Quectel BG96 in QMI: mismatched allowed mode settings
1. This is the initial state. Both MM and AT-cmd shows the 4G comes before 2G.
# mmcli -m 1 --command="AT+QCFG=\"nwscanseq\""
response: '+QCFG: "nwscanseq",020301'
# mmcli -m 1 --command="AT+QCFG=\"nwscanmode\""
response: '+QCFG: "nwscanmode",0'
# mmcli -m 1
--------------------------------
General | dbus path: /org/freedesktop/ModemManager1/Modem/1
| device id: 37db16a6a9ce688c0e0f3390071bd0ae24c2bdce
--------------------------------
Hardware | manufacturer: Quectel
| model: 0
| firmware revision: BG96MAR02A11M1G
| carrier config: default
| h/w revision: 10000
| supported: gsm-umts, lte
| current: gsm-umts, lte
| equipment id: 868963043820877
--------------------------------
System | device: /sys/devices/platform/ahb/500000.ehci/usb1/1-2
| drivers: qmi_wwan, option1
| plugin: Quectel
| primary port: cdc-wdm0
| ports: cdc-wdm0 (qmi), ttyUSB0 (qcdm), ttyUSB2 (at), wwan0 (net),
| ttyUSB1 (gps), ttyUSB3 (at)
--------------------------------
Status | lock: sim-pin2
| unlock retries: sim-pin (3), sim-puk (10), sim-pin2 (3), sim-puk2 (10)
| state: connected
| power state: on
| access tech: lte
| signal quality: 96% (recent)
--------------------------------
Modes | supported: allowed: 2g; preferred: none
| allowed: 4g; preferred: none
| allowed: 2g, 4g; preferred: 4g
| allowed: 2g, 4g; preferred: 2g
| current: allowed: 2g, 4g; preferred: 4g
--------------------------------
Bands | supported: egsm, dcs, pcs, g850, eutran-1, eutran-2, eutran-3,
| eutran-4, eutran-5, eutran-8, eutran-12, eutran-13, eutran-17,
| eutran-18, eutran-19, eutran-20, eutran-26, eutran-28, eutran-39
| current: egsm, dcs, pcs, g850, eutran-1, eutran-2, eutran-3,
| eutran-4, eutran-5, eutran-8, eutran-12, eutran-13, eutran-17,
| eutran-18, eutran-19, eutran-20, eutran-26, eutran-28, eutran-39
--------------------------------
IP | supported: ipv4, ipv6, ipv4v6
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3GPP | imei: 868963043820877
| operator id: 26201
| operator name: TDG
| registration: home
--------------------------------
3GPP EPS | ue mode of operation: csps-2
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SIM | dbus path: /org/freedesktop/ModemManager1/SIM/1
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Bearer | dbus path: /org/freedesktop/ModemManager1/Bearer/3
2. Then I set the priority to 2G. Both MM and AT-cmd shows the 2G has now priority.
# mmcli -m 1 --set-allowed-modes='2g|4g' --set-preferred-mode='2g'
successfully set current modes in the modem
#
# mmcli -m 1 --command="AT+QCFG=\"nwscanseq\""
response: '+QCFG: "nwscanseq",010203'
3. Then I wanted to set the priority to 4G again. But could not do it with MM. AT comamnd shows the search sequence does not change. But the MM "thinks" the priority is already set back to 4G.
# mmcli -m 1 --set-allowed-modes='2g|4g' --set-preferred-mode='4g'
successfully set current modes in the modem
#
#
# mmcli -m 1 --command="AT+QCFG=\"nwscanseq\""
response: '+QCFG: "nwscanseq",010203'
--------------------------------
Modes | supported: allowed: 2g; preferred: none
| allowed: 4g; preferred: none
| allowed: 2g, 4g; preferred: 4g
| allowed: 2g, 4g; preferred: 2g
| current: allowed: 2g, 4g; preferred: 4gFrom https://lists.freedesktop.org/archives/modemmanager-devel/2021-November/008999.html