Commit 4e6c9184 authored by Huacai Chen's avatar Huacai Chen Committed by Bjorn Helgaas
Browse files

PCI/VGA: Log bridge control messages when adding devices 

Previously vga_arb_device_init() iterated through all VGA devices and
indicated whether legacy VGA routing to each could be controlled by an
upstream bridge.

But we determine that information in vga_arbiter_add_pci_device(), which we
call for every device, so we can log it there without iterating through the
VGA devices again.

Note that we call vga_arbiter_check_bridge_sharing() before adding the
device to vga_list, so we have to handle the very first device separately.

Link: https://lore.kernel.org/r/20220224224753.297579-10-helgaas@kernel.org


Signed-off-by: default avatarHuacai Chen <chenhuacai@loongson.cn>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
parent dc593fd4

drivers/pci/vgaarb.c

+8 −11
Original line number Diff line number Diff line
@@ -719,8 +719,10 @@ static void vga_arbiter_check_bridge_sharing(struct vga_device *vgadev) 


	vgadev->bridge_has_one_vga = true;



	if (list_empty(&vga_list))

	if (list_empty(&vga_list)) {

		vgaarb_info(&vgadev->pdev->dev, "bridge control possible\n");

		return;

	}



	/* okay iterate the new devices bridge hierarachy */

	new_bus = vgadev->pdev->bus;
@@ -759,6 +761,11 @@ static void vga_arbiter_check_bridge_sharing(struct vga_device *vgadev) 
		}

		new_bus = new_bus->parent;

	}



	if (vgadev->bridge_has_one_vga)

		vgaarb_info(&vgadev->pdev->dev, "bridge control possible\n");

	else

		vgaarb_info(&vgadev->pdev->dev, "no bridge control possible\n");

}



/*
@@ -1557,7 +1564,6 @@ static int __init vga_arb_device_init(void) 
{

	int rc;

	struct pci_dev *pdev;

	struct vga_device *vgadev;



	rc = misc_register(&vga_arb_device);

	if (rc < 0)
@@ -1573,15 +1579,6 @@ static int __init vga_arb_device_init(void) 
			       PCI_ANY_ID, pdev)) != NULL)

		vga_arbiter_add_pci_device(pdev);



	list_for_each_entry(vgadev, &vga_list, list) {

		struct device *dev = &vgadev->pdev->dev;



		if (vgadev->bridge_has_one_vga)

			vgaarb_info(dev, "bridge control possible\n");

		else

			vgaarb_info(dev, "no bridge control possible\n");

	}



	pr_info("loaded\n");

	return rc;

}