I have youyeetoo R1 installed with LTE modem but it unable to detect it.
root@R1:~# sudo modem-manager.mmcli -L
No modems were found
root@R1:~# sudo dmesg | grep -i -E 'modem|wwan|qmi|cdc|mbim'
[ 1.922467] usbcore: registered new interface driver cdc_ether
[ 1.922489] usbcore: registered new interface driver cdc_subset
[ 1.922516] usbcore: registered new interface driver cdc_ncm
[ 1.922526] usbcore: registered new interface driver qmi_wwan
[ 2.079008] usbcore: registered new interface driver cdc_acm
[ 2.079012] cdc_acm: USB Abstract Control Model driver for USB modems and ISDN adapters
[ 2.079025] usbcore: registered new interface driver cdc_wdm
[ 2.079337] usbserial: USB Serial support registered for GSM modem (1-port)
[ 2.079443] usbserial: USB Serial support registered for Qualcomm USB modem
[ 2.079468] usbserial: USB Serial support registered for Sierra USB modem
[ 2.808130] 5cdc b40008c1 aa0103fa aa0103e0 97fa9cd8 11000418 52800281 2a184038 f9404363
Do you have any guide for using LTE with this model ?