/**************************************************************************** * drivers/power/pm_activity.c * * Copyright (C) 2011-2012, 2016 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * 3. Neither the name NuttX nor the names of its contributors may be * used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include #include #include "pm.h" #ifdef CONFIG_PM /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: pm_activity * * Description: * This function is called by a device driver to indicate that it is * performing meaningful activities (non-idle). This increments an activity * count and/or will restart a idle timer and prevent entering reduced * power states. * * Input Parameters: * domain - The domain of the PM activity * priority - Activity priority, range 0-9. Larger values correspond to * higher priorities. Higher priority activity can prevent the system * from entering reduced power states for a longer period of time. * * As an example, a button press might be higher priority activity because * it means that the user is actively interacting with the device. * * Returned Value: * None. * * Assumptions: * This function may be called from an interrupt handler (this is the ONLY * PM function that may be called from an interrupt handler!). * ****************************************************************************/ void pm_activity(int domain, int priority) { FAR struct pm_domain_s *pdom; clock_t now, elapsed; uint32_t accum; irqstate_t flags; /* Get a convenience pointer to minimize all of the indexing */ DEBUGASSERT(domain >= 0 && domain < CONFIG_PM_NDOMAINS); pdom = &g_pmglobals.domain[domain]; /* Just increment the activity count in the current time slice. The priority * is simply the number of counts that are added. */ if (priority > 0) { /* Add the priority to the accumulated counts in a critical section. */ flags = enter_critical_section(); accum = (uint32_t)pdom->accum + priority; /* Make sure that we do not overflow the underlying uint16_t representation */ if (accum > INT16_MAX) { accum = INT16_MAX; } /* Save the updated count */ pdom->accum = (int16_t)accum; /* Check the elapsed time. In periods of low activity, time slicing is * controlled by IDLE loop polling; in periods of higher activity, time * slicing is controlled by driver activity. In either case, the duration * of the time slice is only approximate; during times of heavy activity, * time slices may be become longer and the activity level may be over- * estimated. */ now = clock_systimer(); elapsed = now - pdom->stime; if (elapsed >= TIME_SLICE_TICKS) { int16_t tmp; /* Sample the count, reset the time and count, and assess the PM * state. This is an atomic operation because interrupts are * still disabled. */ tmp = pdom->accum; pdom->stime = now; pdom->accum = 0; (void)pm_update(domain, tmp); } leave_critical_section(flags); } } /**************************************************************************** * Name: pm_stay * * Description: * This function is called by a device driver to indicate that it is * performing meaningful activities (non-idle), needs the power at kept * last the specified level. * * Input Parameters: * domain - The domain of the PM activity * state - The state want to stay. * * As an example, media player might stay in normal state during playback. * * Returned Value: * None. * * Assumptions: * This function may be called from an interrupt handler. * ****************************************************************************/ void pm_stay(int domain, enum pm_state_e state) { FAR struct pm_domain_s *pdom; irqstate_t flags; /* Get a convenience pointer to minimize all of the indexing */ DEBUGASSERT(domain >= 0 && domain < CONFIG_PM_NDOMAINS); pdom = &g_pmglobals.domain[domain]; flags = enter_critical_section(); DEBUGASSERT(state < PM_COUNT); DEBUGASSERT(pdom->stay[state] < UINT16_MAX); pdom->stay[state]++; leave_critical_section(flags); } /**************************************************************************** * Name: pm_relax * * Description: * This function is called by a device driver to indicate that it is * idle now, could relax the previous requested power level. * * Input Parameters: * domain - The domain of the PM activity * state - The state want to relax. * * As an example, media player might relax power level after playback. * * Returned Value: * None. * * Assumptions: * This function may be called from an interrupt handler. * ****************************************************************************/ void pm_relax(int domain, enum pm_state_e state) { FAR struct pm_domain_s *pdom; irqstate_t flags; /* Get a convenience pointer to minimize all of the indexing */ DEBUGASSERT(domain >= 0 && domain < CONFIG_PM_NDOMAINS); pdom = &g_pmglobals.domain[domain]; flags = enter_critical_section(); DEBUGASSERT(state < PM_COUNT); DEBUGASSERT(pdom->stay[state] > 0); pdom->stay[state]--; leave_critical_section(flags); } /**************************************************************************** * Name: pm_staycount * * Description: * This function is called to get current stay count. * * Input Parameters: * domain - The domain of the PM activity * state - The state want to relax. * * Returned Value: * Current pm stay count * * Assumptions: * This function may be called from an interrupt handler. * ****************************************************************************/ uint32_t pm_staycount(int domain, enum pm_state_e state) { FAR struct pm_domain_s *pdom; /* Get a convenience pointer to minimize all of the indexing */ DEBUGASSERT(domain >= 0 && domain < CONFIG_PM_NDOMAINS); pdom = &g_pmglobals.domain[domain]; return pdom->stay[state]; } #endif /* CONFIG_PM */