Date: Mon, 08 Sep 2014 23:18:38 +0200 From: Hans Petter Selasky <hps@selasky.org> To: Ian Lepore <ian@FreeBSD.org> Cc: freebsd-hackers@freebsd.org Subject: Re: What to do if USB stack seems dead Message-ID: <540E1D2E.3020401@selasky.org> In-Reply-To: <1410208808.1150.406.camel@revolution.hippie.lan> References: <1455331.JKPkSxLmbq@quad> <540B7AC4.9060504@selasky.org> <1410208808.1150.406.camel@revolution.hippie.lan>
next in thread | previous in thread | raw e-mail | index | archive | help
On 09/08/14 22:40, Ian Lepore wrote: > On Sat, 2014-09-06 at 23:21 +0200, Hans Petter Selasky wrote: >> 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 > > What does that mean, "is not closed"? You mean if I have any usb-serial > adapter tty device open, other device insert/remove events aren't > handled? > > Or that if a usb-serial device is removed while the device is open, that > prevents other insert/remove events? > > -- Ian Yes, because we need to wait for some refcounting inside the TTY layer at detach when the TTY device is open at detach. It is not a USB stack problem. --HPS
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?540E1D2E.3020401>