Hi!

> > There's something very wrong with /dev/ttyUSB4 in recent kernels:
> > unsolicited incoming data from the modem are getting lost; I believe
> > it means also SMS notifications, but it is very easy to reproduce with
> > incoming call notifications.
> >
> > They just don't come.
> >
> > But if you keep pasting "AT" into minicom, they actually do.
> >
> > Of course... that means that trying to debug ofono is ... "interesting".
> >
> > I tried playing with
> > /sys/bus/platform/drivers/phy-mapphone-mdm6600/usb-phy\@1/power/control
> > files and timeouts, but could not get it to work.
> >
> > Any idea what could be wrong there?
> >
> > Is there easy way to disable power management for testing?
>
> I tried this... and it did not fix the problem :-(.

This does fix the problem:

# writing to ttyUSB3 eventually crashes the modem
# ttyUSB0 -- works w/o delay for an hour.
date
DEV=/dev/ttyUSB0
while test -e $DEV; do
  echo > $DEV
    sleep .3
      done
      date

...and with that:

1) AT commands work over ttyUSB4; yes that interface is far away from
fully compliant with the standard.

2) AFAICT, there are attempts at delivering SMS messages over QMI:

ofonod[16913]: src/network.c:ofono_netreg_strength_notify() strength
60

ofonod[16913]: QMI: < 01 89 00 80 05 01 04 00 00 01 00 7d 00 11 7a 00
...........}..z.
ofonod[16913]: QMI:   00 00 00 00 00 06 72 00 04 14 d0 d4 f2 7c fc 6e
......r......|.n
ofonod[16913]: QMI:   bf c5 69 76 19 00 00 02 80 10 81 61 21 80 68 d6
..iv.......a!.h.
ofonod[16913]: QMI:   b0 be ec ce 83 f4 e1 75 58 ef 4e af eb 2c 90 38
.......uX.N..,.8
ofonod[16913]: QMI:   cf 7e 83 ac e1 36 c8 9e 3f 97 dd 65 f9 db 1e 76
.~...6..?..e...v
ofonod[16913]: QMI:   97 41 ee f0 9c 5d 26 d7 d5 e9 71 1a a4 2e 93 dd
.A...]&...q.....
ofonod[16913]: QMI:   6f 79 58 ff b6 97 41 e8 f2 9c fd 06 c1 e5 6f 10
oyX...A.......o.
ofonod[16913]: QMI:   5c 9e 9e d3 eb 70 10 f9 0d 9a 87 db ef b7 78 ce
\....p........x.
ofonod[16913]: QMI:   ae a3 f3 3a d0 8d 96 8b c5 70
...:.....p
ofonod[16913]: QMI:     WMS_ind msg=1 len=125
[client=1,type=4,tid=0,len=137]
ofonod[16913]: QMI:        {type=17,len=122}
ofonod[16913]: drivers/qmimodem/sms.c:event_notify()
ofonod[16913]: drivers/qmimodem/sms.c:event_notify() ack_required 0
transaction id 0
ofonod[16913]: drivers/qmimodem/sms.c:event_notify() msg format 6 PDU
length 114
ofonod[16913]: src/sms.c:ofono_sms_deliver_notify() len 114 tpdu len
114
ofonod[16913]: src/sms.c:handle_deliver()
ofonod[16913]: src/sms.c:sms_dispatch()
ofonod[16913]: src/sms.c:sms_dispatch() dst -1 src -1
ofonod[16913]: Aborting (signal 11) [src/ofonod]
user@devuan:/my/ofono$

Best regards,
                                    Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html