Display overlay not being loaded

[cinchent]

Noob here. I've just installed the "official" FT5406 7" display hardware onto my RPI 3, and it works swimmingly as a display. It doesn't work at all as a touchscreen. No touch events get registered.

Suspecting that this is a DT problem for the display driver/overlay/whatever, I did a 'vcdbg log msg' and noticed that indeed, there are failures to load the various rpi-* overlays for the display. Adding 'dtdebug=1' to the 'config.txt' file revealed:
dtdebug: Failed to open overlay file 'overlays/rpi-ft406.dtb'
and similarly for the other rpi-* (backlight, backlight-overlay, etc.).

These files do not in fact exist: they have .dtbo extensions instead, although all the other DT overlays there have .dtbo extensions as well. Anyway, renaming the rpi-*.dtbo files to rpi-*.dtb had no effect anyway -- the same error messages resulted.

Scouring the web for solutions, I made sure I was fully updated to the very latest and greatest kernel, drivers, and the whole schmear. The 'uname -a' output is:
Linux raspberrypi 4.4.12v7-aufs #1 SMP Fri Jul 10 23:34:12 CEST 2016 armv71 GNU/Linux

Any solutions you know of?

[DirkS]

Scouring the web for solutions, I made sure I was fully updated to the very latest and greatest kernel, drivers, and the whole schmear. The 'uname -a' output is:
Linux raspberrypi 4.4.12v7-aufs #1 SMP Fri Jul 10 23:34:12 CEST 2016 armv71 GNU/Linux

That's not the latest... actually it's not a standard Raspberry Pi kernel.
Looks like a berryboot system to me.

Did you update the system with 'rpi-update'?

[cinchent]

Interesting. Yes, it uses berryboot, but I had assumed that which bootloader to use vs. which kernel were two independent propositions. You seem to be suggesting that berryboot has its own lineage of Raspbian kernels that are forked (or are otherwise distinct) from the standard lineage.

I had originally updated it with 'rpi-update', then did the more typical:
apt-get update
apt-get upgrade
apt-get dist-upgrade
apt-get install raspberrypi-ui-mods
apt-get install raspberrypi-net-mods
which replaced damn near everything, presumably with the most recent version, which sported a Pixel display manager.

I just punted, and loaded the standard Jessie/Pixel image directly from raspberrypi.org, and Bob's my uncle. Everything works fine. Now 'uname -a' shows:
Linux raspberrypi 4.4.34-v7+ #930 SMP Wed Nov 23 15:20:41 GMT 2016 armv71 GNU/Linux

The berryboot option definitely cost me some hours...

Thanks for the help.