On Wednesday 20 September 2006 10:58 am, Harald Welte wrote:

> > When a control-out transfer takes, the host controller sends a SETUP
> > packet followed by as many OUT/DATA packets as necessary to transfer the
> > data, but no zero-length OUT/DATA.  There is a zero-length IN packet to
> > terminate the transfer (the "status stage"), but that's present regardless
> > of the amount of data.
> 
> This really solves my problem.  One fundamental problem (at least given
> the SAM7 register set) remains: I have no indication to decide which of
> the data OUT packets was the last, and when the device should return the
> status stage IN packet.

The at91_udc driver should work on those at91sam7 parts, and I think
some uClinux folk have done just that.

As Alan commented, once you get the IN packet, you know no more OUT DATA
segments will be arriving.  Control transfers are always a bit convoluted
to follow in the code, but that's how at91_udc does it ...

- Dave

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