Merge tag 'pm-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management updates from Rafael Wysocki:
 "The majority of changes go into the cpufreq subsystem this time.

  To me, quite obviously, the biggest ticket item is the new "schedutil"
  governor.  Interestingly enough, it's the first new cpufreq governor
  since the beginning of the git era (except for some out-of-the-tree
  ones).

  There are two main differences between it and the existing governors.
  First, it uses the information provided by the scheduler directly for
  making its decisions, so it doesn't have to track anything by itself.
  Second, it can invoke drivers (supporting that feature) to adjust CPU
  performance right away without having to spawn work items to be
  executed in process context or similar.  Currently, the acpi-cpufreq
  driver is the only one supporting that mode of operation, but then it
  is used on a large number of systems.

  The "schedutil" governor as included here is very simple and mostly
  regarded as a foundation for future work on the integration of the
  scheduler with CPU power management (in fact, there is work in
  progress on top of it already).  Nevertheless it works and the
  preliminary results obtained with it are encouraging.

  There also is some consolidation of CPU frequency management for ARM
  platforms that can add their machine IDs the the new stub dt-platdev
  driver now and that will take care of creating the requisite platform
  device for cpufreq-dt, so it is not necessary to do that in platform
  code any more.  Several ARM platforms are switched over to using this
  generic mechanism.

  In addition to that, the intel_pstate driver is now going to respect
  CPU frequency limits set by the platform firmware (or a BMC) and
  provided via the ACPI _PPC object.

  The devfreq subsystem is getting a new "passive" governor for SoCs
  subsystems that will depend on somebody else to manage their voltage
  rails and its support for Samsung Exynos SoCs is consolidated.

  The rest is support for new hardware (Intel Broxton support in
  intel_idle for one example), bug fixes, optimizations and cleanups in
  a number of places.

  Specifics:

   - New cpufreq "schedutil" governor (making decisions based on CPU
     utilization information provided by the scheduler and capable of
     switching CPU frequencies right away if the underlying driver
     supports that) and support for fast frequency switching in the
     acpi-cpufreq driver (Rafael Wysocki)

   - Consolidation of CPU frequency management on ARM platforms allowing
     them to get rid of some platform-specific boilerplate code if they
     are going to use the cpufreq-dt driver (Viresh Kumar, Finley Xiao,
     Marc Gonzalez)

   - Support for ACPI _PPC and CPU frequency limits in the intel_pstate
     driver (Srinivas Pandruvada)

   - Fixes and cleanups in the cpufreq core and generic governor code
     (Rafael Wysocki, Sai Gurrappadi)

   - intel_pstate driver optimizations and cleanups (Rafael Wysocki,
     Philippe Longepe, Chen Yu, Joe Perches)

   - cpufreq powernv driver fixes and cleanups (Akshay Adiga, Shilpasri
     Bhat)

   - cpufreq qoriq driver fixes and cleanups (Jia Hongtao)

   - ACPI cpufreq driver cleanups (Viresh Kumar)

   - Assorted cpufreq driver updates (Ashwin Chaugule, Geliang Tang,
     Javier Martinez Canillas, Paul Gortmaker, Sudeep Holla)

   - Assorted cpufreq fixes and cleanups (Joe Perches, Arnd Bergmann)

   - Fixes and cleanups in the OPP (Operating Performance Points)
     framework, mostly related to OPP sharing, and reorganization of
     OF-dependent code in it (Viresh Kumar, Arnd Bergmann, Sudeep Holla)

   - New "passive" governor for devfreq (for SoC subsystems that will
     rely on someone else for the management of their power resources)
     and consolidation of devfreq support for Exynos platforms, coding
     style and typo fixes for devfreq (Chanwoo Choi, MyungJoo Ham)

   - PM core fixes and cleanups, mostly to make it work better with the
     generic power domains (genpd) framework, and updates for that
     framework (Ulf Hansson, Thierry Reding, Colin Ian King)

   - Intel Broxton support for the intel_idle driver (Len Brown)

   - cpuidle core optimization and fix (Daniel Lezcano, Dave Gerlach)

   - ARM cpuidle cleanups (Jisheng Zhang)

   - Intel Kabylake support for the RAPL power capping driver (Jacob
     Pan)

   - AVS (Adaptive Voltage Switching) rockchip-io driver update (Heiko
     Stuebner)

   - Updates for the cpupower tool (Arjun Sreedharan, Colin Ian King,
     Mattia Dongili, Thomas Renninger)"

* tag 'pm-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (112 commits)
  intel_pstate: Clean up get_target_pstate_use_performance()
  intel_pstate: Use sample.core_avg_perf in get_avg_pstate()
  intel_pstate: Clarify average performance computation
  intel_pstate: Avoid unnecessary synchronize_sched() during initialization
  cpufreq: schedutil: Make default depend on CONFIG_SMP
  cpufreq: powernv: del_timer_sync when global and local pstate are equal
  cpufreq: powernv: Move smp_call_function_any() out of irq safe block
  intel_pstate: Clean up intel_pstate_get()
  cpufreq: schedutil: Make it depend on CONFIG_SMP
  cpufreq: governor: Fix handling of special cases in dbs_update()
  PM / OPP: Move CONFIG_OF dependent code in a separate file
  cpufreq: intel_pstate: Ignore _PPC processing under HWP
  cpufreq: arm_big_little: use generic OPP functions for {init, free}_opp_table
  PM / OPP: add non-OF versions of dev_pm_opp_{cpumask_, }remove_table
  cpufreq: tango: Use generic platdev driver
  PM / OPP: pass cpumask by reference
  cpufreq: Fix GOV_LIMITS handling for the userspace governor
  cpupower: fix potential memory leak
  PM / devfreq: style/typo fixes
  PM / devfreq: exynos: Add the detailed correlation for Exynos5422 bus
  ..

1 files changed, 570 insertions, 0 deletions

diff --git a/drivers/devfreq/exynos-bus.c b/drivers/devfreq/exynos-bus.c
new file mode 100644
index 000000000000..2363d0a189b7
--- /dev/null
+++ b/drivers/devfreq/exynos-bus.c
@@ -0,0 +1,570 @@
+/*
+ * Generic Exynos Bus frequency driver with DEVFREQ Framework
+ *
+ * Copyright (c) 2016 Samsung Electronics Co., Ltd.
+ * Author : Chanwoo Choi <cw00.choi@samsung.com>
+ *
+ * This driver support Exynos Bus frequency feature by using
+ * DEVFREQ framework and is based on drivers/devfreq/exynos/exynos4_bus.c.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/clk.h>
+#include <linux/devfreq.h>
+#include <linux/devfreq-event.h>
+#include <linux/device.h>
+#include <linux/export.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/pm_opp.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+
+#define DEFAULT_SATURATION_RATIO	40
+#define DEFAULT_VOLTAGE_TOLERANCE	2
+
+struct exynos_bus {
+	struct device *dev;
+
+	struct devfreq *devfreq;
+	struct devfreq_event_dev **edev;
+	unsigned int edev_count;
+	struct mutex lock;
+
+	struct dev_pm_opp *curr_opp;
+
+	struct regulator *regulator;
+	struct clk *clk;
+	unsigned int voltage_tolerance;
+	unsigned int ratio;
+};
+
+/*
+ * Control the devfreq-event device to get the current state of bus
+ */
+#define exynos_bus_ops_edev(ops)				\
+static int exynos_bus_##ops(struct exynos_bus *bus)		\
+{								\
+	int i, ret;						\
+								\
+	for (i = 0; i < bus->edev_count; i++) {			\
+		if (!bus->edev[i])				\
+			continue;				\
+		ret = devfreq_event_##ops(bus->edev[i]);	\
+		if (ret < 0)					\
+			return ret;				\
+	}							\
+								\
+	return 0;						\
+}
+exynos_bus_ops_edev(enable_edev);
+exynos_bus_ops_edev(disable_edev);
+exynos_bus_ops_edev(set_event);
+
+static int exynos_bus_get_event(struct exynos_bus *bus,
+				struct devfreq_event_data *edata)
+{
+	struct devfreq_event_data event_data;
+	unsigned long load_count = 0, total_count = 0;
+	int i, ret = 0;
+
+	for (i = 0; i < bus->edev_count; i++) {
+		if (!bus->edev[i])
+			continue;
+
+		ret = devfreq_event_get_event(bus->edev[i], &event_data);
+		if (ret < 0)
+			return ret;
+
+		if (i == 0 || event_data.load_count > load_count) {
+			load_count = event_data.load_count;
+			total_count = event_data.total_count;
+		}
+	}
+
+	edata->load_count = load_count;
+	edata->total_count = total_count;
+
+	return ret;
+}
+
+/*
+ * Must necessary function for devfreq simple-ondemand 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, old_volt, new_volt, tol;
+	int ret = 0;
+
+	/* Get new opp-bus instance according to new bus clock */
+	rcu_read_lock();
+	new_opp = devfreq_recommended_opp(dev, freq, flags);
+	if (IS_ERR(new_opp)) {
+		dev_err(dev, "failed to get recommended opp instance\n");
+		rcu_read_unlock();
+		return PTR_ERR(new_opp);
+	}
+
+	new_freq = dev_pm_opp_get_freq(new_opp);
+	new_volt = dev_pm_opp_get_voltage(new_opp);
+	old_freq = dev_pm_opp_get_freq(bus->curr_opp);
+	old_volt = dev_pm_opp_get_voltage(bus->curr_opp);
+	rcu_read_unlock();
+
+	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);
+
+	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_opp = new_opp;
+
+	dev_dbg(dev, "Set the frequency of bus (%lukHz -> %lukHz)\n",
+			old_freq/1000, new_freq/1000);
+out:
+	mutex_unlock(&bus->lock);
+
+	return ret;
+}
+
+static int exynos_bus_get_dev_status(struct device *dev,
+				     struct devfreq_dev_status *stat)
+{
+	struct exynos_bus *bus = dev_get_drvdata(dev);
+	struct devfreq_event_data edata;
+	int ret;
+
+	rcu_read_lock();
+	stat->current_frequency = dev_pm_opp_get_freq(bus->curr_opp);
+	rcu_read_unlock();
+
+	ret = exynos_bus_get_event(bus, &edata);
+	if (ret < 0) {
+		stat->total_time = stat->busy_time = 0;
+		goto err;
+	}
+
+	stat->busy_time = (edata.load_count * 100) / bus->ratio;
+	stat->total_time = edata.total_count;
+
+	dev_dbg(dev, "Usage of devfreq-event : %lu/%lu\n", stat->busy_time,
+							stat->total_time);
+
+err:
+	ret = exynos_bus_set_event(bus);
+	if (ret < 0) {
+		dev_err(dev, "failed to set event to devfreq-event devices\n");
+		return ret;
+	}
+
+	return ret;
+}
+
+static void exynos_bus_exit(struct device *dev)
+{
+	struct exynos_bus *bus = dev_get_drvdata(dev);
+	int ret;
+
+	ret = exynos_bus_disable_edev(bus);
+	if (ret < 0)
+		dev_warn(dev, "failed to disable the devfreq-event devices\n");
+
+	if (bus->regulator)
+		regulator_disable(bus->regulator);
+
+	dev_pm_opp_of_remove_table(dev);
+	clk_disable_unprepare(bus->clk);
+}
+
+/*
+ * 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 */
+	rcu_read_lock();
+	new_opp = devfreq_recommended_opp(dev, freq, flags);
+	if (IS_ERR(new_opp)) {
+		dev_err(dev, "failed to get recommended opp instance\n");
+		rcu_read_unlock();
+		return PTR_ERR(new_opp);
+	}
+
+	new_freq = dev_pm_opp_get_freq(new_opp);
+	old_freq = dev_pm_opp_get_freq(bus->curr_opp);
+	rcu_read_unlock();
+
+	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_opp = new_opp;
+
+	dev_dbg(dev, "Set the frequency of bus (%lukHz -> %lukHz)\n",
+			old_freq/1000, new_freq/1000);
+out:
+	mutex_unlock(&bus->lock);
+
+	return ret;
+}
+
+static void exynos_bus_passive_exit(struct device *dev)
+{
+	struct exynos_bus *bus = dev_get_drvdata(dev);
+
+	dev_pm_opp_of_remove_table(dev);
+	clk_disable_unprepare(bus->clk);
+}
+
+static int exynos_bus_parent_parse_of(struct device_node *np,
+					struct exynos_bus *bus)
+{
+	struct device *dev = bus->dev;
+	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");
+		return ret;
+	}
+
+	/*
+	 * Get the devfreq-event devices to get the current utilization of
+	 * buses. This raw data will be used in devfreq ondemand governor.
+	 */
+	count = devfreq_event_get_edev_count(dev);
+	if (count < 0) {
+		dev_err(dev, "failed to get the count of devfreq-event dev\n");
+		ret = count;
+		goto err_regulator;
+	}
+	bus->edev_count = count;
+
+	size = sizeof(*bus->edev) * count;
+	bus->edev = devm_kzalloc(dev, size, GFP_KERNEL);
+	if (!bus->edev) {
+		ret = -ENOMEM;
+		goto err_regulator;
+	}
+
+	for (i = 0; i < count; i++) {
+		bus->edev[i] = devfreq_event_get_edev_by_phandle(dev, i);
+		if (IS_ERR(bus->edev[i])) {
+			ret = -EPROBE_DEFER;
+			goto err_regulator;
+		}
+	}
+
+	/*
+	 * Optionally, Get the saturation ratio according to Exynos SoC
+	 * When measuring the utilization of each AXI bus with devfreq-event
+	 * devices, the measured real cycle might be much lower than the
+	 * total cycle of bus during sampling rate. In result, the devfreq
+	 * simple-ondemand governor might not decide to change the current
+	 * frequency due to too utilization (= real cycle/total cycle).
+	 * So, this property is used to adjust the utilization when calculating
+	 * the busy_time in exynos_bus_get_dev_status().
+	 */
+	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);
+
+	return ret;
+}
+
+static int exynos_bus_parse_of(struct device_node *np,
+			      struct exynos_bus *bus)
+{
+	struct device *dev = bus->dev;
+	unsigned long rate;
+	int ret;
+
+	/* Get the clock to provide each bus with source clock */
+	bus->clk = devm_clk_get(dev, "bus");
+	if (IS_ERR(bus->clk)) {
+		dev_err(dev, "failed to get bus clock\n");
+		return PTR_ERR(bus->clk);
+	}
+
+	ret = clk_prepare_enable(bus->clk);
+	if (ret < 0) {
+		dev_err(dev, "failed to get enable clock\n");
+		return ret;
+	}
+
+	/* Get the freq and voltage from OPP table to scale the bus freq */
+	rcu_read_lock();
+	ret = dev_pm_opp_of_add_table(dev);
+	if (ret < 0) {
+		dev_err(dev, "failed to get OPP table\n");
+		rcu_read_unlock();
+		goto err_clk;
+	}
+
+	rate = clk_get_rate(bus->clk);
+	bus->curr_opp = devfreq_recommended_opp(dev, &rate, 0);
+	if (IS_ERR(bus->curr_opp)) {
+		dev_err(dev, "failed to find dev_pm_opp\n");
+		rcu_read_unlock();
+		ret = PTR_ERR(bus->curr_opp);
+		goto err_opp;
+	}
+	rcu_read_unlock();
+
+	return 0;
+
+err_opp:
+	dev_pm_opp_of_remove_table(dev);
+err_clk:
+	clk_disable_unprepare(bus->clk);
+
+	return ret;
+}
+
+static int exynos_bus_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+	struct devfreq_dev_profile *profile;
+	struct devfreq_simple_ondemand_data *ondemand_data;
+	struct devfreq_passive_data *passive_data;
+	struct devfreq *parent_devfreq;
+	struct exynos_bus *bus;
+	int ret, max_state;
+	unsigned long min_freq, max_freq;
+
+	if (!np) {
+		dev_err(dev, "failed to find devicetree node\n");
+		return -EINVAL;
+	}
+
+	bus = devm_kzalloc(&pdev->dev, sizeof(*bus), GFP_KERNEL);
+	if (!bus)
+		return -ENOMEM;
+	mutex_init(&bus->lock);
+	bus->dev = &pdev->dev;
+	platform_set_drvdata(pdev, bus);
+
+	/* Parse the device-tree to get the resource information */
+	ret = exynos_bus_parse_of(np, bus);
+	if (ret < 0)
+		goto err;
+
+	profile = devm_kzalloc(dev, sizeof(*profile), GFP_KERNEL);
+	if (!profile) {
+		ret = -ENOMEM;
+		goto err;
+	}
+
+	if (of_parse_phandle(dev->of_node, "devfreq", 0))
+		goto passive;
+	else
+		ret = exynos_bus_parent_parse_of(np, bus);
+
+	if (ret < 0)
+		goto err;
+
+	/* Initialize the struct profile and governor data for parent device */
+	profile->polling_ms = 50;
+	profile->target = exynos_bus_target;
+	profile->get_dev_status = exynos_bus_get_dev_status;
+	profile->exit = exynos_bus_exit;
+
+	ondemand_data = devm_kzalloc(dev, sizeof(*ondemand_data), GFP_KERNEL);
+	if (!ondemand_data) {
+		ret = -ENOMEM;
+		goto err;
+	}
+	ondemand_data->upthreshold = 40;
+	ondemand_data->downdifferential = 5;
+
+	/* Add devfreq device to monitor and handle the exynos bus */
+	bus->devfreq = devm_devfreq_add_device(dev, profile, "simple_ondemand",
+						ondemand_data);
+	if (IS_ERR(bus->devfreq)) {
+		dev_err(dev, "failed to add devfreq device\n");
+		ret = PTR_ERR(bus->devfreq);
+		goto err;
+	}
+
+	/* Register opp_notifier to catch the change of OPP  */
+	ret = devm_devfreq_register_opp_notifier(dev, bus->devfreq);
+	if (ret < 0) {
+		dev_err(dev, "failed to register opp notifier\n");
+		goto err;
+	}
+
+	/*
+	 * Enable devfreq-event to get raw data which is used to determine
+	 * current bus load.
+	 */
+	ret = exynos_bus_enable_edev(bus);
+	if (ret < 0) {
+		dev_err(dev, "failed to enable devfreq-event devices\n");
+		goto err;
+	}
+
+	ret = exynos_bus_set_event(bus);
+	if (ret < 0) {
+		dev_err(dev, "failed to set event to devfreq-event devices\n");
+		goto err;
+	}
+
+	goto out;
+passive:
+	/* Initialize the struct profile and governor data for passive device */
+	profile->target = exynos_bus_passive_target;
+	profile->exit = exynos_bus_passive_exit;
+
+	/* Get the instance of parent devfreq device */
+	parent_devfreq = devfreq_get_devfreq_by_phandle(dev, 0);
+	if (IS_ERR(parent_devfreq)) {
+		ret = -EPROBE_DEFER;
+		goto err;
+	}
+
+	passive_data = devm_kzalloc(dev, sizeof(*passive_data), GFP_KERNEL);
+	if (!passive_data) {
+		ret = -ENOMEM;
+		goto err;
+	}
+	passive_data->parent = parent_devfreq;
+
+	/* Add devfreq device for exynos bus with passive governor */
+	bus->devfreq = devm_devfreq_add_device(dev, profile, "passive",
+						passive_data);
+	if (IS_ERR(bus->devfreq)) {
+		dev_err(dev,
+			"failed to add devfreq dev with passive governor\n");
+		ret = -EPROBE_DEFER;
+		goto err;
+	}
+
+out:
+	max_state = bus->devfreq->profile->max_state;
+	min_freq = (bus->devfreq->profile->freq_table[0] / 1000);
+	max_freq = (bus->devfreq->profile->freq_table[max_state - 1] / 1000);
+	pr_info("exynos-bus: new bus device registered: %s (%6ld KHz ~ %6ld KHz)\n",
+			dev_name(dev), min_freq, max_freq);
+
+	return 0;
+
+err:
+	dev_pm_opp_of_remove_table(dev);
+	clk_disable_unprepare(bus->clk);
+
+	return ret;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int exynos_bus_resume(struct device *dev)
+{
+	struct exynos_bus *bus = dev_get_drvdata(dev);
+	int ret;
+
+	ret = exynos_bus_enable_edev(bus);
+	if (ret < 0) {
+		dev_err(dev, "failed to enable the devfreq-event devices\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int exynos_bus_suspend(struct device *dev)
+{
+	struct exynos_bus *bus = dev_get_drvdata(dev);
+	int ret;
+
+	ret = exynos_bus_disable_edev(bus);
+	if (ret < 0) {
+		dev_err(dev, "failed to disable the devfreq-event devices\n");
+		return ret;
+	}
+
+	return 0;
+}
+#endif
+
+static const struct dev_pm_ops exynos_bus_pm = {
+	SET_SYSTEM_SLEEP_PM_OPS(exynos_bus_suspend, exynos_bus_resume)
+};
+
+static const struct of_device_id exynos_bus_of_match[] = {
+	{ .compatible = "samsung,exynos-bus", },
+	{ /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, exynos_bus_of_match);
+
+static struct platform_driver exynos_bus_platdrv = {
+	.probe		= exynos_bus_probe,
+	.driver = {
+		.name	= "exynos-bus",
+		.pm	= &exynos_bus_pm,
+		.of_match_table = of_match_ptr(exynos_bus_of_match),
+	},
+};
+module_platform_driver(exynos_bus_platdrv);
+
+MODULE_DESCRIPTION("Generic Exynos Bus frequency driver");
+MODULE_AUTHOR("Chanwoo Choi <cw00.choi@samsung.com>");
+MODULE_LICENSE("GPL v2");