Fix volume switch for controls with a virtual/simulated mute switch.

CCBUGS: 309334

backends/mixer_alsa9.cpp

@@ -717,7 +717,17 @@ Mixer_ALSA::readVolumeFromHW( const QString& id, shared_ptr<MixDevice> md )
 
     vol = Volume::MNONE;
     // --- playback volume
-    if ( snd_mixer_selem_has_playback_volume( elem ) ) {
+    if ( snd_mixer_selem_has_playback_volume( elem ) )
+    {
+    	if ( md->isVirtuallyMuted() )
+    	{
+    		// Special code path for controls w/o physical mute switch. Doing it in all backends is not perfect,
+    		// but it saves a lot of code and removes a lot of complexity in the Volume and MixDevice classes.
+
+    		// Don't feed back the actual 0 volume back from the device to KMix. Just do nothing!
+    	}
+    	else
+    	{
         foreach (VolumeChannel vc, volumePlayback.getVolumes() )
         {
                int ret = 0;
@@ -739,6 +749,7 @@ Mixer_ALSA::readVolumeFromHW( const QString& id, shared_ptr<MixDevice> md )
 		volumePlayback.setVolume( vc.chid, vol);
               //if (id== "Master:0" || id== "PCM:0" ) { kDebug() << "volumePlayback control=" << id << ", chid=" << i << ", vol=" << vol; }
        }
+    	}
     } // has playback volume
 
     // --- playback switch
@@ -811,9 +822,32 @@ Mixer_ALSA::writeVolumeToHW( const QString& id, shared_ptr<MixDevice> md )
         return 0;
     }
 
+
+    // --- playback switch
+    bool hasPlaybackSwitch = snd_mixer_selem_has_playback_switch( elem ) || snd_mixer_selem_has_common_switch  ( elem );
+	if (hasPlaybackSwitch)
+	{
+		int sw = 0;
+		if (!md->isMuted())
+			sw = !sw; // invert all bits
+		snd_mixer_selem_set_playback_switch_all(elem, sw);
+	}
+
+
     // --- playback volume
     if ( snd_mixer_selem_has_playback_volume( elem ) )
     {
+    	kDebug() << "phys=" << md->hasPhysicalMuteSwitch() << ", muted=" << md->isMuted();
+    	if ( md->isVirtuallyMuted() )
+    	{
+    		// Special code path for controls w/o physical mute switch. Doing it in all backends is not perfect,
+    		// but it saves a lot of code and removes a lot of complexity in the Volume and MixDevice classes.
+    		int ret = snd_mixer_selem_set_playback_volume_all( elem, (long)0);
+            if ( ret != 0 )
+          	  kDebug() << "writeVolumeToHW(" << devnum << ") [set_playback_volume] failed, errno=" << ret;
+    	}
+    	else
+    	{
       foreach (VolumeChannel vc, volumePlayback.getVolumes() )
       {
                int ret = 0;
@@ -830,20 +864,13 @@ Mixer_ALSA::writeVolumeToHW( const QString& id, shared_ptr<MixDevice> md )
                    case Volume::REARSIDERIGHT: ret = snd_mixer_selem_set_playback_volume( elem, SND_MIXER_SCHN_SIDE_RIGHT  , vc.volume); break;
                    default: kDebug() << "FATAL: Unknown channel type for playback << " << vc.chid << " ... please report this";  break;
               }
-              if ( ret != 0 ) kDebug() << "writeVolumeToHW(" << devnum << ") [set_playback_volume] failed, errno=" << ret;
+              if ( ret != 0 )
+            	  kDebug() << "writeVolumeToHW(" << devnum << ") [set_playback_volume] failed, errno=" << ret;
               //if (id== "Master:0" || id== "PCM:0" ) { kDebug() << "volumePlayback control=" << id << ", chid=" << vc.chid << ", vol=" << vc.volume; }
           }
+    	}
     } // has playback volume
 
-    // --- playback switch
-    if ( snd_mixer_selem_has_playback_switch( elem ) ||
-         snd_mixer_selem_has_common_switch  ( elem )   )
-    {
-        int sw = 0;
-        if ( ! md->isMuted() )
-            sw = !sw; // invert all bits
-        snd_mixer_selem_set_playback_switch_all(elem, sw);
-    }
 
 
     // --- capture volume

core/mixdevice.cpp

@@ -240,6 +240,13 @@ const QString MixDevice::dbusPath() {
 
 
 bool MixDevice::isMuted()                  { return ! _playbackVolume.isSwitchActivated(); }
+/**
+ * Returns whether this MixDevice is virtually muted. Only MixDevice objects w/o a physical switch can be muted virtually.
+ */
+bool MixDevice::isVirtuallyMuted()
+{
+	return !hasPhysicalMuteSwitch() && isMuted();
+}
 void MixDevice::setMuted(bool mute)        { _playbackVolume.setSwitch(!mute); }
 void MixDevice::toggleMute()               { setMuted( !_playbackVolume.isSwitchActivated()); }
 bool MixDevice::hasMuteSwitch()            { return playbackVolume().hasVolume() || playbackVolume().hasSwitch(); }

core/mixdevice.h

@@ -163,6 +163,7 @@ public:
    // is an abstract concept. It places no interpretation on the meaning of the switch (e.g. does "switch set" mean
    // "mute on", or does it mean "playback on", or "Capture active", or ...
    virtual bool isMuted();
+   virtual bool isVirtuallyMuted();
    virtual void setMuted(bool value);
    virtual bool hasMuteSwitch();
    virtual void toggleMute();

core/volume.cpp

@@ -107,7 +107,10 @@ void Volume::init( ChannelMask chmask, long maxVolume, long minVolume, bool hasS
 	_hasSwitch       = hasSwitch;
 	_isCapture       = isCapture;
 	//_muted           = false;
-	_switchActivated = false;
+	// Presume that the switch is active. This will always work:
+	// a) Physical switches will be updated after start from the hardware.
+	// b) Emulated virtual/switches will not receive updates from the hardware, so they shouldn't disable the channels.
+	_switchActivated = true;
 	disallowSwitchDisallowRead = false;
 }
 

core/volume.h

@@ -115,26 +115,18 @@ friend class MixDevice;
     
     bool hasSwitch() const
     {
-      if (isCapture())
-      {
-	return _hasSwitch;
-      }
-      else
-      {
-		if ( disallowSwitchDisallowRead )
-	{
-	  kError() << "hasSwitch() must only be called for capture volumes. I will crash now to retreieve a stacktrace!!!";
-	  QObject* obj = 0;
-	  obj->blockSignals(true);
-	  return _hasSwitch;
-	}
-	else
-	  kDebug() << "Allow playback switch read once";
-      }
-	return _hasSwitch;
+    	return _hasSwitch;
     };
     bool hasVolume() const          { return (_maxVolume != _minVolume); }
-    bool isCapture() const          { return _isCapture; } // -<- Query thsi, to find out whether this is a capture or  a playback volume
+    /**
+     * Returns whether this is a playback or capture volume.
+     *
+     * @return true, if it is a capture volume
+     */
+    bool isCapture() const
+    {
+    	return _isCapture;
+    }
     
    // Some playback switches control playback, and some are special.
    // ALSA doesn't differentiate between playback, OnOff and special, so users can add this information in the profile.
@@ -167,24 +159,7 @@ protected:
    bool isSwitchActivated() const  // TODO rename to isActive()
    {
 	   return _switchActivated;
-
-      if (isCapture())
-      {
-	return _switchActivated && hasSwitch();
-      }
-      else
-      {
-	if ( disallowSwitchDisallowRead )
-	{
-	  kError() << "isSwitchActivated() must only be called for capture volumes. I will crash now to retreieve a stacktrace!!!";
-	  QObject* obj = 0;
-	  obj->blockSignals(true);
-	  return _switchActivated && hasSwitch();
-	}
-      }
-	  return _switchActivated && hasSwitch();
-
-  };
+   };
 
 
 private: