gpio: use appropriate return values for cmd handler

[karo-tx-uboot.git] / doc / README.ext4

diff --git a/doc/README.ext4 b/doc/README.ext4
index b3ea8b776d4a5ddd19e7fd4d3b11a14e69d86150..9a2de5088b9a1ce14eae3902f6cd292a83cc4fcc 100644 (file)
--- a/doc/README.ext4
+++ b/doc/README.ext4
@@ -1,44 +1,57 @@
 This patch series adds support for ext4 ls,load and write features in uboot
 Journaling is supported for write feature.
 
+To enable support for the ext4 (and ext2) filesystem implementation,
+#define CONFIG_FS_EXT4
+
+If you want write support,
+#define CONFIG_EXT4_WRITE
+
 To Enable ext2 ls and load commands, modify the board specific config file with
 #define CONFIG_CMD_EXT2
+This automatically defines CONFIG_FS_EXT4 for you.
 
 To Enable ext4 ls and load commands, modify the board specific config file with
 #define CONFIG_CMD_EXT4
+This automatically defines CONFIG_FS_EXT4 for you.
 
 To enable ext4 write command, modify the board specific config file with
 #define CONFIG_CMD_EXT4
 #define CONFIG_CMD_EXT4_WRITE
+These automatically define CONFIG_FS_EXT4 and CONFIG_EXT4_WRITE for you.
+
+Also relevant are the generic filesystem commands,
+#define CONFIG_CMD_FS_GENERIC
+This does not automatically enable EXT4 support for you.
 
 Steps to test:
 
 1. After applying the patch, ext4 specific commands can be seen
    in the boot loader prompt using
-        UBOOT #help
+       UBOOT #help
 
-        ext4load- load binary file from a Ext4 file system
-        ext4ls  - list files in a directory (default /)
-        ext4write- create a file in ext4 formatted partition
+       ext4load- load binary file from a Ext4 file system
+       ext4ls  - list files in a directory (default /)
+       ext4write- create a file in ext4 formatted partition
 
 2. To list the files in ext4 formatted partition, execute
-        ext4ls <interface> <dev[:part]> [directory]
-        For example:
-        UBOOT #ext4ls mmc 0:5 /usr/lib
+       ext4ls <interface> <dev[:part]> [directory]
+       For example:
+       UBOOT #ext4ls mmc 0:5 /usr/lib
 
 3. To read and load a file from an ext4 formatted partition to RAM, execute
-        ext4load <interface> <dev[:part]> [addr] [filename] [bytes]
-        For example:
-        UBOOT #ext4load mmc 2:2 0x30007fc0 uImage
+       ext4load <interface> <dev[:part]> [addr] [filename] [bytes]
+       For example:
+       UBOOT #ext4load mmc 2:2 0x30007fc0 uImage
 
 4. To write a file to a ext4 formatted partition.
-        a) First load a file to RAM at a particular address for example 0x30007fc0.
-        Now execute ext4write command
-        ext4write <interface> <dev[:part]> [filename] [Address] [sizebytes]
-        For example:
-        UBOOT #ext4write mmc 2:2 /boot/uImage 0x30007fc0 6183120
-        (here 6183120 is the size of the file to be written)
-        Note: Absolute path is required for the file to be written
+       a) First load a file to RAM at a particular address for example 0x30007fc0.
+       Now execute ext4write command
+       ext4write <interface> <dev[:part]> [filename] [Address] [sizebytes]
+       For example:
+       UBOOT #ext4write mmc 2:2 /boot/uImage 0x30007fc0 6183120
+       (here 6183120 is the size of the file to be written)
+       Note: Absolute path is required for the file to be written
 
 References :
        -- ext4 implementation in Linux Kernel