Camera stops working after resume from suspend

[jchw]

Hey all. I have a PPP and I am running Mobian Trixie + Phosh. I have GNOME Snapshot installed via Flatpak, and I have PipeWire set up as the system audio daemon.

GNOME Snapshot works quite well right after booting, but after suspending the output in snapshot is blank.

Now, I want to debug this, but I haven't found any leads. I am more than happy to get my hands dirty. I tried searching for this issue on Google a few times, but either Google fails me, or it seems there is not much written about this issue. I can see that PPP camera goes through Pipewire and libcamera, but I don't see any obvious issues from the Pipewire PoV and restarting the Pipewire daemon does not help.

Anyone know what I can do here? Again, happy to get my hands dirty, but I am having a bit of difficulty finding threads to pull on.

[dchang0]

I don't know if this will help you, but many PPP owners running Mobian have had wake from suspend problems, including myself.
I ran into it right away after installing Mobian for the first time a few days ago.

And I happened to solve it (as far as I can tell) by upgrading the Quectel modem's firmware to the latest stock version following the official instructions.
My camera does appear to wake from suspend in Mobian, though I have only been running the new modem firmware for a day now. It might be too soon to call it working.

Anyway, check your Quectel modem firmware version and maybe think about upgrading it if needed. It's not a risk-free process, so be cautious.

[dchang0]

Okay, I just ran into this issue, but only on the back (main) camera. The front camera facing the user does wake from suspend.

To repeat, I am running the latest Mobian with all updates as of today plus the latest stock modem firmware.

Quitting and restarting the Camera app does not wake up the suspended back camera. Logging out and logging back in does not wake up the suspended back camera. Rebooting the phone does (unsurprisingly) wake both cameras.

[DrYak]

Okay, I just ran into this issue, but only on the back (main) camera. The front camera facing the user does wake from suspend.

Had the exact same problem on SailfishOS (I haven't checked recently if it stil happens with latest updates).

Main camera is talking over MIPI CSI to the image processing core (ISP) of the RockChip RK3399.

So last time I used to reset RKISP1 and it brought back the camera:

Code:

echo ff920000.isp1 | tee /sys/bus/platform/drivers/rkisp1/{unbind,bind}

(As root. So either log as root or put "sudo" in front of "tee")

Maybe this helps? (I am not sure. Worked for me, but not for users of different distro. Maybe try restarting Pipewire, after having resert RKISP1 ?)