diff --git a/hw/tpm/tpm_crb.c b/hw/tpm/tpm_crb.c
index 07c6868d8d..6144081d30 100644
--- a/hw/tpm/tpm_crb.c
+++ b/hw/tpm/tpm_crb.c
@@ -22,6 +22,7 @@
 #include "hw/qdev-properties.h"
 #include "hw/pci/pci_ids.h"
 #include "hw/acpi/tpm.h"
+#include "hw/isa/isa.h"
 #include "migration/vmstate.h"
 #include "sysemu/tpm_backend.h"
 #include "sysemu/tpm_util.h"
@@ -34,7 +35,7 @@
 #include "tpm_crb.h"
 
 struct CRBState {
-    DeviceState parent_obj;
+    ISADevice parent_obj;
 
     TPMCRBState state;
 };
@@ -43,49 +44,49 @@ typedef struct CRBState CRBState;
 DECLARE_INSTANCE_CHECKER(CRBState, CRB,
                          TYPE_TPM_CRB)
 
-static void tpm_crb_none_request_completed(TPMIf *ti, int ret)
+static void tpm_crb_isa_request_completed(TPMIf *ti, int ret)
 {
     CRBState *s = CRB(ti);
 
     tpm_crb_request_completed(&s->state, ret);
 }
 
-static enum TPMVersion tpm_crb_none_get_version(TPMIf *ti)
+static enum TPMVersion tpm_crb_isa_get_version(TPMIf *ti)
 {
     CRBState *s = CRB(ti);
 
     return tpm_crb_get_version(&s->state);
 }
 
-static int tpm_crb_none_pre_save(void *opaque)
+static int tpm_crb_isa_pre_save(void *opaque)
 {
     CRBState *s = opaque;
 
     return tpm_crb_pre_save(&s->state);
 }
 
-static const VMStateDescription vmstate_tpm_crb_none = {
+static const VMStateDescription vmstate_tpm_crb_isa = {
     .name = "tpm-crb",
-    .pre_save = tpm_crb_none_pre_save,
+    .pre_save = tpm_crb_isa_pre_save,
     .fields = (VMStateField[]) {
         VMSTATE_END_OF_LIST(),
     }
 };
 
-static Property tpm_crb_none_properties[] = {
+static Property tpm_crb_isa_properties[] = {
     DEFINE_PROP_TPMBE("tpmdev", CRBState, state.tpmbe),
     DEFINE_PROP_BOOL("ppi", CRBState, state.ppi_enabled, true),
     DEFINE_PROP_END_OF_LIST(),
 };
 
-static void tpm_crb_none_reset(void *dev)
+static void tpm_crb_isa_reset(void *dev)
 {
     CRBState *s = CRB(dev);
 
     return tpm_crb_reset(&s->state, TPM_CRB_ADDR_BASE);
 }
 
-static void tpm_crb_none_realize(DeviceState *dev, Error **errp)
+static void tpm_crb_isa_realize(DeviceState *dev, Error **errp)
 {
     CRBState *s = CRB(dev);
 
@@ -100,52 +101,51 @@ static void tpm_crb_none_realize(DeviceState *dev, Error **errp)
 
     tpm_crb_init_memory(OBJECT(s), &s->state, errp);
 
-    memory_region_add_subregion(get_system_memory(),
+    memory_region_add_subregion(isa_address_space(ISA_DEVICE(dev)),
         TPM_CRB_ADDR_BASE, &s->state.mmio);
 
     if (s->state.ppi_enabled) {
-        memory_region_add_subregion(get_system_memory(),
+        memory_region_add_subregion(isa_address_space(ISA_DEVICE(dev)),
             TPM_PPI_ADDR_BASE, &s->state.ppi.ram);
     }
 
     if (xen_enabled()) {
-        tpm_crb_none_reset(dev);
+        tpm_crb_isa_reset(dev);
     } else {
-        qemu_register_reset(tpm_crb_none_reset, dev);
+        qemu_register_reset(tpm_crb_isa_reset, dev);
     }
 }
 
-static void tpm_crb_none_class_init(ObjectClass *klass, void *data)
+static void tpm_crb_isa_class_init(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
     TPMIfClass *tc = TPM_IF_CLASS(klass);
 
-    dc->realize = tpm_crb_none_realize;
-    device_class_set_props(dc, tpm_crb_none_properties);
-    dc->vmsd  = &vmstate_tpm_crb_none;
+    dc->realize = tpm_crb_isa_realize;
+    device_class_set_props(dc, tpm_crb_isa_properties);
+    dc->vmsd  = &vmstate_tpm_crb_isa;
     dc->user_creatable = true;
     tc->model = TPM_MODEL_TPM_CRB;
-    tc->get_version = tpm_crb_none_get_version;
-    tc->request_completed = tpm_crb_none_request_completed;
+    tc->get_version = tpm_crb_isa_get_version;
+    tc->request_completed = tpm_crb_isa_request_completed;
 
     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
 }
 
-static const TypeInfo tpm_crb_none_info = {
+static const TypeInfo tpm_crb_isa_info = {
     .name = TYPE_TPM_CRB,
-    /* could be TYPE_SYS_BUS_DEVICE (or LPC etc) */
-    .parent = TYPE_DEVICE,
+    .parent = TYPE_ISA_DEVICE,
     .instance_size = sizeof(CRBState),
-    .class_init  = tpm_crb_none_class_init,
+    .class_init  = tpm_crb_isa_class_init,
     .interfaces = (InterfaceInfo[]) {
         { TYPE_TPM_IF },
         { }
     }
 };
 
-static void tpm_crb_none_register(void)
+static void tpm_crb_isa_register(void)
 {
-    type_register_static(&tpm_crb_none_info);
+    type_register_static(&tpm_crb_isa_info);
 }
 
-type_init(tpm_crb_none_register)
+type_init(tpm_crb_isa_register)
diff --git a/hw/tpm/Kconfig b/hw/tpm/Kconfig
index a46663288c..1fd73fe617 100644
--- a/hw/tpm/Kconfig
+++ b/hw/tpm/Kconfig
@@ -22,7 +22,7 @@ config TPM_TIS
 
 config TPM_CRB
     bool
-    depends on TPM && PC
+    depends on TPM && ISA_BUS
     select TPM_BACKEND
 
 config TPM_SPAPR
