/* * Copyright (C) 2014 BlueKitchen GmbH * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the copyright holders nor the names of * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * 4. Any redistribution, use, or modification is done solely for * personal benefit and not for any commercial purpose or for * monetary gain. * * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * Please inquire about commercial licensing options at * contact@bluekitchen-gmbh.com * */ #define BTSTACK_FILE__ "le_data_channel_server.c" // ***************************************************************************** /* EXAMPLE_START(le_data_channel): LE Data Channel Server - Receive data via L2CAP * * @text iOS 11 and newer supports LE Data Channels for fast transfer via LE * [https://github.com/bluekitchen/CBL2CAPChannel-Demo](Basic iOS example on GitHub) */ // ***************************************************************************** #include #include #include #include #include #include "btstack.h" #include "le_data_channel_server.h" // #define TEST_STREAM_DATA #define TEST_PACKET_SIZE 1000 #define REPORT_INTERVAL_MS 3000 #define MAX_NR_CONNECTIONS 3 const uint16_t TSPX_le_psm = 0x25; static void packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size); const uint8_t adv_data[] = { // Flags general discoverable, BR/EDR not supported 0x02, 0x01, 0x06, // Name 0x10, 0x09, 'L', 'E', ' ', 'D', 'a', 't', 'a', ' ', 'C', 'h', 'a', 'n', 'n', 'e', 'l', }; const uint8_t adv_data_len = sizeof(adv_data); static btstack_packet_callback_registration_t hci_event_callback_registration; // support for multiple clients typedef struct { char name; hci_con_handle_t connection_handle; uint16_t cid; int counter; char test_data[TEST_PACKET_SIZE]; int test_data_len; uint32_t test_data_sent; uint32_t test_data_start; } le_data_channel_connection_t; static le_data_channel_connection_t le_data_channel_connection; static uint16_t initial_credits = L2CAP_LE_AUTOMATIC_CREDITS; static uint8_t data_channel_buffer[TEST_PACKET_SIZE]; /* @section Main Application Setup * * @text Listing MainConfiguration shows main application code. * It initializes L2CAP, the Security Manager, and configures the ATT Server with the pre-compiled * ATT Database generated from $le_data_channel.gatt$. Finally, it configures the advertisements * and boots the Bluetooth stack. */ /* LISTING_START(MainConfiguration): Init L2CAP, SM, ATT Server, and enable advertisements */ static void le_data_channel_setup(void){ l2cap_init(); // setup le device db le_device_db_init(); // setup SM: Display only sm_init(); // setup ATT server: iOS disconnects if ATT MTU Exchange fails att_server_init(profile_data, NULL, NULL); // register for HCI events hci_event_callback_registration.callback = &packet_handler; hci_add_event_handler(&hci_event_callback_registration); l2cap_register_packet_handler(&packet_handler); // le data channel setup l2cap_le_register_service(&packet_handler, TSPX_le_psm, LEVEL_0); // setup advertisements uint16_t adv_int_min = 0x0030; uint16_t adv_int_max = 0x0030; uint8_t adv_type = 0; bd_addr_t null_addr; memset(null_addr, 0, 6); gap_advertisements_set_params(adv_int_min, adv_int_max, adv_type, 0, null_addr, 0x07, 0x00); gap_advertisements_set_data(adv_data_len, (uint8_t*) adv_data); gap_advertisements_enable(1); } /* LISTING_END */ /* * @section Track throughput * @text We calculate the throughput by setting a start time and measuring the amount of * data sent. After a configurable REPORT_INTERVAL_MS, we print the throughput in kB/s * and reset the counter and start time. */ /* LISTING_START(tracking): Tracking throughput */ static void test_reset(le_data_channel_connection_t * context){ context->test_data_start = btstack_run_loop_get_time_ms(); context->test_data_sent = 0; } static void test_track_data(le_data_channel_connection_t * context, int bytes_transferred){ context->test_data_sent += bytes_transferred; // evaluate uint32_t now = btstack_run_loop_get_time_ms(); uint32_t time_passed = now - context->test_data_start; if (time_passed < REPORT_INTERVAL_MS) return; // print speed int bytes_per_second = context->test_data_sent * 1000 / time_passed; printf("%c: %"PRIu32" bytes sent-> %u.%03u kB/s\n", context->name, context->test_data_sent, bytes_per_second / 1000, bytes_per_second % 1000); // restart context->test_data_start = now; context->test_data_sent = 0; } /* LISTING_END(tracking): Tracking throughput */ #ifdef TEST_STREAM_DATA /* LISTING_END */ /* * @section Streamer * * @text The streamer function checks if notifications are enabled and if a notification can be sent now. * It creates some test data - a single letter that gets increased every time - and tracks the data sent. */ /* LISTING_START(streamer): Streaming code */ static void streamer(void){ if (le_data_channel_connection.cid == 0) return; // create test data le_data_channel_connection.counter++; if (le_data_channel_connection.counter > 'Z') le_data_channel_connection.counter = 'A'; memset(le_data_channel_connection.test_data, le_data_channel_connection.counter, le_data_channel_connection.test_data_len); // send l2cap_le_send_data(le_data_channel_connection.cid, (uint8_t *) le_data_channel_connection.test_data, le_data_channel_connection.test_data_len); // track test_track_data(&le_data_channel_connection, le_data_channel_connection.test_data_len); // request another packet l2cap_le_request_can_send_now_event(le_data_channel_connection.cid); } /* LISTING_END */ #endif /* * @section Packet Handler * * @text The packet handler is used to stop the notifications and reset the MTU on connect * It would also be a good place to request the connection parameter update as indicated * in the commented code block. */ /* LISTING_START(packetHandler): Packet Handler */ static void packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ UNUSED(channel); bd_addr_t event_address; uint16_t psm; uint16_t cid; uint16_t conn_interval; hci_con_handle_t handle; switch (packet_type) { case HCI_EVENT_PACKET: switch (hci_event_packet_get_type(packet)) { case BTSTACK_EVENT_STATE: // BTstack activated, get started if (btstack_event_state_get_state(packet) == HCI_STATE_WORKING) { printf("To start the streaming, please run the le_data_channel_client example on other device.\n"); } break; case HCI_EVENT_DISCONNECTION_COMPLETE: // free connection printf("%c: Disconnect, reason %02x\n", le_data_channel_connection.name, hci_event_disconnection_complete_get_reason(packet)); le_data_channel_connection.connection_handle = HCI_CON_HANDLE_INVALID; break; case HCI_EVENT_LE_META: switch (hci_event_le_meta_get_subevent_code(packet)) { case HCI_SUBEVENT_LE_CONNECTION_COMPLETE: // print connection parameters (without using float operations) conn_interval = hci_subevent_le_connection_complete_get_conn_interval(packet); printf("%c: Connection Interval: %u.%02u ms\n", le_data_channel_connection.name, conn_interval * 125 / 100, 25 * (conn_interval & 3)); printf("%c: Connection Latency: %u\n", le_data_channel_connection.name, hci_subevent_le_connection_complete_get_conn_latency(packet)); // min con interval 15 ms - supported from iOS 11 gap_request_connection_parameter_update(le_data_channel_connection.connection_handle, 12, 12, 0, 0x0048); printf("Connected, requesting conn param update for handle 0x%04x\n", le_data_channel_connection.connection_handle); // test_reset(&le_data_channel_connection); break; case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE: // print connection parameters (without using float operations) conn_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet); printf("LE Connection Update:\n"); printf("%c: Connection Interval: %u.%02u ms\n", le_data_channel_connection.name, conn_interval * 125 / 100, 25 * (conn_interval & 3)); printf("%c: Connection Latency: %u\n", le_data_channel_connection.name, hci_subevent_le_connection_update_complete_get_conn_latency(packet)); break; } break; case L2CAP_EVENT_CONNECTION_PARAMETER_UPDATE_RESPONSE: printf("L2CAP Connection Parameter Update Complete, response: %x\n", l2cap_event_connection_parameter_update_response_get_result(packet)); break; // LE Data Channels case L2CAP_EVENT_LE_INCOMING_CONNECTION: psm = l2cap_event_le_incoming_connection_get_psm(packet); cid = l2cap_event_le_incoming_connection_get_local_cid(packet); if (psm != TSPX_le_psm) break; printf("L2CAP: Accepting incoming LE connection request for 0x%02x, PSM %02x\n", cid, psm); l2cap_le_accept_connection(cid, data_channel_buffer, sizeof(data_channel_buffer), initial_credits); break; case L2CAP_EVENT_LE_CHANNEL_OPENED: // inform about new l2cap connection l2cap_event_le_channel_opened_get_address(packet, event_address); psm = l2cap_event_le_channel_opened_get_psm(packet); cid = l2cap_event_le_channel_opened_get_local_cid(packet); handle = l2cap_event_le_channel_opened_get_handle(packet); if (packet[2] == 0) { printf("L2CAP: LE Data Channel successfully opened: %s, handle 0x%02x, psm 0x%02x, local cid 0x%02x, remote cid 0x%02x\n", bd_addr_to_str(event_address), handle, psm, cid, little_endian_read_16(packet, 15)); // setup new le_data_channel_connection.counter = 'A'; le_data_channel_connection.cid = cid; le_data_channel_connection.connection_handle = handle; le_data_channel_connection.test_data_len = btstack_min(l2cap_event_le_channel_opened_get_remote_mtu(packet), sizeof(le_data_channel_connection.test_data)); printf("Test packet size: %u\n", le_data_channel_connection.test_data_len); test_reset(&le_data_channel_connection); #ifdef TEST_STREAM_DATA l2cap_le_request_can_send_now_event(le_data_channel_connection.cid); #endif } else { printf("L2CAP: LE Data Channel connection to device %s failed. status code %u\n", bd_addr_to_str(event_address), packet[2]); } break; case L2CAP_EVENT_LE_CHANNEL_CLOSED: printf("L2CAP: LE Data Channel closed\n"); le_data_channel_connection.cid = 0; break; #ifdef TEST_STREAM_DATA case L2CAP_EVENT_LE_CAN_SEND_NOW: streamer(); break; #endif default: break; } break; case L2CAP_DATA_PACKET: test_track_data(&le_data_channel_connection, size); break; default: break; } } int btstack_main(void); int btstack_main(void) { le_data_channel_setup(); // turn on! hci_power_control(HCI_POWER_ON); return 0; } /* EXAMPLE_END */