ACPI / PCI: Fold acpi_pci_root_start() into acpi_pci_root_add()

Move the code from the ACPI PCI root bridge's .start() callback
routine, acpi_pci_root_start(), directly into acpi_pci_root_add()
and drop acpi_pci_root_start().

It is safe to do that, because it is now always guaranteed that
when struct pci_dev objects are created, their companion struct
acpi_device objects are already present, so it is not necessary to
wait for them to be created before calling pci_bus_add_devices().

This change was previously proposed in a different form by
Yinghai Lu.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Toshi Kani <toshi.kani@hp.com>

1 files changed, 11 insertions, 21 deletions

diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
index a233fe93dfac..0e593a203ff8 100644
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -47,7 +47,6 @@ ACPI_MODULE_NAME("pci_root");
 #define ACPI_PCI_ROOT_DEVICE_NAME       "PCI Root Bridge"
 static int acpi_pci_root_add(struct acpi_device *device);
 static int acpi_pci_root_remove(struct acpi_device *device, int type);
-static int acpi_pci_root_start(struct acpi_device *device);
 
 #define ACPI_PCIE_REQ_SUPPORT (OSC_EXT_PCI_CONFIG_SUPPORT \
                                 | OSC_ACTIVE_STATE_PWR_SUPPORT \
@@ -67,7 +66,6 @@ static struct acpi_driver acpi_pci_root_driver = {
         .ops = {
                 .add = acpi_pci_root_add,
                 .remove = acpi_pci_root_remove,
-                .start = acpi_pci_root_start,
                 },
 };
 
@@ -453,6 +451,7 @@ static int acpi_pci_root_add(struct acpi_device *device)
         struct acpi_pci_root *root;
         acpi_handle handle;
         struct acpi_device *child;
+        struct acpi_pci_driver *driver;
         u32 flags, base_flags;
         bool is_osc_granted = false;
 
@@ -632,24 +631,6 @@ static int acpi_pci_root_add(struct acpi_device *device)
         if (device->wakeup.flags.run_wake)
                 device_set_run_wake(root->bus->bridge, true);
 
-        return 0;
-
-out_del_root:
-        mutex_lock(&acpi_pci_root_lock);
-        list_del(&root->node);
-        mutex_unlock(&acpi_pci_root_lock);
-
-        acpi_pci_irq_del_prt(root->segment, root->secondary.start);
-end:
-        kfree(root);
-        return result;
-}
-
-static int acpi_pci_root_start(struct acpi_device *device)
-{
-        struct acpi_pci_root *root = acpi_driver_data(device);
-        struct acpi_pci_driver *driver;
-
         if (system_state != SYSTEM_BOOTING)
                 pci_assign_unassigned_bus_resources(root->bus);
 
@@ -664,8 +645,17 @@ static int acpi_pci_root_start(struct acpi_device *device)
                 pci_enable_bridges(root->bus);
 
         pci_bus_add_devices(root->bus);
-
         return 0;
+
+out_del_root:
+        mutex_lock(&acpi_pci_root_lock);
+        list_del(&root->node);
+        mutex_unlock(&acpi_pci_root_lock);
+
+        acpi_pci_irq_del_prt(root->segment, root->secondary.start);
+end:
+        kfree(root);
+        return result;
 }
 
 static int acpi_pci_root_remove(struct acpi_device *device, int type)