Commit 1e6ad870aa for qemu.org

commit 1e6ad870aa3941f33d4dbd34e778b77597bcbf0b
Author: Emmanuel Blot <emmanuel.blot@free.fr>
Date:   Thu Oct 15 11:27:53 2026 +0200

    hw/i2c: pca954x: migrate mux state

    The pca954x model had no VMStateDescription, so neither the channel
    selection nor the PCA9545 interrupt status survived a migration.

    This changes the migration stream of the pre-existing PCA9546 and
    PCA9548, which an older QEMU rejects.

    Reviewed-by: Cédric Le Goater <clg@redhat.com>
    Signed-off-by: Emmanuel Blot <emmanuel.blot@free.fr>
    Link: https://lore.kernel.org/qemu-devel/20261015-bmc-minerva-v3-6-7d50c8a108e5@free.fr
    Signed-off-by: Cédric Le Goater <clg@redhat.com>

diff --git a/hw/i2c/i2c_mux_pca954x.c b/hw/i2c/i2c_mux_pca954x.c
index 4bb078a03c..597e57d99a 100644
--- a/hw/i2c/i2c_mux_pca954x.c
+++ b/hw/i2c/i2c_mux_pca954x.c
@@ -28,6 +28,7 @@
 #include "hw/core/irq.h"
 #include "hw/core/qdev.h"
 #include "hw/core/qdev-properties.h"
+#include "migration/vmstate.h"
 #include "qemu/log.h"
 #include "qemu/queue.h"
 #include "qom/object.h"
@@ -270,6 +271,28 @@ static void pca954x_init(Object *obj)
     }
 }

+static int pca954x_post_load(void *opaque, int version_id)
+{
+    Pca954xState *s = PCA954X(opaque);
+
+    pca954x_enable_channel(s, s->control);
+    qemu_set_irq(s->int_out, s->int_status == 0);
+    return 0;
+}
+
+static const VMStateDescription vmstate_pca954x = {
+    .name = "pca954x",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .post_load = pca954x_post_load,
+    .fields = (const VMStateField[]) {
+        VMSTATE_SMBUS_DEVICE(parent, Pca954xState),
+        VMSTATE_UINT8(control, Pca954xState),
+        VMSTATE_UINT8(int_status, Pca954xState),
+        VMSTATE_END_OF_LIST()
+    },
+};
+
 static const Property pca954x_props[] = {
     DEFINE_PROP_STRING("name", Pca954xState, name),
 };
@@ -287,6 +310,7 @@ static void pca954x_class_init(ObjectClass *klass, const void *data)

     dc->desc = "Pca954x i2c-mux";
     dc->realize = pca954x_realize;
+    dc->vmsd = &vmstate_pca954x;

     k->write_data = pca954x_write_data;
     k->receive_byte = pca954x_read_byte;