Re: [PATCH 0/4] usb: usbtmc: fix undersized high-speed bulk packets on xHCI

[guido@kiener-muenchen.de]

Hi Nicolai,

The USBTMC protocol was defined by the IVI Foundation. The purpose of a 
specification is to ensure that manufacturers adhere to the agreed rules 
so that maximum compatibility between T&M instruments and client 
software (e.g. NI‑VISA, Keysight VISA, R&S VISA, etc.) is guaranteed.
The Linux USBTMC kernel driver is a class driver that has been tested by 
members of the IVI Foundation and ensures reliable communication with 
their devices. Therefore every manufacturer of USBTMC devices should 
comply with the specification and cannot expect bugs in device firmware 
to be fixed by patches to the USBTMC driver on Windows, Linux, or macOS.
If such an approach were tolerated, the development costs that one 
manufacturer omitted would be shifted onto and multiplied across all 
other manufacturers. If there is a demonstrable bug in the USBTMC kernel 
driver, we can certainly discuss fixing the driver. Otherwise I cannot 
support adding device‑specific patches to a class driver. Over time that 
would increase the driver’s complexity and encourage other manufacturers 
not to follow the jointly developed specification — something that would 
certainly not be acceptable for the TCP/IP stack either.

Best regards,

Guido Kiener