Re: GPIO static allocation warning with v6.2-rcX

[Marco Felsch <m.felsch@xxxxxxxxxxxxxx>]

Hi Linus,

On 23-01-30, Linus Walleij wrote:
> On Sun, Jan 29, 2023 at 7:33 PM Robert Schwebel
> <r.schwebel@xxxxxxxxxxxxxx> wrote:
> 
> > While this could also be done with a daemon offering a dbus api, this
> > would be significantly more complex. In a critical environment, one
> > needs to make sure that the daemon process never fails, otherwhise the
> > power of the DuT would maybe be in a random state. Then of course one
> > can add a watchdog, but with the current sysfs interface it's really
> > simple. Of course that would also work if the new interface would offer
> > a "keep this line as it is" feature, but adding a dbus daemon just for
> > keeping the state of a pin sounds overcomplex when the kernel could also
> > provide that functionality.
> 
> One issue we face as developers is scaleability. Things that
> seem straight forward on a single board computer in a lab get
> really complex in a big system with man GPIO chips.
> 
> One of the big dangers of the sysfs ABI is that it is dependent on
> probe order which the kernel sadly does not really guarantee.

Does it? At least the drive I listed (e.g. the imx gpio driver) uses
aliases to make it reliable.

Regards,
  Marco