[Xperia X] [Xperia XA2] [4.5.0.19] GPS: Lost position in flight mode

REPRODUCIBILITY: 100%
OS VERSION: 4.5.0.19
HARDWARE: Xperia XA2 - Dual SIM h4113, XperiaX f5121
UI LANGUAGE: en_GB, Swedish
REGRESSION: Yes, was fixed in 4.4.0.58 or so

DESCRIPTION:

GPS position is immediately lost and never re-acquired when turning flight mode on.
Edit: Added XperiaX, corrected info on top indicator and Location toggle

PRECONDITIONS:

  1. Have Location and Mobile network on
  2. Have a stable GPS fix

STEPS TO REPRODUCE:

  1. Preconditions met
  2. Turn Flight mode on
  3. Location is lost, top indicator goes away, Location toggle remains on

EXPECTED RESULT:

Location to remain stable once a GPS fix is acquired, regardless of Flight mode state.

ACTUAL RESULT:

Location is lost.

MODIFICATIONS:

OpenRepos, Chum

ADDITIONAL INFORMATION:

Watching via the GPSInfo app is quite telling.

This was previously reported here:

Feel free to re-open that issue and move the new info there (I can no longer edit the old topic).

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And reported here too:https://forum.sailfishos.org/t/flightmode-disables-gps/14754?u=phklrz

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@vige , @pherjung it looks like we have an old, closed report (that could be re-opened) plus two new reports (different hardware, different OS versions) about the same problem.

Can we somehow remove duplicates while preserving information?

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Whether we can and whether we should are different things. Probably our best option is just to close the duplicates with links to the one that is kept open. Well, links both ways would be even better.

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Iā€™m not sure about the definition of Flight Mode; there probably isnā€™t an ā€œofficalā€ one. For me it means cut ALL connectivity. That would include GPS.

I could agree but in that case the location button in the top menu should change status (from on to off) which is not the case presently.

Thereā€™s no official definition from Jolla from what I can find. However, Flight mode does seem to be about mobile network, ConnMan and oFono, as evident from the following:

In addition, as noted in my bug report, this was already fixed once before by Jolla.

In addition, the fact that the Location toggle remains on and a GPS fix can be re-acquired just by toggling it seems consistent with my view that the reported behaviour is unintended.

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For me it means: Turn off all transmitters. This includes mobile network, WLAN, BlueTooth, but not GPS because GPS is only a receiver for the satellite signals and doesnā€™t transmit anything. Self-evident no A-GPS possible, but ā€˜pureā€™ GPS reception + positioning is no problem.

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Sure. Question is just where the bug is then: wrong buttons/notifications, or wrong flightmode functionality.

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My impression is, this is not a bug but Jolla coded it this way. I can tell that it is so since 4 Years.

Yes, GPS emits nothing.
Should stay ON in Flight Mode.
One of the interrests of OSMScout or other offline mapping solutions is to be able to navigate in ā€œspy modeā€ :slight_smile:
But if GPS is downā€¦

The reason is perhaps that GPS and modem are in the same chip (at least in XA2 IIUC). Difficult to power off only one of those?

Tested on Android XA2: GPS works well in Airplane Mode (GpsTest app).

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In my experience, GPS used to remain on in Flight mode, then it broke. This was around the time when the offline MLS packages were introduced. Coincidence or causation? I canā€™t say.

Then it was fixed in 4.4 or so.

Then it broke again. Itā€™s unclear to me in which release this happened, as a full root partition kept me on 4.4.0.58 until I went through a brutal spring cleaning and upgraded straight to 4.5.0.19.

I believe this is pretty much the expectation on other platforms, and it used to be the case on SFOS too.

There can be many reasons to use GPS in Flight mode, like navigating or tracking for extended periods of time. Reducing battery drain from the modem, especially where cellular signal is weak, can be essential. (But this is all off-topic.)

Or one may want to know where (or how far) he is on a flight. GPS reception works well inside a plane.

I guess, not the chip, because itā€™s easy possible to turn on the GPS again while still in flight mode. But (only speculating) maybe some firmware or Sony blob function.

Is there a single command for flight mode from UI / SFOS to Sony blob OR does SFOS switch off all transmitting devices one by one on changing to flight mode?

In case 1 the reason may rely to the Sony blob.
In case 2 it should be possible to tweak SFOS to NOT switch off GPS when going into flight mode.

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As noted several times now, here and in the original report against 4.0.2.21, this behaviour has changed back and forth with SFOS upgrades (over the course of five years).

The blobs donā€™t enter into it, unless they are replaced when upgrading Sailfish OS. Does that happen?