Re: [PATCH] pmdomain: raspberrypi-power: add remove function

[Gregor Herburger]

On Thu, Jul 16, 2026 at 02:28:15PM +0200, Ulf Hansson wrote:
> On Wed, Jul 15, 2026 at 10:16 AM Gregor Herburger
> <gregor.herburger@xxxxxxxxxxxxx> wrote:
> >
> > The raspberrypi-power driver registers resources with
> > of_genpd_add_provider_onecell and pm_genpd_init but never removes them.
> > When the driver gets unbound and bound again this causes error. Add a
> > remove function to cleanup all registered resources.
> >
> > Signed-off-by: Gregor Herburger <gregor.herburger@xxxxxxxxxxxxx>
> > ---
> >  drivers/pmdomain/bcm/raspberrypi-power.c | 12 ++++++++++++
> >  1 file changed, 12 insertions(+)
> >
> > diff --git a/drivers/pmdomain/bcm/raspberrypi-power.c b/drivers/pmdomain/bcm/raspberrypi-power.c
> > index b87ea7adb7bea..2c2135c17afb0 100644
> > --- a/drivers/pmdomain/bcm/raspberrypi-power.c
> > +++ b/drivers/pmdomain/bcm/raspberrypi-power.c
> > @@ -232,6 +232,17 @@ static int rpi_power_probe(struct platform_device *pdev)
> >         return 0;
> >  }
> >
> > +static void rpi_power_remove(struct platform_device *pdev)
> > +{
> > +       struct rpi_power_domains *rpi_domains = platform_get_drvdata(pdev);
> > +       int nr_domains = RPI_POWER_DOMAIN_COUNT - 1;
> > +
> > +       of_genpd_del_provider(pdev->dev.of_node);
> > +
> > +       for (int i = nr_domains; i >= 0; i--)
> > +               pm_genpd_remove(&rpi_domains->domains[i].base);
> > +}
> > +
> >  static const struct of_device_id rpi_power_of_match[] = {
> >         { .compatible = "raspberrypi,bcm2835-power", },
> >         {},
> > @@ -244,6 +255,7 @@ static struct platform_driver rpi_power_driver = {
> >                 .of_match_table = rpi_power_of_match,
> >         },
> >         .probe          = rpi_power_probe,
> > +       .remove         = rpi_power_remove,
> 
> In general it's not a good idea to allow unbinding power domain
> drivers, as it will probably break consumers and their drivers.
> Although, I don't know whether it makes sense in this particular case.
> 
Ok. I stumbled on this when I was trying to fix an error in the remove path of
the raspberrypi-firmware driver. I have not checked if all the drivers still
work so you are probably right.

> Another option is to prevent user-space from unbinding by adding the below here:
> ".suppress_bind_attrs = true,"

That would be the simpler solution. If I add this for this driver, it should
also be added to raspberrypi-firmware and to bcm2835-mbox. Because without those
drivers this driver wouldn't work anyways. Should I add this to those drivers?
And remove the remove callbacks?
> 
> >  };
> >  builtin_platform_driver(rpi_power_driver);
> >
> 
> Kind regards
> Uffe

-- 
Gregor Herburger
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