Hi all,
I’m trying to get the Radxa Camera 4K (IMX415) working on a Cubie A7Z (Allwinner A733) and I’m stuck at what looks like the sensor’s I²C control link. Hoping someone from Radxa can point me at the correct A7Z wiring/overlay. I think this is the same underlying problem as issue #11 on the radxa-a733 repo.
Setup
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Cubie A7Z + Radxa Camera 4K (IMX415), ribbon on the on-board MIPI-CSI header
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Tried both
rsdk-t4(Debian 13, kernel 6.6.98-3-aw2511) and the officialrsdk-r6(Debian 11, kernel 5.15.147-21-a733) images -
Powered from a proper 5V/27W USB-C supply
What works — I enable the only IMX415 overlay shipped and reboot:
sudo mv /boot/dtbo/cubie-a7a-radxa-camera-4k-415.dtbo.disabled /boot/dtbo/cubie-a7a-radxa-camera-4k-415.dtbo
sudo u-boot-update && sudo reboot
/dev/video0,1,4,5 + /dev/media0 appear, media-ctl -p shows imx415_mipi → sunxi_mipi.1 → sunxi_csi.1 → … → /dev/video0, and the driver binds on I²C at 3-001a (bus twi@2513000, addr 0x1a).
What fails — the documented capture reaches PLAYING but produces no frames:
gst-launch-1.0 v4l2src device=/dev/video0 en-awisp=1 en-largemode=0 \
! video/x-raw,format=NV12,width=1920,height=1080,framerate=30/1 ! fakesink
twi_sunxi-2513000.twi: TWI BUS error state is 0x20
[imx415_mipi]sensor_detect read value is 0x0
[VIN_DEV_I2C_ERR]imx415_mipi sensor write array error, array_size 138!
Chip-ID read (reg 0x3008) returns 0x0 and every sensor write fails — looks electrical (mis-muxed I²C), not a plain NACK.
Already ruled out: reseated ribbon (both orientations); power (27W supply, axp8191-bldo1 enabled @1.8V); capture method (AW-ISP path is correct, just no frames); image version (R6 ships the identical cubie-a7a-... overlay).
The overlay is cubie-a7a-... with compatible = a7a, a7z, a7s, but I suspect the A7Z routes camera I²C/MIPI/pins differently from the A7A.
Questions: (1) Is there an A7Z-specific camera-4k overlay? (2) Correct I²C bus/address for the A7Z camera connector? (3) Correct MIPI lane + MCLK/reset/pwdn GPIO mapping? (4) Which regulator powers it — bldo1? (5) Can you share the A7Z CSI connector pin mapping/schematic or a verified overlay? Happy to run diagnostics or share full dmesg/media-ctl output. Thanks!