From 9005b65099ee4f14b6be691c4574612fe947531a Mon Sep 17 00:00:00 2001 From: MyungJoo Ham Date: Sun, 2 Oct 2011 00:19:28 +0200 Subject: PM / devfreq: Add common sysfs interfaces Device specific sysfs interface /sys/devices/.../power/devfreq_* - governor R: name of governor - cur_freq R: current frequency - polling_interval R: polling interval in ms given with devfreq profile W: update polling interval. - central_polling R: 1 if polling is managed by devfreq framework Signed-off-by: MyungJoo Ham Signed-off-by: Kyungmin Park Reviewed-by: Mike Turquette Acked-by: Kevin Hilman Signed-off-by: Rafael J. Wysocki -- Documentation/ABI/testing/sysfs-class-devfreq | 44 ++++++++++++++++ drivers/devfreq/devfreq.c | 69 ++++++++++++++++++++++++++ 2 files changed, 113 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-class-devfreq --- drivers/devfreq/devfreq.c | 69 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 69 insertions(+) (limited to 'drivers/devfreq') diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c index f3100b19f79..5d15b812377 100644 --- a/drivers/devfreq/devfreq.c +++ b/drivers/devfreq/devfreq.c @@ -437,6 +437,74 @@ int devfreq_remove_device(struct devfreq *devfreq) return 0; } +static ssize_t show_governor(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sprintf(buf, "%s\n", to_devfreq(dev)->governor->name); +} + +static ssize_t show_freq(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sprintf(buf, "%lu\n", to_devfreq(dev)->previous_freq); +} + +static ssize_t show_polling_interval(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sprintf(buf, "%d\n", to_devfreq(dev)->profile->polling_ms); +} + +static ssize_t store_polling_interval(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct devfreq *df = to_devfreq(dev); + unsigned int value; + int ret; + + ret = sscanf(buf, "%u", &value); + if (ret != 1) + goto out; + + mutex_lock(&df->lock); + df->profile->polling_ms = value; + df->next_polling = df->polling_jiffies + = msecs_to_jiffies(value); + mutex_unlock(&df->lock); + + ret = count; + + if (df->governor->no_central_polling) + goto out; + + mutex_lock(&devfreq_list_lock); + if (df->next_polling > 0 && !polling) { + polling = true; + queue_delayed_work(devfreq_wq, &devfreq_work, + df->next_polling); + } + mutex_unlock(&devfreq_list_lock); +out: + return ret; +} + +static ssize_t show_central_polling(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sprintf(buf, "%d\n", + !to_devfreq(dev)->governor->no_central_polling); +} + +static struct device_attribute devfreq_attrs[] = { + __ATTR(governor, S_IRUGO, show_governor, NULL), + __ATTR(cur_freq, S_IRUGO, show_freq, NULL), + __ATTR(central_polling, S_IRUGO, show_central_polling, NULL), + __ATTR(polling_interval, S_IRUGO | S_IWUSR, show_polling_interval, + store_polling_interval), + { }, +}; + /** * devfreq_start_polling() - Initialize data structure for devfreq framework and * start polling registered devfreq devices. @@ -461,6 +529,7 @@ static int __init devfreq_init(void) pr_err("%s: couldn't create class\n", __FILE__); return PTR_ERR(devfreq_class); } + devfreq_class->dev_attrs = devfreq_attrs; return 0; } subsys_initcall(devfreq_init); -- cgit v1.2.3-18-g5258