Re: [PATCH v1 1/6] hwmon/misc: amd-sbi: Move core SBTSI support from hwmon to misc
From: gregkh@xxxxxxxxxxxxxxxxxxx
Date: Fri Mar 27 2026 - 03:25:29 EST
On Thu, Mar 26, 2026 at 10:52:29PM -0700, Guenter Roeck wrote:
> On 3/26/26 22:07, Gupta, Akshay wrote:
> >
> > On 3/24/2026 5:03 PM, Guenter Roeck wrote:
> > > Caution: This message originated from an External Source. Use proper caution when opening attachments, clicking links, or responding.
> > >
> > >
> > > On 3/24/26 03:36, Gupta, Akshay wrote:
> > > > On 3/23/2026 7:45 PM, Guenter Roeck wrote:
> > > > > Caution: This message originated from an External Source. Use proper caution when opening attachments, clicking links, or responding.
> > > > >
> > > > >
> > > > > On 3/23/26 04:08, Akshay Gupta wrote:
> > > > > > From: Prathima <Prathima.Lk@xxxxxxx>
> > > > > >
> > > > > > Move SBTSI core functionality out of the hwmon-only path and into
> > > > > > drivers/misc/amd-sbi so it can be reused by non-hwmon consumers.
> > > > > >
> > > > > > This split prepares the driver for additional interfaces while keeping
> > > > > > hwmon support as an optional layer on top of common SBTSI core logic.
> > > > > >
> > > > > This moves the driver out of hwmon space into misc/amd-sbi which,
> > > > > in my opinion, is completely unnecessary to accomplish the stated goals.
> > > > >
> > > > > I assume this is to be able to make changes which do not follow
> > > > > the hwmon ABI and/or to bypass hwmon subsystem review, similar
> > > > > to what has been done by others.
> > > > >
> > > > > Obviously, I think this is a bad idea. I won't give it a NACK,
> > > > > but I won't approve (nor review) it either.
> > > > >
> > > > > Guenter
> > > > Hi Guenter,
> > > >
> > > > Thank you for your quick response.
> > > >
> > > > At present, TSI supports a range of functionalities that cannot be exposed through hwmon. Additionally, a new protocol leveraging the TSI endpoint in hardware has been introduced, which, to our understanding, cannot be accommodated within the hwmon subsystem.
> > > >
> > > > Since we already support the RMI interface via misc/amd-sbi, we believe this remains the appropriate place to continue AMD's out-of-band support.
> > > >
> > > > I will update the commit message and cover letter to clearly articulate the rationale behind this change.
> > > >
> > > > Thank you
> > > >
> > > That is neither a reason or an argument for moving _hwmon_ part of the code
> > > out of the hwmon subsystem.
> > Following feedback from the Greg and MFD subsystem maintainers, we introduced an sb-rmi driver under misc/ that calls devm_hwmon_device_register_with_info(). We are considering the same approach for the sb-tsi driver. Would you recommend a more suitable alternative?
>
> I would have suggested to use an auxiliary driver, similar to PECI,
> but who am I to argue if senior maintainers suggest otherwise.
Sounds like an aux driver makes sense to me too, I don't remember saying
that you HAD to call devm_hwmon_device_register_with_info(), where was
that stated in previous reviews?
thanks,
greg k-h