Setting 'legacy' property for GSM modem

Hi all,

I'm an Ofono N00b trying to figure out how configuration should happen, and I'm a bit stuck.

I'm trying to get a Novatel 3G modem configured, and seem to be quite close.

Using the nice OFONO_AT_DEBUG=1 switch, I can see what appears to be proper traffic to the point of connection:

     ofonod[1928]: Modem: > AT+CGDATA="PPP",1\r
     ofonod[1928]: Modem: < \r\nCONNECT HSDPA 3.6\r\n

And using strace, I see a bunch of writes following this:

         write(11, "~\377}#\300!}!}!} }$\321\265~", 17) = 17
         write(11, "\377}#\300!}!}!} }$\321\265~", 16) = 16

but no returned data.

If I contrast this with the same card in my laptop running Network Manager, I see that the "ATD*99**1#\r" string is used to make the connection:

     read(27, "\r\n+CGDCONT: 1,\"IP\",\"roam\",\"\",0,0"..., 1024) = 115
     read(27, 0x130f623, 1024)               = -1 EAGAIN (Resource
temporarily unavailable)
     write(27, "A", 1)                       = 1
     write(27, "T", 1)                       = 1
     write(27, "D", 1)                       = 1
     write(27, "*", 1)                       = 1
     write(27, "9", 1)                       = 1
     write(27, "9", 1)                       = 1
     write(27, "*", 1)                       = 1
     write(27, "*", 1)                       = 1
     write(27, "*", 1)                       = 1
     write(27, "1", 1)                       = 1
     write(27, "#", 1)                       = 1
     write(27, "\r", 1)                      = 1
     read(27, "\r\nCONNECT HSDPA 3.6\r\n", 1024) = 21

And data flows thereafter.

Reading the code, it appears that this form of dialing string is supported in Ofono, by using the 'legacy' option:

http://git.kernel.org/cgit/network/ofono/ofono.git/tree/gatchat/gsmdial.c#n397

Hi Eric,

Quoted 42 lines · Eric Nelson

Hi all,

I'm an Ofono N00b trying to figure out how configuration should happen, and I'm a bit stuck.

I'm trying to get a Novatel 3G modem configured, and seem to be quite close.

Using the nice OFONO_AT_DEBUG=1 switch, I can see what appears to be proper traffic to the point of connection:

     ofonod[1928]: Modem: > AT+CGDATA="PPP",1\r
     ofonod[1928]: Modem: < \r\nCONNECT HSDPA 3.6\r\n

And using strace, I see a bunch of writes following this:

         write(11, "~\377}#\300!}!}!} }$\321\265~", 17) = 17
         write(11, "\377}#\300!}!}!} }$\321\265~", 16) = 16

but no returned data.

If I contrast this with the same card in my laptop running Network Manager, I see that the "ATD*99**1#\r" string is used to make the connection:

     read(27, "\r\n+CGDCONT: 1,\"IP\",\"roam\",\"\",0,0"..., 1024) = 115
     read(27, 0x130f623, 1024)               = -1 EAGAIN (Resource
temporarily unavailable)
     write(27, "A", 1)                       = 1
     write(27, "T", 1)                       = 1
     write(27, "D", 1)                       = 1
     write(27, "*", 1)                       = 1
     write(27, "9", 1)                       = 1
     write(27, "9", 1)                       = 1
     write(27, "*", 1)                       = 1
     write(27, "*", 1)                       = 1
     write(27, "*", 1)                       = 1
     write(27, "1", 1)                       = 1
     write(27, "#", 1)                       = 1
     write(27, "\r", 1)                      = 1
     read(27, "\r\nCONNECT HSDPA 3.6\r\n", 1024) = 21

Quoted 8 lines

And data flows thereafter.

Reading the code, it appears that this form of dialing string is supported in Ofono, by using the 'legacy' option:

http://git.kernel.org/cgit/network/ofono/ofono.git/tree/gatchat/gsmdial.c#n397

gsmdial is just a developer / debug tool. If you think that this model will require using ATD*99 syntax, then you will need to set a vendor quirk. The only vendor that currently requires using ATD*99 instead of +CGDATA is SIMCOM.

Try the following as a quick test, change plugins/novatel.c post_sim():
to do
gc = ofono_gprs_context_create(modem,
OFONO_VENDOR_SIMCOM_SIM900, "atmodem", data->modem);

and see if that solves your problem. We have tested several Novatel modems and they seem to work just fine with +CGDATA, but you may have one that we have not tested.