# Troubleshoot camera

If the camera app doesn’t work, check the following:

1. Check the camera module connection and DIP switch settings. See [Getting started](https://docs.qualcomm.com/doc/80-70022-17/topic/stream-cameras_RB4_VERSION.html#getting-started).
2. Restart the cam-server:

# systemctl restart cam-server
        
        or:
        
        # pkill cam-server
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3. Run a single stream video recording use case:

# mount -o rw,remount /usr
        
        gst-launch-1.0 -e qtiqmmfsrc name=camsrc camera=0 ! \
        video/x-raw,format=NV12,width=1280,height=720,framerate=30/1,\
        interlace-mode=progressive,colorimetry=bt601 ! v4l2h264enc \
        capture-io-mode=4 output-io-mode=5 extra-controls="controls,video_bitrate=6000000,\
        video_bitrate_mode=0;" ! h264parse ! mp4mux ! filesink location=/opt/mux_avc.mp4
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4. Check the sensor probe.

    1. Collect logs using following command:

# journalctl -f > /opt/log.txt
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    2. Search for “probe success” in the log. Probe success means the camera module is powered up and responding to I2C control. If there is no ‘probe success’ log for a particular sensor, the flex cable connection or camera module may be the problem.

        The following log indicates one IMX577 (0x34), one OV9282 (0xc0), and two GMSL deserializer (0x90) are probed:

CAM_INFO: CAM-SENSOR:cam_sensor_driver_cmd: 938: Probe success,slot:0,slave_addr: 0x34,sensor_id:0x577, is always on:0
            CAM_INFO: CAM-SENSOR:cam_sensor_driver_cmd: 938: Probe success,slot:1,slave_addr: 0xc0,sensor_id:0x9281, is always on:0
            CAM_INFO: CAM-SENSOR:cam_sensor_driver_cmd: 938: Probe success,slot:4,slave_addr: 0x90,sensor_id:0x94, is always on:0
            CAM_INFO: CAM-SENSOR:cam_sensor_driver_cmd: 938: Probe success,slot:5,slave_addr: 0x90,sensor_id:0x94, is always on:0
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5. Check the camera sensor driver command.

    Collect logs and search for `cam_sensor_driver_cmd`. `CAM_START_DEV Success` indicates camera sensor streaming starts. `CAM_STOP_DEV Success` indicates camera sensor streaming stops. For example:

CAM_INFO: CAM-SENSOR:cam_sensor_driver_cmd: 1017: CAM_ACQUIRE_DEV Success, sensor_id: 0x577,sensor_slave_addr:0x34
        CAM_INFO: CAM-SENSOR:cam_sensor_driver_cmd: 1128: CAM_START_DEV Success, sensor_id: 0x577,sensor_slave_addr:0x34
        CAM_INFO: CAM-SENSOR:cam_sensor_driver_cmd: 1156: CAM_STOP_DEV Success, sensor_id:0x577,sensor_slave_addr:0x34
        CAM_INFO: CAM-SENSOR:cam_sensor_driver_cmd: 1070: CAM_RELEASE_DEV Success, sensor_id: 0x577,sensor_slave_addr:0x34
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6. Check sensor streaming.

    1. Enable CSID SOF/EOF IRQ logs:

# mount -o rw,remount /usr
            # mount -t debugfs none /sys/kernel/debug/
            # echo 3 >/sys/kernel/debug/camera/ife/ife_csid_debug
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    2. Start capturing dmesg logs:

#dmesg -w > /opt/dmesg.txt
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    3. Start the camera using the GST command.
    4. The captured logs can help provide the details about the SOF and EOF and indicate which sensor is streaming. The following is an example log:

<idle>-0       [000] d.h1. 19287.546764: cam_log_debug:
            CAM_DBG: CAM-ISP: cam_ife_csid_irq: 4996: irq_status_ipp = 0x1110 cam-server-25604     [000] dNH.. 19287.561705: cam_log_debug:
            CAM_DBG: CAM-ISP: cam_ife_csid_irq: 4996: irq_status_ipp = 0xee8
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Last Published: Oct 15, 2025

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