PCI: add acpi_find_root_bridge_handle

Consolidate finding of a root bridge and getting its handle to the one
inline function. It's cut & pasted on multiple places. Use this new
inline in those.

Cc: kristen.c.accardi@intel.com
Acked-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

drivers/pci/hotplug/acpi_pcihp.c

@@ -404,10 +404,7 @@ int acpi_get_hp_hw_control_from_firmware(struct pci_dev *dev, u32 flags)
 	 * OSHP within the scope of the hotplug controller and its parents,
 	 * upto the host bridge under which this controller exists.
 	 */
-	while (pdev->bus->self)
-		pdev = pdev->bus->self;
-	handle = acpi_get_pci_rootbridge_handle(pci_domain_nr(pdev->bus),
-			pdev->bus->number);
+	handle = acpi_find_root_bridge_handle(pdev);
 	if (handle) {
 		acpi_get_name(handle, ACPI_FULL_PATHNAME, &string);
 		dbg("Trying to get hotplug control for %s\n",

drivers/pci/pcie/aer/aerdrv_acpi.c

@@ -36,12 +36,7 @@ int aer_osc_setup(struct pcie_device *pciedev)
 	if (acpi_pci_disabled)
 		return -1;
 
-	/* Find root host bridge */
-	while (pdev->bus->self)
-		pdev = pdev->bus->self;
-	handle = acpi_get_pci_rootbridge_handle(
-		pci_domain_nr(pdev->bus), pdev->bus->number);
-
+	handle = acpi_find_root_bridge_handle(pdev);
 	if (handle) {
 		pcie_osc_support_set(OSC_EXT_PCI_CONFIG_SUPPORT);
 		status = pci_osc_control_set(handle,

include/linux/pci-acpi.h

@@ -57,6 +57,15 @@ static inline acpi_status pcie_osc_support_set(u32 flags)
 {
 	return __pci_osc_support_set(flags, PCI_EXPRESS_ROOT_HID_STRING);
 }
+static inline acpi_handle acpi_find_root_bridge_handle(struct pci_dev *pdev)
+{
+	/* Find root host bridge */
+	while (pdev->bus->self)
+		pdev = pdev->bus->self;
+
+	return acpi_get_pci_rootbridge_handle(pci_domain_nr(pdev->bus),
+			pdev->bus->number);
+}
 #else
 #if !defined(AE_ERROR)
 typedef u32 		acpi_status;
@@ -66,6 +75,8 @@ static inline acpi_status pci_osc_control_set(acpi_handle handle, u32 flags)
 {return AE_ERROR;}
 static inline acpi_status pci_osc_support_set(u32 flags) {return AE_ERROR;} 
 static inline acpi_status pcie_osc_support_set(u32 flags) {return AE_ERROR;}
+static inline acpi_handle acpi_find_root_bridge_handle(struct pci_dev *pdev)
+{ return NULL; }
 #endif
 
 #endif	/* _PCI_ACPI_H_ */