Issue with SIM7100E pcie module

Hi,

For one of the IOT project, I am using SIM7100E mini PCIe module. I am using connman(1.36) and ofono(1.26) to establish cellular connection. I am seeing that the same module is sometimes identified as gobi and sometimes as sim7100 by ofono. Attached the logs for reference:

# lsusb
Bus 003 Device 008: ID 1e0e:9001 Qualcomm / Option

# /usr/lib/ofono/test/list-modems
[ /sim7100_0 ]
    Type = hardware
    Emergency = 0
    Model = SIMCOM_SIM7100E
    Serial = 866802021517042
    Interfaces = org.ofono.SmartMessaging org.ofono.PushNotification org.ofono.MessageManager org.ofono.NetworkRegistration org.ofono.ConnectionManager org.ofono.Phonebook org.ofono.CallMeter org.ofono.SupplementaryServices org.ofono.CallBarring org.ofono.CallSettings org.ofono.CallForwarding org.ofono.MessageWaiting org.ofono.AllowedAccessPoints org.ofono.VoiceCallManager org.ofono.SimManager
    SystemPath = /sys/devices/soc0/soc/30800000.aips-bus/30b30000.usb/ci_hdrc.2/usb3/3-1/3-1.3
    Manufacturer = SIMCOM INCORPORATED
    Online = 1
    Powered = 1
    Features = sms net gprs ussd sim
    Revision = 4534B06SIM7100E
    Lockdown = 0

# /usr/lib/ofono/test/list-modems
[ /gobi_0 ]
    Serial = 866802021517042
    Interfaces = org.ofono.LongTermEvolution org.ofono.SmartMessaging org.ofono.PushNotification org.ofono.MessageManager org.ofono.NetworkRegistration org.ofono.ConnectionManager org.ofono.SupplementaryServices org.ofono.NetworkMonitor org.ofono.RadioSettings org.ofono.MessageWaiting org.ofono.AllowedAccessPoints org.ofono.SimManager org.ofono.VoiceCallManager
    Online = 1
    Emergency = 0
    Features = sms net gprs ussd rat sim
    Revision = M9615A-CETWTBZM-6.0.15255  1  [May 13 2016 01:00:00]
    Type = hardware
    Manufacturer = QUALCOMM INCORPORATED
    Powered = 1
    Model = SIMCOM_SIM7100E
    SystemPath = /sys/devices/soc0/soc/30800000.aips-bus/30b30000.usb/ci_hdrc.2/usb3/3-1/3-1.3
    Lockdown = 0

I looked into the source code of ofono. Gobi and sim7100 both are implemented as plugin. From the source code (plugins/udevng.c) it looks like the module should use sim7100 plugin. But it is not always the case for me.

{ "gobi", "qmi_wwan" },
{ "gobi", "qcserial" },
{ "sim7100", "option", "1e0e", "9001" },

Further if the module is identified as gobi, I am able to connect to the internet. If it is identified as sim7100, the module gets disconnected and connected again (reset) whenever I am trying to activate the context.

May I know what is the issue here and any idea on how to fix this issue will be helpful.

Mit freundlichen Grüßen / Best regards

Vinothkumar Eswaran
BEG-PT/PJ-EL

Hi,

So it seems that the device provides interfaces that attach to "option" and "qmi_wwan" drivers. The ordering of these interfaces being announced by the kernel isn't defined, so ofono ends up picking the driver that matches the first interface that it recognizes... hence you get sometimes sim7100 and sometimes gobi.

You'll want to add something like this:

{ "sim7100",        "option",             "1e0e", "9001"  },
{ "sim7100",        "qmi_wwan",           "1e0e", "9001"  },

With that you'll be prevented from being directed to the gobi driver. After that you'll need to fiddle a bit with setup_sim7100 in order to get it to pass the qmi interfaces through to the gobi driver. See setup_quectelqmi for something similar.

Hope that helps,
Jonas