'port forced close' after failed ppp

[Dan Williams]

On Mon, 2017-03-06 at 15:35 +0000, colin.helliwell at ln-systems.com
wrote:
> I have MM hooked into a Mux driver which is presenting two virtual
> ports:
> one as the Primary, one for PPP. I'm attempting to fire up the
> data/PPP with
> --enable and --simple-connect=.
> 
> The PPP is failing, no doubt a problem with the config in that
> itself, but I
> have a couple of puzzlements:
> 
>  
> 
> MM is getting a "[src/mm-port-serial.c:942] common_input_available():
> (ttyMux1) unexpected port hangup!" . But I can't see in the source
> where the
> G_IO_HUP [?] would be originating - maybe a handshake signal on the
> port?

Correct.  Something (driver? modem? MM?) cleared DTR or RTS and caused
a serial port hangup.  Any chance you can instrument the MUX driver to
see if/when it calls tty_hangup() or tty_port_tty_hangup()?

To figure out if MM is involved, you can strace MM and see what
termio/tty operations it's doing, but usually this message is caused by
external things.

> I'm unable to retry - even with a '--simple-disconnect'/'
> --disable'/+retry,
> MM is giving "[src/mm-iface-modem-simple.c:221]
> connect_bearer_ready():
> Couldn't connect bearer: 'Couldn't connect: cannot keep data port
> open.Could
> not open serial device ttyMux1: it has been forced closed". Only
> restarting
> MM seems to get rid of this - should/could this error state get
> cleared down
> somehow?

Have you tried deleting the bearer and retrying the connection? 
Bearers don't get deleted automatically when they are terminated since
the connection manager might need to do some cleanup tasks, so that's
left to something external to MM.

Dan