Re: git: cda31e734925 - main - xhci(4): Ensure the so-called data toggle gets properly reset.

From: Nathan Whitehorn <nwhitehorn_at_freebsd.org>
Date: Tue, 03 May 2022 11:21:56 UTC
On 5/3/22 02:40, Hans Petter Selasky wrote:
> On 5/3/22 00:25, Nathan Whitehorn wrote:
>> After this change, I cannot use devices attached to the USB 3 hub in 
>> my Dell monitor anymore. The hub appears properly, but any device 
>> plugged into it just leaves this in dmesg:
>> ugen0.3: <Unknown > at usbus0 (disconnected)
>>
>> Note that there is no corresponding connected message or anything else.
>>
>> This is with an AMD XHCI controller:
>> xhci0@pci0:2:0:0:       class=0x0c0330 rev=0x02 hdr=0x00 
>> vendor=0x1022 device=0x43bb subvendor=0x1b21 subdevice=0x1142
>>      vendor     = 'Advanced Micro Devices, Inc. [AMD]'
>>      device     = '300 Series Chipset USB 3.1 xHCI Controller'
>>
>
>
> Hi Nathan,
>
> There is an ongoing discussion at (where you may upload USB debug logs 
> from the XHCI controller).
>
> https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=262882
>
> Can you try to "usbreset -d ugenX.Y" where ugenX.Y corresponds to the 
> address of the parent USB HUB for these devices. Do the devices come 
> back?
>
> I'm currently mostly testing on Intel chipsets, and don't see any such 
> issues!
>
> I believe the patch is correct, but maybe needs to be adapted to AMD's 
> XHCI controllers.
>
> --HPS
>

Yes, resetting the hub makes the devices appear and work. I'll add 
relevant details to the bug -- happy to test or investigate patches as well.
-Nathan