zephyr/subsys/bluetooth/services/bas.c

99 lines
2.2 KiB
C

/** @file
* @brief GATT Battery Service
*/
/*
* Copyright (c) 2018 Nordic Semiconductor ASA
* Copyright (c) 2016 Intel Corporation
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <errno.h>
#include <zephyr/init.h>
#include <zephyr/sys/__assert.h>
#include <stdbool.h>
#include <zephyr/types.h>
#include <zephyr/bluetooth/bluetooth.h>
#include <zephyr/bluetooth/conn.h>
#include <zephyr/bluetooth/gatt.h>
#include <zephyr/bluetooth/uuid.h>
#include <zephyr/bluetooth/services/bas.h>
#define LOG_LEVEL CONFIG_BT_BAS_LOG_LEVEL
#include <zephyr/logging/log.h>
LOG_MODULE_REGISTER(bas);
static uint8_t battery_level = 100U;
static void blvl_ccc_cfg_changed(const struct bt_gatt_attr *attr,
uint16_t value)
{
ARG_UNUSED(attr);
bool notif_enabled = (value == BT_GATT_CCC_NOTIFY);
LOG_INF("BAS Notifications %s", notif_enabled ? "enabled" : "disabled");
}
static ssize_t read_blvl(struct bt_conn *conn,
const struct bt_gatt_attr *attr, void *buf,
uint16_t len, uint16_t offset)
{
uint8_t lvl8 = battery_level;
return bt_gatt_attr_read(conn, attr, buf, len, offset, &lvl8,
sizeof(lvl8));
}
/* Constant values from the Assigned Numbers specification:
* https://www.bluetooth.com/wp-content/uploads/Files/Specification/Assigned_Numbers.pdf?id=89
*/
static const struct bt_gatt_cpf level_cpf = {
.format = 0x04, /* uint8 */
.exponent = 0x0,
.unit = 0x27AD, /* Percentage */
.name_space = 0x01, /* Bluetooth SIG */
.description = 0x0106, /* "main" */
};
BT_GATT_SERVICE_DEFINE(bas,
BT_GATT_PRIMARY_SERVICE(BT_UUID_BAS),
BT_GATT_CHARACTERISTIC(BT_UUID_BAS_BATTERY_LEVEL,
BT_GATT_CHRC_READ | BT_GATT_CHRC_NOTIFY,
BT_GATT_PERM_READ, read_blvl, NULL,
&battery_level),
BT_GATT_CCC(blvl_ccc_cfg_changed,
BT_GATT_PERM_READ | BT_GATT_PERM_WRITE),
BT_GATT_CPF(&level_cpf),
);
static int bas_init(void)
{
return 0;
}
uint8_t bt_bas_get_battery_level(void)
{
return battery_level;
}
int bt_bas_set_battery_level(uint8_t level)
{
int rc;
if (level > 100U) {
return -EINVAL;
}
battery_level = level;
rc = bt_gatt_notify(NULL, &bas.attrs[1], &level, sizeof(level));
return rc == -ENOTCONN ? 0 : rc;
}
SYS_INIT(bas_init, APPLICATION, CONFIG_APPLICATION_INIT_PRIORITY);