mbed-os/targets/TARGET_NUVOTON/nu_timer.h

94 lines
2.5 KiB
C

/* mbed Microcontroller Library
* Copyright (c) 2015-2016 Nuvoton
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef NU_TIMER_H
#define NU_TIMER_H
#include <stdint.h>
#include <stdbool.h>
#include "cmsis.h"
#include "mbed_power_mgmt.h"
#include "mbed_critical.h"
#include "ticker_api.h"
#include "us_ticker_api.h"
#ifdef __cplusplus
extern "C" {
#endif
/* A simple count-down timer used for Nuvoton ported drivers
*
* NOTE: nu_countdown_init must be paired with nu_countdown_free.
*
* Example:
* nu_countdown_ctx_s ctx;
*
* // Set up 2 ms timeout
* nu_countdown_init(&ctx, 2000);
*
* // Timed-wait for a task
* while (true) {
* // Poll the task
*
* if (nu_countdown_expired(&ctx)) {
* // Timeout
* }
* }
*
* // Must pair nu_countdown_init with nu_countdown_free in the end
* nu_countdown_free(&ctx);
*/
struct nu_countdown_ctx_s {
const ticker_data_t * _ticker_data; // Hold ticker_data_t
us_timestamp_t _interval_end_us; // End of interval in us
bool _expired; // Expired or not
};
__STATIC_INLINE void nu_countdown_init(struct nu_countdown_ctx_s *ctx, us_timestamp_t interval_us)
{
core_util_critical_section_enter();
sleep_manager_lock_deep_sleep();
ctx->_ticker_data = get_us_ticker_data();
ctx->_interval_end_us = ticker_read_us(ctx->_ticker_data) + interval_us;
ctx->_expired = false;
core_util_critical_section_exit();
}
__STATIC_INLINE bool nu_countdown_expired(struct nu_countdown_ctx_s *ctx)
{
core_util_critical_section_enter();
if (! ctx->_expired) {
ctx->_expired = ticker_read_us(ctx->_ticker_data) >= ctx->_interval_end_us;
}
core_util_critical_section_exit();
return ctx->_expired;
}
__STATIC_INLINE void nu_countdown_free(struct nu_countdown_ctx_s *ctx)
{
core_util_critical_section_enter();
sleep_manager_unlock_deep_sleep();
core_util_critical_section_exit();
}
#ifdef __cplusplus
}
#endif
#endif