Virtual channel support for camera ov5640

Hi all,

Can anyone please let me know, whether it is possible to achieve two camera input streams(640×480) via single CSI through virtual channels(custom hardware)? If yes, please let me know any suggestions?

Thanks,
Pradeep

Hi @pradeep. The answer is yes and no. Yes - The hardware is fully compliant with the MIPI-CSI specification and can support multiple cameras in the virtual channels. Fully tested in simulations.
No - we never had a camera module that could output multiple images on the virtual channels, hence the physical hardware and the software has not been demonstrated as working.

If you really want to get this running I suspect that you will need to provide hardware to Linaro so they can help you develop and test your software.

Full disclosure. I am no longer an employee of Qualcomm, any opinions I have presented do not reflect the opinions of Qualcomm.

Thanks @ljking. Without physical hardware, isn’t it possible to test with test pattern generator yavta ?

Thanks,
Pradeep

Yavata doesn’t generate MIPI-CSI signals that can be wired to the MIPI-CSI inputs on the APQ8016 chip on the 410c board.

@ljking I would like to use two virtual channels on MIPI CSI2. I looked at the kernel code - linux 5.13 and it calls out vc=0 in some places in the camss driver. Would this need to change? How would I go about piping a specific virtual channel to be handled CSI?

Thanks,
Kim

Hi Kim

Unfortunately I haven’t worked for Qualcomm for 4+ years, and I haven’t looked at the Dragonboard on nearly as long. I am not the right person to ask.

-L-

ok. Thanks for responding.

@Loic would you know if I could use a two virtual channels on MIPI CSI2 and what changes I need to make in linux kernel/device tree?