text: /* mbed Microcontroller Library
   * Copyright (c) 2006-2019 ARM Limited
   * SPDX-License-Identifier: Apache-2.0
   *
   * 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.
   */
  #include "drivers/Timer.h"
  #include "hal/ticker_api.h"
  #include "hal/us_ticker_api.h"
  #include "platform/mbed_critical.h"
  #include "platform/mbed_power_mgmt.h"
  
  namespace mbed {
  
  Timer::Timer() : _running(), _start(), _time(), _ticker_data(get_us_ticker_data()), _lock_deepsleep(true)
  {
      reset();
  }
  
  Timer::Timer(const ticker_data_t *data) : _running(), _start(), _time(), _ticker_data(data),
      _lock_deepsleep(!data->interface->runs_in_deep_sleep)
  {
      reset();
  }
  
  Timer::~Timer()
  {
      core_util_critical_section_enter();
      if (_running) {
          if (_lock_deepsleep) {
              sleep_manager_unlock_deep_sleep();
          }
      }
      _running = 0;
      core_util_critical_section_exit();
  }
  
  void Timer::start()
  {
      core_util_critical_section_enter();
      if (!_running) {
          if (_lock_deepsleep) {
              sleep_manager_lock_deep_sleep();
          }
          _start = ticker_read_us(_ticker_data);
          _running = 1;
      }
      core_util_critical_section_exit();
  }
  
  void Timer::stop()
  {
      core_util_critical_section_enter();
      _time += slicetime();
      if (_running) {
          if (_lock_deepsleep) {
              sleep_manager_unlock_deep_sleep();
          }
      }
      _running = 0;
      core_util_critical_section_exit();
  }
  
  int Timer::read_us()
  {
      return read_high_resolution_us();
  }
  
  float Timer::read()
  {
      return (float)read_high_resolution_us() / 1000000.0f;
  }
  
  int Timer::read_ms()
  {
      return read_high_resolution_us() / 1000;
  }
  
  us_timestamp_t Timer::read_high_resolution_us()
  {
      core_util_critical_section_enter();
      us_timestamp_t time = _time + slicetime();
      core_util_critical_section_exit();
      return time;
  }
  
  us_timestamp_t Timer::slicetime()
  {
      us_timestamp_t ret = 0;
      core_util_critical_section_enter();
      if (_running) {
          ret = ticker_read_us(_ticker_data) - _start;
      }
      core_util_critical_section_exit();
      return ret;
  }
  
  void Timer::reset()
  {
      core_util_critical_section_enter();
      _start = ticker_read_us(_ticker_data);
      _time = 0;
      core_util_critical_section_exit();
  }
  
  Timer::operator float()
  {
      return read();
  }
  
  } // namespace mbed
  