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Sergey Zagursky
856c562c94
Since commitc6b1b34b50("media: pci: intel: Add CVS support for IPU bridge driver") the internal camera no longer works on laptops where the sensor sits behind an IVSC, for example a Dell XPS 16 9640 (IPU6, INTC10CF, ov02c10): intel-ipu6 0000:00:05.0: Found supported sensor OVTI02C1:00 intel-ipu6 0000:00:05.0: Connected 1 cameras ivsc_csi intel_vsc-92335fcf-3203-4472-af93-7b4453ac29da: mei-csi probed without device fwnode! No sensor subdevice is registered, the media graph has no sensor entity and userspace finds no camera at all. ipu_bridge_get_ivsc_csi_dev() first looks for the platform device named "intel_vsc" and returns its mei-csi child. That device is created by mei_vsc, which on this machine only appears once the LJCA USB bridge and its SPI controller have probed, about a second after the IPU6 probe that runs the bridge: 07:59:29.297 platform INTC10CF:00 created (ACPI scan) 07:59:41 intel-ipu6 probe -> ipu_bridge_init() 07:59:42.391 platform intel_vsc created (mei_vsc) The commit above added two fallbacks for CVS which match on the ACPI companion alone. They are reached for every entry of ivsc_acpi_ids[], IVSC IDs included. The IVSC ACPI device has two physical nodes: INTC10CF:00/physical_node -> platform/INTC10CF:00 (no driver bound) INTC10CF:00/physical_node1 -> platform/intel_vsc (mei_vsc) so bus_find_device_by_acpi_dev(&platform_bus_type, adev) returns the bare platform device. ipu_bridge_instantiate_ivsc() then attaches the IVSC software node to that device instead of to the mei-csi client, the bridge reports success, and the probe is never retried. mei_csi later probes without a fwnode, the CSI-2 link is never described, and the sensor ACPI device, which has an honoured _DEP on the IVSC device, is never enumerated. Before those fallbacks existed the lookup returned NULL here, the bridge failed with -ENODEV and the probe was retried once the IVSC device had shown up. Skip those fallbacks for IVSC devices, keying on the IVSC IDs rather than the CVS ones: new CVS IDs keep being added, whereas the IVSC list is complete. CVS binds a driver to the ACPI device itself, so matching on the companion stays unambiguous there. Fixes:c6b1b34b50("media: pci: intel: Add CVS support for IPU bridge driver") Link: https://lore.kernel.org/linux-media/20260901194526.6369-1-gvozdoder@gmail.com/ Cc: stable@vger.kernel.org Assisted-by: Claude Code:claude-opus-5 Signed-off-by: Sergey Zagursky <gvozdoder@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>