2

I've been having a bear of a time getting this new Lenovo Thikpad X1 Carbon Gen 9 to suspend. I think these are the lines that indicate the cause of my problem

systemd-sleep[682835]: System returned from sleep state. bluetoothd[829]: Controller resume with wake event 0x1 kernel: usb 3-3: new full-speed USB device number 120 using xhci_hcd kernel: PM: suspend exit

After seeing this I wanted to disable XHCI ACPI, because I've seen this suggested on the forums. I did this,

❯ acpitool -e | grep XHCI 7. XHCI S3 *enabled pci:0000:00:14.0ed pci:0000:00:14.0

And then I disabled 7 with sudo acpitool -W7. Now it shows *disabled and my laptop suspends. What does XHCI ACPI wake do? Is this needed?

Improve this question

1 Answer 1

Reset to default
4

XHCI, the extensible host controller interface, is a specification for USB host controllers. It allows a generic XHCI driver to control any XHCI-compliant USB host controller.

XHCI wake allows USB-connected devices to wake your system up from suspend. You only need it if you want that ability. You can find which USB device woke up your machine by paying attention to the line,

kernel: usb 3-3: new full-speed USB device number 120 using xhci_hcd

The usb 3-3 is in reference to the bus (first number) and device number (second number). You can see what device resides there with, lsusb -s 3:3 in this case you got back,

Bus 003 Device 003: ID 174f:2454 Syntek Integrated Camera

Which tells you the USB webcam (integrated), a Syntek Integrated Camera, is waking up your machine. Because it's a Thinkpad

Improve this answer
1

You must log in to answer this question.

Start asking to get answers

Find the answer to your question by asking.

Ask question

Explore related questions

See similar questions with these tags.