PCI: Put pci_dev in device tree as early as possible

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>

1 files changed, 28 insertions, 7 deletions

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 48b35e15374d..281d90f19c7a 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -623,6 +623,7 @@ static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent,
 {
         struct pci_bus *child;
         int i;
+        int ret;
 
         /*
          * Allocate a new bus, and inherit stuff from the parent..
@@ -637,8 +638,7 @@ static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent,
         child->bus_flags = parent->bus_flags;
 
         /* initialize some portions of the bus device, but don't register it
-         * now as the parent is not properly set up yet.  This device will get
-         * registered later in pci_bus_add_devices()
+         * now as the parent is not properly set up yet.
          */
         child->dev.class = &pcibus_class;
         dev_set_name(&child->dev, "%04x:%02x", pci_domain_nr(child), busnr);
@@ -651,11 +651,14 @@ static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent,
         child->primary = parent->busn_res.start;
         child->busn_res.end = 0xff;
 
-        if (!bridge)
-                return child;
+        if (!bridge) {
+                child->dev.parent = parent->bridge;
+                goto add_dev;
+        }
 
         child->self = bridge;
         child->bridge = get_device(&bridge->dev);
+        child->dev.parent = child->bridge;
         pci_set_bus_of_node(child);
         pci_set_bus_speed(child);
 
@@ -666,6 +669,13 @@ static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent,
         }
         bridge->subordinate = child;
 
+add_dev:
+        ret = device_register(&child->dev);
+        WARN_ON(ret < 0);
+
+        /* Create legacy_io and legacy_mem files for this bus */
+        pci_create_legacy_files(child);
+
         return child;
 }
 
@@ -1296,6 +1306,8 @@ static void pci_init_capabilities(struct pci_dev *dev)
 
 void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
 {
+        int ret;
+
         device_initialize(&dev->dev);
         dev->dev.release = pci_release_dev;
 
@@ -1326,6 +1338,17 @@ void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
         down_write(&pci_bus_sem);
         list_add_tail(&dev->bus_list, &bus->devices);
         up_write(&pci_bus_sem);
+
+        pci_fixup_device(pci_fixup_final, dev);
+        ret = pcibios_add_device(dev);
+        WARN_ON(ret < 0);
+
+        /* Notifier could use PCI capabilities */
+        dev->match_driver = false;
+        ret = device_add(&dev->dev);
+        WARN_ON(ret < 0);
+
+        pci_proc_attach_device(dev);
 }
 
 struct pci_dev *__ref pci_scan_single_device(struct pci_bus *bus, int devfn)
@@ -1644,13 +1667,13 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
         char bus_addr[64];
         char *fmt;
 
-
         b = pci_alloc_bus();
         if (!b)
                 return NULL;
 
         b->sysdata = sysdata;
         b->ops = ops;
+        b->number = b->busn_res.start = bus;
         b2 = pci_find_bus(pci_domain_nr(b), bus);
         if (b2) {
                 /* If we already got to this bus through a different bridge, ignore it */
@@ -1685,8 +1708,6 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
         /* Create legacy_io and legacy_mem files for this bus */
         pci_create_legacy_files(b);
 
-        b->number = b->busn_res.start = bus;
-
         if (parent)
                 dev_info(parent, "PCI host bridge to bus %s\n", dev_name(&b->dev));
         else