From ca0a96fcfb879fcffae8658ce418e8c0c08c1518 Mon Sep 17 00:00:00 2001
From: Arun Raghavan <arunr@valvesoftware.com>
Date: Wed, 4 Feb 2026 16:58:21 -0800
Subject: [PATCH] spa: Add a param for audio volume control flags

Should be usable to signal to clients what volume control capabilities a
device supports.
---
 spa/include/spa/param/audio/volume.h | 29 ++++++++++++++++++++++++++++
 spa/include/spa/param/props-types.h  |  1 +
 spa/include/spa/param/props.h        |  2 ++
 3 files changed, 32 insertions(+)
 create mode 100644 spa/include/spa/param/audio/volume.h

diff --git a/spa/include/spa/param/audio/volume.h b/spa/include/spa/param/audio/volume.h
new file mode 100644
index 000000000..56df18064
--- /dev/null
+++ b/spa/include/spa/param/audio/volume.h
@@ -0,0 +1,29 @@
+/* Simple Plugin API */
+/* SPDX-FileCopyrightText: Copyright © 2026 Arun Raghavan */
+/* SPDX-License-Identifier: MIT */
+
+#ifndef SPA_AUDIO_VOLUME_H
+#define SPA_AUDIO_VOLUME_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/** Flags for volume control capabilities */
+enum spa_audio_volume_control_flags {
+	SPA_AUDIO_VOLUME_CONTROL_NONE = 0,				/**<< No flags */
+	SPA_AUDIO_VOLUME_CONTROL_READ_VOLUME = (1 << 0),		/**<< Volume value can be read */
+	SPA_AUDIO_VOLUME_CONTROL_WRITE_VOLUME_VALUE = (1 << 1),		/**<< Volume value can be set */
+	SPA_AUDIO_VOLUME_CONTROL_WRITE_VOLUME_UPDOWN = (1 << 2),	/**<< Volume value can incremented/decremented */
+	SPA_AUDIO_VOLUME_CONTROL_READ_MUTE = (1 << 3),			/**<< Mute state can be read */
+	SPA_AUDIO_VOLUME_CONTROL_WRITE_MUTE_VALUE = (1 << 4),		/**<< Mute state can be set */
+	SPA_AUDIO_VOLUME_CONTROL_WRITE_MUTE_TOGGLE = (1 << 5),		/**<< Mute state can be toggled */
+	SPA_AUDIO_VOLUME_CONTROL_READ_BALANCE = (1 << 6),		/**<< Per-channel volumes can be read */
+	SPA_AUDIO_VOLUME_CONTROL_WRITE_BALANCE = (1 << 7),		/**<< Per-channel volumes can be set */
+};
+
+#ifdef __cplusplus
+} /* extern "C" */
+#endif
+
+#endif /* SPA_AUDIO_VOLUME_H */
diff --git a/spa/include/spa/param/props-types.h b/spa/include/spa/param/props-types.h
index 0a7c916b8..239770e59 100644
--- a/spa/include/spa/param/props-types.h
+++ b/spa/include/spa/param/props-types.h
@@ -66,6 +66,7 @@ static const struct spa_type_info spa_type_props[] = {
 	{ SPA_PROP_volumeRampTime, SPA_TYPE_Int, SPA_TYPE_INFO_PROPS_BASE "volumeRampTime", NULL },
 	{ SPA_PROP_volumeRampStepTime, SPA_TYPE_Int, SPA_TYPE_INFO_PROPS_BASE "volumeRampStepTime", NULL },
 	{ SPA_PROP_volumeRampScale, SPA_TYPE_Id, SPA_TYPE_INFO_PROPS_BASE "volumeRampScale", spa_type_audio_volume_ramp_scale },
+	{ SPA_PROP_volumeControlFlags, SPA_TYPE_Int, SPA_TYPE_INFO_PROPS_BASE "volumeControlFlags", NULL },
 
 	{ SPA_PROP_brightness, SPA_TYPE_Float, SPA_TYPE_INFO_PROPS_BASE "brightness", NULL },
 	{ SPA_PROP_contrast, SPA_TYPE_Float, SPA_TYPE_INFO_PROPS_BASE "contrast", NULL },
diff --git a/spa/include/spa/param/props.h b/spa/include/spa/param/props.h
index 48338b870..94862ea88 100644
--- a/spa/include/spa/param/props.h
+++ b/spa/include/spa/param/props.h
@@ -98,6 +98,8 @@ enum spa_prop {
 						  *  to ramp the */
 	SPA_PROP_volumeRampScale,		/**< the scale or graph to used to ramp the
 						  *  volume */
+	SPA_PROP_volumeControlFlags,		/**< Available volume control features
+						  * (Id enum spa_audio_volume_control_flags) */
 
 	SPA_PROP_START_Video	= 0x20000,	/**< video related properties */
 	SPA_PROP_brightness,