Commit 29a7f5da98 for qemu.org

commit 29a7f5da989328335815f53c8b291e052f183b13
Author: Marc-André Lureau <marcandre.lureau@redhat.com>
Date:   Sat Jan 17 01:05:29 2026 +0400

    audio: move pcm_ops into AudioMixengBackendClass

    Remove the separate audio_pcm_ops structure and move its function
    pointers directly into AudioMixengBackendClass. This is a cleaner
    QOM-style design where the PCM operations are part of the class
    vtable rather than a separate indirection through hw->pcm_ops.

    The HWVoiceOut and HWVoiceIn structures no longer need to store
    a pcm_ops pointer, as the operations are now accessed through
    the class with AUDIO_MIXENG_BACKEND_GET_CLASS().

    Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
    Reviewed-by: Akihiko Odaki <odaki@rsg.ci.i.u-tokyo.ac.jp>
    Reviewed-by: Mark Cave-Ayland <mark.caveayland@nutanix.com>

diff --git a/audio/alsaaudio.c b/audio/alsaaudio.c
index d008ce7b62..8f226b4261 100644
--- a/audio/alsaaudio.c
+++ b/audio/alsaaudio.c
@@ -922,21 +922,6 @@ audio_alsa_realize(AudioBackend *abe, Audiodev *dev, Error **errp)
     return audio_alsa_parent_class->realize(abe, dev, errp);
 }

-static struct audio_pcm_ops alsa_pcm_ops = {
-    .init_out = alsa_init_out,
-    .fini_out = alsa_fini_out,
-    .write    = alsa_write,
-    .buffer_get_free = alsa_buffer_get_free,
-    .run_buffer_out = audio_generic_run_buffer_out,
-    .enable_out = alsa_enable_out,
-
-    .init_in  = alsa_init_in,
-    .fini_in  = alsa_fini_in,
-    .read     = alsa_read,
-    .run_buffer_in = audio_generic_run_buffer_in,
-    .enable_in = alsa_enable_in,
-};
-
 static void audio_alsa_class_init(ObjectClass *klass, const void *data)
 {
     AudioBackendClass *b = AUDIO_BACKEND_CLASS(klass);
@@ -946,11 +931,23 @@ static void audio_alsa_class_init(ObjectClass *klass, const void *data)

     b->realize = audio_alsa_realize;
     k->name = "alsa";
-    k->pcm_ops = &alsa_pcm_ops;
     k->max_voices_out = INT_MAX;
     k->max_voices_in = INT_MAX;
     k->voice_size_out = sizeof(ALSAVoiceOut);
     k->voice_size_in = sizeof(ALSAVoiceIn);
+
+    k->init_out = alsa_init_out;
+    k->fini_out = alsa_fini_out;
+    k->write = alsa_write;
+    k->buffer_get_free = alsa_buffer_get_free;
+    k->run_buffer_out = audio_generic_run_buffer_out;
+    k->enable_out = alsa_enable_out;
+
+    k->init_in = alsa_init_in;
+    k->fini_in = alsa_fini_in;
+    k->read = alsa_read;
+    k->run_buffer_in = audio_generic_run_buffer_in;
+    k->enable_in = alsa_enable_in;
 }

 static const TypeInfo audio_types[] = {
diff --git a/audio/audio-mixeng-be.c b/audio/audio-mixeng-be.c
index 3a0a537713..17301ec80e 100644
--- a/audio/audio-mixeng-be.c
+++ b/audio/audio-mixeng-be.c
@@ -526,7 +526,7 @@ static size_t audio_pcm_sw_read(SWVoiceIn *sw, void *buf, size_t buf_len)

     audio_pcm_sw_resample_in(sw, live, frames_out_max, &total_in, &total_out);

-    if (!hw->pcm_ops->volume_in) {
+    if (!AUDIO_MIXENG_BACKEND_GET_CLASS(hw->s)->volume_in) {
         mixeng_volume(sw->resample_buf.buffer, total_out, &sw->vol);
     }
     sw->clip(buf, sw->resample_buf.buffer, total_out);
@@ -579,8 +579,10 @@ static size_t audio_pcm_hw_get_live_out (HWVoiceOut *hw, int *nb_live)

 static size_t audio_pcm_hw_get_free(HWVoiceOut *hw)
 {
-    return (hw->pcm_ops->buffer_get_free ? hw->pcm_ops->buffer_get_free(hw) :
-            INT_MAX) / hw->info.bytes_per_frame;
+    AudioMixengBackendClass *k = AUDIO_MIXENG_BACKEND_GET_CLASS(hw->s);
+
+    return (k->buffer_get_free ? k->buffer_get_free(hw) : INT_MAX) /
+        hw->info.bytes_per_frame;
 }

 static void audio_pcm_hw_clip_out(HWVoiceOut *hw, void *pcm_buf, size_t len)
@@ -673,7 +675,7 @@ static size_t audio_pcm_sw_write(SWVoiceOut *sw, void *buf, size_t buf_len)
     if (frames_in_max > sw->resample_buf.pos) {
         sw->conv(sw->resample_buf.buffer + sw->resample_buf.pos,
                  buf, frames_in_max - sw->resample_buf.pos);
-        if (!sw->hw->pcm_ops->volume_out) {
+        if (!AUDIO_MIXENG_BACKEND_GET_CLASS(sw->hw->s)->volume_out) {
             mixeng_volume(sw->resample_buf.buffer + sw->resample_buf.pos,
                           frames_in_max - sw->resample_buf.pos, &sw->vol);
         }
@@ -806,7 +808,7 @@ static size_t audio_mixeng_backend_write(AudioBackend *be, SWVoiceOut *sw,
     if (audio_get_pdo_out(hw->s->dev)->mixing_engine) {
         return audio_pcm_sw_write(sw, buf, size);
     } else {
-        return hw->pcm_ops->write(hw, buf, size);
+        return AUDIO_MIXENG_BACKEND_GET_CLASS(hw->s)->write(hw, buf, size);
     }
 }

@@ -829,7 +831,7 @@ static size_t audio_mixeng_backend_read(AudioBackend *be,
     if (audio_get_pdo_in(hw->s->dev)->mixing_engine) {
         return audio_pcm_sw_read(sw, buf, size);
     } else {
-        return hw->pcm_ops->read(hw, buf, size);
+        return AUDIO_MIXENG_BACKEND_GET_CLASS(hw->s)->read(hw, buf, size);
     }

 }
@@ -863,12 +865,14 @@ static void audio_mixeng_backend_set_active_out(AudioBackend *be, SWVoiceOut *sw
         SWVoiceCap *sc;

         if (on) {
+            AudioMixengBackendClass *k = AUDIO_MIXENG_BACKEND_GET_CLASS(s);
+
             hw->pending_disable = 0;
             if (!hw->enabled) {
                 hw->enabled = true;
                 if (runstate_is_running()) {
-                    if (hw->pcm_ops->enable_out) {
-                        hw->pcm_ops->enable_out(hw, true);
+                    if (k->enable_out) {
+                        k->enable_out(hw, true);
                     }
                     audio_reset_timer (s);
                 }
@@ -908,14 +912,15 @@ static void audio_mixeng_backend_set_active_in(AudioBackend *be, SWVoiceIn *sw,
     hw = sw->hw;
     if (sw->active != on) {
         AudioMixengBackend *s = sw->s;
+        AudioMixengBackendClass *k = AUDIO_MIXENG_BACKEND_GET_CLASS(s);
         SWVoiceIn *temp_sw;

         if (on) {
             if (!hw->enabled) {
                 hw->enabled = true;
                 if (runstate_is_running()) {
-                    if (hw->pcm_ops->enable_in) {
-                        hw->pcm_ops->enable_in(hw, true);
+                    if (k->enable_in) {
+                        k->enable_in(hw, true);
                     }
                     audio_reset_timer (s);
                 }
@@ -932,8 +937,8 @@ static void audio_mixeng_backend_set_active_in(AudioBackend *be, SWVoiceIn *sw,

                 if (nb_active == 1) {
                     hw->enabled = false;
-                    if (hw->pcm_ops->enable_in) {
-                        hw->pcm_ops->enable_in(hw, false);
+                    if (k->enable_in) {
+                        k->enable_in(hw, false);
                     }
                 }
             }
@@ -1040,12 +1045,13 @@ static void audio_capture_mix_and_clear(HWVoiceOut *hw, size_t rpos,

 static size_t audio_pcm_hw_run_out(HWVoiceOut *hw, size_t live)
 {
+    AudioMixengBackendClass *k = AUDIO_MIXENG_BACKEND_GET_CLASS(hw->s);
     size_t clipped = 0;

     while (live) {
         size_t size = live * hw->info.bytes_per_frame;
         size_t decr, proc;
-        void *buf = hw->pcm_ops->get_buffer_out(hw, &size);
+        void *buf = k->get_buffer_out(hw, &size);

         if (size == 0) {
             break;
@@ -1055,8 +1061,7 @@ static size_t audio_pcm_hw_run_out(HWVoiceOut *hw, size_t live)
         if (buf) {
             audio_pcm_hw_clip_out(hw, buf, decr);
         }
-        proc = hw->pcm_ops->put_buffer_out(hw, buf,
-                                           decr * hw->info.bytes_per_frame) /
+        proc = k->put_buffer_out(hw, buf, decr * hw->info.bytes_per_frame) /
             hw->info.bytes_per_frame;

         live -= proc;
@@ -1068,8 +1073,8 @@ static size_t audio_pcm_hw_run_out(HWVoiceOut *hw, size_t live)
         }
     }

-    if (hw->pcm_ops->run_buffer_out) {
-        hw->pcm_ops->run_buffer_out(hw);
+    if (k->run_buffer_out) {
+        k->run_buffer_out(hw);
     }

     return clipped;
@@ -1077,6 +1082,7 @@ static size_t audio_pcm_hw_run_out(HWVoiceOut *hw, size_t live)

 static void audio_run_out(AudioMixengBackend *s)
 {
+    AudioMixengBackendClass *k = AUDIO_MIXENG_BACKEND_GET_CLASS(s);
     HWVoiceOut *hw = NULL;
     SWVoiceOut *sw;

@@ -1092,8 +1098,8 @@ static void audio_run_out(AudioMixengBackend *s)
             if (hw->pending_disable) {
                 hw->enabled = false;
                 hw->pending_disable = false;
-                if (hw->pcm_ops->enable_out) {
-                    hw->pcm_ops->enable_out(hw, false);
+                if (k->enable_out) {
+                    k->enable_out(hw, false);
                 }
             }

@@ -1102,8 +1108,8 @@ static void audio_run_out(AudioMixengBackend *s)
                                 hw_free * sw->info.bytes_per_frame);
             }

-            if (hw->pcm_ops->run_buffer_out) {
-                hw->pcm_ops->run_buffer_out(hw);
+            if (k->run_buffer_out) {
+                k->run_buffer_out(hw);
             }

             continue;
@@ -1146,8 +1152,8 @@ static void audio_run_out(AudioMixengBackend *s)
 #endif
             hw->enabled = false;
             hw->pending_disable = false;
-            if (hw->pcm_ops->enable_out) {
-                hw->pcm_ops->enable_out(hw, false);
+            if (k->enable_out) {
+                k->enable_out(hw, false);
             }
             for (sc = hw->cap_head.lh_first; sc; sc = sc->entries.le_next) {
                 sc->sw.active = false;
@@ -1157,8 +1163,8 @@ static void audio_run_out(AudioMixengBackend *s)
         }

         if (!live) {
-            if (hw->pcm_ops->run_buffer_out) {
-                hw->pcm_ops->run_buffer_out(hw);
+            if (k->run_buffer_out) {
+                k->run_buffer_out(hw);
             }
             continue;
         }
@@ -1202,16 +1208,17 @@ static void audio_run_out(AudioMixengBackend *s)

 static size_t audio_pcm_hw_run_in(HWVoiceIn *hw, size_t samples)
 {
+    AudioMixengBackendClass *k = AUDIO_MIXENG_BACKEND_GET_CLASS(hw->s);
     size_t conv = 0;

-    if (hw->pcm_ops->run_buffer_in) {
-        hw->pcm_ops->run_buffer_in(hw);
+    if (k->run_buffer_in) {
+        k->run_buffer_in(hw);
     }

     while (samples) {
         size_t proc;
         size_t size = samples * hw->info.bytes_per_frame;
-        void *buf = hw->pcm_ops->get_buffer_in(hw, &size);
+        void *buf = k->get_buffer_in(hw, &size);

         assert(size % hw->info.bytes_per_frame == 0);
         if (size == 0) {
@@ -1222,7 +1229,7 @@ static size_t audio_pcm_hw_run_in(HWVoiceIn *hw, size_t samples)

         samples -= proc;
         conv += proc;
-        hw->pcm_ops->put_buffer_in(hw, buf, proc * hw->info.bytes_per_frame);
+        k->put_buffer_in(hw, buf, proc * hw->info.bytes_per_frame);
     }

     return conv;
@@ -1367,6 +1374,8 @@ void audio_run(AudioMixengBackend *s, const char *msg)

 void audio_generic_run_buffer_in(HWVoiceIn *hw)
 {
+    AudioMixengBackendClass *k = AUDIO_MIXENG_BACKEND_GET_CLASS(hw->s);
+
     if (unlikely(!hw->buf_emul)) {
         hw->size_emul = hw->samples * hw->info.bytes_per_frame;
         hw->buf_emul = g_malloc(hw->size_emul);
@@ -1376,8 +1385,7 @@ void audio_generic_run_buffer_in(HWVoiceIn *hw)
     while (hw->pending_emul < hw->size_emul) {
         size_t read_len = MIN(hw->size_emul - hw->pos_emul,
                               hw->size_emul - hw->pending_emul);
-        size_t read = hw->pcm_ops->read(hw, hw->buf_emul + hw->pos_emul,
-                                        read_len);
+        size_t read = k->read(hw, hw->buf_emul + hw->pos_emul, read_len);
         hw->pending_emul += read;
         hw->pos_emul = (hw->pos_emul + read) % hw->size_emul;
         if (read < read_len) {
@@ -1415,6 +1423,8 @@ size_t audio_generic_buffer_get_free(HWVoiceOut *hw)

 void audio_generic_run_buffer_out(HWVoiceOut *hw)
 {
+    AudioMixengBackendClass *k = AUDIO_MIXENG_BACKEND_GET_CLASS(hw->s);
+
     while (hw->pending_emul) {
         size_t write_len, written, start;

@@ -1423,7 +1433,7 @@ void audio_generic_run_buffer_out(HWVoiceOut *hw)

         write_len = MIN(hw->pending_emul, hw->size_emul - start);

-        written = hw->pcm_ops->write(hw, hw->buf_emul + start, write_len);
+        written = k->write(hw, hw->buf_emul + start, write_len);
         hw->pending_emul -= written;

         if (written < write_len) {
@@ -1458,10 +1468,11 @@ size_t audio_generic_put_buffer_out(HWVoiceOut *hw, void *buf, size_t size)

 size_t audio_generic_write(HWVoiceOut *hw, void *buf, size_t size)
 {
+    AudioMixengBackendClass *k = AUDIO_MIXENG_BACKEND_GET_CLASS(hw->s);
     size_t total = 0;

-    if (hw->pcm_ops->buffer_get_free) {
-        size_t free = hw->pcm_ops->buffer_get_free(hw);
+    if (k->buffer_get_free) {
+        size_t free = k->buffer_get_free(hw);

         size = MIN(size, free);
     }
@@ -1469,7 +1480,7 @@ size_t audio_generic_write(HWVoiceOut *hw, void *buf, size_t size)
     while (total < size) {
         size_t dst_size = size - total;
         size_t copy_size, proc;
-        void *dst = hw->pcm_ops->get_buffer_out(hw, &dst_size);
+        void *dst = k->get_buffer_out(hw, &dst_size);

         if (dst_size == 0) {
             break;
@@ -1479,7 +1490,7 @@ size_t audio_generic_write(HWVoiceOut *hw, void *buf, size_t size)
         if (dst) {
             memcpy(dst, (char *)buf + total, copy_size);
         }
-        proc = hw->pcm_ops->put_buffer_out(hw, dst, copy_size);
+        proc = k->put_buffer_out(hw, dst, copy_size);
         total += proc;

         if (proc == 0 || proc < copy_size) {
@@ -1492,22 +1503,23 @@ size_t audio_generic_write(HWVoiceOut *hw, void *buf, size_t size)

 size_t audio_generic_read(HWVoiceIn *hw, void *buf, size_t size)
 {
+    AudioMixengBackendClass *k = AUDIO_MIXENG_BACKEND_GET_CLASS(hw->s);
     size_t total = 0;

-    if (hw->pcm_ops->run_buffer_in) {
-        hw->pcm_ops->run_buffer_in(hw);
+    if (k->run_buffer_in) {
+        k->run_buffer_in(hw);
     }

     while (total < size) {
         size_t src_size = size - total;
-        void *src = hw->pcm_ops->get_buffer_in(hw, &src_size);
+        void *src = k->get_buffer_in(hw, &src_size);

         if (src_size == 0) {
             break;
         }

         memcpy((char *)buf + total, src, src_size);
-        hw->pcm_ops->put_buffer_in(hw, src, src_size);
+        k->put_buffer_in(hw, src, src_size);
         total += src_size;
     }

@@ -1521,13 +1533,13 @@ static bool audio_mixeng_backend_realize(AudioBackend *abe,
     AudioMixengBackendClass *k = AUDIO_MIXENG_BACKEND_GET_CLASS(be);

     be->dev = dev;
-    if (!k->pcm_ops->get_buffer_in) {
-        k->pcm_ops->get_buffer_in = audio_generic_get_buffer_in;
-        k->pcm_ops->put_buffer_in = audio_generic_put_buffer_in;
+    if (!k->get_buffer_in) {
+        k->get_buffer_in = audio_generic_get_buffer_in;
+        k->put_buffer_in = audio_generic_put_buffer_in;
     }
-    if (!k->pcm_ops->get_buffer_out) {
-        k->pcm_ops->get_buffer_out = audio_generic_get_buffer_out;
-        k->pcm_ops->put_buffer_out = audio_generic_put_buffer_out;
+    if (!k->get_buffer_out) {
+        k->get_buffer_out = audio_generic_get_buffer_out;
+        k->put_buffer_out = audio_generic_put_buffer_out;
     }

     audio_init_nb_voices_out(be, k, 1);
@@ -1546,18 +1558,19 @@ static void audio_vm_change_state_handler (void *opaque, bool running,
                                            RunState state)
 {
     AudioMixengBackend *s = opaque;
+    AudioMixengBackendClass *k = AUDIO_MIXENG_BACKEND_GET_CLASS(s);
     HWVoiceOut *hwo = NULL;
     HWVoiceIn *hwi = NULL;

     while ((hwo = audio_pcm_hw_find_any_enabled_out(s, hwo))) {
-        if (hwo->pcm_ops->enable_out) {
-            hwo->pcm_ops->enable_out(hwo, running);
+        if (k->enable_out) {
+            k->enable_out(hwo, running);
         }
     }

     while ((hwi = audio_pcm_hw_find_any_enabled_in(s, hwi))) {
-        if (hwi->pcm_ops->enable_in) {
-            hwi->pcm_ops->enable_in(hwi, running);
+        if (k->enable_in) {
+            k->enable_in(hwi, running);
         }
     }
     audio_reset_timer (s);
@@ -1627,16 +1640,17 @@ static void audio_mixeng_backend_init(Object *obj)
 static void audio_mixeng_backend_finalize(Object *obj)
 {
     AudioMixengBackend *s = AUDIO_MIXENG_BACKEND(obj);
+    AudioMixengBackendClass *k = AUDIO_MIXENG_BACKEND_GET_CLASS(s);
     HWVoiceOut *hwo, *hwon;
     HWVoiceIn *hwi, *hwin;

     QLIST_FOREACH_SAFE(hwo, &s->hw_head_out, entries, hwon) {
         SWVoiceCap *sc;

-        if (hwo->enabled && hwo->pcm_ops->enable_out) {
-            hwo->pcm_ops->enable_out(hwo, false);
+        if (hwo->enabled && k->enable_out) {
+            k->enable_out(hwo, false);
         }
-        hwo->pcm_ops->fini_out (hwo);
+        k->fini_out(hwo);

         for (sc = hwo->cap_head.lh_first; sc; sc = sc->entries.le_next) {
             CaptureVoiceOut *cap = sc->cap;
@@ -1650,10 +1664,10 @@ static void audio_mixeng_backend_finalize(Object *obj)
     }

     QLIST_FOREACH_SAFE(hwi, &s->hw_head_in, entries, hwin) {
-        if (hwi->enabled && hwi->pcm_ops->enable_in) {
-            hwi->pcm_ops->enable_in(hwi, false);
+        if (hwi->enabled && k->enable_in) {
+            k->enable_in(hwi, false);
         }
-        hwi->pcm_ops->fini_in (hwi);
+        k->fini_in(hwi);
         QLIST_REMOVE(hwi, entries);
     }

@@ -1694,8 +1708,6 @@ static const VMStateDescription vmstate_audio = {
     }
 };

-static struct audio_pcm_ops capture_pcm_ops;
-
 static CaptureVoiceOut *audio_mixeng_backend_add_capture(
     AudioBackend *be,
     struct audsettings *as,
@@ -1736,7 +1748,6 @@ static CaptureVoiceOut *audio_mixeng_backend_add_capture(

         hw = &cap->hw;
         hw->s = s;
-        hw->pcm_ops = &capture_pcm_ops;
         QLIST_INIT (&hw->sw_head);
         QLIST_INIT (&cap->cb_head);

@@ -1817,14 +1828,15 @@ static void audio_mixeng_backend_set_volume_out(AudioBackend *be, SWVoiceOut *sw
 {
     if (sw) {
         HWVoiceOut *hw = sw->hw;
+        AudioMixengBackendClass *k = AUDIO_MIXENG_BACKEND_GET_CLASS(hw->s);

         sw->vol.mute = vol->mute;
         sw->vol.l = nominal_volume.l * vol->vol[0] / 255;
         sw->vol.r = nominal_volume.l * vol->vol[vol->channels > 1 ? 1 : 0] /
             255;

-        if (hw->pcm_ops->volume_out) {
-            hw->pcm_ops->volume_out(hw, vol);
+        if (k->volume_out) {
+            k->volume_out(hw, vol);
         }
     }
 }
@@ -1834,14 +1846,15 @@ static void audio_mixeng_backend_set_volume_in(AudioBackend *be, SWVoiceIn *sw,
 {
     if (sw) {
         HWVoiceIn *hw = sw->hw;
+        AudioMixengBackendClass *k = AUDIO_MIXENG_BACKEND_GET_CLASS(hw->s);

         sw->vol.mute = vol->mute;
         sw->vol.l = nominal_volume.l * vol->vol[0] / 255;
         sw->vol.r = nominal_volume.r * vol->vol[vol->channels > 1 ? 1 : 0] /
             255;

-        if (hw->pcm_ops->volume_in) {
-            hw->pcm_ops->volume_in(hw, vol);
+        if (k->volume_in) {
+            k->volume_in(hw, vol);
         }
     }
 }
diff --git a/audio/audio_int.h b/audio/audio_int.h
index bd9c7a29e4..5334c4baad 100644
--- a/audio/audio_int.h
+++ b/audio/audio_int.h
@@ -39,8 +39,6 @@ AUD_vlog(const char *cap, const char *fmt, va_list ap);
 void G_GNUC_PRINTF(2, 3)
 AUD_log(const char *cap, const char *fmt, ...);

-struct audio_pcm_ops;
-
 struct audio_callback {
     void *opaque;
     audio_callback_fn fn;
@@ -81,7 +79,6 @@ typedef struct HWVoiceOut {
     size_t samples;
     QLIST_HEAD (sw_out_listhead, SWVoiceOut) sw_head;
     QLIST_HEAD (sw_cap_listhead, SWVoiceCap) cap_head;
-    struct audio_pcm_ops *pcm_ops;
     QLIST_ENTRY (HWVoiceOut) entries;
 } HWVoiceOut;

@@ -101,7 +98,6 @@ typedef struct HWVoiceIn {

     size_t samples;
     QLIST_HEAD (sw_in_listhead, SWVoiceIn) sw_head;
-    struct audio_pcm_ops *pcm_ops;
     QLIST_ENTRY (HWVoiceIn) entries;
 } HWVoiceIn;

@@ -136,40 +132,6 @@ struct SWVoiceIn {
     QLIST_ENTRY (SWVoiceIn) entries;
 };

-struct audio_pcm_ops {
-    int    (*init_out)(HWVoiceOut *hw, audsettings *as);
-    void   (*fini_out)(HWVoiceOut *hw);
-    size_t (*write)   (HWVoiceOut *hw, void *buf, size_t size);
-    void   (*run_buffer_out)(HWVoiceOut *hw);
-    /*
-     * Get the free output buffer size. This is an upper limit. The size
-     * returned by function get_buffer_out may be smaller.
-     */
-    size_t (*buffer_get_free)(HWVoiceOut *hw);
-    /*
-     * get a buffer that after later can be passed to put_buffer_out; optional
-     * returns the buffer, and writes it's size to size (in bytes)
-     */
-    void  *(*get_buffer_out)(HWVoiceOut *hw, size_t *size);
-    /*
-     * put back the buffer returned by get_buffer_out; optional
-     * buf must be equal the pointer returned by get_buffer_out,
-     * size may be smaller
-     */
-    size_t (*put_buffer_out)(HWVoiceOut *hw, void *buf, size_t size);
-    void   (*enable_out)(HWVoiceOut *hw, bool enable);
-    void   (*volume_out)(HWVoiceOut *hw, Volume *vol);
-
-    int    (*init_in) (HWVoiceIn *hw, audsettings *as);
-    void   (*fini_in) (HWVoiceIn *hw);
-    size_t (*read)    (HWVoiceIn *hw, void *buf, size_t size);
-    void   (*run_buffer_in)(HWVoiceIn *hw);
-    void  *(*get_buffer_in)(HWVoiceIn *hw, size_t *size);
-    void   (*put_buffer_in)(HWVoiceIn *hw, void *buf, size_t size);
-    void   (*enable_in)(HWVoiceIn *hw, bool enable);
-    void   (*volume_in)(HWVoiceIn *hw, Volume *vol);
-};
-
 audsettings audiodev_to_audsettings(AudiodevPerDirectionOptions *pdo);
 int audioformat_bytes_per_sample(AudioFormat fmt);
 int audio_buffer_frames(AudiodevPerDirectionOptions *pdo,
@@ -220,11 +182,42 @@ struct AudioMixengBackendClass {
     AudioBackendClass parent_class;

     const char *name;
-    struct audio_pcm_ops *pcm_ops;
     int max_voices_out;
     int max_voices_in;
     size_t voice_size_out;
     size_t voice_size_in;
+
+    int    (*init_out)(HWVoiceOut *hw, audsettings *as);
+    void   (*fini_out)(HWVoiceOut *hw);
+    size_t (*write)   (HWVoiceOut *hw, void *buf, size_t size);
+    void   (*run_buffer_out)(HWVoiceOut *hw);
+    /*
+     * Get the free output buffer size. This is an upper limit. The size
+     * returned by function get_buffer_out may be smaller.
+     */
+    size_t (*buffer_get_free)(HWVoiceOut *hw);
+    /*
+     * get a buffer that after later can be passed to put_buffer_out; optional
+     * returns the buffer, and writes it's size to size (in bytes)
+     */
+    void  *(*get_buffer_out)(HWVoiceOut *hw, size_t *size);
+    /*
+     * put back the buffer returned by get_buffer_out; optional
+     * buf must be equal the pointer returned by get_buffer_out,
+     * size may be smaller
+     */
+    size_t (*put_buffer_out)(HWVoiceOut *hw, void *buf, size_t size);
+    void   (*enable_out)(HWVoiceOut *hw, bool enable);
+    void   (*volume_out)(HWVoiceOut *hw, Volume *vol);
+
+    int    (*init_in) (HWVoiceIn *hw, audsettings *as);
+    void   (*fini_in) (HWVoiceIn *hw);
+    size_t (*read)    (HWVoiceIn *hw, void *buf, size_t size);
+    void   (*run_buffer_in)(HWVoiceIn *hw);
+    void  *(*get_buffer_in)(HWVoiceIn *hw, size_t *size);
+    void   (*put_buffer_in)(HWVoiceIn *hw, void *buf, size_t size);
+    void   (*enable_in)(HWVoiceIn *hw, bool enable);
+    void   (*volume_in)(HWVoiceIn *hw, Volume *vol);
 };

 struct AudioMixengBackend {
diff --git a/audio/audio_template.h b/audio/audio_template.h
index 7187571c66..08d6042258 100644
--- a/audio/audio_template.h
+++ b/audio/audio_template.h
@@ -223,13 +223,14 @@ static void glue (audio_pcm_hw_gc_, TYPE) (HW **hwp)
 {
     HW *hw = *hwp;
     AudioMixengBackend *s = hw->s;
+    AudioMixengBackendClass *k = AUDIO_MIXENG_BACKEND_GET_CLASS(s);

     if (!hw->sw_head.lh_first) {
 #ifdef DAC
         audio_detach_capture(hw);
 #endif
         QLIST_REMOVE(hw, entries);
-        glue(hw->pcm_ops->fini_, TYPE) (hw);
+        glue(k->fini_, TYPE)(hw);
         glue(s->nb_hw_voices_, TYPE) += 1;
         glue(audio_pcm_hw_free_resources_ , TYPE) (hw);
         object_unref(hw->s);
@@ -274,8 +275,8 @@ static HW *glue(audio_pcm_hw_add_new_, TYPE)(AudioMixengBackend *s,
         return NULL;
     }

-    if (audio_bug(__func__, !k->pcm_ops)) {
-        dolog("No host audio driver or missing pcm_ops\n");
+    if (audio_bug(__func__, !glue(k->init_, TYPE))) {
+        dolog("No host audio driver or missing init_%s\n", NAME);
         return NULL;
     }

@@ -285,13 +286,12 @@ static HW *glue(audio_pcm_hw_add_new_, TYPE)(AudioMixengBackend *s,
      */
     hw = g_malloc0(glue(k->voice_size_, TYPE));
     hw->s = AUDIO_MIXENG_BACKEND(object_ref(s));
-    hw->pcm_ops = k->pcm_ops;

     QLIST_INIT (&hw->sw_head);
 #ifdef DAC
     QLIST_INIT (&hw->cap_head);
 #endif
-    if (glue (hw->pcm_ops->init_, TYPE) (hw, as)) {
+    if (glue(k->init_, TYPE)(hw, as)) {
         goto err0;
     }

@@ -330,7 +330,7 @@ static HW *glue(audio_pcm_hw_add_new_, TYPE)(AudioMixengBackend *s,
     return hw;

  err1:
-    glue (hw->pcm_ops->fini_, TYPE) (hw);
+    glue(k->fini_, TYPE)(hw);
  err0:
     object_unref(hw->s);
     g_free (hw);
@@ -495,6 +495,7 @@ static SW *glue(audio_mixeng_backend_open_, TYPE) (
     const struct audsettings *as)
 {
     AudioMixengBackend *s = AUDIO_MIXENG_BACKEND(be);
+    AudioMixengBackendClass *k;
     AudiodevPerDirectionOptions *pdo;

     if (audio_bug(__func__, !be || !name || !callback_fn || !as)) {
@@ -503,6 +504,7 @@ static SW *glue(audio_mixeng_backend_open_, TYPE) (
         goto fail;
     }

+    k = AUDIO_MIXENG_BACKEND_GET_CLASS(s);
     pdo = glue(audio_get_pdo_, TYPE)(s->dev);

     ldebug ("open %s, freq %d, nchannels %d, fmt %d\n",
@@ -513,7 +515,7 @@ static SW *glue(audio_mixeng_backend_open_, TYPE) (
         goto fail;
     }

-    if (audio_bug(__func__, !AUDIO_MIXENG_BACKEND_GET_CLASS(s)->pcm_ops)) {
+    if (audio_bug(__func__, !glue(k->init_, TYPE))) {
         dolog("Can not open `%s' (no host audio driver)\n", name);
         goto fail;
     }
diff --git a/audio/coreaudio.m b/audio/coreaudio.m
index e9274976f9..561c08f47c 100644
--- a/audio/coreaudio.m
+++ b/audio/coreaudio.m
@@ -646,30 +646,27 @@ static void coreaudio_enable_out(HWVoiceOut *hw, bool enable)
     update_device_playback_state(core);
 }

-static struct audio_pcm_ops coreaudio_pcm_ops = {
-    .init_out = coreaudio_init_out,
-    .fini_out = coreaudio_fini_out,
-  /* wrapper for audio_generic_write */
-    .write    = coreaudio_write,
-  /* wrapper for audio_generic_buffer_get_free */
-    .buffer_get_free = coreaudio_buffer_get_free,
-  /* wrapper for audio_generic_get_buffer_out */
-    .get_buffer_out = coreaudio_get_buffer_out,
-  /* wrapper for audio_generic_put_buffer_out */
-    .put_buffer_out = coreaudio_put_buffer_out,
-    .enable_out = coreaudio_enable_out
-};
-
 static void audio_coreaudio_class_init(ObjectClass *klass, const void *data)
 {
     AudioMixengBackendClass *k = AUDIO_MIXENG_BACKEND_CLASS(klass);

     k->name = "coreaudio";
-    k->pcm_ops = &coreaudio_pcm_ops;
     k->max_voices_out = 1;
     k->max_voices_in = 0;
     k->voice_size_out = sizeof(coreaudioVoiceOut);
     k->voice_size_in = 0;
+
+    k->init_out = coreaudio_init_out;
+    k->fini_out = coreaudio_fini_out;
+    /* wrapper for audio_generic_write */
+    k->write = coreaudio_write;
+    /* wrapper for audio_generic_buffer_get_free */
+    k->buffer_get_free = coreaudio_buffer_get_free;
+    /* wrapper for audio_generic_get_buffer_out */
+    k->get_buffer_out = coreaudio_get_buffer_out;
+    /* wrapper for audio_generic_put_buffer_out */
+    k->put_buffer_out = coreaudio_put_buffer_out;
+    k->enable_out = coreaudio_enable_out;
 }

 static const TypeInfo audio_types[] = {
diff --git a/audio/dbusaudio.c b/audio/dbusaudio.c
index 82e76c41f9..d8e548bf46 100644
--- a/audio/dbusaudio.c
+++ b/audio/dbusaudio.c
@@ -691,23 +691,6 @@ dbus_audio_set_server(AudioBackend *s,
     return true;
 }

-static struct audio_pcm_ops dbus_pcm_ops = {
-    .init_out = dbus_init_out,
-    .fini_out = dbus_fini_out,
-    .write    = audio_generic_write,
-    .get_buffer_out = dbus_get_buffer_out,
-    .put_buffer_out = dbus_put_buffer_out,
-    .enable_out = dbus_enable_out,
-    .volume_out = dbus_volume_out,
-
-    .init_in  = dbus_init_in,
-    .fini_in  = dbus_fini_in,
-    .read     = dbus_read,
-    .run_buffer_in = audio_generic_run_buffer_in,
-    .enable_in = dbus_enable_in,
-    .volume_in = dbus_volume_in,
-};
-
 static void audio_dbus_class_init(ObjectClass *klass, const void *data)
 {
     AudioBackendClass *b = AUDIO_BACKEND_CLASS(klass);
@@ -718,11 +701,25 @@ static void audio_dbus_class_init(ObjectClass *klass, const void *data)
     b->realize = audio_dbus_realize;
     b->set_dbus_server = dbus_audio_set_server;
     k->name = "dbus";
-    k->pcm_ops = &dbus_pcm_ops;
     k->max_voices_out = INT_MAX;
     k->max_voices_in = INT_MAX;
     k->voice_size_out = sizeof(DBusVoiceOut);
     k->voice_size_in = sizeof(DBusVoiceIn);
+
+    k->init_out = dbus_init_out;
+    k->fini_out = dbus_fini_out;
+    k->write = audio_generic_write;
+    k->get_buffer_out = dbus_get_buffer_out;
+    k->put_buffer_out = dbus_put_buffer_out;
+    k->enable_out = dbus_enable_out;
+    k->volume_out = dbus_volume_out;
+
+    k->init_in = dbus_init_in;
+    k->fini_in = dbus_fini_in;
+    k->read = dbus_read;
+    k->run_buffer_in = audio_generic_run_buffer_in;
+    k->enable_in = dbus_enable_in;
+    k->volume_in = dbus_volume_in;
 }

 static const TypeInfo audio_types[] = {
diff --git a/audio/dsoundaudio.c b/audio/dsoundaudio.c
index e35b7fc233..2c592c5666 100644
--- a/audio/dsoundaudio.c
+++ b/audio/dsoundaudio.c
@@ -667,23 +667,6 @@ audio_dsound_realize(AudioBackend *abe, Audiodev *dev, Error **errp)
     return true;
 }

-static struct audio_pcm_ops dsound_pcm_ops = {
-    .init_out = dsound_init_out,
-    .fini_out = dsound_fini_out,
-    .write    = audio_generic_write,
-    .buffer_get_free = dsound_buffer_get_free,
-    .get_buffer_out = dsound_get_buffer_out,
-    .put_buffer_out = dsound_put_buffer_out,
-    .enable_out = dsound_enable_out,
-
-    .init_in  = dsound_init_in,
-    .fini_in  = dsound_fini_in,
-    .read     = audio_generic_read,
-    .get_buffer_in = dsound_get_buffer_in,
-    .put_buffer_in = dsound_put_buffer_in,
-    .enable_in = dsound_enable_in,
-};
-
 static void audio_dsound_class_init(ObjectClass *klass, const void *data)
 {
     AudioBackendClass *b = AUDIO_BACKEND_CLASS(klass);
@@ -693,11 +676,25 @@ static void audio_dsound_class_init(ObjectClass *klass, const void *data)

     b->realize = audio_dsound_realize;
     k->name = "dsound";
-    k->pcm_ops = &dsound_pcm_ops;
     k->max_voices_out = INT_MAX;
     k->max_voices_in = 1;
     k->voice_size_out = sizeof(DSoundVoiceOut);
     k->voice_size_in = sizeof(DSoundVoiceIn);
+
+    k->init_out = dsound_init_out;
+    k->fini_out = dsound_fini_out;
+    k->write = audio_generic_write;
+    k->buffer_get_free = dsound_buffer_get_free;
+    k->get_buffer_out = dsound_get_buffer_out;
+    k->put_buffer_out = dsound_put_buffer_out;
+    k->enable_out = dsound_enable_out;
+
+    k->init_in = dsound_init_in;
+    k->fini_in = dsound_fini_in;
+    k->read = audio_generic_read;
+    k->get_buffer_in = dsound_get_buffer_in;
+    k->put_buffer_in = dsound_put_buffer_in;
+    k->enable_in = dsound_enable_in;
 }

 static const TypeInfo audio_types[] = {
diff --git a/audio/jackaudio.c b/audio/jackaudio.c
index 7caa2ddf43..e415e94e6e 100644
--- a/audio/jackaudio.c
+++ b/audio/jackaudio.c
@@ -652,21 +652,6 @@ static int qjack_thread_creator(jack_native_thread_t *thread,
 }
 #endif

-static struct audio_pcm_ops jack_pcm_ops = {
-    .init_out       = qjack_init_out,
-    .fini_out       = qjack_fini_out,
-    .write          = qjack_write,
-    .buffer_get_free = audio_generic_buffer_get_free,
-    .run_buffer_out = audio_generic_run_buffer_out,
-    .enable_out     = qjack_enable_out,
-
-    .init_in        = qjack_init_in,
-    .fini_in        = qjack_fini_in,
-    .read           = qjack_read,
-    .run_buffer_in  = audio_generic_run_buffer_in,
-    .enable_in      = qjack_enable_in
-};
-
 static void qjack_error(const char *msg)
 {
     dolog("E: %s\n", msg);
@@ -682,11 +667,23 @@ static void audio_jack_class_init(ObjectClass *klass, const void *data)
     AudioMixengBackendClass *k = AUDIO_MIXENG_BACKEND_CLASS(klass);

     k->name = "jack";
-    k->pcm_ops = &jack_pcm_ops;
     k->max_voices_out = INT_MAX;
     k->max_voices_in = INT_MAX;
     k->voice_size_out = sizeof(QJackOut);
     k->voice_size_in = sizeof(QJackIn);
+
+    k->init_out = qjack_init_out;
+    k->fini_out = qjack_fini_out;
+    k->write = qjack_write;
+    k->buffer_get_free = audio_generic_buffer_get_free;
+    k->run_buffer_out = audio_generic_run_buffer_out;
+    k->enable_out = qjack_enable_out;
+
+    k->init_in = qjack_init_in;
+    k->fini_in = qjack_fini_in;
+    k->read = qjack_read;
+    k->run_buffer_in = audio_generic_run_buffer_in;
+    k->enable_in = qjack_enable_in;
 }

 static const TypeInfo audio_types[] = {
diff --git a/audio/noaudio.c b/audio/noaudio.c
index be2e2e684c..e056813181 100644
--- a/audio/noaudio.c
+++ b/audio/noaudio.c
@@ -110,31 +110,28 @@ static void no_enable_in(HWVoiceIn *hw, bool enable)
     }
 }

-static struct audio_pcm_ops no_pcm_ops = {
-    .init_out = no_init_out,
-    .fini_out = no_fini_out,
-    .write    = no_write,
-    .buffer_get_free = audio_generic_buffer_get_free,
-    .run_buffer_out = audio_generic_run_buffer_out,
-    .enable_out = no_enable_out,
-
-    .init_in  = no_init_in,
-    .fini_in  = no_fini_in,
-    .read     = no_read,
-    .run_buffer_in = audio_generic_run_buffer_in,
-    .enable_in = no_enable_in
-};
-
 static void audio_none_class_init(ObjectClass *klass, const void *data)
 {
     AudioMixengBackendClass *k = AUDIO_MIXENG_BACKEND_CLASS(klass);

     k->name = "none";
-    k->pcm_ops = &no_pcm_ops;
     k->max_voices_out = INT_MAX;
     k->max_voices_in = INT_MAX;
     k->voice_size_out = sizeof(NoVoiceOut);
     k->voice_size_in = sizeof(NoVoiceIn);
+
+    k->init_out = no_init_out;
+    k->fini_out = no_fini_out;
+    k->write = no_write;
+    k->buffer_get_free = audio_generic_buffer_get_free;
+    k->run_buffer_out = audio_generic_run_buffer_out;
+    k->enable_out = no_enable_out;
+
+    k->init_in = no_init_in;
+    k->fini_in = no_fini_in;
+    k->read = no_read;
+    k->run_buffer_in = audio_generic_run_buffer_in;
+    k->enable_in = no_enable_in;
 }

 static const TypeInfo audio_types[] = {
diff --git a/audio/ossaudio.c b/audio/ossaudio.c
index 0ad974e20c..d12c65dd0d 100644
--- a/audio/ossaudio.c
+++ b/audio/ossaudio.c
@@ -755,23 +755,6 @@ audio_oss_realize(AudioBackend *abe, Audiodev *dev, Error **errp)
     return audio_oss_parent_class->realize(abe, dev, errp);
 }

-static struct audio_pcm_ops oss_pcm_ops = {
-    .init_out = oss_init_out,
-    .fini_out = oss_fini_out,
-    .write    = oss_write,
-    .buffer_get_free = oss_buffer_get_free,
-    .run_buffer_out = oss_run_buffer_out,
-    .get_buffer_out = oss_get_buffer_out,
-    .put_buffer_out = oss_put_buffer_out,
-    .enable_out = oss_enable_out,
-
-    .init_in  = oss_init_in,
-    .fini_in  = oss_fini_in,
-    .read     = oss_read,
-    .run_buffer_in = audio_generic_run_buffer_in,
-    .enable_in = oss_enable_in
-};
-
 static void audio_oss_class_init(ObjectClass *klass, const void *data)
 {
     AudioBackendClass *b = AUDIO_BACKEND_CLASS(klass);
@@ -781,11 +764,25 @@ static void audio_oss_class_init(ObjectClass *klass, const void *data)

     b->realize = audio_oss_realize;
     k->name = "oss";
-    k->pcm_ops = &oss_pcm_ops;
     k->max_voices_out = INT_MAX;
     k->max_voices_in = INT_MAX;
     k->voice_size_out = sizeof(OSSVoiceOut);
     k->voice_size_in = sizeof(OSSVoiceIn);
+
+    k->init_out = oss_init_out;
+    k->fini_out = oss_fini_out;
+    k->write = oss_write;
+    k->buffer_get_free = oss_buffer_get_free;
+    k->run_buffer_out = oss_run_buffer_out;
+    k->get_buffer_out = oss_get_buffer_out;
+    k->put_buffer_out = oss_put_buffer_out;
+    k->enable_out = oss_enable_out;
+
+    k->init_in = oss_init_in;
+    k->fini_in = oss_fini_in;
+    k->read = oss_read;
+    k->run_buffer_in = audio_generic_run_buffer_in;
+    k->enable_in = oss_enable_in;
 }

 static const TypeInfo audio_types[] = {
diff --git a/audio/paaudio.c b/audio/paaudio.c
index 5758050cb5..b7826402e1 100644
--- a/audio/paaudio.c
+++ b/audio/paaudio.c
@@ -913,23 +913,6 @@ static void audio_pa_finalize(Object *obj)
     }
 }

-static struct audio_pcm_ops qpa_pcm_ops = {
-    .init_out = qpa_init_out,
-    .fini_out = qpa_fini_out,
-    .write    = qpa_write,
-    .buffer_get_free = qpa_buffer_get_free,
-    .get_buffer_out = qpa_get_buffer_out,
-    .put_buffer_out = qpa_put_buffer_out,
-    .volume_out = qpa_volume_out,
-
-    .init_in  = qpa_init_in,
-    .fini_in  = qpa_fini_in,
-    .read     = qpa_read,
-    .get_buffer_in = qpa_get_buffer_in,
-    .put_buffer_in = qpa_put_buffer_in,
-    .volume_in = qpa_volume_in
-};
-
 static void audio_pa_class_init(ObjectClass *klass, const void *data)
 {
     AudioBackendClass *b = AUDIO_BACKEND_CLASS(klass);
@@ -939,11 +922,25 @@ static void audio_pa_class_init(ObjectClass *klass, const void *data)

     b->realize = audio_pa_realize;
     k->name = "pa";
-    k->pcm_ops = &qpa_pcm_ops;
     k->max_voices_out = INT_MAX;
     k->max_voices_in = INT_MAX;
     k->voice_size_out = sizeof(PAVoiceOut);
     k->voice_size_in = sizeof(PAVoiceIn);
+
+    k->init_out = qpa_init_out;
+    k->fini_out = qpa_fini_out;
+    k->write = qpa_write;
+    k->buffer_get_free = qpa_buffer_get_free;
+    k->get_buffer_out = qpa_get_buffer_out;
+    k->put_buffer_out = qpa_put_buffer_out;
+    k->volume_out = qpa_volume_out;
+
+    k->init_in = qpa_init_in;
+    k->fini_in = qpa_fini_in;
+    k->read = qpa_read;
+    k->get_buffer_in = qpa_get_buffer_in;
+    k->put_buffer_in = qpa_put_buffer_in;
+    k->volume_in = qpa_volume_in;
 }

 static const TypeInfo audio_types[] = {
diff --git a/audio/pwaudio.c b/audio/pwaudio.c
index f7f7dfbe0a..7a009a94f3 100644
--- a/audio/pwaudio.c
+++ b/audio/pwaudio.c
@@ -822,23 +822,6 @@ audio_pw_finalize(Object *obj)
     g_clear_pointer(&pw->thread_loop, pw_thread_loop_destroy);
 }

-static struct audio_pcm_ops qpw_pcm_ops = {
-    .init_out = qpw_init_out,
-    .fini_out = qpw_fini_out,
-    .write = qpw_write,
-    .buffer_get_free = qpw_buffer_get_free,
-    .run_buffer_out = audio_generic_run_buffer_out,
-    .enable_out = qpw_enable_out,
-    .volume_out = qpw_volume_out,
-    .volume_in = qpw_volume_in,
-
-    .init_in = qpw_init_in,
-    .fini_in = qpw_fini_in,
-    .read = qpw_read,
-    .run_buffer_in = audio_generic_run_buffer_in,
-    .enable_in = qpw_enable_in
-};
-
 static void audio_pw_class_init(ObjectClass *klass, const void *data)
 {
     AudioBackendClass *b = AUDIO_BACKEND_CLASS(klass);
@@ -848,11 +831,25 @@ static void audio_pw_class_init(ObjectClass *klass, const void *data)

     b->realize = audio_pw_realize;
     k->name = "pipewire";
-    k->pcm_ops = &qpw_pcm_ops;
     k->max_voices_out = INT_MAX;
     k->max_voices_in = INT_MAX;
     k->voice_size_out = sizeof(PWVoiceOut);
     k->voice_size_in = sizeof(PWVoiceIn);
+
+    k->init_out = qpw_init_out;
+    k->fini_out = qpw_fini_out;
+    k->write = qpw_write;
+    k->buffer_get_free = qpw_buffer_get_free;
+    k->run_buffer_out = audio_generic_run_buffer_out;
+    k->enable_out = qpw_enable_out;
+    k->volume_out = qpw_volume_out;
+
+    k->init_in = qpw_init_in;
+    k->fini_in = qpw_fini_in;
+    k->read = qpw_read;
+    k->run_buffer_in = audio_generic_run_buffer_in;
+    k->enable_in = qpw_enable_in;
+    k->volume_in = qpw_volume_in;
 }

 static const TypeInfo audio_types[] = {
diff --git a/audio/sdlaudio.c b/audio/sdlaudio.c
index 62f7ac8d76..d974d7eac4 100644
--- a/audio/sdlaudio.c
+++ b/audio/sdlaudio.c
@@ -468,29 +468,6 @@ static void audio_sdl_finalize(Object *obj)
     SDL_QuitSubSystem(SDL_INIT_AUDIO);
 }

-static struct audio_pcm_ops sdl_pcm_ops = {
-    .init_out = sdl_init_out,
-    .fini_out = sdl_fini_out,
-  /* wrapper for audio_generic_write */
-    .write    = sdl_write,
-  /* wrapper for audio_generic_buffer_get_free */
-    .buffer_get_free = sdl_buffer_get_free,
-  /* wrapper for audio_generic_get_buffer_out */
-    .get_buffer_out = sdl_get_buffer_out,
-  /* wrapper for audio_generic_put_buffer_out */
-    .put_buffer_out = sdl_put_buffer_out,
-    .enable_out = sdl_enable_out,
-    .init_in = sdl_init_in,
-    .fini_in = sdl_fini_in,
-  /* wrapper for audio_generic_read */
-    .read = sdl_read,
-  /* wrapper for audio_generic_get_buffer_in */
-    .get_buffer_in = sdl_get_buffer_in,
-  /* wrapper for audio_generic_put_buffer_in */
-    .put_buffer_in = sdl_put_buffer_in,
-    .enable_in = sdl_enable_in,
-};
-
 static void audio_sdl_class_init(ObjectClass *klass, const void *data)
 {
     AudioBackendClass *b = AUDIO_BACKEND_CLASS(klass);
@@ -500,11 +477,32 @@ static void audio_sdl_class_init(ObjectClass *klass, const void *data)

     b->realize = audio_sdl_realize;
     k->name = "sdl";
-    k->pcm_ops = &sdl_pcm_ops;
     k->max_voices_out = INT_MAX;
     k->max_voices_in = INT_MAX;
     k->voice_size_out = sizeof(SDLVoiceOut);
     k->voice_size_in = sizeof(SDLVoiceIn);
+
+    k->init_out = sdl_init_out;
+    k->fini_out = sdl_fini_out;
+    /* wrapper for audio_generic_write */
+    k->write = sdl_write;
+    /* wrapper for audio_generic_buffer_get_free */
+    k->buffer_get_free = sdl_buffer_get_free;
+    /* wrapper for audio_generic_get_buffer_out */
+    k->get_buffer_out = sdl_get_buffer_out;
+    /* wrapper for audio_generic_put_buffer_out */
+    k->put_buffer_out = sdl_put_buffer_out;
+    k->enable_out = sdl_enable_out;
+
+    k->init_in = sdl_init_in;
+    k->fini_in = sdl_fini_in;
+    /* wrapper for audio_generic_read */
+    k->read = sdl_read;
+    /* wrapper for audio_generic_get_buffer_in */
+    k->get_buffer_in = sdl_get_buffer_in;
+    /* wrapper for audio_generic_put_buffer_in */
+    k->put_buffer_in = sdl_put_buffer_in;
+    k->enable_in = sdl_enable_in;
 }

 static const TypeInfo audio_types[] = {
diff --git a/audio/sndioaudio.c b/audio/sndioaudio.c
index 5cd6250775..21f43836fd 100644
--- a/audio/sndioaudio.c
+++ b/audio/sndioaudio.c
@@ -527,32 +527,30 @@ static void sndio_fini_in(HWVoiceIn *hw)
     sndio_fini(self);
 }

-static struct audio_pcm_ops sndio_pcm_ops = {
-    .init_out        = sndio_init_out,
-    .fini_out        = sndio_fini_out,
-    .enable_out      = sndio_enable_out,
-    .write           = audio_generic_write,
-    .buffer_get_free = sndio_buffer_get_free,
-    .get_buffer_out  = sndio_get_buffer_out,
-    .put_buffer_out  = sndio_put_buffer_out,
-    .init_in         = sndio_init_in,
-    .fini_in         = sndio_fini_in,
-    .read            = audio_generic_read,
-    .enable_in       = sndio_enable_in,
-    .get_buffer_in   = sndio_get_buffer_in,
-    .put_buffer_in   = sndio_put_buffer_in,
-};
-
 static void audio_sndio_class_init(ObjectClass *klass, const void *data)
 {
     AudioMixengBackendClass *k = AUDIO_MIXENG_BACKEND_CLASS(klass);

     k->name = "sndio";
-    k->pcm_ops = &sndio_pcm_ops;
     k->max_voices_out = INT_MAX;
     k->max_voices_in = INT_MAX;
     k->voice_size_out = sizeof(SndioVoice);
     k->voice_size_in = sizeof(SndioVoice);
+
+    k->init_out = sndio_init_out;
+    k->fini_out = sndio_fini_out;
+    k->write = audio_generic_write;
+    k->buffer_get_free = sndio_buffer_get_free;
+    k->get_buffer_out = sndio_get_buffer_out;
+    k->put_buffer_out = sndio_put_buffer_out;
+    k->enable_out = sndio_enable_out;
+
+    k->init_in = sndio_init_in;
+    k->fini_in = sndio_fini_in;
+    k->read = audio_generic_read;
+    k->get_buffer_in = sndio_get_buffer_in;
+    k->put_buffer_in = sndio_put_buffer_in;
+    k->enable_in = sndio_enable_in;
 }

 static const TypeInfo audio_types[] = {
diff --git a/audio/spiceaudio.c b/audio/spiceaudio.c
index 995e0f6faa..0d188e974d 100644
--- a/audio/spiceaudio.c
+++ b/audio/spiceaudio.c
@@ -296,29 +296,6 @@ static void line_in_volume(HWVoiceIn *hw, Volume *vol)
 }
 #endif

-static struct audio_pcm_ops audio_callbacks = {
-    .init_out = line_out_init,
-    .fini_out = line_out_fini,
-    .write    = audio_generic_write,
-    .buffer_get_free = line_out_get_free,
-    .get_buffer_out = line_out_get_buffer,
-    .put_buffer_out = line_out_put_buffer,
-    .enable_out = line_out_enable,
-#if (SPICE_INTERFACE_PLAYBACK_MAJOR >= 1) && \
-        (SPICE_INTERFACE_PLAYBACK_MINOR >= 2)
-    .volume_out = line_out_volume,
-#endif
-
-    .init_in  = line_in_init,
-    .fini_in  = line_in_fini,
-    .read     = line_in_read,
-    .run_buffer_in = audio_generic_run_buffer_in,
-    .enable_in = line_in_enable,
-#if ((SPICE_INTERFACE_RECORD_MAJOR >= 2) && (SPICE_INTERFACE_RECORD_MINOR >= 2))
-    .volume_in = line_in_volume,
-#endif
-};
-
 static void audio_spice_class_init(ObjectClass *klass, const void *data)
 {
     AudioBackendClass *b = AUDIO_BACKEND_CLASS(klass);
@@ -328,11 +305,31 @@ static void audio_spice_class_init(ObjectClass *klass, const void *data)

     b->realize = spice_audio_realize;
     k->name = "spice";
-    k->pcm_ops = &audio_callbacks;
     k->max_voices_out = 1;
     k->max_voices_in = 1;
     k->voice_size_out = sizeof(SpiceVoiceOut);
     k->voice_size_in = sizeof(SpiceVoiceIn);
+
+    k->init_out = line_out_init;
+    k->fini_out = line_out_fini;
+    k->write = audio_generic_write;
+    k->buffer_get_free = line_out_get_free;
+    k->get_buffer_out = line_out_get_buffer;
+    k->put_buffer_out = line_out_put_buffer;
+    k->enable_out = line_out_enable;
+#if (SPICE_INTERFACE_PLAYBACK_MAJOR >= 1) && \
+        (SPICE_INTERFACE_PLAYBACK_MINOR >= 2)
+    k->volume_out = line_out_volume;
+#endif
+
+    k->init_in = line_in_init;
+    k->fini_in = line_in_fini;
+    k->read = line_in_read;
+    k->run_buffer_in = audio_generic_run_buffer_in;
+    k->enable_in = line_in_enable;
+#if ((SPICE_INTERFACE_RECORD_MAJOR >= 2) && (SPICE_INTERFACE_RECORD_MINOR >= 2))
+    k->volume_in = line_in_volume;
+#endif
 }

 static const TypeInfo audio_types[] = {
diff --git a/audio/wavaudio.c b/audio/wavaudio.c
index 153e50fa0b..ade8fd1d8c 100644
--- a/audio/wavaudio.c
+++ b/audio/wavaudio.c
@@ -190,25 +190,22 @@ static void wav_enable_out(HWVoiceOut *hw, bool enable)
     }
 }

-static struct audio_pcm_ops wav_pcm_ops = {
-    .init_out = wav_init_out,
-    .fini_out = wav_fini_out,
-    .write    = wav_write_out,
-    .buffer_get_free = audio_generic_buffer_get_free,
-    .run_buffer_out = audio_generic_run_buffer_out,
-    .enable_out = wav_enable_out,
-};
-
 static void audio_wav_class_init(ObjectClass *klass, const void *data)
 {
     AudioMixengBackendClass *k = AUDIO_MIXENG_BACKEND_CLASS(klass);

     k->name = "wav";
-    k->pcm_ops = &wav_pcm_ops;
     k->max_voices_out = 1;
     k->max_voices_in = 0;
     k->voice_size_out = sizeof(WAVVoiceOut);
     k->voice_size_in = 0;
+
+    k->init_out = wav_init_out;
+    k->fini_out = wav_fini_out;
+    k->write = wav_write_out;
+    k->buffer_get_free = audio_generic_buffer_get_free;
+    k->run_buffer_out = audio_generic_run_buffer_out;
+    k->enable_out = wav_enable_out;
 }

 static const TypeInfo audio_types[] = {