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Release 4.14 drivers/devfreq/governor_userspace.c

Directory: drivers/devfreq
/*
 *  linux/drivers/devfreq/governor_userspace.c
 *
 *  Copyright (C) 2011 Samsung Electronics
 *      MyungJoo Ham <myungjoo.ham@samsung.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/slab.h>
#include <linux/device.h>
#include <linux/devfreq.h>
#include <linux/pm.h>
#include <linux/mutex.h>
#include <linux/module.h>
#include "governor.h"


struct userspace_data {
	
unsigned long user_frequency;
	
bool valid;
};


static int devfreq_userspace_func(struct devfreq *df, unsigned long *freq) { struct userspace_data *data = df->data; if (data->valid) { unsigned long adjusted_freq = data->user_frequency; if (df->max_freq && adjusted_freq > df->max_freq) adjusted_freq = df->max_freq; if (df->min_freq && adjusted_freq < df->min_freq) adjusted_freq = df->min_freq; *freq = adjusted_freq; } else { *freq = df->previous_freq; /* No user freq specified yet */ } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
MyungJoo Ham96100.00%2100.00%
Total96100.00%2100.00%


static ssize_t store_freq(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct devfreq *devfreq = to_devfreq(dev); struct userspace_data *data; unsigned long wanted; int err = 0; mutex_lock(&devfreq->lock); data = devfreq->data; sscanf(buf, "%lu", &wanted); data->user_frequency = wanted; data->valid = true; err = update_devfreq(devfreq); if (err == 0) err = count; mutex_unlock(&devfreq->lock); return err; }

Contributors

PersonTokensPropCommitsCommitProp
MyungJoo Ham112100.00%1100.00%
Total112100.00%1100.00%


static ssize_t show_freq(struct device *dev, struct device_attribute *attr, char *buf) { struct devfreq *devfreq = to_devfreq(dev); struct userspace_data *data; int err = 0; mutex_lock(&devfreq->lock); data = devfreq->data; if (data->valid) err = sprintf(buf, "%lu\n", data->user_frequency); else err = sprintf(buf, "undefined\n"); mutex_unlock(&devfreq->lock); return err; }

Contributors

PersonTokensPropCommitsCommitProp
MyungJoo Ham94100.00%1100.00%
Total94100.00%1100.00%

static DEVICE_ATTR(set_freq, 0644, show_freq, store_freq); static struct attribute *dev_entries[] = { &dev_attr_set_freq.attr, NULL, }; static const struct attribute_group dev_attr_group = { .name = "userspace", .attrs = dev_entries, };
static int userspace_init(struct devfreq *devfreq) { int err = 0; struct userspace_data *data = kzalloc(sizeof(struct userspace_data), GFP_KERNEL); if (!data) { err = -ENOMEM; goto out; } data->valid = false; devfreq->data = data; err = sysfs_create_group(&devfreq->dev.kobj, &dev_attr_group); out: return err; }

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PersonTokensPropCommitsCommitProp
MyungJoo Ham79100.00%1100.00%
Total79100.00%1100.00%


static void userspace_exit(struct devfreq *devfreq) { /* * Remove the sysfs entry, unless this is being called after * device_del(), which should have done this already via kobject_del(). */ if (devfreq->dev.kobj.sd) sysfs_remove_group(&devfreq->dev.kobj, &dev_attr_group); kfree(devfreq->data); devfreq->data = NULL; }

Contributors

PersonTokensPropCommitsCommitProp
MyungJoo Ham3777.08%150.00%
Chris Diamand1122.92%150.00%
Total48100.00%2100.00%


static int devfreq_userspace_handler(struct devfreq *devfreq, unsigned int event, void *data) { int ret = 0; switch (event) { case DEVFREQ_GOV_START: ret = userspace_init(devfreq); break; case DEVFREQ_GOV_STOP: userspace_exit(devfreq); break; default: break; } return ret; }

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PersonTokensPropCommitsCommitProp
Rajagopal Venkat55100.00%1100.00%
Total55100.00%1100.00%

static struct devfreq_governor devfreq_userspace = { .name = "userspace", .get_target_freq = devfreq_userspace_func, .event_handler = devfreq_userspace_handler, };
static int __init devfreq_userspace_init(void) { return devfreq_add_governor(&devfreq_userspace); }

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PersonTokensPropCommitsCommitProp
Nishanth Menon16100.00%1100.00%
Total16100.00%1100.00%

subsys_initcall(devfreq_userspace_init);
static void __exit devfreq_userspace_exit(void) { int ret; ret = devfreq_remove_governor(&devfreq_userspace); if (ret) pr_err("%s: failed remove governor %d\n", __func__, ret); return; }

Contributors

PersonTokensPropCommitsCommitProp
Nishanth Menon34100.00%1100.00%
Total34100.00%1100.00%

module_exit(devfreq_userspace_exit); MODULE_LICENSE("GPL");

Overall Contributors

PersonTokensPropCommitsCommitProp
MyungJoo Ham51278.65%222.22%
Nishanth Menon6910.60%333.33%
Rajagopal Venkat578.76%111.11%
Chris Diamand111.69%111.11%
Arvind Yadav10.15%111.11%
Chanwoo Choi10.15%111.11%
Total651100.00%9100.00%
Directory: drivers/devfreq
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