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Diffstat (limited to 'drivers/cpufreq/cpufreq_governor_attr_set.c')
-rw-r--r--drivers/cpufreq/cpufreq_governor_attr_set.c76
1 files changed, 76 insertions, 0 deletions
diff --git a/drivers/cpufreq/cpufreq_governor_attr_set.c b/drivers/cpufreq/cpufreq_governor_attr_set.c
new file mode 100644
index 0000000000..771770ea0e
--- /dev/null
+++ b/drivers/cpufreq/cpufreq_governor_attr_set.c
@@ -0,0 +1,76 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Abstract code for CPUFreq governor tunable sysfs attributes.
+ *
+ * Copyright (C) 2016, Intel Corporation
+ * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+ */
+
+#include "cpufreq_governor.h"
+
+static inline struct governor_attr *to_gov_attr(struct attribute *attr)
+{
+ return container_of(attr, struct governor_attr, attr);
+}
+
+static ssize_t governor_show(struct kobject *kobj, struct attribute *attr,
+ char *buf)
+{
+ struct governor_attr *gattr = to_gov_attr(attr);
+
+ return gattr->show(to_gov_attr_set(kobj), buf);
+}
+
+static ssize_t governor_store(struct kobject *kobj, struct attribute *attr,
+ const char *buf, size_t count)
+{
+ struct gov_attr_set *attr_set = to_gov_attr_set(kobj);
+ struct governor_attr *gattr = to_gov_attr(attr);
+ int ret;
+
+ mutex_lock(&attr_set->update_lock);
+ ret = attr_set->usage_count ? gattr->store(attr_set, buf, count) : -EBUSY;
+ mutex_unlock(&attr_set->update_lock);
+ return ret;
+}
+
+const struct sysfs_ops governor_sysfs_ops = {
+ .show = governor_show,
+ .store = governor_store,
+};
+EXPORT_SYMBOL_GPL(governor_sysfs_ops);
+
+void gov_attr_set_init(struct gov_attr_set *attr_set, struct list_head *list_node)
+{
+ INIT_LIST_HEAD(&attr_set->policy_list);
+ mutex_init(&attr_set->update_lock);
+ attr_set->usage_count = 1;
+ list_add(list_node, &attr_set->policy_list);
+}
+EXPORT_SYMBOL_GPL(gov_attr_set_init);
+
+void gov_attr_set_get(struct gov_attr_set *attr_set, struct list_head *list_node)
+{
+ mutex_lock(&attr_set->update_lock);
+ attr_set->usage_count++;
+ list_add(list_node, &attr_set->policy_list);
+ mutex_unlock(&attr_set->update_lock);
+}
+EXPORT_SYMBOL_GPL(gov_attr_set_get);
+
+unsigned int gov_attr_set_put(struct gov_attr_set *attr_set, struct list_head *list_node)
+{
+ unsigned int count;
+
+ mutex_lock(&attr_set->update_lock);
+ list_del(list_node);
+ count = --attr_set->usage_count;
+ mutex_unlock(&attr_set->update_lock);
+ if (count)
+ return count;
+
+ mutex_destroy(&attr_set->update_lock);
+ kobject_put(&attr_set->kobj);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(gov_attr_set_put);