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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /drivers/devfreq/governor_userspace.c
parentInitial commit. (diff)
downloadlinux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz
linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip
Adding upstream version 5.10.209.upstream/5.10.209
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/devfreq/governor_userspace.c')
-rw-r--r--drivers/devfreq/governor_userspace.c156
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..8a9cf8220
--- /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 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->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 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->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(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 = 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");