 +1,6 @@
 ## usage 
 
-depends on !DISABLE_MOUNTPOINT && MTD_BYTE_WRITE
+depends on !DISABLE_MOUNTPOINT
 
 1. register_mtddriver("/dev/w25", mtd, 0755, NULL);  
 2. mount("/dev/w25", "/w25", "littlefs", 0, NULL);

fs/mount/fs_mount.c

@@ -72,7 +72,7 @@
  */
 
 #if defined(CONFIG_FS_FAT) || defined(CONFIG_FS_ROMFS) || \
-    defined(CONFIG_FS_SMARTFS)
+    defined(CONFIG_FS_SMARTFS) || defined(CONFIG_FS_LITTLEFS)
 #  define BDFS_SUPPORT 1
 #endif
 
@@ -117,6 +117,9 @@ extern const struct mountpt_operations romfs_operations;
 #ifdef CONFIG_FS_SMARTFS
 extern const struct mountpt_operations smartfs_operations;
 #endif
+#ifdef CONFIG_FS_LITTLEFS
+extern const struct mountpt_operations littlefs_operations;
+#endif
 
 static const struct fsmap_t g_bdfsmap[] =
 {
@@ -128,6 +131,9 @@ static const struct fsmap_t g_bdfsmap[] =
 #endif
 #ifdef CONFIG_FS_SMARTFS
     { "smartfs", &smartfs_operations },
+#endif
+#ifdef CONFIG_FS_LITTLEFS
+    { "littlefs", &littlefs_operations },
 #endif
     { NULL,   NULL },
 };