Fingerprint sensor cannot wake up device from sleep

[JamiKettunen]

Is this a new report?

Yes

Device model

Volla Phone 22 (2022)

OS version

20.04 (r35)

Describe the bug

Tapping your finger on the fingerprint sensor should wake the device up similar to pressing the power button, after which you can easily unlock it.

Steps to reproduce the bug

1. Setup fingerprint ID unlocking
2. Press power button to turn the screen on
3. Put finger on fingerprint sensor
4. Nothing happens

Expected behaviour

Device should wake up from sleep and the display turn on.

Additional context

FW93XX_FDT_UP_DETECT is visible on Android dmesg when this functionality works, but it seems on Ubuntu Touch the trustzone fingerprint sensor firmware just enters a FW93XX_Sleep mode instead where nothing is transmitted back to the kernel in, needs further confirmation though.