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_counter.c" 39 40 // ***************************************************************************** 41 /* EXAMPLE_START(gatt_counter): GATT Server - Heartbeat Counter over GATT 42 * 43 * @text All newer operating systems provide GATT Client functionality. 44 * The LE Counter examples demonstrates how to specify a minimal GATT Database 45 * with a custom GATT Service and a custom Characteristic that sends periodic 46 * notifications. 47 */ 48 // ***************************************************************************** 49 50 #include <stdint.h> 51 #include <stdio.h> 52 #include <stdlib.h> 53 #include <string.h> 54 55 #include "gatt_counter.h" 56 #include "btstack.h" 57 #include "ble/gatt-service/battery_service_server.h" 58 59 #define HEARTBEAT_PERIOD_MS 1000 60 61 /* @section Main Application Setup 62 * 63 * @text Listing MainConfiguration shows main application code. 64 * It initializes L2CAP, the Security Manager and configures the ATT Server with the pre-compiled 65 * ATT Database generated from $le_counter.gatt$. 66 * Additionally, it enables the Battery Service Server with the current battery level. 67 * Finally, it configures the advertisements 68 * and the heartbeat handler and boots the Bluetooth stack. 69 * In this example, the Advertisement contains the Flags attribute and the device name. 70 * The flag 0x06 indicates: LE General Discoverable Mode and BR/EDR not supported. 71 */ 72 73 /* LISTING_START(MainConfiguration): Init L2CAP SM ATT Server and start heartbeat timer */ 74 static int le_notification_enabled; 75 static btstack_timer_source_t heartbeat; 76 static btstack_packet_callback_registration_t hci_event_callback_registration; 77 static hci_con_handle_t con_handle; 78 static uint8_t battery = 100; 79 80 #ifdef ENABLE_GATT_OVER_CLASSIC 81 static uint8_t gatt_service_buffer[70]; 82 #endif 83 84 static void packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size); 85 static uint16_t att_read_callback(hci_con_handle_t con_handle, uint16_t att_handle, uint16_t offset, uint8_t * buffer, uint16_t buffer_size); 86 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); 87 static void heartbeat_handler(struct btstack_timer_source *ts); 88 static void beat(void); 89 90 // Flags general discoverable, BR/EDR supported (== not supported flag not set) when ENABLE_GATT_OVER_CLASSIC is enabled 91 #ifdef ENABLE_GATT_OVER_CLASSIC 92 #define APP_AD_FLAGS 0x02 93 #else 94 #define APP_AD_FLAGS 0x06 95 #endif 96 97 const uint8_t adv_data[] = { 98 // Flags general discoverable 99 0x02, BLUETOOTH_DATA_TYPE_FLAGS, APP_AD_FLAGS, 100 // Name 101 0x0b, BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME, 'L', 'E', ' ', 'C', 'o', 'u', 'n', 't', 'e', 'r', 102 // Incomplete List of 16-bit Service Class UUIDs -- FF10 - only valid for testing! 103 0x03, BLUETOOTH_DATA_TYPE_INCOMPLETE_LIST_OF_16_BIT_SERVICE_CLASS_UUIDS, 0x10, 0xff, 104 }; 105 const uint8_t adv_data_len = sizeof(adv_data); 106 107 static void le_counter_setup(void){ 108 109 l2cap_init(); 110 111 // setup SM: Display only 112 sm_init(); 113 114 #ifdef ENABLE_GATT_OVER_CLASSIC 115 // init SDP, create record for GATT and register with SDP 116 sdp_init(); 117 memset(gatt_service_buffer, 0, sizeof(gatt_service_buffer)); 118 gatt_create_sdp_record(gatt_service_buffer, sdp_create_service_record_handle(), ATT_SERVICE_GATT_SERVICE_START_HANDLE, ATT_SERVICE_GATT_SERVICE_END_HANDLE); 119 btstack_assert(de_get_len( gatt_service_buffer) <= sizeof(gatt_service_buffer)); 120 sdp_register_service(gatt_service_buffer); 121 122 // configure Classic GAP 123 gap_set_local_name("GATT Counter BR/EDR 00:00:00:00:00:00"); 124 gap_ssp_set_io_capability(SSP_IO_CAPABILITY_DISPLAY_YES_NO); 125 gap_discoverable_control(1); 126 #endif 127 128 // setup ATT server 129 att_server_init(profile_data, att_read_callback, att_write_callback); 130 131 // setup battery service 132 battery_service_server_init(battery); 133 134 // setup advertisements 135 uint16_t adv_int_min = 0x0030; 136 uint16_t adv_int_max = 0x0030; 137 uint8_t adv_type = 0; 138 bd_addr_t null_addr; 139 memset(null_addr, 0, 6); 140 gap_advertisements_set_params(adv_int_min, adv_int_max, adv_type, 0, null_addr, 0x07, 0x00); 141 gap_advertisements_set_data(adv_data_len, (uint8_t*) adv_data); 142 gap_advertisements_enable(1); 143 144 // register for HCI events 145 hci_event_callback_registration.callback = &packet_handler; 146 hci_add_event_handler(&hci_event_callback_registration); 147 148 // register for ATT event 149 att_server_register_packet_handler(packet_handler); 150 151 // set one-shot timer 152 heartbeat.process = &heartbeat_handler; 153 btstack_run_loop_set_timer(&heartbeat, HEARTBEAT_PERIOD_MS); 154 btstack_run_loop_add_timer(&heartbeat); 155 156 // beat once 157 beat(); 158 } 159 /* LISTING_END */ 160 161 /* 162 * @section Heartbeat Handler 163 * 164 * @text The heartbeat handler updates the value of the single Characteristic provided in this example, 165 * and request a ATT_EVENT_CAN_SEND_NOW to send a notification if enabled see Listing heartbeat. 166 */ 167 168 /* LISTING_START(heartbeat): Hearbeat Handler */ 169 static int counter = 0; 170 static char counter_string[30]; 171 static int counter_string_len; 172 173 static void beat(void){ 174 counter++; 175 counter_string_len = snprintf(counter_string, sizeof(counter_string), "BTstack counter %04u", counter); 176 puts(counter_string); 177 } 178 179 static void heartbeat_handler(struct btstack_timer_source *ts){ 180 if (le_notification_enabled) { 181 beat(); 182 att_server_request_can_send_now_event(con_handle); 183 } 184 185 // simulate battery drain 186 battery--; 187 if (battery < 50) { 188 battery = 100; 189 } 190 battery_service_server_set_battery_value(battery); 191 192 btstack_run_loop_set_timer(ts, HEARTBEAT_PERIOD_MS); 193 btstack_run_loop_add_timer(ts); 194 } 195 /* LISTING_END */ 196 197 /* 198 * @section Packet Handler 199 * 200 * @text The packet handler is used to: 201 * - stop the counter after a disconnect 202 * - send a notification when the requested ATT_EVENT_CAN_SEND_NOW is received 203 */ 204 205 /* LISTING_START(packetHandler): Packet Handler */ 206 static void packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 207 UNUSED(channel); 208 UNUSED(size); 209 210 if (packet_type != HCI_EVENT_PACKET) return; 211 212 switch (hci_event_packet_get_type(packet)) { 213 case HCI_EVENT_DISCONNECTION_COMPLETE: 214 le_notification_enabled = 0; 215 break; 216 case ATT_EVENT_CAN_SEND_NOW: 217 att_server_notify(con_handle, ATT_CHARACTERISTIC_0000FF11_0000_1000_8000_00805F9B34FB_01_VALUE_HANDLE, (uint8_t*) counter_string, counter_string_len); 218 break; 219 default: 220 break; 221 } 222 } 223 224 /* LISTING_END */ 225 226 /* 227 * @section ATT Read 228 * 229 * @text The ATT Server handles all reads to constant data. For dynamic data like the custom characteristic, the registered 230 * att_read_callback is called. To handle long characteristics and long reads, the att_read_callback is first called 231 * with buffer == NULL, to request the total value length. Then it will be called again requesting a chunk of the value. 232 * See Listing attRead. 233 */ 234 235 /* LISTING_START(attRead): ATT Read */ 236 237 // ATT Client Read Callback for Dynamic Data 238 // - if buffer == NULL, don't copy data, just return size of value 239 // - if buffer != NULL, copy data and return number bytes copied 240 // @param offset defines start of attribute value 241 static uint16_t att_read_callback(hci_con_handle_t connection_handle, uint16_t att_handle, uint16_t offset, uint8_t * buffer, uint16_t buffer_size){ 242 UNUSED(connection_handle); 243 244 if (att_handle == ATT_CHARACTERISTIC_0000FF11_0000_1000_8000_00805F9B34FB_01_VALUE_HANDLE){ 245 return att_read_callback_handle_blob((const uint8_t *)counter_string, counter_string_len, offset, buffer, buffer_size); 246 } 247 return 0; 248 } 249 /* LISTING_END */ 250 251 252 /* 253 * @section ATT Write 254 * 255 * @text The only valid ATT writes in this example are to the Client Characteristic Configuration, which configures notification 256 * and indication and to the the Characteristic Value. 257 * If the ATT handle matches the client configuration handle, the new configuration value is stored and used 258 * in the heartbeat handler to decide if a new value should be sent. 259 * If the ATT handle matches the characteristic value handle, we print the write as hexdump 260 * See Listing attWrite. 261 */ 262 263 /* LISTING_START(attWrite): ATT Write */ 264 static int att_write_callback(hci_con_handle_t connection_handle, uint16_t att_handle, uint16_t transaction_mode, uint16_t offset, uint8_t *buffer, uint16_t buffer_size){ 265 switch (att_handle){ 266 case ATT_CHARACTERISTIC_0000FF11_0000_1000_8000_00805F9B34FB_01_CLIENT_CONFIGURATION_HANDLE: 267 le_notification_enabled = little_endian_read_16(buffer, 0) == GATT_CLIENT_CHARACTERISTICS_CONFIGURATION_NOTIFICATION; 268 con_handle = connection_handle; 269 break; 270 case ATT_CHARACTERISTIC_0000FF11_0000_1000_8000_00805F9B34FB_01_VALUE_HANDLE: 271 printf("Write: transaction mode %u, offset %u, data (%u bytes): ", transaction_mode, offset, buffer_size); 272 printf_hexdump(buffer, buffer_size); 273 break; 274 default: 275 break; 276 } 277 return 0; 278 } 279 /* LISTING_END */ 280 281 int btstack_main(void); 282 int btstack_main(void) 283 { 284 le_counter_setup(); 285 286 // turn on! 287 hci_power_control(HCI_POWER_ON); 288 289 return 0; 290 } 291 /* EXAMPLE_END */ 292