mt9m114 webcam sensor power-up failed

[Luca Leonardo Scorcia]

On my ASUS T100TAM (old Bay Trail 2-in-1 laptop) the webcam is the last non-working piece of hardware. The following dmesg snippet seems to suggest that the kernel needs a special config flag:

[ 25.478178] atomisp_gmin_platform: module is from the staging directory, the quality is unknown, you have been warned.
[ 25.478274] atomisp_gmin_platform: module verification failed: signature and/or required key missing - tainting kernel
[ 25.508617] atomisp_mt9m114: module is from the staging directory, the quality is unknown, you have been warned.
[ 25.649601] mt9m114 i2c-INT33F0:00: gmin: power management provided via Crystal Cove PMIC (i2c addr 0x6e)
[ 25.649614] mt9m114 i2c-INT33F0:00: gmin_subdev_add: ACPI path is \_SB.I2C4.CAM0
[ 25.650170] mt9m114 i2c-INT33F0:00: Failed to find EFI variable INT33F0:00_ClkSrc
[ 25.650176] mt9m114 i2c-INT33F0:00: ClkSrc: using default (1)
[ 25.650508] mt9m114 i2c-INT33F0:00: Found DMI entry for 'INT33F0:00_CsiPort'
[ 25.650812] mt9m114 i2c-INT33F0:00: Found DMI entry for 'INT33F0:00_CsiLanes'
[ 25.650961] mt9m114 i2c-INT33F0:00: will handle gpio0 via ACPI
[ 25.651048] mt9m114 i2c-INT33F0:00: will handle gpio1 via ACPI
[ 25.651241] mt9m114 i2c-INT33F0:00: Failed to find EFI gmin variable gmin_V1P8GPIO
[ 25.651247] mt9m114 i2c-INT33F0:00: V1P8GPIO: using default (-1)
[ 25.651440] mt9m114 i2c-INT33F0:00: Failed to find EFI gmin variable gmin_V2P8GPIO
[ 25.651445] mt9m114 i2c-INT33F0:00: V2P8GPIO: using default (-1)
[ 25.651457] mt9m114 i2c-INT33F0:00: Will use CLK1 (pmc_plt_clk_1)
[ 25.651472] intel_soc_pmic_exec_mipi_pmic_seq_element: Not implemented
[ 25.651475] intel_soc_pmic_exec_mipi_pmic_seq_element: i2c-addr: 0x6e reg-addr 0x5d value 0x63 mask 0xff
[ 25.651480] mt9m114 i2c-INT33F0:00: ACPI didn't mapped the OpRegion needed to access I2C address 0x6e.
               Need to compile the kernel using CONFIG_*_PMIC_OPREGION settings
[ 25.651572] intel_soc_pmic_exec_mipi_pmic_seq_element: Not implemented
[ 25.651575] intel_soc_pmic_exec_mipi_pmic_seq_element: i2c-addr: 0x6e reg-addr 0x5d value 0x62 mask 0xff
[ 25.651579] mt9m114 i2c-INT33F0:00: ACPI didn't mapped the OpRegion needed to access I2C address 0x6e.
               Need to compile the kernel using CONFIG_*_PMIC_OPREGION settings
[ 25.651659] mt9m114 i2c-INT33F0:00: sensor power-up failed
[ 25.651691] INT33F0:00: mt9m114 power-up err

Is this something that could be considered for the next kernels? Can I preview test it somehow? Keep in mind that this laptop is pretty slow...

ProblemType: Bug
DistroRelease: Ubuntu 22.04
Package: linux-image-5.19.0-32-generic 5.19.0-32.33~22.04.1
ProcVersionSignature: Ubuntu 5.19.0-32.33~22.04.1-generic 5.19.17
Uname: Linux 5.19.0-32-generic x86_64
ApportVersion: 2.20.11-0ubuntu82.3
Architecture: amd64
CasperMD5CheckResult: pass
CurrentDesktop: ubuntu:GNOME
Date: Wed Feb 22 10:56:28 2023
InstallationDate: Installed on 2023-02-12 (9 days ago)
InstallationMedia: Ubuntu 22.04.1 LTS "Jammy Jellyfish" - Release amd64 (20220809.1)
SourcePackage: linux-signed-hwe-5.19
UpgradeStatus: No upgrade log present (probably fresh install)

[Luca Leonardo Scorcia (lscorcia)]

After further investigation, it seems the message is partially misleading. Power management for mt9m114 on ASUS T100 is indeed not implemented yet, but not because of a missing define - the necessary define is actually active in the kernel config. It is a kernel issue instead - apparently fixed by commit https://github.com/torvalds/linux/commit/73d15a7c13bfe1292db85ed3de8dfa711291819d which is not yet present in any mainline kernel (should be present in the next 6.3 release).

As a cautionary warning though audio is broken in mainline kernel 6.2.1 so the whack-a-mole game for Bay Trail devices may continue even with the next kernel :-)

[Luca Leonardo Scorcia (lscorcia)]

I can confirm that kernel 6.3-rc5 does load correctly the driver for mt9m114, however that's still not enough to use the webcam as /dev/video* devices do not get created at boot. Modules seem to load correctly. Maybe some more userspace work is needed in addition to the kernel driver? I have no idea on how to troubleshoot this further. Good news, audio is fixed.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Kostadin Stoilov (kmstoilov)]

I have a similar device with the same problem. Happy to help with troubleshooting, but no idea how to proceed.