Troubleshooting phonecall problem on Librem 5 Birch

Trying to figure out why phonecalls don’t seem to work on my Librem 5 Birch (reflashed with the latest image a couple of days ago and having installed all updates after that). Text messaging works fine, which I suppose indicates that the SIM card is okay.

When trying to place a phone call, it shows “Calling…” for about 30 seconds, but no call is made. I think this “Calling…” state that I get is what it looks like while trying to establish the call, then I expect it would look differently once the call has started (like showing elapsed time during the call) but that never happens, it just shows “Calling…” for 30 seconds and then stops.

There is no error message as far as I can see. Could there be an error message or other useful info in a log file somewhere, if so, where to look?

Is there a way to make a phonecall from the command-line, that could show where it gets stuck, or some debugging options I could turn on?

Other ideas for how to troubleshoot phone call problems?

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which modem did you choose?

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I have a Chestnut and I don’t usually keep a SIM card in it. But I put one in to test phone calls again. I think I saw the same behavior as you are reporting the first time I attempted a call but after that it seems to be working. It still takes a while (~20 seconds) between initiating the call and the call actually going through.

I connected to the phone over ssh and ran “sudo journalctl -u ModemManager -f” which follows the modem manager logs in real time. I then tried the call again and saw some log messages. I know almost nothing about ModemManager but if you post the logs from during a call maybe someone who does know about ModemManager may be able to help.

For reference, this is what I see in the logs during a successful (though unanswered) call:

Aug 09 11:26:03 librem5 ModemManager[567]: <info>  [modem0/call0] user request to start call
Aug 09 11:26:03 librem5 ModemManager[567]: <info>  [modem0/call0] call state changed: unknown -> dialing (outgoing-started)
Aug 09 11:26:03 librem5 ModemManager[567]: <info>  [modem0/call0] call is started
Aug 09 11:26:05 librem5 ModemManager[567]: <warn>  [modem0] unexpected incoming call to number 'n/a' reported in call list: state active
Aug 09 11:26:05 librem5 ModemManager[567]: <warn>  [modem0] unexpected incoming call to number 'n/a' reported in call list: state active
Aug 09 11:26:07 librem5 ModemManager[567]: <warn>  [modem0] unexpected incoming call to number 'n/a' reported in call list: state active
Aug 09 11:26:07 librem5 ModemManager[567]: <warn>  [modem0] unexpected incoming call to number 'n/a' reported in call list: state active
Aug 09 11:26:09 librem5 ModemManager[567]: <warn>  [modem0] unexpected incoming call to number 'n/a' reported in call list: state active
Aug 09 11:26:09 librem5 ModemManager[567]: <warn>  [modem0] unexpected incoming call to number 'n/a' reported in call list: state active
Aug 09 11:26:11 librem5 ModemManager[567]: <warn>  [modem0] unexpected incoming call to number 'n/a' reported in call list: state active
Aug 09 11:26:11 librem5 ModemManager[567]: <warn>  [modem0] unexpected incoming call to number 'n/a' reported in call list: state active
Aug 09 11:26:13 librem5 ModemManager[567]: <info>  [modem0/call0] call state changed: dialing -> ringing-out (unknown)
Aug 09 11:26:13 librem5 ModemManager[567]: <warn>  [modem0] unexpected incoming call to number 'n/a' reported in call list: state active
Aug 09 11:26:13 librem5 ModemManager[567]: <warn>  [modem0] unexpected incoming call to number 'n/a' reported in call list: state active
Aug 09 11:26:15 librem5 ModemManager[567]: <warn>  [modem0] unexpected incoming call to number 'n/a' reported in call list: state active
Aug 09 11:26:15 librem5 ModemManager[567]: <warn>  [modem0] unexpected incoming call to number 'n/a' reported in call list: state active
Aug 09 11:26:17 librem5 ModemManager[567]: <warn>  [modem0] unexpected incoming call to number 'n/a' reported in call list: state active
Aug 09 11:26:17 librem5 ModemManager[567]: <warn>  [modem0] unexpected incoming call to number 'n/a' reported in call list: state active
Aug 09 11:26:18 librem5 ModemManager[567]: <info>  [modem0/call0] user request to hangup call
Aug 09 11:26:18 librem5 ModemManager[567]: <warn>  [modem0/call0] couldn't hangup single call with call id '3': Unknown error
Aug 09 11:26:19 librem5 ModemManager[567]: <info>  [modem0/call0] call state changed: ringing-out -> terminated (terminated)

I don’t know what the “unexpected incoming call” lines are about.

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Looks like it didn’t hang up so much as crash gracefully, unless “call id 3” is something else.

I did not choose it myself, bought the phone second-hand, but it seems to be a BroadMobi modem based on this line of output from sudo journalctl -u ModemManager :

Aug 10 01:29:39 pureos ModemManager[496]: <info>  [device /sys/devices/platform/soc@0/38200000.usb/xhci-hcd.4.auto/usb1/1-1/1-1.2] creating modem with plugin 'broadmobi' and '6' ports

There is also a “bm818” device at /sys/devices/platform/sound-wwan/30030000.sai-bm818 so probably BroadMobi BM818.

Thanks!

I tried that and got the following:

Aug 10 02:36:13 pureos ModemManager[496]: <info>  [modem0/call0] user request to start call
Aug 10 02:36:13 pureos ModemManager[496]: <info>  [modem0/call0] call state changed: unknown -> dialing (outgoing-started)
Aug 10 02:36:14 pureos ModemManager[496]: <info>  [modem0/call0] call is started
Aug 10 02:36:16 pureos ModemManager[496]: <warn>  [modem0] unexpected incoming call to number 'n/a' reported in call list: state active
Aug 10 02:36:18 pureos ModemManager[496]: <warn>  [modem0] unexpected incoming call to number 'n/a' reported in call list: state active
[removed 12 similar "unexpected incoming call" lines here]
Aug 10 02:36:44 pureos ModemManager[496]: <warn>  [modem0] unexpected incoming call to number 'n/a' reported in call list: state active
Aug 10 02:36:46 pureos ModemManager[496]: <warn>  [modem0] unexpected incoming call to number 'n/a' reported in call list: state active
Aug 10 02:36:47 pureos ModemManager[496]: <info>  [modem0/call0] call state changed: dialing -> terminated (unknown)

So I get the “call state changed: unknown -> dialing” and “call is started” like you, but then in my case it never gets to “call state changed: dialing -> ringing-out”, for me it just stays in the “dialing” state until it apparently gives up.

Thats certainly an issue you need to research before you buy . the broadmobi bm818A1 is the us variant modem . if its not the A1 designation its not a north american designation and the phone could be trying to make calls on bands that dont exist in your market. Not saying thats YOUR problem but when buying second hand this is atleast one issue you should be aware of.

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Yes, maybe that is what’s happening. I wonder if there is a way to find out, to see which band(s) it is trying to use.

But if it’s using wrong bands, in that case, isn’t it strange that text messaging is working? And it does show “4G” with a few bars up in the left corner of the screen, supposedly indicating that it can communicate with some cell tower.

True. For some reason I didn’t think about the modem issue when buying it. But if it turns out I can’t get calls to work because of the modem type then that’s no disaster, there’s still a million other fun things I can play around with. It’s just a shame because calls tends to be the first question that comes up when showing it to someone. People keep obsessing about phonecalls when I just want to show them the terminal and that the phone is running GNU/Linux! :smiley:

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Doing a little research on the text and call issue to see if texts and calls use the same bands . I seem to remember hearing Some companies use VOLTE and texts use 3g while voice calls use 4g . Are you in the US and perhaps a rural area ? Dont be specific in your location a general geographic description will be fine

Also it could perhaps be an APN issue. I dont know how carrier APNs are set up on these things . Sometimes you need to program certain carrier settings into the phone so it knows how to connect with a network . I use to have that problem on earlier unlocked android phones or custom roms Id flashed . Sometimes the roms came with blank APNs youd have to fill out .

Maybe someone @puri.sm can comment on whether or not APNs are a thing and if they need to be programmed for different carriers ?

This will be my first linux phone when I get mine so Im kinda flying blind on how the network sector operates myself . Kinda feels like 2006 HTC mytouch xD

Sweden :sweden:

yea id definitely take the phone down and see what 2 letters follow the BM818-XX <— these two letters and report back . If they say A1 you have a north american variant modem and thats a problem .

It says “BM818-A1”.

You are in for a world of pain, depending on a) your country (which you already told us) b) the specific mobile network operator within your country that you use c) the specific location within your country d) the choices that your carrier makes.

I don’t know whether it’s an option to order the European variant from Purism (or from somewhere else) and carefully replace the modem yourself.

The frequency differences are mentioned here: https://www.broadmobi.com/en/module_show.php?id=18

In some cases the wrong module would work anyway but it is risky (from the point of view of not working), particularly if you travel around within your country.

That very well may be your issue , you need to lookup what bands your carrier uses , then what bands your local towers broadcast /.

weird i was looking sweden up on cellmapper.net and i can find any tower infos

Something else to consider is the fact that phone calls will downgrade to 3G/2G as we currently haven’t enabled VoLTE on that modem. If you are in an area with poor 3G/2G connectivity but fine LTE connectivity, you could certainly be in a situation where SMS works but calls don’t. I’d suggest going into Settings and forcing the cellular modem to use 3G only or 2G only and see what kind of signal you get and whether you can make a call at that point.

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Will Purism sell us just a modem to us if we need to use the phone in a different geography than the one our current modem was made to support? If so, how much would the modem be and how soon will it be on the market?

Also, if data works you could still make VOIP calls maybe.

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You mean cellmapper.net ?

Thanks, I’ll try that!

yes sorry . I mistaked :smile: