People of Level 1, I need your help.
TLDR;
How can I list PD modes or the PDO’s of a device to check compatibility? Has anyone seen edge cases where only specific devices wouldn’t charge off of a source?
I picked up a Phillips 346b1c ultrawide monitor and it’s been a joy except that it won’t charge my Lenovo Yoga 730 13 when docked. If you boot the system with it docked you get a low wattage warning. I’ve pretty much ruled out the cables, I’ve tried the one in the box with the monitor and 2 known good TB3 cables. The monitor is rated for 90W PD and the laptop is rated for 45W so we are good there, I haven’t had issues with other monitors or various TB3 docks. What gets me is that once or twice I’ve gotten the laptop to charge, makes me think it might be a physical issue on the monitor. Everything works fine if I use a chromebook rated for 45W. The best information I can find says that the monitor is capable of up to 20V/4.5A and the most the laptop accepts is 20V/2.25A. My understanding is that PD will negotiate down to something appropriate but PD 2.0 relies on preset PDO’s, voltage and amperage combos available to the source and sink devices. Is there a way to check the PDO’s on a device through software? If you know anything let me know. I have a ticket running with Phillips support and will update if an RMA does or doesn’t resolve the issue.
Edit:
Tried testing with ubuntu 19.10
https://www.kernel.org/doc/Documentation/ABI/testing/sysfs-class-typec
I tried cat /sys/class/typec/port1/power_operation_mode to no avail, there are no ports available under /sys/class/typec/