[PATCH v3 3/4] PCI/VGA: only deal with VGA class devices

From: Sui Jingfeng <15330273260@189.cn>
To: Alex Deucher <alexander.deucher@amd.com>,
	Christian Konig <christian.koenig@amd.com>,
	Pan Xinhui <Xinhui.Pan@amd.com>, David Airlie <airlied@gmail.com>,
	Daniel Vetter <daniel@ffwll.ch>,
	Jani Nikula <jani.nikula@linux.intel.com>,
	Joonas Lahtinen <joonas.lahtinen@linux.intel.com>,
	Rodrigo Vivi <rodrigo.vivi@intel.com>,
	Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>,
	Ben Skeggs <bskeggs@redhat.com>,
	Karol Herbst <kherbst@redhat.com>, Lyude Paul <lyude@redhat.com>,
	Bjorn Helgaas <bhelgaas@google.com>,
	Alex Williamson <alex.williamson@redhat.com>,
	Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
	Maxime Ripard <mripard@kernel.org>,
	Thomas Zimmermann <tzimmermann@suse.de>,
	Hawking Zhang <Hawking.Zhang@amd.com>,
	Mario Limonciello <mario.limonciello@amd.com>,
	Lijo Lazar <lijo.lazar@amd.com>,
	YiPeng Chai <YiPeng.Chai@amd.com>,
	Andrey Grodzovsky <andrey.grodzovsky@amd.com>,
	Somalapuram Amaranath <Amaranath.Somalapuram@amd.com>,
	Bokun Zhang <Bokun.Zhang@amd.com>,
	Ville Syrjala <ville.syrjala@linux.intel.com>,
	Li Yi <liyi@loongson.cn>, Sui Jingfeng <suijingfeng@loongson.cn>,
	Jason Gunthorpe <jgg@ziepe.ca>, Kevin Tian <kevin.tian@intel.com>,
	Cornelia Huck <cohuck@redhat.com>,
	Yishai Hadas <yishaih@nvidia.com>,
	Abhishek Sahu <abhsahu@nvidia.com>, Yi Liu <yi.l.liu@intel.com>
Cc: amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org,
	linux-kernel@vger.kernel.org, intel-gfx@lists.freedesktop.org,
	nouveau@lists.freedesktop.org, linux-pci@vger.kernel.org,
	kvm@vger.kernel.org, loongson-kernel@lists.loongnix.cn
Subject: [PATCH v3 3/4] PCI/VGA: only deal with VGA class devices
Date: Thu,  8 Jun 2023 19:43:21 +0800	[thread overview]
Message-ID: <20230608114322.604887-4-15330273260@189.cn> (raw)
In-Reply-To: <20230608114322.604887-1-15330273260@189.cn>

From: Sui Jingfeng <suijingfeng@loongson.cn>

vgaarb only deal with the VGA devcie(pdev->class == 0x0300), so replace the
pci_get_subsys() function with pci_get_class(). Filter the non pci display
device out. There no need to process the non display PCI device.

Signed-off-by: Sui Jingfeng <suijingfeng@loongson.cn>
---
 drivers/pci/vgaarb.c | 22 ++++++++++++----------
 1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/drivers/pci/vgaarb.c b/drivers/pci/vgaarb.c
index 7f0347f4f6fd..b0bf4952a95d 100644
--- a/drivers/pci/vgaarb.c
+++ b/drivers/pci/vgaarb.c
@@ -756,10 +756,6 @@ static bool vga_arbiter_add_pci_device(struct pci_dev *pdev)
 	struct pci_dev *bridge;
 	u16 cmd;
 
-	/* Only deal with VGA class devices */
-	if ((pdev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
-		return false;
-
 	/* Allocate structure */
 	vgadev = kzalloc(sizeof(struct vga_device), GFP_KERNEL);
 	if (vgadev == NULL) {
@@ -1499,7 +1495,9 @@ static int pci_notify(struct notifier_block *nb, unsigned long action,
 	struct pci_dev *pdev = to_pci_dev(dev);
 	bool notify = false;
 
-	vgaarb_dbg(dev, "%s\n", __func__);
+	/* Only deal with VGA class devices */
+	if ((pdev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
+		return 0;
 
 	/* For now we're only intereted in devices added and removed. I didn't
 	 * test this thing here, so someone needs to double check for the
@@ -1509,6 +1507,8 @@ static int pci_notify(struct notifier_block *nb, unsigned long action,
 	else if (action == BUS_NOTIFY_DEL_DEVICE)
 		notify = vga_arbiter_del_pci_device(pdev);
 
+	vgaarb_dbg(dev, "%s: action = %lu\n", __func__, action);
+
 	if (notify)
 		vga_arbiter_notify_clients();
 	return 0;
@@ -1533,8 +1533,8 @@ static struct miscdevice vga_arb_device = {
 
 static int __init vga_arb_device_init(void)
 {
+	struct pci_dev *pdev = NULL;
 	int rc;
-	struct pci_dev *pdev;
 
 	rc = misc_register(&vga_arb_device);
 	if (rc < 0)
@@ -1545,11 +1545,13 @@ static int __init vga_arb_device_init(void)
 	/* We add all PCI devices satisfying VGA class in the arbiter by
 	 * default
 	 */
-	pdev = NULL;
-	while ((pdev =
-		pci_get_subsys(PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID,
-			       PCI_ANY_ID, pdev)) != NULL)
+	while (1) {
+		pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev);
+		if (!pdev)
+			break;
+
 		vga_arbiter_add_pci_device(pdev);
+	};
 
 	pr_info("loaded\n");
 	return rc;
-- 
2.25.1

