Ciao Salvatore,
thanks a lot for replying...
On Thu, 1 Oct 2026, Salvatore Bonaccorso wrote:
On Thu, Oct 01, 2026 at 10:57:10AM +0200, Tomas Pospisek wrote:
Package: src:linux
Version: 6.12.107-1
Followup-For: Bug #1145131
X-Debbugs-Cc: [email protected]
User: [email protected]
Usertags: amd64
Control: found -1 6.12.107-1
Dear Debian kernel maintainers,
I have the same problem as the original reporter: I attach my laptop to
a beamer via the USB-C Display Port and nothing happens.
This worked in bookworm, so this is a regression from bookworm to trixie.
Could you please enable the TYPEC_MUX_INTEL_PMC and INTEL_SCU_PLATFORM
kernel modules in the trixie stable series kernel as well?
Were you able to test this fixes your problem?
No, I was not. I wanted to install the 7.x kernel from unstable that
contains those modules, but it requires linux-base from unstable and
that maybe pulls in other stuff... which made me back off from that.
I've also compiled those modules for my current trixie kernel from Debian
sources but I can't insmod those due missing Secure Boot signatures. I
have no idea about Secure Boot, so I've backed off from this as well for
the moment.
In case I'd be trivial for you to flip those two config flags, type
`make` and send those two modules to me then I could test those - see
below.
FWIW symptoms: when I plug in a display into the Display Port then
there's no reaction at all from the kernel. No message in `dmesg` at
all.
I want to re-test with the bookworm kernel since it does contain the
modules in question ...
$ dpkg -L linux-image-6.1.0-53-amd64 | grep pmc | grep intel
/lib/modules/6.1.0-53-amd64/kernel/drivers/mfd/intel_pmc_bxt.ko
/lib/modules/6.1.0-53-amd64/kernel/drivers/platform/x86/intel/pmc
/lib/modules/6.1.0-53-amd64/kernel/drivers/platform/x86/intel/pmc/intel_pmc_core.ko
/lib/modules/6.1.0-53-amd64/kernel/drivers/platform/x86/intel/pmc/intel_pmc_core_pltdrv.ko
... just to make sure it's not a broken hardware port.
However I can't test at the moment, since I do not own a Display Port
device myself - the problem occured at a location where I had to give a
presentation.
Hopefully I'll get a hand on a Display Port to HDMI adapter this weekend,
then I'll be able to test. Otherwise I'll be at the same presentation
location next Tuesday and I'll be able to test there for maybe an hour...
Thank you & best greetings!
*t
