diff options
Diffstat (limited to 'drivers/acpi/glue.c')
-rw-r--r-- | drivers/acpi/glue.c | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/drivers/acpi/glue.c b/drivers/acpi/glue.c index 24649ada08df..adec3d15810a 100644 --- a/drivers/acpi/glue.c +++ b/drivers/acpi/glue.c @@ -140,6 +140,46 @@ struct device *acpi_get_physical_device(acpi_handle handle) EXPORT_SYMBOL(acpi_get_physical_device); +/* ToDo: When a PCI bridge is found, return the PCI device behind the bridge + * This should work in general, but did not on a Lenovo T61 for the + * graphics card. But this must be fixed when the PCI device is + * bound and the kernel device struct is attached to the acpi device + * Note: A success call will increase reference count by one + * Do call put_device(dev) on the returned device then + */ +struct device *acpi_get_physical_pci_device(acpi_handle handle) +{ + struct device *dev; + long long device_id; + acpi_status status; + + status = + acpi_evaluate_integer(handle, "_ADR", NULL, &device_id); + + if (ACPI_FAILURE(status)) + return NULL; + + /* We need to attempt to determine whether the _ADR refers to a + PCI device or not. There's no terribly good way to do this, + so the best we can hope for is to assume that there'll never + be a device in the host bridge */ + if (device_id >= 0x10000) { + /* It looks like a PCI device. Does it exist? */ + dev = acpi_get_physical_device(handle); + } else { + /* It doesn't look like a PCI device. Does its parent + exist? */ + acpi_handle phandle; + if (acpi_get_parent(handle, &phandle)) + return NULL; + dev = acpi_get_physical_device(phandle); + } + if (!dev) + return NULL; + return dev; +} +EXPORT_SYMBOL(acpi_get_physical_pci_device); + static int acpi_bind_one(struct device *dev, acpi_handle handle) { struct acpi_device *acpi_dev; |