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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/devfreq/governor_userspace.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | drivers/devfreq/governor_userspace.c | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/drivers/devfreq/governor_userspace.c b/drivers/devfreq/governor_userspace.c new file mode 100644 index 000000000..d69672cca --- /dev/null +++ b/drivers/devfreq/governor_userspace.c @@ -0,0 +1,156 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * linux/drivers/devfreq/governor_userspace.c + * + * Copyright (C) 2011 Samsung Electronics + * MyungJoo Ham <myungjoo.ham@samsung.com> + */ + +#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->governor_data; + + if (data->valid) + *freq = data->user_frequency; + else + *freq = df->previous_freq; /* No user freq specified yet */ + + return 0; +} + +static ssize_t set_freq_store(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->governor_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; +} + +static ssize_t set_freq_show(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->governor_data; + + if (data->valid) + err = sprintf(buf, "%lu\n", data->user_frequency); + else + err = sprintf(buf, "undefined\n"); + mutex_unlock(&devfreq->lock); + return err; +} + +static DEVICE_ATTR_RW(set_freq); +static struct attribute *dev_entries[] = { + &dev_attr_set_freq.attr, + NULL, +}; +static const struct attribute_group dev_attr_group = { + .name = DEVFREQ_GOV_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->governor_data = data; + + err = sysfs_create_group(&devfreq->dev.kobj, &dev_attr_group); +out: + return err; +} + +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->governor_data); + devfreq->governor_data = NULL; +} + +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; +} + +static struct devfreq_governor devfreq_userspace = { + .name = DEVFREQ_GOV_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); +} +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; +} +module_exit(devfreq_userspace_exit); +MODULE_LICENSE("GPL"); |