Re: [Question] Upstreaming hwmon driver for Nuvoton NCT5584D (NDA / licensing inquiry)

Hi,

On 8/7/26 09:22, [email protected] wrote:
> Hi Roeck,
> 
> First, I would like to express my deep respect for your immense contributions to the Linux kernel, especially your extensive maintenance work on the hwmon subsystem and Nuvoton chip drivers.
> 
> I am currently interning at Colorful in Shenzhen, working on BIOS/UEFI development. I have prior experience in open-source development (mainly Neovim plugins), and I am now eager to contribute to the Linux kernel.
> 
> Recently, I have been working with the Nuvoton NCT5584D Super I/O chip and have experimentally written a working driver for hardware monitoring on our boards. However, because the hardware documentation is under NDA, I want to ensure I follow the strict legal and community guidelines before attempting to upstream any code.
> 
> Since I cannot directly share or reference non-public datasheets, I would greatly appreciate your guidance on the best way forward:
> 
> 1. Is it generally acceptable to upstream a clean-room driver for NCT5584D that only contains the minimal necessary register definitions (for temperature, voltage, fan monitoring/PWM) without attaching/referencing public datasheets?
> 2. Alternatively, should I attempt to contact Nuvoton directly to request permission/public datasheet release for upstreaming, or look into extending the existing nct6775 driver framework if the register layout allows?
> 
> My goal is to strictly abide by both community standards and NDA boundaries while contributing functional hardware support back to the Linux community.
> 
> Thank you for your time and advice. I look forward to hearing from you.
> 

 From what I can see online, it appears that NCT5584D is detected as NCT6799 by the
NCT6775 driver, meaning it is likely a shrink-down version of that chip. Given that,
and if the information is correct, a stand-alone driver is a no-go.

Have you tested if the nct6775 driver just works ?

As for the NDA and the rest of your questions, that is something you'll have to discuss
with Nuvoton. In general they are (or at least used to be) quite open to making their
datasheets available for purposes such as developing a Linux kernel driver. However,
there is one exception: If there is a two-way NDA that prevents them from doing that,
they obviously can not share the datasheet with third parties, making it all but
impossible to develop an open source driver. Either case, this is a legal question,
and I can not give legal advice.

Thanks,
Guenter