OV5647 + gstreamer + H264 errors


To see if this board is viable for further projects, I’m trying to test a H264+RTSP camera stream using an OV5647 (Raspberry Pi’s camera) and gstreamer.

The guides for the DragonBoard 410c’s (since it has the same SoC) are pretty much useful for setting the board up.
For the OS I’m using the Linaro’s Debian Sid and trying the samples mentioned under there: Linaro Releases

Trying to enable camera

For enabling to camera, I’ve found this thead helpful: How to enable dual OV5645 on DB410c
It links to a small tool to update the dtb (dt-update), which I’ve tried. However, after checking the actual device tree of the board itself ( arch/arm64/boot/dts/qcom/apq8016-sbc.dts ), some nodes are different and/or already enabled.
In the end I’m trying with the following overlay:

/ {
        compatible = "qcom,msm8916";

        fragment@1 {
                target-path = "/soc/cci@1b0c000/i2c-bus@0/camera_rear@3b";
                //#address-cells = <1>;
                //#size-cells = <0>;
                __overlay__ {
                        reg = <0x36>;
                        compatible = "ovti,ov5647";
                        status = "okay";

This doesn’t report any errors in dmesg around the part where the “Linux video capture interface v:2.00” comes up, but neither a camera registry log line or “/dev/media0” doesn’t appear either.

Could you please give me hints what to do further?

Gstreamer + RTSP + H264

Until the camera starts working, I am trying to test h264 encoding with gstreamer using videotestsrc as source.

The funny thing is that while a simpler videotestsrc ! v4l2h264enc ! rtph264pay ! udpsink transfer seems to be working, a minimal gsteamer RTSP server (same pipeline minus the udpsink) gives the following error:

0:00:00.719329460 40973 0xffff7c003cc0 WARN                    v4l2 gstv4l2object.c:4432:gst_v4l2_object_probe_caps:<v4l2h264enc0:src> Failed to probe pixel aspect ratio with VIDIOC_CROPCAP: Invalid argument
0:00:00.732949919 40973 0xffff7800c640 WARN          v4l2bufferpool gstv4l2bufferpool.c:814:gst_v4l2_buffer_pool_start:<v4l2h264enc0:pool0:sink> Uncertain or not enough buffers, enabling copy threshold
0:00:00.753565037 40973 0xffff7800c5e0 WARN          v4l2bufferpool gstv4l2bufferpool.c:814:gst_v4l2_buffer_pool_start:<v4l2h264enc0:pool0:src> Uncertain or not enough buffers, enabling copy threshold
0:00:00.776062571 40973 0xffff7800ccc0 WARN          v4l2bufferpool gstv4l2bufferpool.c:1288:gst_v4l2_buffer_pool_dqbuf:<v4l2h264enc0:pool0:src> Driver should never set v4l2_buffer.field to ANY
0:00:00.786890812 40973     0x3cebaa40 WARN               rtspmedia rtsp-media.c:4596:gst_rtsp_media_suspend: media 0xffff7c0531f0 was not prepared

Could you please give me pointers why this could be happening?