bluetooth: services: added current time service

- added ctc implementation
- updated Kconfig & CMake files
- updated service doc

Signed-off-by: Anuj Pathak <anuj@croxel.com>
This commit is contained in:
Anuj Pathak 2024-08-22 15:29:41 +05:30 committed by Carles Cufí
commit 957d59814b
7 changed files with 368 additions and 0 deletions

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@ -8,6 +8,11 @@ Battery Service
.. doxygengroup:: bt_bas
Current Time Service
********************
.. doxygengroup:: bt_cts
Heart Rate Service
******************

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@ -0,0 +1,148 @@
/*
* Copyright (c) 2024 Croxel Inc.
*
* SPDX-License-Identifier: Apache-2.0
*/
#ifndef ZEPHYR_INCLUDE_BLUETOOTH_SERVICES_CTS_H_
#define ZEPHYR_INCLUDE_BLUETOOTH_SERVICES_CTS_H_
/**
* @brief Current Time Service (CTS)
* @defgroup bt_cts Current Time Service (CTS)
* @ingroup bluetooth
* @{
*
*/
#include <stdint.h>
#include <zephyr/posix/time.h>
#ifdef __cplusplus
extern "C" {
#endif
/**
* @brief CTS time update reason bits as defined in the specification
*/
enum bt_cts_update_reason {
/* Unknown reason of update no bit is set */
BT_CTS_UPDATE_REASON_UNKNOWN = 0,
/* When time is changed manually e.g. through UI */
BT_CTS_UPDATE_REASON_MANUAL = BIT(0),
/* If time is changed through external reference */
BT_CTS_UPDATE_REASON_EXTERNAL_REF = BIT(1),
/* time changed due to timezone adjust */
BT_CTS_UPDATE_REASON_TIME_ZONE_CHANGE = BIT(2),
/* time changed due to dst offset change */
BT_CTS_UPDATE_REASON_DAYLIGHT_SAVING = BIT(3),
};
/**
* @brief Current Time service data format, Please refer to
* specifications for more details
*/
struct bt_cts_time_format {
uint16_t year;
uint8_t mon;
uint8_t mday;
uint8_t hours;
uint8_t min;
uint8_t sec;
uint8_t wday;
uint8_t fractions256;
uint8_t reason;
} __packed;
/** @brief Current Time Service callback structure */
struct bt_cts_cb {
/** @brief Current Time Service notifications changed
*
* @param enabled True if notifications are enabled, false if disabled
*/
void (*notification_changed)(bool enabled);
/**
* @brief The Current Time has been updated by a peer.
* It is the responsibility of the application to store the new time.
*
* @param cts_time [IN] updated time
*
* @return 0 application has decoded it successfully
* @return negative error codes on failure
*
*/
int (*cts_time_write)(struct bt_cts_time_format *cts_time);
/**
* @brief When current time Read request or notification is triggered, CTS uses
* this callback to retrieve current time information from application. Application
* must implement it and provide cts formatted current time information
*
* @note this callback is mandatory
*
* @param cts_time [IN] updated time
*
* @return 0 application has encoded it successfully
* @return negative error codes on failure
*/
int (*fill_current_cts_time)(struct bt_cts_time_format *cts_time);
};
/**
* @brief This API should be called at application init.
* it is safe to call this API before or after bt_enable API
*
* @param cb pointer to required callback
*
* @return 0 on success
* @return negative error codes on failure
*/
int bt_cts_init(const struct bt_cts_cb *cb);
/**
* @brief Notify all connected clients that have enabled the
* current time update notification
*
* @param reason update reason to be sent to the clients
*
* @return 0 on success
* @return negative error codes on failure
*/
int bt_cts_send_notification(enum bt_cts_update_reason reason);
/**
* @brief Helper API to decode CTS formatted time into milliseconds since epoch
*
* @note @kconfig{CONFIG_BT_CTS_HELPER_API} needs to be enabled to use this API.
*
* @param ct_time [IN] cts time formatted time
* @param unix_ms [OUT] pointer to store parsed millisecond since epoch
*
* @return 0 on success
* @return negative error codes on failure
*/
int bt_cts_time_to_unix_ms(const struct bt_cts_time_format *ct_time, int64_t *unix_ms);
/**
* @brief Helper API to encode milliseconds since epoch to CTS formatted time
*
* @note @kconfig{CONFIG_BT_CTS_HELPER_API} needs to be enabled to use this API.
*
* @param ct_time [OUT] Pointer to store CTS formatted time
* @param unix_ms [IN] milliseconds since epoch to be converted
*
* @return 0 on success
* @return negative error codes on failure
*/
int bt_cts_time_from_unix_ms(struct bt_cts_time_format *ct_time, int64_t unix_ms);
#ifdef __cplusplus
}
#endif
/**
* @}
*/
#endif /* ZEPHYR_INCLUDE_BLUETOOTH_SERVICES_CTS_H_ */

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@ -492,6 +492,14 @@ module-str = BAS
source "subsys/logging/Kconfig.template.log_config"
endif # BT_BAS
# CTS
if BT_CTS
module = BT_CTS
module-str = CTS
source "subsys/logging/Kconfig.template.log_config"
endif # BT_CTS
# HRS
if BT_HRS

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@ -3,6 +3,8 @@
zephyr_sources_ifdef(CONFIG_BT_DIS dis.c)
zephyr_sources_ifdef(CONFIG_BT_CTS cts.c)
zephyr_sources_ifdef(CONFIG_BT_HRS hrs.c)
zephyr_sources_ifdef(CONFIG_BT_TPS tps.c)

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@ -8,6 +8,8 @@ menu "GATT Services"
rsource "Kconfig.dis"
rsource "Kconfig.cts"
rsource "Kconfig.hrs"
rsource "Kconfig.tps"

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@ -0,0 +1,14 @@
# Bluetooth GATT Battery service
# Copyright (c) 2024 Croxel Inc.
# SPDX-License-Identifier: Apache-2.0
config BT_CTS
bool "GATT Current Time service"
if BT_CTS
config BT_CTS_HELPER_API
bool "Helper APIs to encode and decode CTS formatted time"
endif

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@ -0,0 +1,189 @@
/** @file
* @brief GATT Current Time Service
*/
/*
* Copyright (c) 2024 Croxel Inc.
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <stdbool.h>
#include <zephyr/sys/byteorder.h>
#include <zephyr/posix/time.h>
#include <zephyr/bluetooth/conn.h>
#include <zephyr/bluetooth/gatt.h>
#include <zephyr/bluetooth/uuid.h>
#include <zephyr/bluetooth/services/cts.h>
#include <zephyr/logging/log.h>
LOG_MODULE_REGISTER(cts, CONFIG_BT_CTS_LOG_LEVEL);
#define BT_CTS_ATT_ERR_VALUES_IGNORED 0x80
#define BT_CTS_FRACTION_256_MAX_VALUE 255
static const struct bt_cts_cb *cts_cb;
#ifdef CONFIG_BT_CTS_HELPER_API
#include <time.h>
#include <zephyr/sys/timeutil.h>
int bt_cts_time_to_unix_ms(const struct bt_cts_time_format *ct_time, int64_t *unix_ms)
{
struct tm date_time;
/* fill date time structure */
date_time.tm_year = sys_le16_to_cpu(ct_time->year); /* year (little endian) */
date_time.tm_year -= TIME_UTILS_BASE_YEAR;
date_time.tm_mon = ct_time->mon - 1; /* month start from 1, but need from 0 */
date_time.tm_mday = ct_time->mday; /* day of month */
date_time.tm_hour = ct_time->hours; /* hours of day */
date_time.tm_min = ct_time->min; /* minute of hour */
date_time.tm_sec = ct_time->sec; /* seconds of minute */
date_time.tm_wday = ct_time->wday % 7; /* for sundays convert to 0, else keep same */
LOG_DBG("CTS Write Time: %d/%d/%d %d:%d:%d", date_time.tm_year, date_time.tm_mon,
date_time.tm_mday, date_time.tm_hour, date_time.tm_min, date_time.tm_sec);
/* get unit timestamp from datetime */
(*unix_ms) = timeutil_timegm64(&date_time);
if ((*unix_ms) == ((time_t)-1)) {
return -EOVERFLOW;
}
LOG_DBG("CTS Write Unix: %lld", (*unix_ms));
(*unix_ms) *= MSEC_PER_SEC;
/* add fraction 256 part*/
(*unix_ms) += ((ct_time->fractions256 * MSEC_PER_SEC) / BT_CTS_FRACTION_256_MAX_VALUE);
return 0;
}
int bt_cts_time_from_unix_ms(struct bt_cts_time_format *ct_time, int64_t unix_ms)
{
struct tm date_time;
time_t unix_ts = unix_ms / MSEC_PER_SEC;
/* 'Fractions 256 part of 'Exact Time 256' */
unix_ms %= MSEC_PER_SEC;
unix_ms *= BT_CTS_FRACTION_256_MAX_VALUE;
unix_ms /= MSEC_PER_SEC;
ct_time->fractions256 = unix_ms;
/* convert unix_ts to */
LOG_DBG("CTS Read Unix: %lld", unix_ts);
/* generate date time from unix timestamp */
if (gmtime_r(&unix_ts, &date_time) == NULL) {
return -EOVERFLOW;
}
date_time.tm_year += TIME_UTILS_BASE_YEAR;
LOG_DBG("CTS Read Time: %d/%d/%d %d:%d:%d", date_time.tm_year, date_time.tm_mon,
date_time.tm_mday, date_time.tm_hour, date_time.tm_min, date_time.tm_sec);
/* 'Exact Time 256' contains 'Day Date Time' which contains
* 'Date Time' - characteristic contains fields for:
* year, month, day, hours, minutes and seconds.
*/
ct_time->year = sys_cpu_to_le16(date_time.tm_year);
ct_time->mon = date_time.tm_mon + 1; /* months starting from 1 */
ct_time->mday = date_time.tm_mday; /* Day of month */
ct_time->hours = date_time.tm_hour; /* hours */
ct_time->min = date_time.tm_min; /* minutes */
ct_time->sec = date_time.tm_sec; /* seconds */
/* day of week starting from 1-monday, 7-sunday */
ct_time->wday = date_time.tm_wday;
if (ct_time->wday == 0) {
ct_time->wday = 7; /* sunday is represented as 7 */
}
return 0;
}
#endif /* CONFIG_BT_CTS_HELPER_API */
static void ct_ccc_cfg_changed(const struct bt_gatt_attr *attr, uint16_t value)
{
bool notif_enabled = (value == BT_GATT_CCC_NOTIFY);
LOG_INF("CTS Notifications %s", notif_enabled ? "enabled" : "disabled");
if (cts_cb->notification_changed) {
cts_cb->notification_changed(notif_enabled);
}
}
static ssize_t read_ct(struct bt_conn *conn, const struct bt_gatt_attr *attr, void *buf,
uint16_t len, uint16_t offset)
{
int err;
struct bt_cts_time_format ct_time;
err = cts_cb->fill_current_cts_time(&ct_time);
ct_time.reason = BT_CTS_UPDATE_REASON_UNKNOWN;
if (!err) {
return bt_gatt_attr_read(conn, attr, buf, len, offset, &ct_time, sizeof(ct_time));
} else {
return BT_GATT_ERR(BT_ATT_ERR_OUT_OF_RANGE);
}
}
static ssize_t write_ct(struct bt_conn *conn, const struct bt_gatt_attr *attr, const void *buf,
uint16_t len, uint16_t offset, uint8_t flags)
{
int err;
struct bt_cts_time_format ct_time;
if (cts_cb->cts_time_write == NULL) {
return BT_GATT_ERR(BT_ATT_ERR_INSUFFICIENT_RESOURCES);
}
if ((offset != 0) || (offset + len != sizeof(ct_time))) {
return BT_GATT_ERR(BT_ATT_ERR_INVALID_OFFSET);
}
memcpy(&ct_time, buf, sizeof(ct_time));
err = cts_cb->cts_time_write(&ct_time);
if (err) {
return BT_GATT_ERR(BT_CTS_ATT_ERR_VALUES_IGNORED);
}
err = bt_cts_send_notification(BT_CTS_UPDATE_REASON_MANUAL);
if (err) {
return BT_GATT_ERR(BT_ATT_ERR_UNLIKELY);
}
return len;
}
/* Current Time Service Declaration */
BT_GATT_SERVICE_DEFINE(cts_svc, BT_GATT_PRIMARY_SERVICE(BT_UUID_CTS),
BT_GATT_CHARACTERISTIC(BT_UUID_CTS_CURRENT_TIME,
BT_GATT_CHRC_READ | BT_GATT_CHRC_WRITE |
BT_GATT_CHRC_NOTIFY,
BT_GATT_PERM_READ | BT_GATT_PERM_WRITE, read_ct,
write_ct, NULL),
BT_GATT_CCC(ct_ccc_cfg_changed, BT_GATT_PERM_READ | BT_GATT_PERM_WRITE));
int bt_cts_init(const struct bt_cts_cb *cb)
{
__ASSERT(cb == NULL, "Current Time service need valid `struct bt_cts_cb` callback");
__ASSERT(cb->fill_current_cts_time == NULL,
"`fill_current_cts_time` callback api is required for functioning of CTS");
if (!cb || !cb->fill_current_cts_time) {
return -EINVAL;
}
cts_cb = cb;
return 0;
}
int bt_cts_send_notification(enum bt_cts_update_reason reason)
{
int err;
struct bt_cts_time_format ct_time;
err = cts_cb->fill_current_cts_time(&ct_time);
ct_time.reason = reason;
if (err) {
return err;
}
return bt_gatt_notify(NULL, &cts_svc.attrs[1], &ct_time, sizeof(ct_time));
}