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 <[email protected]> Cc: MyungJoo Ham <[email protected]> Cc: Kyungmin Park <[email protected]> Cc: "Rafael J. Wysocki" <[email protected]> Cc: Kevin Hilman <[email protected]> Cc: [email protected] Cc: [email protected] Signed-off-by: Nishanth Menon <[email protected]> --- Documentation/ABI/testing/sysfs-class-devfreq | 7 +++++++ drivers/devfreq/devfreq.c | 22 ++++++++++++++++++++++ 2 files changed, 29 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-class-devfreq b/Documentation/ABI/testing/sysfs-class-devfreq index 293f6b2..0daa83f 100644 --- a/Documentation/ABI/testing/sysfs-class-devfreq +++ b/Documentation/ABI/testing/sysfs-class-devfreq @@ -60,3 +60,10 @@ 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 <[email protected]> +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 8535f8c..9ed3ca5 100644 --- a/drivers/devfreq/devfreq.c +++ b/drivers/devfreq/devfreq.c @@ -666,6 +666,27 @@ 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) @@ -812,6 +833,7 @@ static ssize_t show_available_freqs(struct device *d, 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), -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
