[Qemu-devel] [PATCH v3 2/3] qdev: interface for SysBusDevice to change property on requirement

[Liu Ping Fan <qemulist@gmail.com>]

qdev's property can not be set after realized, but there is a
requirement of adjusting device's behavior on different mother
boards.  So introducing a callback in sysbus_try_create_simple()
to adjust device's property on board's demand.

(This patch is needed by the later one which changes hpet's intcap
property)

Signed-off-by: Liu Ping Fan <pingfank@linux.vnet.ibm.com>
---
 hw/core/sysbus.c    | 5 ++++-
 hw/i386/pc.c        | 2 +-
 include/hw/sysbus.h | 8 +++++---
 3 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/hw/core/sysbus.c b/hw/core/sysbus.c
index 9004d8c..e894bbb 100644
--- a/hw/core/sysbus.c
+++ b/hw/core/sysbus.c
@@ -172,7 +172,7 @@ DeviceState *sysbus_create_varargs(const char *name,
     return dev;
 }
 
-DeviceState *sysbus_try_create_varargs(const char *name,
+DeviceState *sysbus_try_create_varargs(const char *name, CompatSet set,
                                        hwaddr addr, ...)
 {
     DeviceState *dev;
@@ -185,6 +185,9 @@ DeviceState *sysbus_try_create_varargs(const char *name,
     if (!dev) {
         return NULL;
     }
+    if (set) {
+        set(dev);
+    }
     s = SYS_BUS_DEVICE(dev);
     qdev_init_nofail(dev);
     if (addr != (hwaddr)-1) {
diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index e8bc8ce..09c10ac 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -1247,7 +1247,7 @@ void pc_basic_device_init(ISABus *isa_bus, qemu_irq *gsi,
      * when the HPET wants to take over. Thus we have to disable the latter.
      */
     if (!no_hpet && (!kvm_irqchip_in_kernel() || kvm_has_pit_state2())) {
-        hpet = sysbus_try_create_simple("hpet", HPET_BASE, NULL);
+        hpet = sysbus_try_create_simple("hpet", NULL, HPET_BASE, NULL);
 
         if (hpet) {
             for (i = 0; i < GSI_NUM_PINS; i++) {
diff --git a/include/hw/sysbus.h b/include/hw/sysbus.h
index bb50a87..47337f2 100644
--- a/include/hw/sysbus.h
+++ b/include/hw/sysbus.h
@@ -58,6 +58,8 @@ struct SysBusDevice {
     pio_addr_t pio[QDEV_MAX_PIO];
 };
 
+typedef void (*CompatSet)(DeviceState *dev);
+
 void sysbus_init_mmio(SysBusDevice *dev, MemoryRegion *memory);
 MemoryRegion *sysbus_mmio_get_region(SysBusDevice *dev, int n);
 void sysbus_init_irq(SysBusDevice *dev, qemu_irq *p);
@@ -77,7 +79,7 @@ MemoryRegion *sysbus_address_space(SysBusDevice *dev);
 /* Legacy helper function for creating devices.  */
 DeviceState *sysbus_create_varargs(const char *name,
                                  hwaddr addr, ...);
-DeviceState *sysbus_try_create_varargs(const char *name,
+DeviceState *sysbus_try_create_varargs(const char *name, CompatSet set,
                                        hwaddr addr, ...);
 static inline DeviceState *sysbus_create_simple(const char *name,
                                               hwaddr addr,
@@ -86,11 +88,11 @@ static inline DeviceState *sysbus_create_simple(const char *name,
     return sysbus_create_varargs(name, addr, irq, NULL);
 }
 
-static inline DeviceState *sysbus_try_create_simple(const char *name,
+static inline DeviceState *sysbus_try_create_simple(const char *name, CompatSet set,
                                                     hwaddr addr,
                                                     qemu_irq irq)
 {
-    return sysbus_try_create_varargs(name, addr, irq, NULL);
+    return sysbus_try_create_varargs(name, set, addr, irq, NULL);
 }
 
 #endif /* !HW_SYSBUS_H */
-- 
1.8.1.4