# 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/80-70018-17/topic/stream-cameras.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:

Jun 20 02:12:42 qcm6490 kernel: CAM_INFO: CAM-SENSOR:
            cam_sensor_driver_cmd: 938: Probe success,slot:0,slave_addr:0x34,sensor_id:0x577, is always on: 0 Jun 20 02:12:42 qcm6490 kernel: CAM_INFO: CAM-SENSOR:
            cam_sensor_driver_cmd: 938: Probe success,slot:1,slave_addr:0xc0,sensor_id:0x9281, is always on: 0 Jun 20 02:12:43 qcm6490 kernel: CAM_INFO: CAM-SENSOR:
            cam_sensor_driver_cmd: 938: Probe success,slot:4,slave_addr:0x90,sensor_id:0x94, is always on: 0 Jun 20 02:12:43 qcm6490 kernel: 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:

Jun 20 02:12:50 qcm6490 kernel: CAM_INFO: CAM-SENSOR:
        cam_sensor_driver_cmd: 1017: CAM_ACQUIRE_DEV Success, sensor_id:0x577,sensor_slave_addr:0x34, is always on: 0 Jun 20 02:12:50 qcm6490 kernel: CAM_INFO: CAM-SENSOR:
        cam_sensor_driver_cmd: 1128: CAM_START_DEV Success, sensor_id:0x577,sensor_slave_addr:0x34
        Jun 20 02:12:53 qcm6490 kernel: CAM_INFO: CAM-SENSOR:
        cam_sensor_driver_cmd: 1156: CAM_STOP_DEV Success,
        sensor_id:0x577,sensor_slave_addr:0x34
        Jun 20 02:12:53 qcm6490 kernel: 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 0x8 > /sys/module/camera/parameters/debug_mdl
            # echo 3 >/sys/kernel/debug/camera_ife/ife_csid_debug
            # echo 1 > /sys/kernel/tracing/tracing_on
            # echo 1 > /sys/kernel/tracing/events/camera/cam_log_debug/enable # echo 2 > /sys/module/camera/parameters/debug_type
            # cat /sys/kernel/tracing/trace_pipe > trace.txt
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    2. The captured logs can help provide the details about the SOF and EOF. Search for `irq_status_ipp` in the log (`trace.txt`). BIT12(0x1000) denotes an SOF packet and BIT9(0x200) denotes an EOF packet. The log should resemble the following:

<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: Apr 10, 2025

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