[U-Boot] [PATCH 1/2] usb: ci_udc: allow multiple buffer allocs per ep

[Marek Vasut]

On Thursday, June 12, 2014 at 07:42:55 PM, Stephen Warren wrote:
> On 06/12/2014 11:30 AM, Marek Vasut wrote:
> > On Thursday, June 12, 2014 at 05:55:40 PM, Stephen Warren wrote:
> > [...]
> > 
> >>>> I'm slightly confused by this log. Do you have 2 boards running
> >>>> U-Boot, one running the USB controller in device mode, and this is
> >>>> the log from some other board that's talking to that first board?
> >>> 
> >>> I have one board connect to a PC. The log shows two different errors
> >>> happening on the board. The first log shows a tftp command on the board
> >>> stopping with a timeout after receiving some packets. The second log
> >>> shows a tftp command on the same board throwing an error before
> >>> receiving any packet.
> >> 
> >> So U-Boot is running on the board, and the logs are from the board, i.e.
> >> you're running the "tftp" command in U-Boot on the board?
> >> 
> >> If so, I'm confused how ci_udc comes into play at all; doesn't "tftp"
> >> use the USB controller in host mode, whereas ci_udc is only used for
> >> device mode?
> > 
> > U-Boot CDC ethernet support, that's pretty normal mode of operation ;-)
> 
> Oh, so that makes U-Boot into a kind of virtual NIC where the packets
> don't go anywhere but U-Boot's internal network stack, and that feature
> runs in the background with the interactive shell still fully operation
> then?

Nah, it runs in the foreground. I think I wrote some short howto on this when I 
initially wanted to boast about it [1].

[1] http://www.denx-cs.de/?q=blogm28singlewiredebug

> All the USB device mode support I've used is a synchronous/blocking
> shell command (dfu, ums) rather than something that runs in the
> background, so I figured CDC Ethernet would work the same.

It's sync, blocking :)

> Perhaps I should try and get CDC Ethernet working... Can both
> CONFIG_USB_GADGET and CONFIG_USB_ETHER co-exist I wonder? Actually,
> U-Boot acting as a USB serial port running at the same time as dfu or
> ums would be more useful to me.

Check the link ;-)

Best regards,
Marek Vasut