text: /** @file
   *  @brief HRS Service sample
   */
  
  /*
   * Copyright (c) 2016 Intel Corporation
   *
   * SPDX-License-Identifier: Apache-2.0
   */
  
  #include <zephyr/types.h>
  #include <stddef.h>
  #include <string.h>
  #include <errno.h>
  #include <zephyr.h>
  #include <init.h>
  
  #include <bluetooth/bluetooth.h>
  #include <bluetooth/hci.h>
  #include <bluetooth/conn.h>
  #include <bluetooth/uuid.h>
  #include <bluetooth/gatt.h>
  
  #define LOG_LEVEL CONFIG_BT_HRS_LOG_LEVEL
  #include <logging/log.h>
  LOG_MODULE_REGISTER(hrs);
  
  
  #define GATT_PERM_READ_MASK     (BT_GATT_PERM_READ | \
  				 BT_GATT_PERM_READ_ENCRYPT | \
  				 BT_GATT_PERM_READ_AUTHEN)
  #define GATT_PERM_WRITE_MASK    (BT_GATT_PERM_WRITE | \
  				 BT_GATT_PERM_WRITE_ENCRYPT | \
  				 BT_GATT_PERM_WRITE_AUTHEN)
  
  #ifndef CONFIG_BT_HRS_DEFAULT_PERM_RW_AUTHEN
  #define CONFIG_BT_HRS_DEFAULT_PERM_RW_AUTHEN 0
  #endif
  #ifndef CONFIG_BT_HRS_DEFAULT_PERM_RW_ENCRYPT
  #define CONFIG_BT_HRS_DEFAULT_PERM_RW_ENCRYPT 0
  #endif
  #ifndef CONFIG_BT_HRS_DEFAULT_PERM_RW
  #define CONFIG_BT_HRS_DEFAULT_PERM_RW 0
  #endif
  
  #define HRS_GATT_PERM_DEFAULT (						\
  	CONFIG_BT_HRS_DEFAULT_PERM_RW_AUTHEN ?				\
  	(BT_GATT_PERM_READ_AUTHEN | BT_GATT_PERM_WRITE_AUTHEN) :	\
  	CONFIG_BT_HRS_DEFAULT_PERM_RW_ENCRYPT ?				\
  	(BT_GATT_PERM_READ_ENCRYPT | BT_GATT_PERM_WRITE_ENCRYPT) :	\
  	(BT_GATT_PERM_READ | BT_GATT_PERM_WRITE))			\
  
  static uint8_t hrs_blsc;
  
  static void hrmc_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("HRS notifications %s", notif_enabled ? "enabled" : "disabled");
  }
  
  static ssize_t read_blsc(struct bt_conn *conn, const struct bt_gatt_attr *attr,
  			 void *buf, uint16_t len, uint16_t offset)
  {
  	return bt_gatt_attr_read(conn, attr, buf, len, offset, &hrs_blsc,
  				 sizeof(hrs_blsc));
  }
  
  /* Heart Rate Service Declaration */
  BT_GATT_SERVICE_DEFINE(hrs_svc,
  	BT_GATT_PRIMARY_SERVICE(BT_UUID_HRS),
  	BT_GATT_CHARACTERISTIC(BT_UUID_HRS_MEASUREMENT, BT_GATT_CHRC_NOTIFY,
  			       BT_GATT_PERM_NONE, NULL, NULL, NULL),
  	BT_GATT_CCC(hrmc_ccc_cfg_changed,
  		    HRS_GATT_PERM_DEFAULT),
  	BT_GATT_CHARACTERISTIC(BT_UUID_HRS_BODY_SENSOR, BT_GATT_CHRC_READ,
  			       HRS_GATT_PERM_DEFAULT & GATT_PERM_READ_MASK,
  			       read_blsc, NULL, NULL),
  	BT_GATT_CHARACTERISTIC(BT_UUID_HRS_CONTROL_POINT, BT_GATT_CHRC_WRITE,
  			       HRS_GATT_PERM_DEFAULT & GATT_PERM_WRITE_MASK,
  			       NULL, NULL, NULL),
  );
  
  static int hrs_init(const struct device *dev)
  {
  	ARG_UNUSED(dev);
  
  	hrs_blsc = 0x01;
  
  	return 0;
  }
  
  int bt_hrs_notify(uint16_t heartrate)
  {
  	int rc;
  	static uint8_t hrm[2];
  
  	hrm[0] = 0x06; /* uint8, sensor contact */
  	hrm[1] = heartrate;
  
  	rc = bt_gatt_notify(NULL, &hrs_svc.attrs[1], &hrm, sizeof(hrm));
  
  	return rc == -ENOTCONN ? 0 : rc;
  }
  
  SYS_INIT(hrs_init, APPLICATION, CONFIG_APPLICATION_INIT_PRIORITY);
  