xref: /btstack/src/ble/gatt-service/hids_device.c (revision 3a19f7e295cb91ddc14d9634b76a83dbe469d59f)
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__ "hids_device.c"
39 
40 /**
41  * Implementation of the GATT HIDS Device
42  * To use with your application, add '#import <hids.gatt>' to your .gatt file
43  */
44 
45 #include "hids_device.h"
46 
47 #include "ble/att_db.h"
48 #include "ble/att_server.h"
49 #include "bluetooth_gatt.h"
50 #include "btstack_util.h"
51 #include "btstack_debug.h"
52 
53 #define HIDS_DEVICE_ERROR_CODE_INAPPROPRIATE_CONNECTION_PARAMETERS    0x80
54 
55 static hids_device_report_t hid_reports_storage[3];
56 
57 typedef struct{
58     uint16_t        con_handle;
59 
60     uint8_t         hid_country_code;
61     const uint8_t * hid_descriptor;
62     uint16_t        hid_descriptor_size;
63 
64     uint16_t        hid_report_map_handle;
65     uint8_t         hid_protocol_mode;
66     uint16_t        hid_protocol_mode_value_handle;
67 
68     uint16_t        hid_boot_mouse_input_value_handle;
69     uint16_t        hid_boot_mouse_input_client_configuration_handle;
70     uint16_t        hid_boot_mouse_input_client_configuration_value;
71 
72     uint16_t        hid_boot_keyboard_input_value_handle;
73     uint16_t        hid_boot_keyboard_input_client_configuration_handle;
74     uint16_t        hid_boot_keyboard_input_client_configuration_value;
75 
76     hids_device_report_t * hid_reports;
77 
78     uint8_t         hid_input_reports_num;
79     uint8_t         hid_output_reports_num;
80     uint8_t         hid_feature_reports_num;
81 
82     uint16_t        hid_control_point_value_handle;
83     uint8_t         hid_control_point_suspend;
84 
85     btstack_context_callback_registration_t  battery_callback;
86 } hids_device_t;
87 
88 static hids_device_t hids_device;
89 
90 static btstack_packet_handler_t packet_handler;
91 static att_service_handler_t hid_service;
92 
93 // TODO: store hids device connection into list
94 static hids_device_t * hids_device_get_instance_for_con_handle(uint16_t con_handle){
95     UNUSED(con_handle);
96     return &hids_device;
97 }
98 
99 static hids_device_t * hids_device_create_instance(void){
100     memset(&hids_device, 0, sizeof(hids_device_t));
101     return &hids_device;
102 }
103 
104 static hids_device_report_t * hids_device_get_report_for_client_configuration_handle(hids_device_t * device, uint16_t client_configuration_handle){
105     uint8_t pos = 0;
106     while (pos < (device->hid_input_reports_num + device->hid_output_reports_num + device->hid_feature_reports_num)){
107         if (device->hid_reports[pos].client_configuration_handle == client_configuration_handle){
108             return &device->hid_reports[pos];
109         }
110     }
111     return NULL;
112 }
113 
114 static hids_device_report_t * hids_device_get_report_for_id(hids_device_t * device, uint16_t report_id){
115     uint8_t pos = 0;
116     while (pos < (device->hid_input_reports_num + device->hid_output_reports_num + device->hid_feature_reports_num)){
117         if (device->hid_reports[pos].id == report_id){
118             return &device->hid_reports[pos];
119         }
120     }
121     return NULL;
122 }
123 
124 static void hids_device_emit_event_with_uint8(uint8_t event, hci_con_handle_t con_handle, uint8_t value){
125     hids_device_t * instance = hids_device_get_instance_for_con_handle(con_handle);
126     if (!instance){
127         log_error("no instance for handle 0x%02x", con_handle);
128         return;
129     }
130 
131     if (!packet_handler) return;
132     uint8_t buffer[6];
133     buffer[0] = HCI_EVENT_HIDS_META;
134     buffer[1] = 4;
135     buffer[2] = event;
136     little_endian_store_16(buffer, 3, (uint16_t) con_handle);
137     buffer[5] = value;
138     (*packet_handler)(HCI_EVENT_PACKET, 0, buffer, sizeof(buffer));
139 }
140 
141 static void hids_device_emit_event(uint8_t event, hci_con_handle_t con_handle){
142     hids_device_t * instance = hids_device_get_instance_for_con_handle(con_handle);
143     if (!instance){
144         log_error("no instance for handle 0x%02x", con_handle);
145         return;
146     }
147 
148     if (!packet_handler) return;
149     uint8_t buffer[5];
150     buffer[0] = HCI_EVENT_HIDS_META;
151     buffer[1] = 4;
152     buffer[2] = event;
153     little_endian_store_16(buffer, 3, (uint16_t) con_handle);
154     (*packet_handler)(HCI_EVENT_PACKET, 0, buffer, sizeof(buffer));
155 }
156 
157 static void hids_device_can_send_now(void * context){
158     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) context;
159     // notify client
160     hids_device_t * instance = hids_device_get_instance_for_con_handle(con_handle);
161     if (!instance){
162         log_error("no instance for handle 0x%02x", con_handle);
163         return;
164     }
165 
166     if (!packet_handler) return;
167     uint8_t buffer[5];
168     buffer[0] = HCI_EVENT_HIDS_META;
169     buffer[1] = 3;
170     buffer[2] = HIDS_SUBEVENT_CAN_SEND_NOW;
171     little_endian_store_16(buffer, 3, (uint16_t) con_handle);
172     (*packet_handler)(HCI_EVENT_PACKET, 0, buffer, sizeof(buffer));
173 }
174 
175 // ATT Client Read Callback for Dynamic Data
176 // - if buffer == NULL, don't copy data, just return size of value
177 // - if buffer != NULL, copy data and return number bytes copied
178 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){
179     hids_device_t * instance = hids_device_get_instance_for_con_handle(con_handle);
180     if (!instance){
181         log_error("no instance for handle 0x%02x", con_handle);
182         return HIDS_DEVICE_ERROR_CODE_INAPPROPRIATE_CONNECTION_PARAMETERS;
183     }
184 
185     if (att_handle == instance->hid_protocol_mode_value_handle){
186         log_info("Read protocol mode");
187         return att_read_callback_handle_byte(instance->hid_protocol_mode, offset, buffer, buffer_size);
188     }
189 
190     if (att_handle == instance->hid_report_map_handle){
191         log_info("Read report map");
192         return att_read_callback_handle_blob(instance->hid_descriptor, instance->hid_descriptor_size, offset, buffer, buffer_size);
193     }
194 
195     if (att_handle == instance->hid_boot_mouse_input_client_configuration_handle){
196         return att_read_callback_handle_little_endian_16(instance->hid_boot_mouse_input_client_configuration_value, offset, buffer, buffer_size);
197     }
198 
199     if (att_handle == instance->hid_boot_keyboard_input_client_configuration_handle){
200         return att_read_callback_handle_little_endian_16(instance->hid_boot_keyboard_input_client_configuration_value, offset, buffer, buffer_size);
201     }
202 
203     if (att_handle == instance->hid_control_point_value_handle){
204         if (buffer && (buffer_size >= 1u)){
205             buffer[0] = instance->hid_control_point_suspend;
206         }
207         return 1;
208     }
209 
210     hids_device_report_t * report = hids_device_get_report_for_client_configuration_handle(instance, att_handle);
211     if (report != NULL){
212         return att_read_callback_handle_little_endian_16(report->client_configuration_value, offset, buffer, buffer_size);
213     }
214     return 0;
215 }
216 
217 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){
218     UNUSED(transaction_mode);
219     UNUSED(buffer_size);
220     UNUSED(offset);
221 
222     hids_device_t * instance = hids_device_get_instance_for_con_handle(con_handle);
223     if (!instance){
224         log_error("no instance for handle 0x%02x", con_handle);
225         return HIDS_DEVICE_ERROR_CODE_INAPPROPRIATE_CONNECTION_PARAMETERS;
226     }
227 
228     if (att_handle == instance->hid_boot_mouse_input_client_configuration_handle){
229         uint16_t new_value = little_endian_read_16(buffer, 0);
230         instance->hid_boot_mouse_input_client_configuration_value = new_value;
231         hids_device_emit_event_with_uint8(HIDS_SUBEVENT_BOOT_MOUSE_INPUT_REPORT_ENABLE, con_handle, (uint8_t) new_value);
232     }
233     if (att_handle == instance->hid_boot_keyboard_input_client_configuration_handle){
234         uint16_t new_value = little_endian_read_16(buffer, 0);
235         instance->hid_boot_keyboard_input_client_configuration_value = new_value;
236         hids_device_emit_event_with_uint8(HIDS_SUBEVENT_BOOT_KEYBOARD_INPUT_REPORT_ENABLE, con_handle, (uint8_t) new_value);
237     }
238 
239     if (att_handle == instance->hid_protocol_mode_value_handle){
240         instance->hid_protocol_mode = buffer[0];
241         log_info("Set protocol mode: %u", instance->hid_protocol_mode);
242         hids_device_emit_event_with_uint8(HIDS_SUBEVENT_PROTOCOL_MODE, con_handle, instance->hid_protocol_mode);
243     }
244 
245     if (att_handle == instance->hid_control_point_value_handle){
246         if (buffer_size < 1u){
247             return ATT_ERROR_INVALID_OFFSET;
248         }
249         instance->hid_control_point_suspend = buffer[0];
250         instance->con_handle = con_handle;
251         log_info("Set suspend tp: %u", instance->hid_control_point_suspend );
252         if (instance->hid_control_point_suspend == 0u){
253             hids_device_emit_event(HIDS_SUBEVENT_SUSPEND, con_handle);
254         } else if (instance->hid_control_point_suspend == 1u){
255             hids_device_emit_event(HIDS_SUBEVENT_EXIT_SUSPEND, con_handle);
256         }
257     }
258 
259     hids_device_report_t * report = hids_device_get_report_for_client_configuration_handle(instance, att_handle);
260     if (report != NULL){
261         uint16_t new_value = little_endian_read_16(buffer, 0);
262         report->client_configuration_value = new_value;
263         log_info("Enable Report (type %u) notifications: %x", (uint8_t) report->type, new_value);
264 
265         switch (report->type){
266             case HID_REPORT_TYPE_INPUT:
267                 hids_device_emit_event_with_uint8(HIDS_SUBEVENT_INPUT_REPORT_ENABLE, con_handle, (uint8_t) new_value);
268                 break;
269             case HID_REPORT_TYPE_OUTPUT:
270                 hids_device_emit_event_with_uint8(HIDS_SUBEVENT_OUTPUT_REPORT_ENABLE, con_handle, (uint8_t) new_value);
271                 break;
272             case HID_REPORT_TYPE_FEATURE:
273                 hids_device_emit_event_with_uint8(HIDS_SUBEVENT_FEATURE_REPORT_ENABLE, con_handle, (uint8_t) new_value);
274                 break;
275             default:
276                 btstack_unreachable();
277                 break;
278         }
279     }
280     return 0;
281 }
282 
283 void hids_device_init_with_storage(uint8_t hid_country_code, const uint8_t * hid_descriptor, uint16_t hid_descriptor_size,
284     uint16_t num_reports, hids_device_report_t * report_storage){
285 
286     hids_device_t * instance = hids_device_create_instance();
287 
288     btstack_assert(num_reports > 0);
289     btstack_assert(report_storage != NULL);
290 
291     instance->hid_country_code    = hid_country_code;
292     instance->hid_descriptor      = hid_descriptor;
293     instance->hid_descriptor_size = hid_descriptor_size;
294 
295     // default
296     instance->hid_protocol_mode   = 1;
297 
298     // get service handle range
299     uint16_t start_handle = 0;
300     uint16_t end_handle   = 0xffff;
301     int service_found = gatt_server_get_handle_range_for_service_with_uuid16(ORG_BLUETOOTH_SERVICE_HUMAN_INTERFACE_DEVICE, &start_handle, &end_handle);
302     btstack_assert(service_found != 0);
303     UNUSED(service_found);
304 
305     // get report map handle
306     instance->hid_report_map_handle                               = gatt_server_get_value_handle_for_characteristic_with_uuid16(start_handle, end_handle, ORG_BLUETOOTH_CHARACTERISTIC_REPORT_MAP);
307 
308     // get report map handle
309     instance->hid_protocol_mode_value_handle                      = gatt_server_get_value_handle_for_characteristic_with_uuid16(start_handle, end_handle, ORG_BLUETOOTH_CHARACTERISTIC_PROTOCOL_MODE);
310 
311     // get value and client configuration handles for boot mouse input, boot keyboard input and report input
312     instance->hid_boot_mouse_input_value_handle                   = gatt_server_get_value_handle_for_characteristic_with_uuid16(start_handle, end_handle, ORG_BLUETOOTH_CHARACTERISTIC_BOOT_MOUSE_INPUT_REPORT);
313     instance->hid_boot_mouse_input_client_configuration_handle    = gatt_server_get_client_configuration_handle_for_characteristic_with_uuid16(start_handle, end_handle, ORG_BLUETOOTH_CHARACTERISTIC_BOOT_MOUSE_INPUT_REPORT);
314 
315     instance->hid_boot_keyboard_input_value_handle                = gatt_server_get_value_handle_for_characteristic_with_uuid16(start_handle, end_handle, ORG_BLUETOOTH_CHARACTERISTIC_BOOT_KEYBOARD_INPUT_REPORT);
316     instance->hid_boot_keyboard_input_client_configuration_handle = gatt_server_get_client_configuration_handle_for_characteristic_with_uuid16(start_handle, end_handle, ORG_BLUETOOTH_CHARACTERISTIC_BOOT_KEYBOARD_INPUT_REPORT);
317 
318     instance->hid_control_point_value_handle = gatt_server_get_value_handle_for_characteristic_with_uuid16(start_handle, end_handle, ORG_BLUETOOTH_CHARACTERISTIC_HID_CONTROL_POINT);
319 
320     log_info("hid_report_map_handle                               0x%02x", instance->hid_report_map_handle);
321     log_info("hid_protocol_mode_value_handle                      0x%02x", instance->hid_protocol_mode_value_handle);
322     log_info("hid_boot_mouse_input_value_handle                   0x%02x", instance->hid_boot_mouse_input_value_handle);
323     log_info("hid_boot_mouse_input_client_configuration_handle    0x%02x", instance->hid_boot_mouse_input_client_configuration_handle);
324     log_info("hid_boot_keyboard_input_value_handle                0x%02x", instance->hid_boot_keyboard_input_value_handle);
325     log_info("hid_boot_keyboard_input_client_configuration_handle 0x%02x", instance->hid_boot_keyboard_input_client_configuration_handle);
326     log_info("hid_control_point_value_handle                      0x%02x", instance->hid_control_point_value_handle);
327 
328     instance->hid_reports = report_storage;
329 
330     uint16_t hid_reports_num = num_reports;
331     uint16_t assigned_reports_num = 0;
332     uint16_t start_chr_handle = start_handle;
333 
334     while ( (start_chr_handle < end_handle) && (assigned_reports_num < hid_reports_num)) {
335         uint16_t chr_value_handle = gatt_server_get_value_handle_for_characteristic_with_uuid16(start_chr_handle, end_handle, ORG_BLUETOOTH_CHARACTERISTIC_REPORT);
336         if (chr_value_handle == 0){
337             break;
338         }
339 
340         uint16_t chr_client_configuration_handle = gatt_server_get_client_configuration_handle_for_characteristic_with_uuid16(start_chr_handle, end_handle, ORG_BLUETOOTH_CHARACTERISTIC_REPORT);
341         uint16_t report_reference_handle = gatt_server_get_descriptor_handle_for_characteristic_with_uuid16(start_chr_handle, end_handle, ORG_BLUETOOTH_CHARACTERISTIC_REPORT, ORG_BLUETOOTH_DESCRIPTOR_REPORT_REFERENCE);
342         uint16_t report_reference_value_len;
343         const uint8_t * report_reference_value = gatt_server_get_const_value_for_handle(report_reference_handle, &report_reference_value_len);
344 
345         if (report_reference_value == NULL){
346             break;
347         }
348         if (report_reference_value_len != 2){
349             break;
350         }
351 
352         hids_device_report_t * report = &hid_reports_storage[assigned_reports_num];
353         report->value_handle = chr_value_handle;
354         report->client_configuration_handle = chr_client_configuration_handle;
355         report->client_configuration_value = 0;
356 
357         report->id = report_reference_value[0];
358         report->type = (hid_report_type_t)report_reference_value[1];
359 
360         switch (report->type){
361             case HID_REPORT_TYPE_INPUT:
362                 instance->hid_input_reports_num++;
363                 break;
364             case HID_REPORT_TYPE_OUTPUT:
365                 instance->hid_output_reports_num++;
366                 break;
367             case HID_REPORT_TYPE_FEATURE:
368                 instance->hid_feature_reports_num++;
369                 break;
370             default:
371                 btstack_unreachable();
372                 return;
373         }
374         log_info("hid_report_value_handle                       0x%02x, id %u, type %u", report->value_handle, report->id, (uint8_t)report->type);
375         log_info("hid_report_client_configuration_handle        0x%02x", report->client_configuration_handle);
376 
377         assigned_reports_num++;
378         start_chr_handle = chr_client_configuration_handle + 1;
379     }
380 
381     // register service with ATT Server
382     hid_service.start_handle   = start_handle;
383     hid_service.end_handle     = end_handle;
384     hid_service.read_callback  = &att_read_callback;
385     hid_service.write_callback = &att_write_callback;
386     att_server_register_service_handler(&hid_service);
387 }
388 
389 /**
390  * @brief Set up HIDS Device
391  */
392 void hids_device_init(uint8_t country_code, const uint8_t * descriptor, uint16_t descriptor_size){
393     uint16_t hid_reports_num = sizeof(hid_reports_storage)/sizeof(hids_device_report_t);
394     hids_device_init_with_storage(country_code, descriptor, descriptor_size, hid_reports_num, &hid_reports_storage[0]);
395 }
396 
397 /**
398  * @brief Register callback for the HIDS Device client.
399  * @param callback
400  */
401 void hids_device_register_packet_handler(btstack_packet_handler_t callback){
402     packet_handler = callback;
403 }
404 
405 /**
406  * @brief Request can send now event to send HID Report
407  * Generates an HIDS_SUBEVENT_CAN_SEND_NOW subevent
408  * @param hid_cid
409  */
410 void hids_device_request_can_send_now_event(hci_con_handle_t con_handle){
411     hids_device_t * instance = hids_device_get_instance_for_con_handle(con_handle);
412     if (!instance){
413         log_error("no instance for handle 0x%02x", con_handle);
414         return;
415     }
416 
417     instance->battery_callback.callback = &hids_device_can_send_now;
418     instance->battery_callback.context  = (void*) (uintptr_t) con_handle;
419     att_server_register_can_send_now_callback(&instance->battery_callback, con_handle);
420 }
421 
422 /**
423  * @brief Send HID Report: Input
424  */
425 
426 uint8_t hids_device_send_report_with_id(hci_con_handle_t con_handle, uint16_t report_id, const uint8_t * report, uint16_t report_len){
427     hids_device_t * instance = hids_device_get_instance_for_con_handle(con_handle);
428     if (!instance){
429         log_error("no instance for handle 0x%02x", con_handle);
430         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
431     }
432 
433     hids_device_report_t * report_storage = hids_device_get_report_for_id(instance, report_id);
434     if (report_storage == NULL){
435         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
436     }
437 
438     return att_server_notify(con_handle, report_storage->value_handle, report, report_len);
439 }
440 
441 static uint8_t hids_device_send_report_with_type(hci_con_handle_t con_handle, const uint8_t * report, uint16_t report_len, hid_report_type_t report_type){
442     hids_device_t * instance = hids_device_get_instance_for_con_handle(con_handle);
443     if (!instance){
444         log_error("no instance for handle 0x%02x", con_handle);
445         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
446     }
447 
448     uint8_t pos = 0;
449     while (pos < (instance->hid_input_reports_num + instance->hid_output_reports_num + instance->hid_feature_reports_num)){
450         hids_device_report_t * report_storage = &instance->hid_reports[pos];
451 
452         if (report_storage->type == report_type){
453             return att_server_notify(con_handle, report_storage->value_handle, report, report_len);
454         }
455     }
456     return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
457 }
458 
459 void hids_device_send_input_report(hci_con_handle_t con_handle, const uint8_t * report, uint16_t report_len){
460     (void)hids_device_send_report_with_type(con_handle, report, report_len, HID_REPORT_TYPE_INPUT);
461 }
462 
463 /**
464  * @brief Send HID Report: Output
465  */
466 void hids_device_send_output_report(hci_con_handle_t con_handle, const uint8_t * report, uint16_t report_len){
467     (void)hids_device_send_report_with_type(con_handle, report, report_len, HID_REPORT_TYPE_OUTPUT);
468 }
469 
470 /**
471  * @brief Send HID Report: Feature
472  */
473 void hids_device_send_feature_report(hci_con_handle_t con_handle, const uint8_t * report, uint16_t report_len){
474     (void)hids_device_send_report_with_type(con_handle, report, report_len, HID_REPORT_TYPE_FEATURE);
475 }
476 
477 /**
478  * @brief Send HID Boot Mouse Input Report
479  */
480 void hids_device_send_boot_mouse_input_report(hci_con_handle_t con_handle, const uint8_t * report, uint16_t report_len){
481     hids_device_t * instance = hids_device_get_instance_for_con_handle(con_handle);
482     if (!instance){
483         log_error("no instance for handle 0x%02x", con_handle);
484         return;
485     }
486     att_server_notify(con_handle, instance->hid_boot_mouse_input_value_handle, report, report_len);
487 }
488 
489 /**
490  * @brief Send HID Boot Mouse Input Report
491  */
492 void hids_device_send_boot_keyboard_input_report(hci_con_handle_t con_handle, const uint8_t * report, uint16_t report_len){
493     hids_device_t * instance = hids_device_get_instance_for_con_handle(con_handle);
494     if (!instance){
495         log_error("no instance for handle 0x%02x", con_handle);
496         return;
497     }
498     att_server_notify(con_handle, instance->hid_boot_keyboard_input_value_handle, report, report_len);
499 }
500