Oscar Ariza / nRF51822

nordic

Fork of nRF51822 by Nordic Semiconductor

btle/custom/custom_helper.cpp@66:b3680699d9a4, 2014-09-22 (annotated)

Committer:
Rohit Grover
Date:
Mon Sep 22 11:19:51 2014 +0100
Revision:
66:b3680699d9a4
Parent:
59:2819e564b613
Child:
82:6c51cbe4bc12
Release 0.2.0

=============



Highlights:

  Add support for over-the-air firmware updates.



Features

~~~~~~~~



- Add files to support DFU bootloader.



- charHandle is now a part of GattCharacteristicWriteCBParams.



- nRF51GattServer::addService(): Skip any incompletely defined, read-only

  characteristics. For instance, the DeviceInformationService may have many

  optional, read-only characteristics which may be safely dropped if the

  application hasn't defined them.



Bugfixes

~~~~~~~~



None.



Compatibility

~~~~~~~~~~~~~



Works with 0.2.0 of BLE_API.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Rohit Grover 22:c6ee8136847e 1 /* mbed Microcontroller Library
Rohit Grover 22:c6ee8136847e 2 * Copyright (c) 2006-2013 ARM Limited
Rohit Grover 22:c6ee8136847e 3 *
Rohit Grover 22:c6ee8136847e 4 * Licensed under the Apache License, Version 2.0 (the "License");
Rohit Grover 22:c6ee8136847e 5 * you may not use this file except in compliance with the License.
Rohit Grover 22:c6ee8136847e 6 * You may obtain a copy of the License at
Rohit Grover 22:c6ee8136847e 7 *
Rohit Grover 22:c6ee8136847e 8 * http://www.apache.org/licenses/LICENSE-2.0
Rohit Grover 22:c6ee8136847e 9 *
Rohit Grover 22:c6ee8136847e 10 * Unless required by applicable law or agreed to in writing, software
Rohit Grover 22:c6ee8136847e 11 * distributed under the License is distributed on an "AS IS" BASIS,
Rohit Grover 22:c6ee8136847e 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
Rohit Grover 22:c6ee8136847e 13 * See the License for the specific language governing permissions and
Rohit Grover 22:c6ee8136847e 14 * limitations under the License.
Rohit Grover 22:c6ee8136847e 15 */
Rohit Grover 22:c6ee8136847e 16
Rohit Grover 22:c6ee8136847e 17 #include "custom_helper.h"
Rohit Grover 22:c6ee8136847e 18
Rohit Grover 22:c6ee8136847e 19 /*
Rohit Grover 22:c6ee8136847e 20 * The current version of the soft-device doesn't handle duplicate 128-bit UUIDs
Rohit Grover 22:c6ee8136847e 21 * very well. It is therefore necessary to filter away duplicates before
Rohit Grover 22:c6ee8136847e 22 * passing long UUIDs to sd_ble_uuid_vs_add(). The following types and data
Rohit Grover 22:c6ee8136847e 23 * structures involved in maintaining a local cache of 128-bit UUIDs.
Rohit Grover 22:c6ee8136847e 24 */
Rohit Grover 22:c6ee8136847e 25 typedef struct {
Rohit Grover 56:a1071b629aa3 26 LongUUIDBytes_t uuid;
Rohit Grover 56:a1071b629aa3 27 uint8_t type;
Rohit Grover 22:c6ee8136847e 28 } converted_uuid_table_entry_t;
Rohit Grover 66:b3680699d9a4 29 static const unsigned UUID_TABLE_MAX_ENTRIES = 8; /* This is the maximum number of 128-bit UUIDs with distinct bases that
Rohit Grover 66:b3680699d9a4 30 * we expect to be in use; increase this limit if needed. */
Rohit Grover 22:c6ee8136847e 31 static unsigned uuidTableEntries = 0; /* current usage of the table */
Rohit Grover 22:c6ee8136847e 32 converted_uuid_table_entry_t convertedUUIDTable[UUID_TABLE_MAX_ENTRIES];
Rohit Grover 22:c6ee8136847e 33
Rohit Grover 22:c6ee8136847e 34 /**
Rohit Grover 22:c6ee8136847e 35 * lookup the cache of previously converted 128-bit UUIDs to find a type value.
Rohit Grover 66:b3680699d9a4 36 * @param uuid base 128-bit UUID
Rohit Grover 22:c6ee8136847e 37 * @param recoveredType the type field of the 3-byte nRF's uuid.
Rohit Grover 22:c6ee8136847e 38 * @return true if a match is found.
Rohit Grover 22:c6ee8136847e 39 */
Rohit Grover 22:c6ee8136847e 40 static bool
Rohit Grover 56:a1071b629aa3 41 lookupConvertedUUIDTable(const LongUUIDBytes_t uuid, uint8_t *recoveredType)
Rohit Grover 22:c6ee8136847e 42 {
Rohit Grover 22:c6ee8136847e 43 unsigned i;
Rohit Grover 22:c6ee8136847e 44 for (i = 0; i < uuidTableEntries; i++) {
Rohit Grover 66:b3680699d9a4 45 if (memcmp(convertedUUIDTable[i].uuid, uuid, LENGTH_OF_LONG_UUID) == 0) {
Rohit Grover 22:c6ee8136847e 46 *recoveredType = convertedUUIDTable[i].type;
Rohit Grover 22:c6ee8136847e 47 return true;
Rohit Grover 22:c6ee8136847e 48 }
Rohit Grover 22:c6ee8136847e 49 }
Rohit Grover 22:c6ee8136847e 50
Rohit Grover 22:c6ee8136847e 51 return false;
Rohit Grover 22:c6ee8136847e 52 }
Rohit Grover 22:c6ee8136847e 53
Rohit Grover 22:c6ee8136847e 54 static void
Rohit Grover 56:a1071b629aa3 55 addToConvertedUUIDTable(const LongUUIDBytes_t uuid, uint8_t type)
Rohit Grover 22:c6ee8136847e 56 {
Rohit Grover 22:c6ee8136847e 57 if (uuidTableEntries == UUID_TABLE_MAX_ENTRIES) {
Rohit Grover 66:b3680699d9a4 58 return; /* recovery needed; or at least the user should be warned about this fact.*/
Rohit Grover 22:c6ee8136847e 59 }
Rohit Grover 22:c6ee8136847e 60
Rohit Grover 22:c6ee8136847e 61 memcpy(convertedUUIDTable[uuidTableEntries].uuid, uuid,LENGTH_OF_LONG_UUID);
Rohit Grover 22:c6ee8136847e 62 convertedUUIDTable[uuidTableEntries].type = type;
Rohit Grover 22:c6ee8136847e 63 uuidTableEntries++;
Rohit Grover 22:c6ee8136847e 64 }
Rohit Grover 22:c6ee8136847e 65
Rohit Grover 22:c6ee8136847e 66 /**
Rohit Grover 22:c6ee8136847e 67 * The nRF transport has its own 3-byte representation of a UUID. If the user-
Rohit Grover 22:c6ee8136847e 68 * specified UUID is 128-bits wide, then the UUID base needs to be added to the
Rohit Grover 22:c6ee8136847e 69 * soft-device and converted to a 3-byte handle before being used further. This
Rohit Grover 22:c6ee8136847e 70 * function is responsible for this translation of user-specified UUIDs into
Rohit Grover 22:c6ee8136847e 71 * nRF's representation.
Rohit Grover 22:c6ee8136847e 72 *
Rohit Grover 22:c6ee8136847e 73 * @param[in] uuid
Rohit Grover 22:c6ee8136847e 74 * user-specified UUID
Rohit Grover 22:c6ee8136847e 75 * @return nRF
Rohit Grover 22:c6ee8136847e 76 * 3-byte UUID (containing a type and 16-bit UUID) representation
Rohit Grover 22:c6ee8136847e 77 * to be used with SVC calls.
Rohit Grover 22:c6ee8136847e 78 */
Rohit Grover 22:c6ee8136847e 79 ble_uuid_t custom_convert_to_nordic_uuid(const UUID &uuid)
Rohit Grover 22:c6ee8136847e 80 {
Rohit Grover 22:c6ee8136847e 81 ble_uuid_t nordicUUID = {
Rohit Grover 22:c6ee8136847e 82 .uuid = uuid.getShortUUID(),
Rohit Grover 22:c6ee8136847e 83 .type = BLE_UUID_TYPE_UNKNOWN /* to be set below */
Rohit Grover 22:c6ee8136847e 84 };
Rohit Grover 22:c6ee8136847e 85
Rohit Grover 22:c6ee8136847e 86 if (uuid.shortOrLong() == UUID::UUID_TYPE_SHORT) {
Rohit Grover 22:c6ee8136847e 87 nordicUUID.type = BLE_UUID_TYPE_BLE;
Rohit Grover 22:c6ee8136847e 88 } else {
Rohit Grover 22:c6ee8136847e 89 if (!lookupConvertedUUIDTable(uuid.getBaseUUID(), &nordicUUID.type)) {
Rohit Grover 22:c6ee8136847e 90 nordicUUID.type = custom_add_uuid_base(uuid.getBaseUUID());
Rohit Grover 22:c6ee8136847e 91 addToConvertedUUIDTable(uuid.getBaseUUID(), nordicUUID.type);
Rohit Grover 22:c6ee8136847e 92 }
Rohit Grover 22:c6ee8136847e 93 }
Rohit Grover 22:c6ee8136847e 94
Rohit Grover 22:c6ee8136847e 95 return nordicUUID;
Rohit Grover 22:c6ee8136847e 96 }
Rohit Grover 22:c6ee8136847e 97
Rohit Grover 22:c6ee8136847e 98 /**************************************************************************/
Rohit Grover 22:c6ee8136847e 99 /*!
Rohit Grover 22:c6ee8136847e 100 @brief Adds the base UUID to the custom service. All UUIDs used
Rohit Grover 22:c6ee8136847e 101 by this service are based on this 128-bit UUID.
Rohit Grover 22:c6ee8136847e 102
Rohit Grover 22:c6ee8136847e 103 @note This UUID needs to be added to the SoftDevice stack before
Rohit Grover 22:c6ee8136847e 104 adding the service's primary service via
Rohit Grover 22:c6ee8136847e 105 'sd_ble_gatts_service_add'
Rohit Grover 22:c6ee8136847e 106
Rohit Grover 22:c6ee8136847e 107 @param[in] p_uuid_base A pointer to the 128-bit UUID array (8*16)
Rohit Grover 22:c6ee8136847e 108
Rohit Grover 22:c6ee8136847e 109 @returns The UUID type.
Rohit Grover 22:c6ee8136847e 110 A return value of 0 should be considered an error.
Rohit Grover 22:c6ee8136847e 111
Rohit Grover 22:c6ee8136847e 112 @retval 0x00 BLE_UUID_TYPE_UNKNOWN
Rohit Grover 22:c6ee8136847e 113 @retval 0x01 BLE_UUID_TYPE_BLE
Rohit Grover 22:c6ee8136847e 114 @retval 0x02 BLE_UUID_TYPE_VENDOR_BEGIN
Rohit Grover 22:c6ee8136847e 115
Rohit Grover 22:c6ee8136847e 116 @section EXAMPLE
Rohit Grover 22:c6ee8136847e 117 @code
Rohit Grover 22:c6ee8136847e 118
Rohit Grover 22:c6ee8136847e 119 // Take note that bytes 2/3 are blank since these are used to identify
Rohit Grover 22:c6ee8136847e 120 // the primary service and individual characteristics
Rohit Grover 22:c6ee8136847e 121 #define CFG_CUSTOM_UUID_BASE "\x6E\x40\x00\x00\xB5\xA3\xF3\x93\xE0\xA9\xE5\x0E\x24\xDC\xCA\x9E"
Rohit Grover 22:c6ee8136847e 122
Rohit Grover 22:c6ee8136847e 123 uint8_t uuid_type = custom_add_uuid_base(CFG_CUSTOM_UUID_BASE);
Rohit Grover 22:c6ee8136847e 124 ASSERT(uuid_type > 0, ERROR_NOT_FOUND);
Rohit Grover 22:c6ee8136847e 125
Rohit Grover 22:c6ee8136847e 126 // We can now safely add the primary service and any characteristics
Rohit Grover 22:c6ee8136847e 127 // for our custom service ...
Rohit Grover 22:c6ee8136847e 128
Rohit Grover 22:c6ee8136847e 129 @endcode
Rohit Grover 22:c6ee8136847e 130 */
Rohit Grover 22:c6ee8136847e 131 /**************************************************************************/
Rohit Grover 22:c6ee8136847e 132 uint8_t custom_add_uuid_base(uint8_t const *const p_uuid_base)
Rohit Grover 22:c6ee8136847e 133 {
Rohit Grover 22:c6ee8136847e 134 ble_uuid128_t base_uuid;
Rohit Grover 22:c6ee8136847e 135 uint8_t uuid_type = 0;
Rohit Grover 22:c6ee8136847e 136
Rohit Grover 22:c6ee8136847e 137 /* Reverse the bytes since ble_uuid128_t is LSB */
Rohit Grover 22:c6ee8136847e 138 for (uint8_t i = 0; i<16; i++) {
Rohit Grover 22:c6ee8136847e 139 base_uuid.uuid128[i] = p_uuid_base[15 - i];
Rohit Grover 22:c6ee8136847e 140 }
Rohit Grover 22:c6ee8136847e 141
Rohit Grover 22:c6ee8136847e 142 ASSERT_INT( ERROR_NONE, sd_ble_uuid_vs_add( &base_uuid, &uuid_type ), 0);
Rohit Grover 22:c6ee8136847e 143
Rohit Grover 22:c6ee8136847e 144 return uuid_type;
Rohit Grover 22:c6ee8136847e 145 }
Rohit Grover 22:c6ee8136847e 146
Rohit Grover 22:c6ee8136847e 147 /**************************************************************************/
Rohit Grover 22:c6ee8136847e 148 /*!
Rohit Grover 22:c6ee8136847e 149
Rohit Grover 22:c6ee8136847e 150 */
Rohit Grover 22:c6ee8136847e 151 /**************************************************************************/
Rohit Grover 22:c6ee8136847e 152 error_t custom_decode_uuid_base(uint8_t const *const p_uuid_base,
Rohit Grover 22:c6ee8136847e 153 ble_uuid_t *p_uuid)
Rohit Grover 22:c6ee8136847e 154 {
Rohit Grover 56:a1071b629aa3 155 LongUUIDBytes_t uuid_base_le;
Rohit Grover 22:c6ee8136847e 156
Rohit Grover 22:c6ee8136847e 157 /* Reverse the bytes since ble_uuid128_t is LSB */
Rohit Grover 22:c6ee8136847e 158 for (uint8_t i = 0; i<16; i++) {
Rohit Grover 22:c6ee8136847e 159 uuid_base_le[i] = p_uuid_base[15 - i];
Rohit Grover 22:c6ee8136847e 160 }
Rohit Grover 22:c6ee8136847e 161
Rohit Grover 22:c6ee8136847e 162 ASSERT_STATUS( sd_ble_uuid_decode(16, uuid_base_le, p_uuid));
Rohit Grover 22:c6ee8136847e 163
Rohit Grover 22:c6ee8136847e 164 return ERROR_NONE;
Rohit Grover 22:c6ee8136847e 165 }
Rohit Grover 22:c6ee8136847e 166
Rohit Grover 22:c6ee8136847e 167 /**************************************************************************/
Rohit Grover 22:c6ee8136847e 168 /*!
Rohit Grover 22:c6ee8136847e 169 @brief Adds a new characteristic to the custom service, assigning
Rohit Grover 22:c6ee8136847e 170 properties, a UUID add-on value, etc.
Rohit Grover 22:c6ee8136847e 171
Rohit Grover 22:c6ee8136847e 172 @param[in] service_handle
Rohit Grover 22:c6ee8136847e 173 @param[in] p_uuid The 16-bit value to add to the base UUID
Rohit Grover 22:c6ee8136847e 174 for this characteristic (normally >1
Rohit Grover 22:c6ee8136847e 175 since 1 is typically used by the primary
Rohit Grover 22:c6ee8136847e 176 service).
Rohit Grover 22:c6ee8136847e 177 @param[in] char_props The characteristic properties, as
Rohit Grover 22:c6ee8136847e 178 defined by ble_gatt_char_props_t
Rohit Grover 22:c6ee8136847e 179 @param[in] max_length The maximum length of this characeristic
Rohit Grover 22:c6ee8136847e 180 @param[in] p_char_handle
Rohit Grover 22:c6ee8136847e 181
Rohit Grover 22:c6ee8136847e 182 @returns
Rohit Grover 22:c6ee8136847e 183 @retval ERROR_NONE Everything executed normally
Rohit Grover 22:c6ee8136847e 184 */
Rohit Grover 22:c6ee8136847e 185 /**************************************************************************/
Rohit Grover 22:c6ee8136847e 186 error_t custom_add_in_characteristic(uint16_t service_handle,
Rohit Grover 22:c6ee8136847e 187 ble_uuid_t *p_uuid,
Rohit Grover 22:c6ee8136847e 188 uint8_t properties,
Rohit Grover 22:c6ee8136847e 189 uint8_t *p_data,
Rohit Grover 22:c6ee8136847e 190 uint16_t min_length,
Rohit Grover 22:c6ee8136847e 191 uint16_t max_length,
Rohit Grover 22:c6ee8136847e 192 ble_gatts_char_handles_t *p_char_handle)
Rohit Grover 22:c6ee8136847e 193 {
Rohit Grover 22:c6ee8136847e 194 /* Characteristic metadata */
Rohit Grover 22:c6ee8136847e 195 ble_gatts_attr_md_t cccd_md;
Rohit Grover 22:c6ee8136847e 196 ble_gatt_char_props_t char_props;
Rohit Grover 22:c6ee8136847e 197
Rohit Grover 22:c6ee8136847e 198 memcpy(&char_props, &properties, 1);
Rohit Grover 22:c6ee8136847e 199
Rohit Grover 22:c6ee8136847e 200 if (char_props.notify || char_props.indicate) {
Rohit Grover 22:c6ee8136847e 201 /* Notification requires cccd */
Rohit Grover 22:c6ee8136847e 202 memclr_( &cccd_md, sizeof(ble_gatts_attr_md_t));
Rohit Grover 22:c6ee8136847e 203 cccd_md.vloc = BLE_GATTS_VLOC_STACK;
Rohit Grover 22:c6ee8136847e 204 BLE_GAP_CONN_SEC_MODE_SET_OPEN(&cccd_md.read_perm);
Rohit Grover 22:c6ee8136847e 205 BLE_GAP_CONN_SEC_MODE_SET_OPEN(&cccd_md.write_perm);
Rohit Grover 22:c6ee8136847e 206 }
Rohit Grover 22:c6ee8136847e 207
Rohit Grover 22:c6ee8136847e 208 ble_gatts_char_md_t char_md = {0};
Rohit Grover 22:c6ee8136847e 209
Rohit Grover 22:c6ee8136847e 210 char_md.char_props = char_props;
Rohit Grover 22:c6ee8136847e 211 char_md.p_cccd_md =
Rohit Grover 22:c6ee8136847e 212 (char_props.notify || char_props.indicate) ? &cccd_md : NULL;
Rohit Grover 22:c6ee8136847e 213
Rohit Grover 22:c6ee8136847e 214 /* Attribute declaration */
Rohit Grover 22:c6ee8136847e 215 ble_gatts_attr_md_t attr_md = {0};
Rohit Grover 22:c6ee8136847e 216
Rohit Grover 22:c6ee8136847e 217 attr_md.vloc = BLE_GATTS_VLOC_STACK;
Rohit Grover 22:c6ee8136847e 218 attr_md.vlen = (min_length == max_length) ? 0 : 1;
Rohit Grover 22:c6ee8136847e 219
Rohit Grover 22:c6ee8136847e 220 if (char_props.read || char_props.notify || char_props.indicate) {
Rohit Grover 22:c6ee8136847e 221 BLE_GAP_CONN_SEC_MODE_SET_OPEN(&attr_md.read_perm);
Rohit Grover 22:c6ee8136847e 222 }
Rohit Grover 22:c6ee8136847e 223
Rohit Grover 22:c6ee8136847e 224 if (char_props.write) {
Rohit Grover 22:c6ee8136847e 225 BLE_GAP_CONN_SEC_MODE_SET_OPEN(&attr_md.write_perm);
Rohit Grover 22:c6ee8136847e 226 }
Rohit Grover 22:c6ee8136847e 227
Rohit Grover 22:c6ee8136847e 228 ble_gatts_attr_t attr_char_value = {0};
Rohit Grover 22:c6ee8136847e 229
Rohit Grover 22:c6ee8136847e 230 attr_char_value.p_uuid = p_uuid;
Rohit Grover 22:c6ee8136847e 231 attr_char_value.p_attr_md = &attr_md;
Rohit Grover 22:c6ee8136847e 232 attr_char_value.init_len = min_length;
Rohit Grover 22:c6ee8136847e 233 attr_char_value.max_len = max_length;
Rohit Grover 22:c6ee8136847e 234 attr_char_value.p_value = p_data;
Rohit Grover 22:c6ee8136847e 235
Rohit Grover 22:c6ee8136847e 236 ASSERT_STATUS ( sd_ble_gatts_characteristic_add(service_handle,
Rohit Grover 22:c6ee8136847e 237 &char_md,
Rohit Grover 22:c6ee8136847e 238 &attr_char_value,
Rohit Grover 22:c6ee8136847e 239 p_char_handle));
Rohit Grover 22:c6ee8136847e 240
Rohit Grover 22:c6ee8136847e 241 return ERROR_NONE;
Rohit Grover 22:c6ee8136847e 242 }
Rohit Grover 59:2819e564b613 243
Rohit Grover 59:2819e564b613 244
Rohit Grover 59:2819e564b613 245
Rohit Grover 59:2819e564b613 246 /**************************************************************************/
Rohit Grover 59:2819e564b613 247 /*!
Rohit Grover 59:2819e564b613 248 @brief Adds a new descriptor to the custom service, assigning
Rohit Grover 59:2819e564b613 249 value, a UUID add-on value, etc.
Rohit Grover 59:2819e564b613 250
Rohit Grover 59:2819e564b613 251 @param[in] char_handle
Rohit Grover 59:2819e564b613 252 @param[in] p_uuid The 16-bit value to add to the base UUID
Rohit Grover 59:2819e564b613 253 for this descriptor (normally >1
Rohit Grover 59:2819e564b613 254 since 1 is typically used by the primary
Rohit Grover 59:2819e564b613 255 service).
Rohit Grover 59:2819e564b613 256 @param[in] max_length The maximum length of this descriptor
Rohit Grover 59:2819e564b613 257
Rohit Grover 59:2819e564b613 258 @returns
Rohit Grover 59:2819e564b613 259 @retval ERROR_NONE Everything executed normally
Rohit Grover 59:2819e564b613 260 */
Rohit Grover 59:2819e564b613 261 /**************************************************************************/
Rohit Grover 59:2819e564b613 262 error_t custom_add_in_descriptor(uint16_t char_handle,
Rohit Grover 59:2819e564b613 263 ble_uuid_t *p_uuid,
Rohit Grover 59:2819e564b613 264 uint8_t *p_data,
Rohit Grover 59:2819e564b613 265 uint16_t min_length,
Rohit Grover 59:2819e564b613 266 uint16_t max_length,
Rohit Grover 59:2819e564b613 267 uint16_t *p_desc_handle)
Rohit Grover 59:2819e564b613 268 {
Rohit Grover 59:2819e564b613 269 /* Descriptor metadata */
Rohit Grover 59:2819e564b613 270 ble_gatts_attr_md_t desc_md = {0};
Rohit Grover 59:2819e564b613 271
Rohit Grover 59:2819e564b613 272 desc_md.vloc = BLE_GATTS_VLOC_STACK;
Rohit Grover 59:2819e564b613 273 desc_md.vlen = (min_length == max_length) ? 0 : 1;
Rohit Grover 59:2819e564b613 274
Rohit Grover 59:2819e564b613 275 /* Make it readable and writable */
Rohit Grover 59:2819e564b613 276 BLE_GAP_CONN_SEC_MODE_SET_OPEN(&desc_md.read_perm);
Rohit Grover 59:2819e564b613 277 BLE_GAP_CONN_SEC_MODE_SET_OPEN(&desc_md.write_perm);
Rohit Grover 59:2819e564b613 278
Rohit Grover 59:2819e564b613 279 ble_gatts_attr_t attr_desc = {0};
Rohit Grover 59:2819e564b613 280
Rohit Grover 59:2819e564b613 281 attr_desc.p_uuid = p_uuid;
Rohit Grover 59:2819e564b613 282 attr_desc.p_attr_md = &desc_md;
Rohit Grover 59:2819e564b613 283 attr_desc.init_len = min_length;
Rohit Grover 59:2819e564b613 284 attr_desc.max_len = max_length;
Rohit Grover 59:2819e564b613 285 attr_desc.p_value = p_data;
Rohit Grover 59:2819e564b613 286
Rohit Grover 59:2819e564b613 287 ASSERT_STATUS ( sd_ble_gatts_descriptor_add(char_handle,
Rohit Grover 59:2819e564b613 288 &attr_desc,
Rohit Grover 59:2819e564b613 289 p_desc_handle));
Rohit Grover 59:2819e564b613 290
Rohit Grover 59:2819e564b613 291 return ERROR_NONE;
Rohit Grover 59:2819e564b613 292 }