PCI hotplug: introduce functions for ACPI slot detection

Some ACPI related PCI hotplug code can be shared among PCI hotplug
drivers. This patch introduces the following functions in
drivers/pci/hotplug/acpi_pcihp.c to share the code, and changes
acpiphp and pciehp to use them.

- int acpi_pci_detect_ejectable(struct pci_bus *pbus)
  This checks if the specified PCI bus has ejectable slots.

- int acpi_pci_check_ejectable(struct pci_bus *pbus, acpi_handle handle)
  This checks if the specified handle is ejectable ACPI PCI slot. The
  'pbus' parameter is needed to check if 'handle' is PCI related ACPI
  object.

This patch also introduces the following inline function in
include/linux/pci-acpi.h, which is useful to get ACPI handle of the
PCI bridge from struct pci_bus of the bridge's secondary bus.

- static inline acpi_handle acpi_pci_get_bridge_handle(struct pci_bus *pbus)
  This returns ACPI handle of the PCI bridge which generates PCI bus
  specified by 'pbus'.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

2 files changed, 11 insertions, 0 deletions

diff --git a/include/linux/pci-acpi.h b/include/linux/pci-acpi.h
index 871e096e0fbc..042c166f65d5 100644
--- a/include/linux/pci-acpi.h
+++ b/include/linux/pci-acpi.h
@@ -60,6 +60,15 @@ static inline acpi_handle acpi_find_root_bridge_handle(struct pci_dev *pdev)
         return acpi_get_pci_rootbridge_handle(pci_domain_nr(pdev->bus),
                         pdev->bus->number);
 }
+
+static inline acpi_handle acpi_pci_get_bridge_handle(struct pci_bus *pbus)
+{
+        int seg = pci_domain_nr(pbus), busnr = pbus->number;
+        struct pci_dev *bridge = pbus->self;
+        if (bridge)
+                return DEVICE_ACPI_HANDLE(&(bridge->dev));
+        return acpi_get_pci_rootbridge_handle(seg, busnr);
+}
 #else
 #if !defined(AE_ERROR)
 typedef u32             acpi_status;
diff --git a/include/linux/pci_hotplug.h b/include/linux/pci_hotplug.h
index a00bd1a0f156..f7cc204fab07 100644
--- a/include/linux/pci_hotplug.h
+++ b/include/linux/pci_hotplug.h
@@ -228,6 +228,8 @@ extern acpi_status acpi_get_hp_params_from_firmware(struct pci_bus *bus,
                                 struct hotplug_params *hpp);
 int acpi_get_hp_hw_control_from_firmware(struct pci_dev *dev, u32 flags);
 int acpi_root_bridge(acpi_handle handle);
+int acpi_pci_check_ejectable(struct pci_bus *pbus, acpi_handle handle);
+int acpi_pci_detect_ejectable(struct pci_bus *pbus);
 #endif
 #endif