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From:   Michal Suchanek <msuchanek@suse.de>
Cc:     Michal Suchanek <msuchanek@suse.de>,
        Rob Herring <robh+dt@kernel.org>,
        Frank Rowand <frowand.list@gmail.com>,
        Thomas Zimmermann <tzimmermann@suse.de>,
        Javier Martinez Canillas <javierm@redhat.com>,
        devicetree@vger.kernel.org (open list:OPEN FIRMWARE AND FLATTENED
        DEVICE TREE), linux-kernel@vger.kernel.org (open list),
        linuxppc-dev@lists.ozlabs.org, "Erhard F ." <erhard_f@mailbox.org>
Subject: [PATCH] of: Make of framebuffer devices unique
Date:   Tue, 17 Jan 2023 17:58:04 +0100
Message-Id: <20230117165804.18036-1-msuchanek@suse.de>
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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@lists.ozlabs.org
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@mailbox.org>
Suggested-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Michal Suchanek <msuchanek@suse.de>
---
 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