This is now available as a patch from coderus, see THIS LINK
!You Have to uninstall ofonotwk if you want to install his patch!
You'll get an error at package install if not
You can now access/compile/review source files from there: https://github.com/CODeRUS/ofono/commits/force_fix
Thanks Coderus!
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I finally got it, thanks to jare and nieldk hints.



I have to say that this was a pain in the ..s to get through. It was my first hands on with compile and everything.
But i did it! Yay!

I modified ofono and jolla settings to better suit network mode to my needs.
I think this would interess some other people, so here is a little explaination on how to install it.

But before reading it, you need to know some little things:

Only GSM, WCDMA and LTE technology are used. There are mode to use EVDO and CDMA. But they do not seem much in use so i did not include them. This may cause issue for some of you.

Every settings are provided "as is". You can adjust by yourself, i'll be glad to give all needed information.

If something goes wrong, the phone will still boot and connect to 2G by default.

TechnologyPreference settings:
"any" Radio access technology selection is done automatically, based on reception and availability.
"gsm" Only GSM used for radio access.
"umts" Only UMTS used for radio access.
"lte" Only LTE used for radio access.
"gsmumts" Dual mode, 2G/3G
"umtslte" Dual Mode, 3G/4G

I am not responsible in any way for any problem caused by this tweak. You install it at your own risks!

Here we go!

Ofono Tweak Installation How to:

- Copy ofonotwk3.zip to Downloads
- In terminal as root (devel-su):
- Close everything
- Reboot

Done!

To Remove Ofono Tweak:

- In terminal as root (devel-su):
- Close everything
- Reboot

Done!

Release Notes:

03.02.15
This is now available as a patch from coderus, see THIS LINK
!You Have to uninstall ofonotwk if you want to install his patch!

ofonotwk3 (Vaarainjärvi) 19.12.14
- Update ofono to 1.14+git61-1.16.1

21.10.14
- Coderus was kind enough to fork this and patch the modif there. So from now on you can access/compile/review source file from:
https://github.com/CODeRUS/ofono/commits/force_fix
- Added source of modified files only, full archive is too big to be attached.

ofonotwk2 (Tahkalampi) 15.07.14
- Update ofono to 1.14+git35-1.11.1
- Back to default TechnologyPreference settings name as refered at:http://git.kernel.org/cgit/network/o...ttings-api.txt (don't know why i changed them at first...)
- Update mainpage.qml
- Update "installation/remove how to" following error detection

ofonotwk1 (Saapunki)
original release, ofono1.14+git26.2-1.10.1


-ORIGINAL POST-
Hello,

Does anyone know if it is possible to force 3G only mode in the Jolla phone?

Prefer 3G actually switch a lot to 2G and this is not good for my everyday use.
There is already a thread about this on together, but there are no hint if this is possible via script or config file.

I am a bit lost about mer/nemo/jolla layers so i don't know where to start to search for this.

Any advice would be greatly appreciated.

Best regards.