Let's get the MC7455 working in MiFi!

I’ve been doing a lot of research over the past day, and I think this may be the right answer. I am not a Linux guy, so I am admittedly struggling.

What I have found is references to a “Direct IP” approach that this card uses and then something else about maybe needing a 4.5 kernel for QMI?

I guess I thought that it would work using old-style modem mode, but the com port drivers don’t load.

The following Sierra packages are installed by default:
kmod-usb-net-sierrawireless 4.4.92-1
kmod-usb-serial-sierrawireless 4.4.92-1

Okay, I discovered that this modem uses the qcserial driver. Once I installed that, the com ports are being setup as /dev/ttyUSB0 - 2.

The GLInet GUI does does not see them though, and I cannot get a connection even if I set them up manually in the network connections screen.

Any ideas on what to try next?

Also, really excited about the x750. Any chance you could support Sierra modems out of the box on that one? Or partner with the ROOTER Project to support the GL Mifi products?

Do you mean that there is ttyUSB0 to 2 but the UI cannot configure that?

so, still old question, can you set up in QMI mode? QMI is not tethering.

Alright. Here is where I am at.

I got the com ports working and they are now visible to the GL-Inet webpage.

I setup a remote logging server to make gathering logs easier. This is what I am getting from the connection attempt now:

6/5/2018 11:49 AM Notice 192.168.88.1 Interface ‘modem’ is setting up now
6/5/2018 11:49 AM Info 192.168.88.1 AP Ok=0
6/5/2018 11:49 AM Info 192.168.88.1 network(caIfnames) = wan wan6 wwan modem tethering
6/5/2018 11:49 AM Info 192.168.88.1 STA Ok=1
6/5/2018 11:49 AM Info 192.168.88.1 Scan and fixing the problems
6/5/2018 11:49 AM Info 192.168.88.1 bIsAutoRepeater = 0
6/5/2018 11:49 AM Info 192.168.88.1 Get Default wifi…enabled.
6/5/2018 11:49 AM Info 192.168.88.1 check wpa runing =
6/5/2018 11:49 AM Info 192.168.88.1 AP-Only Mode!
6/5/2018 11:49 AM Notice 192.168.88.1 modem (5237):
6/5/2018 11:49 AM Notice 192.168.88.1 pppd 2.4.7 started by root, uid 0
6/5/2018 11:49 AM Info 192.168.88.1 abort on (BUSY)
6/5/2018 11:49 AM Info 192.168.88.1 abort on (NO CARRIER)
6/5/2018 11:49 AM Info 192.168.88.1 abort on (ERROR)
6/5/2018 11:49 AM Info 192.168.88.1 report (CONNECT)
6/5/2018 11:49 AM Info 192.168.88.1 timeout set to 10 seconds
6/5/2018 11:49 AM Info 192.168.88.1 send (AT&F^M)
6/5/2018 11:49 AM Info 192.168.88.1 expect (OK)
6/5/2018 11:49 AM Info 192.168.88.1 AT&F^M^M
6/5/2018 11:49 AM Info 192.168.88.1 OK
6/5/2018 11:49 AM Info 192.168.88.1 – got it
6/5/2018 11:49 AM Info 192.168.88.1 send (ATE1^M)
6/5/2018 11:49 AM Info 192.168.88.1 expect (OK)
6/5/2018 11:49 AM Info 192.168.88.1 ^M
6/5/2018 11:49 AM Info 192.168.88.1 ATE1^M^M
6/5/2018 11:49 AM Info 192.168.88.1 OK
6/5/2018 11:49 AM Info 192.168.88.1 – got it
6/5/2018 11:49 AM Info 192.168.88.1 send (AT+CGDCONT=1,““IP””,““epc.tmobile.com””^M)
6/5/2018 11:49 AM Info 192.168.88.1 timeout set to 30 seconds
6/5/2018 11:49 AM Info 192.168.88.1 expect (OK)
6/5/2018 11:49 AM Info 192.168.88.1 ^M
6/5/2018 11:49 AM Info 192.168.88.1 AT+CGDCONT=1,““IP””,““epc.tmobile.com””^M^M
6/5/2018 11:49 AM Info 192.168.88.1 OK
6/5/2018 11:49 AM Info 192.168.88.1 – got it
6/5/2018 11:49 AM Info 192.168.88.1 send (ATD991#^M)
6/5/2018 11:49 AM Info 192.168.88.1 expect (CONNECT)
6/5/2018 11:49 AM Info 192.168.88.1 ^M
6/5/2018 11:49 AM Info 192.168.88.1 ATD
99
**1#^M^M
6/5/2018 11:49 AM Info 192.168.88.1 CONNECT
6/5/2018 11:49 AM Info 192.168.88.1 – got it
6/5/2018 11:49 AM Info 192.168.88.1 send ( ^M)
6/5/2018 11:49 AM Info 192.168.88.1 Serial connection established.
6/5/2018 11:49 AM Info 192.168.88.1 [ 705.286126] 3g-modem: renamed from ppp0
6/5/2018 11:49 AM Info 192.168.88.1 Using interface 3g-modem
6/5/2018 11:49 AM Notice 192.168.88.1 Connect: 3g-modem <–> /dev/ttyUSB2
6/5/2018 11:49 AM Info 192.168.88.1 CHAP authentication succeeded
6/5/2018 11:49 AM Notice 192.168.88.1 CHAP authentication succeeded
6/5/2018 11:49 AM Info 192.168.88.1 No response to 5 echo-requests
6/5/2018 11:49 AM Notice 192.168.88.1 Serial link appears to be disconnected.
6/5/2018 11:49 AM Notice 192.168.88.1 Connection terminated.
6/5/2018 11:49 AM Notice 192.168.88.1 Modem hangup
6/5/2018 11:49 AM Info 192.168.88.1 Exit.
6/5/2018 11:49 AM Notice 192.168.88.1 Interface ‘modem’ is now down

There are some things with this modem that make it a little more complicated to deal with, but I think that I have got those things sorted. I am using a T-Mobile SIM card that is provisioned for tethering/hotspot use as it is what I am using in my old MiFi with EC-25 card. This SIM works with the MC7455 in Windows as long as the adapter is in MBIM mode, which doesn’t appear to work in the MiFi.

Tethering with this card does not work at all.

Let me know what Else I can do.

Forgot to mention that QMI does not work. I can log an attempt if you like.

I want to sincerely thank you for this post. Between trying my modem (340u) with Rooter and your point on qcserial, after days of work, I was able to get mine to function properly. I hope you find resolve to your issue.

Edit: QMI works too. I had to install luci-proto-qmi and kmod-usb-net-cdc-ether. I then built the connection in the gl inet interface and rebooted. Then I removed creds and set auth to none and made sure it was set to boot on startup in luci. Finally I rebooted and it was brought up automatically. QMI is definitely ideal so I’m glad I got that working too.

Can you clarify how you didi this?

In LUCI on the interface. When you install those packages it changes from WWAN to QMI Cellular too. I would have built the interface in LUCI too but your software doesn’t allow it.

Major update:

TL;DR: SIM card reader seems to be defective in my new MiFi 2.5
Edit: I am an idiot. The SIM card was inserted incorrectly.

Details:
I have two MiFi routers:

  • MiFi 2.2/EC25-A card - year old
  • MiFi 2.5/MC7455 card - brand new

The following packages needed to be installed to get all the drivers for the MC7455:

  • kmod-usb-serial-qualcomm
  • kmod-usb-net-qmi-wwan

I got the MiFi 2.5 working with an external USB device using /dev/ttyUSB2. This made me wonder if there was a problem with the SIM card, so I swapped that out, but it did not help. The problem is that the connect proceeds to the end, but then an error “No response to 5 echo-requests” is seen.

I put the EC25 in the MiFi 2.5 and it stopped working with the same error. When I placed the MC7455 in the MiFi 2.2, it connected immediately. I am pretty sure that the SIM card cannot be read in the new MiFi 2.5.

The remaining problems are:

  • MiFi 2.2 w/ MC7455 will drop the connection soon after being established.
  • QMI does not work in either router. I have seen references to the kernel needing to be 4.5 or higher for QMI to work with the MC7455 due to raw-ip mode.

@alzhao What do you think?

Update 2:

  • Dropped connection:
    This dropped connection problem persists. I cannot tell from the log files what is causing it. It seems like when the FW config is reloaded after the 3g-modem is up.

  • QMI:
    This does not seem to work at all on this build of openwrt. I have flashed the AR150 build of ROOter on this MiFi for testing and surprise! It works perfectly in QMI mode. They seem to have a really nice feature set for managing modems as well. It turns out that QMI does not seem to work with this modem in ROOter either, but MBIM does. Unfortunately, the driver for MBIM mode does not seem to be available on the MiFi.

  • Using alternative builds of openwrt:
    The MC7455 in MBIM mode with the AR150 build of ROOter on this MiFi and it works great except that the LEDs don’t work. Any idea how to fix that?

As ROOter is openwrt as well, you can config the LEDs manually. It should be /etc/config/system

I talked to the admins over at the ROOter forums, who graciously built a bin for the MiFi after I was unsuccessful.

So is everything works good now?

We sent samples of MiFi to ROOter team a while ago.

Hi, I tried to connect the mc7455, which is in an usb adapter, to via Mifi usb port.

Modem is in Mbim mode.
I tried with actual Golden Orb for Ar150, but it seems USB port on Mifi is not working at all with AR150 firmware.

Any news of Rooter for Mifi?

https://ofmodemsandmen.com/upload/

About half way down.

Works great!

What did you have to do to get the MC7455 working?

https://ofmodemsandmen.com/upload/gl-mifi-GO2019-01-13.zip

Install that Firmware.

Thanks! Was there a way to get back to the original firmware? Were there any other steps to get the MC7455 working? How do you do band locking on r00ter?

I got a EM7656 to work in a Mifi/GoldenOrb, if that’s still of interest.

Hey, tell me how do you did it ? It would be very interesting for me !