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authorChanwoo Choi <cw00.choi@samsung.com>2017-01-31 09:38:16 +0300
committerMyungJoo Ham <myungjoo.ham@samsung.com>2017-01-31 09:46:49 +0300
commitbcf23c79c4e46130701370af4383b61a3cba755c (patch)
treeca478a869ccc775a9215bb406b67bc81cd42c770 /drivers/devfreq
parentb0d75c08092f870825fbb766ac191faedd248918 (diff)
downloadlinux-bcf23c79c4e46130701370af4383b61a3cba755c.tar.xz
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 <cw00.choi@samsung.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Diffstat (limited to 'drivers/devfreq')
-rw-r--r--drivers/devfreq/devfreq.c31
-rw-r--r--drivers/devfreq/governor_passive.c1
2 files changed, 28 insertions, 4 deletions
diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index 8e5938c9c7d6..ade279d29f1e 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 9ef46e2592c4..93795b32dc09 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,
};