Well, it's not so easy. :)
I tried with a slight different initial sequence that tries to read 18
btes the first time (which is also legal if you restrict the maximum
packet size properly).  Then some other devices fail.
Making a quirk for it is tricky since the read that fails happens
as you try to read product and vendor ids.  And you need those ids to
look up the quirk.  But I'll give it some thought.

    -- Lennart

Rafal Boni wrote:

>In message <200308050929.11742.bradd@cat.co.za>, you write: 
>
>-> Hi,
>-> 
>-> I've got two different MultiTech USB devices. One is a PSTN MTA5634ZBA-USB 
>-> modem and the other is an ISDN MTA128ST-USB.
>-> 
>-> Now, running on NetBSD 1.6, the PSTN device is detected fine, no problems, b
>-> ut 
>-> the ISDN device gets the kernel to return the following message :
>-> 
>-> uhub0: device problem, disabling port 1
>-> 
>-> After sticking in a few printouts in the kernel I found (from what I can 
>-> see) when a new usb device is detected, the kernel expects a certain
>-> amount of transfers from the device, each of a certain size.
>-> 
>-> Now the PSTN device (the one that works) first transmits 8 bytes followed 
>-> by 18 bytes followed by a whole lot of other transfers of varying sizes. 
>-> I assume these all contain product, vendor info etc.. Now the ISDN device 
>-> transmits the 8 bytes for the first transfer but only seems to transmit 8 
>-> bytes for the second when the kernel is expecting 18 bytes.
>-> 
>-> Now what I'd like to know is if this is a quirk, and how exactly I can set 
>-> this up to properly detect the device.
>
>I've CC'ed Lennart, the NetBSD USB guru because this isn't the first time
>this sort of bug has been reported, and I've got a USB devices that also
>seem to suffer a similar fate.  Hopefully, Lennart will have a "oh, that's
>easy, just add this" answer :-)
>
>--rafal
>
>----
>Rafal Boni                                                     rafal@pobox.com
>  We are all worms.  But I do believe I am a glowworm.  -- Winston Churchill
>  
>