[PATCH 1/1] usb: request only 8 bytes for USB_SPEED_FULL bMaxPacketSize0 discovery

[Marek Vasut]

On 9/26/22 09:34, Thomas Glanzmann wrote:
> Hallo Marek,

Hi,

>> Can you be more specific about those logitech receivers ? I might have one
>> of those devices, and I have DWC3 in i.MX8MP and i.MX8MQ, as well as ZynqMP,
>> so I should be able to try and trigger the problem. Can you share the
>> reproducer test case for this problem ?
> 
> I can reproduce the issue with Keychron K1 and Realforce keyboards on the
> usb-c port of my mac mini 2020 model running u-boot. The two keyboards
> don't work without Jannes patch. With Jannes patch, they work. Other
> keyboards like my Thinkpad compact keyboard work with and without the
> patch.
> 
> https://www.keychron.com/products/keychron-k1-wireless-mechanical-keyboard
> https://www.realforcekeyboards.com
> https://www.lenovo.com/de/de/accessories-and-monitors/keyboards-and-mice/keyboards/KEYBOARD-German/p/0B47202
> 

I can also reproduce it with the logitech unifying receiver on iMX8MP 
DWC3 controller, likely close to what Russell has (046d:c52b Version 18.16).

The same device does work on iMX8MM ChipIdea USB 2.0 controller.

I wonder if this might be specific to the DWC3 controller (driver?) 
somehow ?