PM / devfreq: fix sscanf handling for writable sysfs entries

sscanf returns 0 when an invalid parameter like:
echo -n "a">min_freq
is attempted. Returning back the return result(0) will
cause the command not to return back to command
prompt.

Instead, just return -EINVAL when sscanf does not
return 1.

This is done for min_freq, max_freq and polling_interval

Signed-off-by: Nishanth Menon <nm@ti.com>
Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 3 insertions, 6 deletions

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index a42f69b34eb2..79a7343c28a6 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -496,12 +496,11 @@ static ssize_t store_polling_interval(struct device *dev,
 
         ret = sscanf(buf, "%u", &value);
         if (ret != 1)
-                goto out;
+                return -EINVAL;
 
         df->governor->event_handler(df, DEVFREQ_GOV_INTERVAL, &value);
         ret = count;
 
-out:
         return ret;
 }
 
@@ -515,7 +514,7 @@ static ssize_t store_min_freq(struct device *dev, struct device_attribute *attr,
 
         ret = sscanf(buf, "%lu", &value);
         if (ret != 1)
-                goto out;
+                return -EINVAL;
 
         mutex_lock(&df->lock);
         max = df->max_freq;
@@ -529,7 +528,6 @@ static ssize_t store_min_freq(struct device *dev, struct device_attribute *attr,
         ret = count;
 unlock:
         mutex_unlock(&df->lock);
-out:
         return ret;
 }
 
@@ -549,7 +547,7 @@ static ssize_t store_max_freq(struct device *dev, struct device_attribute *attr,
 
         ret = sscanf(buf, "%lu", &value);
         if (ret != 1)
-                goto out;
+                return -EINVAL;
 
         mutex_lock(&df->lock);
         min = df->min_freq;
@@ -563,7 +561,6 @@ static ssize_t store_max_freq(struct device *dev, struct device_attribute *attr,
         ret = count;
 unlock:
         mutex_unlock(&df->lock);
-out:
         return ret;
 }