Re: [PATCH v7 1/8] of/platform: Allow overlays to create platform devices from the root node

[Geert Uytterhoeven <geert@linux-m68k.org>]

On Tue, Jul 16, 2024 at 11:48 AM Geert Uytterhoeven
<geert@linux-m68k.org> wrote:
> On Wed, Jul 10, 2024 at 10:14 PM Stephen Boyd <sboyd@kernel.org> wrote:
> > We'd like to apply overlays to the root node in KUnit so we can test
> > platform devices created as children of the root node.
> >
> > On some architectures (powerpc), the root node isn't marked with
> > OF_POPULATED_BUS. If an overlay tries to modify the root node on these
> > platforms it will fail, while on other platforms, such as ARM, it will
> > succeed. This is because the root node is marked with OF_POPULATED_BUS
> > by of_platform_default_populate_init() calling
> > of_platform_default_populate() with NULL as the first argument.
> >
> > Loosen the requirement here so that platform devices can be created for
> > nodes created as children of the root node via DT overlays even if the
> > platform bus wasn't populated for the root node.
> >
> > Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
> > Cc: Saravana Kannan <saravanak@google.com>
> > Signed-off-by: Stephen Boyd <sboyd@kernel.org>

> > --- a/drivers/of/platform.c
> > +++ b/drivers/of/platform.c
> > @@ -732,11 +732,14 @@ static int of_platform_notify(struct notifier_block *nb,
> >         struct of_reconfig_data *rd = arg;
> >         struct platform_device *pdev_parent, *pdev;
> >         bool children_left;
> > +       struct device_node *parent;
> >
> >         switch (of_reconfig_get_state_change(action, rd)) {
> >         case OF_RECONFIG_CHANGE_ADD:
> > -               /* verify that the parent is a bus */
> > -               if (!of_node_check_flag(rd->dn->parent, OF_POPULATED_BUS))
> > +               parent = rd->dn->parent;
> > +               /* verify that the parent is a bus (or the root node) */
> > +               if (!of_node_is_root(parent) &&
> > +                   of_node_check_flag(parent, OF_POPULATED_BUS))
>
> Oh, you inverted the check for of_node_check_flag(); was that
> intentional?  Re-adding the "!" fixes all issues for me.

I have sent a fix.
https://lore.kernel.org/a9ada686e1f1c6f496e423deaf108f1bcfd94d7d.1721123679.git.geert+renesas@glider.be/

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds