When the kernel is being initialized, and some hardwares are not added
to system, there won't be acpi_device structs for these devices. But
acpi_is_root_bridge() depends on acpi_device struct. As a result, all
the not-added root bridge will not be judged as a root bridge in
find_root_bridges(). And further more, no handle_hotplug_event_root()
notifier will be installed for them.
This patch introduces a new api to find all root bridges in system by
getting HID directly from ACPI namespace, not depending on acpi_device
struct.
Signed-off-by: Tang Chen <tangchen@xxxxxxxxxxxxxx>
Signed-off-by: Liu Jiang <jiang.liu@xxxxxxxxxx>
---
drivers/acpi/pci_root.c | 19 +++++++++++--------
1 files changed, 11 insertions(+), 8 deletions(-)
diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
index 6151d83..582eb11 100644
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -129,20 +129,23 @@ EXPORT_SYMBOL_GPL(acpi_get_pci_rootbridge_handle);
* acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
* @handle - the ACPI CA node in question.
*
- * Note: we could make this API take a struct acpi_device * instead, but
- * for now, it's more convenient to operate on an acpi_handle.
+ * Note: If a device is not added to the system yet, there won't be an
+ * acpi_device struct for it. So do not get HID and CID from acpi_device,
+ * get them from ACPI namespace directly.
*/
int acpi_is_root_bridge(acpi_handle handle)
{
- int ret;
- struct acpi_device *device;
+ struct acpi_device_info *info;
+ acpi_status status;
- ret = acpi_bus_get_device(handle, &device);
- if (ret)
+ status = acpi_get_object_info(handle, &info);
+ if (ACPI_FAILURE(status)) {
+ printk(KERN_ERR PREFIX "%s: Error reading"
+ "device info\n", __func__);
return 0;
+ }
- ret = acpi_match_device_ids(device, root_device_ids);
- if (ret)
+ if (acpi_match_object_info_ids(info, root_device_ids))
return 0;
else
return 1;
--
1.7.1
--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
