Public bug reported: [Impact]
MIPI cameras do not work on affected Dell systems after updating to kernel 7.0.0-31-generic. The PSYS driver fails during probe. The camera stack cannot use the IPU7 processing system. CID: 202604-38584 Error log: ``` bus_add_device: cannot add device 'ipu7-psys0' to unregistered bus 'intel-ipu7-psys' intel-ipu7-psys ipu7-psys0: psys device_register failed intel_ipu7_psys.psys intel_ipu7.psys.40: probe with driver intel_ipu7_psys.psys failed with error -22 ``` The failure rate is 100% on the affected system. [Fix] Backport Intel commit `23cf17ab002dbb6b98da0e0dfa27ce2e4fe22a1f`: ``` media:ipu7: register psys node before add device ``` The patch registers the IPU7 PSYS private bus before it registers the auxiliary driver. It unregisters the bus if driver registration fails. It unregisters the driver before the bus during module removal. This fixes the PSYS driver bug exposed by kernel commit `086504bed2ebb` (`driver core: reject devices with unregistered buses`). That kernel change is present in 7.0.0-31 and absent from 7.0.0-29. Intel merged the fix on 2026-07-21. It is in the external `ipu7-drivers` repository and is not an upstream Linux kernel commit. The latest listed Intel tag, `20260629_2`, points to the parent of this fix, so no Intel release tag contains it yet. Upstream patch: https://github.com/intel/ipu7-drivers/commit/23cf17ab002dbb6b98da0e0dfa27ce2e4fe22a1f [Test Plan] 1. Install a kernel with the updated IPU7 PSYS module on a Dell system with an IPU7 MIPI camera. 2. Boot the system. 3. Check the PSYS driver state: ``` readlink -f /sys/bus/auxiliary/devices/intel_ipu7.psys.40/driver ls -l /sys/bus/intel-ipu7-psys/devices/ipu7-psys0 journalctl -k -b | grep -E 'IPU psys probe done|unregistered bus|psys device_register failed' ``` Without the patch, the boot log contains `unregistered bus` and `psys device_register failed`. The PSYS auxiliary device has no bound driver. With the patch, the log contains: ``` intel_ipu7_psys.psys intel_ipu7.psys.40: IPU psys probe done. ``` The PSYS auxiliary device binds to `intel_ipu7_psys.psys`. `ipu7-psys0` exists under `/sys/bus/intel-ipu7-psys/devices/`. Then open the camera application and capture a preview frame. The patch was built against 7.0.0-31-generic and hot-reloaded on CID 202604-38584. The PSYS driver bound and no new PSYS registration errors appeared. [Where problems could occur] The change affects IPU7 PSYS module load and unload paths. If the bus registration order is wrong, the PSYS module may fail to load. The boot log would show an auxiliary-driver probe failure. If module removal order is wrong, unloading `intel_ipu7_psys` could leave the private bus registered or access a removed bus. ** Affects: ipu7-drivers (Ubuntu) Importance: Undecided Status: New ** Affects: ipu7-drivers (Ubuntu Resolute) Importance: Undecided Assignee: AceLan Kao (acelankao) Status: In Progress ** Also affects: ipu7-drivers (Ubuntu Resolute) Importance: Undecided Status: New ** Changed in: ipu7-drivers (Ubuntu Resolute) Status: New => In Progress ** Changed in: ipu7-drivers (Ubuntu Resolute) Assignee: (unassigned) => AceLan Kao (acelankao) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2163373 Title: ipu7-psys module fails to probe To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ipu7-drivers/+bug/2163373/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
