path: root/drivers/acpi
diff options
authorAaron Lu <aaron.lu@intel.com>2013-06-04 23:02:58 +0200
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2013-06-05 13:11:47 +0200
commit9f29ab11ddbfc12db54df5a66dab22b39ad94e8e (patch)
tree86c265ebf4022c33601f49ecc7dd5b1176e74c7e /drivers/acpi
parenta98d4f64a20b2b88697e7e08c871144a7e3f0ec4 (diff)
ACPI / scan: do not match drivers against objects having scan handlers
With the introduction of ACPI scan handlers, an ACPI device object with an ACPI scan handler attached to it must not be bound to an ACPI driver any more. Therefore it doesn't make sense to match those ACPI device objects against a newly registered ACPI driver in acpi_bus_match(), so make that function return 0 if the device object passed to it has an ACPI scan handler attached. This also addresses a regression related to a broken ACPI table in the BIOS, where it has defined a _ROM method under the PCI root bridge object. This causes the video module to treat that object as a display controller device (since only display devices are supposed to have a _ROM method defined according to the ACPI spec). As a result, the ACPI video driver binds to the PCI root bridge object and overwrites the previously assigned driver_data field of it, causing subsequent calls to acpi_get_pci_dev() to fail. [rjw: Subject and changelog] References: https://bugzilla.kernel.org/show_bug.cgi?id=58091 Reported-by: Jason Cassell <bluesloth600@gmail.com> Reported-and-bisected-by: Dmitry S. Demin <dmitryy.demin@gmail.com> Cc: 3.9+ <stable@kernel.org> Signed-off-by: Aaron Lu <aaron.lu@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/acpi')
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 44225cb15f3..90c5759e135 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -740,6 +740,10 @@ static int acpi_bus_match(struct device *dev, struct device_driver *drv)
struct acpi_device *acpi_dev = to_acpi_device(dev);
struct acpi_driver *acpi_drv = to_acpi_driver(drv);
+ /* Skip ACPI device objects with scan handlers attached. */
+ if (acpi_dev->handler)
+ return 0;
return acpi_dev->flags.match_driver
&& !acpi_match_device_ids(acpi_dev, acpi_drv->ids);