From bcf23c79c4e46130701370af4383b61a3cba755c Mon Sep 17 00:00:00 2001 From: Chanwoo Choi Date: Tue, 31 Jan 2017 15:38:16 +0900 Subject: PM / devfreq: Fix available_governor sysfs The devfreq using passive governor is not able to change the governor. So, the user can not change the governor through 'available_governor' sysfs entry. Also, the devfreq which don't use the passive governor is not able to change to 'passive' governor on the fly. Fixes: 996133119f57 ("PM / devfreq: Add new passive governor") Cc: stable@vger.kernel.org Signed-off-by: Chanwoo Choi Signed-off-by: MyungJoo Ham --- drivers/devfreq/devfreq.c | 31 +++++++++++++++++++++++++++---- drivers/devfreq/governor_passive.c | 1 + 2 files changed, 28 insertions(+), 4 deletions(-) (limited to 'drivers/devfreq') diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c index 8e5938c..ade279d 100644 --- a/drivers/devfreq/devfreq.c +++ b/drivers/devfreq/devfreq.c @@ -940,6 +940,9 @@ 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) { @@ -969,13 +972,33 @@ 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 */ diff --git a/drivers/devfreq/governor_passive.c b/drivers/devfreq/governor_passive.c index 9ef46e2..93795b3 100644 --- a/drivers/devfreq/governor_passive.c +++ b/drivers/devfreq/governor_passive.c @@ -179,6 +179,7 @@ static int devfreq_passive_event_handler(struct devfreq *devfreq, static struct devfreq_governor devfreq_passive = { .name = "passive", + .immutable = 1, .get_target_freq = devfreq_passive_get_target_freq, .event_handler = devfreq_passive_event_handler, }; -- cgit v1.1