Re: [PATCH] of: Make of framebuffer devices unique

From: Michal Suchánek
Date: Wed Jan 18 2023 - 16:46:28 EST


On Wed, Jan 18, 2023 at 09:13:05PM +0100, Erhard F. wrote:
> On Tue, 17 Jan 2023 17:58:04 +0100
> Michal Suchanek <msuchanek@xxxxxxx> wrote:
>
> > Since Linux 5.19 this error is observed:
> >
> > sysfs: cannot create duplicate filename '/devices/platform/of-display'
> >
> > This is because multiple devices with the same name 'of-display' are
> > created on the same bus.
> >
> > Update the code to create numbered device names for the non-boot
> > disaplay.
> >
> > cc: linuxppc-dev@xxxxxxxxxxxxxxxx
> > References: https://bugzilla.kernel.org/show_bug.cgi?id=216095
> > Fixes: 52b1b46c39ae ("of: Create platform devices for OF framebuffers")
> > Reported-by: Erhard F. <erhard_f@xxxxxxxxxxx>
> > Suggested-by: Thomas Zimmermann <tzimmermann@xxxxxxx>
> > Signed-off-by: Michal Suchanek <msuchanek@xxxxxxx>
> > ---
> > drivers/of/platform.c | 8 +++++++-
> > 1 file changed, 7 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/of/platform.c b/drivers/of/platform.c
> > index 81c8c227ab6b..f2a5d679a324 100644
> > --- a/drivers/of/platform.c
> > +++ b/drivers/of/platform.c
> > @@ -525,6 +525,7 @@ static int __init of_platform_default_populate_init(void)
> > if (IS_ENABLED(CONFIG_PPC)) {
> > struct device_node *boot_display = NULL;
> > struct platform_device *dev;
> > + int display_number = 1;
> > int ret;
> >
> > /* Check if we have a MacOS display without a node spec */
> > @@ -561,10 +562,15 @@ static int __init of_platform_default_populate_init(void)
> > boot_display = node;
> > break;
> > }
> > +
> > for_each_node_by_type(node, "display") {
> > + char *buf[14];
> > if (!of_get_property(node, "linux,opened", NULL) || node == boot_display)
> > continue;
> > - of_platform_device_create(node, "of-display", NULL);
> > + ret = snprintf(buf, "of-display-%d", display_number++);
> > + if (ret >= sizeof(buf))
> > + continue;
> > + of_platform_device_create(node, buf, NULL);
> > }
> >
> > } else {
> > --
> > 2.35.3
> >
>
> Thank you for the patch Michal!
>
> It applies on 6.2-rc4 but I get this build error with my config:

Indeed, it's doubly bad.

Where is the kernel test robot when you need it?

It should not be that easy to miss this file but clearly it can happen.

I will send a fixup.

Sorry about the mess.

Thanks

Michal