diff options
| author | Nishanth Menon | 2012-10-29 15:01:48 -0500 |
|---|---|---|
| committer | MyungJoo Ham | 2012-11-20 18:46:24 +0900 |
| commit | 50a5b33e0159f8783ef617cdb9d5fbb6a3955b6f (patch) | |
| tree | 0063869677d9da4bc78e4b32de852767e4cd15f0 | |
| parent | 0359d1afe4013d1a216908b6be4c6695a1db6fd6 (diff) | |
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>
| -rw-r--r-- | Documentation/ABI/testing/sysfs-class-devfreq | 7 | ||||
| -rw-r--r-- | drivers/devfreq/devfreq.c | 22 |
2 files changed, 29 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-class-devfreq b/Documentation/ABI/testing/sysfs-class-devfreq index 66876debca18..0ba6ea2f89d9 100644 --- a/Documentation/ABI/testing/sysfs-class-devfreq +++ b/Documentation/ABI/testing/sysfs-class-devfreq @@ -71,3 +71,10 @@ Description: the available frequencies of the corresponding devfreq object. This is a snapshot of available frequencies and not limited by the min/max frequency restrictions. + +What: /sys/class/devfreq/.../available_governors +Date: October 2012 +Contact: Nishanth Menon <nm@ti.com> +Description: + The /sys/class/devfreq/.../available_governors shows + currently available governors in the system. diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c index ff960f084c11..45e053e5b139 100644 --- a/drivers/devfreq/devfreq.c +++ b/drivers/devfreq/devfreq.c @@ -730,6 +730,27 @@ out: 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 ssize_t show_trans_table(struct device *dev, struct device_attribute *att 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), |