PM / devfreq: Add sysfs node to expose available governors
Now that governor list can be variable, knowing the available governors
is useful to be able to select a governor using relevant sysfs node.
Cc: Rajagopal Venkat <rajagopal.venkat@linaro.org>
Cc: MyungJoo Ham <myungjoo.ham@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Kevin Hilman <khilman@ti.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Git-commit: 50a5b33e0159f8783ef617cdb9d5fbb6a3955b6f
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Change-Id: I2b1ec9b9897d94e2efd8dc2e6dfa00d3c91d9f70
Signed-off-by: Jeremy Gebben <jgebben@codeaurora.org>
diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index 649bd76..4452249 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -730,6 +730,27 @@
ret = count;
return ret;
}
+static ssize_t show_available_governors(struct device *d,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct devfreq_governor *tmp_governor;
+ ssize_t count = 0;
+
+ mutex_lock(&devfreq_list_lock);
+ list_for_each_entry(tmp_governor, &devfreq_governor_list, node)
+ count += scnprintf(&buf[count], (PAGE_SIZE - count - 2),
+ "%s ", tmp_governor->name);
+ mutex_unlock(&devfreq_list_lock);
+
+ /* Truncate the trailing space */
+ if (count)
+ count--;
+
+ count += sprintf(&buf[count], "\n");
+
+ return count;
+}
static ssize_t show_freq(struct device *dev,
struct device_attribute *attr, char *buf)
@@ -917,6 +938,7 @@
static struct device_attribute devfreq_attrs[] = {
__ATTR(governor, S_IRUGO | S_IWUSR, show_governor, store_governor),
+ __ATTR(available_governors, S_IRUGO, show_available_governors, NULL),
__ATTR(cur_freq, S_IRUGO, show_freq, NULL),
__ATTR(available_frequencies, S_IRUGO, show_available_freqs, NULL),
__ATTR(target_freq, S_IRUGO, show_target_freq, NULL),