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Diffstat (limited to 'kernel/drivers/devfreq/governor_powersave.c')
-rw-r--r--kernel/drivers/devfreq/governor_powersave.c64
1 files changed, 64 insertions, 0 deletions
diff --git a/kernel/drivers/devfreq/governor_powersave.c b/kernel/drivers/devfreq/governor_powersave.c
new file mode 100644
index 000000000..0c6bed567
--- /dev/null
+++ b/kernel/drivers/devfreq/governor_powersave.c
@@ -0,0 +1,64 @@
+/*
+ * linux/drivers/devfreq/governor_powersave.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/devfreq.h>
+#include <linux/module.h>
+#include "governor.h"
+
+static int devfreq_powersave_func(struct devfreq *df,
+ unsigned long *freq)
+{
+ /*
+ * target callback should be able to get ceiling value as
+ * said in devfreq.h
+ */
+ *freq = df->min_freq;
+ return 0;
+}
+
+static int devfreq_powersave_handler(struct devfreq *devfreq,
+ unsigned int event, void *data)
+{
+ int ret = 0;
+
+ if (event == DEVFREQ_GOV_START) {
+ mutex_lock(&devfreq->lock);
+ ret = update_devfreq(devfreq);
+ mutex_unlock(&devfreq->lock);
+ }
+
+ return ret;
+}
+
+static struct devfreq_governor devfreq_powersave = {
+ .name = "powersave",
+ .get_target_freq = devfreq_powersave_func,
+ .event_handler = devfreq_powersave_handler,
+};
+
+static int __init devfreq_powersave_init(void)
+{
+ return devfreq_add_governor(&devfreq_powersave);
+}
+subsys_initcall(devfreq_powersave_init);
+
+static void __exit devfreq_powersave_exit(void)
+{
+ int ret;
+
+ ret = devfreq_remove_governor(&devfreq_powersave);
+ if (ret)
+ pr_err("%s: failed remove governor %d\n", __func__, ret);
+
+ return;
+}
+module_exit(devfreq_powersave_exit);
+MODULE_LICENSE("GPL");