This implements the server role for the Audio Streaming for Hearing Aid specification[1]. Includes basic ability to probe the ASHA GATT service, as well as starting/stopping streaming. [1] https://source.android.com/docs/core/connect/bluetooth/asha --- Makefile.am | 3 +- lib/uuid.h | 3 + src/shared/asha.c | 497 ++++++++++++++++++++++++++++++++++++++++++++++ src/shared/asha.h | 75 +++++++ 4 files changed, 577 insertions(+), 1 deletion(-) create mode 100644 src/shared/asha.c create mode 100644 src/shared/asha.h diff --git a/Makefile.am b/Makefile.am index 05d02932f..3e6610017 100644 --- a/Makefile.am +++ b/Makefile.am @@ -238,7 +238,8 @@ shared_sources = src/shared/io.h src/shared/timeout.h \ src/shared/bass.h src/shared/bass.c \ src/shared/ccp.h src/shared/ccp.c \ src/shared/lc3.h src/shared/tty.h \ - src/shared/bap-defs.h + src/shared/bap-defs.h \ + src/shared/asha.h src/shared/asha.c if READLINE shared_sources += src/shared/shell.c src/shared/shell.h diff --git a/lib/uuid.h b/lib/uuid.h index 8404b287e..479986f06 100644 --- a/lib/uuid.h +++ b/lib/uuid.h @@ -163,6 +163,9 @@ extern "C" { #define BAA_SERVICE 0x1851 #define BAA_SERVICE_UUID "00001851-0000-1000-8000-00805f9b34fb" +#define ASHA_SERVICE 0xFDF0 +#define ASHA_PROFILE_UUID "0000FDF0-0000-1000-8000-00805f9b34fb" + #define PAC_CONTEXT 0x2bcd #define PAC_SUPPORTED_CONTEXT 0x2bce diff --git a/src/shared/asha.c b/src/shared/asha.c new file mode 100644 index 000000000..1ec6e28b7 --- /dev/null +++ b/src/shared/asha.c @@ -0,0 +1,497 @@ +// SPDX-License-Identifier: LGPL-2.1-or-later +/* + * + * BlueZ - Bluetooth protocol stack for Linux + * + * Copyright (C) 2024 Asymptotic Inc. + * + * Author: Arun Raghavan <arun@xxxxxxxxxxxxx> + * + * + */ + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif + +#define _GNU_SOURCE +#include <errno.h> + +#include <stdbool.h> +#include <stdint.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <sys/socket.h> + +#include "lib/bluetooth.h" +#include "lib/l2cap.h" +#include "lib/uuid.h" + +#include "src/shared/util.h" +#include "src/shared/att.h" +#include "src/log.h" + +#include "src/shared/queue.h" +#include "src/shared/gatt-db.h" +#include "src/shared/gatt-client.h" + +#include "asha.h" + +/* We use strings instead of uint128_t to maintain readability */ +#define ASHA_CHRC_READ_ONLY_PROPERTIES_UUID "6333651e-c481-4a3e-9169-7c902aad37bb" +#define ASHA_CHRC_AUDIO_CONTROL_POINT_UUID "f0d4de7e-4a88-476c-9d9f-1937b0996cc0" +#define ASHA_CHRC_AUDIO_STATUS_UUID "38663f1a-e711-4cac-b641-326b56404837" +#define ASHA_CHRC_VOLUME_UUID "00e4ca9e-ab14-41e4-8823-f9e70c7e91df" +#define ASHA_CHRC_LE_PSM_OUT_UUID "2d410339-82b6-42aa-b34e-e2e01df8cc1a" + +/* 2 byte SDU length, 1 byte sequence number, and then 20ms of G.722 */ +#define ASHA_MIN_MTU 163 +#define ASHA_CONNECTION_MTU 512 /* The default of 672 does not + * work */ + +struct bt_asha *bt_asha_new(const bdaddr_t *addr) +{ + struct bt_asha *asha; + + asha = new0(struct bt_asha, 1); + bacpy(&asha->addr, addr); + + return asha; +} + +void bt_asha_reset(struct bt_asha *asha) +{ + if (asha->status_notify_id) { + bt_gatt_client_unregister_notify(asha->client, + asha->status_notify_id); + } + + gatt_db_unref(asha->db); + asha->db = NULL; + + bt_gatt_client_unref(asha->client); + asha->client = NULL; + + asha->psm = 0; +} + +void bt_asha_state_reset(struct bt_asha *asha) +{ + close(asha->fd); + asha->fd = -1; + + asha->state = ASHA_STOPPED; + asha->resume_id = 0; + + asha->cb = NULL; + asha->cb_user_data = NULL; +} + +void bt_asha_free(struct bt_asha *asha) +{ + gatt_db_unref(asha->db); + bt_gatt_client_unref(asha->client); + free(asha); +} + +uint16_t bt_asha_get_render_delay(struct bt_asha *asha) +{ + return asha->render_delay; +} + +enum bt_asha_state_t bt_asha_get_state(struct bt_asha *asha) +{ + return asha->state; +} + +int bt_asha_get_fd(struct bt_asha *asha) +{ + return asha->fd; +} + +uint16_t bt_asha_get_omtu(struct bt_asha *asha) +{ + return asha->omtu; +} +uint16_t bt_asha_get_imtu(struct bt_asha *asha) +{ + return asha->imtu; +} + +int bt_asha_connect_socket(struct bt_asha *asha) +{ + int fd = 0, err; + struct sockaddr_l2 addr = { 0, }; + struct l2cap_options opts; + socklen_t len; + + if (asha->state != ASHA_STOPPED) { + error("ASHA device connect failed. Bad state %d", asha->state); + return 0; + } + + fd = socket(PF_BLUETOOTH, SOCK_SEQPACKET, BTPROTO_L2CAP); + if (fd < 0) { + error("Could not open L2CAP CoC socket: %s", strerror(errno)); + goto error; + } + + addr.l2_family = AF_BLUETOOTH; + addr.l2_bdaddr_type = BDADDR_LE_PUBLIC; + + /* + * We need to bind before connect to work around getting the wrong addr + * type on older(?) kernels + */ + err = bind(fd, (struct sockaddr *) &addr, sizeof(addr)); + if (err < 0) { + error("Could not bind L2CAP CoC socket: %s", strerror(errno)); + goto error; + } + + addr.l2_psm = asha->psm; + bacpy(&addr.l2_bdaddr, &asha->addr); + + opts.mode = BT_MODE_LE_FLOWCTL; + opts.omtu = opts.imtu = ASHA_MIN_MTU; + + err = setsockopt(fd, SOL_BLUETOOTH, BT_MODE, &opts.mode, + sizeof(opts.mode)); + if (err < 0) { + error("Could not set L2CAP CoC socket flow control mode: %s", + strerror(errno)); + /* Let this be non-fatal? */ + } + + opts.imtu = ASHA_CONNECTION_MTU; + err = setsockopt(fd, SOL_BLUETOOTH, BT_RCVMTU, &opts.imtu, + sizeof(opts.imtu)); + if (err < 0) { + error("Could not set L2CAP CoC socket receive MTU: %s", + strerror(errno)); + /* Let this be non-fatal? */ + } + + err = connect(fd, (struct sockaddr *)&addr, sizeof(addr)); + if (err < 0) { + error("Could not connect L2CAP CoC socket: %s", + strerror(errno)); + goto error; + } + + err = getsockopt(fd, SOL_BLUETOOTH, BT_SNDMTU, &opts.omtu, &len); + if (err < 0) { + error("Could not get L2CAP CoC socket receive MTU: %s", + strerror(errno)); + /* Let this be non-fatal? */ + } + + err = getsockopt(fd, SOL_BLUETOOTH, BT_RCVMTU, &opts.imtu, &len); + if (err < 0) { + error("Could not get L2CAP CoC socket receive MTU: %s", + strerror(errno)); + /* Let this be non-fatal? */ + } + + asha->fd = fd; + asha->imtu = opts.imtu; + asha->omtu = opts.omtu; + + DBG("L2CAP CoC socket is open"); + return 0; + +error: + if (fd) + close(fd); + return -1; +} + +static void asha_acp_sent(bool success, uint8_t err, void *user_data) +{ + struct bt_asha *asha = user_data; + + if (success) { + DBG("AudioControlPoint command successfully sent"); + } else { + error("Failed to send AudioControlPoint command: %d", err); + + if (asha->cb) + asha->cb(-1, asha->cb_user_data); + + bt_asha_state_reset(asha); + } +} + +static int asha_send_acp(struct bt_asha *asha, uint8_t *cmd, + unsigned int len, bt_asha_cb_t cb, void *user_data) +{ + if (!bt_gatt_client_write_value(asha->client, asha->acp_handle, cmd, + len, asha_acp_sent, asha, NULL)) { + error("Error writing ACP start"); + return -1; + } + + asha->cb = cb; + asha->cb_user_data = user_data; + + return 0; +} + +unsigned int bt_asha_start(struct bt_asha *asha, bt_asha_cb_t cb, + void *user_data) +{ + uint8_t acp_start_cmd[] = { + 0x01, /* START */ + 0x01, /* G.722, 16 kHz */ + 0, /* Unknown media type */ + asha->volume, /* Volume */ + 0, /* Other disconnected */ + }; + int ret; + + if (asha->state != ASHA_STOPPED) { + error("ASHA device start failed. Bad state %d", asha->state); + return 0; + } + + ret = asha_send_acp(asha, acp_start_cmd, sizeof(acp_start_cmd), cb, + user_data); + if (ret < 0) + return 0; + + asha->state = ASHA_STARTING; + + return (++asha->resume_id); +} + +unsigned int bt_asha_stop(struct bt_asha *asha, bt_asha_cb_t cb, + void *user_data) +{ + uint8_t acp_stop_cmd[] = { + 0x02, /* STOP */ + }; + int ret; + + if (asha->state != ASHA_STARTED) + return 0; + + asha->state = ASHA_STOPPING; + + ret = asha_send_acp(asha, acp_stop_cmd, sizeof(acp_stop_cmd), cb, + user_data); + if (ret < 0) + return 0; + + return asha->resume_id; +} + +int8_t bt_asha_get_volume(struct bt_asha *asha) +{ + return asha->volume; +} + +bool bt_asha_set_volume(struct bt_asha *asha, int8_t volume) +{ + if (!bt_gatt_client_write_without_response(asha->client, + asha->volume_handle, false, + (const uint8_t *)&volume, 1)) { + error("Error writing volume"); + return false; + } + + asha->volume = volume; + return true; +} + +static bool uuid_cmp(const char *uuid1, const bt_uuid_t *uuid2) +{ + bt_uuid_t lhs; + + bt_string_to_uuid(&lhs, uuid1); + + return bt_uuid_cmp(&lhs, uuid2) == 0; +} + +static void read_psm(bool success, + uint8_t att_ecode, + const uint8_t *value, + uint16_t length, + void *user_data) +{ + struct bt_asha *asha = user_data; + + if (!success) { + DBG("Reading PSM failed with ATT error: %u", att_ecode); + return; + } + + if (length != 2) { + DBG("Reading PSM failed: unexpected length %u", length); + return; + } + + asha->psm = get_le16(value); + + DBG("Got PSM: %u", asha->psm); +} + +static void read_rops(bool success, + uint8_t att_ecode, + const uint8_t *value, + uint16_t length, + void *user_data) +{ + struct bt_asha *asha = user_data; + + if (!success) { + DBG("Reading ROPs failed with ATT error: %u", att_ecode); + return; + } + + if (length != 17) { + DBG("Reading ROPs failed: unexpected length %u", length); + return; + } + + if (value[0] != 0x01) { + DBG("Unexpected ASHA version: %u", value[0]); + return; + } + + /* Device Capabilities */ + asha->right_side = (value[1] & 0x1) != 0; + asha->binaural = (value[1] & 0x2) != 0; + asha->csis_supported = (value[1] & 0x4) != 0; + /* HiSyncId: 2 byte company id, 6 byte ID shared by left and right */ + memcpy(asha->hisyncid, &value[2], 8); + /* FeatureMap */ + asha->coc_streaming_supported = (value[10] & 0x1) != 0; + /* RenderDelay */ + asha->render_delay = get_le16(&value[11]); + /* byte 13 & 14 are reserved */ + /* Codec IDs */ + asha->codec_ids = get_le16(&value[15]); + + DBG("Got ROPS: side %u, binaural %u, csis: %u, delay %u, codecs: %u", + asha->right_side, asha->binaural, asha->csis_supported, + asha->render_delay, asha->codec_ids); +} + +static void audio_status_register(uint16_t att_ecode, void *user_data) +{ + if (att_ecode) + DBG("AudioStatusPoint register failed 0x%04x", att_ecode); + else + DBG("AudioStatusPoint register succeeded"); +} + +static void audio_status_notify(uint16_t value_handle, const uint8_t *value, + uint16_t length, void *user_data) +{ + struct bt_asha *asha = user_data; + uint8_t status = *value; + /* Back these up to survive the reset paths */ + bt_asha_cb_t cb = asha->cb; + bt_asha_cb_t cb_user_data = asha->cb_user_data; + + if (asha->state == ASHA_STARTING) { + if (status == 0) { + asha->state = ASHA_STARTED; + DBG("ASHA start complete"); + } else { + bt_asha_state_reset(asha); + DBG("ASHA start failed"); + } + } else if (asha->state == ASHA_STOPPING) { + /* We reset our state, regardless */ + bt_asha_state_reset(asha); + DBG("ASHA stop %s", status == 0 ? "complete" : "failed"); + } + + if (cb) { + cb(status, cb_user_data); + asha->cb = NULL; + asha->cb_user_data = NULL; + } +} + +static void handle_characteristic(struct gatt_db_attribute *attr, + void *user_data) +{ + struct bt_asha *asha = user_data; + uint16_t value_handle; + bt_uuid_t uuid; + char uuid_str[MAX_LEN_UUID_STR]; + + if (!gatt_db_attribute_get_char_data(attr, NULL, &value_handle, NULL, + NULL, &uuid)) { + error("Failed to obtain characteristic data"); + return; + } + + bt_uuid_to_string(&uuid, uuid_str, sizeof(uuid_str)); + if (uuid_cmp(ASHA_CHRC_LE_PSM_OUT_UUID, &uuid)) { + DBG("Got chrc %s/0x%x: LE_PSM_ID", uuid_str, value_handle); + if (!bt_gatt_client_read_value(asha->client, value_handle, + read_psm, asha, NULL)) + DBG("Failed to send request to read battery level"); + } else if (uuid_cmp(ASHA_CHRC_READ_ONLY_PROPERTIES_UUID, &uuid)) { + DBG("Got chrc %s/0x%x: READ_ONLY_PROPERTIES", uuid_str, + value_handle); + if (!bt_gatt_client_read_value(asha->client, value_handle, + read_rops, asha, NULL)) + DBG("Failed to send request for readonly properties"); + } else if (uuid_cmp(ASHA_CHRC_AUDIO_CONTROL_POINT_UUID, &uuid)) { + DBG("Got chrc %s/0x%x: AUDIO_CONTROL_POINT", uuid_str, + value_handle); + /* Store this for later writes */ + asha->acp_handle = value_handle; + } else if (uuid_cmp(ASHA_CHRC_VOLUME_UUID, &uuid)) { + DBG("Got chrc %s/0x%x: VOLUME", uuid_str, value_handle); + /* Store this for later writes */ + asha->volume_handle = value_handle; + } else if (uuid_cmp(ASHA_CHRC_AUDIO_STATUS_UUID, &uuid)) { + DBG("Got chrc %s/0x%x: AUDIO_STATUS", uuid_str, value_handle); + asha->status_notify_id = + bt_gatt_client_register_notify(asha->client, + value_handle, audio_status_register, + audio_status_notify, asha, NULL); + if (!asha->status_notify_id) + DBG("Failed to send request to notify AudioStatus"); + } else { + DBG("Unsupported characteristic: %s", uuid_str); + } +} + +static void foreach_asha_service(struct gatt_db_attribute *attr, + void *user_data) +{ + struct bt_asha *asha = user_data; + + DBG("Found ASHA GATT service"); + + asha->attr = attr; + gatt_db_service_set_claimed(attr, true); + gatt_db_service_foreach_char(asha->attr, handle_characteristic, asha); +} + +bool bt_asha_probe(struct bt_asha *asha, struct gatt_db *db, + struct bt_gatt_client *client) +{ + bt_uuid_t asha_uuid; + + asha->db = gatt_db_ref(db); + asha->client = bt_gatt_client_clone(client); + + bt_uuid16_create(&asha_uuid, ASHA_SERVICE); + gatt_db_foreach_service(db, &asha_uuid, foreach_asha_service, asha); + + if (!asha->attr) { + error("ASHA attribute not found"); + bt_asha_reset(asha); + return false; + } + + return true; +} diff --git a/src/shared/asha.h b/src/shared/asha.h new file mode 100644 index 000000000..caa6b31da --- /dev/null +++ b/src/shared/asha.h @@ -0,0 +1,75 @@ +// SPDX-License-Identifier: LGPL-2.1-or-later +/* + * + * BlueZ - Bluetooth protocol stack for Linux + * + * Copyright (C) 2024 Asymptotic Inc. + * + * Author: Arun Raghavan <arun@xxxxxxxxxxxxx> + * + * + */ + +#include <stdbool.h> +#include <stdint.h> + +#include "lib/bluetooth.h" + +enum bt_asha_state_t { + ASHA_STOPPED = 0, + ASHA_STARTING, + ASHA_STARTED, + ASHA_STOPPING, +}; + +typedef void (*bt_asha_cb_t)(int status, void *data); + +struct bt_asha { + bdaddr_t addr; + struct bt_gatt_client *client; + struct gatt_db *db; + struct gatt_db_attribute *attr; + uint16_t acp_handle; + uint16_t volume_handle; + unsigned int status_notify_id; + + uint16_t psm; + bool right_side; + bool binaural; + bool csis_supported; + bool coc_streaming_supported; + uint8_t hisyncid[8]; + uint16_t render_delay; + uint16_t codec_ids; + int8_t volume; + + int fd; + uint16_t imtu, omtu; + enum bt_asha_state_t state; + bt_asha_cb_t cb; + void *cb_user_data; + int resume_id; +}; + +struct bt_asha *bt_asha_new(const bdaddr_t *addr); +void bt_asha_reset(struct bt_asha *asha); +void bt_asha_state_reset(struct bt_asha *asha); +void bt_asha_free(struct bt_asha *asha); + +uint16_t bt_asha_get_render_delay(struct bt_asha *asha); +enum bt_asha_state_t bt_asha_get_state(struct bt_asha *asha); +int bt_asha_get_fd(struct bt_asha *asha); +uint16_t bt_asha_get_omtu(struct bt_asha *asha); +uint16_t bt_asha_get_imtu(struct bt_asha *asha); + +int bt_asha_connect_socket(struct bt_asha *asha); +unsigned int bt_asha_start(struct bt_asha *asha, bt_asha_cb_t cb, + void *user_data); +unsigned int bt_asha_stop(struct bt_asha *asha, bt_asha_cb_t cb, + void *user_data); + +int8_t bt_asha_get_volume(struct bt_asha *asha); +bool bt_asha_set_volume(struct bt_asha *asha, int8_t volume); + +bool bt_asha_probe(struct bt_asha *asha, struct gatt_db *db, + struct bt_gatt_client *client); -- 2.45.1
