From 5c4743441e2a022a093024b15aedfa60fb1e1e3c Mon Sep 17 00:00:00 2001
From: Max Kellermann <max.kellermann@gmail.com>
Date: Thu, 18 Aug 2022 14:08:30 +0200
Subject: [PATCH 1/3] mixer/All: use Mixer::IsPlugin()

---
 src/mixer/MixerAll.cxx | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/mixer/MixerAll.cxx b/src/mixer/MixerAll.cxx
index 302a06160..8cf8295e0 100644
--- a/src/mixer/MixerAll.cxx
+++ b/src/mixer/MixerAll.cxx
@@ -188,8 +188,8 @@ MultipleOutputs::SetSoftwareVolume(unsigned volume) noexcept
 		auto *mixer = ao->GetMixer();
 
 		if (mixer != nullptr &&
-		    (&mixer->plugin == &software_mixer_plugin ||
-		     &mixer->plugin == &null_mixer_plugin))
+		    (mixer->IsPlugin(software_mixer_plugin) ||
+		     mixer->IsPlugin(null_mixer_plugin)))
 			mixer_set_volume(mixer, volume);
 	}
 }

From 2b8f1170a64c33be35d45b79d6c8c3e4eebddf60 Mon Sep 17 00:00:00 2001
From: Max Kellermann <max.kellermann@gmail.com>
Date: Thu, 18 Aug 2022 14:33:19 +0200
Subject: [PATCH 2/3] mixer/Control: use Mixer::IsGlobal()

---
 src/mixer/MixerControl.cxx | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/mixer/MixerControl.cxx b/src/mixer/MixerControl.cxx
index 51ea759c1..2cc46e501 100644
--- a/src/mixer/MixerControl.cxx
+++ b/src/mixer/MixerControl.cxx
@@ -92,7 +92,7 @@ mixer_close(Mixer *mixer)
 void
 mixer_auto_close(Mixer *mixer)
 {
-	if (!mixer->plugin.global)
+	if (!mixer->IsGlobal())
 		mixer_close(mixer);
 }
 
@@ -103,7 +103,7 @@ mixer_get_volume(Mixer *mixer)
 
 	assert(mixer != nullptr);
 
-	if (mixer->plugin.global && !mixer->failure)
+	if (mixer->IsGlobal() && !mixer->failure)
 		mixer_open(mixer);
 
 	const std::scoped_lock<Mutex> protect(mixer->mutex);
@@ -128,7 +128,7 @@ mixer_set_volume(Mixer *mixer, unsigned volume)
 	assert(mixer != nullptr);
 	assert(volume <= 100);
 
-	if (mixer->plugin.global && !mixer->failure)
+	if (mixer->IsGlobal() && !mixer->failure)
 		mixer_open(mixer);
 
 	const std::scoped_lock<Mutex> protect(mixer->mutex);

From e2d4654e2010f9dbc2f5798319e6170a5da033f1 Mon Sep 17 00:00:00 2001
From: Max Kellermann <max.kellermann@gmail.com>
Date: Thu, 18 Aug 2022 14:36:30 +0200
Subject: [PATCH 3/3] filter/ReplayGain: invoke the MixerListener after volume
 change

This ensures that Partition::OnMixerVolumeChanged() invokes
MixerMemento::InvalidateHardwareVolume(), clearing the cached volume
level.

Closes https://github.com/MusicPlayerDaemon/MPD/issues/1526
---
 NEWS                                          |  2 ++
 src/filter/plugins/ReplayGainFilterPlugin.cxx | 10 +++++++---
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/NEWS b/NEWS
index 23f2c41ff..4c36c9b5d 100644
--- a/NEWS
+++ b/NEWS
@@ -3,6 +3,8 @@ ver 0.23.9 (not yet released)
   - cdio_paranoia: add options "mode" and "skip"
 * decoder
   - ffmpeg: support FFmpeg 5.1
+* filter
+  - replay gain: fix delayed volume display with handler=mixer
 * output
   - pipewire: set app icon
 * fix bogus volume levels with multiple partitions
diff --git a/src/filter/plugins/ReplayGainFilterPlugin.cxx b/src/filter/plugins/ReplayGainFilterPlugin.cxx
index 3c2f6b351..e89f4af69 100644
--- a/src/filter/plugins/ReplayGainFilterPlugin.cxx
+++ b/src/filter/plugins/ReplayGainFilterPlugin.cxx
@@ -23,6 +23,8 @@
 #include "ReplayGainInfo.hxx"
 #include "ReplayGainConfig.hxx"
 #include "mixer/MixerControl.hxx"
+#include "mixer/MixerInternal.hxx"
+#include "mixer/Listener.hxx"
 #include "pcm/AudioFormat.hxx"
 #include "pcm/Volume.hxx"
 #include "util/ConstBuffer.hxx"
@@ -171,9 +173,11 @@ ReplayGainFilter::Update()
 		try {
 			mixer_set_volume(mixer, _volume);
 
-			/* TODO: emit this idle event only for the
-			   current partition */
-			idle_add(IDLE_MIXER);
+			/* invoke the mixer's listener manually, just
+			   in case the mixer implementation didn't do
+			   that already (this depends on the
+			   implementation) */
+			mixer->listener.OnMixerVolumeChanged(*mixer, _volume);
 		} catch (...) {
 			LogError(std::current_exception(),
 				 "Failed to update hardware mixer");