Commit 46cecc0b authored by Leonard Crestez's avatar Leonard Crestez Committed by Chanwoo Choi
Browse files

PM / devfreq: Introduce get_freq_range helper 



Moving handling of min/max freq to a single function and call it from
update_devfreq and for printing min/max freq values in sysfs.

This changes the behavior of out-of-range min_freq/max_freq: clamping
is now done at evaluation time. This means that if an out-of-range
constraint is imposed by sysfs and it later becomes valid then it will
be enforced.

Signed-off-by: default avatarLeonard Crestez <leonard.crestez@nxp.com>
Reviewed-by: default avatarMatthias Kaehlcke <mka@chromium.org>
Reviewed-by: default avatarChanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: default avatarChanwoo Choi <cw00.choi@samsung.com>
parent e7cc792d

drivers/devfreq/devfreq.c

+60 −48
Original line number Diff line number Diff line
@@ -98,6 +98,47 @@ static unsigned long find_available_max_freq(struct devfreq *devfreq) 
	return max_freq;

}



/**

 * get_freq_range() - Get the current freq range

 * @devfreq:	the devfreq instance

 * @min_freq:	the min frequency

 * @max_freq:	the max frequency

 *

 * This takes into consideration all constraints.

 */

static void get_freq_range(struct devfreq *devfreq,

			   unsigned long *min_freq,

			   unsigned long *max_freq)

{

	unsigned long *freq_table = devfreq->profile->freq_table;



	lockdep_assert_held(&devfreq->lock);



	/*

	 * Initialize minimum/maximum frequency from freq table.

	 * The devfreq drivers can initialize this in either ascending or

	 * descending order and devfreq core supports both.

	 */

	if (freq_table[0] < freq_table[devfreq->profile->max_state - 1]) {

		*min_freq = freq_table[0];

		*max_freq = freq_table[devfreq->profile->max_state - 1];

	} else {

		*min_freq = freq_table[devfreq->profile->max_state - 1];

		*max_freq = freq_table[0];

	}



	/* Apply constraints from sysfs */

	*min_freq = max(*min_freq, devfreq->min_freq);

	*max_freq = min(*max_freq, devfreq->max_freq);



	/* Apply constraints from OPP interface */

	*min_freq = max(*min_freq, devfreq->scaling_min_freq);

	*max_freq = min(*max_freq, devfreq->scaling_max_freq);



	if (*min_freq > *max_freq)

		*min_freq = *max_freq;

}



/**

 * devfreq_get_freq_level() - Lookup freq_table for the frequency

 * @devfreq:	the devfreq instance
@@ -351,16 +392,7 @@ int update_devfreq(struct devfreq *devfreq) 
	err = devfreq->governor->get_target_freq(devfreq, &freq);

	if (err)

		return err;



	/*

	 * Adjust the frequency with user freq, QoS and available freq.

	 *

	 * List from the highest priority

	 * max_freq

	 * min_freq

	 */

	max_freq = min(devfreq->scaling_max_freq, devfreq->max_freq);

	min_freq = max(devfreq->scaling_min_freq, devfreq->min_freq);

	get_freq_range(devfreq, &min_freq, &max_freq);



	if (freq < min_freq) {

		freq = min_freq;
@@ -1312,36 +1344,24 @@ static ssize_t min_freq_store(struct device *dev, struct device_attribute *attr, 
		return -EINVAL;



	mutex_lock(&df->lock);



	if (value) {

		if (value > df->max_freq) {

			ret = -EINVAL;

			goto unlock;

		}

	} else {

		unsigned long *freq_table = df->profile->freq_table;



		/* Get minimum frequency according to sorting order */

		if (freq_table[0] < freq_table[df->profile->max_state - 1])

			value = freq_table[0];

		else

			value = freq_table[df->profile->max_state - 1];

	}



	df->min_freq = value;

	update_devfreq(df);

	ret = count;

unlock:

	mutex_unlock(&df->lock);

	return ret;



	return count;

}



static ssize_t min_freq_show(struct device *dev, struct device_attribute *attr,

			     char *buf)

{

	struct devfreq *df = to_devfreq(dev);

	unsigned long min_freq, max_freq;



	mutex_lock(&df->lock);

	get_freq_range(df, &min_freq, &max_freq);

	mutex_unlock(&df->lock);



	return sprintf(buf, "%lu\n", max(df->scaling_min_freq, df->min_freq));

	return sprintf(buf, "%lu\n", min_freq);

}



static ssize_t max_freq_store(struct device *dev, struct device_attribute *attr,
@@ -1357,27 +1377,14 @@ static ssize_t max_freq_store(struct device *dev, struct device_attribute *attr, 


	mutex_lock(&df->lock);



	if (value) {

		if (value < df->min_freq) {

			ret = -EINVAL;

			goto unlock;

		}

	} else {

		unsigned long *freq_table = df->profile->freq_table;



		/* Get maximum frequency according to sorting order */

		if (freq_table[0] < freq_table[df->profile->max_state - 1])

			value = freq_table[df->profile->max_state - 1];

		else

			value = freq_table[0];

	}

	if (!value)

		value = ULONG_MAX;



	df->max_freq = value;

	update_devfreq(df);

	ret = count;

unlock:

	mutex_unlock(&df->lock);

	return ret;



	return count;

}

static DEVICE_ATTR_RW(min_freq);
@@ -1385,8 +1392,13 @@ static ssize_t max_freq_show(struct device *dev, struct device_attribute *attr, 
			     char *buf)

{

	struct devfreq *df = to_devfreq(dev);

	unsigned long min_freq, max_freq;



	mutex_lock(&df->lock);

	get_freq_range(df, &min_freq, &max_freq);

	mutex_unlock(&df->lock);



	return sprintf(buf, "%lu\n", min(df->scaling_max_freq, df->max_freq));

	return sprintf(buf, "%lu\n", max_freq);

}

static DEVICE_ATTR_RW(max_freq);

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