Re: type-c subsystem is empty on Thinkpad T14 Gen 4 AMD

[Douglas Gilbert <dgilbert@interlog.com>]

On 12/17/23 11:21, Yaroslav Isakov wrote:
> Hello! I recently bought Thinkpad T14 Gen 4 AMD laptop, and I
> installed Gentoo on it, with kernel 6.6.4.
> 
> Even though type-c ports seems to be working (I checked usb3 flash
> stick, lenovo charger, Jabra headset, Yubikey), I cannot see any
> devices in /sys/class/(typec,typec_mux,usb_power_delivery).
> 
> There are no messages in dmesg at all, mentioning typec. I can see
> that modules typec_ucsi, ucsi_acpi, thunderbolt are loaded. I can see
> that device TYPEC000 is present on acpi bus, there are files in
> /sys/bus/acpi/devices/USBC000:00, but, there is no driver linked in
> it.
> 
> I tried to recompile module ucsi_acpi, with adding { "USBC000", 0 }
> to ucsi_acpi_match, but it did not change anything (except that in
> modinfo of this module, USBC000 is now seen.
> 
> I tried to decompile SSDT1 table, which has definition of USBC, but
> there is nothing in it, which is supicious.
> 
> What else can I check, to understand, why can't I see anything in
> typec/PD subsystems?
> 

I have a X13 Gen 3 [i5-1240P] which is about 18 months old. Everything you
mention is present plus the typec ports and the associated pd objects:

$ lsucpd
  port0 [pd0]  <<====  partner [pd2]
  port1 [pd1]  <

A power adapter is connected to port0. Here are the modules loaded:

$ lsmod | grep typec
typec_ucsi             57344  1 ucsi_acpi
roles                  16384  1 typec_ucsi
typec                 114688  1 typec_ucsi
usb_common             20480  4 xhci_hcd,usbcore,uvcvideo,typec_ucsi
$ lsmod | grep ucsi
ucsi_acpi              12288  0
typec_ucsi             57344  1 ucsi_acpi
roles                  16384  1 typec_ucsi
typec                 114688  1 typec_ucsi
usb_common             20480  4 xhci_hcd,usbcore,uvcvideo,typec_ucsi

$ ls /sys/bus/acpi/devices/USBC000:00
device:ac  device:ad  hid  modalias  path  physical_node  power  status 
subsystem  uevent  uid  wakeup

Strange that the Thunderbolt module is loaded since I thought only the Intel
variants supported Thunderbolt.

The only thing that I can think of is some BIOS setting. When I poked around
in the X13 BIOS I don't remember any setting that would cause what you are
seeing.]

Doug Gilbert