1 /** @file 2 * @brief Audio Video Control Transport Protocol internal header. 3 */ 4 5 /* 6 * Copyright (c) 2015-2016 Intel Corporation 7 * Copyright (C) 2024 Xiaomi Corporation 8 * 9 * SPDX-License-Identifier: Apache-2.0 10 */ 11 12 #define BT_L2CAP_PSM_AVCTP 0x0017 13 14 typedef enum __packed { 15 BT_AVCTP_IPID_NONE = 0b0, 16 BT_AVCTP_IPID_INVALID = 0b1, 17 } bt_avctp_ipid_t; 18 19 typedef enum __packed { 20 BT_AVCTP_CMD = 0b0, 21 BT_AVCTP_RESPONSE = 0b1, 22 } bt_avctp_cr_t; 23 24 typedef enum __packed { 25 BT_AVCTP_PKT_TYPE_SINGLE = 0b00, 26 BT_AVCTP_PKT_TYPE_START = 0b01, 27 BT_AVCTP_PKT_TYPE_CONTINUE = 0b10, 28 BT_AVCTP_PKT_TYPE_END = 0b11, 29 } bt_avctp_pkt_type_t; 30 31 struct bt_avctp_header { 32 uint8_t byte0; /** [7:4]: Transaction label, [3:2]: Packet_type, [1]: C/R, [0]: IPID */ 33 uint16_t pid; /** Profile Identifier */ 34 } __packed; 35 36 /** Transaction label provided by the application and is replicated by the sender of the message in 37 * each packet of the sequence. It isused at the receiver side to identify packets that belong to 38 * the same message. 39 */ 40 #define BT_AVCTP_HDR_GET_TRANSACTION_LABLE(hdr) FIELD_GET(GENMASK(7, 4), ((hdr)->byte0)) 41 /** Set to zero (00) to indicate that the command/response message is transmitted in a single L2CAP 42 * packet. Alternatively, set to (01) for start, (10) for continue, or (11) for end packet. 43 */ 44 #define BT_AVCTP_HDR_GET_PACKET_TYPE(hdr) FIELD_GET(GENMASK(3, 2), ((hdr)->byte0)) 45 /** Indicates whether the messageconveys a command frame (0) or a response frame (1). */ 46 #define BT_AVCTP_HDR_GET_CR(hdr) FIELD_GET(BIT(1), ((hdr)->byte0)) 47 /** The IPID bit is set in a response message to indicate an invalid Profile Identifier received in 48 * the command message of the same transaction; otherwise this bit is set to zero. In command 49 * messages this bit is set to zero. This field is only present in the start packet of the message. 50 */ 51 #define BT_AVCTP_HDR_GET_IPID(hdr) FIELD_GET(BIT(0), ((hdr)->byte0)) 52 53 /** Transaction label provided by the application and is replicated by the sender of the message in 54 * each packet of the sequence. It isused at the receiver side to identify packets that belong to 55 * the same message. 56 */ 57 #define BT_AVCTP_HDR_SET_TRANSACTION_LABLE(hdr, tl) \ 58 (hdr)->byte0 = (((hdr)->byte0) & ~GENMASK(7, 4)) | FIELD_PREP(GENMASK(7, 4), (tl)) 59 /** Set to zero (00) to indicate that the command/response message is transmitted in a single L2CAP 60 * packet. Alternatively, set to (01) for start, (10) for continue, or (11) for end packet. 61 */ 62 #define BT_AVCTP_HDR_SET_PACKET_TYPE(hdr, packet_type) \ 63 (hdr)->byte0 = (((hdr)->byte0) & ~GENMASK(3, 2)) | FIELD_PREP(GENMASK(3, 2), (packet_type)) 64 /** Indicates whether the messageconveys a command frame (0) or a response frame (1). */ 65 #define BT_AVCTP_HDR_SET_CR(hdr, cr) \ 66 (hdr)->byte0 = (((hdr)->byte0) & ~BIT(1)) | FIELD_PREP(BIT(1), (cr)) 67 /** The IPID bit is set in a response message to indicate an invalid Profile Identifier received in 68 * the command message of the same transaction; otherwise this bit is set to zero. In command 69 * messages this bit is set to zero. This field is only present in the start packet of the message. 70 */ 71 #define BT_AVCTP_HDR_SET_IPID(hdr, ipid) \ 72 (hdr)->byte0 = (((hdr)->byte0) & ~BIT(0)) | FIELD_PREP(BIT(0), (ipid)) 73 74 struct bt_avctp; 75 76 struct bt_avctp_ops_cb { 77 void (*connected)(struct bt_avctp *session); 78 void (*disconnected)(struct bt_avctp *session); 79 int (*recv)(struct bt_avctp *session, struct net_buf *buf); 80 }; 81 82 struct bt_avctp { 83 struct bt_l2cap_br_chan br_chan; 84 const struct bt_avctp_ops_cb *ops; 85 }; 86 87 struct bt_avctp_event_cb { 88 int (*accept)(struct bt_conn *conn, struct bt_avctp **session); 89 }; 90 91 /* Initialize AVCTP layer*/ 92 int bt_avctp_init(void); 93 94 /* Application register with AVCTP layer */ 95 int bt_avctp_register(const struct bt_avctp_event_cb *cb); 96 97 /* AVCTP connect */ 98 int bt_avctp_connect(struct bt_conn *conn, struct bt_avctp *session); 99 100 /* AVCTP disconnect */ 101 int bt_avctp_disconnect(struct bt_avctp *session); 102 103 /* Create AVCTP PDU */ 104 struct net_buf *bt_avctp_create_pdu(struct bt_avctp *session, bt_avctp_cr_t cr, 105 bt_avctp_pkt_type_t pkt_type, bt_avctp_ipid_t ipid, 106 uint8_t *tid, uint16_t pid); 107 108 /* Send AVCTP PDU */ 109 int bt_avctp_send(struct bt_avctp *session, struct net_buf *buf); 110
