Finally I did the trick: working incoming calls in v4

[cam1965]

First I installed a fresh v4 firmware.
Then I mounted the v3 image file ( gemian-cosmocom-kde-plasma.img ).
And  copied  the folder droid-hybris from the the v3 image ( /usr/libexec/droid-hybris ) to the v4.( same place  /usr/libexec )
I did a reboot.
Please, do not upgrade the system for now.
You have to hold ( apt-mark hold )  codi-app and lxc-android.
Now you can upgrade.
Incoming calls and outgoing calls are working pretty well.

Unfortunately messaging-app is still with the same problem : only outgoing messages are working.

But I think it is a light to Adam Boardman to solve these problems.
Good Luck .
CAM1965.

[kmd]

hello,

can you please tell a step wise break up and a little deatiled as completly noob. and no background of linux

[cam1965]

hello,

can you please tell a step wise break up and a little deatiled as completly noob. and no background of linux

Hi .
I really don' t have time to do this. ( at least for now ). Sorry .... 
Maybe in the future. If I have time I will post a more detailed instructions here.
CAM1965

[dnapla]

Just to expand on what Cam wrote above.... (this is not my work!)

This assumes you have installed the latest v4 from http://support.planetcom.co.uk/download/cosmo-customos-installer-v4.zip
Once this is installed and working ok (wifi etc).

Download the following file (15Mb). This contains the droid-hybris folder from v3.
https://github.com/dnapla/droidhybris/blob/main/droid-hybris.zip

Apologies (its a zip... I will look to do a tar sometime)
(sudo apt install unzip)

Use whichever program you like to transfer files to Cosmo (eg Filezilla) via SFTP to home directory. ( ~/ )
(unzip droid-hybris.zip)
Will create a droid-hybris folder containing system and vendor folders. (assuming in ~/droid-hybris)

The files all need to be owned by root ( sudo chown -R root:root droid-hybris )

Then copied to the /usr/libexec folder....
There is an existing droid-hybris folder - containing a lot less files on v4.

(sudo cp -r ~/droid-hybris/ /usr/libexec/ )

Reboot

Then ensure codi-app / lxc-android are not updated
(sudo apt-mark hold codi-app lxc-android)

Other files can be updated as usual
(sudo apt-get update)
(sudo apt-get upgrade)

This worked ok for me to get incoming calls. I have not tested messaging (SMS) at all.
This is hopefully a short term workaround.

Hope this works ok for you guys.

[cam1965]

Just to expand on what Cam wrote above.... (this is not my work!)

This assumes you have installed the latest v4 from http://support.planetcom.co.uk/download/cosmo-customos-installer-v4.zip
Once this is installed and working ok (wifi etc).

Download the following file (15Mb). This contains the droid-hybris folder from v3.
https://github.com/dnapla/droidhybris/blob/main/droid-hybris.zip

Apologies (its a zip... I will look to do a tar sometime)
(sudo apt install unzip)

Use whichever program you like to transfer files to Cosmo (eg Filezilla) via SFTP to home directory. ( ~/ )
(unzip droid-hybris.zip)
Will create a droid-hybris folder containing system and vendor folders. (assuming in ~/droid-hybris)

The files all need to be owned by root ( sudo chown -R root:root droid-hybris )

Then copied to the /usr/libexec folder....
There is an existing droid-hybris folder - containing a lot less files on v4.

(sudo cp -r ~/droid-hybris/ /usr/libexec/ )

Reboot

Then ensure codi-app / lxc-android are not updated
(sudo apt-mark hold codi-app lxc-android)

Other files can be updated as usual
(sudo apt-get update)
(sudo apt-get upgrade)

This worked ok for me to get incoming calls. I have not tested messaging (SMS) at all.
This is hopefully a short term workaround.

Hope this works ok for you guys.

Thank you. This will help kmd.
But  unfortunately  messaging-app is working only for outgoing messages...  yet .
You can test it sending a message to yourself in linux. Go to android and you will see the messages in your message app.
In linux in v3 when you send a message to yoursel the message appears twice .
In v4 only once.
I have tried a lot of libraries but up to now no success.
I also have compiled my own kernel in order to work with an  external webcam that I use in Microsoft Teams (Yes , I found a version on the net ) . and also my isdb-t tuner for watchung digital tv in linux.
When I have time I will test an usb dongle with a sim card and with modem-manager-gui.

[dnapla]

For text messages - you need to get a patched version of the following :-
https://gitlab.com/ubports/community-ports/android9/planet-cosmocom/planet-cosmocom/-/commit/16efbf31cb3d333add831107ba3f65d857572128

This should go in /usr/libexec/droid-hybris/vendor/lib64/libmtk-ril.so
Make sure permissions remain the same

Messages received ok now with this

[cam1965]

For text messages - you need to get a patched version of the following :-
https://gitlab.com/ubports/community-ports/android9/planet-cosmocom/planet-cosmocom/-/commit/16efbf31cb3d333add831107ba3f65d857572128

This should go in /usr/libexec/droid-hybris/vendor/lib64/libmtk-ril.so
Make sure permissions remain the same

Messages received ok now with this

Hi.
Thank you so much !
Now it is working !
Thank you again!

[deprecated]

Then ensure codi-app / lxc-android are not updated
(sudo apt-mark hold codi-app lxc-android)

Sorry for the necro, but support for the Cosmo is very limited... have to get it where I can find it! That said, why is holding back codi-app and lxc-android necessary?

For what it's worth, your post (and the other post further down for incoming SMS) work on my Cosmo using v4. So, thanks for that!