Score:2

How to debug USB-C Power Delivery?

in flag

I have a laptop that supports USB-C Power Delivery, a ThinkPad T470. Charging it via a Lenovo USB-C power cable works fine, so USB-C PD works in general on this laptop.

I also have a monitor with USB-C PD on it, the 24MD4KL-B. The monitor should support up to 85W PD, and charging my phone via USB-C works fine. However, I cannot get my laptop to charge from it. I'm using the USB-C PD cable that came with the monitor. The monitor will work as a second display, so it's not a dead cable.

I have determined that the kernel thinks everything should be working:

$ cat /sys/class/typec/port0/usb_power_delivery_revision
2
$ cat /sys/class/typec/port0-partner/supports_usb_power_delivery
yes

What further steps can I take to debug why my laptop is not charging via USB-C Power Delivery from the monitor?

ru flag
If your system is not charging via USB-C then it's likely that your system's hardware requires a certain amount of power to actually power via USB-C. It's likely that your monitor is not outputting enough wattage to trigger. Which is going to be something hardware related, not Ubuntu related, making debugging much harder.
ca flag
I dont have path `/sys/class/typec` at all. Ubuntu 20.04
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