1 // SPDX-License-Identifier: GPL-2.0-only
3  *  linux/drivers/devfreq/governor_userspace.c
11 #include <linux/devfreq.h>
22 static int devfreq_userspace_func(struct devfreq *df, unsigned long *freq)  in devfreq_userspace_func()
24 	struct userspace_data *data = df->governor_data;  in devfreq_userspace_func()
26 	if (data->valid)  in devfreq_userspace_func()
27 		*freq = data->user_frequency;  in devfreq_userspace_func()
29 		*freq = df->previous_freq; /* No user freq specified yet */  in devfreq_userspace_func()
37 	struct devfreq *devfreq = to_devfreq(dev);  in set_freq_store()  local
42 	mutex_lock(&devfreq->lock);  in set_freq_store()
43 	data = devfreq->governor_data;  in set_freq_store()
46 	data->user_frequency = wanted;  in set_freq_store()
47 	data->valid = true;  in set_freq_store()
48 	err = update_devfreq(devfreq);  in set_freq_store()
51 	mutex_unlock(&devfreq->lock);  in set_freq_store()
58 	struct devfreq *devfreq = to_devfreq(dev);  in set_freq_show()  local
62 	mutex_lock(&devfreq->lock);  in set_freq_show()
63 	data = devfreq->governor_data;  in set_freq_show()
65 	if (data->valid)  in set_freq_show()
66 		err = sprintf(buf, "%lu\n", data->user_frequency);  in set_freq_show()
69 	mutex_unlock(&devfreq->lock);  in set_freq_show()
83 static int userspace_init(struct devfreq *devfreq)  in userspace_init()  argument
90 		err = -ENOMEM;  in userspace_init()
93 	data->valid = false;  in userspace_init()
94 	devfreq->governor_data = data;  in userspace_init()
96 	err = sysfs_create_group(&devfreq->dev.kobj, &dev_attr_group);  in userspace_init()
101 static void userspace_exit(struct devfreq *devfreq)  in userspace_exit()  argument
107 	if (devfreq->dev.kobj.sd)  in userspace_exit()
108 		sysfs_remove_group(&devfreq->dev.kobj, &dev_attr_group);  in userspace_exit()
110 	kfree(devfreq->governor_data);  in userspace_exit()
111 	devfreq->governor_data = NULL;  in userspace_exit()
114 static int devfreq_userspace_handler(struct devfreq *devfreq,  in devfreq_userspace_handler()  argument
115 			unsigned int event, void *data)  in devfreq_userspace_handler()  argument
119 	switch (event) {  in devfreq_userspace_handler()
121 		ret = userspace_init(devfreq);  in devfreq_userspace_handler()
124 		userspace_exit(devfreq);  in devfreq_userspace_handler()
156 MODULE_DESCRIPTION("DEVFREQ Userspace governor");