nimble/audio: Add LE Audio event listener and BASE parser

nimble/host/audio/include/host/audio/ble_audio.h

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+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+#ifndef H_BLE_AUDIO_
+#define H_BLE_AUDIO_
+
+#include <stdint.h>
+#include <sys/queue.h>
+
+#include "host/ble_audio_common.h"
+
+/** @brief Public Broadcast Announcement features bits */
+enum ble_audio_pub_bcst_announcement_feat {
+    /** Broadcast Stream Encryption */
+    BLE_AUDIO_PUB_BCST_ANNOUNCEMENT_FEAT_ENCRYPTION = 1 << 0,
+
+    /** Standard Quality Public Broadcast Audio */
+    BLE_AUDIO_PUB_BCST_ANNOUNCEMENT_FEAT_SQ = 1 << 1,
+
+    /** High Quality Public Broadcast Audio */
+    BLE_AUDIO_PUB_BCST_ANNOUNCEMENT_FEAT_HQ = 1 << 2,
+};
+
+/** @brief Public Broadcast Announcement structure */
+struct ble_audio_pub_bcst_announcement {
+    /** Public Broadcast Announcement features bitfield */
+    enum ble_audio_pub_bcst_announcement_feat features;
+
+    /** Metadata length */
+    uint8_t metadata_len;
+
+    /** Metadata */
+    const uint8_t *metadata;
+};
+
+struct ble_audio_bcst_name {
+    /** Broadcast Name length */
+    uint8_t name_len;
+
+    /** Broadcast Name */
+    const char *name;
+};
+
+/**
+ * @defgroup ble_audio_events Bluetooth Low Energy Audio Events
+ * @{
+ */
+
+/** BLE Audio event: Broadcast Announcement */
+#define BLE_AUDIO_EVENT_BCST_ANNOUNCEMENT               0
+
+/** @} */
+
+/** @brief Broadcast Announcement */
+struct ble_audio_event_bcst_announcement {
+    /** Extended advertising report */
+    const struct ble_gap_ext_disc_desc *ext_disc;
+
+    /** Broadcast ID */
+    uint32_t broadcast_id;
+
+    /** Additional service data included in Broadcast Audio Announcement */
+    const uint8_t *svc_data;
+
+    /** Additional service data length  */
+    uint16_t svc_data_len;
+
+    /** Optional Public Broadcast Announcement data */
+    struct ble_audio_pub_bcst_announcement *pub_announcement_data;
+
+    /** Optional Broadcast Name */
+    struct ble_audio_bcst_name *name;
+};
+
+/**
+ * Represents a BLE Audio related event. When such an event occurs, the host
+ * notifies the application by passing an instance of this structure to an
+ * application-specified callback.
+ */
+struct ble_audio_event {
+    /**
+     * Indicates the type of BLE Audio event that occurred. This is one of the
+     * BLE_AUDIO_EVENT codes.
+     */
+    uint8_t type;
+
+    /**
+     * A discriminated union containing additional details concerning the event.
+     * The 'type' field indicates which member of the union is valid.
+     */
+    union {
+        /**
+         * @ref BLE_AUDIO_EVENT_BCST_ANNOUNCEMENT
+         *
+         * Represents a received Broadcast Announcement.
+         */
+        struct ble_audio_event_bcst_announcement bcst_announcement;
+    };
+};
+
+/** Callback function type for handling BLE Audio events. */
+typedef int ble_audio_event_fn(struct ble_audio_event *event, void *arg);
+
+/**
+ * Event listener structure
+ *
+ * This should be used as an opaque structure and not modified manually.
+ */
+struct ble_audio_event_listener {
+    /** The function to call when a BLE Audio event occurs. */
+    ble_audio_event_fn *fn;
+
+    /** An optional argument to pass to the event handler function. */
+    void *arg;
+
+    /** Singly-linked list entry. */
+    SLIST_ENTRY(ble_audio_event_listener) next;
+};
+
+/**
+ * Registers listener for BLE Audio events
+ *
+ * On success listener structure will be initialized automatically and does not
+ * need to be initialized prior to calling this function. To change callback
+ * and/or argument unregister listener first and register it again.
+ *
+ * @param[in] listener          Listener structure
+ * @param[in] event_mask        Optional event mask
+ * @param[in] fn                Callback function
+ * @param[in] arg               Optional callback argument
+ *
+ * @return                      0 on success
+ *                              BLE_HS_EINVAL if no callback is specified
+ *                              BLE_HS_EALREADY if listener is already registered
+ */
+int ble_audio_event_listener_register(struct ble_audio_event_listener *listener,
+                                      ble_audio_event_fn *fn, void *arg);
+
+/**
+ * Unregisters listener for BLE Audio events
+ *
+ * @param[in] listener          Listener structure
+ *
+ * @return                      0 on success
+ *                              BLE_HS_ENOENT if listener was not registered
+ */
+int ble_audio_event_listener_unregister(struct ble_audio_event_listener *listener);
+
+/**
+ * BASE iterator
+ *
+ * The iterator structure used by @ref ble_audio_base_subgroup_iter and
+ * @ble_audio_base_bis_iter functions to iterate the BASE Level 2 and 3 elements
+ * (Subgroups and BISes).
+ * This should be used as an opaque structure and not modified manually.
+ *
+ * Example:
+ * @code{.c}
+ * struct ble_audio_base_iter subgroup_iter;
+ * struct ble_audio_base_iter bis_iter;
+ * struct ble_audio_base_group group;
+ * struct ble_audio_base_subgroup subgroup;
+ * struct ble_audio_base_bis bis;
+ *
+ * rc = ble_audio_base_parse(data, data_size, &group, &subgroup_iter);
+ * if (rc == 0) {
+ *     for (uint8_t i = 0; i < group->num_subgroups; i++) {
+ *         rc = ble_audio_base_subgroup_iter(&subgroup_iter, &subgroup, &bis_iter);
+ *         if (rc == 0) {
+ *             for (uint8_t j = 0; j < subgroup->num_bis; j++) {
+ *                 rc = ble_audio_base_bis_iter(&bis_iter, &bis);
+ *                 if (rc == 0) {
+ *                     foo(&group, &subgroup, &bis);
+ *                 }
+ *             }
+ *         }
+ *     }
+ * }
+ * @endcode
+ */
+struct ble_audio_base_iter {
+    /** Data pointer */
+    const uint8_t *data;
+
+    /** Base length */
+    uint8_t buf_len;
+
+    /** Original BASE pointer */
+    const uint8_t *buf;
+
+    /** Remaining number of elements */
+    uint8_t num_elements;
+};
+
+/** @brief Broadcast Audio Source Endpoint Group structure */
+struct ble_audio_base_group {
+    /** Presentation Delay */
+    uint32_t presentation_delay;
+
+    /** Number of subgroups */
+    uint8_t num_subgroups;
+};
+
+/**
+ * Parse the BASE received from Basic Audio Announcement data.
+ *
+ * @param[in] data              Pointer to the BASE data buffer to parse.
+ * @param[in] data_len          Length of the BASE data buffer.
+ * @param[out] group            Group object.
+ * @param[out] subgroup_iter    Subgroup iterator object.
+ *
+ * @return                      0 on success; nonzero on failure.
+ */
+int ble_audio_base_parse(const uint8_t *data, uint8_t data_len,
+                         struct ble_audio_base_group *group,
+                         struct ble_audio_base_iter *subgroup_iter);
+
+/** @brief Broadcast Audio Source Endpoint Subgroup structure */
+struct ble_audio_base_subgroup {
+    /** Codec information for the subgroup */
+    struct ble_audio_codec_id codec_id;
+
+    /** Length of the Codec Specific Configuration for the subgroup */
+    uint8_t codec_spec_config_len;
+
+    /** Codec Specific Configuration for the subgroup */
+    const uint8_t *codec_spec_config;
+
+    /** Length of the Metadata for the subgroup */
+    uint8_t metadata_len;
+
+    /** Series of LTV structures containing Metadata */
+    const uint8_t *metadata;
+
+    /** Number of BISes in the subgroup */
+    uint8_t num_bis;
+};
+
+/**
+ * @brief Basic Audio Announcement Subgroup information
+ *
+ * @param[in] subgroup_iter     Subgroup iterator object.
+ * @param[out] subgroup         Subgroup object.
+ * @param[out] bis_iter         BIS iterator object.
+ *
+ * @return                      0 on success;
+ *                              A non-zero value on failure.
+ */
+int ble_audio_base_subgroup_iter(struct ble_audio_base_iter *subgroup_iter,
+                                 struct ble_audio_base_subgroup *subgroup,
+                                 struct ble_audio_base_iter *bis_iter);
+
+/** @brief Broadcast Audio Source Endpoint BIS structure */
+struct ble_audio_base_bis {
+    /** BIS_index value for the BIS */
+    uint8_t index;
+
+    /** Length of the Codec Specific Configuration for the BIS */
+    uint8_t codec_spec_config_len;
+
+    /** Codec Specific Configuration for the BIS */
+    const uint8_t *codec_spec_config;
+};
+
+/**
+ * @brief Basic Audio Announcement Subgroup information
+ *
+ * @param[in] bis_iter          BIS iterator object.
+ * @param[out] bis              BIS object.
+ *
+ * @return                      0 on success;
+ *                              A non-zero value on failure.
+ */
+int ble_audio_base_bis_iter(struct ble_audio_base_iter *bis_iter,
+                            struct ble_audio_base_bis *bis);
+
+#endif /* H_BLE_AUDIO_ */

nimble/host/audio/pkg.yml

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+#
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#  http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+#
+
+pkg.name: nimble/host/audio
+pkg.description: Bluetooth LE Audio
+pkg.author: "Apache Mynewt <dev@mynewt.apache.org>"
+pkg.homepage: "http://mynewt.apache.org/"
+pkg.experimental: 1
+pkg.keywords:
+    - ble
+    - bluetooth
+    - audio
+
+pkg.deps:
+    - nimble
+    - nimble/host