[PATCH v3 2/2] hw/rtc/mc146818rtc: Convert to 3-phase reset (Resettable interface)

["Philippe Mathieu-Daudé" <f4bug@amsat.org>]

TYPE_MC146818_RTC is an ISA device, so its DeviceClass::reset()
handler is called automatically when its qbus parent is reset
(we don't need to register it manually).

We have 2 reset() methods: a generic one and the qdev one.
Merge them into a reset_enter handler (keeping the IRQ lowering
to a reset_hold one), and remove the qemu_register_reset() call.

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
---
 hw/rtc/mc146818rtc.c | 42 ++++++++++++++++++++++--------------------
 1 file changed, 22 insertions(+), 20 deletions(-)

diff --git a/hw/rtc/mc146818rtc.c b/hw/rtc/mc146818rtc.c
index 5d0fcacd0c0..836c3691706 100644
--- a/hw/rtc/mc146818rtc.c
+++ b/hw/rtc/mc146818rtc.c
@@ -872,22 +872,6 @@ static void rtc_notify_suspend(Notifier *notifier, void *data)
     rtc_set_memory(ISA_DEVICE(s), 0xF, 0xFE);
 }
 
-static void rtc_reset(void *opaque)
-{
-    RTCState *s = opaque;
-
-    s->cmos_data[RTC_REG_B] &= ~(REG_B_PIE | REG_B_AIE | REG_B_SQWE);
-    s->cmos_data[RTC_REG_C] &= ~(REG_C_UF | REG_C_IRQF | REG_C_PF | REG_C_AF);
-    check_update_timer(s);
-
-    qemu_irq_lower(s->irq);
-
-    if (s->lost_tick_policy == LOST_TICK_POLICY_SLEW) {
-        s->irq_coalesced = 0;
-        s->irq_reinject_on_ack_count = 0;
-    }
-}
-
 static const MemoryRegionOps cmos_ops = {
     .read = cmos_ioport_read,
     .write = cmos_ioport_write,
@@ -962,7 +946,6 @@ static void rtc_realizefn(DeviceState *dev, Error **errp)
     memory_region_add_coalescing(&s->coalesced_io, 0, 1);
 
     qdev_set_legacy_instance_id(dev, RTC_ISA_BASE, 3);
-    qemu_register_reset(rtc_reset, s);
 
     object_property_add_tm(OBJECT(s), "date", rtc_get_date);
 
@@ -998,15 +981,32 @@ static Property mc146818rtc_properties[] = {
     DEFINE_PROP_END_OF_LIST(),
 };
 
-static void rtc_resetdev(DeviceState *d)
+static void rtc_reset_enter(Object *obj, ResetType type)
 {
-    RTCState *s = MC146818_RTC(d);
+    RTCState *s = MC146818_RTC(obj);
 
     /* Reason: VM do suspend self will set 0xfe
      * Reset any values other than 0xfe(Guest suspend case) */
     if (s->cmos_data[0x0f] != 0xfe) {
         s->cmos_data[0x0f] = 0x00;
     }
+
+    s->cmos_data[RTC_REG_B] &= ~(REG_B_PIE | REG_B_AIE | REG_B_SQWE);
+    s->cmos_data[RTC_REG_C] &= ~(REG_C_UF | REG_C_IRQF | REG_C_PF | REG_C_AF);
+    check_update_timer(s);
+
+
+    if (s->lost_tick_policy == LOST_TICK_POLICY_SLEW) {
+        s->irq_coalesced = 0;
+        s->irq_reinject_on_ack_count = 0;
+    }
+}
+
+static void rtc_reset_hold(Object *obj)
+{
+    RTCState *s = MC146818_RTC(obj);
+
+    qemu_irq_lower(s->irq);
 }
 
 static void rtc_build_aml(ISADevice *isadev, Aml *scope)
@@ -1033,11 +1033,13 @@ static void rtc_build_aml(ISADevice *isadev, Aml *scope)
 static void rtc_class_initfn(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
+    ResettableClass *rc = RESETTABLE_CLASS(klass);
     ISADeviceClass *isa = ISA_DEVICE_CLASS(klass);
 
     dc->realize = rtc_realizefn;
-    dc->reset = rtc_resetdev;
     dc->vmsd = &vmstate_rtc;
+    rc->phases.enter = rtc_reset_enter;
+    rc->phases.hold = rtc_reset_hold;
     isa->build_aml = rtc_build_aml;
     device_class_set_props(dc, mc146818rtc_properties);
 }
-- 
2.26.3