With the same Xbox cable but with a proper charger, does it work?
Most of the time, you avoid problems of "PD device hierarchy" by using a proper charger (i.e. a device that only has the functionality to charge other devices).
> Most of the time, you avoid problems of "PD device hierarchy" by using a proper charger (i.e. a device that only has the functionality to charge other devices).
The problem is with the "most", which means you can't count on it.
I have usb-c headphones that can be charged with my hp usb-c laptop charger (which is a "proper charger", I guess, since it only does charging) or from a regular computer usb port. They don't pretend to have any high-powered charge mode (manual says 3 hour charge time and "usb charging").
My usb-c ecig won't charge from that. It will only charge from either my pc's usb-a port or random "low power" usb phone charger.
I haven't tested it with any of the fancier high-powered adapters, since I don't own any. But, clearly, usb-c charging ports are not that universal.
Sure, as a technically inclined user, I can understand that.
It actually is a Chinese brand, but not some one-off brand bought off Ali Express. It's a device bought from a reputable store in France with a name that I've seen around for several years (Vaporesso). Sure, that fact, in and of itself, is not enough to guarantee that corners haven't been cut and that the product is actually up to spec.
But, as a random consumer, how am I to know that it's "a pretend USB-C"? It looks exactly the same as my headphones, comes with the exact same-looking cable. There are no markings on it. The usb-c ports on my laptop have a bolt icon next to them, but its usb-c charger doesn't have any marking. They also don't say it shouldn't be used with anything other than the laptop it came with, and actually is able to charge my headphones and my mom's usb-c phone.
Even though I've kinda followed the talks about PD, negotiation, etc. its still not clear to me why this particular combination doesn't work. I was under the impression that, lacking any negotiation, ports should default to the basic 5V 500mA. So my fat laptop charger should be able to at least trickle-charge the e-cig.
Because USB-C does not have a defined "upstream" and "downstream" side of the cable, a user could connect two chargers together. This is obviously a bad idea.
To prevent this, a USB-C charger is only allowed to provide power on the cable once it senses a downstream device on the other side. A legacy USB-A to USB-C cable always applies power, though, as this does not provide any danger.
Some low-quality brands think they are smart and leave out the two $0.001 resistors needed for the device to advertise itself. This means it will only work with a USB-A to USB-C cable, and not a real USB-C charger.
Using the Xbox controller cable with an actual charger does work. The confusion came with how the PC delivers power to the controller but not the headset.
It’s ultimately not a big deal, and it’s surely something I can learn to intuit. But I think lots of consumers (I think about my poor mother) would benefit from a clearer labeling scheme on the various devices, ports, chargers, or cables.
Most of the time, you avoid problems of "PD device hierarchy" by using a proper charger (i.e. a device that only has the functionality to charge other devices).