PCI: Skip attaching driver in device_add()
We want to add PCI devices to the device tree as early as possible but
delay attaching drivers.
device_add() adds a device to the device hierarchy and (via
device_attach()) attaches a matching driver and calls its .probe() method.
We want to separate adding the device to the hierarchy from attaching the
driver.
This patch does that by adding "match_driver" in struct pci_dev. When
false, we return failure from pci_bus_match(), which makes device_attach()
believe there's no matching driver.
Later, we set "match_driver = true" and call device_attach() again, which
now attaches the driver and calls its .probe() method.
[bhelgaas: changelog, explicitly init dev->match_driver,
fold device_attach() call into pci_bus_add_device()]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
index 847f3ca..c8709c6 100644
--- a/drivers/pci/bus.c
+++ b/drivers/pci/bus.c
@@ -177,10 +177,15 @@
if (retval)
return retval;
+ dev->match_driver = false;
retval = device_add(&dev->dev);
if (retval)
return retval;
+ dev->match_driver = true;
+ retval = device_attach(&dev->dev);
+ WARN_ON(retval < 0);
+
dev->is_added = 1;
pci_proc_attach_device(dev);
pci_create_sysfs_dev_files(dev);