linux-kernel - [PATCH v5 2/2] PCI: Adjust visibility of boot

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Message-ID: <20250722041051.3354121-3-superm1@kernel.org>
Date: Mon, 21 Jul 2025 23:10:51 -0500
From: Mario Limonciello <superm1@...nel.org>
To: David Airlie <airlied@...il.com>,
	Bjorn Helgaas <bhelgaas@...gle.com>
Cc: Alex Deucher <alexander.deucher@....com>,
	Christian König <christian.koenig@....com>,
	Simona Vetter <simona@...ll.ch>,
	Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>,
	Maxime Ripard <mripard@...nel.org>,
	Thomas Zimmermann <tzimmermann@...e.de>,
	dri-devel@...ts.freedesktop.org (open list:DRM DRIVERS),
	linux-kernel@...r.kernel.org (open list),
	linux-pci@...r.kernel.org (open list:PCI SUBSYSTEM),
	Daniel Dadap <ddadap@...dia.com>,
	Mario Limonciello <mario.limonciello@....com>,
	Stephen Rothwell <sfr@...b.auug.org.au>
Subject: [PATCH v5 2/2] PCI: Adjust visibility of boot_display attribute instead of creation

From: Mario Limonciello <mario.limonciello@....com>

There is a desire to avoid creating new sysfs files late, so instead
of dynamically deciding to create the boot_display attribute, make
it static.

This also fixes a compilation failure when compiled without
CONFIG_VIDEO on sparc.

Reported-by: Stephen Rothwell <sfr@...b.auug.org.au>
Closes: https://lore.kernel.org/linux-next/20250718224118.5b3f22b0@canb.auug.org.au/
Signed-off-by: Mario Limonciello <mario.limonciello@....com>
---
v5
 * Fixups for comma and CONFIG_VIDEO
 * Drop sysfs_update_group() as it's no longer needed
 * Drop pointers in pci_boot_display_visible()
v3:
 * Move to pci_sysfs_init()
v2:
 * Change to sysfs_update_group() instead
---
 drivers/pci/pci-sysfs.c | 58 ++++++++++++++---------------------------
 1 file changed, 20 insertions(+), 38 deletions(-)

diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index 6b1a0ae254d3a..f5d98795a12fe 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -1059,37 +1059,6 @@ void pci_remove_legacy_files(struct pci_bus *b)
 }
 #endif /* HAVE_PCI_LEGACY */
 
-/**
- * pci_create_boot_display_file - create a file in sysfs for @dev
- * @pdev: dev in question
- *
- * Creates a file `boot_display` in sysfs for the PCI device @pdev
- * if it is the boot display device.
- */
-static int pci_create_boot_display_file(struct pci_dev *pdev)
-{
-#ifdef CONFIG_VIDEO
-	if (video_is_primary_device(&pdev->dev))
-		return sysfs_create_file(&pdev->dev.kobj, &dev_attr_boot_display.attr);
-#endif
-	return 0;
-}
-
-/**
- * pci_remove_boot_display_file - remove the boot display file for @dev
- * @pdev: dev in question
- *
- * Removes the file `boot_display` in sysfs for the PCI device @pdev
- * if it is the boot display device.
- */
-static void pci_remove_boot_display_file(struct pci_dev *pdev)
-{
-#ifdef CONFIG_VIDEO
-	if (video_is_primary_device(&pdev->dev))
-		sysfs_remove_file(&pdev->dev.kobj, &dev_attr_boot_display.attr);
-#endif
-}
-
 #if defined(HAVE_PCI_MMAP) || defined(ARCH_GENERIC_PCI_MMAP_RESOURCE)
 /**
  * pci_mmap_resource - map a PCI resource into user memory space
@@ -1691,17 +1660,30 @@ static const struct attribute_group pci_dev_resource_resize_group = {
 	.is_visible = resource_resize_is_visible,
 };
 
-int __must_check pci_create_sysfs_dev_files(struct pci_dev *pdev)
+static struct attribute *pci_display_attrs[] = {
+	&dev_attr_boot_display.attr,
+	NULL
+};
+
+static umode_t pci_boot_display_visible(struct kobject *kobj,
+					struct attribute *a, int n)
 {
-	int retval;
+	if (video_is_primary_device(kobj_to_dev(kobj)))
+		return a->mode;
 
+	return 0;
+}
+
+static const struct attribute_group pci_display_attr_group = {
+	.attrs = pci_display_attrs,
+	.is_visible = pci_boot_display_visible,
+};
+
+int __must_check pci_create_sysfs_dev_files(struct pci_dev *pdev)
+{
 	if (!sysfs_initialized)
 		return -EACCES;
 
-	retval = pci_create_boot_display_file(pdev);
-	if (retval)
-		return retval;
-
 	return pci_create_resource_files(pdev);
 }
 
@@ -1716,7 +1698,6 @@ void pci_remove_sysfs_dev_files(struct pci_dev *pdev)
 	if (!sysfs_initialized)
 		return;
 
-	pci_remove_boot_display_file(pdev);
 	pci_remove_resource_files(pdev);
 }
 
@@ -1845,6 +1826,7 @@ static const struct attribute_group pcie_dev_attr_group = {
 
 const struct attribute_group *pci_dev_attr_groups[] = {
 	&pci_dev_attr_group,
+	&pci_display_attr_group,
 	&pci_dev_hp_attr_group,
 #ifdef CONFIG_PCI_IOV
 	&sriov_pf_dev_attr_group,
-- 
2.48.1