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Subject: Re: USB ppbus?
To: George Mitchell <george+freebsd@m5p.com>, freebsd-hackers@freebsd.org
References: <35e62a59-556a-68bf-3b9d-017108f12f38@m5p.com>
From: Hans Petter Selasky <hps@selasky.org>
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Date: Tue, 20 Dec 2016 18:57:50 +0100
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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