Re: [Qemu-devel] [PATCH v2 2/3] audio: use object link instead ofqdev property to pass wm8750 reference

[maozy]

Hi, Philippe

On 10/12/18 5:53 PM, Philippe Mathieu-Daudé wrote:
Hi Mao,
On 12/10/2018 10:30, Mao Zhongyi wrote:
According to qdev-properties.h, properties of pointer type should
be avoided, it seems a link type property is a good substitution.

Cc: Jan Kiszka <jan.kis...@web.de>
Cc: Peter Maydell <peter.mayd...@linaro.org>
Cc: Gerd Hoffmann <kra...@redhat.com>
To: qemu-...@nongnu.org

Signed-off-by: Mao Zhongyi <maozhon...@cmss.chinamobile.com>
---
  hw/arm/musicpal.c          |  3 ++-
  hw/audio/marvell_88w8618.c | 14 ++++++--------
  2 files changed, 8 insertions(+), 9 deletions(-)

diff --git a/hw/arm/musicpal.c b/hw/arm/musicpal.c
index 3dafb41b0b..ac266f9253 100644
--- a/hw/arm/musicpal.c
+++ b/hw/arm/musicpal.c
@@ -1695,7 +1695,8 @@ static void musicpal_init(MachineState *machine)
      wm8750_dev = i2c_create_slave(i2c, TYPE_WM8750, MP_WM_ADDR);
      dev = qdev_create(NULL, "mv88w8618_audio");
      s = SYS_BUS_DEVICE(dev);
-    qdev_prop_set_ptr(dev, TYPE_WM8750, wm8750_dev);
+    object_property_set_link(OBJECT(dev), OBJECT(wm8750_dev),
+                             TYPE_WM8750, NULL);
      qdev_init_nofail(dev);
      sysbus_mmio_map(s, 0, MP_AUDIO_BASE);
      sysbus_connect_irq(s, 0, pic[MP_AUDIO_IRQ]);
diff --git a/hw/audio/marvell_88w8618.c b/hw/audio/marvell_88w8618.c
index cf6ce6979b..baab4a3d53 100644
--- a/hw/audio/marvell_88w8618.c
+++ b/hw/audio/marvell_88w8618.c
@@ -15,6 +15,7 @@
  #include "hw/i2c/i2c.h"
  #include "hw/audio/wm8750.h"
  #include "audio/audio.h"
+#include "qapi/error.h"
  
  #define MP_AUDIO_SIZE           0x00001000
  
@@ -252,6 +253,11 @@ static void mv88w8618_audio_init(Object *obj)
      memory_region_init_io(&s->iomem, obj, &mv88w8618_audio_ops, s,
                            "audio", MP_AUDIO_SIZE);
      sysbus_init_mmio(dev, &s->iomem);
+
+    object_property_add_link(OBJECT(dev), "mv88w8618", TYPE_WM8750,
+                             (Object **) &s->wm,
+                             qdev_prop_allow_set_link_before_realize,
+                             0, &error_abort);
  }
  
  static void mv88w8618_audio_realize(DeviceState *dev, Error **errp)
@@ -279,11 +285,6 @@ static const VMStateDescription mv88w8618_audio_vmsd = {
      }
  };
  
-static Property mv88w8618_audio_properties[] = {
-    DEFINE_PROP_PTR(TYPE_WM8750, mv88w8618_audio_state, wm),
-    {/* end of list */},
-};
-
  static void mv88w8618_audio_class_init(ObjectClass *klass, void *data)
  {
      DeviceClass *dc = DEVICE_CLASS(klass);
@@ -291,9 +292,6 @@ static void mv88w8618_audio_class_init(ObjectClass *klass, 
void *data)
      dc->realize = mv88w8618_audio_realize;
      dc->reset = mv88w8618_audio_reset;
      dc->vmsd = &mv88w8618_audio_vmsd;
-    dc->props = mv88w8618_audio_properties;
-    /* Reason: pointer property "wm8750" */
-    dc->user_creatable = false;

Having a link property isn't it the same restriction?

This task can found in 
https://wiki.qemu.org/Contribute/BiteSizedTasks#Device_models

Convert qdev pointer properties (defined with DEFINE_PROP_PTR) to QOM 
links. Example: commit 873b4d3.

Thanks,
Mao


  }
  
  static const TypeInfo mv88w8618_audio_info = {