serial-pci-multi: factor out multi_serial_get_port_count()

Common function to be reused in next patch.
Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>

hw/char/serial-pci-multi.c

@@ -77,33 +77,34 @@ static void multi_serial_irq_mux(void *opaque, int n, int level)
     pci_set_irq(&pci->dev, pending);
 }
 
+static size_t multi_serial_get_port_count(PCIDeviceClass *pc)
+{
+    switch (pc->device_id) {
+    case 0x0003:
+        return 2;
+    case 0x0004:
+        return 4;
+    }
+
+    g_assert_not_reached();
+}
+
+
 static void multi_serial_pci_realize(PCIDevice *dev, Error **errp)
 {
     PCIDeviceClass *pc = PCI_DEVICE_GET_CLASS(dev);
     PCIMultiSerialState *pci = DO_UPCAST(PCIMultiSerialState, dev, dev);
     SerialState *s;
     Error *err = NULL;
-    int i, nr_ports = 0;
-
-    switch (pc->device_id) {
-    case 0x0003:
-        nr_ports = 2;
-        break;
-    case 0x0004:
-        nr_ports = 4;
-        break;
-    }
-    assert(nr_ports > 0);
-    assert(nr_ports <= PCI_SERIAL_MAX_PORTS);
+    size_t i, nports = multi_serial_get_port_count(pc);
 
     pci->dev.config[PCI_CLASS_PROG] = pci->prog_if;
     pci->dev.config[PCI_INTERRUPT_PIN] = 0x01;
-    memory_region_init(&pci->iobar, OBJECT(pci), "multiserial", 8 * nr_ports);
+    memory_region_init(&pci->iobar, OBJECT(pci), "multiserial", 8 * nports);
     pci_register_bar(&pci->dev, 0, PCI_BASE_ADDRESS_SPACE_IO, &pci->iobar);
-    pci->irqs = qemu_allocate_irqs(multi_serial_irq_mux, pci,
-                                   nr_ports);
+    pci->irqs = qemu_allocate_irqs(multi_serial_irq_mux, pci, nports);
 
-    for (i = 0; i < nr_ports; i++) {
+    for (i = 0; i < nports; i++) {
         s = pci->state + i;
         s->baudbase = 115200;
         serial_realize_core(s, &err);
@@ -113,7 +114,7 @@ static void multi_serial_pci_realize(PCIDevice *dev, Error **errp)
             return;
         }
         s->irq = pci->irqs[i];
-        pci->name[i] = g_strdup_printf("uart #%d", i + 1);
+        pci->name[i] = g_strdup_printf("uart #%zu", i + 1);
         memory_region_init_io(&s->io, OBJECT(pci), &serial_io_ops, s,
                               pci->name[i], 8);
         memory_region_add_subregion(&pci->iobar, 8 * i, &s->io);