How to use the RG255C with ModemManager and qmicli

Technical Subjects Driver
1

If anyone want to use the RG255C with the qmicli or the ModemManager, please do not try the qmi_wwan_q. Just use the native Linux driver. But you also need to add this

diff --git a/qmi_wwan.c b/qmi_wwan.c
index 554d4e2..3ce2723 100644
--- a/qmi_wwan.c
+++ b/qmi_wwan.c
@@ -1419,6 +1419,7 @@ static const struct usb_device_id products[] = {
        {QMI_QUIRK_SET_DTR(0x2c7c, 0x0191, 4)}, /* Quectel EG91 */
        {QMI_QUIRK_SET_DTR(0x2c7c, 0x0195, 4)}, /* Quectel EG95 */
        {QMI_FIXED_INTF(0x2c7c, 0x0296, 4)},    /* Quectel BG96 */
+       {QMI_FIXED_INTF(0x2c7c, 0x0316, 3)},    /* Quectel RG255C */
        {QMI_QUIRK_SET_DTR(0x2cb7, 0x0104, 4)}, /* Fibocom NL678 series */
        {QMI_FIXED_INTF(0x0489, 0xe0b4, 0)},    /* Foxconn T77W968 LTE */
        {QMI_FIXED_INTF(0x0489, 0xe0b5, 0)},    /* Foxconn T77W968 LTE with eSIM support*/
2

qmi_wwan.zip (49.2 KB)

@Wilmes
Please try this one.

3

Please also add this in the script for ModemManager.

/lib/udev/rules.d/77-mm-quectel-port-types.rules

# Quectel RG255C
#  ttyUSB0 (if #0): QCDM/DIAG port
#  ttyUSB1 (if #1): GPS data port
#  ttyUSB2 (if #2): AT primary port
ATTRS{idVendor}=="2c7c", ATTRS{idProduct}=="0316", ENV{.MM_USBIFNUM}=="00", SUBSYSTEM=="tty", ENV{ID_MM_PORT_TYPE_QCDM}="1"
ATTRS{idVendor}=="2c7c", ATTRS{idProduct}=="0316", ENV{.MM_USBIFNUM}=="01", SUBSYSTEM=="tty", ENV{ID_MM_PORT_TYPE_GPS}="1"
ATTRS{idVendor}=="2c7c", ATTRS{idProduct}=="0316", ENV{.MM_USBIFNUM}=="02", SUBSYSTEM=="tty", ENV{ID_MM_PORT_TYPE_AT_PRIMARY}="1"
4

By the way…I noticed that the product description claims that this module features a “PCIE2.0 Port for Wi-Fi and Bluetooth” - what does this mean?
Means this module is capable to be used as Wifi and BT device? So, in device manager there would be a section wifi and BT for this module?

5

The RG255C can connect with a WIFI or Bluetooth Chip.
Quectel also provide some WIFI module such as FC64E and it can work with the RG255C.

6

Ah ok thanks for clarification. I am looking for an affordable 5G Combo Modem or Smart Modem für Cellular, GNSSm Wifi6 and BT5 in M.2 form factor but it seems such device does noct exist

7

As I know, for such module you might need the Smart module such SG885(based on Qualcomm QCS8550) with Android 13.
But for personal or individual customer, Quectel would not provide the SDK.

8

I followed the above instructions and I have the following output on the ModemManager side. I have two main problems here;

  • In this output, signal quality always shows 0%. When I test with AT commands, I can see the signal strength at normal level.
    -Another question is that the gps data is not fixed even though I wait for long periods of time.
    Can you help me with these problems?
9

It still need a customized version to support the qmicli and gps data for mmcli.

10

So, how can i customized? Is there any documentation about this?

11

Please contact with the sale.
For normal version, some QMI are not supported.