xref: /btstack/src/ble/gatt-service/cycling_power_service_server.c (revision d58a1b5f11ada8ddf896c41fff5a35e7f140c37e)
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 MATTHIAS
24  * RINGWALD 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__ "cycling_power_service_server.c"
39 
40 
41 #include "bluetooth.h"
42 #include "btstack_defines.h"
43 #include "bluetooth_data_types.h"
44 #include "btstack_event.h"
45 #include "ble/att_db.h"
46 #include "ble/att_server.h"
47 #include "btstack_util.h"
48 #include "bluetooth_gatt.h"
49 #include "btstack_debug.h"
50 #include "l2cap.h"
51 #include "hci.h"
52 
53 #include "ble/gatt-service/cycling_power_service_server.h"
54 
55 #define CYCLING_POWER_MAX_BROACAST_MSG_SIZE         31
56 #define CONTROL_POINT_PROCEDURE_TIMEOUT_MS          30
57 #define CYCLING_POWER_MEASUREMENT_FLAGS_CLEARED     0xFFFF
58 
59 typedef enum {
60     CP_MASK_BIT_PEDAL_POWER_BALANCE = 0,
61     CP_MASK_BIT_ACCUMULATED_TORQUE,
62     CP_MASK_BIT_WHEEL_REVOLUTION_DATA,
63     CP_MASK_BIT_CRANK_REVOLUTION_DATA,
64     CP_MASK_BIT_EXTREME_MAGNITUDES,
65     CP_MASK_BIT_EXTREME_ANGLES,
66     CP_MASK_BIT_TOP_DEAD_SPOT_ANGLE,
67     CP_MASK_BIT_BOTTOM_DEAD_SPOT_ANGLE,
68     CP_MASK_BIT_ACCUMULATED_ENERGY,
69     CP_MASK_BIT_RESERVED
70 } cycling_power_mask_bit_t;
71 
72 typedef enum {
73     CP_OPCODE_IDLE = 0,
74     CP_OPCODE_SET_CUMULATIVE_VALUE,
75     CP_OPCODE_UPDATE_SENSOR_LOCATION,
76     CP_OPCODE_REQUEST_SUPPORTED_SENSOR_LOCATIONS,
77     CP_OPCODE_SET_CRANK_LENGTH,
78     CP_OPCODE_REQUEST_CRANK_LENGTH,
79     CP_OPCODE_SET_CHAIN_LENGTH,
80     CP_OPCODE_REQUEST_CHAIN_LENGTH,
81     CP_OPCODE_SET_CHAIN_WEIGHT,
82     CP_OPCODE_REQUEST_CHAIN_WEIGHT,
83     CP_OPCODE_SET_SPAN_LENGTH,
84     CP_OPCODE_REQUEST_SPAN_LENGTH,
85     CP_OPCODE_START_OFFSET_COMPENSATION,
86     CP_OPCODE_MASK_CYCLING_POWER_MEASUREMENT_CHARACTERISTIC_CONTENT,
87     CP_OPCODE_REQUEST_SAMPLING_RATE,
88     CP_OPCODE_REQUEST_FACTORY_CALIBRATION_DATE,
89     CP_OPCODE_START_ENHANCED_OFFSET_COMPENSATION,
90     CP_OPCODE_RESPONSE_CODE = 32
91 } cycling_power_opcode_t;
92 
93 typedef enum {
94     CP_RESPONSE_VALUE_SUCCESS = 1,
95     CP_RESPONSE_VALUE_OP_CODE_NOT_SUPPORTED,
96     CP_RESPONSE_VALUE_INVALID_PARAMETER,
97     CP_RESPONSE_VALUE_OPERATION_FAILED,
98     CP_RESPONSE_VALUE_NOT_AVAILABLE,
99     CP_RESPONSE_VALUE_W4_VALUE_AVAILABLE
100 } cycling_power_response_value_t;
101 
102 typedef enum {
103     CP_CONNECTION_INTERVAL_STATUS_NONE = 0,
104     CP_CONNECTION_INTERVAL_STATUS_RECEIVED,
105     CP_CONNECTION_INTERVAL_STATUS_ACCEPTED,
106     CP_CONNECTION_INTERVAL_STATUS_W4_L2CAP_RESPONSE,
107     CP_CONNECTION_INTERVAL_STATUS_W4_UPDATE,
108     CP_CONNECTION_INTERVAL_STATUS_REJECTED
109 } cycling_power_con_interval_status_t;
110 
111 typedef struct {
112     hci_con_handle_t con_handle;
113     // GATT connection management
114     uint16_t con_interval;
115     uint16_t con_interval_min;
116     uint16_t con_interval_max;
117     cycling_power_con_interval_status_t  con_interval_status;
118 
119     // Cycling Power Measurement
120     uint16_t measurement_value_handle;
121     int16_t  instantaneous_power_watt;
122 
123     cycling_power_pedal_power_balance_reference_t  pedal_power_balance_reference;
124     uint8_t  pedal_power_balance_percentage;    // percentage, resolution 1/2,
125                                                 // If the sensor provides the power balance referenced to the left pedal,
126                                                 // the power balance is calculated as [LeftPower/(LeftPower + RightPower)]*100 in units of percent
127 
128     cycling_power_torque_source_t torque_source;
129     uint16_t accumulated_torque_m;              // meters, resolution 1/32,
130                                                 // The Accumulated Torque value may decrease
131     // wheel revolution data:
132     uint32_t cumulative_wheel_revolutions;      // CANNOT roll over
133     uint16_t last_wheel_event_time_s;           // seconds, resolution 1/2048
134     // crank revolution data:
135     uint16_t cumulative_crank_revolutions;
136     uint16_t last_crank_event_time_s;           // seconds, resolution 1/1024
137     // extreme force magnitudes
138     int16_t  maximum_force_magnitude_newton;
139     int16_t  minimum_force_magnitude_newton;
140     int16_t  maximum_torque_magnitude_newton_m;     // newton meters, resolution 1/32
141     int16_t  minimum_torque_magnitude_newton_m;     // newton meters, resolution 1/32
142     // extreme angles
143     uint16_t maximum_angle_deg;                 // 12bit, degrees
144     uint16_t minimum_angle_deg;                 // 12bit, degrees, concatenated with previous into 3 octets
145                                                 // i.e. if the Maximum Angle is 0xABC and the Minimum Angle is 0x123, the transmitted value is 0x123ABC.
146     uint16_t top_dead_spot_angle_deg;
147     uint16_t bottom_dead_spot_angle_deg;            // The Bottom Dead Spot Angle field represents the crank angle when the value of the Instantaneous Power value becomes negative.
148     uint16_t accumulated_energy_kJ;             // kilojoules; CANNOT roll over
149 
150     // uint8_t  offset_compensation;
151 
152     // CP Measurement Notification (Client Characteristic Configuration)
153     uint16_t measurement_client_configuration_descriptor_handle;
154     uint16_t measurement_client_configuration_descriptor_notify;
155     btstack_context_callback_registration_t measurement_notify_callback;
156 
157     // CP Measurement Broadcast (Server Characteristic Configuration)
158     uint16_t measurement_server_configuration_descriptor_handle;
159     uint16_t measurement_server_configuration_descriptor_broadcast;
160     btstack_context_callback_registration_t measurement_broadcast_callback;
161 
162     // Cycling Power Feature
163     uint16_t feature_value_handle;
164     uint32_t feature_flags;                             // see cycling_power_feature_flag_t
165     uint16_t masked_measurement_flags;
166     uint16_t default_measurement_flags;
167 
168     // Sensor Location
169     uint16_t sensor_location_value_handle;
170     cycling_power_sensor_location_t sensor_location;    // see cycling_power_sensor_location_t
171     cycling_power_sensor_location_t * supported_sensor_locations;
172     uint16_t num_supported_sensor_locations;
173     uint16_t crank_length_mm;                           // resolution 1/2 mm
174     uint16_t chain_length_mm;                           // resolution 1 mm
175     uint16_t chain_weight_g;                            // resolution 1 gram
176     uint16_t span_length_mm;                            // resolution 1 mm
177 
178     gatt_date_time_t factory_calibration_date;
179 
180     uint8_t  sampling_rate_hz;                          // resolution 1 Herz
181 
182     int16_t  current_force_magnitude_newton;
183     int16_t  current_torque_magnitude_newton_m;     // newton meters, resolution 1/32
184     uint16_t manufacturer_company_id;
185     uint8_t num_manufacturer_specific_data;
186     uint8_t * manufacturer_specific_data;
187 
188     // Cycling Power Vector
189     uint16_t vector_value_handle;
190     uint16_t vector_cumulative_crank_revolutions;
191     uint16_t vector_last_crank_event_time_s;                            // seconds, resolution 1/1024
192     uint16_t vector_first_crank_measurement_angle_deg;
193     int16_t  * vector_instantaneous_force_magnitude_newton_array;           // newton
194     int force_magnitude_count;
195     int16_t  * vector_instantaneous_torque_magnitude_newton_per_m_array;    // newton per meter, resolution 1/32
196     int torque_magnitude_count;
197     cycling_power_instantaneous_measurement_direction_t vector_instantaneous_measurement_direction;
198 
199     // CP Vector Notification (Client Characteristic Configuration)
200     uint16_t vector_client_configuration_descriptor_handle;
201     uint16_t vector_client_configuration_descriptor_notify;
202     btstack_context_callback_registration_t vector_notify_callback;
203 
204     // CP Control Point
205     uint16_t control_point_value_handle;
206     // CP Control Point Indication (Client Characteristic Configuration)
207     uint16_t control_point_client_configuration_descriptor_handle;
208     uint16_t control_point_client_configuration_descriptor_indicate;
209     btstack_context_callback_registration_t control_point_indicate_callback;
210 
211     cycling_power_opcode_t request_opcode;
212     cycling_power_response_value_t response_value;
213 
214     btstack_packet_handler_t calibration_callback;
215     uint8_t w4_indication_complete;
216 } cycling_power_t;
217 
218 static att_service_handler_t cycling_power_service;
219 static cycling_power_t cycling_power;
220 static btstack_packet_callback_registration_t hci_event_callback_registration;
221 
222 static uint16_t cycling_power_service_read_callback(hci_con_handle_t con_handle, uint16_t attribute_handle, uint16_t offset, uint8_t * buffer, uint16_t buffer_size){
223     UNUSED(con_handle);
224     UNUSED(attribute_handle);
225     UNUSED(offset);
226     cycling_power_t * instance = &cycling_power;
227 
228     if (attribute_handle == instance->measurement_client_configuration_descriptor_handle){
229         if (buffer && (buffer_size >= 2)){
230             little_endian_store_16(buffer, 0, instance->measurement_client_configuration_descriptor_notify);
231         }
232         return 2;
233     }
234 
235     if (attribute_handle == instance->measurement_server_configuration_descriptor_handle){
236         if (buffer && (buffer_size >= 2)){
237             little_endian_store_16(buffer, 0, instance->measurement_server_configuration_descriptor_broadcast);
238         }
239         return 2;
240     }
241 
242     if (attribute_handle == instance->vector_client_configuration_descriptor_handle){
243         if (buffer && (buffer_size >= 2)){
244             little_endian_store_16(buffer, 0, instance->vector_client_configuration_descriptor_notify);
245         }
246         return 2;
247     }
248 
249     if (attribute_handle == instance->control_point_client_configuration_descriptor_handle){
250         if (buffer && (buffer_size >= 2)){
251             little_endian_store_16(buffer, 0, instance->control_point_client_configuration_descriptor_indicate);
252         }
253         return 2;
254     }
255 
256     if (attribute_handle == instance->feature_value_handle){
257         if (buffer && (buffer_size >= 4)){
258             little_endian_store_32(buffer, 0, instance->feature_flags);
259         }
260         return 4;
261     }
262 
263     if (attribute_handle == instance->sensor_location_value_handle){
264         if (buffer && (buffer_size >= 1)){
265             buffer[0] = instance->sensor_location;
266         }
267         return 1;
268     }
269     return 0;
270 }
271 
272 static int has_feature(cycling_power_feature_flag_t feature){
273     cycling_power_t * instance = &cycling_power;
274     return (instance->feature_flags & (1 << feature)) != 0;
275 }
276 
277 static int cycling_power_vector_instantaneous_measurement_direction(void){
278     cycling_power_t * instance = &cycling_power;
279     return instance->vector_instantaneous_measurement_direction;
280 }
281 
282 static uint16_t cycling_power_service_default_measurement_flags(void){
283     cycling_power_t * instance = &cycling_power;
284     uint16_t measurement_flags = 0;
285     uint8_t flag[] = {
286         (uint8_t) has_feature(CP_FEATURE_FLAG_PEDAL_POWER_BALANCE_SUPPORTED),
287         (uint8_t) has_feature(CP_FEATURE_FLAG_PEDAL_POWER_BALANCE_SUPPORTED) && instance->pedal_power_balance_reference,
288         (uint8_t) has_feature(CP_FEATURE_FLAG_ACCUMULATED_TORQUE_SUPPORTED),
289         (uint8_t) has_feature(CP_FEATURE_FLAG_ACCUMULATED_TORQUE_SUPPORTED) && instance->torque_source,
290         (uint8_t) has_feature(CP_FEATURE_FLAG_WHEEL_REVOLUTION_DATA_SUPPORTED),
291         (uint8_t) has_feature(CP_FEATURE_FLAG_CRANK_REVOLUTION_DATA_SUPPORTED),
292         (uint8_t) has_feature(CP_FEATURE_FLAG_EXTREME_MAGNITUDES_SUPPORTED) && (has_feature(CP_FEATURE_FLAG_SENSOR_MEASUREMENT_CONTEXT) == CP_SENSOR_MEASUREMENT_CONTEXT_FORCE),
293         (uint8_t) has_feature(CP_FEATURE_FLAG_EXTREME_MAGNITUDES_SUPPORTED) && (has_feature(CP_FEATURE_FLAG_SENSOR_MEASUREMENT_CONTEXT) == CP_SENSOR_MEASUREMENT_CONTEXT_TORQUE),
294         (uint8_t) has_feature(CP_FEATURE_FLAG_EXTREME_ANGLES_SUPPORTED),
295         (uint8_t) has_feature(CP_FEATURE_FLAG_TOP_AND_BOTTOM_DEAD_SPOT_ANGLE_SUPPORTED),
296         (uint8_t) has_feature(CP_FEATURE_FLAG_TOP_AND_BOTTOM_DEAD_SPOT_ANGLE_SUPPORTED),
297         (uint8_t) has_feature(CP_FEATURE_FLAG_ACCUMULATED_ENERGY_SUPPORTED),
298         (uint8_t) has_feature(CP_FEATURE_FLAG_OFFSET_COMPENSATION_INDICATOR_SUPPORTED)
299     };
300 
301     int i;
302     for (i = CP_MEASUREMENT_FLAG_PEDAL_POWER_BALANCE_PRESENT; i <= CP_MEASUREMENT_FLAG_OFFSET_COMPENSATION_INDICATOR; i++){
303         measurement_flags |= flag[i] << i;
304     }
305 
306     return measurement_flags;
307 }
308 
309 static uint16_t cycling_power_service_get_measurement_flags(cycling_power_t * instance){
310     if (!instance) return 0;
311     if (instance->masked_measurement_flags != CYCLING_POWER_MEASUREMENT_FLAGS_CLEARED){
312         return instance->masked_measurement_flags;
313     }
314     if (instance->default_measurement_flags == CYCLING_POWER_MEASUREMENT_FLAGS_CLEARED){
315         instance->default_measurement_flags = cycling_power_service_default_measurement_flags();
316     }
317     return instance->default_measurement_flags;
318 }
319 
320 
321 uint16_t cycling_power_service_measurement_flags(void){
322     cycling_power_t * instance = &cycling_power;
323     return cycling_power_service_get_measurement_flags(instance);
324 }
325 
326 uint8_t cycling_power_service_vector_flags(void){
327     uint8_t vector_flags = 0;
328     uint8_t flag[] = {
329         (uint8_t )has_feature(CP_FEATURE_FLAG_CRANK_REVOLUTION_DATA_SUPPORTED),
330         (uint8_t )has_feature(CP_FEATURE_FLAG_EXTREME_ANGLES_SUPPORTED),
331         (uint8_t )has_feature(CP_FEATURE_FLAG_EXTREME_MAGNITUDES_SUPPORTED) && (has_feature(CP_FEATURE_FLAG_SENSOR_MEASUREMENT_CONTEXT) == CP_SENSOR_MEASUREMENT_CONTEXT_FORCE),
332         (uint8_t )has_feature(CP_FEATURE_FLAG_EXTREME_MAGNITUDES_SUPPORTED) && (has_feature(CP_FEATURE_FLAG_SENSOR_MEASUREMENT_CONTEXT) == CP_SENSOR_MEASUREMENT_CONTEXT_TORQUE),
333         (uint8_t )has_feature(CP_FEATURE_FLAG_INSTANTANEOUS_MEASUREMENT_DIRECTION_SUPPORTED) && cycling_power_vector_instantaneous_measurement_direction()
334     };
335 
336     int i;
337     for (i = CP_VECTOR_FLAG_CRANK_REVOLUTION_DATA_PRESENT; i <= CP_VECTOR_FLAG_INSTANTANEOUS_MEASUREMENT_DIRECTION; i++){
338         vector_flags |= flag[i] << i;
339     }
340     return vector_flags;
341 }
342 
343 static void cycling_power_service_vector_can_send_now(void * context){
344     cycling_power_t * instance = (cycling_power_t *) context;
345     if (!instance){
346         log_error("cycling_power_service_measurement_can_send_now: instance is null");
347         return;
348     }
349     uint8_t value[50];
350     uint8_t vector_flags = cycling_power_service_vector_flags();
351     int pos = 0;
352 
353     value[pos++] = vector_flags;
354     int i;
355     for (i = CP_VECTOR_FLAG_CRANK_REVOLUTION_DATA_PRESENT; i <= CP_VECTOR_FLAG_INSTANTANEOUS_MEASUREMENT_DIRECTION; i++){
356         if ((vector_flags & (1 << i)) == 0) continue;
357         switch ((cycling_power_vector_flag_t) i){
358             case CP_VECTOR_FLAG_CRANK_REVOLUTION_DATA_PRESENT:
359                 little_endian_store_16(value, pos, instance->cumulative_crank_revolutions);
360                 pos += 2;
361                 little_endian_store_16(value, pos, instance->last_crank_event_time_s);
362                 pos += 2;
363                 break;
364             case CP_VECTOR_FLAG_INSTANTANEOUS_FORCE_MAGNITUDE_ARRAY_PRESENT:{
365                 uint16_t att_mtu = att_server_get_mtu(instance->con_handle);
366                 uint16_t bytes_left = 0;
367                 if (att_mtu > (pos + 3)){
368                     bytes_left = btstack_min(sizeof(value), att_mtu - 3 - pos);
369                 }
370                 while ((bytes_left > 2) && instance->force_magnitude_count){
371                     little_endian_store_16(value, pos, instance->vector_instantaneous_force_magnitude_newton_array[0]);
372                     pos += 2;
373                     bytes_left -= 2;
374                     instance->vector_instantaneous_force_magnitude_newton_array++;
375                     instance->force_magnitude_count--;
376                 }
377                 break;
378             }
379             case CP_VECTOR_FLAG_INSTANTANEOUS_TORQUE_MAGNITUDE_ARRAY_PRESENT:{
380                 uint16_t att_mtu = att_server_get_mtu(instance->con_handle);
381                 uint16_t bytes_left = 0;
382                 if (att_mtu > (pos + 3)){
383                     bytes_left = btstack_min(sizeof(value), att_mtu - 3 - pos);
384                 }
385 
386                 while ((bytes_left > 2) && instance->torque_magnitude_count){
387                     little_endian_store_16(value, pos, instance->vector_instantaneous_torque_magnitude_newton_per_m_array[0]);
388                     pos += 2;
389                     bytes_left -= 2;
390                     instance->vector_instantaneous_torque_magnitude_newton_per_m_array++;
391                     instance->torque_magnitude_count--;
392                 }
393                 break;
394             }
395             case CP_VECTOR_FLAG_FIRST_CRANK_MEASUREMENT_ANGLE_PRESENT:
396                 // printf("CP_VECTOR_FLAG_FIRST_CRANK_MEASUREMENT_ANGLE_PRESENT \n");
397                 little_endian_store_16(value, pos, instance->vector_first_crank_measurement_angle_deg);
398                 pos += 2;
399                 break;
400             case CP_VECTOR_FLAG_INSTANTANEOUS_MEASUREMENT_DIRECTION:
401                 break;
402             default:
403                 break;
404         }
405     }
406 
407     att_server_notify(instance->con_handle, instance->vector_value_handle, &value[0], pos);
408 }
409 
410 static int cycling_power_measurement_flag_value_size(cycling_power_measurement_flag_t flag){
411     switch (flag){
412         case CP_MEASUREMENT_FLAG_PEDAL_POWER_BALANCE_PRESENT:
413             return 1;
414         case CP_MEASUREMENT_FLAG_WHEEL_REVOLUTION_DATA_PRESENT:
415             return 6;
416         case CP_MEASUREMENT_FLAG_CRANK_REVOLUTION_DATA_PRESENT:
417         case CP_MEASUREMENT_FLAG_EXTREME_FORCE_MAGNITUDES_PRESENT:
418         case CP_MEASUREMENT_FLAG_EXTREME_TORQUE_MAGNITUDES_PRESENT:
419             return 4;
420         case CP_MEASUREMENT_FLAG_EXTREME_ANGLES_PRESENT:
421             return 3;
422         case CP_MEASUREMENT_FLAG_ACCUMULATED_TORQUE_PRESENT:
423         case CP_MEASUREMENT_FLAG_TOP_DEAD_SPOT_ANGLE_PRESENT:
424         case CP_MEASUREMENT_FLAG_BOTTOM_DEAD_SPOT_ANGLE_PRESENT:
425         case CP_MEASUREMENT_FLAG_ACCUMULATED_ENERGY_PRESENT:
426             return 2;
427         default:
428             return 0;
429     }
430 }
431 
432 static int cycling_power_store_measurement_flag_value(cycling_power_t * instance, cycling_power_measurement_flag_t flag, uint8_t * value){
433     if (!instance) return 0;
434 
435     int pos = 0;
436     switch (flag){
437         case CP_MEASUREMENT_FLAG_PEDAL_POWER_BALANCE_PRESENT:
438             value[pos++] = instance->pedal_power_balance_percentage;
439             break;
440         case CP_MEASUREMENT_FLAG_ACCUMULATED_TORQUE_PRESENT:
441             little_endian_store_16(value, pos, instance->accumulated_torque_m);
442             pos += 2;
443             break;
444         case CP_MEASUREMENT_FLAG_WHEEL_REVOLUTION_DATA_PRESENT:
445             little_endian_store_32(value, pos, instance->cumulative_wheel_revolutions);
446             pos += 4;
447             little_endian_store_16(value, pos, instance->last_wheel_event_time_s);
448             pos += 2;
449             break;
450         case CP_MEASUREMENT_FLAG_CRANK_REVOLUTION_DATA_PRESENT:
451             little_endian_store_16(value, pos, instance->cumulative_crank_revolutions);
452             pos += 2;
453             little_endian_store_16(value, pos, instance->last_crank_event_time_s);
454             pos += 2;
455             break;
456         case CP_MEASUREMENT_FLAG_EXTREME_FORCE_MAGNITUDES_PRESENT:
457             little_endian_store_16(value, pos, (uint16_t)instance->maximum_force_magnitude_newton);
458             pos += 2;
459             little_endian_store_16(value, pos, (uint16_t)instance->minimum_force_magnitude_newton);
460             pos += 2;
461             break;
462         case CP_MEASUREMENT_FLAG_EXTREME_TORQUE_MAGNITUDES_PRESENT:
463             little_endian_store_16(value, pos, (uint16_t)instance->maximum_torque_magnitude_newton_m);
464             pos += 2;
465             little_endian_store_16(value, pos, (uint16_t)instance->minimum_torque_magnitude_newton_m);
466             pos += 2;
467             break;
468         case CP_MEASUREMENT_FLAG_EXTREME_ANGLES_PRESENT:
469             little_endian_store_24(value, pos, (instance->maximum_angle_deg << 12) | instance->minimum_angle_deg);
470             pos += 3;
471             break;
472         case CP_MEASUREMENT_FLAG_TOP_DEAD_SPOT_ANGLE_PRESENT:
473             little_endian_store_16(value, pos, (uint16_t)instance->top_dead_spot_angle_deg);
474             pos += 2;
475             break;
476         case CP_MEASUREMENT_FLAG_BOTTOM_DEAD_SPOT_ANGLE_PRESENT:
477             little_endian_store_16(value, pos, (uint16_t)instance->bottom_dead_spot_angle_deg);
478             pos += 2;
479             break;
480         case CP_MEASUREMENT_FLAG_ACCUMULATED_ENERGY_PRESENT:
481             little_endian_store_16(value, pos, (uint16_t)instance->accumulated_energy_kJ);
482             pos += 2;
483             break;
484         default:
485             break;
486     }
487     return pos;
488 }
489 
490 
491 static int cycling_power_store_measurement(cycling_power_t * instance, uint8_t * value, uint16_t max_value_size){
492     if (max_value_size < 4) return 0;
493     if (!instance) return 0;
494 
495     uint16_t measurement_flags = cycling_power_service_get_measurement_flags(instance);
496     int pos = 0;
497     little_endian_store_16(value, 0, measurement_flags);
498     pos += 2;
499     little_endian_store_16(value, 2, instance->instantaneous_power_watt);
500     pos += 2;
501     int flag_index;
502     uint16_t bytes_left = max_value_size - pos;
503     for (flag_index = 0; flag_index < CP_MEASUREMENT_FLAG_RESERVED; flag_index++){
504         if ((measurement_flags & (1 << flag_index)) == 0) continue;
505         cycling_power_measurement_flag_t flag = (cycling_power_measurement_flag_t) flag_index;
506         uint16_t value_size = cycling_power_measurement_flag_value_size(flag);
507         if (value_size > bytes_left ) return pos;
508         cycling_power_store_measurement_flag_value(instance, flag, &value[pos]);
509         pos += value_size;
510         bytes_left -= value_size;
511     }
512     return pos;
513 }
514 
515 int cycling_power_get_measurement_adv(uint16_t adv_interval, uint8_t * broadcast_adv, uint16_t max_value_size){
516     if (max_value_size < 12) return 0;
517     cycling_power_t * instance =  &cycling_power;
518     int pos = 0;
519     // adv flags
520     broadcast_adv[pos++] = 2;
521     broadcast_adv[pos++] = BLUETOOTH_DATA_TYPE_FLAGS;
522     broadcast_adv[pos++] = 0x4;
523 
524     // adv interval
525     broadcast_adv[pos++] = 3;
526     broadcast_adv[pos++] = BLUETOOTH_DATA_TYPE_ADVERTISING_INTERVAL;
527     little_endian_store_16(broadcast_adv, pos, adv_interval);
528     pos += 2;
529     //
530     int value_len = cycling_power_store_measurement(instance, &broadcast_adv[pos+4], CYCLING_POWER_MAX_BROACAST_MSG_SIZE - (pos + 4));
531     broadcast_adv[pos++] = 3 + value_len;
532     broadcast_adv[pos++] = BLUETOOTH_DATA_TYPE_SERVICE_DATA_16_BIT_UUID;
533     little_endian_store_16(broadcast_adv, pos, ORG_BLUETOOTH_SERVICE_CYCLING_POWER);
534     pos += 2;
535     // value data already in place cycling_power_get_measurement
536     pos += value_len;
537     // set ADV_NONCONN_IND
538     return pos;
539 }
540 
541 static void cycling_power_service_broadcast_can_send_now(void * context){
542     cycling_power_t * instance = (cycling_power_t *) context;
543     if (!instance){
544         log_error("cycling_power_service_broadcast_can_send_now: instance is null");
545         return;
546     }
547     uint8_t value[CYCLING_POWER_MAX_BROACAST_MSG_SIZE];
548     int pos = cycling_power_store_measurement(instance, &value[0], sizeof(value));
549     att_server_notify(instance->con_handle, instance->measurement_value_handle, &value[0], pos);
550 }
551 
552 static void cycling_power_service_measurement_can_send_now(void * context){
553     cycling_power_t * instance = (cycling_power_t *) context;
554     if (!instance){
555         log_error("cycling_power_service_measurement_can_send_now: instance is null");
556         return;
557     }
558     uint8_t value[40];
559     int pos = cycling_power_store_measurement(instance, &value[0], sizeof(value));
560     att_server_notify(instance->con_handle, instance->measurement_value_handle, &value[0], pos);
561 }
562 
563 static void cycling_power_service_response_can_send_now(void * context){
564     cycling_power_t * instance = (cycling_power_t *) context;
565     if (!instance){
566         log_error("cycling_power_service_response_can_send_now: instance is null");
567         return;
568     }
569 
570     if (instance->response_value == CP_RESPONSE_VALUE_W4_VALUE_AVAILABLE){
571         log_error("cycling_power_service_response_can_send_now: CP_RESPONSE_VALUE_W4_VALUE_AVAILABLE");
572         return;
573     }
574 
575     // if (instance->w4_indication_complete){
576     //     printf("cycling_power_service_response_can_send_now: w4_indication_complete\n");
577     //     return;
578     // }
579 
580     // use preprocessor instead of btstack_max to get compile-time constant
581 #if (CP_SENSOR_LOCATION_RESERVED > (CYCLING_POWER_MANUFACTURER_SPECIFIC_DATA_MAX_SIZE + 5))
582     #define MAX_RESPONSE_PAYLOAD CP_SENSOR_LOCATION_RESERVED
583 #else
584     #define MAX_RESPONSE_PAYLOAD (CYCLING_POWER_MANUFACTURER_SPECIFIC_DATA_MAX_SIZE + 5)
585 #endif
586 
587     uint8_t value[3 + MAX_RESPONSE_PAYLOAD];
588     int pos = 0;
589     value[pos++] = CP_OPCODE_RESPONSE_CODE;
590     value[pos++] = instance->request_opcode;
591     value[pos++] = instance->response_value;
592     if (instance->response_value == CP_RESPONSE_VALUE_SUCCESS){
593         switch (instance->request_opcode){
594             case CP_OPCODE_REQUEST_SUPPORTED_SENSOR_LOCATIONS:{
595                 int i;
596                 for (i=0; i<instance->num_supported_sensor_locations; i++){
597                     value[pos++] = instance->supported_sensor_locations[i];
598                 }
599                 break;
600             }
601             case CP_OPCODE_REQUEST_CRANK_LENGTH:
602                 little_endian_store_16(value, pos, instance->crank_length_mm);
603                 pos += 2;
604                 break;
605             case CP_OPCODE_REQUEST_CHAIN_LENGTH:
606                 little_endian_store_16(value, pos, instance->chain_length_mm);
607                 pos += 2;
608                 break;
609             case CP_OPCODE_REQUEST_CHAIN_WEIGHT:
610                 little_endian_store_16(value, pos, instance->chain_weight_g);
611                 pos += 2;
612                 break;
613             case CP_OPCODE_REQUEST_SPAN_LENGTH:
614                 little_endian_store_16(value, pos, instance->span_length_mm);
615                 pos += 2;
616                 break;
617             case CP_OPCODE_REQUEST_FACTORY_CALIBRATION_DATE:
618                 little_endian_store_16(value, pos, instance->factory_calibration_date.year);
619                 pos += 2;
620                 value[pos++] = instance->factory_calibration_date.month;
621                 value[pos++] = instance->factory_calibration_date.day;
622                 value[pos++] = instance->factory_calibration_date.hours;
623                 value[pos++] = instance->factory_calibration_date.minutes;
624                 value[pos++] = instance->factory_calibration_date.seconds;
625                 break;
626             case CP_OPCODE_REQUEST_SAMPLING_RATE:
627                 value[pos++] = instance->sampling_rate_hz;
628                 break;
629             case CP_OPCODE_START_OFFSET_COMPENSATION:
630             case CP_OPCODE_START_ENHANCED_OFFSET_COMPENSATION:{
631                 uint16_t calibrated_value = 0xffff;
632                 if (has_feature(CP_FEATURE_FLAG_EXTREME_MAGNITUDES_SUPPORTED)){
633                     if (has_feature(CP_FEATURE_FLAG_SENSOR_MEASUREMENT_CONTEXT) == CP_SENSOR_MEASUREMENT_CONTEXT_FORCE) {
634                         calibrated_value = instance->current_force_magnitude_newton;
635                     } else if (has_feature(CP_FEATURE_FLAG_SENSOR_MEASUREMENT_CONTEXT) == CP_SENSOR_MEASUREMENT_CONTEXT_TORQUE){
636                         calibrated_value = instance->current_torque_magnitude_newton_m;
637                     }
638                 }
639 
640                 if (calibrated_value == CP_CALIBRATION_STATUS_INCORRECT_CALIBRATION_POSITION){
641                      value[pos++] = calibrated_value;
642                      // do not include manufacturer ID and data
643                      break;
644                 } else if (calibrated_value == CP_CALIBRATION_STATUS_MANUFACTURER_SPECIFIC_ERROR_FOLLOWS){
645                     value[pos++] = calibrated_value;
646                 } else {
647                     little_endian_store_16(value, pos, calibrated_value);
648                     pos += 2;
649 
650                 }
651 
652                 if (instance->request_opcode == CP_OPCODE_START_OFFSET_COMPENSATION) break;
653                 little_endian_store_16(value, pos, instance->manufacturer_company_id);
654                 pos += 2;
655                 int data_len = (instance->num_manufacturer_specific_data < CYCLING_POWER_MANUFACTURER_SPECIFIC_DATA_MAX_SIZE) ? instance->num_manufacturer_specific_data : (CYCLING_POWER_MANUFACTURER_SPECIFIC_DATA_MAX_SIZE - 1);
656                 value[pos++] = data_len;
657                 memcpy(&value[pos], instance->manufacturer_specific_data, data_len);
658                 pos += data_len;
659                 value[pos++] = 0;
660                 break;
661             }
662             case CP_OPCODE_MASK_CYCLING_POWER_MEASUREMENT_CHARACTERISTIC_CONTENT:
663                 break;
664             default:
665                 break;
666         }
667     }
668     uint8_t status = att_server_indicate(instance->con_handle, instance->control_point_value_handle, &value[0], pos);
669     if (status == ERROR_CODE_SUCCESS){
670         instance->w4_indication_complete = 1;
671         // printf("cycling_power_service_response_can_send_now: set w4_indication_complete\n");
672         // printf("can_send_now set opcode to CP_OPCODE_IDLE\n");
673         instance->request_opcode = CP_OPCODE_IDLE;
674     } else {
675         log_error("can_send_now failed 0x%2x", status);
676     }
677 }
678 
679 static int cycling_power_service_write_callback(hci_con_handle_t con_handle, uint16_t attribute_handle, uint16_t transaction_mode, uint16_t offset, uint8_t *buffer, uint16_t buffer_size){
680     UNUSED(con_handle);
681     UNUSED(transaction_mode);
682     UNUSED(offset);
683     UNUSED(buffer_size);
684     int i;
685     cycling_power_sensor_location_t location;
686     cycling_power_t * instance = &cycling_power;
687 
688     // printf("cycling_power_service_write_callback: attr handle 0x%02x\n", attribute_handle);
689     if (attribute_handle == instance->measurement_client_configuration_descriptor_handle){
690         if (buffer_size < 2){
691             return ATT_ERROR_INVALID_OFFSET;
692         }
693         instance->measurement_client_configuration_descriptor_notify = little_endian_read_16(buffer, 0);
694         instance->con_handle = con_handle;
695         log_info("cycling_power_service_write_callback: measurement enabled %d", instance->measurement_client_configuration_descriptor_notify);
696         return 0;
697     }
698 
699     if (attribute_handle == instance->measurement_server_configuration_descriptor_handle){
700         if (buffer_size < 2){
701             return ATT_ERROR_INVALID_OFFSET;
702         }
703         instance->measurement_server_configuration_descriptor_broadcast = little_endian_read_16(buffer, 0);
704         instance->con_handle = con_handle;
705         uint8_t event[5];
706         int index = 0;
707         event[index++] = HCI_EVENT_GATTSERVICE_META;
708         event[index++] = sizeof(event) - 2;
709 
710         if (instance->measurement_server_configuration_descriptor_broadcast){
711             event[index++] = GATTSERVICE_SUBEVENT_CYCLING_POWER_BROADCAST_START;
712             log_info("cycling_power_service_write_callback: start broadcast");
713         } else {
714             event[index++] = GATTSERVICE_SUBEVENT_CYCLING_POWER_BROADCAST_STOP;
715             log_info("cycling_power_service_write_callback: stop broadcast");
716         }
717         little_endian_store_16(event, index, con_handle);
718         index += 2;
719         (*instance->calibration_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
720         return 0;
721     }
722 
723     if (attribute_handle == instance->vector_client_configuration_descriptor_handle){
724         if (buffer_size < 2){
725             return ATT_ERROR_INVALID_OFFSET;
726         }
727         instance->con_handle = con_handle;
728 
729 #ifdef ENABLE_ATT_DELAYED_RESPONSE
730         switch (instance->con_interval_status){
731             case CP_CONNECTION_INTERVAL_STATUS_REJECTED:
732                 return CYCLING_POWER_ERROR_CODE_INAPPROPRIATE_CONNECTION_PARAMETERS;
733 
734             case CP_CONNECTION_INTERVAL_STATUS_ACCEPTED:
735             case CP_CONNECTION_INTERVAL_STATUS_RECEIVED:
736                 if ((instance->con_interval > instance->con_interval_max) || (instance->con_interval < instance->con_interval_min)){
737                     instance->con_interval_status = CP_CONNECTION_INTERVAL_STATUS_W4_L2CAP_RESPONSE;
738                     gap_request_connection_parameter_update(instance->con_handle, instance->con_interval_min, instance->con_interval_max, 4, 100);    // 15 ms, 4, 1s
739                     return ATT_ERROR_WRITE_RESPONSE_PENDING;
740                 }
741                 instance->vector_client_configuration_descriptor_notify = little_endian_read_16(buffer, 0);
742                 return 0;
743             default:
744                 return ATT_ERROR_WRITE_RESPONSE_PENDING;
745 
746         }
747 #endif
748     }
749 
750     if (attribute_handle == instance->control_point_client_configuration_descriptor_handle){
751         if (buffer_size < 2){
752             return ATT_ERROR_INVALID_OFFSET;
753         }
754         instance->control_point_client_configuration_descriptor_indicate = little_endian_read_16(buffer, 0);
755         instance->con_handle = con_handle;
756         log_info("cycling_power_service_write_callback: indication enabled %d", instance->control_point_client_configuration_descriptor_indicate);
757         return 0;
758     }
759 
760     if (attribute_handle == instance->feature_value_handle){
761         if (buffer_size < 4){
762             return ATT_ERROR_INVALID_OFFSET;
763         }
764         instance->feature_flags = little_endian_read_32(buffer, 0);
765         return 0;
766     }
767 
768     if (attribute_handle == instance->control_point_value_handle){
769         if (instance->control_point_client_configuration_descriptor_indicate == 0) return CYCLING_POWER_ERROR_CODE_CCC_DESCRIPTOR_IMPROPERLY_CONFIGURED;
770         if (instance->w4_indication_complete != 0){
771             return CYCLING_POWER_ERROR_CODE_PROCEDURE_ALREADY_IN_PROGRESS;
772         }
773         int pos = 0;
774         instance->request_opcode = (cycling_power_opcode_t) buffer[pos++];
775         instance->response_value = CP_RESPONSE_VALUE_OP_CODE_NOT_SUPPORTED;
776 
777         switch (instance->request_opcode){
778             case CP_OPCODE_SET_CUMULATIVE_VALUE:
779                 if (!has_feature(CP_FEATURE_FLAG_WHEEL_REVOLUTION_DATA_SUPPORTED)) break;
780                 instance->cumulative_wheel_revolutions = little_endian_read_32(buffer, pos);
781                 instance->response_value = CP_RESPONSE_VALUE_SUCCESS;
782                 break;
783 
784             case CP_OPCODE_REQUEST_SUPPORTED_SENSOR_LOCATIONS:
785                 if (!has_feature(CP_FEATURE_FLAG_MULTIPLE_SENSOR_LOCATIONS_SUPPORTED)) break;
786                 instance->response_value = CP_RESPONSE_VALUE_SUCCESS;
787                 break;
788 
789             case CP_OPCODE_UPDATE_SENSOR_LOCATION:
790                 if (!has_feature(CP_FEATURE_FLAG_MULTIPLE_SENSOR_LOCATIONS_SUPPORTED)) break;
791                 location = (cycling_power_sensor_location_t) buffer[pos];
792                 instance->response_value = CP_RESPONSE_VALUE_INVALID_PARAMETER;
793                 for (i=0; i<instance->num_supported_sensor_locations; i++){
794                     if (instance->supported_sensor_locations[i] == location){
795                         instance->sensor_location = location;
796                         instance->response_value = CP_RESPONSE_VALUE_SUCCESS;
797                         break;
798                     }
799                 }
800                 break;
801 
802             case CP_OPCODE_REQUEST_CRANK_LENGTH:
803                 if (!has_feature(CP_FEATURE_FLAG_CRANK_LENGTH_ADJUSTMENT_SUPPORTED)) break;
804                 instance->response_value = CP_RESPONSE_VALUE_SUCCESS;
805                 break;
806             case CP_OPCODE_SET_CRANK_LENGTH:
807                 if (!has_feature(CP_FEATURE_FLAG_CRANK_LENGTH_ADJUSTMENT_SUPPORTED)) break;
808                 instance->crank_length_mm = little_endian_read_16(buffer, pos);
809                 instance->response_value = CP_RESPONSE_VALUE_SUCCESS;
810                 break;
811 
812             case CP_OPCODE_REQUEST_CHAIN_LENGTH:
813                 if (!has_feature(CP_FEATURE_FLAG_CHAIN_LENGTH_ADJUSTMENT_SUPPORTED)) break;
814                 instance->response_value = CP_RESPONSE_VALUE_SUCCESS;
815                 break;
816             case CP_OPCODE_SET_CHAIN_LENGTH:
817                 if (!has_feature(CP_FEATURE_FLAG_CHAIN_LENGTH_ADJUSTMENT_SUPPORTED)) break;
818                 instance->chain_length_mm = little_endian_read_16(buffer, pos);
819                 instance->response_value = CP_RESPONSE_VALUE_SUCCESS;
820                 break;
821 
822             case CP_OPCODE_REQUEST_CHAIN_WEIGHT:
823                 if (!has_feature(CP_FEATURE_FLAG_CHAIN_WEIGHT_ADJUSTMENT_SUPPORTED)) break;
824                 instance->response_value = CP_RESPONSE_VALUE_SUCCESS;
825                 break;
826             case CP_OPCODE_SET_CHAIN_WEIGHT:
827                 if (!has_feature(CP_FEATURE_FLAG_CHAIN_WEIGHT_ADJUSTMENT_SUPPORTED)) break;
828                 instance->chain_weight_g = little_endian_read_16(buffer, pos);
829                 instance->response_value = CP_RESPONSE_VALUE_SUCCESS;
830                 break;
831 
832             case CP_OPCODE_REQUEST_SPAN_LENGTH:
833                 if (!has_feature(CP_FEATURE_FLAG_SPAN_LENGTH_ADJUSTMENT_SUPPORTED)) break;
834                 instance->response_value = CP_RESPONSE_VALUE_SUCCESS;
835                 break;
836             case CP_OPCODE_SET_SPAN_LENGTH:
837                 if (!has_feature(CP_FEATURE_FLAG_SPAN_LENGTH_ADJUSTMENT_SUPPORTED)) break;
838                 instance->span_length_mm = little_endian_read_16(buffer, pos);
839                 instance->response_value = CP_RESPONSE_VALUE_SUCCESS;
840                 break;
841 
842             case CP_OPCODE_REQUEST_FACTORY_CALIBRATION_DATE:
843                 if (!has_feature(CP_FEATURE_FLAG_FACTORY_CALIBRATION_DATE_SUPPORTED)) break;
844                 instance->response_value = CP_RESPONSE_VALUE_SUCCESS;
845                 break;
846 
847             case CP_OPCODE_REQUEST_SAMPLING_RATE:
848                 if (!instance->vector_value_handle) break;
849                 instance->response_value = CP_RESPONSE_VALUE_SUCCESS;
850                 break;
851 
852             case CP_OPCODE_START_OFFSET_COMPENSATION:
853             case CP_OPCODE_START_ENHANCED_OFFSET_COMPENSATION:
854                 if (!has_feature(CP_FEATURE_FLAG_OFFSET_COMPENSATION_SUPPORTED)){
855                     instance->response_value = CP_RESPONSE_VALUE_INVALID_PARAMETER;
856                     break;
857                 }
858                 if (has_feature(CP_FEATURE_FLAG_EXTREME_MAGNITUDES_SUPPORTED) &&
859                         ((has_feature(CP_FEATURE_FLAG_SENSOR_MEASUREMENT_CONTEXT) == CP_SENSOR_MEASUREMENT_CONTEXT_FORCE) ||
860                          (has_feature(CP_FEATURE_FLAG_SENSOR_MEASUREMENT_CONTEXT) == CP_SENSOR_MEASUREMENT_CONTEXT_TORQUE))
861                 ){
862                     // printf("start offset compensation procedure, enhanced %d\n", (instance->request_opcode == CP_OPCODE_START_ENHANCED_OFFSET_COMPENSATION));
863                     uint8_t event[7];
864                     int index = 0;
865                     event[index++] = HCI_EVENT_GATTSERVICE_META;
866                     event[index++] = sizeof(event) - 2;
867                     event[index++] = GATTSERVICE_SUBEVENT_CYCLING_POWER_START_CALIBRATION;
868                     little_endian_store_16(event, index, con_handle);
869                     index += 2;
870                     event[index++] = has_feature(CP_FEATURE_FLAG_SENSOR_MEASUREMENT_CONTEXT) == CP_SENSOR_MEASUREMENT_CONTEXT_TORQUE;
871                     event[index++] = (instance->request_opcode == CP_OPCODE_START_ENHANCED_OFFSET_COMPENSATION);
872                     instance->response_value = CP_RESPONSE_VALUE_W4_VALUE_AVAILABLE;
873                     (*instance->calibration_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
874                     return 0;
875                 }
876                 instance->current_force_magnitude_newton = 0xffff;
877                 instance->current_torque_magnitude_newton_m = 0xffff;
878                 break;
879 
880             case CP_OPCODE_MASK_CYCLING_POWER_MEASUREMENT_CHARACTERISTIC_CONTENT:{
881                 if (!has_feature(CP_FEATURE_FLAG_CYCLING_POWER_MEASUREMENT_CHARACTERISTIC_CONTENT_MASKING_SUPPORTED)) break;
882                 uint16_t mask_bitmap = little_endian_read_16(buffer, pos);
883                 uint16_t masked_measurement_flags = instance->default_measurement_flags;
884                 uint16_t index = 0;
885 
886                 for (i = 0; i < CP_MASK_BIT_RESERVED; i++){
887                     uint8_t clear_bit = (mask_bitmap & (1 << i)) ? 1 : 0;
888 
889                     masked_measurement_flags &= ~(clear_bit << index);
890                     index++;
891                     // following measurement flags have additional flag
892                     switch ((cycling_power_mask_bit_t)i){
893                         case CP_MASK_BIT_PEDAL_POWER_BALANCE:
894                         case CP_MASK_BIT_ACCUMULATED_TORQUE:
895                         case CP_MASK_BIT_EXTREME_MAGNITUDES:
896                             masked_measurement_flags &= ~(clear_bit << index);
897                             index++;
898                             break;
899                         default:
900                             break;
901                     }
902                 }
903                 instance->masked_measurement_flags = masked_measurement_flags;
904                 instance->response_value = CP_RESPONSE_VALUE_SUCCESS;
905                 break;
906             }
907             default:
908                 break;
909         }
910 
911         if (instance->control_point_client_configuration_descriptor_indicate){
912             instance->control_point_indicate_callback.callback = &cycling_power_service_response_can_send_now;
913             instance->control_point_indicate_callback.context  = (void*) instance;
914             att_server_register_can_send_now_callback(&instance->control_point_indicate_callback, instance->con_handle);
915         }
916         return 0;
917     }
918     return 0;
919 }
920 
921 static void packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
922     UNUSED(channel);
923     UNUSED(size);
924     cycling_power_t * instance = &cycling_power;
925     uint8_t event_type = hci_event_packet_get_type(packet);
926     uint16_t con_handle;
927 
928     if (packet_type != HCI_EVENT_PACKET) return;
929     switch (event_type){
930         case HCI_EVENT_LE_META:
931             switch (hci_event_le_meta_get_subevent_code(packet)){
932                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
933                     instance->con_handle = hci_subevent_le_connection_complete_get_connection_handle(packet);
934                     // print connection parameters (without using float operations)
935                     instance->con_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
936                     // printf("Initial Connection Interval: %u, %u.%02u ms\n", instance->con_interval, instance->con_interval * 125 / 100, 25 * (instance->con_interval & 3));
937                     // printf("Initial Connection Latency: %u\n", hci_subevent_le_connection_complete_get_conn_latency(packet));
938                     instance->con_interval_status = CP_CONNECTION_INTERVAL_STATUS_RECEIVED;
939                     break;
940                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
941                     if (instance->con_interval_status != CP_CONNECTION_INTERVAL_STATUS_W4_UPDATE) return;
942 
943                     if ((instance->con_interval > instance->con_interval_max) || (instance->con_interval < instance->con_interval_min)){
944                         instance->con_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
945                         // printf("Updated Connection Interval: %u, %u.%02u ms\n", instance->con_interval, instance->con_interval * 125 / 100, 25 * (instance->con_interval & 3));
946                         // printf("Updated Connection Latency: %u\n", hci_subevent_le_connection_update_complete_get_conn_latency(packet));
947                         instance->con_interval_status = CP_CONNECTION_INTERVAL_STATUS_ACCEPTED;
948                     } else {
949                         instance->con_interval_status = CP_CONNECTION_INTERVAL_STATUS_REJECTED;
950                     }
951                     att_server_response_ready(l2cap_event_connection_parameter_update_response_get_handle(packet));
952                     break;
953                 default:
954                     break;
955             }
956             break;
957         case L2CAP_EVENT_CONNECTION_PARAMETER_UPDATE_RESPONSE:
958             if (instance->con_interval_status != CP_CONNECTION_INTERVAL_STATUS_W4_L2CAP_RESPONSE) return;
959 
960             // printf("L2CAP Connection Parameter Update Complete, response: %x\n", l2cap_event_connection_parameter_update_response_get_result(packet));
961             if (l2cap_event_connection_parameter_update_response_get_result(packet) == ERROR_CODE_SUCCESS){
962                 instance->con_interval_status = CP_CONNECTION_INTERVAL_STATUS_W4_UPDATE;
963             } else {
964                 instance->con_interval_status = CP_CONNECTION_INTERVAL_STATUS_REJECTED;
965                 att_server_response_ready(l2cap_event_connection_parameter_update_response_get_handle(packet));
966             }
967             break;
968 
969         case HCI_EVENT_DISCONNECTION_COMPLETE:{
970             if (!instance) return;
971             con_handle = hci_event_disconnection_complete_get_connection_handle(packet);
972             if (con_handle == HCI_CON_HANDLE_INVALID) return;
973 
974             instance->masked_measurement_flags = CYCLING_POWER_MEASUREMENT_FLAGS_CLEARED;
975             instance->w4_indication_complete = 0;
976 
977             uint8_t event[5];
978             int index = 0;
979             event[index++] = HCI_EVENT_GATTSERVICE_META;
980             event[index++] = sizeof(event) - 2;
981 
982             event[index++] = GATTSERVICE_SUBEVENT_CYCLING_POWER_BROADCAST_STOP;
983             little_endian_store_16(event, index, con_handle);
984             index += 2;
985             (*instance->calibration_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
986 
987             break;
988         }
989         case ATT_EVENT_HANDLE_VALUE_INDICATION_COMPLETE:
990             instance->w4_indication_complete = 0;
991             break;
992         default:
993             break;
994      }
995 }
996 
997 void cycling_power_service_server_init(uint32_t feature_flags,
998     cycling_power_pedal_power_balance_reference_t reference, cycling_power_torque_source_t torque_source,
999     cycling_power_sensor_location_t * supported_sensor_locations, uint16_t num_supported_sensor_locations,
1000     cycling_power_sensor_location_t   current_sensor_location){
1001 
1002     cycling_power_t * instance = &cycling_power;
1003     // TODO: remove hardcoded initialization
1004     instance->con_interval_min = 6;
1005     instance->con_interval_max = 6;
1006     instance->con_interval_status = CP_CONNECTION_INTERVAL_STATUS_NONE;
1007     instance->w4_indication_complete = 0;
1008     hci_event_callback_registration.callback = &packet_handler;
1009     hci_add_event_handler(&hci_event_callback_registration);
1010     l2cap_register_packet_handler(&packet_handler);
1011 
1012     instance->sensor_location = current_sensor_location;
1013     instance->num_supported_sensor_locations = 0;
1014     if (supported_sensor_locations != NULL){
1015         instance->num_supported_sensor_locations = num_supported_sensor_locations;
1016         instance->supported_sensor_locations = supported_sensor_locations;
1017     }
1018 
1019     instance->feature_flags = feature_flags;
1020     instance->default_measurement_flags = CYCLING_POWER_MEASUREMENT_FLAGS_CLEARED;
1021     instance->masked_measurement_flags  = CYCLING_POWER_MEASUREMENT_FLAGS_CLEARED;
1022     instance->pedal_power_balance_reference = reference;
1023     instance->torque_source = torque_source;
1024 
1025     // get service handle range
1026     uint16_t start_handle = 0;
1027     uint16_t end_handle   = 0xffff;
1028     int service_found = gatt_server_get_get_handle_range_for_service_with_uuid16(ORG_BLUETOOTH_SERVICE_CYCLING_POWER, &start_handle, &end_handle);
1029     if (!service_found){
1030         log_error("no service found\n");
1031         return;
1032     }
1033     // get CP Mesurement characteristic value handle and client configuration handle
1034     instance->measurement_value_handle = gatt_server_get_value_handle_for_characteristic_with_uuid16(start_handle, end_handle, ORG_BLUETOOTH_CHARACTERISTIC_CYCLING_POWER_MEASUREMENT);
1035     instance->measurement_client_configuration_descriptor_handle = gatt_server_get_client_configuration_handle_for_characteristic_with_uuid16(start_handle, end_handle, ORG_BLUETOOTH_CHARACTERISTIC_CYCLING_POWER_MEASUREMENT);
1036     instance->measurement_server_configuration_descriptor_handle = gatt_server_get_server_configuration_handle_for_characteristic_with_uuid16(start_handle, end_handle, ORG_BLUETOOTH_CHARACTERISTIC_CYCLING_POWER_MEASUREMENT);
1037 
1038     // get CP Feature characteristic value handle and client configuration handle
1039     instance->feature_value_handle = gatt_server_get_value_handle_for_characteristic_with_uuid16(start_handle, end_handle, ORG_BLUETOOTH_CHARACTERISTIC_CYCLING_POWER_FEATURE);
1040     // get CP Sensor Location characteristic value handle and client configuration handle
1041     instance->sensor_location_value_handle = gatt_server_get_value_handle_for_characteristic_with_uuid16(start_handle, end_handle, ORG_BLUETOOTH_CHARACTERISTIC_SENSOR_LOCATION);
1042 
1043     // get CP Vector characteristic value handle and client configuration handle
1044     instance->vector_value_handle = gatt_server_get_value_handle_for_characteristic_with_uuid16(start_handle, end_handle, ORG_BLUETOOTH_CHARACTERISTIC_CYCLING_POWER_VECTOR);
1045     instance->vector_client_configuration_descriptor_handle = gatt_server_get_client_configuration_handle_for_characteristic_with_uuid16(start_handle, end_handle, ORG_BLUETOOTH_CHARACTERISTIC_CYCLING_POWER_VECTOR);
1046 
1047     // get Body Sensor Location characteristic value handle and client configuration handle
1048     instance->sensor_location_value_handle = gatt_server_get_value_handle_for_characteristic_with_uuid16(start_handle, end_handle, ORG_BLUETOOTH_CHARACTERISTIC_SENSOR_LOCATION);
1049 
1050     // get SP Control Point characteristic value handle and client configuration handle
1051     instance->control_point_value_handle = gatt_server_get_value_handle_for_characteristic_with_uuid16(start_handle, end_handle, ORG_BLUETOOTH_CHARACTERISTIC_CYCLING_POWER_CONTROL_POINT);
1052     instance->control_point_client_configuration_descriptor_handle = gatt_server_get_client_configuration_handle_for_characteristic_with_uuid16(start_handle, end_handle, ORG_BLUETOOTH_CHARACTERISTIC_CYCLING_POWER_CONTROL_POINT);
1053 
1054     log_info("Measurement     value handle 0x%02x", instance->measurement_value_handle);
1055     log_info("M. Client Cfg   value handle 0x%02x", instance->measurement_client_configuration_descriptor_handle);
1056     log_info("M. Server Cfg   value handle 0x%02x", instance->measurement_server_configuration_descriptor_handle);
1057 
1058     log_info("Feature         value handle 0x%02x", instance->feature_value_handle);
1059     log_info("Sensor location value handle 0x%02x", instance->sensor_location_value_handle);
1060 
1061     log_info("Vector          value handle 0x%02x", instance->vector_value_handle);
1062     log_info("Vector Cfg.     value handle 0x%02x", instance->vector_client_configuration_descriptor_handle);
1063 
1064     log_info("Control Point   value handle 0x%02x", instance->control_point_value_handle);
1065     log_info("Control P. Cfg. value handle 0x%02x", instance->control_point_client_configuration_descriptor_handle);
1066 
1067     cycling_power_service.start_handle   = start_handle;
1068     cycling_power_service.end_handle     = end_handle;
1069     cycling_power_service.read_callback  = &cycling_power_service_read_callback;
1070     cycling_power_service.write_callback = &cycling_power_service_write_callback;
1071     cycling_power_service.packet_handler = &packet_handler;
1072     att_server_register_service_handler(&cycling_power_service);
1073 }
1074 
1075 
1076 void cycling_power_service_server_add_torque(int16_t torque_m){
1077     cycling_power_t * instance = &cycling_power;
1078     instance->accumulated_torque_m += torque_m;
1079 }
1080 
1081 void cycling_power_service_server_add_wheel_revolution(int32_t wheel_revolution, uint16_t wheel_event_time_s){
1082     cycling_power_t * instance = &cycling_power;
1083     instance->last_wheel_event_time_s = wheel_event_time_s;
1084     if (wheel_revolution < 0){
1085         if (instance->cumulative_wheel_revolutions > -wheel_revolution){
1086             instance->cumulative_wheel_revolutions += wheel_revolution;
1087         } else {
1088             instance->cumulative_wheel_revolutions = 0;
1089         }
1090     } else {
1091         if (instance->cumulative_wheel_revolutions < (0xffffffff - wheel_revolution)){
1092             instance->cumulative_wheel_revolutions += wheel_revolution;
1093         } else {
1094             instance->cumulative_wheel_revolutions = 0xffffffff;
1095         }
1096     }
1097 }
1098 
1099 void cycling_power_service_server_add_crank_revolution(uint16_t crank_revolution, uint16_t crank_event_time_s){
1100     cycling_power_t * instance = &cycling_power;
1101     instance->last_crank_event_time_s = crank_event_time_s;
1102     instance->cumulative_crank_revolutions += crank_revolution;
1103 }
1104 
1105 void cycling_power_service_add_energy(uint16_t energy_kJ){
1106     cycling_power_t * instance = &cycling_power;
1107     if (instance->accumulated_energy_kJ <= (0xffff - energy_kJ)){
1108         instance->accumulated_energy_kJ += energy_kJ;
1109     } else {
1110         instance->accumulated_energy_kJ = 0xffff;
1111     }
1112     // printf("energy %d\n", instance->accumulated_energy_kJ);
1113 }
1114 
1115 void cycling_power_service_server_set_instantaneous_power(int16_t instantaneous_power_watt){
1116     cycling_power_t * instance = &cycling_power;
1117     instance->instantaneous_power_watt = instantaneous_power_watt;
1118 }
1119 
1120 void cycling_power_service_server_set_pedal_power_balance(uint8_t pedal_power_balance_percentage){
1121     cycling_power_t * instance = &cycling_power;
1122     instance->pedal_power_balance_percentage = pedal_power_balance_percentage;
1123 }
1124 
1125 void cycling_power_service_server_set_force_magnitude_values(int force_magnitude_count, int16_t * force_magnitude_newton_array){
1126     cycling_power_t * instance = &cycling_power;
1127     instance->force_magnitude_count = force_magnitude_count;
1128     instance->vector_instantaneous_force_magnitude_newton_array = force_magnitude_newton_array;
1129 }
1130 
1131 void cycling_power_service_server_set_torque_magnitude_values(int torque_magnitude_count, int16_t * torque_magnitude_newton_array){
1132     cycling_power_t * instance = &cycling_power;
1133     instance->torque_magnitude_count = torque_magnitude_count;
1134     instance->vector_instantaneous_torque_magnitude_newton_per_m_array = torque_magnitude_newton_array;
1135 }
1136 
1137 void cycling_power_service_server_set_first_crank_measurement_angle(uint16_t first_crank_measurement_angle_deg){
1138     cycling_power_t * instance = &cycling_power;
1139     instance->vector_first_crank_measurement_angle_deg = first_crank_measurement_angle_deg;
1140 }
1141 
1142 void cycling_power_service_server_set_instantaneous_measurement_direction(cycling_power_instantaneous_measurement_direction_t direction){
1143     cycling_power_t * instance = &cycling_power;
1144     instance->vector_instantaneous_measurement_direction = direction;
1145 }
1146 
1147 void cycling_power_service_server_set_force_magnitude(int16_t min_force_magnitude_newton, int16_t max_force_magnitude_newton){
1148     cycling_power_t * instance = &cycling_power;
1149     instance->minimum_force_magnitude_newton = min_force_magnitude_newton;
1150     instance->maximum_force_magnitude_newton = max_force_magnitude_newton;
1151 }
1152 
1153 void cycling_power_service_server_set_torque_magnitude(int16_t min_torque_magnitude_newton, int16_t max_torque_magnitude_newton){
1154     cycling_power_t * instance = &cycling_power;
1155     instance->minimum_torque_magnitude_newton_m = min_torque_magnitude_newton;
1156     instance->maximum_torque_magnitude_newton_m = max_torque_magnitude_newton;
1157 }
1158 
1159 void cycling_power_service_server_set_angle(uint16_t min_angle_deg, uint16_t max_angle_deg){
1160     cycling_power_t * instance = &cycling_power;
1161     instance->minimum_angle_deg = min_angle_deg;
1162     instance->maximum_angle_deg = max_angle_deg;
1163 }
1164 
1165 void cycling_power_service_server_set_top_dead_spot_angle(uint16_t top_dead_spot_angle_deg){
1166     cycling_power_t * instance = &cycling_power;
1167     instance->top_dead_spot_angle_deg = top_dead_spot_angle_deg;
1168 }
1169 
1170 void cycling_power_service_server_set_bottom_dead_spot_angle(uint16_t bottom_dead_spot_angle_deg){
1171     cycling_power_t * instance = &cycling_power;
1172     instance->bottom_dead_spot_angle_deg = bottom_dead_spot_angle_deg;
1173 }
1174 
1175 static int gatt_date_is_valid(gatt_date_time_t date){
1176     if ((date.year != 0) && ((date.year < 1582) || (date.year > 9999))) return 0;
1177     if ((date.month != 0) && (date.month > 12)) return 0;
1178     if ((date.day != 0) && (date.day > 31)) return 0;
1179 
1180     if (date.hours > 23) return 0;
1181     if (date.minutes > 59) return 0;
1182     if (date.seconds > 59) return 0;
1183     return 1;
1184 }
1185 
1186 int cycling_power_service_server_set_factory_calibration_date(gatt_date_time_t date){
1187     if (!gatt_date_is_valid(date)) return 0;
1188 
1189     cycling_power_t * instance = &cycling_power;
1190     instance->factory_calibration_date = date;
1191     return 1;
1192 }
1193 
1194 void cycling_power_service_server_set_sampling_rate(uint8_t sampling_rate_hz){
1195     cycling_power_t * instance = &cycling_power;
1196     instance->sampling_rate_hz = sampling_rate_hz;
1197 }
1198 
1199 
1200 void cycling_power_service_server_update_values(void){
1201     cycling_power_t * instance = &cycling_power;
1202 
1203     if (instance->measurement_server_configuration_descriptor_broadcast){
1204         instance->measurement_broadcast_callback.callback = &cycling_power_service_broadcast_can_send_now;
1205         instance->measurement_broadcast_callback.context  = (void*) instance;
1206         att_server_register_can_send_now_callback(&instance->measurement_broadcast_callback, instance->con_handle);
1207     }
1208 
1209     if (instance->measurement_client_configuration_descriptor_notify){
1210         instance->measurement_notify_callback.callback = &cycling_power_service_measurement_can_send_now;
1211         instance->measurement_notify_callback.context  = (void*) instance;
1212         att_server_register_can_send_now_callback(&instance->measurement_notify_callback, instance->con_handle);
1213     }
1214 
1215     if (instance->vector_client_configuration_descriptor_notify){
1216         instance->vector_notify_callback.callback = &cycling_power_service_vector_can_send_now;
1217         instance->vector_notify_callback.context  = (void*) instance;
1218         att_server_register_can_send_now_callback(&instance->vector_notify_callback, instance->con_handle);
1219     }
1220 }
1221 
1222 void cycling_power_service_server_packet_handler(btstack_packet_handler_t callback){
1223     if (callback == NULL){
1224         log_error("cycling_power_service_server_packet_handler called with NULL callback");
1225         return;
1226     }
1227     cycling_power_t * instance = &cycling_power;
1228     instance->calibration_callback = callback;
1229 }
1230 
1231 void cycling_power_server_calibration_done(cycling_power_sensor_measurement_context_t measurement_type, uint16_t calibrated_value){
1232     cycling_power_t * instance = &cycling_power;
1233     if (instance->response_value != CP_RESPONSE_VALUE_W4_VALUE_AVAILABLE){
1234         printf("cycling_power_server_calibration_done : CP_RESPONSE_VALUE_W4_VALUE_AVAILABLE con_handle 0x%02x\n", instance->con_handle);
1235         return;
1236     }
1237     instance->response_value = CP_RESPONSE_VALUE_SUCCESS;
1238 
1239     switch (measurement_type){
1240         case CP_SENSOR_MEASUREMENT_CONTEXT_FORCE:
1241             instance->current_force_magnitude_newton = calibrated_value;
1242             break;
1243         case CP_SENSOR_MEASUREMENT_CONTEXT_TORQUE:
1244             instance->current_torque_magnitude_newton_m = calibrated_value;
1245             break;
1246         default:
1247             instance->response_value = CP_RESPONSE_VALUE_INVALID_PARAMETER;
1248             break;
1249     }
1250 
1251     if (instance->response_value == CP_RESPONSE_VALUE_SUCCESS){
1252         switch (calibrated_value){
1253             case CP_CALIBRATION_STATUS_INCORRECT_CALIBRATION_POSITION:
1254             case CP_CALIBRATION_STATUS_MANUFACTURER_SPECIFIC_ERROR_FOLLOWS:
1255                 instance->response_value = CP_RESPONSE_VALUE_OPERATION_FAILED;
1256                 instance->response_value = CP_RESPONSE_VALUE_OPERATION_FAILED;
1257                 break;
1258             default:
1259                 break;
1260         }
1261     }
1262 
1263     if (instance->control_point_client_configuration_descriptor_indicate){
1264         instance->control_point_indicate_callback.callback = &cycling_power_service_response_can_send_now;
1265         instance->control_point_indicate_callback.context  = (void*) instance;
1266         att_server_register_can_send_now_callback(&instance->control_point_indicate_callback, instance->con_handle);
1267     }
1268 }
1269 
1270 void cycling_power_server_enhanced_calibration_done(cycling_power_sensor_measurement_context_t measurement_type,
1271                 uint16_t calibrated_value, uint16_t manufacturer_company_id,
1272                 uint8_t num_manufacturer_specific_data, uint8_t * manufacturer_specific_data){
1273     cycling_power_t * instance = &cycling_power;
1274     if (instance->response_value != CP_RESPONSE_VALUE_W4_VALUE_AVAILABLE) return;
1275     instance->response_value = CP_RESPONSE_VALUE_SUCCESS;
1276 
1277     switch (measurement_type){
1278         case CP_SENSOR_MEASUREMENT_CONTEXT_FORCE:
1279             instance->current_force_magnitude_newton = calibrated_value;
1280             break;
1281         case CP_SENSOR_MEASUREMENT_CONTEXT_TORQUE:
1282             instance->current_torque_magnitude_newton_m = calibrated_value;
1283             break;
1284         default:
1285             instance->response_value = CP_RESPONSE_VALUE_INVALID_PARAMETER;
1286             break;
1287     }
1288 
1289     if (instance->response_value == CP_RESPONSE_VALUE_SUCCESS){
1290         switch (calibrated_value){
1291             case CP_CALIBRATION_STATUS_INCORRECT_CALIBRATION_POSITION:
1292             case CP_CALIBRATION_STATUS_MANUFACTURER_SPECIFIC_ERROR_FOLLOWS:
1293                 instance->response_value = CP_RESPONSE_VALUE_OPERATION_FAILED;
1294                 instance->response_value = CP_RESPONSE_VALUE_OPERATION_FAILED;
1295                 break;
1296             default:
1297                 break;
1298         }
1299         instance->manufacturer_company_id = manufacturer_company_id;
1300         instance->num_manufacturer_specific_data = num_manufacturer_specific_data;
1301         instance->manufacturer_specific_data = manufacturer_specific_data;
1302     }
1303 
1304     if (instance->control_point_client_configuration_descriptor_indicate){
1305         instance->control_point_indicate_callback.callback = &cycling_power_service_response_can_send_now;
1306         instance->control_point_indicate_callback.context  = (void*) instance;
1307         att_server_register_can_send_now_callback(&instance->control_point_indicate_callback, instance->con_handle);
1308     }
1309 }
1310