Re: [RFC PATCH 0/9] Add support for Microsoft Surface System Aggregator Module

[Maximilian Luz]

On 9/23/20 5:30 PM, Arnd Bergmann wrote:
> On Wed, Sep 23, 2020 at 5:15 PM Maximilian Luz <luzmaximilian@xxxxxxxxx> wrote:
> > Hello,
> >
> > The Surface System Aggregator Module (we'll refer to it as Surface
> > Aggregator or SAM below) is an embedded controller (EC) found on various
> > Microsoft Surface devices. Specifically, all 4th and later generation
> > Surface devices, i.e. Surface Pro 4, Surface Book 1 and later, with the
> > exception of the Surface Go series and the Surface Duo. Notably, it
> > seems like this EC can also be found on the ARM-based Surface Pro X [1].
>
> I think this should go to drivers/platform/x86 or drivers/platform/surface/
> along with other laptop vendor specific code rather than drivers/misc/.

I initially had this under drivers/platform/x86. There are two main
reasons I changed that: First, I think it's a bit too big for
platform/x86 given that it basically introduces a new subsystem. At this
point it's really less of "a couple of odd devices here and there" and
more of a bus-type thing. Second, with the possibility of future support
for ARM devices (Pro X, Pro X 2 which is rumored to come out soon), I
thought that platform/x86 would not be a good fit.

I'd be happy to move this to platform/surface though, if that's
considered a better fit and you're okay with me adding that. Would make
sense given that there's already a platform/chrome, which, as far as I
can tell, also seems to be mainly focused on EC support.

> I'll have a look at the code myself, but I'd prefer to have the maintainers
> for the other laptop drivers review this properly.

Thanks! I'll CC them for the next version.

Regards,
Max