I have a question about using both QMI and the serial interface with
ModemManager.
I had little difficulty getting ModemManager's SimpleModem to connect to
T-Mobile (USA) using a Quectel EG25-G, but we found that modem wasn't
compatible with AT&T and/or a private APN used by one of our customers. We were
advised to use the Quectel EC25, and after engaging both Quectel and AT&T, we
were told that we need to insert the APN into the modem using an AT command,
AT+CGDCONT=1,"IPV4V6","mcm.com.attz". I had to tweak the kernel config and the
ModemManager build.
Mods:
* I built ModemManager 1.18.4 with --with-at-command-via-dbus.
* In the kernel config, I added USB Serial Converter support -> USB driver
for GSM and CDMA modems.
After I did this, the /dev/ttyUSB[1-4] files showed up, and I was able to issue
AT commands using ModemManager, but while the modem would sort-of connect with
SimpleModem's connect method -- I am getting a Bearer, and mmcli shows
"connected" -- I receive no IP address information from the carrier. Port wwan0
is showing up as "ignored". (mmcli output below)
The Quectel docs also said to patch the kernel a certain way to allow use of
serial and the QMI_WWAN driver, but wwan0 is still ignored.
Does anyone have any suggestions?
Thanks!
--
Bruce Johnson
Chantilly, Virginia
USA
--------------------------------
General | path: /org/freedesktop/ModemManager1/Modem/0
| device id: XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
--------------------------------
Hardware | manufacturer: Quectel
| model: EC25
| firmware revision: EC25AFFAR07A14M4G
| supported: gsm-umts, lte
| current: gsm-umts, lte
| equipment id: 359401089771197
--------------------------------
System | device: /sys/devices/pci0000:00/0000:00:15.0/usb1/1-4
| drivers: option, qmi_wwan
| plugin: quectel
| primary port: ttyUSB3
| ports: ttyUSB2 (gps), ttyUSB3 (at), ttyUSB4 (at),
wwan0 (ignored)
--------------------------------
Status | unlock retries: sim-pin (3), sim-puk (10), sim-pin2 (3),
sim-puk2 (10)
| state: connected
| power state: on
| access tech: lte
| signal quality: 60% (recent)
--------------------------------
Modes | supported: allowed: 2g, 3g, 4g; preferred: none
| current: allowed: 2g, 3g, 4g; preferred: none
--------------------------------
IP | supported: ipv4, ipv6, ipv4v6
--------------------------------
3GPP | imei: 3594010XXXXXXXX
| operator id: 310410
| operator name: AT&T
| registration: home
--------------------------------
3GPP EPS | ue mode of operation: csps-2
--------------------------------
SIM | primary sim path: /org/freedesktop/ModemManager1/SIM/0
--------------------------------
Bearer | paths: /org/freedesktop/ModemManager1/Bearer/0
