Hi Nick, On Wed, Jun 23, 2021 at 3:12 AM Nick Shaforostoff <shaforostoff@xxxxxxxxx> wrote: > > Hi! I am implementing audio sink on my desktop linux (as a first step; > second step is linux embedded). My application uses Qt 5.15, and also > bluez-qt library from KDE project. I am using bluez 5.55 > > On my laptop I have organized registering of endpoint to accept sbc > audio from my android smartphone. When I receive > BluezQt::MediaTransport::stateChanged signal with state = > BluezQt::MediaTransport::State::Pending, I call transport->acquire(). > > In reply I get file descriptor 33, mtu read 672, mtu write 1008. > > But then, when I start new thread that reads from this file > descriptor, I get errno 9 (returned length being -1) all the time (on > each for(;;) loop iteration). > > On smartphones's side everything looks good - it streams audio over > bluetooth (in youtube application) and I can change bluetooth volume. > > I found out that bluetooth documentation is scarce. The only detailed > document I found besides *-api.txt files is > https://www.lightofdawn.org/blog/?viewDetailed=00032 but it talks > about bluez 4 > > Could you please give me advice on where to look to fix this problem? > > This is the log from bluetoothd -d: > > Jun 23 10:52:52 debian-e330 bluetoothd[629]: Endpoint registered: > sender=:1.170 path=/MediaEndpoint/Sink/Sbc > > Jun 23 10:52:52 debian-e330 bluetoothd[629]: > src/adapter.c:dev_class_changed_callback() Class: 0x14010c > > > Jun 23 10:52:53 debian-e330 bluetoothd[629]: > src/adapter.c:device_found_callback() hci0 addr 60:AB:67:17:74:03, > rssi -79 flags 0x0000 eir_len 170 > Jun 23 10:52:53 debian-e330 bluetoothd[629]: > src/device.c:device_set_legacy() legacy 0 > Jun 23 10:52:53 debian-e330 bluetoothd[629]: > src/device.c:device_set_rssi_with_delta() rssi -79 > > > > > Jun 23 10:52:57 debian-e330 bluetoothd[629]: > src/adapter.c:discovering_callback() hci0 type 7 discovering 0 method > 1 > Jun 23 10:52:57 debian-e330 bluetoothd[629]: > src/adapter.c:trigger_start_discovery() > Jun 23 10:52:57 debian-e330 bluetoothd[629]: > src/adapter.c:cancel_passive_scanning() > Jun 23 10:52:57 debian-e330 bluetoothd[629]: > src/adapter.c:start_discovery_timeout() > Jun 23 10:52:57 debian-e330 bluetoothd[629]: > src/adapter.c:start_discovery_timeout() > adapter->current_discovery_filter == 1 > Jun 23 10:52:57 debian-e330 bluetoothd[629]: > src/adapter.c:start_discovery_timeout() sending > MGMT_OP_START_SERVICE_DISCOVERY 127, 7, 0 > Jun 23 10:52:57 debian-e330 bluetoothd[629]: > src/adapter.c:start_discovery_complete() status 0x00 > Jun 23 10:52:57 debian-e330 bluetoothd[629]: > src/adapter.c:discovering_callback() hci0 type 7 discovering 1 method > 1 > Jun 23 10:53:02 debian-e330 bluetoothd[629]: > src/adapter.c:connected_callback() hci0 device 60:AB:67:17:74:03 > connected eir_len 12 > Jun 23 10:53:03 debian-e330 bluetoothd[629]: > profiles/audio/a2dp.c:confirm_cb() AVDTP: incoming connect from > 60:AB:67:17:74:03 > Jun 23 10:53:03 debian-e330 bluetoothd[629]: > profiles/audio/source.c:source_set_state() State changed > /org/bluez/hci0/dev_60_AB_67_17_74_03: SOURCE_STATE_DISCONNECTED -> > SOURCE_STATE_CONNECTING > Jun 23 10:53:03 debian-e330 bluetoothd[629]: > profiles/audio/avdtp.c:avdtp_connect_cb() AVDTP: connected signaling > channel to 60:AB:67:17:74:03 > Jun 23 10:53:03 debian-e330 bluetoothd[629]: > profiles/audio/avdtp.c:avdtp_connect_cb() AVDTP imtu=672, omtu=672 > Jun 23 10:53:03 debian-e330 bluetoothd[629]: > profiles/audio/avdtp.c:avdtp_register_remote_sep() seid 1 type 0 media > 0 delay_reporting true > Jun 23 10:53:03 debian-e330 bluetoothd[629]: > profiles/audio/a2dp.c:register_remote_sep() Found remote SEP: > /org/bluez/hci0/dev_60_AB_67_17_74_03/sep1 > Jun 23 10:53:03 debian-e330 bluetoothd[629]: > profiles/audio/avdtp.c:avdtp_ref() 0x560dcaedf8a0: ref=1 > Jun 23 10:53:03 debian-e330 bluetoothd[629]: > profiles/audio/avdtp.c:set_disconnect_timer() timeout 1 > Jun 23 10:53:03 debian-e330 bluetoothd[629]: profiles/audio/avdtp.c:session_cb() > Jun 23 10:53:03 debian-e330 bluetoothd[629]: > profiles/audio/avdtp.c:avdtp_parse_cmd() Received DISCOVER_CMD > Jun 23 10:53:03 debian-e330 bluetoothd[629]: profiles/audio/avdtp.c:session_cb() > Jun 23 10:53:03 debian-e330 bluetoothd[629]: > profiles/audio/avdtp.c:avdtp_parse_cmd() Received > GET_ALL_CAPABILITIES_CMD > Jun 23 10:53:03 debian-e330 bluetoothd[629]: > profiles/audio/a2dp.c:endpoint_getcap_ind() Sink 0x560dcaeb1050: > Get_Capability_Ind > Jun 23 10:53:03 debian-e330 bluetoothd[629]: profiles/audio/avdtp.c:session_cb() > Jun 23 10:53:03 debian-e330 bluetoothd[629]: > profiles/audio/avdtp.c:avdtp_parse_cmd() Received > SET_CONFIGURATION_CMD > Jun 23 10:53:03 debian-e330 bluetoothd[629]: > profiles/audio/avdtp.c:caps_to_list() Invalid capability data in > getcap resp > Jun 23 10:53:03 debian-e330 bluetoothd[629]: > profiles/audio/a2dp.c:endpoint_setconf_ind() Sink 0x560dcaeb1050: > Set_Configuration_Ind > Jun 23 10:53:03 debian-e330 bluetoothd[629]: > profiles/audio/avdtp.c:avdtp_ref() 0x560dcaedf8a0: ref=2 > Jun 23 10:53:03 debian-e330 bluetoothd[629]: > profiles/audio/avdtp.c:avdtp_unref() 0x560dcaedf8a0: ref=1 > Jun 23 10:53:03 debian-e330 bluetoothd[629]: > profiles/audio/a2dp.c:setup_ref() 0x560dcaec4cc0: ref=1 > Jun 23 10:53:03 debian-e330 bluetoothd[629]: > profiles/audio/a2dp.c:setup_ref() 0x560dcaec4cc0: ref=2 > Jun 23 10:53:03 debian-e330 bluetoothd[629]: > profiles/audio/media.c:media_endpoint_async_call() Calling > SetConfiguration: name = :1.170 path = /MediaEndpoint/Sink/Sbc > Jun 23 10:53:03 debian-e330 bluetoothd[629]: > profiles/audio/avdtp.c:avdtp_ref() 0x560dcaedf8a0: ref=2 > Jun 23 10:53:03 debian-e330 bluetoothd[629]: > profiles/audio/avdtp.c:avdtp_sep_set_state() stream state changed: > IDLE -> CONFIGURED > Jun 23 10:53:03 debian-e330 bluetoothd[629]: > profiles/audio/a2dp.c:setup_unref() 0x560dcaec4cc0: ref=1 > Jun 23 10:53:03 debian-e330 bluetoothd[629]: > profiles/audio/a2dp.c:setup_unref() 0x560dcaec4cc0: ref=0 > Jun 23 10:53:03 debian-e330 bluetoothd[629]: > profiles/audio/a2dp.c:setup_free() 0x560dcaec4cc0 > Jun 23 10:53:03 debian-e330 bluetoothd[629]: > profiles/audio/avdtp.c:avdtp_unref() 0x560dcaedf8a0: ref=1 > Jun 23 10:53:05 debian-e330 bluetoothd[629]: profiles/audio/avdtp.c:session_cb() > Jun 23 10:53:05 debian-e330 bluetoothd[629]: > profiles/audio/avdtp.c:avdtp_parse_cmd() Received OPEN_CMD > Jun 23 10:53:05 debian-e330 bluetoothd[629]: > profiles/audio/a2dp.c:open_ind() Sink 0x560dcaeb1050: Open_Ind > Jun 23 10:53:05 debian-e330 bluetoothd[629]: > profiles/audio/avdtp.c:avdtp_ref() 0x560dcaedf8a0: ref=2 > Jun 23 10:53:05 debian-e330 bluetoothd[629]: > profiles/audio/a2dp.c:setup_ref() 0x560dcaec4cc0: ref=1 > Jun 23 10:53:05 debian-e330 bluetoothd[629]: > profiles/audio/a2dp.c:confirm_cb() AVDTP: incoming connect from > 60:AB:67:17:74:03 > Jun 23 10:53:05 debian-e330 bluetoothd[629]: > profiles/audio/avdtp.c:avdtp_sep_set_state() stream state changed: > CONFIGURED -> OPEN > Jun 23 10:53:05 debian-e330 bluetoothd[629]: > src/service.c:change_state() 0x560dcaebb5a0: device 60:AB:67:17:74:03 > profile a2dp-source state changed: disconnected -> connected (0) > Jun 23 10:53:05 debian-e330 bluetoothd[629]: > plugins/policy.c:service_cb() Added a2dp-source reconnect 1 > Jun 23 10:53:05 debian-e330 bluetoothd[629]: > profiles/audio/source.c:source_set_state() State changed > /org/bluez/hci0/dev_60_AB_67_17_74_03: SOURCE_STATE_CONNECTING -> > SOURCE_STATE_CONNECTED > Jun 23 10:53:05 debian-e330 bluetoothd[629]: > profiles/audio/transport.c:transport_update_playing() > /org/bluez/hci0/dev_60_AB_67_17_74_03/fd1 State=TRANSPORT_STATE_IDLE > Playing=0 > Jun 23 10:53:05 debian-e330 bluetoothd[629]: > profiles/audio/a2dp.c:setup_unref() 0x560dcaec4cc0: ref=0 > Jun 23 10:53:05 debian-e330 bluetoothd[629]: > profiles/audio/a2dp.c:setup_free() 0x560dcaec4cc0 > Jun 23 10:53:05 debian-e330 bluetoothd[629]: > profiles/audio/avdtp.c:avdtp_unref() 0x560dcaedf8a0: ref=1 > Jun 23 10:53:07 debian-e330 bluetoothd[629]: > src/adapter.c:stop_discovery() sender :1.170 > Jun 23 10:53:07 debian-e330 bluetoothd[629]: > src/adapter.c:discovering_callback() hci0 type 7 discovering 0 method > 1 > Jun 23 10:53:07 debian-e330 bluetoothd[629]: > src/adapter.c:trigger_start_discovery() > Jun 23 10:53:07 debian-e330 bluetoothd[629]: > src/adapter.c:cancel_passive_scanning() > Jun 23 10:53:07 debian-e330 bluetoothd[629]: > src/adapter.c:stop_discovery_complete() status 0x00 > Jun 23 10:53:07 debian-e330 bluetoothd[629]: > src/adapter.c:discovery_remove() owner :1.170 > Jun 23 10:53:07 debian-e330 bluetoothd[629]: > src/device.c:device_set_rssi_with_delta() rssi 0 > Jun 23 10:53:07 debian-e330 bluetoothd[629]: > src/adapter.c:trigger_passive_scanning() > > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > plugins/policy.c:policy_connect() > /org/bluez/hci0/dev_60_AB_67_17_74_03 profile audio-avrcp-target > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > profiles/audio/avrcp.c:avrcp_connect() path > /org/bluez/hci0/dev_60_AB_67_17_74_03 > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > profiles/audio/avctp.c:avctp_set_state() AVCTP Connecting > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > src/service.c:change_state() 0x560dcaeba730: device 60:AB:67:17:74:03 > profile audio-avrcp-target state changed: disconnected -> connecting > (0) > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > profiles/audio/avctp.c:avctp_connect_cb() AVCTP: connected to > 60:AB:67:17:74:03 > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > profiles/audio/avctp.c:init_uinput() AVRCP: uinput initialized for Mi > A3 > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > profiles/audio/avrcp.c:controller_init() 0x560dcaeae780 version 0x0103 > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > src/service.c:change_state() 0x560dcaeba730: device 60:AB:67:17:74:03 > profile audio-avrcp-target state changed: connecting -> connected (0) > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > src/device.c:device_profile_connected() audio-avrcp-target Success (0) > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > profiles/audio/player.c:media_player_controller_create() > /org/bluez/hci0/dev_60_AB_67_17_74_03/player0 > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > profiles/audio/avrcp.c:target_init() 0x560dcaee0d00 version 0x0103 > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > src/service.c:change_state() 0x560dcaea88d0: device 60:AB:67:17:74:03 > profile avrcp-controller state changed: disconnected -> connected (0) > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > profiles/audio/avctp.c:avctp_set_state() AVCTP Connected > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > profiles/audio/avrcp.c:handle_vendordep_pdu() AVRCP PDU 0x31, company > 0x001958 len 0x0005 > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > profiles/audio/avrcp.c:handle_vendordep_pdu() AVRCP PDU parameters > length don't match > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > profiles/audio/player.c:media_player_set_setting() Repeat: off > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > profiles/audio/player.c:media_player_set_setting() Shuffle: off > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > profiles/audio/player.c:media_player_set_position() 0 > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > profiles/audio/player.c:media_player_set_status() stopped > > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > profiles/audio/player.c:media_player_set_playlist_item() 0 > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > profiles/audio/player.c:media_player_set_metadata() Title: > CIAO, 2020! Полная версия > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > profiles/audio/player.c:media_player_set_metadata() Artist: Вечерний > Ургант > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > profiles/audio/player.c:media_player_set_metadata() Album: Вечерний > Ургант > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > profiles/audio/player.c:media_player_set_metadata() TrackNumber: 0 > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > profiles/audio/player.c:media_player_set_metadata() NumberOfTracks: 0 > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > profiles/audio/player.c:media_player_set_metadata() Genre: > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > profiles/audio/player.c:media_player_set_metadata() Duration: 3184000 > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > profiles/audio/player.c:media_player_set_duration() 3184000 > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > profiles/audio/player.c:media_player_set_position() 0 > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > profiles/audio/player.c:media_player_set_status() stopped > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > profiles/audio/player.c:media_player_set_duration() 3184000 > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > profiles/audio/player.c:media_player_set_position() 0 > Jun 23 10:53:08 debian-e330 bluetoothd[629]: > profiles/audio/player.c:media_player_set_status() stopped > > Jun 23 10:53:09 debian-e330 bluetoothd[629]: profiles/audio/avdtp.c:session_cb() > Jun 23 10:53:09 debian-e330 bluetoothd[629]: > profiles/audio/avdtp.c:avdtp_parse_cmd() Received START_CMD > Jun 23 10:53:09 debian-e330 bluetoothd[629]: > profiles/audio/a2dp.c:start_ind() Sink 0x560dcaeb1050: Start_Ind > Jun 23 10:53:09 debian-e330 bluetoothd[629]: > profiles/audio/avdtp.c:avdtp_ref() 0x560dcaedf8a0: ref=2 > Jun 23 10:53:09 debian-e330 bluetoothd[629]: > profiles/audio/avdtp.c:avdtp_sep_set_state() stream state changed: > OPEN -> STREAMING > Jun 23 10:53:09 debian-e330 bluetoothd[629]: > profiles/audio/source.c:source_set_state() State changed > /org/bluez/hci0/dev_60_AB_67_17_74_03: SOURCE_STATE_CONNECTED -> > SOURCE_STATE_PLAYING > Jun 23 10:53:09 debian-e330 bluetoothd[629]: > profiles/audio/transport.c:transport_update_playing() > /org/bluez/hci0/dev_60_AB_67_17_74_03/fd1 State=TRANSPORT_STATE_IDLE > Playing=1 > Jun 23 10:53:09 debian-e330 bluetoothd[629]: > profiles/audio/transport.c:transport_set_state() State changed > /org/bluez/hci0/dev_60_AB_67_17_74_03/fd1: TRANSPORT_STATE_IDLE -> > TRANSPORT_STATE_PENDING > Jun 23 10:53:09 debian-e330 bluetoothd[629]: > profiles/audio/transport.c:media_owner_create() Owner created: > sender=:1.170 > Jun 23 10:53:09 debian-e330 bluetoothd[629]: > profiles/audio/avdtp.c:avdtp_ref() 0x560dcaedf8a0: ref=3 > Jun 23 10:53:09 debian-e330 bluetoothd[629]: > profiles/audio/a2dp.c:a2dp_sep_lock() SEP 0x560dcaeb1050 locked > Jun 23 10:53:09 debian-e330 bluetoothd[629]: > profiles/audio/avdtp.c:avdtp_ref() 0x560dcaedf8a0: ref=4 > Jun 23 10:53:09 debian-e330 bluetoothd[629]: > profiles/audio/a2dp.c:setup_ref() 0x560dcaed05b0: ref=1 > Jun 23 10:53:09 debian-e330 bluetoothd[629]: > profiles/audio/avdtp.c:avdtp_unref() 0x560dcaedf8a0: ref=3 > Jun 23 10:53:09 debian-e330 bluetoothd[629]: > profiles/audio/transport.c:media_request_create() Request created: > method=Acquire id=3 > Jun 23 10:53:09 debian-e330 bluetoothd[629]: > profiles/audio/transport.c:media_owner_add() Owner :1.170 Request > Acquire > Jun 23 10:53:09 debian-e330 bluetoothd[629]: > profiles/audio/transport.c:media_transport_set_owner() Transport > /org/bluez/hci0/dev_60_AB_67_17_74_03/fd1 Owner :1.170 > Jun 23 10:53:09 debian-e330 bluetoothd[629]: > /org/bluez/hci0/dev_60_AB_67_17_74_03/fd1: fd(37) ready > Jun 23 10:53:09 debian-e330 bluetoothd[629]: > profiles/audio/transport.c:media_owner_remove() Owner :1.170 Request > Acquire > Jun 23 10:53:09 debian-e330 bluetoothd[629]: > profiles/audio/transport.c:transport_set_state() State changed > /org/bluez/hci0/dev_60_AB_67_17_74_03/fd1: TRANSPORT_STATE_PENDING -> > TRANSPORT_STATE_ACTIVE > Jun 23 10:53:09 debian-e330 bluetoothd[629]: > profiles/audio/a2dp.c:setup_unref() 0x560dcaed05b0: ref=0 > Jun 23 10:53:09 debian-e330 bluetoothd[629]: > profiles/audio/a2dp.c:setup_free() 0x560dcaed05b0 > Jun 23 10:53:09 debian-e330 bluetoothd[629]: > profiles/audio/avdtp.c:avdtp_unref() 0x560dcaedf8a0: ref=2 > Jun 23 10:53:09 debian-e330 bluetoothd[629]: > profiles/audio/player.c:media_player_set_status() playing > Jun 23 10:53:09 debian-e330 bluetoothd[629]: > profiles/audio/player.c:media_player_set_duration() 3184000 > Jun 23 10:53:09 debian-e330 bluetoothd[629]: > profiles/audio/player.c:media_player_set_position() 0 > Jun 23 10:53:09 debian-e330 bluetoothd[629]: > profiles/audio/player.c:media_player_set_status() playing > > > > > > > > > > > > ================= > And this is the output of my application, Mi A3 is my smartphone. > > Change "org.bluez.Device1" QMap(("RSSI", QVariant(short, -79))) > Change "org.bluez.Device1" QMap(("Connected", QVariant(bool, true))) > isInSet false isConnected true > CONNECTED > configurationSet "/org/bluez/hci0/dev_60_AB_67_17_74_03/fd1" > Change "org.bluez.Device1" QMap() > Change "org.bluez.Adapter1" QMap(("Discovering", QVariant(bool, false))) > Change "org.bluez.MediaControl1" QMap(("Connected", QVariant(bool, > true))("Player", QVariant(QDBusObjectPath, ))) > MediaTransportPrivate::onPropertiesChanged key "State" > QVariant(QString, "pending") > Transport state: BluezQt::MediaTransport::State::Pending "Mi A3" > Transport state: BluezQt::MediaTransport::State::Pending "Mi A3" > fd: 33 mtu read: 672 mtu write: 1008 > fd reply err 0 > fd reply mtu read write 672 1008 > fd reply fd 33 > MediaTransportPrivate::onPropertiesChanged key "State" > QVariant(QString, "active") > Transport state: BluezQt::MediaTransport::State::Active "Mi A3" > Transport state: BluezQt::MediaTransport::State::Active "Mi A3" > BluetoothAudioRead len errno -1 9 Are you sure there is any data to be read? You can check how pulseaudio/pipewire does it, Im curious why you decided to reimplement the audio handling instead of just using an existing implementation? > I use read() call: > uint8_t payload[2 * 512]; > ssize_t len = read(bluetooth_fd, payload, sizeof(payload)); > qDebug()<<"BluetoothAudioRead len errno"<<len<<errno; > > I also tried using recvmsg() the way it is done in pulseaudio, but > result is the same. -- Luiz Augusto von Dentz
