This patch fix a bug in mac_via where it failed to actually realize devices it was using.
And move the init codes which inits the mos6522 objects and properties on them from realize()
into init(). However, we keep qdev_set_parent_bus in realize(), otherwise it will cause
device-introspect-test test fail. Then do the realize mos6522 device in the mac_vir_realize.

Signed-off-by: Pan Nengyuan <pannengyuan@huawei.com>
---
Cc: Laurent Vivier <laurent@vivier.eu>
Cc: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
---
v4->v3:
- split v3 into two patches, this patch fix incorrect creation of mos6522, move inits and props
  from realize into init.
v5->v4:
- remove redundant code.
- As discussion in https://patchwork.kernel.org/patch/11421229/, we still keep 
  qdev_set_parent_bus in realize().
---
 hw/misc/mac_via.c | 40 +++++++++++++++++++++++++++-------------
 1 file changed, 27 insertions(+), 13 deletions(-)

diff --git a/hw/misc/mac_via.c b/hw/misc/mac_via.c
index b7d0012794..d208f0b18a 100644
--- a/hw/misc/mac_via.c
+++ b/hw/misc/mac_via.c
@@ -868,24 +868,24 @@ static void mac_via_reset(DeviceState *dev)
 static void mac_via_realize(DeviceState *dev, Error **errp)
 {
     MacVIAState *m = MAC_VIA(dev);
-    MOS6522State *ms;
     struct tm tm;
     int ret;
+    Error *err = NULL;
 
-    /* Init VIAs 1 and 2 */
-    sysbus_init_child_obj(OBJECT(dev), "via1", &m->mos6522_via1,
-                          sizeof(m->mos6522_via1), TYPE_MOS6522_Q800_VIA1);
+    qdev_set_parent_bus(DEVICE(&m->mos6522_via1), sysbus_get_default());
+    qdev_set_parent_bus(DEVICE(&m->mos6522_via2), sysbus_get_default());
 
-    sysbus_init_child_obj(OBJECT(dev), "via2", &m->mos6522_via2,
-                          sizeof(m->mos6522_via2), TYPE_MOS6522_Q800_VIA2);
+    object_property_set_bool(OBJECT(&m->mos6522_via1), true, "realized", &err);
+    if (err != NULL) {
+        error_propagate(errp, err);
+        return;
+    }
 
-    /* Pass through mos6522 output IRQs */
-    ms = MOS6522(&m->mos6522_via1);
-    object_property_add_alias(OBJECT(dev), "irq[0]", OBJECT(ms),
-                              SYSBUS_DEVICE_GPIO_IRQ "[0]", &error_abort);
-    ms = MOS6522(&m->mos6522_via2);
-    object_property_add_alias(OBJECT(dev), "irq[1]", OBJECT(ms),
-                              SYSBUS_DEVICE_GPIO_IRQ "[0]", &error_abort);
+    object_property_set_bool(OBJECT(&m->mos6522_via2), true, "realized", &err);
+    if (err != NULL) {
+        error_propagate(errp, err);
+        return;
+    }
 
     /* Pass through mos6522 input IRQs */
     qdev_pass_gpios(DEVICE(&m->mos6522_via1), dev, "via1-irq");
@@ -948,6 +948,20 @@ static void mac_via_init(Object *obj)
     /* ADB */
     qbus_create_inplace((BusState *)&m->adb_bus, sizeof(m->adb_bus),
                         TYPE_ADB_BUS, DEVICE(obj), "adb.0");
+
+    /* Init VIAs 1 and 2 */
+    object_initialize_child(OBJECT(m), "via1", &m->mos6522_via1,
+                            sizeof(m->mos6522_via1), TYPE_MOS6522_Q800_VIA1,
+                            &error_abort, NULL);
+    object_initialize_child(OBJECT(m), "via2", &m->mos6522_via2,
+                            sizeof(m->mos6522_via2), TYPE_MOS6522_Q800_VIA2,
+                            &error_abort, NULL);
+
+    /* Pass through mos6522 output IRQs */
+    object_property_add_alias(OBJECT(m), "irq[0]", OBJECT(&m->mos6522_via1),
+                              SYSBUS_DEVICE_GPIO_IRQ "[0]", &error_abort);
+    object_property_add_alias(OBJECT(m), "irq[1]", OBJECT(&m->mos6522_via2),
+                              SYSBUS_DEVICE_GPIO_IRQ "[0]", &error_abort);
 }
 
 static void postload_update_cb(void *opaque, int running, RunState state)
-- 
2.18.2