Date: Tue, 02 Nov 2004 15:39:25 +0200 From: Danny Braniss <danny@cs.huji.ac.il> To: Vicknesan AYADURAI <vicknesan@bigfoot.com> Cc: freebsd-usb@freebsd.org Subject: Re: Netgraph/mpd over USB modem problems Message-ID: <20041102133926.8FDB443D54@mx1.FreeBSD.org> In-Reply-To: Your message of Tue, 2 Nov 2004 14:03:16 %2B0100 (CET) .
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take a look at: http://lists.freebsd.org/pipermail/freebsd-bugs/2004-April/006379.html and http://groups.yahoo.com/group/freebsd-hackers/message/82879 > Hi Danny, > > Couldn't find: > > > look for a tcflush(..., TCIFLUSH) > > anywhere in /sys/dev/usb or /sys/netgraph, although there were some > other flush-related strings though. > > What did you do (to tcflush...) to fix it then? Not sure if the > problems are related, but I'm taking all offers at this stage... > > Thanks, > vick > > On Tue, 2 Nov 2004, Danny Braniss wrote: > > > look for a tcflush(..., TCIFLUSH) > > this did not work properly last time i checked, and screwed up the > > communicarions with a smart card usb reader. > > > > danny > > > > > Hi all, > > > > > > I've been battling this unsuccessfully for a while now, and hope > > > someone can shed some light on how to fix this. > > > > > > I'm trying to achieve a PPP dialup connection via a USB modem using > > > netgraph mpd. However there appears to be a problem between netgraph's > > > ng_tty node and /dev/ucom0, which I can't figure out/fix. > > > > > > The initial mpd chat script works fine, and AT commands successfully > > > establish a call between the local (USB) and remote modem. When DCD > > > comes up, the netgraph nodes kick in, and the netgraph chain (ng_ppp > > > -> ng_tty -> etc) is automatically (and correctly) formed. > > > > > > LCP packets are then sucessfully transmitted to the remote PPP host > > > via the USB port and modem. However, the subsequent responses arriving > > > at the local USB port, are not forwarded up the stack i.e., are not > > > received by the netgraph node(s). > > > > > > It's possible (although not completely confirmed) that this is somehow > > > related to the changing line-disciplines from TTYDISC (during the chat > > > phase) to NETGRAPHDISC (during LCP/PPP phase) when the netgraph nodes > > > are formed. > > > > > > I've verified that with the USB & serial modems (same modem actually): > > > > > > a. user-space PPP works on both /dev/cuaa0 and /dev/ucom0 > > > b. mpd works on /dev/cuaa0 but NOT /dev/ucom0 > > > > > > indicating that the individual components seem to work, but the > > > netgraph/USB combination has problems. The only difference between the > > > relevant serial and USB config files is: /dev/cuaa0 is changed to > > > /dev/ucom0 when switching from serial to USB. > > > > > > I've tested this on GENERIC FreeBSD versions 4.9R, 5.2.1R and > > > yesterday, on a new installation of 5.3-RC2 -- all without success. > > > All releases display seemingly identical behaviour, i.e., establishing > > > the call successfully, but not receiving incoming LCP frames. :-( > > > > > > Anyone have any experience running netgraph nodes with USB modems? > > > Even more generally, anyone know if netgraph is even _meant_ to work > > > with USB...? > > > > > > Desperately, > > > vick > > > _______________________________________________ > > > freebsd-usb@freebsd.org mailing list > > > http://lists.freebsd.org/mailman/listinfo/freebsd-usb > > > To unsubscribe, send any mail to "freebsd-usb-unsubscribe@freebsd.org" > > > > > > > > > > >
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