mbed-os/targets/TARGET_Silicon_Labs/TARGET_EFM32/sleep.c

104 lines
3.4 KiB
C

/***************************************************************************//**
* @file sleep.c
*******************************************************************************
* @section License
* <b>(C) Copyright 2015 Silicon Labs, http://www.silabs.com</b>
*******************************************************************************
*
* 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 "device.h"
#if DEVICE_SLEEP
#include "sleep_api.h"
#include "sleepmodes.h"
#include "em_emu.h"
#include "mbed_critical.h"
uint32_t sleep_block_counter[NUM_SLEEP_MODES] = {0};
/**
* Sleep mode.
* Enter the lowest possible sleep mode that is not blocked by ongoing activity.
*/
void hal_sleep(void)
{
if (sleep_block_counter[0] > 0) {
/* Blocked everything below EM0, so just return */
return;
} else if (sleep_block_counter[1] > 0) {
/* Blocked everything below EM1, enter EM1 */
EMU_EnterEM1();
} else if (sleep_block_counter[2] > 0) {
/* Blocked everything below EM2, enter EM2 */
EMU_EnterEM2(true);
} else {
/* Blocked everything below EM3, enter EM3 */
EMU_EnterEM3(true);
} /* Never enter EM4, as mbed has no way of configuring EM4 wakeup */
return;
}
/**
* Deep Sleep mode.
* Enter Energy Mode 2, turning off all high-frequency clocks.
*
* In EM2 the high frequency oscillator is turned off, but with the 32.768 kHz
* oscillator running, selected low energy peripherals (LCD, RTC, LETIMER,
* PCNT, LEUART, I2C, LESENSE, OPAMP, USB, WDOG and ACMP) are still
* available. This gives a high degree of autonomous operation with a current
* consumption as low as 1.1 μA with RTC enabled. Power-on Reset, Brown-out
* Detection and full RAM and CPU retention is also included.
*/
void hal_deepsleep(void)
{
EMU_EnterEM2(true);
}
/** Block the microcontroller from sleeping below a certain mode
*
* This will block sleep() from entering an energy mode below the one given.
* -- To be called by peripheral HAL's --
*
* After the peripheral is finished with the operation, it should call unblock with the same state
*
*/
void blockSleepMode(sleepstate_enum minimumMode)
{
core_util_critical_section_enter();
sleep_block_counter[minimumMode]++;
core_util_critical_section_exit();
}
/** Unblock the microcontroller from sleeping below a certain mode
*
* This will unblock sleep() from entering an energy mode below the one given.
* -- To be called by peripheral HAL's --
*
* This should be called after all transactions on a peripheral are done.
*/
void unblockSleepMode(sleepstate_enum minimumMode)
{
core_util_critical_section_enter();
if(sleep_block_counter[minimumMode] > 0) {
sleep_block_counter[minimumMode]--;
}
core_util_critical_section_exit();
}
#endif