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
le_counter_setup(void)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
beat(void)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
heartbeat_handler(struct btstack_timer_source * ts)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 */
packet_handler(uint8_t packet_type,uint16_t channel,uint8_t * packet,uint16_t size)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
att_read_callback(hci_con_handle_t connection_handle,uint16_t att_handle,uint16_t offset,uint8_t * buffer,uint16_t buffer_size)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 */
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)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);
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