audiomixer: Add gain controls

- Add Equalizer gain controls.
- Add a simple app to test the controls.

Bug-AGL: SPEC-4931
Change-Id: Ib33eb0e829747c401861e99acd67291462ec6a97
Signed-off-by: Ashok Sidipotu <ashok.sidipotu@collabora.com>

1 files changed, 226 insertions, 7 deletions

diff --git a/src/audiomixer.c b/src/audiomixer.c
index a40a38e..0351738 100644
--- a/src/audiomixer.c
+++ b/src/audiomixer.c
@@ -7,6 +7,7 @@
 
 #include "audiomixer.h"
 #include <wp/wp.h>
+#include <math.h>
 #include <pipewire/pipewire.h>
 
 struct audiomixer
@@ -22,6 +23,8 @@ struct audiomixer
 
 	gint initialized;
 	WpObjectManager *om;
+	WpObjectManager *eq_om;
+	WpPipewireObject *eq_node;
 	WpPlugin *default_nodes_api;
 	WpPlugin *mixer_api;
 
@@ -47,6 +50,11 @@ struct action
 			guint32 id;
 			gboolean mute;
 		} change_mute;
+		struct {
+			guint32 id;
+			gchar *control;
+			gfloat gain;
+		} change_gain;
 	};
 };
 
@@ -60,6 +68,86 @@ get_mixer_controls (struct audiomixer * self, guint32 node_id, gdouble * vol, gb
 		g_variant_lookup (v, "mute", "b", mute);
 }
 
+static gboolean
+get_gain (struct audiomixer *self, const char *name, gfloat *gain)
+{
+	g_autoptr (WpIterator) it = NULL;
+	g_auto (GValue) val = G_VALUE_INIT;
+	gchar param_name[20];
+	gboolean ret = FALSE;
+
+	snprintf (param_name, sizeof (param_name), "%s:%s", name, "Gain");
+
+	it = wp_pipewire_object_enum_params_sync (self->eq_node, "Props", NULL);
+
+	for (; it && wp_iterator_next (it, &val); g_value_unset (&val)) {
+		WpSpaPod *props = g_value_get_boxed (&val);
+		WpSpaPod *params = NULL;
+		g_autoptr (WpIterator) it1 = NULL;
+		g_auto (GValue) val1 = G_VALUE_INIT;
+		gboolean param_found = FALSE;
+
+		if (!wp_spa_pod_get_object (props, NULL, "params", "T", &params, NULL))
+			continue;
+
+		if (!wp_spa_pod_is_struct (params))
+			continue;
+
+		/* iterate through the params structure */
+		for (it1 = wp_spa_pod_new_iterator (params);
+				it1 && wp_iterator_next (it1, &val1);
+				g_value_unset (&val1)) {
+
+			WpSpaPod *sparams = g_value_get_boxed (&val1);
+
+			if (sparams && wp_spa_pod_is_string (sparams)) {
+				const gchar *token = NULL;
+				wp_spa_pod_get_string (sparams, &token);
+					if (g_str_equal (token, param_name)) {
+						/* read the next field to get the gain value */
+						param_found = TRUE;
+						continue;
+					}
+			}
+			else if (sparams && param_found && wp_spa_pod_is_float (sparams)) {
+				if (wp_spa_pod_get_float (sparams, gain)) {
+					g_debug ("gain for control(%s) is %f", param_name, *gain);
+					ret = TRUE;
+					break;
+				}
+			}
+
+		}
+
+		if (param_found)
+			break;
+
+	}
+	return ret;
+}
+
+static void
+add_eq_control (struct audiomixer *self, const char *name, guint32 node_id)
+{
+	struct mixer_control_impl *mixctl = NULL;
+	gfloat gain = 0.0;
+
+	/* get current gain */
+	if (!get_gain (self, name, &gain)) {
+		g_warning ("failed to get the gain value");
+		return;
+	}
+
+	/* create the control */
+	mixctl = g_new0 (struct mixer_control_impl, 1);
+	snprintf (mixctl->pub.name, sizeof (mixctl->pub.name), "%s", name);
+	mixctl->pub.gain = gain;
+	mixctl->node_id = node_id;
+	g_ptr_array_add (self->mixer_controls, mixctl);
+
+	g_debug ("added (%s) eq control and its gain is %f", mixctl->pub.name, gain);
+}
+
 static void
 add_control (struct audiomixer *self, const char *name, guint32 node_id)
 {
@@ -69,7 +157,8 @@ add_control (struct audiomixer *self, const char *name, guint32 node_id)
 
 	/* get current values */
 	if (!get_mixer_controls (self, node_id, &volume, &mute)) {
-		g_warning ("failed to get object controls when populating controls");
+		g_warning ("failed to get object controls when populating controls for %s",
+			name);
 		return;
 	}
 
@@ -81,7 +170,7 @@ add_control (struct audiomixer *self, const char *name, guint32 node_id)
 	mixctl->node_id = node_id;
 	g_ptr_array_add (self->mixer_controls, mixctl);
 
-	g_debug ("added control %s", mixctl->pub.name);
+	g_debug ("added control %s its volume is %f", mixctl->pub.name, volume);
 }
 
 static void
@@ -154,6 +243,14 @@ rescan_controls (struct audiomixer * self)
 			add_control (self, name, id);
 	}
 
+	if (self->eq_node) {
+		id = wp_proxy_get_bound_id (WP_PROXY (self->eq_node));
+		if (id != 0 && id != (guint32)-1) {
+			add_eq_control (self, "bass", id);
+			add_eq_control (self, "treble", id);
+		}
+	}
+
 	/* notify subscribers */
 	if (self->events && self->events->controls_changed)
 		self->events->controls_changed (self->events_data);
@@ -169,8 +266,10 @@ on_default_nodes_activated (WpObject * p, GAsyncResult * res, struct audiomixer
 	}
 
 	if (wp_object_get_active_features (WP_OBJECT (self->mixer_api))
-			& WP_PLUGIN_FEATURE_ENABLED)
-		wp_core_install_object_manager (self->core, self->om);
+		& WP_PLUGIN_FEATURE_ENABLED) {
+			wp_core_install_object_manager (self->core, self->eq_om);
+			wp_core_install_object_manager (self->core, self->om);
+	}
 
 	g_signal_connect_swapped (self->default_nodes_api, "changed",
 		(GCallback) rescan_controls, self);
@@ -185,16 +284,73 @@ on_mixer_activated (WpObject * p, GAsyncResult * res, struct audiomixer * self)
 	}
 
 	if (wp_object_get_active_features (WP_OBJECT (self->default_nodes_api))
-			& WP_PLUGIN_FEATURE_ENABLED)
-		wp_core_install_object_manager (self->core, self->om);
+		& WP_PLUGIN_FEATURE_ENABLED) {
+			wp_core_install_object_manager (self->core, self->om);
+			wp_core_install_object_manager (self->core, self->eq_om);
+	}
 
 	g_signal_connect_swapped (self->mixer_api, "changed",
 		(GCallback) volume_changed, self);
 }
 
 static void
-on_core_connected (struct audiomixer * self)
+on_eq_params_changed (WpPipewireObject *obj, const gchar *param_name,
+	struct audiomixer * self)
 {
+	gfloat gain = 0.0;
+	guint32 node_id = wp_proxy_get_bound_id (WP_PROXY (obj));
+
+	if (!g_str_equal (param_name, "Props"))
+		return;
+
+	for (guint i = 0; i < self->mixer_controls->len; i++) {
+		struct mixer_control_impl *ctl;
+		guint change_mask = 0;
+
+		ctl = g_ptr_array_index (self->mixer_controls, i);
+
+		if (ctl->node_id != node_id)
+			continue;
+
+		if (!get_gain (self, ctl->pub.name, &gain)) {
+				g_warning ("failed to get cached gain value");
+				return;
+			}
+
+		if (!(fabs (ctl->pub.gain - gain) < 0.000001)) {
+			/* if gain changed */
+			ctl->pub.gain = gain;
+			change_mask |= MIXER_CONTROL_CHANGE_FLAG_GAIN;
+			if (self->events && self->events->value_changed) {
+				self->events->value_changed (self->events_data, change_mask, &ctl->pub);
+			}
+		}
+
+		break;
+	}
+}
+static void
+on_eq_added (WpObjectManager *om, WpPipewireObject *node,
+	struct audiomixer *self)
+{
+	self->eq_node = node;
+	g_signal_connect (node, "params-changed", G_CALLBACK (on_eq_params_changed),
+		self);
+	rescan_controls (self);
+}
+
+static void
+on_eq_removed (WpObjectManager *om, WpPipewireObject *node, struct audiomixer
+	*self)
+{
+	self->eq_node = NULL;
+	rescan_controls (self);
+}
+
+static void
+on_core_connected (struct audiomixer *self)
+{
+
 	self->om = wp_object_manager_new ();
 	wp_object_manager_add_interest (self->om, WP_TYPE_ENDPOINT,
 		WP_CONSTRAINT_TYPE_PW_GLOBAL_PROPERTY,
@@ -204,6 +360,23 @@ on_core_connected (struct audiomixer * self)
 	g_signal_connect_swapped (self->om, "objects-changed",
 		(GCallback) rescan_controls, self);
 
+	self->eq_node = NULL;
+	self->eq_om = wp_object_manager_new ();
+	/*
+	 * "eq-sink" name matches with the name of sink node loaded by the equalizer
+	 * module present in the config.
+	 */
+	wp_object_manager_add_interest (self->eq_om, WP_TYPE_NODE,
+		WP_CONSTRAINT_TYPE_PW_GLOBAL_PROPERTY, PW_KEY_NODE_NAME, "=s", "eq-sink",
+		WP_CONSTRAINT_TYPE_PW_PROPERTY, PW_KEY_MEDIA_CLASS, "=s", "Audio/Sink",
+		NULL);
+	wp_object_manager_request_object_features (self->eq_om,
+		WP_TYPE_NODE, WP_OBJECT_FEATURES_ALL);
+	g_signal_connect (self->eq_om, "object-added", G_CALLBACK (on_eq_added),
+		self);
+	g_signal_connect (self->eq_om, "object-removed", G_CALLBACK (on_eq_removed),
+		self);
+
 	wp_object_activate (WP_OBJECT (self->default_nodes_api),
 		WP_PLUGIN_FEATURE_ENABLED, NULL,
 		(GAsyncReadyCallback) on_default_nodes_activated, self);
@@ -218,6 +391,7 @@ on_core_disconnected (struct audiomixer * self)
 {
 	g_ptr_array_set_size (self->mixer_controls, 0);
 	g_clear_object (&self->om);
+	g_clear_object (&self->eq_om);
 	g_signal_handlers_disconnect_by_data (self->default_nodes_api, self);
 	g_signal_handlers_disconnect_by_data (self->mixer_api, self);
 	wp_object_deactivate (WP_OBJECT (self->default_nodes_api), WP_PLUGIN_FEATURE_ENABLED);
@@ -461,3 +635,48 @@ audiomixer_change_mute(struct audiomixer *self,
 	wp_core_idle_add (self->core, NULL, (GSourceFunc) do_change_mute, action,
 		g_free);
 }
+
+static gboolean
+do_change_gain (struct action * action)
+{
+	struct audiomixer *self = action->audiomixer;
+	gboolean ret = FALSE;
+	gchar name[20];
+	g_autoptr (WpSpaPodBuilder) s = wp_spa_pod_builder_new_struct ();
+
+	snprintf (name, sizeof (name), "%s:%s", action->change_gain.control, "Gain");
+	wp_spa_pod_builder_add_string (s, name);
+	wp_spa_pod_builder_add_float (s, action->change_gain.gain);
+
+	g_autoptr (WpSpaPod) props =
+		wp_spa_pod_new_object ("Spa:Pod:Object:Param:Props", "Props",
+			"params", "P", wp_spa_pod_builder_end (s), NULL);
+
+	ret = wp_pipewire_object_set_param (self->eq_node, "Props", 0,
+		g_steal_pointer (&props));
+
+	if(!ret)
+		g_warning ("set gain failed");
+
+	return G_SOURCE_REMOVE;
+}
+
+void
+audiomixer_change_gain(struct audiomixer *self,
+	const struct mixer_control *control,
+	float gain)
+{
+	const struct mixer_control_impl *impl = control;
+	struct action * action;
+
+	g_return_if_fail (self->initialized == 1);
+
+	/* schedule the action to run on the audiomixer thread */
+	action = g_new0 (struct action, 1);
+	action->audiomixer = self;
+	action->change_gain.id = impl->node_id;
+	action->change_gain.gain = gain;
+	action->change_gain.control = impl->pub.name;
+	wp_core_idle_add (self->core, NULL, (GSourceFunc) do_change_gain, action,
+		g_free);
+}