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From: MyungJoo Ham <myungjoo.ham@samsung.com>
To: 최찬우 <cw00.choi@samsung.com>
Cc: "linux-pm@vger.kernel.org" <linux-pm@vger.kernel.org>
Subject: [PATCH] PM / devfreq: Do not show statistics if it's not ready.
Date: Mon, 23 Nov 2015 06:53:21 +0000 (GMT)	[thread overview]
Message-ID: <670532133.123321448261601649.JavaMail.weblogic@epmlwas06a> (raw)


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 | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index fe3e3d1..1baa550 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -1048,6 +1048,8 @@ 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, "           :");
-- 
1.9.1


                 reply	other threads:[~2015-11-23  6:53 UTC|newest]

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