Commit 241d2fb5 authored by Michal Suchanek's avatar Michal Suchanek Committed by Rob Herring
Browse files

of: Make OF framebuffer device names unique 

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 displays.

Also, fix a node refcounting issue when exiting the boot display loop.

cc: linuxppc-dev@lists.ozlabs.org
References: https://bugzilla.kernel.org/show_bug.cgi?id=216095


Fixes: 52b1b46c ("of: Create platform devices for OF framebuffers")
Reported-by: default avatarErhard F. <erhard_f@mailbox.org>
Suggested-by: default avatarThomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: default avatarMichal Suchanek <msuchanek@suse.de>
Link: https://lore.kernel.org/r/20230201162247.3575506-1-robh@kernel.org


[robh: Rework to avoid node refcount leaks]
Signed-off-by: default avatarRob Herring <robh@kernel.org>
parent 064e32dc

drivers/of/platform.c

+10 −2
Original line number Diff line number Diff line
@@ -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 = 0;

		int ret;



		/* Check if we have a MacOS display without a node spec */
@@ -555,16 +556,23 @@ static int __init of_platform_default_populate_init(void) 
			if (!of_get_property(node, "linux,opened", NULL) ||

			    !of_get_property(node, "linux,boot-display", NULL))

				continue;

			dev = of_platform_device_create(node, "of-display", NULL);

			dev = of_platform_device_create(node, "of-display.0", NULL);

			of_node_put(node);

			if (WARN_ON(!dev))

				return -ENOMEM;

			boot_display = node;

			display_number++;

			break;

		}

		for_each_node_by_type(node, "display") {

			char buf[14];

			const char *of_display_format = "of-display.%d";



			if (!of_get_property(node, "linux,opened", NULL) || node == boot_display)

				continue;

			of_platform_device_create(node, "of-display", NULL);

			ret = snprintf(buf, sizeof(buf), of_display_format, display_number++);

			if (ret < sizeof(buf))

				of_platform_device_create(node, buf, NULL);

		}



	} else {