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bavariancake / XPS9570-macOS

macOS Mojave/Catalina on Dell XPS 9570.
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Investigate USB power property injection #37

Open ericdevjs opened 5 years ago

ericdevjs commented 5 years ago

Hi,

I bought this hub : https://www.amazon.ca/dp/B01MY35S2D/ref=pe_3034960_233709270_TE_item but when I plug it it nothing happens, even after restarting and it did not show up in system reports either.

Is the USB-C port supposed to work ?

THanks

bavariancake commented 5 years ago

The USB-C port works in USB high-speed/480mbps mode. I believe it doesn't work in super-speed/5gbps mode currently. This probably has something to do with the fact that it's also a Thunderbolt controller, which requires more work. If the hub insists on super-speed mode, it may seem like nothing is plugged in.

when I plug it it nothing happens

What happens in Windows?

Are you charging your computer through the hub? If so, does USB-C charging work?

ericdevjs commented 5 years ago

After rebooting a couple of times it finally worked but my external hard drive doesn't mount when connected to the hub but any other peripherals like mouse, audio interface or USB key are working correctly.

bavariancake commented 5 years ago

Is the drive self-powered? Most drives are running near the current limit of what USB can provide, so if you have a hub in the middle that takes some of that current away, you may find the drive will stop working. Check the USB -> Current Available / Current Required sections of System Info with the drive, hub, and other attached devices. Try a very short USB cable to the drive, since just the voltage drop on a longer cable can cause a drive to not get enough power. Test with and without your hub's power adapter.

If your drive works without the hub, it's most likely the hub or the interaction between the two. Unfortunately most USB hubs aren't exactly high quality or well tested.

It's possible that the USB C port is not delivering as much power as it could, and you could look into USB power property injection. You would need to ensure that you're not setting these limits beyond what the physical port on the XPS 9570 could handle (maybe it's protected by a polyfuse, but I would not want to find out the hard way). If you do go this route, and pull request would be welcome.

I'll rename this issue and leave it open for anyone that wants to work on this.