PM / devfreq: Do not show statistics if it's not ready.
authorMyungJoo Ham <myungjoo.ham@samsung.com>
Mon, 23 Nov 2015 06:45:36 +0000 (15:45 +0900)
committerMyungJoo Ham <myungjoo.ham@samsung.com>
Wed, 13 Jan 2016 08:30:33 +0000 (17:30 +0900)
Before this patch for a device without statistics support,

$ cat trans_stat
    From  :   To
          :   time(ms)
Total transitions : 0
$

After this patch applied for such a device,

$ cat trans_stat
Not Supported.
$

Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
drivers/devfreq/devfreq.c

index d36fa2db4d29aa8e871de8d4b56d03e0ccafdd5b..984c5e9e7bdd5bd72f66d0706661435f17b20b85 100644 (file)
@@ -1049,6 +1049,8 @@ static ssize_t trans_stat_show(struct device *dev,
        if (!devfreq->stop_polling &&
                        devfreq_update_status(devfreq, devfreq->previous_freq))
                return 0;
+       if (max_state == 0)
+               return sprintf(buf, "Not Supported.\n");
 
        len = sprintf(buf, "     From  :   To\n");
        len += sprintf(buf + len, "           :");