IMX8MM Camera Usage Guide

🚀 Introduction

This guide shows you how to get started using TechNexion camera modules on TechNexion IMX8MM development kits. You must have the background knowledge to modify the kernel configuration, rebuild, and replace the kernel and the device tree source (DTS). This article is based on Yocto 6.0 (Wrynose) 2026Q3 Release with Linux kernel version 6.18.20-2.0.0.

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📸 Supported Camera Modules

TEVS Series

Camera Series	Products
TEVS	TEVS-AR0144 TEVS-AR0145 TEVS-AR0234 TEVS-AR0235 TEVS-AR0246 TEVS-AR0521 TEVS-AR0522 TEVS-AR0544 TEVS-AR0821 TEVS-AR0822 TEVS-AR0830 TEVS-AR1335 TEVS-AR2020

TEVM Series

Camera Series	Products
TEVM	TEVM-AR0144 TEVM-AR0145 TEVM-AR0234 TEVM-AR0235 TEVM-AR0246 TEVM-AR0521 TEVM-AR0522 TEVM-AR0544 TEVM-AR0821 TEVM-AR0822 TEVM-AR0830 TEVM-AR1335 TEVM-AR2020

Example

This article uses the TEVS-AR0521 as an example.

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🧩 Supported Boards

SoM	Board
EDM-G-IMX8M-MINI	WB-EDM-G-IMX8M-MINI
PICO-IMX8M-MINI	PICO-PI-IMX8M-MINI PICO-WIZARD-IMX8M-MINI

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🔧 Hardware Setup Instructions

1. Power Supply Preparation

• Use a DC 5V or 12V power cable to supply power to the board.
• If you are using FPD-Link III SerDes, use a 12V power adapter (minimum 3A) connected through the barrel jack.

2. Debug Console Connection

• Prepare a USB-to-UART cable when connecting to a PC.
• Connect it to the CONSOLE1 connector.

3. Display Output Connection

• Prepare a panel for output display.
• Connect it to the LVDS1 connector on the board.

About display

The provided DTBs include configuration for 10.1-inch and 15.6-inch LVDS display panels, as well as 5-inch MIPI panel.

This output is useful for verifying the camera stream on screen.

4. Camera Interface (CSI) Overview

• The board has one MIPI CSI-2 interface, CSI1.
• It uses a 70-pin board-to-board connector manufactured by Hirose.

About camera

Although the board has two CSI interfaces, only CSI1 is enabled. The IMX8M-MINI only supports one MIPI CSI-2 interface.

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💻 Prepare Yocto demo image for testing TechNexion camera

Use a Yocto demo image that includes the required device tree blobs and camera drivers.

🔽 Downloading the Demo Image

The prebuilt demo image is available on TechNexion's download server.

Download Link

EDM-G-IMX8MM

🔗 Download Prebuilt Image for EDM-G-IMX8MM

PICO-IMX8MM

🔗 Download Prebuilt Image for PICO-IMX8MM

💾 Flashing the Image

Flash the image to e.MMC or an SD card using one of these methods:

Method 1. Using the UUU Tool

🔗 How to Flash with UUU

Boot Mode

Set the board to Serial Download Mode before flashing.

Method 2. Using the U-Boot UMS Command

🔗 Using UMS in U-Boot

U-Boot Requirement

The board must boot a U-Boot version that supports the ums command.

Method 3. For Windows Users

🔗 Using Balena Etcher

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🛠️ Build Yocto

TechNexion supports building a Yocto-based Linux image with the following kernel and branch.

📦 Supported Linux Kernel

Linux Kernel Version	Yocto Branch
6.18.20	tn-imx_6.18.20_2.0.0-stable

📁 Source and Build Instructions

Fetch Yocto Source

EDM-G-IMX8MM

📖 Build Yocto for EDM-G-IMX8MM

PICO-IMX8MM

📖 Build Yocto for PICO-IMX8MM

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📸 Camera Testing Instructions

🌳 Specify Camera DTBO in U-Boot

1. Connect the debug console cable to the carrier board.
2. Power on the board and interrupt boot when Hit any key to stop autoboot: appears.
3. Set the camera overlay:

CSI1 connector

u-boot=> setenv dtoverlay tevs

4. Continue booting.

u-boot=> saveenv
u-boot=> boot

tip

Append the display-panel overlay when you need on-screen camera output.

u-boot=> setenv dtoverlay=tevs sn65dsi84-vl10112880

🎛️ Setup the media controller before camera streaming

Starting from kernel 6.12, the CSI driver supports media-ctl for configuring the pipeline on the i.MX8M Mini platform.

Inspect the media topology:

$ media-ctl -p

Example output:

Media controller API version 6.18.20

Media device information
------------------------
driver          imx7-csi
model           imx-media
serial
bus info        platform:32e20000.csi
hw revision     0x0
driver version  6.18.20

Device topology
- entity 1: csi (2 pads, 2 links, 0 routes)
            type V4L2 subdev subtype Unknown flags 0
            device node name /dev/v4l-subdev0
        pad0: SINK
                [stream:0 fmt:UYVY8_2X8/640x480 field:none colorspace:srgb xfer:srgb ycbcr:601 quantization:lim-range]
                <- "csis-32e30000.mipi-csi":1 [ENABLED,IMMUTABLE]
        pad1: SOURCE
                [stream:0 fmt:UYVY8_2X8/640x480 field:none colorspace:srgb xfer:srgb ycbcr:601 quantization:lim-range]
                -> "csi capture":0 [ENABLED,IMMUTABLE]

- entity 4: csi capture (1 pad, 1 link)
            type Node subtype V4L flags 0
            device node name /dev/video2
        pad0: SINK
                <- "csi":1 [ENABLED,IMMUTABLE]

- entity 10: csis-32e30000.mipi-csi (2 pads, 2 links, 0 routes)
             type V4L2 subdev subtype Unknown flags 0
             device node name /dev/v4l-subdev1
        pad0: SINK,MUST_CONNECT
                [stream:0 fmt:UYVY8_1X16/640x480 field:none colorspace:smpte170m xfer:709 ycbcr:601 quantization:lim-range]
                <- "tevs 1-0048":0 [ENABLED]
        pad1: SOURCE,MUST_CONNECT
                [stream:0 fmt:UYVY8_1X16/640x480 field:none colorspace:smpte170m xfer:709 ycbcr:601 quantization:lim-range]
                -> "csi":0 [ENABLED,IMMUTABLE]

- entity 15: tevs 1-0048 (1 pad, 1 link, 0 routes)
             type V4L2 subdev subtype Sensor flags 0
             device node name /dev/v4l-subdev2
        pad0: SOURCE
                [stream:0 fmt:UYVY8_1X16/1280x800@1/60 field:none colorspace:srgb xfer:srgb ycbcr:601 quantization:full-range
                 crop.bounds:(0,0)/1280x800
                 crop:(0,0)/1280x800]
                -> "csis-32e30000.mipi-csi":0 [ENABLED]

The graph view can make the topology easier to understand.

note

Generate the graph with:

$ media-ctl --print-dot > graph.dot
$ dot -Tpng graph.dot > graph.png
# Install Graphviz if needed:
# sudo apt-get install -y graphviz

Set the resolution and format of every media entity to match the camera output. Check supported formats, resolutions, and frame intervals:

# formats
$ v4l2-ctl -d /dev/v4l-subdev2 --list-subdev-mbus-codes
  ioctl: VIDIOC_SUBDEV_ENUM_MBUS_CODE (pad=0,stream=0)
          0x200f: MEDIA_BUS_FMT_UYVY8_1X16
          0x300a: MEDIA_BUS_FMT_SGRBG10_1X10
          0x3011: MEDIA_BUS_FMT_SGRBG12_1X12

# resolutions
$ v4l2-ctl -d /dev/v4l-subdev2 --list-subdev-framesize code=0x200f
  ioctl: VIDIOC_SUBDEV_ENUM_FRAME_SIZE (pad=0,stream=0)
          Size Range: 640x480 - 640x480
          Size Range: 1280x720 - 1280x720
          Size Range: 1280x960 - 1280x960
          Size Range: 1920x1080 - 1920x1080
          Size Range: 2560x1440 - 2560x1440
          Size Range: 2592x1944 - 2592x1944

# frame interval of resolution
$ v4l2-ctl -d /dev/v4l-subdev2 --list-subdev-frameintervals width=640,height=480,code=0x200f
  ioctl: VIDIOC_SUBDEV_ENUM_FRAME_INTERVAL (pad=0,stream=0)
          Interval: 0.008s (120.000 fps)

$ v4l2-ctl -d /dev/v4l-subdev2 --list-subdev-frameintervals width=1280,height=720,code=0x200f
  ioctl: VIDIOC_SUBDEV_ENUM_FRAME_INTERVAL (pad=0,stream=0)
          Interval: 0.017s (60.000 fps)

$ v4l2-ctl -d /dev/v4l-subdev2 --list-subdev-frameintervals width=1280,height=960,code=0x200f
  ioctl: VIDIOC_SUBDEV_ENUM_FRAME_INTERVAL (pad=0,stream=0)
          Interval: 0.017s (60.000 fps)

$ v4l2-ctl -d /dev/v4l-subdev2 --list-subdev-frameintervals width=1920,height=1080,code=0x200f
  ioctl: VIDIOC_SUBDEV_ENUM_FRAME_INTERVAL (pad=0,stream=0)
          Interval: 0.017s (60.000 fps)

$ v4l2-ctl -d /dev/v4l-subdev2 --list-subdev-frameintervals width=2560,height=1440,code=0x200f
  ioctl: VIDIOC_SUBDEV_ENUM_FRAME_INTERVAL (pad=0,stream=0)
          Interval: 0.031s (32.000 fps)

$ v4l2-ctl -d /dev/v4l-subdev2 --list-subdev-frameintervals width=2592,height=1944,code=0x200f
  ioctl: VIDIOC_SUBDEV_ENUM_FRAME_INTERVAL (pad=0,stream=0)
          Interval: 0.042s (24.000 fps)

Set the resolution to 1280×720, for example:

Command Line

$ media-ctl -V "'csi':0 [fmt:UYVY8_1X16/1280x720 field:none colorspace:srgb xfer:srgb ycbcr:601]"
$ media-ctl -V "'tevs 1-0048':0 [fmt:UYVY8_1X16/1280x720 field:none colorspace:srgb xfer:srgb ycbcr:601]"

Script

#!/bin/bash

# Define the format and resolution as a variable
mdev="/dev/media0"
mediactl="media-ctl -d $mdev"
cam="tevs 1-0048"
csi="csi"
code="UYVY8_1X16"
width="1280"
height="720"
format="fmt:${code}/${width}x${height} field:none"

# Function to run media-ctl commands with error handling
echo "Set media controller..."

$mediactl -V "\"$cam\":0 [$format]"
$mediactl -V "\"$csi\":0/0 [$format]"

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🎥 Start Camera Video Stream via GStreamer

🎬 Launch GStreamer Pipeline

Replace <res_w> and <res_h> with the selected resolution:

$ gst-launch-1.0 v4l2src device=/dev/video2 ! \
  "video/x-raw, format=UYVY, width=<res_w>, height=<res_h>" ! \
  waylandsink sync=false

✅ Check Media Controller

Run media-ctl -p again after setting the resolution and link:

Media controller API version 6.18.20

Media device information
------------------------
driver          imx7-csi
model           imx-media
serial
bus info        platform:32e20000.csi
hw revision     0x0
driver version  6.18.20

Device topology
- entity 1: csi (2 pads, 2 links, 0 routes)
            type V4L2 subdev subtype Unknown flags 0
            device node name /dev/v4l-subdev0
        pad0: SINK
                [stream:0 fmt:UYVY8_1X16/1280x720 field:none colorspace:srgb xfer:srgb ycbcr:601 quantization:lim-range]
                <- "csis-32e30000.mipi-csi":1 [ENABLED,IMMUTABLE]
        pad1: SOURCE
                [stream:0 fmt:UYVY8_1X16/1280x720 field:none colorspace:srgb xfer:srgb ycbcr:601 quantization:lim-range]
                -> "csi capture":0 [ENABLED,IMMUTABLE]

- entity 4: csi capture (1 pad, 1 link)
            type Node subtype V4L flags 0
            device node name /dev/video2
        pad0: SINK
                <- "csi":1 [ENABLED,IMMUTABLE]

- entity 10: csis-32e30000.mipi-csi (2 pads, 2 links, 0 routes)
             type V4L2 subdev subtype Unknown flags 0
             device node name /dev/v4l-subdev1
        pad0: SINK,MUST_CONNECT
                [stream:0 fmt:UYVY8_1X16/1280x720 field:none colorspace:srgb xfer:srgb ycbcr:601 quantization:full-range]
                <- "tevs 1-0048":0 [ENABLED]
        pad1: SOURCE,MUST_CONNECT
                [stream:0 fmt:UYVY8_1X16/1280x720 field:none colorspace:srgb xfer:srgb ycbcr:601 quantization:full-range]
                -> "csi":0 [ENABLED,IMMUTABLE]

- entity 15: tevs 1-0048 (1 pad, 1 link, 0 routes)
             type V4L2 subdev subtype Sensor flags 0
             device node name /dev/v4l-subdev2
        pad0: SOURCE
                [stream:0 fmt:UYVY8_1X16/1280x720@1/60 field:none colorspace:srgb xfer:srgb ycbcr:601 quantization:full-range
                 crop.bounds:(0,0)/1280x800
                 crop:(0,0)/1280x720]
                -> "csis-32e30000.mipi-csi":0 [ENABLED]

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🚨 Troubleshooting

Check DTB Overlay in U-Boot

CSI1 connector

  u-boot=> printenv dtoverlay
    dtoverlay=tevs vxt-vl050-070-8048nt

tip

The vxt-vl050-070-8048nt overlay is for the 5-inch LCD display panel.

Verify Camera Initialization

  $ dmesg -t | grep tevs
    /soc@0/bus@30800000/i2c@30a30000/tevs_mipi@48: Fixed dependency cycle(s) with /soc@0/bus@32c00000/mipi-csi@32e30000
    /soc@0/bus@32c00000/mipi-csi@32e30000: Fixed dependency cycle(s) with /soc@0/bus@30800000/i2c@30a30000/tevs_mipi@48
    /soc@0/bus@30800000/i2c@30a30000/tevs_mipi@48: Fixed dependency cycle(s) with /soc@0/bus@32c00000/mipi-csi@32e30000
    /soc@0/bus@30800000/i2c@30a30000/tevs_mipi@48: Fixed dependency cycle(s) with /soc@0/bus@32c00000/mipi-csi@32e30000
    /soc@0/bus@32c00000/mipi-csi@32e30000: Fixed dependency cycle(s) with /soc@0/bus@30800000/i2c@30a30000/tevs_mipi@48
    /soc@0/bus@30800000/i2c@30a30000/tevs_mipi@48: Fixed dependency cycle(s) with /soc@0/bus@32c00000/mipi-csi@32e30000
    /soc@0/bus@32c00000/mipi-csi@32e30000: Fixed dependency cycle(s) with /soc@0/bus@30800000/i2c@30a30000/tevs_mipi@48
    tevs 1-0048: tevs_probe() device node: tevs_mipi@48
    tevs 1-0048: Version:26.3.0.1
    tevs 1-0048: Product:TEVS-AR0144, HeaderVer:3, MIPI_Rate:800
    tevs 1-0048: Chip ID: 0x0356
    tevs 1-0048: probe success

Confirm Board and Camera DTB

EDM-G-IMX8MM

  $ dmesg -t | grep -i model
    Machine model: TechNexion EDM-G-IMX8MM and WB baseboard
    exc3000 2-002a: Retry 1 get EETI EXC3000 model: -6
    exc3000 2-002a: Retry 2 get EETI EXC3000 model: -6
    exc3000 2-002a: Retry 3 get EETI EXC3000 model: -6

PICO-IMX8MM

  $ dmesg -t | grep -i model
    Machine model: TechNexion PICO-IMX8MM and PI baseboard
    exc3000 2-002a: Retry 1 get EETI EXC3000 model: -6
    exc3000 2-002a: Retry 2 get EETI EXC3000 model: -6
    exc3000 2-002a: Retry 3 get EETI EXC3000 model: -6

Check Available Video Devices

$ v4l2-ctl --list-device

Example output:

imx-capture (platform:32e20000.csi):
        /dev/video2
        /dev/media0

vsi_v4l2dec (platform:vsi_v4l2dec):
        /dev/video1

vsi_v4l2enc (platform:vsi_v4l2enc):
        /dev/video0

Typically, /dev/video2 is the primary camera capture device when using CSI1.