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*/