# TK1-SOM CSI Camera Testing Guide

## Hardware Information

- The TK1-SOM supports dual CSI-2 ports
- Default camera sensor: IMX135
- Alternative sensor: AR0330 (3MP, 1/3" CMOS)
- Camera connects through CSI interface and I2C for control

## Prerequisites

1. TK1-SOM running L4T (Linux for Tegra)
2. Camera module properly connected to CSI port
3. Required kernel modules:
   - videobuf2-dma-contig.ko
   - soc_camera_platform.ko
   - nvhost-vi.ko
   - tegra_camera.ko

## Checking Camera Presence

### 1. Hardware Connection Check

- Verify physical connection to CSI port
- Check cable orientation and connection integrity
- Ensure camera power supply is connected

### 2. I2C Detection

```bash
# Check each I2C bus for camera presence
for i in {0..5}; do
    echo "=== i2c-$i ==="
    sudo i2cdetect -y $i
done
```

The IMX135 sensor should appear on one of the I2C buses if properly connected.
For AR0330, check i2c-2 for addresses 0x10 or 0x18.

### 3. Kernel Module Status

```bash
# Check if camera modules are loaded
lsmod | grep -E 'video|tegra|camera'

# Check for video devices
ls -l /dev/video*
```

### 4. System Logs

```bash
# Check kernel messages for camera detection
dmesg | grep -i 'camera\|imx\|tegra\|ar0330'
```

## GStreamer Testing

### 1. Check Available GStreamer Plugins

```bash
# List NVIDIA-specific plugins
gst-inspect-1.0 | grep nv

# Check nvcamerasrc capabilities
gst-inspect-1.0 nvcamerasrc
```

### 2. Test Camera Stream

```bash
# Basic camera test pipeline
gst-launch-1.0 nvcamerasrc ! 'video/x-raw(memory:NVMM),width=1280,height=720,format=NV12,framerate=30/1' ! nvvidconv ! nvoverlaysink
```

## Troubleshooting

### 1. Initial Checks

- Verify camera is connected to CSI #1 port
- Check I2C detection:
  - For IMX135: bus 0 (devices at 0x56 and 0x4c-0x4d)
  - For AR0330: bus 2 (devices at 0x10 or 0x18)
- Verify appropriate driver is loaded in kernel logs
- Check for video device nodes (/dev/video*)

### 2. Module Loading Issues

- Kernel modules must match the running kernel version
- Current kernel: 3.10.40-gc017b03
- Required modules:
  - videobuf2-dma-contig.ko
  - soc_camera_platform.ko
  - nvhost-vi.ko
  - tegra_camera.ko
- Module paths:
  - /lib/modules/3.10.40-gc017b03/kernel/drivers/media/v4l2-core/videobuf2-dma-contig.ko
  - /lib/modules/3.10.40-gc017b03/kernel/drivers/media/platform/soc_camera/soc_camera_platform.ko
  - /lib/modules/3.10.40-gc017b03/kernel/drivers/video/tegra/host/vi/nvhost-vi.ko
  - /lib/modules/3.10.40-gc017b03/kernel/drivers/media/platform/soc_camera/tegra_camera/tegra_camera.ko

### 3. Device Node Issues

- Check if /dev/video- nodes exist
- Verify permissions on video devices
- Check video4linux subsystem: ls -l /sys/class/video4linux/

### 4. GStreamer Testing

- Verify nvcamerasrc plugin is available: gst-inspect-1.0 | grep nv
- Check nvcamerasrc capabilities: gst-inspect-1.0 nvcamerasrc
- Test camera stream with:

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

- Common GStreamer errors:
  - "Can not open camera device": Check physical connection and kernel modules
  - "Pipeline doesn't want to pause": Verify camera power and CSI connection

### 5. Common Problems

- Missing kernel modules
- Mismatched L4T version
- Incorrect I2C address
- CSI lane configuration issues
- Power supply problems
- Camera not properly initialized
- Driver compatibility issues

### 6. AR0330 Specific Issues

- Built into kernel (CONFIG_VIDEO_AR0330=y)
- Uses Platform Camera Layer (PCL) for initialization
- Check device tree configuration:

  ```bash
  # View camera PCL profiles
  cat /proc/device-tree/camera-pcl/profiles/ar0330@2_*/name
  ```

- Common AR0330 problems:
  - I2C communication failures on bus 2
  - PCL initialization failures
  - Video Input (vi) driver registration issues
  - Power sequencing problems
- Hardware checks for AR0330:
  - Verify correct I2C address selection (0x10 or 0x18)
  - Check MIPI/Parallel interface configuration
  - Confirm power supply meets 2.8V analog and 1.8V digital requirements
  - Verify MCLK is properly configured

## System Information

- L4T Version: R21.3
- Kernel Version: 3.10.40
- Architecture: armv7l
- Camera Support:
  - IMX135: Built into kernel (CONFIG_VIDEO_IMX135=y)
  - AR0330: Built into kernel (CONFIG_VIDEO_AR0330=y)
- VI Support: Modular (CONFIG_TEGRA_GRHOST_VI=m)

## Additional Resources

- TK1-SOM Reference Guide
- L4T Documentation
- GStreamer Documentation for NVIDIA plugins
- AR0330 Datasheet for detailed sensor specifications

## AR0330 Camera Troubleshooting Solution

If you're experiencing issues with the AR0330 camera not being detected or initialized properly, follow these steps:

### Module Conflict Resolution

There is a known conflict between the `nvhost_vi` and `tegra_camera` modules. Both try to register the VI driver, causing initialization failures. To resolve this:

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

2. If `nvhost_vi` is loaded but `tegra_camera` is not, 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"
   ```
   
   You should see output similar to:
   ```
   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*
   ```
   
   You should see `/dev/video0` or similar device nodes.

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

### Kernel Version Considerations

- The solution above was tested on kernel version `3.10.40-grinch-21.3.4`
- Make sure you're using the correct module for your kernel version
- Module path: `/lib/modules/3.10.40-grinch-21.3.4/kernel/drivers/media/platform/soc_camera/tegra_camera/tegra_camera.ko`

### Additional Notes

- The AR0330 driver is built into the kernel (`CONFIG_VIDEO_AR0330=y`)
- The PCL profiles for AR0330 are present at `/proc/device-tree/camera-pcl/profiles/ar0330@2_0010` and `/proc/device-tree/camera-pcl/profiles/ar0330@2_0018`
- Even if the camera is not detected on I2C bus 2 (addresses 0x10 or 0x18), this module conflict resolution may still fix the issue