nuttx/drivers/power/pm_checkstate.c
Alin Jerpelea 014fe97877 NuttX: Matias Nitsche: update licenses to Apache
Matias Nitsche has submitted the ICLA and we can migrate the licenses
 to Apache.

Gregory Nutt has submitted the SGA and we can migrate the licenses
 to Apache.

Signed-off-by: Alin Jerpelea <alin.jerpelea@sony.com>
2021-04-01 12:13:12 -05:00

81 lines
3.1 KiB
C

/****************************************************************************
* drivers/power/pm_checkstate.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <assert.h>
#include <nuttx/power/pm.h>
#include <nuttx/clock.h>
#include <nuttx/irq.h>
#include "pm.h"
#ifdef CONFIG_PM
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: pm_checkstate
*
* Description:
* This function is called from the MCU-specific IDLE loop to monitor the
* the power management conditions. This function returns the "recommended"
* power management state based on the PM policy applied by the currently
* chosen governor. The IDLE loop must call pm_changestate() in order to
* make the state change, which will interact with all drivers registered
* with the PM system.
*
* These two steps are separated because the plaform-specific IDLE loop may
* have additional situational information that is not available to the
* the PM sub-system. For example, the IDLE loop may know that the
* battery charge level is very low and may force lower power states
* even if there is activity.
*
* NOTE: That these two steps are separated in time and, hence, the IDLE
* loop could be suspended for a long period of time between calling
* pm_checkstate() and pm_changestate(). The IDLE loop may need to make
* these calls atomic by either disabling interrupts until the state change
* is completed.
*
* Input Parameters:
* domain - the PM domain to check
*
* Returned Value:
* The recommended power management state.
*
****************************************************************************/
enum pm_state_e pm_checkstate(int domain)
{
DEBUGASSERT(domain >= 0 && domain < CONFIG_PM_NDOMAINS &&
g_pmglobals.governor->checkstate);
return g_pmglobals.governor->checkstate(domain);
}
#endif /* CONFIG_PM */