xref: /btstack/src/ble/gatt-service/tx_power_service_server.c (revision 08a78038ba366a6a2a2df8fea05d5123880fdff2)
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__ "tx_power_service_server.c"
39 
40 
41 /**
42  * Implementation of the GATT TX Power Service Server
43  * To use with your application, add '#import <tx_power_service.gatt' to your .gatt file
44  */
45 
46 #include "btstack_defines.h"
47 #include "ble/att_db.h"
48 #include "ble/att_server.h"
49 #include "btstack_util.h"
50 #include "bluetooth_gatt.h"
51 #include "btstack_debug.h"
52 
53 
54 #include "ble/gatt-service/tx_power_service_server.h"
55 
56 static btstack_context_callback_registration_t tx_power_level_callback;
57 static att_service_handler_t       tx_power_service_handler;
58 
59 static int8_t 	tx_power_level_value;
60 static uint16_t tx_power_level_value_handle;
61 
62 static uint16_t tx_power_level_client_configuration;
63 static uint16_t tx_power_level_client_configuration_handle;
64 static hci_con_handle_t tx_power_level_client_configuration_con_handle;
65 
66 static uint16_t tx_power_service_read_callback(hci_con_handle_t con_handle, uint16_t attribute_handle, uint16_t offset, uint8_t * buffer, uint16_t buffer_size){
67 	UNUSED(con_handle);
68 
69 	if (attribute_handle == tx_power_level_value_handle){
70 		return att_read_callback_handle_byte((uint8_t)tx_power_level_value, offset, buffer, buffer_size);
71 	}
72     if (attribute_handle == tx_power_level_client_configuration_handle){
73         return att_read_callback_handle_little_endian_16(tx_power_level_client_configuration, offset, buffer, buffer_size);
74     }
75 	return 0;
76 }
77 
78 
79 static int tx_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){
80     UNUSED(offset);
81     UNUSED(buffer_size);
82     UNUSED(con_handle);
83 
84     if (transaction_mode != ATT_TRANSACTION_MODE_NONE){
85         return 0;
86     }
87 
88     if (attribute_handle == tx_power_level_client_configuration_handle){
89         tx_power_level_client_configuration = little_endian_read_16(buffer, 0);
90         tx_power_level_client_configuration_con_handle = con_handle;
91     }
92     return 0;
93 }
94 
95 
96 void tx_power_service_server_init(int8_t tx_power_level_dBm){
97 	tx_power_level_value = tx_power_level_dBm;
98 
99 	// get service handle range
100 	uint16_t start_handle = 0;
101 	uint16_t end_handle   = 0xffff;
102 	bool service_found = gatt_server_get_handle_range_for_service_with_uuid16(ORG_BLUETOOTH_SERVICE_TX_POWER, &start_handle, &end_handle);
103 	btstack_assert(service_found);
104 	UNUSED(service_found);
105 
106 	// get characteristic value handle and client configuration handle
107 	tx_power_level_value_handle = gatt_server_get_value_handle_for_characteristic_with_uuid16(start_handle, end_handle, ORG_BLUETOOTH_CHARACTERISTIC_TX_POWER_LEVEL);
108     tx_power_level_client_configuration_handle = gatt_server_get_client_configuration_handle_for_characteristic_with_uuid16(start_handle, end_handle, ORG_BLUETOOTH_CHARACTERISTIC_TX_POWER_LEVEL);
109 
110 	// register service with ATT Server
111 	tx_power_service_handler.start_handle   = start_handle;
112 	tx_power_service_handler.end_handle     = end_handle;
113 	tx_power_service_handler.read_callback  = &tx_power_service_read_callback;
114 	tx_power_service_handler.write_callback = &tx_power_service_write_callback;
115 	att_server_register_service_handler(&tx_power_service_handler);
116 }
117 
118 static void tx_power_service_can_send_now(void * context){
119     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) context;
120     uint8_t value = (uint8_t)tx_power_level_value;
121     att_server_notify(con_handle, tx_power_level_value_handle, &value, 1);
122 }
123 
124 void tx_power_service_server_set_level(int8_t tx_power_level_dBm){
125 	tx_power_level_value = tx_power_level_dBm;
126     if (tx_power_level_client_configuration != 0){
127         tx_power_level_callback.callback = &tx_power_service_can_send_now;
128         tx_power_level_callback.context  = (void*) (uintptr_t) tx_power_level_client_configuration_con_handle;
129         att_server_register_can_send_now_callback(&tx_power_level_callback, tx_power_level_client_configuration_con_handle);
130     }
131 }
132