Has anyone tested this combination before? Any idea if the adapter board is compatible with Android on the Pi 4? I know this is a bit of an unusual setup but figured I’d ask before I start pulling my hair out trying to make it work.
Unfortunately, we cannot promise the functionality of the Multi-Camera Adapter Board on the system you mentioned. We haven’t done any compatibility testing or verification against the AOSP15 KonstaKANG build you’re referencing, so there’s no data I can point to either way.
Most of our testing and development for the Multi-Camera Adapter Board on Raspberry Pi has been done with Raspbian/Raspberry Pi OS. The Android AOSP builds for Pi can differ quite a bit in terms of kernel drivers, device tree configuration, and the camera HAL layer — all of which would need to line up for the adapter to work properly.
Are you at a point where you’ve already flashed the build and tried connecting the board, or are you still in the planning phase?
Thanks for the reply. To be clear — I’m not asking for guarantees, I’m asking for verification. I just want to know whether Arducam has ever tested this board with Android on a Pi 4, even informally. Even a “someone tried it and it didn’t work” or “we genuinely don’t know” would be helpful.
I haven’t tried connecting anything yet. I’m still in the planning phase and trying to figure out if this is even worth attempting before I invest time in it. The Android build I mentioned is pretty popular in the Pi community — it’s from KonstaKANG, who’s been maintaining AOSP for Raspberry Pi for years.
Is there any documentation or kernel driver info you can share about what the adapter board expects from the host OS? That might help me figure out if I can bridge the gap myself.
That’s a fair distinction — and I appreciate the clarification. To answer directly: no, we have not tested the Multi-Camera Adapter Board on any Android/AOSP build for the Raspberry Pi 4. I’ve checked internally and there’s no record of informal testing either, so unfortunately I can’t give you a “someone tried it” report in either direction.
The adapter board relies on the standard V4L2 (Video4Linux2) subsystem and I2C for camera control, so in theory if the AOSP kernel you’re using has those enabled and the correct device tree overlays are in place, there’s a path to getting it recognized. The challenge on Android is typically the camera HAL — Raspbian uses the bcm2835-unicam driver and V4L2 directly, but on Android the HAL (hardware abstraction layer) expects a very specific pipeline. The KonstaKANG build may or may not include the necessary kernel drivers for the Pi’s CSI interface to work with multiplexed cameras.
What I’d suggest if you want to explore further: boot the AOSP build, check dmesg and see if the unicam/csi driver is loaded, and look at /dev/video* nodes to see what’s exposed. You’d also want to verify whether the I2C buses are accessible from userspace. That’ll give you a quick sense of whether the kernel side is even in play before worrying about the HAL.
Happy to help interpret whatever you find if you go down that path — but as of now, this is uncharted territory for us.