Re: How to use an ACPI declared GPIO in a userspace ...

Andy Shevchenko
2020-09-30T16:11:01Z

On Wed, Sep 30, 2020 at 6:54 PM Andy Shevchenko
<andy.shevchenko@gmail.com> wrote:
> On Wed, Sep 30, 2020 at 6:39 PM Flavio Suligoi <f.suligoi@asem.it> wrote:
> > > I guess you simply didn't get. The "gpio-line-names" property of GPIO
> > > *controller* (provider!) and you are trying to do something with the
> > > *consumer*
> > > if I got it right.
> > >
> > > And of course GPIO line, which has name, has no difference in use from
> > > another
> > > w/o name assigned. You will need to request it by *consumer* either in
> > > kernel
> > > or in user space.
> > >
> > > To be more precise we have to look at your DSDT.
>
> ^^^^^^^ **DSDT**.
>
> > My SSDT table is:
>
> ^^^^ See the difference? I can't help here.

There are two ways to get DSDT:
1. % cp -a /sys/firmware/acpi/tables /tmp/mytables; tar -cf
mytables.tar /tmp/mytables
2. % acpidump -o mytables.dat # preferable

> > So I need a "consumer", but I don't want to export the GPIO using its number...
> > If you have any suggestion ...
>
> Define "gpio-line-names" property in the *provider* (controller)
> device node _DSD().

--
With Best Regards,
Andy Shevchenko