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PCI: Put pci_dev in device tree as early as possible

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We want to put pci_dev structs in the device tree as soon as possible so
for_each_pci_dev() iteration will not miss them, but driver attachment
needs to be delayed until after pci_assign_unassigned_resources() to make
sure all devices have resources assigned first.

This patch moves device registering from pci_bus_add_devices() to
pci_device_add(), which happens earlier, leaving driver attachment in
pci_bus_add_devices().

It also removes unattached child bus handling in pci_bus_add_devices().
That's not needed because child bus via pci_add_new_bus() is already
in parent bus children list.

[bhelgaas: changelog]
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>
This commit is contained in:
Yinghai Lu
2013-01-21 13:20:52 -08:00
committed by Bjorn Helgaas
parent 58d9a38f6f
commit 4f535093cf
4 changed files with 41 additions and 82 deletions
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78
drivers/pci/bus.c
View File

@@ -161,73 +161,35 @@ pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
void __weak pcibios_resource_survey_bus(struct pci_bus *bus) { }
/**
* pci_bus_add_device - add a single device
* pci_bus_add_device - start driver for a single device
* @dev: device to add
*
* This adds a single pci device to the global
* device list and adds sysfs and procfs entries
* This adds add sysfs entries and start device drivers
*/
int pci_bus_add_device(struct pci_dev *dev)
{
int retval;
pci_fixup_device(pci_fixup_final, dev);
retval = pcibios_add_device(dev);
if (retval)
return retval;
dev->match_driver = false;
retval = device_add(&dev->dev);
if (retval)
return retval;
/*
* Can not put in pci_device_add yet because resources
* are not assigned yet for some devices.
*/
pci_create_sysfs_dev_files(dev);
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);
return 0;
}
/**
* pci_bus_add_child - add a child bus
* @bus: bus to add
*
* This adds sysfs entries for a single bus
*/
int pci_bus_add_child(struct pci_bus *bus)
{
int retval;
if (bus->bridge)
bus->dev.parent = bus->bridge;
retval = device_register(&bus->dev);
if (retval)
return retval;
bus->is_added = 1;
/* Create legacy_io and legacy_mem files for this bus */
pci_create_legacy_files(bus);
return retval;
}
/**
* pci_bus_add_devices - insert newly discovered PCI devices
* pci_bus_add_devices - start driver for PCI devices
* @bus: bus to check for new devices
*
* Add newly discovered PCI devices (which are on the bus->devices
* list) to the global PCI device list, add the sysfs and procfs
* entries. Where a bridge is found, add the discovered bus to
* the parents list of child buses, and recurse (breadth-first
* to be compatible with 2.4)
*
* Call hotplug for each new devices.
* Start driver for PCI devices and add some sysfs entries.
*/
void pci_bus_add_devices(const struct pci_bus *bus)
{
@@ -240,36 +202,20 @@ void pci_bus_add_devices(const struct pci_bus *bus)
if (dev->is_added)
continue;
retval = pci_bus_add_device(dev);
if (retval)
dev_err(&dev->dev, "Error adding device, continuing\n");
}
list_for_each_entry(dev, &bus->devices, bus_list) {
BUG_ON(!dev->is_added);
child = dev->subordinate;
/*
* If there is an unattached subordinate bus, attach
* it and then scan for unattached PCI devices.
*/
if (!child)
continue;
if (list_empty(&child->node)) {
down_write(&pci_bus_sem);
list_add_tail(&child->node, &dev->bus->children);
up_write(&pci_bus_sem);
}
pci_bus_add_devices(child);
/*
* register the bus with sysfs as the parent is now
* properly registered.
*/
if (child->is_added)
continue;
retval = pci_bus_add_child(child);
if (retval)
dev_err(&dev->dev, "Error adding bus, continuing\n");
child->is_added = 1;
}
}