RFCOMM TTY support non available

Pulsar33

As seen a long time ago with E5 HD Canonical last version, but tested today with up to date E5 HD UBports OTA-18:
phablet@ubuntu-phablet ~ $ hcitool scan
Scanning ...
[GPS ADDRESS] BT-GPS-3197E9
phablet@ubuntu-phablet ~ $ sudo rfcomm bind 0 [GPS ADDRESS] 1
RFCOMM TTY support not available
phablet@ubuntu-phablet ~ $ ls /dev/rf*
/dev/rfkill

Does someone know why "TTY support" is not available ?
Would be glad to connect some hardware through low level TTY protocols ...

Best regards
Pulsar33

flohack

@pulsar33 said in RFCOMM TTY support non available:

RFCOMM TTY support not available

Well that means probably that the kernel option BT_RFCOMM_TTY is not set. Unfortunately we cannot change this, the build trees for the legacy BQ and Meizu devices are not public and therefore we cannot rebuild those device.

Pulsar33

@flohack thank you for your reply but I'm not sure to understand one point. You speak about "the build trees for the legacy BQ and Meizu". As said in my signature, I've now 2 BQ E5, one with last canonical version (is this what you call "legacy" ?) and one with your UBports OTA-18. Do you mean that there's parts of the kernel that you can't modify ? If this is unfortunately true, this can imply huge limits
On Raspberry Pi4, developers have been able to modify on request a kernel option concerning apparmor and even if it was long to be accepted, it was done. No such possibility exists for UBports or only for BQ and Meizu ?
BR
Pulsar33

Keneda

@pulsar33
Legacy is for devices sold with Ubuntu Touch preinstalled in the Canonical era, wich are Meizu and BQ.

But you can have a "legacy" device with a UBports uTouch version on it, like you, and i, have

flohack

@pulsar33 we combine the final code that runs in your device out of a common part, our so-called "rootfs" and the Android adaption parts, that is: Kernel, device and vendor tree. Latter were not released by BR (and in turn by Mediatek) so that we could rebuild the kernel, yes, your assumption is true.
Thats also the reason why it will be very hard to continue to support this hardware in the future.

Pulsar33

@flohack @Keneda thank you once more to you
I was not prepared to be informed that this hardware has so much limitations for the future. My current experience with OTA-18 is good after some days of trials, including Libertine which I didn't know before. I hope you will maintain this hardware as long as possible
BR
Pulsar33

flohack

@pulsar33 Well Android phones are not made like PCs, you are not meant to decide what you can do with it but the vendor does for you

BR and yes we will give our best

Keneda

@flohack
Well, even on PC it depends on hardware vendors to provide drivers, specially opensource ones are a thing by themselves like you must know, and now for OS like windows 11, microsoft decides on what hardware you can, or not, install it...

They really don't like us to be libre users

For phones, the only long term solution for me is devices like Pinephone, and i think it will be my phone when my MX4 will be deprecated, hopefully uTouch will 100% support it by then...

nero355

@flohack said in RFCOMM TTY support non available:

@pulsar33 we combine the final code that runs in your device out of a common part, our so-called "rootfs" and the Android adaption parts, that is: Kernel, device and vendor tree. Latter were not released by BR (and in turn by Mediatek) so that we could rebuild the kernel, yes, your assumption is true.
Thats also the reason why it will be very hard to continue to support this hardware in the future.

Can you give me a link with a explanation of the way these things are related to one another ?

I have recently bought a Xiaomi 9T which has some "Not daily useable builds" for :

Jolla Sailfish
Ubuntu Touch

Via Hybris and GSI ports somehow but I can't get either one of them to run so I want to know what the heck I am doing wrong...

Flashing the Stock ROM (any version) and TWRP afterwards is no issue at all