diff --git a/hw/misc/mos6522.c b/hw/misc/mos6522.c
index 8d5b419825..14cff26c61 100644
--- a/hw/misc/mos6522.c
+++ b/hw/misc/mos6522.c
@@ -463,6 +463,7 @@ static void mos6522_class_init(ObjectClass *oc, void *data)
     mdc->set_sr_int = mos6522_set_sr_int;
     mdc->portB_write = mos6522_portB_write;
     mdc->portA_write = mos6522_portA_write;
+    mdc->update_irq = mos6522_update_irq;
     mdc->get_timer1_counter_value = mos6522_get_counter_value;
     mdc->get_timer2_counter_value = mos6522_get_counter_value;
     mdc->get_timer1_load_time = mos6522_get_load_time;
diff --git a/include/hw/misc/mos6522.h b/include/hw/misc/mos6522.h
index f52b41920b..03d9f0c059 100644
--- a/include/hw/misc/mos6522.h
+++ b/include/hw/misc/mos6522.h
@@ -134,6 +134,7 @@ typedef struct MOS6522DeviceClass {
     void (*set_sr_int)(MOS6522State *dev);
     void (*portB_write)(MOS6522State *dev);
     void (*portA_write)(MOS6522State *dev);
+    void (*update_irq)(MOS6522State *dev);
     /* These are used to influence the CUDA MacOS timebase calibration */
     uint64_t (*get_timer1_counter_value)(MOS6522State *dev, MOS6522Timer *ti);
     uint64_t (*get_timer2_counter_value)(MOS6522State *dev, MOS6522Timer *ti);