PM / devfreq: Restart previous governor if new governor fails to start
If the new governor fails to start, switch back to old governor so that the
devfreq state is not left in some weird limbo.
Change-Id: I7cf1e6ceb63d27ce08b2d17b97a9844d257464ce
Signed-off-by: Saravana Kannan <skannan@codeaurora.org>
diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index fd9ada6f..5b85b8d 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -925,7 +925,7 @@
struct devfreq *df = to_devfreq(dev);
int ret;
char str_governor[DEVFREQ_NAME_LEN + 1];
- struct devfreq_governor *governor;
+ const struct devfreq_governor *governor, *prev_gov;
ret = sscanf(buf, "%" __stringify(DEVFREQ_NAME_LEN) "s", str_governor);
if (ret != 1)
@@ -953,12 +953,21 @@
goto out;
}
}
+ prev_gov = df->governor;
df->governor = governor;
strncpy(df->governor_name, governor->name, DEVFREQ_NAME_LEN);
ret = df->governor->event_handler(df, DEVFREQ_GOV_START, NULL);
- if (ret)
+ if (ret) {
dev_warn(dev, "%s: Governor %s not started(%d)\n",
__func__, df->governor->name, ret);
+ if (prev_gov) {
+ df->governor = prev_gov;
+ strlcpy(df->governor_name, prev_gov->name,
+ DEVFREQ_NAME_LEN);
+ df->governor->event_handler(df, DEVFREQ_GOV_START,
+ NULL);
+ }
+ }
out:
mutex_unlock(&devfreq_list_lock);