# TK1-SOM AR0330 Camera Setup Guide

## Hardware Information

- The TK1-SOM supports dual CSI-2 ports
- AR0330 sensor: 3MP, 1/3" CMOS
- Camera connects through CSI interface and I2C for control

## System Requirements

- TK1-SOM running L4T (Linux for Tegra) R21.3
- Kernel Version: 3.10.40
- AR0330 driver built into kernel (CONFIG_VIDEO_AR0330=y)

## AR0330 Camera Module Conflict Resolution

The AR0330 camera on TK1-SOM has a known issue with module conflicts. The `nvhost_vi` and `tegra_camera` modules both try to register the VI driver, causing initialization failures.

### Manual Fix

To manually fix the issue:

1. Check if the `nvhost_vi` module is loaded:
   ```bash
   lsmod | grep -i vi
   ```

2. Unload `nvhost_vi` and load `tegra_camera`:
   ```bash
   sudo rmmod nvhost_vi
   sudo modprobe tegra_camera
   ```

3. Verify that the camera modules are now loaded correctly:
   ```bash
   lsmod | grep -E "video|tegra|camera"
   ```
   
   Expected output:
   ```
   tegra_camera           20484  0
   soc_camera_platform     2106  1
   videobuf2_dma_contig     8796  1 tegra_camera
   ```

4. Check if the video device node has been created:
   ```bash
   ls -l /dev/video*
   ```

### Automatic Fix (Recommended)

For a permanent solution that works across reboots, create an init script:

1. Create the init script:
   ```bash
   sudo tee /etc/init.d/camera-module-fix << EOF
   #!/bin/sh
   ### BEGIN INIT INFO
   # Provides:          camera-module-fix
   # Required-Start:    \$local_fs \$remote_fs
   # Required-Stop:     \$local_fs \$remote_fs
   # Default-Start:     2 3 4 5
   # Default-Stop:      0 1 6
   # Short-Description: Fix camera module loading
   ### END INIT INFO
   
   case "\$1" in
     start)
       echo "Unloading nvhost_vi module..."
       rmmod nvhost_vi || true
       echo "Loading tegra_camera module..."
       modprobe tegra_camera || true
       ;;
     stop)
       ;;
     *)
       echo "Usage: /etc/init.d/camera-module-fix {start|stop}"
       exit 1
       ;;
   esac
   
   exit 0
   EOF
   ```

2. Make the script executable and enable it to run at boot time:
   ```bash
   sudo chmod +x /etc/init.d/camera-module-fix
   sudo update-rc.d camera-module-fix defaults
   ```

3. Run the script manually to apply changes immediately:
   ```bash
   sudo /etc/init.d/camera-module-fix start
   ```

## Testing the Camera

1. Verify the camera is working by checking its properties:
   ```bash
   v4l2-ctl --all --device /dev/video0
   ```

2. Test camera stream with GStreamer:
   ```bash
   gst-launch-1.0 nvcamerasrc ! 'video/x-raw(memory:NVMM),width=1280,height=720,format=NV12,framerate=30/1' ! nvvidconv ! nvoverlaysink
   ```

## Troubleshooting

If the camera is still not detected:

1. Check physical connections to CSI port
2. Verify I2C detection (AR0330 should be on bus 2 at address 0x10 or 0x18):
   ```bash
   for i in {0..5}; do echo "=== i2c-$i ==="; sudo i2cdetect -y $i; done
   ```

3. Check kernel logs for errors:
   ```bash
   dmesg | grep -i "camera\|ar0330\|tegra\|vi"
   ```

## Additional Resources

- TK1-SOM Reference Guide
- AR0330 Datasheet
- L4T Documentation