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OE4T / meta-tegra

BSP layer for NVIDIA Jetson platforms, based on L4T
MIT License
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cannot find /dev/v4l2 #294

Closed pixellon closed 4 years ago

pixellon commented 4 years ago

Hi,

I am currently using zeus branch l4t on a jetson tx2. I was able to successfully build core-image-weston. However when i try to run the on board camera capture application i do not see a v4l2 device in /dev/v4l2 folder. I dont know if this is a known issue. I would appreciate any help related to this.

Regards, -Ash.

madisongh commented 4 years ago

I see /dev/v4l on my TX2, but not /dev/v4l2. Do you have /dev/video0? Also check that the Argus daemon is running: systemctl status nvargus-daemon.

Also, I'd recommend using the zeus-l4t-r32.3.1 for the latest L4T BSP content. I've found it to be more reliable, particularly for weston.

pixellon commented 4 years ago

Thanks for your suggestion to use zeus-l4t-r32.3.1 . I can confirm I am using zeus-l4t-r32.3.1 branch, However i do not see '/dev/v4l' and '/dev/video0'. the other thing I am observing is that the default build is using systemV and not systemd. do I have to install systemd ?

madisongh commented 4 years ago

You can use sysvinit instead of systemd if you prefer (although I test more often with systemd than with sysvinit). Definitely check that nvargus-daemon is running (e.g. with ps -elf | grep nvargus-daemon). If it's not, try starting it manually (/etc/init.d/nvargus-daemon restart). Also use lsmod to see if the ov5693 driver has been loaded.

If the driver isn't present at all in your image, try adding kernel-modules (or at least kernel-module-ov5693) to CORE_IMAGE_EXTRA_INSTALL - the default build settings don't include all the kernel modules. If nvargus-daemon isn't present, then add, say, nvgstcapture, or gst-play - something that will pull in the user-land camera support.

pixellon commented 4 years ago

@madisongh many thanks for your suggestion after installing the modules i am now able to see the dev/video and dev/v4l2.

madisongh commented 4 years ago

I could make it a bit more automatic... I noticed that for the machine config for the TX1, I have a reference to the kernel module for the camera. I should probably do the same for the TX2.

pixellon commented 4 years ago

I will save you the trouble. I have create a PR including the kernel-module-ov5693 for the TX2 machine configuration.

madisongh commented 4 years ago

Thanks!

cg3dland commented 3 years ago

I am working on dunfell-l4t-r32.4.3 on Jetson Nano now, I build the core-image-sato successfully, but I could not find '/dev/v4l' and '/dev/video0' even if the line 'CORE_IMAGE_EXTRA_INSTALL += " kernel-modules"' is added in local.conf, the nvargus-daemon runs on my Nano.

Anything do I miss?

pixellon commented 3 years ago

kernel-module-ov5693 was missing in my case. Please check if you have this module installed.

cg3dland commented 3 years ago

Any command to do this check? I run command 'lsmod', but no ov5693 driver is listed.

pixellon commented 3 years ago

In your machine/jetson-nano.conf check if you have

MACHINE_EXTRA_RRECOMMENDS += "kernel-module-ov5693"

I had to include the above rebuild the image reflash and everything worked fine. I am not sure if the sensor module on tx2 is the same as the one on nano though.

madisongh commented 3 years ago

@cg3dland Do you have a camera attached to your Nano? You won't see /dev/video0 show up unless you have a camera attached, with a driver for it loaded, and with appropriate device tree entries (at least for MIPI-CSI cameras). If you haven't already, you should consult the L4T documentation on camera development to get started.

cg3dland commented 3 years ago

@pixellon @madisongh thank you very much! the problem is resolved after I attahed a new USB camera to Nano instead of my old camera, it seem there is something mismatch with my old camera.

A bit confusion, with the new USB camera attached, the devices '/dev/v4l' and '/dev/video0' could be found if the core-image-base built with the line 'CORE_IMAGE_EXTRA_INSTALL += " kernel-modules"' in local.conf, but the devices '/dev/v4l' and '/dev/video0' could NOT be found if the core-image-base built with the line 'CORE_IMAGE_EXTRA_INSTALL += " kernel-module-ov5693"' in local.conf.

pixellon commented 3 years ago

Kernel module kernel-module-ov5693 is specific to the omnivision sensor that comes as a part of jetson tx2. Usb camera modules seems to me are built as a part or general kernel modules kernel-modules. Both are different kernel-module-ov5693 is for the MIPI csi sensor.