diff --git a/hw/input/ps2.c b/hw/input/ps2.c
index 62ea4c228b..eae7df2096 100644
--- a/hw/input/ps2.c
+++ b/hw/input/ps2.c
@@ -1244,6 +1244,11 @@ static QemuInputHandler ps2_mouse_handler = {
     .sync  = ps2_mouse_sync,
 };
 
+static void ps2_mouse_realize(DeviceState *dev, Error **errp)
+{
+    qemu_input_handler_register(dev, &ps2_mouse_handler);
+}
+
 void *ps2_mouse_init(void (*update_irq)(void *, int), void *update_arg)
 {
     DeviceState *dev;
@@ -1259,8 +1264,6 @@ void *ps2_mouse_init(void (*update_irq)(void *, int), void *update_arg)
     ps2->update_irq = update_irq;
     ps2->update_arg = update_arg;
     vmstate_register(NULL, 0, &vmstate_ps2_mouse, s);
-    qemu_input_handler_register((DeviceState *)s,
-                                &ps2_mouse_handler);
     return s;
 }
 
@@ -1285,6 +1288,7 @@ static void ps2_mouse_class_init(ObjectClass *klass, void *data)
     DeviceClass *dc = DEVICE_CLASS(klass);
     PS2DeviceClass *ps2dc = PS2_DEVICE_CLASS(klass);
 
+    dc->realize = ps2_mouse_realize;
     device_class_set_parent_reset(dc, ps2_mouse_reset,
                                   &ps2dc->parent_reset);
 }