README: Document current DFU CONFIG options

Add documentation for the current DFU config options.  DFU is a standard
USB device class so more information is available from usb.org

Signed-off-by: Tom Rini <trini@ti.com>

diff --git a/README b/README
index 57010161f57f5a719430b06a64b75fd27980b16d..f7f41bc7ed0e50b8757800c96976c115c0b95f65 100644 (file)
--- a/README
+++ b/README
@@ -1344,6 +1344,19 @@ The following options need to be configured:
                        CONFIG_SH_MMCIF_CLK
                        Define the clock frequency for MMCIF
 
+- USB Device Firmware Update (DFU) class support:
+               CONFIG_DFU_FUNCTION
+               This enables the USB portion of the DFU USB class
+
+               CONFIG_CMD_DFU
+               This enables the command "dfu" which is used to have
+               U-Boot create a DFU class device via USB.  This command
+               requires that the "dfu_alt_info" environment variable be
+               set and define the alt settings to expose to the host.
+
+               CONFIG_DFU_MMC
+               This enables support for exposing (e)MMC devices via DFU.
+
 - Journaling Flash filesystem support:
                CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
                CONFIG_JFFS2_NAND_DEV