Re: Cutiepi, serdevs, and right way to handle its power button

[Andy Shevchenko]

On Wed, Sep 21, 2022 at 07:17:07PM +0200, Pavel Machek wrote:
> On Wed 2022-09-21 17:45:33, Andy Shevchenko wrote:
> > On Tue, Sep 20, 2022 at 10:56:37PM +0200, Pavel Machek wrote:
> > > Hi!
> > > 
> > > Cutiepie is a small handheld tablet. It has embedded controller
> > > connected via serial to the main system, handling stuff such as power
> > > button and battery percentage. Currently they are using userland
> > > deamon for communication, but I believe that should eventually go into
> > > kernel.
> > > 
> > > For debugging, it would be really nice to be able to attach my module
> > > to given serdev. Is such thing possible? I see "[PATCH v2 00/19]
> > > Dynamically load/remove serdev devices via sysfs*" series
> > > (https://www.spinics.net/lists/linux-serial/msg30732.html) but I'm not
> > > sure if equivalent functionality exists in mainline kernel?
> > > 
> > > Is there some kind of similar hardware already supported by mainline?
> > > Using driver as a reference might be easier than starting from
> > > scratch.
> > 
> > Is it arm or x86 based tablet?
> 
> arm64, but CPU architecture really should not matter.

It makes sense on the usual practices done for the platform as a whole, e.g.
ACPI vs. DT. So, I believe this one is DT based.

-- 
With Best Regards,
Andy Shevchenko