Comment 18 for bug 2061747

Thank you for all of this work. I am not sure that I should be changing the tags based on previous experience, but here is my test report.

For testing, I updated to the linux/6.8.0-32.32 generic kernel in noble-proposed. It seemed that I needed to reinstall the intel-ipu6-dkms after installing the kernel packages.

Overall, this is a huge improvement. The kernel detects the camera sensor and loads the ipu6 drivers. About half the time, the sensor is detected correctly and registered. Then, applications like vlc, zoom, gUM test in the browser all work reliably. Successful kernel messages look like (in part):

2024-05-06T17:26:42.688374-04:00 raven kernel: intel-ipu6-isys intel-ipu6-isys0: bind ov2740 3-0036 nlanes is 2 port is 1
2024-05-06T17:26:42.688378-04:00 raven kernel: intel-ipu6-isys intel-ipu6-isys0: All sensor registration completed.

And during operation:

2024-05-06T17:39:24.330879-04:00 raven kernel: intel-ipu6-isys intel-ipu6-isys0: stream on ov2740 3-0036

The other half of the time, there is a problem detecting the sensor and loading the module. When that happens, kernel messages are:

2024-05-06T17:11:53.825968-04:00 raven kernel: ov2740 i2c-INT3474:01: error -EIO: failed to find sensor
2024-05-06T17:11:53.825968-04:00 raven kernel: ov2740: probe of i2c-INT3474:01 failed with error -5

When this happens, reboot once or twice gets it back to the working state.

One time I noticed a seemingly correct boot, but when I tried to use the camera, it failed and I saw the following in the log:

2024-05-06T17:20:21.587753-04:00 raven kernel: intel-ipu6-isys intel-ipu6-isys0: stream on ov2740 3-0036
2024-05-06T17:20:21.730058-04:00 raven kernel: intel-ipu6-isys intel-ipu6-isys0: csi2-1 error: Payload checksum (CRC) error
2024-05-06T17:20:21.906327-04:00 raven kernel: intel-ipu6-isys intel-ipu6-isys0: csi2-1 error: Payload checksum (CRC) error
2024-05-06T17:20:21.906343-04:00 raven kernel: intel-ipu6-isys intel-ipu6-isys0: csi2-1 error: Transfer FIFO overflow
2024-05-06T17:20:21.906354-04:00 raven kernel: intel-ipu6-isys intel-ipu6-isys0: csi2-1 error: Frame sync error

And this is an error with the similar user-side symptoms but a different message:

2024-05-06T18:37:01.015739-04:00 raven kernel: intel-ipu6-isys intel-ipu6-isys0: stream on ov2740 3-0036
2024-05-06T18:37:01.135909-04:00 raven kernel: ov2740 i2c-INT3474:01: failed to reset
2024-05-06T18:37:03.183800-04:00 raven kernel: intel-ipu6-isys intel-ipu6-isys0: stream stop time out

In both of these failure cases, the driver was then hung and then camera was stuck until the next successful reboot.

No configuration or kernel packages were added or removed during these tests. Same kernel from noble-proposed:

$ uname -a
Linux raven 6.8.0-32-generic #32-Ubuntu SMP PREEMPT_DYNAMIC Wed May 1 15:30:59 UTC 2024 x86_64 x86_64 x86_64 GNU/Linux