How to enable 7inch LCD on Pine64

Troubleshooting
21

So either the overlay changed or something in the kernel changed, which the overlay can not handle?!
I found a thread in armbian forum where somebody claims it broke with 6.6.44. Oh wait, this is also you?! :smiley:
https://forum.armbian.com/topic/47670-lost-mipi-dsi-display-after-recent-update/

Can you check

ls /proc/device-tree/overlays/

IMO easiest solution is to downgrade the kernel, bc you had a working system with kernel < 6.6.44
Or investigate more, trying to fix the overlay, which is out of my knowledge.

So check for available kernels, download it and modify dietpiEnv.txt to load the correct

22

Thanks for the suggestions.
That directory doesn’t exist on my system,

# ls /proc/device-tree/
'#address-cells'   aliases     compatible       hdmi-connector     model           opp-table-gpu   pmu             soc          thermal-zones
'#size-cells'      backlight   cpus             interrupt-parent   name            osc24M-clk      psci            sound        timer
 __symbols__       chosen      display-engine   memory             opp-table-cpu   osc32k-clk      serial-number   sound_hdmi   wifi_pwrseq
root@Squeezebox:~# ls /proc/device-tree/overlays
ls: cannot access '/proc/device-tree/overlays': No such file or directory
root@Squeezebox:~# locate overlays

but what I’m going to do is to start with my latest working image, which was Armbian with kernel 5.10.4 and work forwards til it breaks, then try to locate the inage and dtb deb files for the kernel before that and install it to my broken DietPi system to se if it fixes it. Then I can try to diff the device tree and overlays between the last working and first broken versions to see what changed. Unfortunately I don’t

have much time for this any more, so it might take a while.

I didn’t find a source for lagacy kernels for DietPi, but hope to be able to roll forward in Armbian and save the .deb’s

23

Ok, the overlays are probalby in /boot, they’re not mounted to /proc

24

I won’t have access to the machine for the next week, but have identified that the problem started somewhere between kernels 6.1.104, Armbian version 02/02/25 and 6.6.750 03/02/25 (dd/MM/yy).

The kernels were sourced through armbian-config, and there were no versions between them, so I’ll need to dig some more to find out exactly where the problem arose, then maybe do some diffing of the device tree and kernel configs and modules.

For now, freezing the kernel at 6.1.104 evades the issue.

I’ll post more when I get more time

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