From: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
a37c0f48950b ("vgaarb: Select a default VGA device even if there's no
legacy VGA") extended the vga_arb_device_init() subsys_initcall so that if
there are no other eligible devices, it could select a disabled VGA device
as the default.
Move this detection from vga_arb_select_default_device() to
vga_arbiter_add_pci_device() so every device, even those hot-added or
enumerated after vga_arb_device_init() is eligible for selection as the
default VGA device.
Link: https://lore.kernel.org/r/20211015061512.2941859-5-chenhuacai@xxxxxxxxxxx
Based-on-patch-by: Huacai Chen <chenhuacai@xxxxxxxxxx>
Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Cc: Daniel Axtens <dja@xxxxxxxxxx>
Cc: Zhou Wang <wangzhou1@xxxxxxxxxxxxx>
---
drivers/gpu/vga/vgaarb.c | 27 +++++++++------------------
1 file changed, 9 insertions(+), 18 deletions(-)
diff --git a/drivers/gpu/vga/vgaarb.c b/drivers/gpu/vga/vgaarb.c
index 123b81628061..ad548917e602 100644
--- a/drivers/gpu/vga/vgaarb.c
+++ b/drivers/gpu/vga/vgaarb.c
@@ -656,7 +656,8 @@ static bool vga_is_boot_device(struct vga_device *vgadev)
* We use the first one we find, so if we've already found one,
* vgadev is no better.
*/
- if (boot_vga)
+ if (boot_vga &&
+ (boot_vga->owns & VGA_RSRC_LEGACY_MASK) == VGA_RSRC_LEGACY_MASK)
return false;
if ((vgadev->owns & VGA_RSRC_LEGACY_MASK) == VGA_RSRC_LEGACY_MASK)
@@ -693,6 +694,13 @@ static bool vga_is_boot_device(struct vga_device *vgadev)
return true;
}
+ /*
+ * vgadev has neither IO nor MEM enabled. If we haven't found any
+ * other VGA devices, it is the best candidate so far.
+ */
+ if (!boot_vga)
+ return true;
+
return false;
}
@@ -1559,21 +1567,6 @@ static struct miscdevice vga_arb_device = {
MISC_DYNAMIC_MINOR, "vga_arbiter", &vga_arb_device_fops
};
-static void __init vga_arb_select_default_device(void)
-{
- struct vga_device *vgadev;
-
- if (!vga_default_device()) {
- vgadev = list_first_entry_or_null(&vga_list,
- struct vga_device, list);
- if (vgadev) {
- struct device *dev = &vgadev->pdev->dev;
- vgaarb_info(dev, "setting as boot device (VGA legacy resources not available)\n");
- vga_set_default_device(vgadev->pdev);
- }
- }
-}
-
static int __init vga_arb_device_init(void)
{
int rc;
@@ -1603,8 +1596,6 @@ static int __init vga_arb_device_init(void)
vgaarb_info(dev, "no bridge control possible\n");
}
- vga_arb_select_default_device();
-
pr_info("loaded\n");
return rc;
}
--
2.25.1
