It is now possible to control absolute volume of remote volume renderer
device via dbus and also get notifications if the volume changes.
---
Makefile.plugins | 2 +-
profiles/audio/transport.c | 37 +++++++++++++++++++------
profiles/audio/vcp.c | 57 ++++++++++++++++++++++++++++++++++++--
profiles/audio/vcp.h | 12 ++++++++
4 files changed, 95 insertions(+), 13 deletions(-)
create mode 100644 profiles/audio/vcp.h
diff --git a/Makefile.plugins b/Makefile.plugins
index 97335d643..81cf3155a 100644
--- a/Makefile.plugins
+++ b/Makefile.plugins
@@ -128,7 +128,7 @@ endif
if VCP
builtin_modules += vcp
-builtin_sources += profiles/audio/vcp.c
+builtin_sources += profiles/audio/vcp.h profiles/audio/vcp.c
endif
if MICP
diff --git a/profiles/audio/transport.c b/profiles/audio/transport.c
index a4198d23a..eff95a7c2 100644
--- a/profiles/audio/transport.c
+++ b/profiles/audio/transport.c
@@ -55,6 +55,7 @@
#include "media.h"
#include "transport.h"
#include "bass.h"
+#include "vcp.h"
#define MEDIA_TRANSPORT_INTERFACE "org.bluez.MediaTransport1"
@@ -1420,6 +1421,7 @@ static const GDBusPropertyTable transport_bap_uc_properties[] = {
{ "Location", "u", get_location },
{ "Metadata", "ay", get_metadata },
{ "Links", "ao", get_links, NULL, links_exists },
+ { "Volume", "q", get_volume, set_volume, volume_exists },
{ }
};
@@ -2188,6 +2190,17 @@ static void bap_connecting(struct bt_bap_stream *stream, bool state, int fd,
bap_update_links(transport);
}
+static int8_t transport_bap_get_volume(struct media_transport *transport)
+{
+ return bt_audio_vcp_get_volume(transport->device);
+}
+
+static int transport_bap_set_volume(struct media_transport *transport,
+ int8_t volume)
+{
+ return bt_audio_vcp_set_volume(transport->device, volume) ? 0 : -EIO;
+}
+
static void transport_bap_destroy(void *data)
{
struct bap_transport *bap = data;
@@ -2411,7 +2424,8 @@ static void *transport_asha_init(struct media_transport *transport, void *data)
transport_bap_init, \
transport_bap_resume, transport_bap_suspend, \
transport_bap_cancel, _set_state, \
- transport_bap_get_stream, NULL, NULL, NULL, \
+ transport_bap_get_stream, transport_bap_get_volume, \
+ transport_bap_set_volume, NULL, \
_update_links, transport_bap_destroy)
#define BAP_UC_OPS(_uuid) \
@@ -2573,17 +2587,18 @@ struct btd_device *media_transport_get_dev(struct media_transport *transport)
void media_transport_update_volume(struct media_transport *transport,
int8_t volume)
{
- struct a2dp_transport *a2dp = transport->data;
-
if (volume < 0)
return;
- /* Check if volume really changed */
- if (a2dp->volume == volume)
- return;
+ if (media_endpoint_get_sep(transport->endpoint)) {
+ struct a2dp_transport *a2dp = transport->data;
- a2dp->volume = volume;
+ /* Check if volume really changed */
+ if (a2dp->volume == volume)
+ return;
+ a2dp->volume = volume;
+ }
g_dbus_emit_property_changed(btd_get_dbus_connection(),
transport->path,
MEDIA_TRANSPORT_INTERFACE, "Volume");
@@ -2628,11 +2643,15 @@ void media_transport_update_device_volume(struct btd_device *dev,
/* Attempt to locate the transport to set its volume */
for (l = transports; l; l = l->next) {
struct media_transport *transport = l->data;
+ const char *uuid = media_endpoint_get_uuid(transport->endpoint);
if (transport->device != dev)
continue;
- /* Volume is A2DP only */
- if (media_endpoint_get_sep(transport->endpoint)) {
+ /* Volume is A2DP and BAP only */
+ if (media_endpoint_get_sep(transport->endpoint) ||
+ strcasecmp(uuid, PAC_SINK_UUID) ||
+ strcasecmp(uuid, PAC_SOURCE_UUID) ||
+ strcasecmp(uuid, BAA_SERVICE_UUID)) {
media_transport_update_volume(transport, volume);
break;
}
diff --git a/profiles/audio/vcp.c b/profiles/audio/vcp.c
index 175275f2e..cc6f352c1 100644
--- a/profiles/audio/vcp.c
+++ b/profiles/audio/vcp.c
@@ -51,6 +51,9 @@
#include "src/log.h"
#include "src/error.h"
+#include "vcp.h"
+#include "transport.h"
+
#define VCS_UUID_STR "00001844-0000-1000-8000-00805f9b34fb"
#define MEDIA_ENDPOINT_INTERFACE "org.bluez.MediaEndpoint1"
@@ -83,6 +86,33 @@ static struct vcp_data *vcp_data_new(struct btd_device *device)
return data;
}
+static bool match_data(const void *data, const void *match_data)
+{
+ const struct vcp_data *vdata = data;
+ const struct bt_vcp *vcp = match_data;
+
+ return vdata->vcp == vcp;
+}
+
+static int8_t scale_volume_vcp2transport(uint8_t volume)
+{
+ /* Transport has volume range 0-127, VCP has range 0-255 */
+ return volume / 2;
+}
+
+static uint8_t scale_volume_transport2vcp(int8_t volume)
+{
+ return volume * 2;
+}
+
+static void vcp_volume_changed(struct bt_vcp *vcp, uint8_t volume)
+{
+ struct vcp_data *data = queue_find(sessions, match_data, vcp);
+
+ if (data)
+ media_transport_update_device_volume(data->device, scale_volume_vcp2transport(volume));
+}
+
static void vcp_data_add(struct vcp_data *data)
{
DBG("data %p", data);
@@ -93,6 +123,7 @@ static void vcp_data_add(struct vcp_data *data)
}
bt_vcp_set_debug(data->vcp, vcp_debug, NULL, NULL);
+ bt_vcp_set_volume_callback(data->vcp, vcp_volume_changed);
if (!sessions)
sessions = queue_new();
@@ -103,12 +134,12 @@ static void vcp_data_add(struct vcp_data *data)
btd_service_set_user_data(data->service, data);
}
-static bool match_data(const void *data, const void *match_data)
+static bool match_device(const void *data, const void *match_data)
{
const struct vcp_data *vdata = data;
- const struct bt_vcp *vcp = match_data;
+ const struct btd_device *device = match_data;
- return vdata->vcp == vcp;
+ return vdata->device == device;
}
static void vcp_data_free(struct vcp_data *data)
@@ -137,6 +168,26 @@ static void vcp_data_remove(struct vcp_data *data)
}
}
+int8_t bt_audio_vcp_get_volume(struct btd_device *device)
+{
+ struct vcp_data *data = queue_find(sessions, match_device, device);
+
+ if (data)
+ return scale_volume_vcp2transport(bt_vcp_get_volume(data->vcp));
+
+ return 0;
+}
+
+bool bt_audio_vcp_set_volume(struct btd_device *device, int8_t volume)
+{
+ struct vcp_data *data = queue_find(sessions, match_device, device);
+
+ if (data)
+ return bt_vcp_set_volume(data->vcp, scale_volume_transport2vcp(volume));
+
+ return FALSE;
+}
+
static void vcp_detached(struct bt_vcp *vcp, void *user_data)
{
struct vcp_data *data;
diff --git a/profiles/audio/vcp.h b/profiles/audio/vcp.h
new file mode 100644
index 000000000..f313cd96a
--- /dev/null
+++ b/profiles/audio/vcp.h
@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *
+ * BlueZ - Bluetooth protocol stack for Linux
+ *
+ * Copyright (C) 2024 StreamUnlimited Engineering GmbH
+ *
+ *
+ */
+
+int8_t bt_audio_vcp_get_volume(struct btd_device *device);
+bool bt_audio_vcp_set_volume(struct btd_device *device, int8_t volume);
--
2.34.1
