diff --git a/hw/i386/kvm/i8254.c b/hw/i386/kvm/i8254.c
index c1f4094..36d2e21 100644
--- a/hw/i386/kvm/i8254.c
+++ b/hw/i386/kvm/i8254.c
@@ -33,10 +33,6 @@
 #define CALIBRATION_ROUNDS   3
 
 #define KVM_PIT(obj) OBJECT_CHECK(KVMPITState, (obj), TYPE_KVM_I8254)
-#define KVM_PIT_CLASS(class) \
-    OBJECT_CLASS_CHECK(KVMPITClass, (class), TYPE_KVM_I8254)
-#define KVM_PIT_GET_CLASS(obj) \
-    OBJECT_GET_CLASS(KVMPITClass, (obj), TYPE_KVM_I8254)
 
 typedef struct KVMPITState {
     PITCommonState parent_obj;
@@ -46,12 +42,6 @@ typedef struct KVMPITState {
     int64_t kernel_clock_offset;
 } KVMPITState;
 
-typedef struct KVMPITClass {
-    PITCommonClass parent_class;
-
-    DeviceRealize parent_realize;
-} KVMPITClass;
-
 static int64_t abs64(int64_t v)
 {
     return v < 0 ? -v : v;
@@ -250,7 +240,8 @@ static void kvm_pit_vm_state_change(void *opaque, int running,
 static void kvm_pit_realizefn(DeviceState *dev, Error **errp)
 {
     PITCommonState *pit = PIT_COMMON(dev);
-    KVMPITClass *kpc = KVM_PIT_GET_CLASS(dev);
+    DeviceClass *dc_parent =
+            DEVICE_CLASS(object_class_get_parent_by_name(TYPE_KVM_I8254));
     KVMPITState *s = KVM_PIT(pit);
     struct kvm_pit_config config = {
         .flags = 0,
@@ -294,7 +285,7 @@ static void kvm_pit_realizefn(DeviceState *dev, Error **errp)
 
     qemu_add_vm_change_state_handler(kvm_pit_vm_state_change, s);
 
-    kpc->parent_realize(dev, errp);
+    dc_parent->realize(dev, errp);
 }
 
 static Property kvm_pit_properties[] = {
@@ -306,11 +297,9 @@ static Property kvm_pit_properties[] = {
 
 static void kvm_pit_class_init(ObjectClass *klass, void *data)
 {
-    KVMPITClass *kpc = KVM_PIT_CLASS(klass);
     PITCommonClass *k = PIT_COMMON_CLASS(klass);
     DeviceClass *dc = DEVICE_CLASS(klass);
 
-    kpc->parent_realize = dc->realize;
     dc->realize = kvm_pit_realizefn;
     k->set_channel_gate = kvm_pit_set_gate;
     k->get_channel_info = kvm_pit_get_channel_info;
@@ -325,7 +314,6 @@ static const TypeInfo kvm_pit_info = {
     .parent        = TYPE_PIT_COMMON,
     .instance_size = sizeof(KVMPITState),
     .class_init = kvm_pit_class_init,
-    .class_size = sizeof(KVMPITClass),
 };
 
 static void kvm_pit_register(void)
diff --git a/hw/timer/i8254.c b/hw/timer/i8254.c
index cd52140..8db8b34 100644
--- a/hw/timer/i8254.c
+++ b/hw/timer/i8254.c
@@ -35,15 +35,6 @@
 #define RW_STATE_WORD0 3
 #define RW_STATE_WORD1 4
 
-#define PIT_CLASS(class) OBJECT_CLASS_CHECK(PITClass, (class), TYPE_I8254)
-#define PIT_GET_CLASS(obj) OBJECT_GET_CLASS(PITClass, (obj), TYPE_I8254)
-
-typedef struct PITClass {
-    PITCommonClass parent_class;
-
-    DeviceRealize parent_realize;
-} PITClass;
-
 static void pit_irq_timer_update(PITChannelState *s, int64_t current_time);
 
 static int pit_get_count(PITChannelState *s)
@@ -325,7 +316,8 @@ static void pit_post_load(PITCommonState *s)
 static void pit_realizefn(DeviceState *dev, Error **err)
 {
     PITCommonState *pit = PIT_COMMON(dev);
-    PITClass *pc = PIT_GET_CLASS(dev);
+    DeviceClass *dc_parent =
+            DEVICE_CLASS(object_class_get_parent_by_name(TYPE_I8254));
     PITChannelState *s;
 
     s = &pit->channels[0];
@@ -338,7 +330,7 @@ static void pit_realizefn(DeviceState *dev, Error **err)
 
     qdev_init_gpio_in(dev, pit_irq_control, 1);
 
-    pc->parent_realize(dev, err);
+    dc_parent->realize(dev, err);
 }
 
 static Property pit_properties[] = {
@@ -348,11 +340,9 @@ static Property pit_properties[] = {
 
 static void pit_class_initfn(ObjectClass *klass, void *data)
 {
-    PITClass *pc = PIT_CLASS(klass);
     PITCommonClass *k = PIT_COMMON_CLASS(klass);
     DeviceClass *dc = DEVICE_CLASS(klass);
 
-    pc->parent_realize = dc->realize;
     dc->realize = pit_realizefn;
     k->set_channel_gate = pit_set_channel_gate;
     k->get_channel_info = pit_get_channel_info_common;
@@ -366,7 +356,6 @@ static const TypeInfo pit_info = {
     .parent        = TYPE_PIT_COMMON,
     .instance_size = sizeof(PITCommonState),
     .class_init    = pit_class_initfn,
-    .class_size    = sizeof(PITClass),
 };
 
 static void pit_register_types(void)
