[BUG]Telit FN990A28 支持与qmi/mbim拨号问题

[duceman495]

描述问题
Telit FN990A28 支持不完整，有两个问题：

1. 识别：modem_support.json 只登记了 fn990a40，没有 fn990a28（FN990 家族有 A40/A28 两个型号，AT 命令集和 USB composition 完全相同），导致 FN990A28 的 AT+CGMM 返回 "FN990A28" 归一化后查不到 profile，扫描器报 modem profile not matched。
2. 拨号：补上 profile 识别成功后，QMI 拨号一直失败。FN990 在 5G SA 下网络自动建立默认 PDU 会话（模组已拿到运营商 IP），quectel-CM-M 再 requestSetupDataCall 新建同配置会话被拒，报 call_end_reason_verbose = 241（INTERFACE_IN_USE_CONFIG_MATCH），无限重试。MBIM 模式同样失败（mbim_set_connect Status=2）。RNDIS 模式（#USBCFG=0 + 自带自动建链）才能通。

Describe the Issue
Telit FN990A28 support is incomplete:

1. Recognition: modem_support.json only has fn990a40, not fn990a28 (the FN990 family has A40/A28 variants with identical AT command sets and USB compositions), so FN990A28 fails to match → modem profile not matched.
2. Dialing: after recognition is fixed, QMI dialing keeps failing. On 5G SA the FN990 auto-establishes the default PDU session (modem already has a carrier IP), and quectel-CM-M's requestSetupDataCall is rejected with call_end_reason_verbose = 241 (INTERFACE_IN_USE_CONFIG_MATCH), retrying forever. MBIM mode fails the same way (Status=2). Only RNDIS mode works.

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复现方法

1. 模组保持默认 QMI 组合（AT#USBCFG=1，PID 1bc7:1070）。
2. QModem 识别到模组（识别修复后 name=fn990a28）并启用拨号（apn=3gnet，force_set_apn=1）。
3. 观察拨号日志持续报 241，wwan0 无载波、拿不到 IP，接口一直 down。

Steps to Reproduce

1. Keep the modem in QMI composition (AT#USBCFG=1, PID 1bc7:1070).
2. After recognition is fixed (name=fn990a28), enable dialing (apn=3gnet, force_set_apn=1).
3. The dial log keeps showing 241; wwan0 has no carrier and never gets an IP.

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期望行为
quectel-CM-M 应检测到已存在的默认 PDU 会话并复用（查询 current settings / 直接把 IP 绑到接口），而不是永远 requestSetupDataCall 新建一条。

Expected Behavior
quectel-CM-M should detect and reuse the already-active default PDU session instead of always issuing a new requestSetupDataCall.

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屏幕截图
（无 / N/A）

Screenshots

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日志信息
Log Information

模组配置 (Module Configuration)

# uci show qmodem
qmodem.6_1=modem-device
qmodem.6_1.path='/sys/bus/usb/devices/6-1/'
qmodem.6_1.data_interface='usb'
qmodem.6_1.enable_dial='1'
qmodem.6_1.pdp_type='ipv4v6'
qmodem.6_1.metric='11'
qmodem.6_1.name='fn990a28'
qmodem.6_1.manufacturer='telit'
qmodem.6_1.platform='qualcomm'
qmodem.6_1.suggest_pdp_index='1'
qmodem.6_1.at_port='/dev/ttyUSB3'
qmodem.6_1.apn='3gnet'
qmodem.6_1.force_set_apn='1'
qmodem.6_1.modes='mbim' 'rndis' 'qmi' 'ecm'
qmodem.6_1.valid_at_ports='/dev/ttyUSB3' '/dev/ttyUSB4' '/dev/ttyUSB2'

网络配置 (Network Configuration)

# uci show network（QMI 模式下 device 为 wwan0，RNDIS 模式下为 eth2）
network.wan=interface
network.wan.device='eth0'
network.wan.proto='dhcp'
network.6_1=interface
network.6_1.modem_config='6_1'
network.6_1.proto='dhcp'
network.6_1.defaultroute='1'
network.6_1.metric='11'
network.6_1.device='eth2'
network.6_1v6=interface
network.6_1v6.proto='dhcpv6'
network.6_1v6.device='@6_1'

系统日志 (System Logs)

# 识别（修复前报 profile not matched，修复后正常）
modem_scand: slot=6-1 type=usb modem profile not matched     # 修复前
modem_scand: added modem section=6_1 name=fn990a28 type=usb ports=3 valid=3   # 修复后

# QMI 拨号日志 /var/run/qmodem/6_1_dir/dial_log（核心证据，无限重试 241）
requestGetProfile[pdp:1 index:1] 3gnet///0/IPV4V6
requestSetProfile[pdp:1 index:1] 3gnet///0/IPV4
requestRegistrationState2 MCC: 460, MNC: 1, PS: Attached, DataCap: 5G_SA
requestSetupDataCall QMUXResult = 0x1, QMUXError = 0xe
call_end_reason is 1
call_end_reason_type is 2
call_end_reason_verbose is 241
try to requestSetupDataCall 5 second later
requestSetupDataCall QMUXResult = 0x1, QMUXError = 0xe
call_end_reason_verbose is 241
try to requestSetupDataCall 10 second later
...

# AT 侧证据：会话其实已经自动建立、拿到 IP
AT+C5GREG?     -> +C5GREG: 0,1            （5G 已注册回家网）
AT+CGACT?      -> +CGACT: 1,1             （context 1 已激活）
AT+CGCONTRDP=1 -> +CGCONTRDP: 1,1,"3gnet","10.46.243.196", 网关 10.46.243.197, DNS 202.102.224.68
AT+CGACT=0,1   -> ERROR                   （always-on 会话 UE 侧关不掉）

# MBIM 模式（#USBCFG=2）同样失败
mbim_set_connect(onoff=1, sessionID=0)
< Status = 2
< ActivationState = Deactivated (3)
mbim_set_connect:2023 err=0, Status=2

内核日志 (Kernel Logs)

# QMI 模式（0x1070）下接口 2 绑定 qmi_wwan_q
qmi_wwan_q 6-1:1.2: cdc-wdm0: USB WDM device
qmi_wwan_q 6-1:1.2 wwan0: register 'qmi_wwan_q' at usb-xhci-hcd.1.auto-1

# option 驱动绑定串口
option 6-1:1.0: GSM modem (1-port) converter detected  -> ttyUSB0
option 6-1:1.4: GSM modem (1-port) converter detected  -> ttyUSB1
option 6-1:1.5: GSM modem (1-port) converter detected  -> ttyUSB2
option 6-1:1.6: GSM modem (1-port) converter detected  -> ttyUSB3
option 6-1:1.7: GSM modem (1-port) converter detected  -> ttyUSB4

USB设备信息 (USB Devices)

# QMI 模式（默认，#USBCFG=1）
Bus 006 Device 002: ID 1bc7:1070 Telit Wireless Solutions FN990
    |__ Port 001: Dev 002, If 0, Driver=option
    |__ Port 001: Dev 002, If 1, Driver=[none]      (ADB)
    |__ Port 001: Dev 002, If 2, Driver=qmi_wwan_q  (RmNet/QMI)
    |__ Port 001: Dev 002, If 3, Driver=option      (NMEA)
    |__ Port 001: Dev 002, If 4, Driver=option      (MODEM/AT)
    |__ Port 001: Dev 002, If 5, Driver=option      (MODEM)
    |__ Port 001: Dev 002, If 6, Driver=option      (AUX)

# 当前 workaround：RNDIS 模式（#USBCFG=0）
Bus 006 Device 006: ID 1bc7:1072 Telit Wireless Solutions FN990
    |__ Port 001: Dev 006, If 0, Driver=rndis_host
    |__ Port 001: Dev 006, If 1, Driver=rndis_host
    |__ Port 001: Dev 006, If 2, Driver=option
    |__ Port 001: Dev 006, If 3, Driver=[none]
    |__ Port 001: Dev 006, If 4, Driver=option
    |__ Port 001: Dev 006, If 5, Driver=option
    |__ Port 001: Dev 006, If 6, Driver=option
    |__ Port 001: Dev 006, If 7, Driver=option

模组扫描 (Module Scanning)

# /usr/share/qmodem/modem_scan.sh scan
{"code":0,"message":"queued"}

# 扫描结果（logread）
modem_scand: added modem section=6_1 name=fn990a28 type=usb ports=3 valid=3