DeepSleepLock.h

00001 /* mbed Microcontroller Library
00002  * Copyright (c) 2017 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 #ifndef MBED_DEEPSLEEPLOCK_H
00018 #define MBED_DEEPSLEEPLOCK_H
00019 
00020 #include <limits.h>
00021 #include "platform/mbed_power_mgmt.h"
00022 #include "platform/mbed_critical.h"
00023 
00024 namespace mbed {
00025 
00026 /** \addtogroup platform */
00027 /** @{*/
00028 /**
00029  * \defgroup platform_DeepSleepLock DeepSleepLock functions
00030  * @{
00031  */
00032 
00033 /** RAII object for disabling, then restoring the deep sleep mode
00034   * Usage:
00035   * @code
00036   *
00037   * void f() {
00038   *     // some code here
00039   *     {
00040   *         DeepSleepLock lock;
00041   *         // Code in this block will run with the deep sleep mode locked
00042   *     }
00043   *     // deep sleep mode will be restored to their previous state
00044   * }
00045   * @endcode
00046   */
00047 class DeepSleepLock {
00048 private:
00049     uint16_t _lock_count;
00050 
00051 public:
00052     DeepSleepLock(): _lock_count(1)
00053     {
00054         sleep_manager_lock_deep_sleep();
00055     }
00056 
00057     ~DeepSleepLock()
00058     {
00059         if (_lock_count) {
00060             sleep_manager_unlock_deep_sleep();
00061         }
00062     }
00063 
00064     /** Mark the start of a locked deep sleep section
00065      */
00066     void lock()
00067     {
00068         uint16_t count = core_util_atomic_incr_u16(&_lock_count, 1);
00069         if (1 == count) {
00070             sleep_manager_lock_deep_sleep();
00071         }
00072         if (0 == count) {
00073             MBED_ERROR1(MBED_MAKE_ERROR(MBED_MODULE_PLATFORM, MBED_ERROR_CODE_OVERFLOW), "DeepSleepLock overflow (> USHRT_MAX)", count);
00074         }
00075     }
00076 
00077     /** Mark the end of a locked deep sleep section
00078      */
00079     void unlock()
00080     {
00081         uint16_t count = core_util_atomic_decr_u16(&_lock_count, 1);
00082         if (count == 0) {
00083             sleep_manager_unlock_deep_sleep();
00084         }
00085         if (count == USHRT_MAX) {
00086             core_util_critical_section_exit();
00087             MBED_ERROR1(MBED_MAKE_ERROR(MBED_MODULE_PLATFORM, MBED_ERROR_CODE_UNDERFLOW), "DeepSleepLock underflow (< 0)", count);
00088         }
00089     }
00090 };
00091 
00092 /**@}*/
00093 
00094 /**@}*/
00095 
00096 
00097 }
00098 
00099 #endif