PCI ACPI: Added a function to register _OSC with only PCIe devices.

The function pci_osc_support_set() traverses every root bridge when
checking for _OSC support for a capability.  It quits as soon as it finds a
device/bridge that doesn't support the requested capability. This won't
work for systems that have mixed PCI and PCIe bridges when checking for
PCIe features.  I split this function into two -- pci_osc_support_set() and
pcie_osc_support_set(). The latter is used when only PCIe devices should be
traversed.

Signed-off-by: Andrew Patterson <andrew.patterson@hp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/pci/pci-acpi.c

@@ -156,13 +156,13 @@ run_osc_out:
 }
 
 /**
- * pci_osc_support_set - register OS support to Firmware
+ * __pci_osc_support_set - register OS support to Firmware
  * @flags: OS support bits
  *
  * Update OS support fields and doing a _OSC Query to obtain an update
  * from Firmware on supported control bits.
  **/
-acpi_status pci_osc_support_set(u32 flags)
+acpi_status __pci_osc_support_set(u32 flags, const char *hid)
 {
 	u32 temp;
 	acpi_status retval;
@@ -176,7 +176,7 @@ acpi_status pci_osc_support_set(u32 flags)
 	temp = ctrlset_buf[OSC_CONTROL_TYPE];
 	ctrlset_buf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
 	ctrlset_buf[OSC_CONTROL_TYPE] = OSC_CONTROL_MASKS;
-	acpi_get_devices ( PCI_ROOT_HID_STRING,
+	acpi_get_devices(hid,
 			acpi_query_osc,
 			ctrlset_buf,
 			(void **) &retval );

include/linux/pci-acpi.h

@@ -48,7 +48,15 @@
 
 #ifdef CONFIG_ACPI
 extern acpi_status pci_osc_control_set(acpi_handle handle, u32 flags);
-extern acpi_status pci_osc_support_set(u32 flags);
+extern acpi_status __pci_osc_support_set(u32 flags, const char *hid);
+static inline acpi_status pci_osc_support_set(u32 flags)
+{
+	return __pci_osc_support_set(flags, PCI_ROOT_HID_STRING);
+}
+static inline acpi_status pcie_osc_support_set(u32 flags)
+{
+	return __pci_osc_support_set(flags, PCI_EXPRESS_ROOT_HID_STRING);
+}
 #else
 #if !defined(AE_ERROR)
 typedef u32 		acpi_status;
@@ -57,6 +65,7 @@ typedef u32 		acpi_status;
 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;}
 #endif
 
 #endif	/* _PCI_ACPI_H_ */