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authorLinus Torvalds <torvalds@linux-foundation.org>2011-10-25 15:18:39 +0200
committerLinus Torvalds <torvalds@linux-foundation.org>2011-10-25 15:18:39 +0200
commit7e0bb71e75020348bee523720a0c2f04cc72f540 (patch)
tree1a22d65bbce34e8cc0f82c543c9486ffb58332f7 /drivers/devfreq/governor_userspace.c
parentb9e2780d576a010d4aba1e69f247170bf3718d6b (diff)
parent0ab1e79b825a5cd8aeb3b34d89c9a89dea900056 (diff)
Merge branch 'pm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
* 'pm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (63 commits) PM / Clocks: Remove redundant NULL checks before kfree() PM / Documentation: Update docs about suspend and CPU hotplug ACPI / PM: Add Sony VGN-FW21E to nonvs blacklist. ARM: mach-shmobile: sh7372 A4R support (v4) ARM: mach-shmobile: sh7372 A3SP support (v4) PM / Sleep: Mark devices involved in wakeup signaling during suspend PM / Hibernate: Improve performance of LZO/plain hibernation, checksum image PM / Hibernate: Do not initialize static and extern variables to 0 PM / Freezer: Make fake_signal_wake_up() wake TASK_KILLABLE tasks too PM / Hibernate: Add resumedelay kernel param in addition to resumewait MAINTAINERS: Update linux-pm list address PM / ACPI: Blacklist Vaio VGN-FW520F machine known to require acpi_sleep=nonvs PM / ACPI: Blacklist Sony Vaio known to require acpi_sleep=nonvs PM / Hibernate: Add resumewait param to support MMC-like devices as resume file PM / Hibernate: Fix typo in a kerneldoc comment PM / Hibernate: Freeze kernel threads after preallocating memory PM: Update the policy on default wakeup settings PM / VT: Cleanup #if defined uglyness and fix compile error PM / Suspend: Off by one in pm_suspend() PM / Hibernate: Include storage keys in hibernation image on s390 ...
Diffstat (limited to 'drivers/devfreq/governor_userspace.c')
-rw-r--r--drivers/devfreq/governor_userspace.c116
1 files changed, 116 insertions, 0 deletions
diff --git a/drivers/devfreq/governor_userspace.c b/drivers/devfreq/governor_userspace.c
new file mode 100644
index 000000000000..4f8b563da782
--- /dev/null
+++ b/drivers/devfreq/governor_userspace.c
@@ -0,0 +1,116 @@
+/*
+ * linux/drivers/devfreq/governor_simpleondemand.c
+ *
+ * Copyright (C) 2011 Samsung Electronics
+ * MyungJoo Ham <myungjoo.ham@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/slab.h>
+#include <linux/device.h>
+#include <linux/devfreq.h>
+#include <linux/pm.h>
+#include <linux/mutex.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->data;
+
+ if (!data->valid)
+ *freq = df->previous_freq; /* No user freq specified yet */
+ else
+ *freq = data->user_frequency;
+ 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->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->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 struct attribute_group dev_attr_group = {
+ .name = "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->data = data;
+
+ err = sysfs_create_group(&devfreq->dev.kobj, &dev_attr_group);
+out:
+ return err;
+}
+
+static void userspace_exit(struct devfreq *devfreq)
+{
+ sysfs_remove_group(&devfreq->dev.kobj, &dev_attr_group);
+ kfree(devfreq->data);
+ devfreq->data = NULL;
+}
+
+const struct devfreq_governor devfreq_userspace = {
+ .name = "userspace",
+ .get_target_freq = devfreq_userspace_func,
+ .init = userspace_init,
+ .exit = userspace_exit,
+ .no_central_polling = true,
+};