Commit 4294a779 authored by Kamil Konieczny's avatar Kamil Konieczny Committed by MyungJoo Ham
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PM / devfreq: exynos-bus: Convert to use dev_pm_opp_set_rate() 



Reuse opp core code for setting bus clock and voltage. As a side
effect this allow usage of coupled regulators feature (required
for boards using Exynos5422/5800 SoCs) because dev_pm_opp_set_rate()
uses regulator_set_voltage_triplet() for setting regulator voltage
while the old code used regulator_set_voltage_tol() with fixed
tolerance. This patch also removes no longer needed parsing of DT
property "exynos,voltage-tolerance" (no Exynos devfreq DT node uses
it). After applying changes both functions exynos_bus_passive_target()
and exynos_bus_target() have the same code, so remove
exynos_bus_passive_target(). In exynos_bus_probe() replace it with
exynos_bus_target.

Signed-off-by: default avatarKamil Konieczny <k.konieczny@partner.samsung.com>
Acked-by: default avatarChanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: default avatarMyungJoo Ham <myungjoo.ham@samsung.com>
parent 2c2b20e0

drivers/devfreq/exynos-bus.c

+24 −106
Original line number Diff line number Diff line
@@ -22,7 +22,6 @@ 
#include <linux/slab.h>



#define DEFAULT_SATURATION_RATIO	40

#define DEFAULT_VOLTAGE_TOLERANCE	2



struct exynos_bus {

	struct device *dev;
@@ -34,9 +33,8 @@ struct exynos_bus { 


	unsigned long curr_freq;



	struct regulator *regulator;

	struct opp_table *opp_table;

	struct clk *clk;

	unsigned int voltage_tolerance;

	unsigned int ratio;

};
@@ -90,62 +88,29 @@ static int exynos_bus_get_event(struct exynos_bus *bus, 
}



/*

 * Must necessary function for devfreq simple-ondemand governor

 * devfreq function for both simple-ondemand and passive governor

 */

static int exynos_bus_target(struct device *dev, unsigned long *freq, u32 flags)

{

	struct exynos_bus *bus = dev_get_drvdata(dev);

	struct dev_pm_opp *new_opp;

	unsigned long old_freq, new_freq, new_volt, tol;

	int ret = 0;



	/* Get new opp-bus instance according to new bus clock */

	/* Get correct frequency for bus. */

	new_opp = devfreq_recommended_opp(dev, freq, flags);

	if (IS_ERR(new_opp)) {

		dev_err(dev, "failed to get recommended opp instance\n");

		return PTR_ERR(new_opp);

	}



	new_freq = dev_pm_opp_get_freq(new_opp);

	new_volt = dev_pm_opp_get_voltage(new_opp);

	dev_pm_opp_put(new_opp);



	old_freq = bus->curr_freq;



	if (old_freq == new_freq)

		return 0;

	tol = new_volt * bus->voltage_tolerance / 100;



	/* Change voltage and frequency according to new OPP level */

	mutex_lock(&bus->lock);

	ret = dev_pm_opp_set_rate(dev, *freq);

	if (!ret)

		bus->curr_freq = *freq;



	if (old_freq < new_freq) {

		ret = regulator_set_voltage_tol(bus->regulator, new_volt, tol);

		if (ret < 0) {

			dev_err(bus->dev, "failed to set voltage\n");

			goto out;

		}

	}



	ret = clk_set_rate(bus->clk, new_freq);

	if (ret < 0) {

		dev_err(dev, "failed to change clock of bus\n");

		clk_set_rate(bus->clk, old_freq);

		goto out;

	}



	if (old_freq > new_freq) {

		ret = regulator_set_voltage_tol(bus->regulator, new_volt, tol);

		if (ret < 0) {

			dev_err(bus->dev, "failed to set voltage\n");

			goto out;

		}

	}

	bus->curr_freq = new_freq;



	dev_dbg(dev, "Set the frequency of bus (%luHz -> %luHz, %luHz)\n",

			old_freq, new_freq, clk_get_rate(bus->clk));

out:

	mutex_unlock(&bus->lock);



	return ret;
@@ -193,54 +158,10 @@ static void exynos_bus_exit(struct device *dev) 


	dev_pm_opp_of_remove_table(dev);

	clk_disable_unprepare(bus->clk);

	if (bus->regulator)

		regulator_disable(bus->regulator);

	if (bus->opp_table) {

		dev_pm_opp_put_regulators(bus->opp_table);

		bus->opp_table = NULL;

	}



/*

 * Must necessary function for devfreq passive governor

 */

static int exynos_bus_passive_target(struct device *dev, unsigned long *freq,

					u32 flags)

{

	struct exynos_bus *bus = dev_get_drvdata(dev);

	struct dev_pm_opp *new_opp;

	unsigned long old_freq, new_freq;

	int ret = 0;



	/* Get new opp-bus instance according to new bus clock */

	new_opp = devfreq_recommended_opp(dev, freq, flags);

	if (IS_ERR(new_opp)) {

		dev_err(dev, "failed to get recommended opp instance\n");

		return PTR_ERR(new_opp);

	}



	new_freq = dev_pm_opp_get_freq(new_opp);

	dev_pm_opp_put(new_opp);



	old_freq = bus->curr_freq;



	if (old_freq == new_freq)

		return 0;



	/* Change the frequency according to new OPP level */

	mutex_lock(&bus->lock);



	ret = clk_set_rate(bus->clk, new_freq);

	if (ret < 0) {

		dev_err(dev, "failed to set the clock of bus\n");

		goto out;

	}



	*freq = new_freq;

	bus->curr_freq = new_freq;



	dev_dbg(dev, "Set the frequency of bus (%luHz -> %luHz, %luHz)\n",

			old_freq, new_freq, clk_get_rate(bus->clk));

out:

	mutex_unlock(&bus->lock);



	return ret;

}



static void exynos_bus_passive_exit(struct device *dev)
@@ -255,21 +176,19 @@ static int exynos_bus_parent_parse_of(struct device_node *np, 
					struct exynos_bus *bus)

{

	struct device *dev = bus->dev;

	struct opp_table *opp_table;

	const char *vdd = "vdd";

	int i, ret, count, size;



	/* Get the regulator to provide each bus with the power */

	bus->regulator = devm_regulator_get(dev, "vdd");

	if (IS_ERR(bus->regulator)) {

		dev_err(dev, "failed to get VDD regulator\n");

		return PTR_ERR(bus->regulator);

	}



	ret = regulator_enable(bus->regulator);

	if (ret < 0) {

		dev_err(dev, "failed to enable VDD regulator\n");

	opp_table = dev_pm_opp_set_regulators(dev, &vdd, 1);

	if (IS_ERR(opp_table)) {

		ret = PTR_ERR(opp_table);

		dev_err(dev, "failed to set regulators %d\n", ret);

		return ret;

	}



	bus->opp_table = opp_table;



	/*

	 * Get the devfreq-event devices to get the current utilization of

	 * buses. This raw data will be used in devfreq ondemand governor.
@@ -310,14 +229,11 @@ static int exynos_bus_parent_parse_of(struct device_node *np, 
	if (of_property_read_u32(np, "exynos,saturation-ratio", &bus->ratio))

		bus->ratio = DEFAULT_SATURATION_RATIO;



	if (of_property_read_u32(np, "exynos,voltage-tolerance",

					&bus->voltage_tolerance))

		bus->voltage_tolerance = DEFAULT_VOLTAGE_TOLERANCE;



	return 0;



err_regulator:

	regulator_disable(bus->regulator);

	dev_pm_opp_put_regulators(bus->opp_table);

	bus->opp_table = NULL;



	return ret;

}
@@ -468,7 +384,7 @@ static int exynos_bus_probe(struct platform_device *pdev) 
	goto out;

passive:

	/* Initialize the struct profile and governor data for passive device */

	profile->target = exynos_bus_passive_target;

	profile->target = exynos_bus_target;

	profile->exit = exynos_bus_passive_exit;



	/* Get the instance of parent devfreq device */
@@ -508,8 +424,10 @@ err: 
	dev_pm_opp_of_remove_table(dev);

	clk_disable_unprepare(bus->clk);

err_reg:

	if (!passive)

		regulator_disable(bus->regulator);

	if (!passive) {

		dev_pm_opp_put_regulators(bus->opp_table);

		bus->opp_table = NULL;

	}



	return ret;

}

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