diff --git a/hw/adb.h b/hw/adb.h
index 2fe981f..721f1ac 100644
--- a/hw/adb.h
+++ b/hw/adb.h
@@ -84,5 +84,4 @@ int adb_poll(ADBBusState *s, uint8_t *buf_out);
 #define TYPE_ADB_KEYBOARD "adb-keyboard"
 #define TYPE_ADB_MOUSE "adb-mouse"
 
-extern ADBBusState adb_bus;
 #endif /* !defined(__ADB_H__) */
diff --git a/hw/cuda.c b/hw/cuda.c
index b3a875c..b36c535 100644
--- a/hw/cuda.c
+++ b/hw/cuda.c
@@ -108,8 +108,6 @@
 /* CUDA returns time_t's offset from Jan 1, 1904, not 1970 */
 #define RTC_OFFSET                      2082844800
 
-ADBBusState adb_bus;
-
 static void cuda_update(CUDAState *s);
 static void cuda_receive_packet_from_host(CUDAState *s,
                                           const uint8_t *data, int len);
@@ -459,7 +457,7 @@ static void cuda_adb_poll(void *opaque)
     uint8_t obuf[ADB_MAX_OUT_LEN + 2];
     int olen;
 
-    olen = adb_poll(&adb_bus, obuf + 2);
+    olen = adb_poll(&s->adb_bus, obuf + 2);
     if (olen > 0) {
         obuf[0] = ADB_PACKET;
         obuf[1] = 0x40; /* polled data */
@@ -555,7 +553,7 @@ static void cuda_receive_packet_from_host(CUDAState *s,
         {
             uint8_t obuf[ADB_MAX_OUT_LEN + 2];
             int olen;
-            olen = adb_request(&adb_bus, obuf + 2, data + 1, len - 1);
+            olen = adb_request(&s->adb_bus, obuf + 2, data + 1, len - 1);
             if (olen > 0) {
                 obuf[0] = ADB_PACKET;
                 obuf[1] = 0x00;
@@ -713,7 +711,7 @@ static void cuda_initfn(Object *obj)
         s->timers[i].index = i;
     }
 
-    qbus_create_inplace((BusState *)&adb_bus, TYPE_ADB_BUS, DEVICE(obj),
+    qbus_create_inplace((BusState *)&s->adb_bus, TYPE_ADB_BUS, DEVICE(obj),
                         "adb.0");
 }
 
diff --git a/hw/ppc/mac.h b/hw/ppc/mac.h
index 26cb497..b17107b 100644
--- a/hw/ppc/mac.h
+++ b/hw/ppc/mac.h
@@ -28,6 +28,7 @@
 #include "exec/memory.h"
 #include "hw/sysbus.h"
 #include "hw/ide/internal.h"
+#include "hw/adb.h"
 
 /* SMP is not enabled, for now */
 #define MAX_CPUS 1
@@ -93,6 +94,7 @@ typedef struct CUDAState {
     uint8_t ier;
     uint8_t anh;
 
+    ADBBusState adb_bus;
     CUDATimer timers[2];
 
     uint32_t tick_offset;
diff --git a/hw/ppc/mac_newworld.c b/hw/ppc/mac_newworld.c
index 2892b36..6de810b 100644
--- a/hw/ppc/mac_newworld.c
+++ b/hw/ppc/mac_newworld.c
@@ -149,6 +149,7 @@ static void ppc_core99_init(QEMUMachineInitArgs *args)
     PCIBus *pci_bus;
     PCIDevice *macio;
     MACIOIDEState *macio_ide;
+    BusState *adb_bus;
     MacIONVRAMState *nvr;
     int bios_size;
     MemoryRegion *pic_mem, *escc_mem;
@@ -381,9 +382,11 @@ static void ppc_core99_init(QEMUMachineInitArgs *args)
                                                         "ide[1]"));
     macio_ide_init_drives(macio_ide, &hd[MAX_IDE_DEVS]);
 
-    dev = qdev_create(BUS(&adb_bus), TYPE_ADB_KEYBOARD);
+    dev = DEVICE(object_resolve_path_component(OBJECT(macio), "cuda"));
+    adb_bus = qdev_get_child_bus(dev, "adb.0");
+    dev = qdev_create(adb_bus, TYPE_ADB_KEYBOARD);
     qdev_init_nofail(dev);
-    dev = qdev_create(BUS(&adb_bus), TYPE_ADB_MOUSE);
+    dev = qdev_create(adb_bus, TYPE_ADB_MOUSE);
     qdev_init_nofail(dev);
 
     if (usb_enabled(machine_arch == ARCH_MAC99_U3)) {
diff --git a/hw/ppc/mac_oldworld.c b/hw/ppc/mac_oldworld.c
index 59b7199..9ed303a 100644
--- a/hw/ppc/mac_oldworld.c
+++ b/hw/ppc/mac_oldworld.c
@@ -92,6 +92,7 @@ static void ppc_heathrow_init(QEMUMachineInitArgs *args)
     PCIDevice *macio;
     MACIOIDEState *macio_ide;
     DeviceState *dev;
+    BusState *adb_bus;
     int bios_size;
     MemoryRegion *pic_mem;
     MemoryRegion *escc_mem, *escc_bar = g_new(MemoryRegion, 1);
@@ -281,9 +282,11 @@ static void ppc_heathrow_init(QEMUMachineInitArgs *args)
     hd[3] = hd[2] = NULL;
     pci_cmd646_ide_init(pci_bus, hd, 0);
 
-    dev = qdev_create(BUS(&adb_bus), TYPE_ADB_KEYBOARD);
+    dev = DEVICE(object_resolve_path_component(OBJECT(macio), "cuda"));
+    adb_bus = qdev_get_child_bus(dev, "adb.0");
+    dev = qdev_create(adb_bus, TYPE_ADB_KEYBOARD);
     qdev_init_nofail(dev);
-    dev = qdev_create(BUS(&adb_bus), TYPE_ADB_MOUSE);
+    dev = qdev_create(adb_bus, TYPE_ADB_MOUSE);
     qdev_init_nofail(dev);
 
     if (usb_enabled(false)) {
