1 /* 2 * Copyright (C) 2014 BlueKitchen GmbH 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the copyright holders nor the names of 14 * contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 4. Any redistribution, use, or modification is done solely for 17 * personal benefit and not for any commercial purpose or for 18 * monetary gain. 19 * 20 * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL BLUEKITCHEN 24 * GMBH OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 27 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 28 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 29 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 30 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * Please inquire about commercial licensing options at 34 * [email protected] 35 * 36 */ 37 38 #define BTSTACK_FILE__ "gatt_streamer.c" 39 40 // ***************************************************************************** 41 /* EXAMPLE_START(le_streamer): LE Streamer - Stream data over GATT. 42 * 43 * @text All newer operating systems provide GATT Client functionality. 44 * This example shows how to get a maximal throughput via BLE: 45 * - send whenever possible, 46 * - use the max ATT MTU. 47 * 48 * @text In theory, we should also update the connection parameters, but we already get 49 * a connection interval of 30 ms and there's no public way to use a shorter 50 * interval with iOS (if we're not implementing an HID device). 51 * 52 * @text Note: To start the streaming, run the example. 53 * On remote device use some GATT Explorer, e.g. LightBlue, BLExplr to enable notifications. 54 */ 55 // ***************************************************************************** 56 57 #include <inttypes.h> 58 #include <stdint.h> 59 #include <stdio.h> 60 #include <stdlib.h> 61 #include <string.h> 62 63 #include "btstack.h" 64 65 // le_streamer.gatt contains the declaration of the provided GATT Services + Characteristics 66 // le_streamer.h contains the binary representation of le_streamer.gatt 67 // it is generated by the build system by calling: $BTSTACK_ROOT/tool/compile_gatt.py le_streamer.gatt le_streamer.h 68 // it needs to be regenerated when the GATT Database declared in le_streamer.gatt file is modified 69 #include "gatt_streamer_server.h" 70 71 #define REPORT_INTERVAL_MS 3000 72 #define MAX_NR_CONNECTIONS 3 73 74 75 static void hci_packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size); 76 static void att_packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size); 77 static int att_write_callback(hci_con_handle_t con_handle, uint16_t att_handle, uint16_t transaction_mode, uint16_t offset, uint8_t *buffer, uint16_t buffer_size); 78 static void streamer(void); 79 80 const uint8_t adv_data[] = { 81 // Flags general discoverable, BR/EDR not supported 82 0x02, BLUETOOTH_DATA_TYPE_FLAGS, 0x06, 83 // Name 84 0x0c, BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME, 'L', 'E', ' ', 'S', 't', 'r', 'e', 'a', 'm', 'e', 'r', 85 // Incomplete List of 16-bit Service Class UUIDs -- FF10 - only valid for testing! 86 0x03, BLUETOOTH_DATA_TYPE_INCOMPLETE_LIST_OF_16_BIT_SERVICE_CLASS_UUIDS, 0x10, 0xff, 87 }; 88 const uint8_t adv_data_len = sizeof(adv_data); 89 90 static btstack_packet_callback_registration_t hci_event_callback_registration; 91 92 // support for multiple clients 93 typedef struct { 94 char name; 95 int le_notification_enabled; 96 uint16_t value_handle; 97 hci_con_handle_t connection_handle; 98 int counter; 99 char test_data[200]; 100 int test_data_len; 101 uint32_t test_data_sent; 102 uint32_t test_data_start; 103 } le_streamer_connection_t; 104 static le_streamer_connection_t le_streamer_connections[MAX_NR_CONNECTIONS]; 105 106 // round robin sending 107 static int connection_index; 108 109 #ifdef ENABLE_GATT_OVER_CLASSIC 110 static uint8_t gatt_service_buffer[70]; 111 #endif 112 113 static void init_connections(void){ 114 // track connections 115 int i; 116 for (i=0;i<MAX_NR_CONNECTIONS;i++){ 117 le_streamer_connections[i].connection_handle = HCI_CON_HANDLE_INVALID; 118 le_streamer_connections[i].name = 'A' + i; 119 } 120 } 121 122 static le_streamer_connection_t * connection_for_conn_handle(hci_con_handle_t conn_handle){ 123 int i; 124 for (i=0;i<MAX_NR_CONNECTIONS;i++){ 125 if (le_streamer_connections[i].connection_handle == conn_handle) return &le_streamer_connections[i]; 126 } 127 return NULL; 128 } 129 130 static void next_connection_index(void){ 131 connection_index++; 132 if (connection_index == MAX_NR_CONNECTIONS){ 133 connection_index = 0; 134 } 135 } 136 137 /* @section Main Application Setup 138 * 139 * @text Listing MainConfiguration shows main application code. 140 * It initializes L2CAP, the Security Manager, and configures the ATT Server with the pre-compiled 141 * ATT Database generated from $le_streamer.gatt$. Finally, it configures the advertisements 142 * and boots the Bluetooth stack. 143 */ 144 145 /* LISTING_START(MainConfiguration): Init L2CAP, SM, ATT Server, and enable advertisements */ 146 147 static void le_streamer_setup(void){ 148 149 l2cap_init(); 150 151 // setup le device db 152 le_device_db_init(); 153 154 // setup SM: Display only 155 sm_init(); 156 157 #ifdef ENABLE_GATT_OVER_CLASSIC 158 // init SDP, create record for GATT and register with SDP 159 sdp_init(); 160 memset(gatt_service_buffer, 0, sizeof(gatt_service_buffer)); 161 gatt_create_sdp_record(gatt_service_buffer, 0x10001, ATT_SERVICE_GATT_SERVICE_START_HANDLE, ATT_SERVICE_GATT_SERVICE_END_HANDLE); 162 sdp_register_service(gatt_service_buffer); 163 printf("SDP service record size: %u\n", de_get_len(gatt_service_buffer)); 164 165 // configure Classic GAP 166 gap_set_local_name("GATT Streamer BR/EDR 00:00:00:00:00:00"); 167 gap_ssp_set_io_capability(SSP_IO_CAPABILITY_DISPLAY_YES_NO); 168 gap_discoverable_control(1); 169 #endif 170 171 // setup ATT server 172 att_server_init(profile_data, NULL, att_write_callback); 173 174 // register for HCI events 175 hci_event_callback_registration.callback = &hci_packet_handler; 176 hci_add_event_handler(&hci_event_callback_registration); 177 178 // register for ATT events 179 att_server_register_packet_handler(att_packet_handler); 180 181 // setup advertisements 182 uint16_t adv_int_min = 0x0030; 183 uint16_t adv_int_max = 0x0030; 184 uint8_t adv_type = 0; 185 bd_addr_t null_addr; 186 memset(null_addr, 0, 6); 187 gap_advertisements_set_params(adv_int_min, adv_int_max, adv_type, 0, null_addr, 0x07, 0x00); 188 gap_advertisements_set_data(adv_data_len, (uint8_t*) adv_data); 189 gap_advertisements_enable(1); 190 191 // init client state 192 init_connections(); 193 } 194 /* LISTING_END */ 195 196 /* 197 * @section Track throughput 198 * @text We calculate the throughput by setting a start time and measuring the amount of 199 * data sent. After a configurable REPORT_INTERVAL_MS, we print the throughput in kB/s 200 * and reset the counter and start time. 201 */ 202 203 /* LISTING_START(tracking): Tracking throughput */ 204 205 static void test_reset(le_streamer_connection_t * context){ 206 context->test_data_start = btstack_run_loop_get_time_ms(); 207 context->test_data_sent = 0; 208 } 209 210 static void test_track_sent(le_streamer_connection_t * context, int bytes_sent){ 211 context->test_data_sent += bytes_sent; 212 // evaluate 213 uint32_t now = btstack_run_loop_get_time_ms(); 214 uint32_t time_passed = now - context->test_data_start; 215 if (time_passed < REPORT_INTERVAL_MS) return; 216 // print speed 217 int bytes_per_second = context->test_data_sent * 1000 / time_passed; 218 printf("%c: %"PRIu32" bytes sent-> %u.%03u kB/s\n", context->name, context->test_data_sent, bytes_per_second / 1000, bytes_per_second % 1000); 219 220 // restart 221 context->test_data_start = now; 222 context->test_data_sent = 0; 223 } 224 /* LISTING_END(tracking): Tracking throughput */ 225 226 /* 227 * @section HCI Packet Handler 228 * 229 * @text The packet handler is used track incoming connections and to stop notifications on disconnect 230 * It is also a good place to request the connection parameter update as indicated 231 * in the commented code block. 232 */ 233 234 /* LISTING_START(hciPacketHandler): Packet Handler */ 235 static void hci_packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 236 UNUSED(channel); 237 UNUSED(size); 238 239 uint16_t conn_interval; 240 hci_con_handle_t con_handle; 241 switch (packet_type) { 242 case HCI_EVENT_PACKET: 243 switch (hci_event_packet_get_type(packet)) { 244 case BTSTACK_EVENT_STATE: 245 // BTstack activated, get started 246 if (btstack_event_state_get_state(packet) == HCI_STATE_WORKING) { 247 printf("To start the streaming, please run the le_streamer_client example on other device, or use some GATT Explorer, e.g. LightBlue, BLExplr.\n"); 248 } 249 break; 250 case HCI_EVENT_DISCONNECTION_COMPLETE: 251 con_handle = hci_event_disconnection_complete_get_connection_handle(packet); 252 printf("- LE Connection %04x: disconnect, reason %02x\n", con_handle, hci_event_disconnection_complete_get_reason(packet)); 253 break; 254 case HCI_EVENT_META_GAP: 255 // wait for connection complete 256 switch (hci_event_gap_meta_get_subevent_code(packet)) { 257 case GAP_SUBEVENT_LE_CONNECTION_COMPLETE: 258 // print connection parameters (without using float operations) 259 con_handle = gap_subevent_le_connection_complete_get_connection_handle(packet); 260 conn_interval = gap_subevent_le_connection_complete_get_conn_interval(packet); 261 printf("- LE Connection %04x: connected - connection interval %u.%02u ms, latency %u\n", con_handle, conn_interval * 125 / 100, 262 25 * (conn_interval & 3), gap_subevent_le_connection_complete_get_conn_latency(packet)); 263 // request min con interval 15 ms for iOS 11+ 264 // printf("- LE Connection %04x: request 15 ms connection interval\n", con_handle); 265 // gap_request_connection_parameter_update(con_handle, 12, 12, 0, 0x0048); 266 break; 267 default: 268 break; 269 } 270 break; 271 case HCI_EVENT_LE_META: 272 switch (hci_event_le_meta_get_subevent_code(packet)) { 273 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE: 274 // print connection parameters (without using float operations) 275 con_handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet); 276 conn_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet); 277 printf("- LE Connection %04x: connection update - connection interval %u.%02u ms, latency %u\n", con_handle, conn_interval * 125 / 100, 278 25 * (conn_interval & 3), hci_subevent_le_connection_update_complete_get_conn_latency(packet)); 279 break; 280 default: 281 break; 282 } 283 break; 284 default: 285 break; 286 } 287 } 288 } 289 290 /* LISTING_END */ 291 292 /* 293 * @section ATT Packet Handler 294 * 295 * @text The packet handler is used to track the ATT MTU Exchange and trigger ATT send 296 */ 297 298 /* LISTING_START(attPacketHandler): Packet Handler */ 299 static void att_packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 300 UNUSED(channel); 301 UNUSED(size); 302 303 int mtu; 304 le_streamer_connection_t * context; 305 switch (packet_type) { 306 case HCI_EVENT_PACKET: 307 switch (hci_event_packet_get_type(packet)) { 308 case ATT_EVENT_CONNECTED: 309 // setup new 310 context = connection_for_conn_handle(HCI_CON_HANDLE_INVALID); 311 if (!context) break; 312 context->counter = 'A'; 313 context->connection_handle = att_event_connected_get_handle(packet); 314 context->test_data_len = btstack_min(att_server_get_mtu(context->connection_handle) - 3, sizeof(context->test_data)); 315 printf("%c: ATT connected, handle %04x, test data len %u\n", context->name, context->connection_handle, context->test_data_len); 316 break; 317 case ATT_EVENT_MTU_EXCHANGE_COMPLETE: 318 mtu = att_event_mtu_exchange_complete_get_MTU(packet) - 3; 319 context = connection_for_conn_handle(att_event_mtu_exchange_complete_get_handle(packet)); 320 if (!context) break; 321 context->test_data_len = btstack_min(mtu - 3, sizeof(context->test_data)); 322 printf("%c: ATT MTU = %u => use test data of len %u\n", context->name, mtu, context->test_data_len); 323 break; 324 case ATT_EVENT_CAN_SEND_NOW: 325 streamer(); 326 break; 327 case ATT_EVENT_DISCONNECTED: 328 context = connection_for_conn_handle(att_event_disconnected_get_handle(packet)); 329 if (!context) break; 330 // free connection 331 printf("%c: ATT disconnected, handle %04x\n", context->name, context->connection_handle); 332 context->le_notification_enabled = 0; 333 context->connection_handle = HCI_CON_HANDLE_INVALID; 334 break; 335 default: 336 break; 337 } 338 break; 339 default: 340 break; 341 } 342 } 343 /* LISTING_END */ 344 345 /* 346 * @section Streamer 347 * 348 * @text The streamer function checks if notifications are enabled and if a notification can be sent now. 349 * It creates some test data - a single letter that gets increased every time - and tracks the data sent. 350 */ 351 352 /* LISTING_START(streamer): Streaming code */ 353 static void streamer(void){ 354 355 // find next active streaming connection 356 int old_connection_index = connection_index; 357 while (1){ 358 // active found? 359 if ((le_streamer_connections[connection_index].connection_handle != HCI_CON_HANDLE_INVALID) && 360 (le_streamer_connections[connection_index].le_notification_enabled)) break; 361 362 // check next 363 next_connection_index(); 364 365 // none found 366 if (connection_index == old_connection_index) return; 367 } 368 369 le_streamer_connection_t * context = &le_streamer_connections[connection_index]; 370 371 // create test data 372 context->counter++; 373 if (context->counter > 'Z') context->counter = 'A'; 374 memset(context->test_data, context->counter, context->test_data_len); 375 376 // send 377 att_server_notify(context->connection_handle, context->value_handle, (uint8_t*) context->test_data, context->test_data_len); 378 379 // track 380 test_track_sent(context, context->test_data_len); 381 382 // request next send event 383 att_server_request_can_send_now_event(context->connection_handle); 384 385 // check next 386 next_connection_index(); 387 } 388 /* LISTING_END */ 389 390 /* 391 * @section ATT Write 392 * 393 * @text The only valid ATT write in this example is to the Client Characteristic Configuration, which configures notification 394 * and indication. If the ATT handle matches the client configuration handle, the new configuration value is stored. 395 * If notifications get enabled, an ATT_EVENT_CAN_SEND_NOW is requested. See Listing attWrite. 396 */ 397 398 /* LISTING_START(attWrite): ATT Write */ 399 static int att_write_callback(hci_con_handle_t con_handle, uint16_t att_handle, uint16_t transaction_mode, uint16_t offset, uint8_t *buffer, uint16_t buffer_size){ 400 UNUSED(offset); 401 402 // printf("att_write_callback att_handle %04x, transaction mode %u\n", att_handle, transaction_mode); 403 if (transaction_mode != ATT_TRANSACTION_MODE_NONE) return 0; 404 le_streamer_connection_t * context = connection_for_conn_handle(con_handle); 405 switch(att_handle){ 406 case ATT_CHARACTERISTIC_0000FF11_0000_1000_8000_00805F9B34FB_01_CLIENT_CONFIGURATION_HANDLE: 407 case ATT_CHARACTERISTIC_0000FF12_0000_1000_8000_00805F9B34FB_01_CLIENT_CONFIGURATION_HANDLE: 408 context->le_notification_enabled = little_endian_read_16(buffer, 0) == GATT_CLIENT_CHARACTERISTICS_CONFIGURATION_NOTIFICATION; 409 printf("%c: Notifications enabled %u\n", context->name, context->le_notification_enabled); 410 if (context->le_notification_enabled){ 411 switch (att_handle){ 412 case ATT_CHARACTERISTIC_0000FF11_0000_1000_8000_00805F9B34FB_01_CLIENT_CONFIGURATION_HANDLE: 413 context->value_handle = ATT_CHARACTERISTIC_0000FF11_0000_1000_8000_00805F9B34FB_01_VALUE_HANDLE; 414 break; 415 case ATT_CHARACTERISTIC_0000FF12_0000_1000_8000_00805F9B34FB_01_CLIENT_CONFIGURATION_HANDLE: 416 context->value_handle = ATT_CHARACTERISTIC_0000FF12_0000_1000_8000_00805F9B34FB_01_VALUE_HANDLE; 417 break; 418 default: 419 break; 420 } 421 att_server_request_can_send_now_event(context->connection_handle); 422 } 423 test_reset(context); 424 break; 425 case ATT_CHARACTERISTIC_0000FF11_0000_1000_8000_00805F9B34FB_01_VALUE_HANDLE: 426 case ATT_CHARACTERISTIC_0000FF12_0000_1000_8000_00805F9B34FB_01_VALUE_HANDLE: 427 test_track_sent(context, buffer_size); 428 break; 429 default: 430 printf("Write to 0x%04x, len %u\n", att_handle, buffer_size); 431 } 432 return 0; 433 } 434 /* LISTING_END */ 435 436 int btstack_main(void); 437 int btstack_main(void) 438 { 439 le_streamer_setup(); 440 441 // turn on! 442 hci_power_control(HCI_POWER_ON); 443 444 return 0; 445 } 446 /* EXAMPLE_END */ 447