From: Jianqun Xu <jay.xu@rock-chips.com>
Date: Wed, 17 Aug 2016 08:43:57 +0000 (+0800)
Subject: PM / devfreq: add to show current load of device
X-Git-Tag: firefly_0821_release~1651
X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=0f75dc420951837e983a98a591055f58d4ff1f2a;p=firefly-linux-kernel-4.4.55.git

PM / devfreq: add to show current load of device

Calculate current load with busytime / totaltime from status,
also show the current frequency.

Change-Id: Ic310035db9c5478aa3d0b1e526b47c451fe09d23
Signed-off-by: Jianqun Xu <jay.xu@rock-chips.com>
---

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index b8fdf7a6608c..d73f1fec3fd7 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -1123,6 +1123,40 @@ static ssize_t trans_stat_show(struct device *dev,
 }
 static DEVICE_ATTR_RO(trans_stat);
 
+static ssize_t load_show(struct device *dev, struct device_attribute *attr,
+			 char *buf)
+{
+	int err;
+	struct devfreq *devfreq = to_devfreq(dev);
+	struct devfreq_dev_status stat = devfreq->last_status;
+	unsigned long freq;
+	ssize_t len;
+
+	err = devfreq_update_stats(devfreq);
+	if (err)
+		return err;
+
+	if (stat.total_time < stat.busy_time) {
+		err = devfreq_update_stats(devfreq);
+		if (err)
+			return err;
+	};
+
+	if (!stat.total_time)
+		return 0;
+
+	len = sprintf(buf, "%lu", stat.busy_time * 100 / stat.total_time);
+
+	if (devfreq->profile->get_cur_freq &&
+		!devfreq->profile->get_cur_freq(devfreq->dev.parent, &freq))
+			len += sprintf(buf + len, "@%luHz\n", freq);
+	else
+		len += sprintf(buf + len, "@%luHz\n", devfreq->previous_freq);
+
+	return len;
+}
+static DEVICE_ATTR_RO(load);
+
 static struct attribute *devfreq_attrs[] = {
 	&dev_attr_governor.attr,
 	&dev_attr_available_governors.attr,
@@ -1133,6 +1167,7 @@ static struct attribute *devfreq_attrs[] = {
 	&dev_attr_min_freq.attr,
 	&dev_attr_max_freq.attr,
 	&dev_attr_trans_stat.attr,
+	&dev_attr_load.attr,
 	NULL,
 };
 ATTRIBUTE_GROUPS(devfreq);