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Subject: Re: USB ppbus?
To: freebsd-hackers@freebsd.org
References: <35e62a59-556a-68bf-3b9d-017108f12f38@m5p.com>
 <930e14f6-d8a8-7f50-21b4-6e76c2057f31@selasky.org>
From: George Mitchell <george+freebsd@m5p.com>
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Date: Tue, 20 Dec 2016 13:15:02 -0500
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On 12/20/16 12:57, Hans Petter Selasky wrote:
> On 12/19/16 20:19, George Mitchell wrote:
>> I have a USB cable that terminates in a DB25 connector.  Inside is a
>> Prolific Technology PL2305:
>> http://prolificusa.com/files/ds_pl2305I_v1.0.pdf
>> It probes as a ulpt.  I would love if there existed such a thing as
>> a uppi device.  Does it sound possible to get to such a result by
>> extending the ppbus code to know about USB?  Or might it be simpler
>> to try to add the ppi ioctls (PPIGDATA, etc.) to ulpt.c?   -- George
> 
> Hi George,
> 
> There is currently no such thing. ulpt only provides a raw character
> device. The ppbus could possibly be implemented in userspace using libcuse.
> 
> --HPS
>
> [...]

Thanks for the response.  I think I could kludge the ioctls I want into
ulpt.c by learning more about the USB system works.  Possibly.  On a
good day.                                                    -- George