mbed_sleep_manager.c

00001 /* mbed Microcontroller Library
00002  * Copyright (c) 2017 ARM Limited
00003  *
00004  * Licensed under the Apache License, Version 2.0 (the "License");
00005  * you may not use this file except in compliance with the License.
00006  * You may obtain a copy of the License at
00007  *
00008  *     http://www.apache.org/licenses/LICENSE-2.0
00009  *
00010  * Unless required by applicable law or agreed to in writing, software
00011  * distributed under the License is distributed on an "AS IS" BASIS,
00012  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00013  * See the License for the specific language governing permissions and
00014  * limitations under the License.
00015  */
00016 
00017 #include "mbed_sleep.h"
00018 #include "mbed_critical.h"
00019 #include "sleep_api.h"
00020 #include "mbed_error.h"
00021 #include <limits.h>
00022 
00023 #if DEVICE_SLEEP
00024 
00025 // deep sleep locking counter. A target is allowed to deep sleep if counter == 0
00026 static uint16_t deep_sleep_lock = 0U;
00027 
00028 void sleep_manager_lock_deep_sleep(void)
00029 {
00030     core_util_critical_section_enter();
00031     if (deep_sleep_lock == USHRT_MAX) {
00032         core_util_critical_section_exit();
00033         error("Deep sleep lock would overflow (> USHRT_MAX)");
00034     }
00035     core_util_atomic_incr_u16(&deep_sleep_lock, 1);
00036     core_util_critical_section_exit();
00037 }
00038 
00039 void sleep_manager_unlock_deep_sleep(void)
00040 {
00041     core_util_critical_section_enter();
00042     if (deep_sleep_lock == 0) {
00043         core_util_critical_section_exit();
00044         error("Deep sleep lock would underflow (< 0)");
00045     }
00046     core_util_atomic_decr_u16(&deep_sleep_lock, 1);
00047     core_util_critical_section_exit();
00048 }
00049 
00050 bool sleep_manager_can_deep_sleep(void)
00051 {
00052     return deep_sleep_lock == 0 ? true : false;
00053 }
00054 
00055 void sleep_manager_sleep_auto(void)
00056 {
00057     core_util_critical_section_enter();
00058 // debug profile should keep debuggers attached, no deep sleep allowed
00059 #ifdef MBED_DEBUG
00060     hal_sleep();
00061 #else
00062     if (sleep_manager_can_deep_sleep()) {
00063         hal_deepsleep();
00064     } else {
00065         hal_sleep();
00066     }
00067 #endif
00068     core_util_critical_section_exit();
00069 }
00070 
00071 #else
00072 
00073 // locking is valid only if DEVICE_SLEEP is defined
00074 // we provide empty implementation
00075 
00076 void sleep_manager_lock_deep_sleep(void)
00077 {
00078 
00079 }
00080 
00081 void sleep_manager_unlock_deep_sleep(void)
00082 {
00083 
00084 }
00085 
00086 bool sleep_manager_can_deep_sleep(void)
00087 {
00088     // no sleep implemented
00089     return false;
00090 }
00091 
00092 #endif