ACPI: simplify acpi_pci_irq_add_prt() API

A PCI domain cannot change as you descend down subordinate buses, which
makes the 'segment' argument to acpi_pci_irq_add_prt() useless.

Change the interface to take a struct pci_bus *, from whence we can derive
the bus number and segment. Reducing the number of arguments makes life
simpler for callers.

Signed-off-by: Alex Chiang <achiang@hp.com>
Acked-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/pci_irq.c b/drivers/acpi/pci_irq.c
index 51b9f82..3ed944c 100644
--- a/drivers/acpi/pci_irq.c
+++ b/drivers/acpi/pci_irq.c
@@ -182,7 +182,7 @@
 	}
 }
 
-static int acpi_pci_irq_add_entry(acpi_handle handle, int segment, int bus,
+static int acpi_pci_irq_add_entry(acpi_handle handle, struct pci_bus *bus,
 				  struct acpi_pci_routing_table *prt)
 {
 	struct acpi_prt_entry *entry;
@@ -196,8 +196,8 @@
 	 * 1=INTA, 2=INTB.  We use the PCI encoding throughout, so convert
 	 * it here.
 	 */
-	entry->id.segment = segment;
-	entry->id.bus = bus;
+	entry->id.segment = pci_domain_nr(bus);
+	entry->id.bus = bus->number;
 	entry->id.device = (prt->address >> 16) & 0xFFFF;
 	entry->pin = prt->pin + 1;
 
@@ -242,7 +242,7 @@
 	return 0;
 }
 
-int acpi_pci_irq_add_prt(acpi_handle handle, int segment, int bus)
+int acpi_pci_irq_add_prt(acpi_handle handle, struct pci_bus *bus)
 {
 	acpi_status status;
 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
@@ -271,7 +271,7 @@
 
 	entry = buffer.pointer;
 	while (entry && (entry->length > 0)) {
-		acpi_pci_irq_add_entry(handle, segment, bus, entry);
+		acpi_pci_irq_add_entry(handle, bus, entry);
 		entry = (struct acpi_pci_routing_table *)
 		    ((unsigned long)entry + entry->length);
 	}