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* [Bluez PATCH v4 1/2] audio/transport: change volume to 8bit
@ 2020-07-23  6:22 Archie Pusaka
  2020-07-23  6:22 ` [Bluez PATCH v4 2/2] audio/transport: supply volume on transport init Archie Pusaka
                   ` (2 more replies)
  0 siblings, 3 replies; 4+ messages in thread
From: Archie Pusaka @ 2020-07-23  6:22 UTC (permalink / raw)
  To: linux-bluetooth, Luiz Augusto von Dentz; +Cc: Archie Pusaka, Michael Sun

From: Archie Pusaka <apusaka@chromium.org>

The valid range of volume is 0 - 127, yet it is stored in 16bit
data type. This patch modifies it so we use 8bit data type to
store volume instead. Furthermore we also use signed type, so
negative values can be used to indicate invalid volume.

Reviewed-by: Michael Sun <michaelfsun@google.com>
---

Changes in v4:
-Use int8_t instead of uint8_t

Changes in v3: None
Changes in v2: None

 profiles/audio/avrcp.c     | 13 ++++++-----
 profiles/audio/avrcp.h     |  5 ++---
 profiles/audio/media.c     |  4 ++--
 profiles/audio/transport.c | 45 +++++++++++++++++++-------------------
 profiles/audio/transport.h |  8 +++----
 5 files changed, 38 insertions(+), 37 deletions(-)

diff --git a/profiles/audio/avrcp.c b/profiles/audio/avrcp.c
index 1bf85041e..d2d1d9dae 100644
--- a/profiles/audio/avrcp.c
+++ b/profiles/audio/avrcp.c
@@ -1660,7 +1660,7 @@ static uint8_t avrcp_handle_register_notification(struct avrcp *session,
 		break;
 	case AVRCP_EVENT_VOLUME_CHANGED:
 		pdu->params[1] = media_transport_get_device_volume(dev);
-		if (pdu->params[1] > 127)
+		if (pdu->params[1] < 0)
 			goto err;
 
 		len = 2;
@@ -1757,7 +1757,7 @@ static uint8_t avrcp_handle_set_absolute_volume(struct avrcp *session,
 						uint8_t transaction)
 {
 	uint16_t len = ntohs(pdu->params_len);
-	uint8_t volume;
+	int8_t volume;
 
 	if (len != 1)
 		goto err;
@@ -3623,7 +3623,7 @@ static void avrcp_volume_changed(struct avrcp *session,
 						struct avrcp_header *pdu)
 {
 	struct avrcp_player *player = target_get_player(session);
-	uint8_t volume;
+	int8_t volume;
 
 	volume = pdu->params[1] & 0x7F;
 
@@ -4371,7 +4371,7 @@ static gboolean avrcp_handle_set_volume(struct avctp *conn, uint8_t code,
 	struct avrcp *session = user_data;
 	struct avrcp_player *player = target_get_player(session);
 	struct avrcp_header *pdu = (void *) operands;
-	uint8_t volume;
+	int8_t volume;
 
 	if (code == AVC_CTYPE_REJECTED || code == AVC_CTYPE_NOT_IMPLEMENTED ||
 								pdu == NULL)
@@ -4434,13 +4434,16 @@ static int avrcp_event(struct avrcp *session, uint8_t id, const void *data)
 	return err;
 }
 
-int avrcp_set_volume(struct btd_device *dev, uint8_t volume, bool notify)
+int avrcp_set_volume(struct btd_device *dev, int8_t volume, bool notify)
 {
 	struct avrcp_server *server;
 	struct avrcp *session;
 	uint8_t buf[AVRCP_HEADER_LENGTH + 1];
 	struct avrcp_header *pdu = (void *) buf;
 
+	if (volume < 0)
+		return -EINVAL;
+
 	server = find_server(servers, device_get_adapter(dev));
 	if (server == NULL)
 		return -EINVAL;
diff --git a/profiles/audio/avrcp.h b/profiles/audio/avrcp.h
index 86d310c73..026a820f5 100644
--- a/profiles/audio/avrcp.h
+++ b/profiles/audio/avrcp.h
@@ -94,7 +94,7 @@ struct avrcp_player_cb {
 	uint32_t (*get_position) (void *user_data);
 	uint32_t (*get_duration) (void *user_data);
 	const char *(*get_name) (void *user_data);
-	void (*set_volume) (uint8_t volume, struct btd_device *dev,
+	void (*set_volume) (int8_t volume, struct btd_device *dev,
 							void *user_data);
 	bool (*play) (void *user_data);
 	bool (*stop) (void *user_data);
@@ -103,7 +103,7 @@ struct avrcp_player_cb {
 	bool (*previous) (void *user_data);
 };
 
-int avrcp_set_volume(struct btd_device *dev, uint8_t volume, bool notify);
+int avrcp_set_volume(struct btd_device *dev, int8_t volume, bool notify);
 
 struct avrcp_player *avrcp_register_player(struct btd_adapter *adapter,
 						struct avrcp_player_cb *cb,
@@ -114,6 +114,5 @@ void avrcp_unregister_player(struct avrcp_player *player);
 void avrcp_player_event(struct avrcp_player *player, uint8_t id,
 							const void *data);
 
-
 size_t avrcp_handle_vendor_reject(uint8_t *code, uint8_t *operands);
 size_t avrcp_browsing_general_reject(uint8_t *operands);
diff --git a/profiles/audio/media.c b/profiles/audio/media.c
index a0173fdd4..d4d58ec86 100644
--- a/profiles/audio/media.c
+++ b/profiles/audio/media.c
@@ -120,7 +120,7 @@ struct media_player {
 	char			*status;
 	uint32_t		position;
 	uint32_t		duration;
-	uint8_t			volume;
+	int8_t			volume;
 	GTimer			*timer;
 	bool			play;
 	bool			pause;
@@ -1199,7 +1199,7 @@ static uint32_t get_duration(void *user_data)
 	return mp->duration;
 }
 
-static void set_volume(uint8_t volume, struct btd_device *dev, void *user_data)
+static void set_volume(int8_t volume, struct btd_device *dev, void *user_data)
 {
 	struct media_player *mp = user_data;
 
diff --git a/profiles/audio/transport.c b/profiles/audio/transport.c
index 48fabba9b..2ae5118c4 100644
--- a/profiles/audio/transport.c
+++ b/profiles/audio/transport.c
@@ -86,7 +86,7 @@ struct media_owner {
 struct a2dp_transport {
 	struct avdtp		*session;
 	uint16_t		delay;
-	uint16_t		volume;
+	int8_t			volume;
 };
 
 struct media_transport {
@@ -634,7 +634,7 @@ static gboolean volume_exists(const GDBusPropertyTable *property, void *data)
 	struct media_transport *transport = data;
 	struct a2dp_transport *a2dp = transport->data;
 
-	return a2dp->volume <= 127;
+	return a2dp->volume >= 0;
 }
 
 static gboolean get_volume(const GDBusPropertyTable *property,
@@ -642,8 +642,9 @@ static gboolean get_volume(const GDBusPropertyTable *property,
 {
 	struct media_transport *transport = data;
 	struct a2dp_transport *a2dp = transport->data;
+	uint16_t volume = (uint16_t)a2dp->volume;
 
-	dbus_message_iter_append_basic(iter, DBUS_TYPE_UINT16, &a2dp->volume);
+	dbus_message_iter_append_basic(iter, DBUS_TYPE_UINT16, &volume);
 
 	return TRUE;
 }
@@ -654,27 +655,20 @@ static void set_volume(const GDBusPropertyTable *property,
 {
 	struct media_transport *transport = data;
 	struct a2dp_transport *a2dp = transport->data;
-	uint16_t volume;
+	uint16_t arg;
+	int8_t volume;
 	bool notify;
 
-	if (dbus_message_iter_get_arg_type(iter) != DBUS_TYPE_UINT16) {
-		g_dbus_pending_property_error(id,
-					ERROR_INTERFACE ".InvalidArguments",
-					"Invalid arguments in method call");
-		return;
-	}
+	if (dbus_message_iter_get_arg_type(iter) != DBUS_TYPE_UINT16)
+		goto error;
 
-	dbus_message_iter_get_basic(iter, &volume);
-
-	if (volume > 127) {
-		g_dbus_pending_property_error(id,
-					ERROR_INTERFACE ".InvalidArguments",
-					"Invalid arguments in method call");
-		return;
-	}
+	dbus_message_iter_get_basic(iter, &arg);
+	if (arg > INT8_MAX)
+		goto error;
 
 	g_dbus_pending_property_success(id);
 
+	volume = (int8_t)arg;
 	if (a2dp->volume == volume)
 		return;
 
@@ -688,6 +682,11 @@ static void set_volume(const GDBusPropertyTable *property,
 						"Volume");
 
 	avrcp_set_volume(transport->device, volume, notify);
+	return;
+
+error:
+	g_dbus_pending_property_error(id, ERROR_INTERFACE ".InvalidArguments",
+					"Invalid arguments in method call");
 }
 
 static gboolean endpoint_exists(const GDBusPropertyTable *property, void *data)
@@ -931,14 +930,14 @@ struct btd_device *media_transport_get_dev(struct media_transport *transport)
 	return transport->device;
 }
 
-uint16_t media_transport_get_volume(struct media_transport *transport)
+int8_t media_transport_get_volume(struct media_transport *transport)
 {
 	struct a2dp_transport *a2dp = transport->data;
 	return a2dp->volume;
 }
 
 void media_transport_update_volume(struct media_transport *transport,
-								uint8_t volume)
+								int8_t volume)
 {
 	struct a2dp_transport *a2dp = transport->data;
 
@@ -953,12 +952,12 @@ void media_transport_update_volume(struct media_transport *transport,
 					MEDIA_TRANSPORT_INTERFACE, "Volume");
 }
 
-uint8_t media_transport_get_device_volume(struct btd_device *dev)
+int8_t media_transport_get_device_volume(struct btd_device *dev)
 {
 	GSList *l;
 
 	if (dev == NULL)
-		return 128;
+		return -1;
 
 	for (l = transports; l; l = l->next) {
 		struct media_transport *transport = l->data;
@@ -974,7 +973,7 @@ uint8_t media_transport_get_device_volume(struct btd_device *dev)
 }
 
 void media_transport_update_device_volume(struct btd_device *dev,
-								uint8_t volume)
+								int8_t volume)
 {
 	GSList *l;
 
diff --git a/profiles/audio/transport.h b/profiles/audio/transport.h
index ac542bf6c..78024372f 100644
--- a/profiles/audio/transport.h
+++ b/profiles/audio/transport.h
@@ -32,14 +32,14 @@ struct media_transport *media_transport_create(struct btd_device *device,
 void media_transport_destroy(struct media_transport *transport);
 const char *media_transport_get_path(struct media_transport *transport);
 struct btd_device *media_transport_get_dev(struct media_transport *transport);
-uint16_t media_transport_get_volume(struct media_transport *transport);
+int8_t media_transport_get_volume(struct media_transport *transport);
 void media_transport_update_delay(struct media_transport *transport,
 							uint16_t delay);
 void media_transport_update_volume(struct media_transport *transport,
-								uint8_t volume);
+								int8_t volume);
 void transport_get_properties(struct media_transport *transport,
 							DBusMessageIter *iter);
 
-uint8_t media_transport_get_device_volume(struct btd_device *dev);
+int8_t media_transport_get_device_volume(struct btd_device *dev);
 void media_transport_update_device_volume(struct btd_device *dev,
-								uint8_t volume);
+								int8_t volume);
-- 
2.28.0.rc0.105.gf9edc3c819-goog


^ permalink raw reply related	[flat|nested] 4+ messages in thread

* [Bluez PATCH v4 2/2] audio/transport: supply volume on transport init
  2020-07-23  6:22 [Bluez PATCH v4 1/2] audio/transport: change volume to 8bit Archie Pusaka
@ 2020-07-23  6:22 ` Archie Pusaka
  2020-07-23  6:49 ` [Bluez,v4,1/2] audio/transport: change volume to 8bit bluez.test.bot
  2020-07-23  6:51 ` bluez.test.bot
  2 siblings, 0 replies; 4+ messages in thread
From: Archie Pusaka @ 2020-07-23  6:22 UTC (permalink / raw)
  To: linux-bluetooth, Luiz Augusto von Dentz; +Cc: Archie Pusaka, Yu Liu

From: Archie Pusaka <apusaka@chromium.org>

Sometimes the response of RegisterNotification for volume change
event came before we create the transport for the corresponding
device. If that happens, the volume will be stuck to an
uninitialized invalid value. The property Volume of
MediaTransport1 will also be left unaccessible.

This patch supplies the initial volume when creating a new
transport. The value is obtained from the media_player object.
However, since the avrcp session might not be created by the time
the transport is created, we also try to initialize the volume
when creating avrcp session.

Reviewed-by: Yu Liu <yudiliu@google.com>
---

Changes in v4: None
Changes in v3:
-Add missing library

Changes in v2:
-Get the volume from media_player instead of from separate list

 profiles/audio/avrcp.c     | 27 ++++++++++++++++-
 profiles/audio/avrcp.h     |  2 ++
 profiles/audio/media.c     | 60 +++++++++++++++++++++++++++++---------
 profiles/audio/media.h     |  2 ++
 profiles/audio/transport.c |  2 +-
 5 files changed, 77 insertions(+), 16 deletions(-)

diff --git a/profiles/audio/avrcp.c b/profiles/audio/avrcp.c
index d2d1d9dae..0ea66c671 100644
--- a/profiles/audio/avrcp.c
+++ b/profiles/audio/avrcp.c
@@ -64,6 +64,7 @@
 #include "avctp.h"
 #include "avrcp.h"
 #include "control.h"
+#include "media.h"
 #include "player.h"
 #include "transport.h"
 
@@ -1701,7 +1702,6 @@ static uint8_t avrcp_handle_request_continuing(struct avrcp *session,
 	if (pending->pdu_id != pdu->params[0])
 		goto err;
 
-
 	len = 0;
 	pending->attr_ids = player_fill_media_attribute(player,
 							pending->attr_ids,
@@ -4037,8 +4037,12 @@ static void target_init(struct avrcp *session)
 
 	player = g_slist_nth_data(server->players, 0);
 	if (player != NULL) {
+		int8_t init_volume;
 		target->player = player;
 		player->sessions = g_slist_prepend(player->sessions, session);
+
+		init_volume = media_player_get_device_volume(session->dev);
+		media_transport_update_device_volume(session->dev, init_volume);
 	}
 
 	session->supported_events |= (1 << AVRCP_EVENT_STATUS_CHANGED) |
@@ -4476,6 +4480,27 @@ int avrcp_set_volume(struct btd_device *dev, int8_t volume, bool notify)
 					avrcp_handle_set_volume, session);
 }
 
+struct avrcp_player *avrcp_get_target_player_by_device(struct btd_device *dev)
+{
+	struct avrcp_server *server;
+	struct avrcp *session;
+	struct avrcp_data *target;
+
+	server = find_server(servers, device_get_adapter(dev));
+	if (server == NULL)
+		return NULL;
+
+	session = find_session(server->sessions, dev);
+	if (session == NULL)
+		return NULL;
+
+	target = session->target;
+	if (target == NULL)
+		return NULL;
+
+	return target->player;
+}
+
 static int avrcp_connect(struct btd_service *service)
 {
 	struct btd_device *dev = btd_service_get_device(service);
diff --git a/profiles/audio/avrcp.h b/profiles/audio/avrcp.h
index 026a820f5..702d57442 100644
--- a/profiles/audio/avrcp.h
+++ b/profiles/audio/avrcp.h
@@ -116,3 +116,5 @@ void avrcp_player_event(struct avrcp_player *player, uint8_t id,
 
 size_t avrcp_handle_vendor_reject(uint8_t *code, uint8_t *operands);
 size_t avrcp_browsing_general_reject(uint8_t *operands);
+
+struct avrcp_player *avrcp_get_target_player_by_device(struct btd_device *dev);
diff --git a/profiles/audio/media.c b/profiles/audio/media.c
index d4d58ec86..02bf82a49 100644
--- a/profiles/audio/media.c
+++ b/profiles/audio/media.c
@@ -239,6 +239,20 @@ static void media_endpoint_exit(DBusConnection *connection, void *user_data)
 	media_endpoint_remove(endpoint);
 }
 
+static struct media_adapter *find_adapter(struct btd_device *device)
+{
+	GSList *l;
+
+	for (l = adapters; l; l = l->next) {
+		struct media_adapter *adapter = l->data;
+
+		if (adapter->btd_adapter == device_get_adapter(device))
+			return adapter;
+	}
+
+	return NULL;
+}
+
 static void clear_configuration(struct media_endpoint *endpoint,
 					struct media_transport *transport)
 {
@@ -426,6 +440,33 @@ struct a2dp_config_data {
 	a2dp_endpoint_config_t cb;
 };
 
+int8_t media_player_get_device_volume(struct btd_device *device)
+{
+	struct avrcp_player *target_player;
+	struct media_adapter *adapter;
+	GSList *l;
+
+	if (!device)
+		return -1;
+
+	target_player = avrcp_get_target_player_by_device(device);
+	if (!target_player)
+		return -1;
+
+	adapter = find_adapter(device);
+	if (!adapter)
+		return -1;
+
+	for (l = adapter->players; l; l = l->next) {
+		struct media_player *mp = l->data;
+
+		if (mp->player == target_player)
+			return mp->volume;
+	}
+
+	return -1;
+}
+
 static gboolean set_configuration(struct media_endpoint *endpoint,
 					uint8_t *configuration, size_t size,
 					media_endpoint_cb_t cb,
@@ -439,6 +480,7 @@ static gboolean set_configuration(struct media_endpoint *endpoint,
 	const char *path;
 	DBusMessageIter iter;
 	struct media_transport *transport;
+	int8_t init_volume;
 
 	transport = find_device_transport(endpoint, device);
 
@@ -451,6 +493,9 @@ static gboolean set_configuration(struct media_endpoint *endpoint,
 	if (transport == NULL)
 		return FALSE;
 
+	init_volume = media_player_get_device_volume(device);
+	media_transport_update_volume(transport, init_volume);
+
 	msg = dbus_message_new_method_call(endpoint->sender, endpoint->path,
 						MEDIA_ENDPOINT_INTERFACE,
 						"SetConfiguration");
@@ -646,20 +691,6 @@ static gboolean endpoint_init_a2dp_sink(struct media_endpoint *endpoint,
 	return TRUE;
 }
 
-static struct media_adapter *find_adapter(struct btd_device *device)
-{
-	GSList *l;
-
-	for (l = adapters; l; l = l->next) {
-		struct media_adapter *adapter = l->data;
-
-		if (adapter->btd_adapter == device_get_adapter(device))
-			return adapter;
-	}
-
-	return NULL;
-}
-
 static bool endpoint_properties_exists(const char *uuid,
 						struct btd_device *dev,
 						void *user_data)
@@ -1779,6 +1810,7 @@ static struct media_player *media_player_create(struct media_adapter *adapter,
 	mp->sender = g_strdup(sender);
 	mp->path = g_strdup(path);
 	mp->timer = g_timer_new();
+	mp->volume = -1;
 
 	mp->watch = g_dbus_add_disconnect_watch(conn, sender,
 						media_player_exit, mp,
diff --git a/profiles/audio/media.h b/profiles/audio/media.h
index dd630d432..53694f4c6 100644
--- a/profiles/audio/media.h
+++ b/profiles/audio/media.h
@@ -33,3 +33,5 @@ void media_unregister(struct btd_adapter *btd_adapter);
 struct a2dp_sep *media_endpoint_get_sep(struct media_endpoint *endpoint);
 const char *media_endpoint_get_uuid(struct media_endpoint *endpoint);
 uint8_t media_endpoint_get_codec(struct media_endpoint *endpoint);
+
+int8_t media_player_get_device_volume(struct btd_device *device);
diff --git a/profiles/audio/transport.c b/profiles/audio/transport.c
index 2ae5118c4..a2c4f7dfb 100644
--- a/profiles/audio/transport.c
+++ b/profiles/audio/transport.c
@@ -977,7 +977,7 @@ void media_transport_update_device_volume(struct btd_device *dev,
 {
 	GSList *l;
 
-	if (dev == NULL)
+	if (dev == NULL || volume < 0)
 		return;
 
 	for (l = transports; l; l = l->next) {
-- 
2.28.0.rc0.105.gf9edc3c819-goog


^ permalink raw reply related	[flat|nested] 4+ messages in thread

* RE: [Bluez,v4,1/2] audio/transport: change volume to 8bit
  2020-07-23  6:22 [Bluez PATCH v4 1/2] audio/transport: change volume to 8bit Archie Pusaka
  2020-07-23  6:22 ` [Bluez PATCH v4 2/2] audio/transport: supply volume on transport init Archie Pusaka
@ 2020-07-23  6:49 ` bluez.test.bot
  2020-07-23  6:51 ` bluez.test.bot
  2 siblings, 0 replies; 4+ messages in thread
From: bluez.test.bot @ 2020-07-23  6:49 UTC (permalink / raw)
  To: linux-bluetooth, apusaka

[-- Attachment #1: Type: text/plain, Size: 1003 bytes --]


This is automated email and please do not reply to this email!

Dear submitter,

Thank you for submitting the patches to the linux bluetooth mailing list.
While we are preparing for reviewing the patches, we found the following
issue/warning.

Test Result:
checkpatch Failed

Outputs:
WARNING:SPACING: Unnecessary space before function pointer arguments
#80: FILE: profiles/audio/avrcp.h:97:
+	void (*set_volume) (int8_t volume, struct btd_device *dev,

- total: 0 errors, 1 warnings, 215 lines checked

NOTE: For some of the reported defects, checkpatch may be able to
      mechanically convert to the typical style using --fix or --fix-inplace.

Your patch has style problems, please review.

NOTE: Ignored message types: COMMIT_MESSAGE COMPLEX_MACRO CONST_STRUCT FILE_PATH_CHANGES MISSING_SIGN_OFF PREFER_PACKED SPLIT_STRING SSCANF_TO_KSTRTO

NOTE: If any of the errors are false positives, please report
      them to the maintainer, see CHECKPATCH in MAINTAINERS.



---
Regards,
Linux Bluetooth

^ permalink raw reply	[flat|nested] 4+ messages in thread

* RE: [Bluez,v4,1/2] audio/transport: change volume to 8bit
  2020-07-23  6:22 [Bluez PATCH v4 1/2] audio/transport: change volume to 8bit Archie Pusaka
  2020-07-23  6:22 ` [Bluez PATCH v4 2/2] audio/transport: supply volume on transport init Archie Pusaka
  2020-07-23  6:49 ` [Bluez,v4,1/2] audio/transport: change volume to 8bit bluez.test.bot
@ 2020-07-23  6:51 ` bluez.test.bot
  2 siblings, 0 replies; 4+ messages in thread
From: bluez.test.bot @ 2020-07-23  6:51 UTC (permalink / raw)
  To: linux-bluetooth, apusaka

[-- Attachment #1: Type: text/plain, Size: 1036 bytes --]


This is automated email and please do not reply to this email!

Dear submitter,

Thank you for submitting the patches to the linux bluetooth mailing list.
While we are preparing for reviewing the patches, we found the following
issue/warning.

Test Result:
checkbuild Failed

Outputs:
ar: `u' modifier ignored since `D' is the default (see `U')
ar: `u' modifier ignored since `D' is the default (see `U')
ar: `u' modifier ignored since `D' is the default (see `U')
ar: `u' modifier ignored since `D' is the default (see `U')
ar: `u' modifier ignored since `D' is the default (see `U')
profiles/audio/avrcp.c: In function ‘avrcp_handle_register_notification’:
profiles/audio/avrcp.c:1664:22: error: comparison is always false due to limited range of data type [-Werror=type-limits]
 1664 |   if (pdu->params[1] < 0)
      |                      ^
cc1: all warnings being treated as errors
make[1]: *** [Makefile:8467: profiles/audio/bluetoothd-avrcp.o] Error 1
make: *** [Makefile:4010: all] Error 2



---
Regards,
Linux Bluetooth

^ permalink raw reply	[flat|nested] 4+ messages in thread

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2020-07-23  6:22 [Bluez PATCH v4 1/2] audio/transport: change volume to 8bit Archie Pusaka
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