diff options
Diffstat (limited to 'drivers/devfreq/devfreq.c')
| -rw-r--r-- | drivers/devfreq/devfreq.c | 31 |
1 files changed, 27 insertions, 4 deletions
diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c index 712592cef1a2..2eacfb4b905f 100644 --- a/drivers/devfreq/devfreq.c +++ b/drivers/devfreq/devfreq.c @@ -939,6 +939,9 @@ static ssize_t governor_store(struct device *dev, struct device_attribute *attr, if (df->governor == governor) { ret = 0; goto out; + } else if (df->governor->immutable || governor->immutable) { + ret = -EINVAL; + goto out; } if (df->governor) { @@ -968,13 +971,33 @@ static ssize_t available_governors_show(struct device *d, struct device_attribute *attr, char *buf) { - struct devfreq_governor *tmp_governor; + struct devfreq *df = to_devfreq(d); 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); + + /* + * The devfreq with immutable governor (e.g., passive) shows + * only own governor. + */ + if (df->governor->immutable) { + count = scnprintf(&buf[count], DEVFREQ_NAME_LEN, + "%s ", df->governor_name); + /* + * The devfreq device shows the registered governor except for + * immutable governors such as passive governor . + */ + } else { + struct devfreq_governor *governor; + + list_for_each_entry(governor, &devfreq_governor_list, node) { + if (governor->immutable) + continue; + count += scnprintf(&buf[count], (PAGE_SIZE - count - 2), + "%s ", governor->name); + } + } + mutex_unlock(&devfreq_list_lock); /* Truncate the trailing space */ |