Dave:

Here are the results from a few tests of my net2280 card, fresh as of this 
afternoon.

(1) Testing with a Beagle analyzer showed that when running at full-speed,
the net2280 always finishes a transfer on ep0 by NAKing the first
status-stage transaction and sending the expected packet the second time.  
This is odd because the transfers were running without FSBR, so there was
only one transaction per frame.  The net2280 therefore had a millisecond
to prepare for finishing the transfer, which should have been plenty of
time.  This was all stuff like descriptor fetches, nothing fancy.

(2) Editing zero.c to set various string descriptors to exactly 31 bytes
showed that the net2280 did not respond correctly after all the data had
been sent.  A Get-String-Descriptor request for 255 bytes transferred 64
bytes in the first Data packet, and after that the net2280 NAKed all
further IN packets until the transfer timed out.  I verified this directly
using the Beagle analyzer at full speed; at high speed usbmon showed the
same results.

(3) After timing out on the Serial number descriptor transfer, Linux does
a Get-Device-Status, which is a 2-byte transfer.  The data was transferred
correctly, but again the net2280 NAKed the status stage until the transfer
timed out.  Oddly enough, when I changed the Manufacturer string (which is
fetched immediately before the Serial number string) to be 31 bytes long
so that it timed out, and made the Serial number either 30 or 32 bytes,
the Serial number transfer proceeded correctly.

Clearly something is not working right.  However I have no idea where to 
look or what to change in the driver.

Alan Stern



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