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Date: Sat, 06 Sep 2014 23:21:08 +0200
From: Hans Petter Selasky <hps@selasky.org>
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To: Maxim V FIlimonov <che@bein.link>, freebsd-hackers@freebsd.org
Subject: Re: What to do if USB stack seems dead
References: <1455331.JKPkSxLmbq@quad>
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On 09/06/14 21:57, Maxim V FIlimonov wrote:
> Lately, I've been heavily experimenting with different USB devices (for
> instance, USB to TTL one, but that's another story), and at a moment I
> encountered that the system doesn't react on new USB devices connected. The
> connected devices work fine, though. The question is: what can I do in such a
> case if I don't want to reboot my box?
>

Hi,

If a TTY port is not closed, it will prevent other USB devices on that 
particular USB controller from enumerating.

--HPS