forked from luck/tmp_suning_uos_patched
230b4b376e
* pm-devfreq: PM / devfreq: create_freezable_workqueue() doesn't return an ERR_PTR PM / devfreq: Remove duplicate header file inclusion in exynos5_bus.c PM / devfreq: Use devm_* APIs in exynos5_bus.c PM / devfreq: Remove redundant platform_set_drvdata() in exynos5_bus.c PM / devfreq: Fix incorrect usage of IS_ERR_OR_NULL in exynos5_bus.c
1109 lines
28 KiB
C
1109 lines
28 KiB
C
/*
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* devfreq: Generic Dynamic Voltage and Frequency Scaling (DVFS) Framework
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* for Non-CPU Devices.
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*
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* Copyright (C) 2011 Samsung Electronics
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* MyungJoo Ham <myungjoo.ham@samsung.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/kernel.h>
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#include <linux/sched.h>
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#include <linux/errno.h>
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#include <linux/err.h>
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#include <linux/init.h>
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#include <linux/module.h>
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#include <linux/slab.h>
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#include <linux/stat.h>
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#include <linux/pm_opp.h>
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#include <linux/devfreq.h>
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#include <linux/workqueue.h>
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#include <linux/platform_device.h>
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#include <linux/list.h>
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#include <linux/printk.h>
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#include <linux/hrtimer.h>
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#include "governor.h"
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static struct class *devfreq_class;
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/*
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* devfreq core provides delayed work based load monitoring helper
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* functions. Governors can use these or can implement their own
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* monitoring mechanism.
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*/
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static struct workqueue_struct *devfreq_wq;
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/* The list of all device-devfreq governors */
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static LIST_HEAD(devfreq_governor_list);
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/* The list of all device-devfreq */
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static LIST_HEAD(devfreq_list);
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static DEFINE_MUTEX(devfreq_list_lock);
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/**
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* find_device_devfreq() - find devfreq struct using device pointer
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* @dev: device pointer used to lookup device devfreq.
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*
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* Search the list of device devfreqs and return the matched device's
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* devfreq info. devfreq_list_lock should be held by the caller.
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*/
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static struct devfreq *find_device_devfreq(struct device *dev)
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{
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struct devfreq *tmp_devfreq;
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if (unlikely(IS_ERR_OR_NULL(dev))) {
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pr_err("DEVFREQ: %s: Invalid parameters\n", __func__);
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return ERR_PTR(-EINVAL);
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}
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WARN(!mutex_is_locked(&devfreq_list_lock),
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"devfreq_list_lock must be locked.");
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list_for_each_entry(tmp_devfreq, &devfreq_list, node) {
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if (tmp_devfreq->dev.parent == dev)
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return tmp_devfreq;
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}
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return ERR_PTR(-ENODEV);
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}
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/**
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* devfreq_get_freq_level() - Lookup freq_table for the frequency
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* @devfreq: the devfreq instance
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* @freq: the target frequency
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*/
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static int devfreq_get_freq_level(struct devfreq *devfreq, unsigned long freq)
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{
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int lev;
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for (lev = 0; lev < devfreq->profile->max_state; lev++)
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if (freq == devfreq->profile->freq_table[lev])
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return lev;
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return -EINVAL;
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}
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/**
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* devfreq_update_status() - Update statistics of devfreq behavior
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* @devfreq: the devfreq instance
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* @freq: the update target frequency
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*/
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static int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
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{
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int lev, prev_lev;
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unsigned long cur_time;
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lev = devfreq_get_freq_level(devfreq, freq);
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if (lev < 0)
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return lev;
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cur_time = jiffies;
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devfreq->time_in_state[lev] +=
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cur_time - devfreq->last_stat_updated;
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if (freq != devfreq->previous_freq) {
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prev_lev = devfreq_get_freq_level(devfreq,
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devfreq->previous_freq);
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devfreq->trans_table[(prev_lev *
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devfreq->profile->max_state) + lev]++;
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devfreq->total_trans++;
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}
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devfreq->last_stat_updated = cur_time;
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return 0;
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}
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/**
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* find_devfreq_governor() - find devfreq governor from name
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* @name: name of the governor
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*
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* Search the list of devfreq governors and return the matched
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* governor's pointer. devfreq_list_lock should be held by the caller.
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*/
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static struct devfreq_governor *find_devfreq_governor(const char *name)
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{
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struct devfreq_governor *tmp_governor;
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if (unlikely(IS_ERR_OR_NULL(name))) {
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pr_err("DEVFREQ: %s: Invalid parameters\n", __func__);
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return ERR_PTR(-EINVAL);
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}
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WARN(!mutex_is_locked(&devfreq_list_lock),
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"devfreq_list_lock must be locked.");
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list_for_each_entry(tmp_governor, &devfreq_governor_list, node) {
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if (!strncmp(tmp_governor->name, name, DEVFREQ_NAME_LEN))
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return tmp_governor;
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}
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return ERR_PTR(-ENODEV);
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}
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/* Load monitoring helper functions for governors use */
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/**
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* update_devfreq() - Reevaluate the device and configure frequency.
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* @devfreq: the devfreq instance.
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*
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* Note: Lock devfreq->lock before calling update_devfreq
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* This function is exported for governors.
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*/
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int update_devfreq(struct devfreq *devfreq)
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{
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unsigned long freq;
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int err = 0;
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u32 flags = 0;
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if (!mutex_is_locked(&devfreq->lock)) {
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WARN(true, "devfreq->lock must be locked by the caller.\n");
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return -EINVAL;
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}
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if (!devfreq->governor)
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return -EINVAL;
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/* Reevaluate the proper frequency */
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err = devfreq->governor->get_target_freq(devfreq, &freq);
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if (err)
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return err;
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/*
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* Adjust the freuqency with user freq and QoS.
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*
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* List from the highest proiority
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* max_freq (probably called by thermal when it's too hot)
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* min_freq
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*/
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if (devfreq->min_freq && freq < devfreq->min_freq) {
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freq = devfreq->min_freq;
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flags &= ~DEVFREQ_FLAG_LEAST_UPPER_BOUND; /* Use GLB */
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}
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if (devfreq->max_freq && freq > devfreq->max_freq) {
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freq = devfreq->max_freq;
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flags |= DEVFREQ_FLAG_LEAST_UPPER_BOUND; /* Use LUB */
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}
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err = devfreq->profile->target(devfreq->dev.parent, &freq, flags);
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if (err)
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return err;
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if (devfreq->profile->freq_table)
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if (devfreq_update_status(devfreq, freq))
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dev_err(&devfreq->dev,
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"Couldn't update frequency transition information.\n");
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devfreq->previous_freq = freq;
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return err;
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}
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EXPORT_SYMBOL(update_devfreq);
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/**
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* devfreq_monitor() - Periodically poll devfreq objects.
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* @work: the work struct used to run devfreq_monitor periodically.
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*
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*/
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static void devfreq_monitor(struct work_struct *work)
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{
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int err;
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struct devfreq *devfreq = container_of(work,
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struct devfreq, work.work);
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mutex_lock(&devfreq->lock);
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err = update_devfreq(devfreq);
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if (err)
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dev_err(&devfreq->dev, "dvfs failed with (%d) error\n", err);
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queue_delayed_work(devfreq_wq, &devfreq->work,
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msecs_to_jiffies(devfreq->profile->polling_ms));
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mutex_unlock(&devfreq->lock);
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}
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/**
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* devfreq_monitor_start() - Start load monitoring of devfreq instance
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* @devfreq: the devfreq instance.
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*
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* Helper function for starting devfreq device load monitoing. By
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* default delayed work based monitoring is supported. Function
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* to be called from governor in response to DEVFREQ_GOV_START
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* event when device is added to devfreq framework.
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*/
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void devfreq_monitor_start(struct devfreq *devfreq)
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{
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INIT_DEFERRABLE_WORK(&devfreq->work, devfreq_monitor);
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if (devfreq->profile->polling_ms)
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queue_delayed_work(devfreq_wq, &devfreq->work,
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msecs_to_jiffies(devfreq->profile->polling_ms));
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}
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EXPORT_SYMBOL(devfreq_monitor_start);
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/**
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* devfreq_monitor_stop() - Stop load monitoring of a devfreq instance
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* @devfreq: the devfreq instance.
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*
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* Helper function to stop devfreq device load monitoing. Function
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* to be called from governor in response to DEVFREQ_GOV_STOP
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* event when device is removed from devfreq framework.
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*/
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void devfreq_monitor_stop(struct devfreq *devfreq)
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{
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cancel_delayed_work_sync(&devfreq->work);
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}
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EXPORT_SYMBOL(devfreq_monitor_stop);
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/**
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* devfreq_monitor_suspend() - Suspend load monitoring of a devfreq instance
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* @devfreq: the devfreq instance.
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*
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* Helper function to suspend devfreq device load monitoing. Function
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* to be called from governor in response to DEVFREQ_GOV_SUSPEND
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* event or when polling interval is set to zero.
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*
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* Note: Though this function is same as devfreq_monitor_stop(),
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* intentionally kept separate to provide hooks for collecting
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* transition statistics.
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*/
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void devfreq_monitor_suspend(struct devfreq *devfreq)
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{
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mutex_lock(&devfreq->lock);
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if (devfreq->stop_polling) {
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mutex_unlock(&devfreq->lock);
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return;
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}
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devfreq_update_status(devfreq, devfreq->previous_freq);
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devfreq->stop_polling = true;
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mutex_unlock(&devfreq->lock);
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cancel_delayed_work_sync(&devfreq->work);
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}
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EXPORT_SYMBOL(devfreq_monitor_suspend);
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/**
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* devfreq_monitor_resume() - Resume load monitoring of a devfreq instance
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* @devfreq: the devfreq instance.
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*
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* Helper function to resume devfreq device load monitoing. Function
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* to be called from governor in response to DEVFREQ_GOV_RESUME
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* event or when polling interval is set to non-zero.
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*/
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void devfreq_monitor_resume(struct devfreq *devfreq)
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{
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unsigned long freq;
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mutex_lock(&devfreq->lock);
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if (!devfreq->stop_polling)
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goto out;
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if (!delayed_work_pending(&devfreq->work) &&
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devfreq->profile->polling_ms)
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queue_delayed_work(devfreq_wq, &devfreq->work,
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msecs_to_jiffies(devfreq->profile->polling_ms));
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devfreq->last_stat_updated = jiffies;
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devfreq->stop_polling = false;
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if (devfreq->profile->get_cur_freq &&
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!devfreq->profile->get_cur_freq(devfreq->dev.parent, &freq))
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devfreq->previous_freq = freq;
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out:
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mutex_unlock(&devfreq->lock);
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}
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EXPORT_SYMBOL(devfreq_monitor_resume);
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/**
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* devfreq_interval_update() - Update device devfreq monitoring interval
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* @devfreq: the devfreq instance.
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* @delay: new polling interval to be set.
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*
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* Helper function to set new load monitoring polling interval. Function
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* to be called from governor in response to DEVFREQ_GOV_INTERVAL event.
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*/
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void devfreq_interval_update(struct devfreq *devfreq, unsigned int *delay)
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{
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unsigned int cur_delay = devfreq->profile->polling_ms;
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unsigned int new_delay = *delay;
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mutex_lock(&devfreq->lock);
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devfreq->profile->polling_ms = new_delay;
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if (devfreq->stop_polling)
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goto out;
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/* if new delay is zero, stop polling */
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if (!new_delay) {
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mutex_unlock(&devfreq->lock);
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cancel_delayed_work_sync(&devfreq->work);
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return;
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}
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/* if current delay is zero, start polling with new delay */
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if (!cur_delay) {
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queue_delayed_work(devfreq_wq, &devfreq->work,
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msecs_to_jiffies(devfreq->profile->polling_ms));
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goto out;
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}
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/* if current delay is greater than new delay, restart polling */
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if (cur_delay > new_delay) {
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mutex_unlock(&devfreq->lock);
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cancel_delayed_work_sync(&devfreq->work);
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mutex_lock(&devfreq->lock);
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if (!devfreq->stop_polling)
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queue_delayed_work(devfreq_wq, &devfreq->work,
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msecs_to_jiffies(devfreq->profile->polling_ms));
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}
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out:
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mutex_unlock(&devfreq->lock);
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}
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EXPORT_SYMBOL(devfreq_interval_update);
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/**
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* devfreq_notifier_call() - Notify that the device frequency requirements
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* has been changed out of devfreq framework.
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* @nb: the notifier_block (supposed to be devfreq->nb)
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* @type: not used
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* @devp: not used
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*
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* Called by a notifier that uses devfreq->nb.
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*/
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static int devfreq_notifier_call(struct notifier_block *nb, unsigned long type,
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void *devp)
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{
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struct devfreq *devfreq = container_of(nb, struct devfreq, nb);
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int ret;
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mutex_lock(&devfreq->lock);
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ret = update_devfreq(devfreq);
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mutex_unlock(&devfreq->lock);
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return ret;
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}
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/**
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* _remove_devfreq() - Remove devfreq from the list and release its resources.
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* @devfreq: the devfreq struct
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* @skip: skip calling device_unregister().
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*/
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static void _remove_devfreq(struct devfreq *devfreq, bool skip)
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{
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mutex_lock(&devfreq_list_lock);
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if (IS_ERR(find_device_devfreq(devfreq->dev.parent))) {
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mutex_unlock(&devfreq_list_lock);
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dev_warn(&devfreq->dev, "releasing devfreq which doesn't exist\n");
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return;
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}
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list_del(&devfreq->node);
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mutex_unlock(&devfreq_list_lock);
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if (devfreq->governor)
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devfreq->governor->event_handler(devfreq,
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DEVFREQ_GOV_STOP, NULL);
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|
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if (devfreq->profile->exit)
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devfreq->profile->exit(devfreq->dev.parent);
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|
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if (!skip && get_device(&devfreq->dev)) {
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device_unregister(&devfreq->dev);
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put_device(&devfreq->dev);
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}
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|
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mutex_destroy(&devfreq->lock);
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kfree(devfreq);
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}
|
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|
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/**
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* devfreq_dev_release() - Callback for struct device to release the device.
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* @dev: the devfreq device
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*
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* This calls _remove_devfreq() if _remove_devfreq() is not called.
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* Note that devfreq_dev_release() could be called by _remove_devfreq() as
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* well as by others unregistering the device.
|
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*/
|
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static void devfreq_dev_release(struct device *dev)
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{
|
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struct devfreq *devfreq = to_devfreq(dev);
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|
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_remove_devfreq(devfreq, true);
|
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}
|
|
|
|
/**
|
|
* devfreq_add_device() - Add devfreq feature to the device
|
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* @dev: the device to add devfreq feature.
|
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* @profile: device-specific profile to run devfreq.
|
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* @governor_name: name of the policy to choose frequency.
|
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* @data: private data for the governor. The devfreq framework does not
|
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* touch this value.
|
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*/
|
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struct devfreq *devfreq_add_device(struct device *dev,
|
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struct devfreq_dev_profile *profile,
|
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const char *governor_name,
|
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void *data)
|
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{
|
|
struct devfreq *devfreq;
|
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struct devfreq_governor *governor;
|
|
int err = 0;
|
|
|
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if (!dev || !profile || !governor_name) {
|
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dev_err(dev, "%s: Invalid parameters.\n", __func__);
|
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return ERR_PTR(-EINVAL);
|
|
}
|
|
|
|
mutex_lock(&devfreq_list_lock);
|
|
devfreq = find_device_devfreq(dev);
|
|
mutex_unlock(&devfreq_list_lock);
|
|
if (!IS_ERR(devfreq)) {
|
|
dev_err(dev, "%s: Unable to create devfreq for the device. It already has one.\n", __func__);
|
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err = -EINVAL;
|
|
goto err_out;
|
|
}
|
|
|
|
devfreq = kzalloc(sizeof(struct devfreq), GFP_KERNEL);
|
|
if (!devfreq) {
|
|
dev_err(dev, "%s: Unable to create devfreq for the device\n",
|
|
__func__);
|
|
err = -ENOMEM;
|
|
goto err_out;
|
|
}
|
|
|
|
mutex_init(&devfreq->lock);
|
|
mutex_lock(&devfreq->lock);
|
|
devfreq->dev.parent = dev;
|
|
devfreq->dev.class = devfreq_class;
|
|
devfreq->dev.release = devfreq_dev_release;
|
|
devfreq->profile = profile;
|
|
strncpy(devfreq->governor_name, governor_name, DEVFREQ_NAME_LEN);
|
|
devfreq->previous_freq = profile->initial_freq;
|
|
devfreq->data = data;
|
|
devfreq->nb.notifier_call = devfreq_notifier_call;
|
|
|
|
devfreq->trans_table = devm_kzalloc(dev, sizeof(unsigned int) *
|
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devfreq->profile->max_state *
|
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devfreq->profile->max_state,
|
|
GFP_KERNEL);
|
|
devfreq->time_in_state = devm_kzalloc(dev, sizeof(unsigned int) *
|
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devfreq->profile->max_state,
|
|
GFP_KERNEL);
|
|
devfreq->last_stat_updated = jiffies;
|
|
|
|
dev_set_name(&devfreq->dev, "%s", dev_name(dev));
|
|
err = device_register(&devfreq->dev);
|
|
if (err) {
|
|
put_device(&devfreq->dev);
|
|
mutex_unlock(&devfreq->lock);
|
|
goto err_dev;
|
|
}
|
|
|
|
mutex_unlock(&devfreq->lock);
|
|
|
|
mutex_lock(&devfreq_list_lock);
|
|
list_add(&devfreq->node, &devfreq_list);
|
|
|
|
governor = find_devfreq_governor(devfreq->governor_name);
|
|
if (!IS_ERR(governor))
|
|
devfreq->governor = governor;
|
|
if (devfreq->governor)
|
|
err = devfreq->governor->event_handler(devfreq,
|
|
DEVFREQ_GOV_START, NULL);
|
|
mutex_unlock(&devfreq_list_lock);
|
|
if (err) {
|
|
dev_err(dev, "%s: Unable to start governor for the device\n",
|
|
__func__);
|
|
goto err_init;
|
|
}
|
|
|
|
return devfreq;
|
|
|
|
err_init:
|
|
list_del(&devfreq->node);
|
|
device_unregister(&devfreq->dev);
|
|
err_dev:
|
|
kfree(devfreq);
|
|
err_out:
|
|
return ERR_PTR(err);
|
|
}
|
|
EXPORT_SYMBOL(devfreq_add_device);
|
|
|
|
/**
|
|
* devfreq_remove_device() - Remove devfreq feature from a device.
|
|
* @devfreq: the devfreq instance to be removed
|
|
*
|
|
* The opposite of devfreq_add_device().
|
|
*/
|
|
int devfreq_remove_device(struct devfreq *devfreq)
|
|
{
|
|
if (!devfreq)
|
|
return -EINVAL;
|
|
|
|
_remove_devfreq(devfreq, false);
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(devfreq_remove_device);
|
|
|
|
/**
|
|
* devfreq_suspend_device() - Suspend devfreq of a device.
|
|
* @devfreq: the devfreq instance to be suspended
|
|
*
|
|
* This function is intended to be called by the pm callbacks
|
|
* (e.g., runtime_suspend, suspend) of the device driver that
|
|
* holds the devfreq.
|
|
*/
|
|
int devfreq_suspend_device(struct devfreq *devfreq)
|
|
{
|
|
if (!devfreq)
|
|
return -EINVAL;
|
|
|
|
if (!devfreq->governor)
|
|
return 0;
|
|
|
|
return devfreq->governor->event_handler(devfreq,
|
|
DEVFREQ_GOV_SUSPEND, NULL);
|
|
}
|
|
EXPORT_SYMBOL(devfreq_suspend_device);
|
|
|
|
/**
|
|
* devfreq_resume_device() - Resume devfreq of a device.
|
|
* @devfreq: the devfreq instance to be resumed
|
|
*
|
|
* This function is intended to be called by the pm callbacks
|
|
* (e.g., runtime_resume, resume) of the device driver that
|
|
* holds the devfreq.
|
|
*/
|
|
int devfreq_resume_device(struct devfreq *devfreq)
|
|
{
|
|
if (!devfreq)
|
|
return -EINVAL;
|
|
|
|
if (!devfreq->governor)
|
|
return 0;
|
|
|
|
return devfreq->governor->event_handler(devfreq,
|
|
DEVFREQ_GOV_RESUME, NULL);
|
|
}
|
|
EXPORT_SYMBOL(devfreq_resume_device);
|
|
|
|
/**
|
|
* devfreq_add_governor() - Add devfreq governor
|
|
* @governor: the devfreq governor to be added
|
|
*/
|
|
int devfreq_add_governor(struct devfreq_governor *governor)
|
|
{
|
|
struct devfreq_governor *g;
|
|
struct devfreq *devfreq;
|
|
int err = 0;
|
|
|
|
if (!governor) {
|
|
pr_err("%s: Invalid parameters.\n", __func__);
|
|
return -EINVAL;
|
|
}
|
|
|
|
mutex_lock(&devfreq_list_lock);
|
|
g = find_devfreq_governor(governor->name);
|
|
if (!IS_ERR(g)) {
|
|
pr_err("%s: governor %s already registered\n", __func__,
|
|
g->name);
|
|
err = -EINVAL;
|
|
goto err_out;
|
|
}
|
|
|
|
list_add(&governor->node, &devfreq_governor_list);
|
|
|
|
list_for_each_entry(devfreq, &devfreq_list, node) {
|
|
int ret = 0;
|
|
struct device *dev = devfreq->dev.parent;
|
|
|
|
if (!strncmp(devfreq->governor_name, governor->name,
|
|
DEVFREQ_NAME_LEN)) {
|
|
/* The following should never occur */
|
|
if (devfreq->governor) {
|
|
dev_warn(dev,
|
|
"%s: Governor %s already present\n",
|
|
__func__, devfreq->governor->name);
|
|
ret = devfreq->governor->event_handler(devfreq,
|
|
DEVFREQ_GOV_STOP, NULL);
|
|
if (ret) {
|
|
dev_warn(dev,
|
|
"%s: Governor %s stop = %d\n",
|
|
__func__,
|
|
devfreq->governor->name, ret);
|
|
}
|
|
/* Fall through */
|
|
}
|
|
devfreq->governor = governor;
|
|
ret = devfreq->governor->event_handler(devfreq,
|
|
DEVFREQ_GOV_START, NULL);
|
|
if (ret) {
|
|
dev_warn(dev, "%s: Governor %s start=%d\n",
|
|
__func__, devfreq->governor->name,
|
|
ret);
|
|
}
|
|
}
|
|
}
|
|
|
|
err_out:
|
|
mutex_unlock(&devfreq_list_lock);
|
|
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL(devfreq_add_governor);
|
|
|
|
/**
|
|
* devfreq_remove_device() - Remove devfreq feature from a device.
|
|
* @governor: the devfreq governor to be removed
|
|
*/
|
|
int devfreq_remove_governor(struct devfreq_governor *governor)
|
|
{
|
|
struct devfreq_governor *g;
|
|
struct devfreq *devfreq;
|
|
int err = 0;
|
|
|
|
if (!governor) {
|
|
pr_err("%s: Invalid parameters.\n", __func__);
|
|
return -EINVAL;
|
|
}
|
|
|
|
mutex_lock(&devfreq_list_lock);
|
|
g = find_devfreq_governor(governor->name);
|
|
if (IS_ERR(g)) {
|
|
pr_err("%s: governor %s not registered\n", __func__,
|
|
governor->name);
|
|
err = PTR_ERR(g);
|
|
goto err_out;
|
|
}
|
|
list_for_each_entry(devfreq, &devfreq_list, node) {
|
|
int ret;
|
|
struct device *dev = devfreq->dev.parent;
|
|
|
|
if (!strncmp(devfreq->governor_name, governor->name,
|
|
DEVFREQ_NAME_LEN)) {
|
|
/* we should have a devfreq governor! */
|
|
if (!devfreq->governor) {
|
|
dev_warn(dev, "%s: Governor %s NOT present\n",
|
|
__func__, governor->name);
|
|
continue;
|
|
/* Fall through */
|
|
}
|
|
ret = devfreq->governor->event_handler(devfreq,
|
|
DEVFREQ_GOV_STOP, NULL);
|
|
if (ret) {
|
|
dev_warn(dev, "%s: Governor %s stop=%d\n",
|
|
__func__, devfreq->governor->name,
|
|
ret);
|
|
}
|
|
devfreq->governor = NULL;
|
|
}
|
|
}
|
|
|
|
list_del(&governor->node);
|
|
err_out:
|
|
mutex_unlock(&devfreq_list_lock);
|
|
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL(devfreq_remove_governor);
|
|
|
|
static ssize_t governor_show(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
if (!to_devfreq(dev)->governor)
|
|
return -EINVAL;
|
|
|
|
return sprintf(buf, "%s\n", to_devfreq(dev)->governor->name);
|
|
}
|
|
|
|
static ssize_t governor_store(struct device *dev, struct device_attribute *attr,
|
|
const char *buf, size_t count)
|
|
{
|
|
struct devfreq *df = to_devfreq(dev);
|
|
int ret;
|
|
char str_governor[DEVFREQ_NAME_LEN + 1];
|
|
struct devfreq_governor *governor;
|
|
|
|
ret = sscanf(buf, "%" __stringify(DEVFREQ_NAME_LEN) "s", str_governor);
|
|
if (ret != 1)
|
|
return -EINVAL;
|
|
|
|
mutex_lock(&devfreq_list_lock);
|
|
governor = find_devfreq_governor(str_governor);
|
|
if (IS_ERR(governor)) {
|
|
ret = PTR_ERR(governor);
|
|
goto out;
|
|
}
|
|
if (df->governor == governor)
|
|
goto out;
|
|
|
|
if (df->governor) {
|
|
ret = df->governor->event_handler(df, DEVFREQ_GOV_STOP, NULL);
|
|
if (ret) {
|
|
dev_warn(dev, "%s: Governor %s not stopped(%d)\n",
|
|
__func__, df->governor->name, ret);
|
|
goto out;
|
|
}
|
|
}
|
|
df->governor = governor;
|
|
strncpy(df->governor_name, governor->name, DEVFREQ_NAME_LEN);
|
|
ret = df->governor->event_handler(df, DEVFREQ_GOV_START, NULL);
|
|
if (ret)
|
|
dev_warn(dev, "%s: Governor %s not started(%d)\n",
|
|
__func__, df->governor->name, ret);
|
|
out:
|
|
mutex_unlock(&devfreq_list_lock);
|
|
|
|
if (!ret)
|
|
ret = count;
|
|
return ret;
|
|
}
|
|
static DEVICE_ATTR_RW(governor);
|
|
|
|
static ssize_t available_governors_show(struct device *d,
|
|
struct device_attribute *attr,
|
|
char *buf)
|
|
{
|
|
struct devfreq_governor *tmp_governor;
|
|
ssize_t count = 0;
|
|
|
|
mutex_lock(&devfreq_list_lock);
|
|
list_for_each_entry(tmp_governor, &devfreq_governor_list, node)
|
|
count += scnprintf(&buf[count], (PAGE_SIZE - count - 2),
|
|
"%s ", tmp_governor->name);
|
|
mutex_unlock(&devfreq_list_lock);
|
|
|
|
/* Truncate the trailing space */
|
|
if (count)
|
|
count--;
|
|
|
|
count += sprintf(&buf[count], "\n");
|
|
|
|
return count;
|
|
}
|
|
static DEVICE_ATTR_RO(available_governors);
|
|
|
|
static ssize_t cur_freq_show(struct device *dev, struct device_attribute *attr,
|
|
char *buf)
|
|
{
|
|
unsigned long freq;
|
|
struct devfreq *devfreq = to_devfreq(dev);
|
|
|
|
if (devfreq->profile->get_cur_freq &&
|
|
!devfreq->profile->get_cur_freq(devfreq->dev.parent, &freq))
|
|
return sprintf(buf, "%lu\n", freq);
|
|
|
|
return sprintf(buf, "%lu\n", devfreq->previous_freq);
|
|
}
|
|
static DEVICE_ATTR_RO(cur_freq);
|
|
|
|
static ssize_t target_freq_show(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
return sprintf(buf, "%lu\n", to_devfreq(dev)->previous_freq);
|
|
}
|
|
static DEVICE_ATTR_RO(target_freq);
|
|
|
|
static ssize_t polling_interval_show(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
return sprintf(buf, "%d\n", to_devfreq(dev)->profile->polling_ms);
|
|
}
|
|
|
|
static ssize_t polling_interval_store(struct device *dev,
|
|
struct device_attribute *attr,
|
|
const char *buf, size_t count)
|
|
{
|
|
struct devfreq *df = to_devfreq(dev);
|
|
unsigned int value;
|
|
int ret;
|
|
|
|
if (!df->governor)
|
|
return -EINVAL;
|
|
|
|
ret = sscanf(buf, "%u", &value);
|
|
if (ret != 1)
|
|
return -EINVAL;
|
|
|
|
df->governor->event_handler(df, DEVFREQ_GOV_INTERVAL, &value);
|
|
ret = count;
|
|
|
|
return ret;
|
|
}
|
|
static DEVICE_ATTR_RW(polling_interval);
|
|
|
|
static ssize_t min_freq_store(struct device *dev, struct device_attribute *attr,
|
|
const char *buf, size_t count)
|
|
{
|
|
struct devfreq *df = to_devfreq(dev);
|
|
unsigned long value;
|
|
int ret;
|
|
unsigned long max;
|
|
|
|
ret = sscanf(buf, "%lu", &value);
|
|
if (ret != 1)
|
|
return -EINVAL;
|
|
|
|
mutex_lock(&df->lock);
|
|
max = df->max_freq;
|
|
if (value && max && value > max) {
|
|
ret = -EINVAL;
|
|
goto unlock;
|
|
}
|
|
|
|
df->min_freq = value;
|
|
update_devfreq(df);
|
|
ret = count;
|
|
unlock:
|
|
mutex_unlock(&df->lock);
|
|
return ret;
|
|
}
|
|
|
|
static ssize_t min_freq_show(struct device *dev, struct device_attribute *attr,
|
|
char *buf)
|
|
{
|
|
return sprintf(buf, "%lu\n", to_devfreq(dev)->min_freq);
|
|
}
|
|
|
|
static ssize_t max_freq_store(struct device *dev, struct device_attribute *attr,
|
|
const char *buf, size_t count)
|
|
{
|
|
struct devfreq *df = to_devfreq(dev);
|
|
unsigned long value;
|
|
int ret;
|
|
unsigned long min;
|
|
|
|
ret = sscanf(buf, "%lu", &value);
|
|
if (ret != 1)
|
|
return -EINVAL;
|
|
|
|
mutex_lock(&df->lock);
|
|
min = df->min_freq;
|
|
if (value && min && value < min) {
|
|
ret = -EINVAL;
|
|
goto unlock;
|
|
}
|
|
|
|
df->max_freq = value;
|
|
update_devfreq(df);
|
|
ret = count;
|
|
unlock:
|
|
mutex_unlock(&df->lock);
|
|
return ret;
|
|
}
|
|
static DEVICE_ATTR_RW(min_freq);
|
|
|
|
static ssize_t max_freq_show(struct device *dev, struct device_attribute *attr,
|
|
char *buf)
|
|
{
|
|
return sprintf(buf, "%lu\n", to_devfreq(dev)->max_freq);
|
|
}
|
|
static DEVICE_ATTR_RW(max_freq);
|
|
|
|
static ssize_t available_frequencies_show(struct device *d,
|
|
struct device_attribute *attr,
|
|
char *buf)
|
|
{
|
|
struct devfreq *df = to_devfreq(d);
|
|
struct device *dev = df->dev.parent;
|
|
struct dev_pm_opp *opp;
|
|
ssize_t count = 0;
|
|
unsigned long freq = 0;
|
|
|
|
rcu_read_lock();
|
|
do {
|
|
opp = dev_pm_opp_find_freq_ceil(dev, &freq);
|
|
if (IS_ERR(opp))
|
|
break;
|
|
|
|
count += scnprintf(&buf[count], (PAGE_SIZE - count - 2),
|
|
"%lu ", freq);
|
|
freq++;
|
|
} while (1);
|
|
rcu_read_unlock();
|
|
|
|
/* Truncate the trailing space */
|
|
if (count)
|
|
count--;
|
|
|
|
count += sprintf(&buf[count], "\n");
|
|
|
|
return count;
|
|
}
|
|
static DEVICE_ATTR_RO(available_frequencies);
|
|
|
|
static ssize_t trans_stat_show(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
struct devfreq *devfreq = to_devfreq(dev);
|
|
ssize_t len;
|
|
int i, j;
|
|
unsigned int max_state = devfreq->profile->max_state;
|
|
|
|
if (!devfreq->stop_polling &&
|
|
devfreq_update_status(devfreq, devfreq->previous_freq))
|
|
return 0;
|
|
|
|
len = sprintf(buf, " From : To\n");
|
|
len += sprintf(buf + len, " :");
|
|
for (i = 0; i < max_state; i++)
|
|
len += sprintf(buf + len, "%8u",
|
|
devfreq->profile->freq_table[i]);
|
|
|
|
len += sprintf(buf + len, " time(ms)\n");
|
|
|
|
for (i = 0; i < max_state; i++) {
|
|
if (devfreq->profile->freq_table[i]
|
|
== devfreq->previous_freq) {
|
|
len += sprintf(buf + len, "*");
|
|
} else {
|
|
len += sprintf(buf + len, " ");
|
|
}
|
|
len += sprintf(buf + len, "%8u:",
|
|
devfreq->profile->freq_table[i]);
|
|
for (j = 0; j < max_state; j++)
|
|
len += sprintf(buf + len, "%8u",
|
|
devfreq->trans_table[(i * max_state) + j]);
|
|
len += sprintf(buf + len, "%10u\n",
|
|
jiffies_to_msecs(devfreq->time_in_state[i]));
|
|
}
|
|
|
|
len += sprintf(buf + len, "Total transition : %u\n",
|
|
devfreq->total_trans);
|
|
return len;
|
|
}
|
|
static DEVICE_ATTR_RO(trans_stat);
|
|
|
|
static struct attribute *devfreq_attrs[] = {
|
|
&dev_attr_governor.attr,
|
|
&dev_attr_available_governors.attr,
|
|
&dev_attr_cur_freq.attr,
|
|
&dev_attr_available_frequencies.attr,
|
|
&dev_attr_target_freq.attr,
|
|
&dev_attr_polling_interval.attr,
|
|
&dev_attr_min_freq.attr,
|
|
&dev_attr_max_freq.attr,
|
|
&dev_attr_trans_stat.attr,
|
|
NULL,
|
|
};
|
|
ATTRIBUTE_GROUPS(devfreq);
|
|
|
|
static int __init devfreq_init(void)
|
|
{
|
|
devfreq_class = class_create(THIS_MODULE, "devfreq");
|
|
if (IS_ERR(devfreq_class)) {
|
|
pr_err("%s: couldn't create class\n", __FILE__);
|
|
return PTR_ERR(devfreq_class);
|
|
}
|
|
|
|
devfreq_wq = create_freezable_workqueue("devfreq_wq");
|
|
if (!devfreq_wq) {
|
|
class_destroy(devfreq_class);
|
|
pr_err("%s: couldn't create workqueue\n", __FILE__);
|
|
return -ENOMEM;
|
|
}
|
|
devfreq_class->dev_groups = devfreq_groups;
|
|
|
|
return 0;
|
|
}
|
|
subsys_initcall(devfreq_init);
|
|
|
|
static void __exit devfreq_exit(void)
|
|
{
|
|
class_destroy(devfreq_class);
|
|
destroy_workqueue(devfreq_wq);
|
|
}
|
|
module_exit(devfreq_exit);
|
|
|
|
/*
|
|
* The followings are helper functions for devfreq user device drivers with
|
|
* OPP framework.
|
|
*/
|
|
|
|
/**
|
|
* devfreq_recommended_opp() - Helper function to get proper OPP for the
|
|
* freq value given to target callback.
|
|
* @dev: The devfreq user device. (parent of devfreq)
|
|
* @freq: The frequency given to target function
|
|
* @flags: Flags handed from devfreq framework.
|
|
*
|
|
* Locking: This function must be called under rcu_read_lock(). opp is a rcu
|
|
* protected pointer. The reason for the same is that the opp pointer which is
|
|
* returned will remain valid for use with opp_get_{voltage, freq} only while
|
|
* under the locked area. The pointer returned must be used prior to unlocking
|
|
* with rcu_read_unlock() to maintain the integrity of the pointer.
|
|
*/
|
|
struct dev_pm_opp *devfreq_recommended_opp(struct device *dev,
|
|
unsigned long *freq,
|
|
u32 flags)
|
|
{
|
|
struct dev_pm_opp *opp;
|
|
|
|
if (flags & DEVFREQ_FLAG_LEAST_UPPER_BOUND) {
|
|
/* The freq is an upper bound. opp should be lower */
|
|
opp = dev_pm_opp_find_freq_floor(dev, freq);
|
|
|
|
/* If not available, use the closest opp */
|
|
if (opp == ERR_PTR(-ERANGE))
|
|
opp = dev_pm_opp_find_freq_ceil(dev, freq);
|
|
} else {
|
|
/* The freq is an lower bound. opp should be higher */
|
|
opp = dev_pm_opp_find_freq_ceil(dev, freq);
|
|
|
|
/* If not available, use the closest opp */
|
|
if (opp == ERR_PTR(-ERANGE))
|
|
opp = dev_pm_opp_find_freq_floor(dev, freq);
|
|
}
|
|
|
|
return opp;
|
|
}
|
|
|
|
/**
|
|
* devfreq_register_opp_notifier() - Helper function to get devfreq notified
|
|
* for any changes in the OPP availability
|
|
* changes
|
|
* @dev: The devfreq user device. (parent of devfreq)
|
|
* @devfreq: The devfreq object.
|
|
*/
|
|
int devfreq_register_opp_notifier(struct device *dev, struct devfreq *devfreq)
|
|
{
|
|
struct srcu_notifier_head *nh;
|
|
int ret = 0;
|
|
|
|
rcu_read_lock();
|
|
nh = dev_pm_opp_get_notifier(dev);
|
|
if (IS_ERR(nh))
|
|
ret = PTR_ERR(nh);
|
|
rcu_read_unlock();
|
|
if (!ret)
|
|
ret = srcu_notifier_chain_register(nh, &devfreq->nb);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* devfreq_unregister_opp_notifier() - Helper function to stop getting devfreq
|
|
* notified for any changes in the OPP
|
|
* availability changes anymore.
|
|
* @dev: The devfreq user device. (parent of devfreq)
|
|
* @devfreq: The devfreq object.
|
|
*
|
|
* At exit() callback of devfreq_dev_profile, this must be included if
|
|
* devfreq_recommended_opp is used.
|
|
*/
|
|
int devfreq_unregister_opp_notifier(struct device *dev, struct devfreq *devfreq)
|
|
{
|
|
struct srcu_notifier_head *nh;
|
|
int ret = 0;
|
|
|
|
rcu_read_lock();
|
|
nh = dev_pm_opp_get_notifier(dev);
|
|
if (IS_ERR(nh))
|
|
ret = PTR_ERR(nh);
|
|
rcu_read_unlock();
|
|
if (!ret)
|
|
ret = srcu_notifier_chain_unregister(nh, &devfreq->nb);
|
|
|
|
return ret;
|
|
}
|
|
|
|
MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
|
|
MODULE_DESCRIPTION("devfreq class support");
|
|
MODULE_LICENSE("GPL");
|