// SPDX-License-Identifier: GPL-2.0-only /* *  linux/drivers/cpufreq/cpufreq_userspace.c * *  Copyright (C)  2001 Russell King *            (C)  2002 - 2004 Dominik Brodowski <linux@brodo.de> */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/cpufreq.h>#include <linux/init.h>#include <linux/module.h>#include <linux/mutex.h>#include <linux/slab.h> struct userspace_policy {	unsigned int is_managed;	unsigned int setspeed;	struct mutex mutex;}; /** * cpufreq_set - set the CPU frequency * @policy: pointer to policy struct where freq is being set * @freq: target frequency in kHz * * Sets the CPU frequency to freq. */static int cpufreq_set(struct cpufreq_policy *policy, unsigned int freq){	int ret = -EINVAL;	struct userspace_policy *userspace = policy->governor_data; 	pr_debug("cpufreq_set for cpu %u, freq %u kHz\n", policy->cpu, freq); 	mutex_lock(&userspace->mutex);	if (!userspace->is_managed)		goto err; 	userspace->setspeed = freq; 	ret = __cpufreq_driver_target(policy, freq, CPUFREQ_RELATION_L); err:	mutex_unlock(&userspace->mutex);	return ret;} static ssize_t show_speed(struct cpufreq_policy *policy, char *buf){	struct userspace_policy *userspace = policy->governor_data; 	return sprintf(buf, "%u\n", userspace->setspeed);} static int cpufreq_userspace_policy_init(struct cpufreq_policy *policy){	struct userspace_policy *userspace; 	userspace = kzalloc_obj(*userspace);	if (!userspace)		return -ENOMEM; 	mutex_init(&userspace->mutex); 	policy->governor_data = userspace;	return 0;} /* * Any routine that writes to the policy struct will hold the "rwsem" of * policy struct that means it is free to free "governor_data" here. */static void cpufreq_userspace_policy_exit(struct cpufreq_policy *policy){	kfree(policy->governor_data);	policy->governor_data = NULL;} static int cpufreq_userspace_policy_start(struct cpufreq_policy *policy){	struct userspace_policy *userspace = policy->governor_data; 	BUG_ON(!policy->cur);	pr_debug("started managing cpu %u\n", policy->cpu); 	mutex_lock(&userspace->mutex);	userspace->is_managed = 1;	userspace->setspeed = policy->cur;	mutex_unlock(&userspace->mutex);	return 0;} static void cpufreq_userspace_policy_stop(struct cpufreq_policy *policy){	struct userspace_policy *userspace = policy->governor_data; 	pr_debug("managing cpu %u stopped\n", policy->cpu); 	mutex_lock(&userspace->mutex);	userspace->is_managed = 0;	userspace->setspeed = 0;	mutex_unlock(&userspace->mutex);} static void cpufreq_userspace_policy_limits(struct cpufreq_policy *policy){	struct userspace_policy *userspace = policy->governor_data; 	mutex_lock(&userspace->mutex); 	pr_debug("limit event for cpu %u: %u - %u kHz, currently %u kHz, last set to %u kHz\n",		 policy->cpu, policy->min, policy->max, policy->cur, userspace->setspeed); 	if (policy->max < userspace->setspeed)		__cpufreq_driver_target(policy, policy->max,					CPUFREQ_RELATION_H);	else if (policy->min > userspace->setspeed)		__cpufreq_driver_target(policy, policy->min,					CPUFREQ_RELATION_L);	else		__cpufreq_driver_target(policy, userspace->setspeed,					CPUFREQ_RELATION_L); 	mutex_unlock(&userspace->mutex);} static struct cpufreq_governor cpufreq_gov_userspace = {	.name		= "userspace",	.init		= cpufreq_userspace_policy_init,	.exit		= cpufreq_userspace_policy_exit,	.start		= cpufreq_userspace_policy_start,	.stop		= cpufreq_userspace_policy_stop,	.limits		= cpufreq_userspace_policy_limits,	.store_setspeed	= cpufreq_set,	.show_setspeed	= show_speed,	.owner		= THIS_MODULE,	.flags		= CPUFREQ_GOV_STRICT_TARGET,}; MODULE_AUTHOR("Dominik Brodowski <linux@brodo.de>, "		"Russell King <rmk@arm.linux.org.uk>");MODULE_DESCRIPTION("CPUfreq policy governor 'userspace'");MODULE_LICENSE("GPL"); #ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACEstruct cpufreq_governor *cpufreq_default_governor(void){	return &cpufreq_gov_userspace;}#endif cpufreq_governor_init(cpufreq_gov_userspace);cpufreq_governor_exit(cpufreq_gov_userspace);