I appreciate the responses. The resolution turned out to be that when I enabled serial support in the kernel and in the OpenEmbedded recipe for ModemManager, I didn't also explicitly enable QMI in the ModemManager build. Adding that, I believe the parameters OE sent to configure were:
--with-at-command-via-dbus --with-qmi,--without-qmi,libqmi (The OE recipe I'm working with is a monkey-copy of an earlier recipe, not an official one; we're still using Yocto's Dunfell release at present.) I have another issue encountered during reboot, but I'll post about that after I have done some research. Bruce Johnson Chantilly, Virginia USA On 19/04/2024 12:39, Bruce Johnson wrote: 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