usb-ehci: add ehci unrealize funciton

cleanup ehci controller resource, both pci and sysbus
if they're necessary.
Signed-off-by: NGonglei <arei.gonglei@huawei.com>
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>

hw/usb/hcd-ehci.c

@@ -2471,6 +2471,31 @@ void usb_ehci_realize(EHCIState *s, DeviceState *dev, Error **errp)
     s->vmstate = qemu_add_vm_change_state_handler(usb_ehci_vm_state_change, s);
 }
 
+void usb_ehci_unrealize(EHCIState *s, DeviceState *dev, Error **errp)
+{
+    if (s->frame_timer) {
+        timer_del(s->frame_timer);
+        timer_free(s->frame_timer);
+        s->frame_timer = NULL;
+    }
+    if (s->async_bh) {
+        qemu_bh_delete(s->async_bh);
+    }
+
+    ehci_queues_rip_all(s, 0);
+    ehci_queues_rip_all(s, 1);
+
+    memory_region_del_subregion(&s->mem, &s->mem_caps);
+    memory_region_del_subregion(&s->mem, &s->mem_opreg);
+    memory_region_del_subregion(&s->mem, &s->mem_ports);
+
+    usb_bus_release(&s->bus);
+
+    if (s->vmstate) {
+        qemu_del_vm_change_state_handler(s->vmstate);
+    }
+}
+
 void usb_ehci_init(EHCIState *s, DeviceState *dev)
 {
     /* 2.2 host controller interface version */

hw/usb/hcd-ehci.h

@@ -323,6 +323,7 @@ extern const VMStateDescription vmstate_ehci;
 
 void usb_ehci_init(EHCIState *s, DeviceState *dev);
 void usb_ehci_realize(EHCIState *s, DeviceState *dev, Error **errp);
+void usb_ehci_unrealize(EHCIState *s, DeviceState *dev, Error **errp);
 
 #define TYPE_PCI_EHCI "pci-ehci-usb"
 #define PCI_EHCI(obj) OBJECT_CHECK(EHCIPCIState, (obj), TYPE_PCI_EHCI)