Hi Ram,

On 07/30/2015 07:49 AM, Kallumari Nagaraja Rao, RammohanX wrote:
> Hi Denis,
>
> Can't we use the existing ofono UBLOX driver to work with serial interfaces instead of USB interface ?
>

Not in its current form, no.

USB devices generally come pre-multiplexed.  What this means is that 
they expose multiple AT ports (e.g. ttyACM1, ttyACM2, etc).  oFono 
requires two if the modem uses PPP (which the ublox driver is currently 
using).  This is necessary as a second control port is needed for 
control while another is being occupied by PPP packets.

Serial devices use a single serial port and will require some form of 
multiplexing in order to enable properly.  Most support 07.10/27.010 
multiplexing via AT+CMUX.

Your options are to write a new modem driver for your device, or extend 
the ublox driver to handle serial devices.  Refer to plugins/ifx.c or 
plugins/calypso.c for an example of a driver that uses multiplexing.

Regards,
-Denis