Public bug reported:
This is the summary of a long conversation I had with Claude Sonnet AI
regarding the missing MIPI webcam support. I do not know if it
hallucinates or not, but this looks much more precise and specific than
the diagnosis I could find online.
== Summary ==
The built-in MIPI webcam (OmniVision ov01a10) on the Dell Precision 5490
does not work because mei-vsc-hw does not include ACPI HID INTC10CF in
its match table. This HID is used by the Intel Visual Sensing Controller
(IVSC) on this machine, and without it the entire IPU6 camera stack
cannot initialize.
== System ==
- Machine: Dell Precision 5490
- Kernel: 6.17.0-1012-oem (linux-image-oem-24.04, latest available as of March
2026)
- IPU6 PCI device: 8086:7d19 (IPU6EPMTL) at 0000:00:05.0
- Camera sensor: OmniVision ov01a10
- All required userspace packages installed: libcamhal-ipu6epmtl,
gstreamer1.0-icamera, v4l2-relayd
== ACPI topology ==
The IVSC chip is enumerated under the SPI-FD controller:
INTC10D0:00 → path: \_SB_.PC00.SPFD (SPI-FD controller)
INTC10CF:00 → path: \_SB_.PC00.SPFD.CVFD (IVSC chip, child of SPFD)
Modalias of INTC10CF:00: acpi:INTC10CF:
Physical node: platform/INTC10CF:00
Driver bound: none
== Root cause ==
mei-vsc-hw only matches the following ACPI HIDs:
acpi*:INTC1009:*
acpi*:INTC1058:*
acpi*:INTC1094:*
acpi*:INTC10D0:*
INTC10CF is not in the list. As a result:
1. mei-vsc-hw never probes INTC10CF:00
2. No intel_vsc platform device is created
3. mei-vsc has nothing to bind to
4. ivsc_ace and ivsc_csi load but create no MEI devices
5. ipu_bridge never gets a CSI device
6. intel-ipu6 (0000:00:05.0) hangs indefinitely waiting for its IVSC supplier
7. Webcam is completely non-functional
== Required firmware files ==
All required firmware files are present:
/lib/firmware/intel/vsc/ivsc_fw.bin.zst
/lib/firmware/intel/vsc/ivsc_pkg_ovti01a0_0.bin.zst
/lib/firmware/intel/vsc/ivsc_skucfg_ovti01a0_0_1.bin.zst
/lib/firmware/intel/ipu/ipu6epmtl_fw.bin.zst
== Proposed fix ==
Add INTC10CF to the ACPI match table in drivers/misc/mei/mei-vsc-hw.c:
static const struct acpi_device_id mei_vsc_hw_acpi_ids[] = {
{ "INTC1009", 0 },
{ "INTC1058", 0 },
{ "INTC1094", 0 },
{ "INTC10CF", 0 }, /* <-- add this line */
{ "INTC10D0", 0 },
{ }
};
This is consistent with how other IVSC HID variants have been added
previously.
== References ==
- Intel IPU6 driver: drivers/media/pci/intel/
- IVSC drivers: drivers/media/pci/intel/ivsc/
- MEI VSC driver: drivers/misc/mei/mei-vsc-hw.c
- Similar past fix adding INTC10D0:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
== Impact ==
All Dell Precision 5490 laptops running Ubuntu with the OEM kernel are
affected. The webcam is completely non-functional out of the box with no
workaround available without recompiling the kernel module.
** Affects: linux-oem-6.17 (Ubuntu)
Importance: Undecided
Status: New
** Tags: dell-precision mipi webcam
--
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.
https://bugs.launchpad.net/bugs/2144014
Title:
mei-vsc-hw: missing ACPI HID INTC10CF prevents webcam from working on
Dell Precision 5490
To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux-oem-6.17/+bug/2144014/+subscriptions
--
ubuntu-bugs mailing list
[email protected]
https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
