Ticker.cpp

00001 /* mbed Microcontroller Library
00002  * Copyright (c) 2006-2019 ARM Limited
00003  * SPDX-License-Identifier: Apache-2.0
00004  *
00005  * Licensed under the Apache License, Version 2.0 (the "License");
00006  * you may not use this file except in compliance with the License.
00007  * You may obtain a copy of the License at
00008  *
00009  *     http://www.apache.org/licenses/LICENSE-2.0
00010  *
00011  * Unless required by applicable law or agreed to in writing, software
00012  * distributed under the License is distributed on an "AS IS" BASIS,
00013  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00014  * See the License for the specific language governing permissions and
00015  * limitations under the License.
00016  */
00017 #include "drivers/Ticker.h"
00018 
00019 #include "drivers/TimerEvent.h"
00020 #include "hal/ticker_api.h"
00021 #include "platform/mbed_critical.h"
00022 #include "platform/mbed_power_mgmt.h"
00023 
00024 namespace mbed {
00025 
00026 Ticker::Ticker() : TimerEvent(), _delay(0), _function(0), _lock_deepsleep(true)
00027 {
00028 }
00029 
00030 // When low power ticker is in use, then do not disable deep sleep.
00031 Ticker::Ticker(const ticker_data_t *data) : TimerEvent(data), _delay(0), _function(0), _lock_deepsleep(!data->interface->runs_in_deep_sleep)
00032 {
00033 }
00034 
00035 void Ticker::detach()
00036 {
00037     core_util_critical_section_enter();
00038     remove();
00039     // unlocked only if we were attached (we locked it) and this is not low power ticker
00040     if (_function && _lock_deepsleep) {
00041         sleep_manager_unlock_deep_sleep();
00042     }
00043 
00044     _function = 0;
00045     core_util_critical_section_exit();
00046 }
00047 
00048 void Ticker::setup(us_timestamp_t t)
00049 {
00050     core_util_critical_section_enter();
00051     remove();
00052     _delay = t;
00053     insert_absolute(_delay + ticker_read_us(_ticker_data));
00054     core_util_critical_section_exit();
00055 }
00056 
00057 void Ticker::handler()
00058 {
00059     insert_absolute(event.timestamp + _delay);
00060     if (_function) {
00061         _function();
00062     }
00063 }
00064 
00065 void Ticker::attach_us(Callback<void()> func, us_timestamp_t t)
00066 {
00067     core_util_critical_section_enter();
00068     // lock only for the initial callback setup and this is not low power ticker
00069     if (!_function && _lock_deepsleep) {
00070         sleep_manager_lock_deep_sleep();
00071     }
00072     _function = func;
00073     setup(t);
00074     core_util_critical_section_exit();
00075 }
00076 
00077 } // namespace mbed