Hi,

I want to know if the cdc branch of the uboot-usb is a working one

It is a working one, I use it myself already a long time, but it needs some rework to make it mainline ready/clean, I have not put much time in it lately...

or still in development. there were some compilation error when I enable the

What kind of error?

CONFIG_USB_ETHER and GADGET_AT91. I am compiling it for at91sam9263-ek.

The tree is ready for the 9261-ek so the 9263-ek is a close match, but it might lack some configuration code.

But also paralelly i brought it to the main tree as it is needed for me in my work. and It compiles fine. I disabled the CONFIG_MACB  in the header file and after that I dont know what should I do to enable the usb0. Can you please give me some idea how to bring up the usb ethernet interface in term of testing the functionality. in my host machine there is no changes in dmesg and lsusb. Any help would be great.

It behaves like any other network adapter in U-boot. It will only be brought up and thus visible to the host if some network action is active, like e.g. a tftp get/put command. Once that action is completed, the connection is dropped again, and the pullup to the host deactivated what makes the device invisible for the host. If there are more network drivers available you must first make the usb0 the active adapter.

Kind regards,

Remy