[U-Boot] RFC USB composite devices

[Tom]

Remy Bohmer wrote:
> Hi,
> 
> 2009/9/29 Tom <Tom.Rix at windriver.com>:
>>>> The usb device and composite device support seems to be entirely based on
>>>> usbtty.Is there a newer interface that needs some help bringing to the
>>>> mainline? Else, ideas on how to do this cleanly ?
>>> Well, I have the complete Linux gadget layer as USB device layer in
>>> U-boot. Maybe this helps. I have not found the time yet to push it
>>> forward...
>>> It can be found in the u-boot-usb branch.
>>> (http://git.denx.de/?p=u-boot/u-boot-usb.git;a=shortlog;h=refs/heads/cdc)
>>>
>>> Remy
>> Thanks!
>> I have taken a look at this.
>> It looks like the reference is an ethernet over usb device on at91.
>> I have an at91sam9g20-ek. Is this compatibly with your work?
>> Else I will just jump in with omap.
> 
> Yes, it is first implemented on the at91sam9261, if the sam9g20 has
> the same USB device peripheral, it should work as well (if configured)
> But it should not be so difficult to adapt it for the omap as long as
> there is a linux udc driver for it. Using it on at91sam9g20-ek might
> give you an idea how it works and if it is usable for you. The gadget
> layer is from linux 2.6.27 btw.

The interface looks well documented enough that I am going to just jump
in with omap.  I will use the omap usb device driver, i just submitted, 
as the driver.  I am adding #ifdef's to keep the old device interface. 
So I can verifiy I haven't messed up the usb state machine and to serve 
as an example for other existing usb devices to be ported over.

The ethernet over usb gadget will be useful for Beagle as it doesn't 
have one.

> 
>> Are there any missing pieces that I should be aware of?
> 
> I think not, the branch is complete as it is, and it works for the at91sam9261.
> I kept this branch updated to mainline plus CDC patches...
> 

Once I get past seeing the ethernet gadget work on Beagle, I think
we should move this into the mainline.

Tom