Merge tag 'pm-4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management updates from Rafael Wysocki:
 "There are no real big ticket items here this time.

  The most noticeable change is probably the relocation of the OPP
  (Operating Performance Points) framework to its own directory under
  drivers/ as it has grown big enough for that. Also Viresh is now going
  to maintain it and send pull requests for it to me, so you will see
  this change in the git history going forward (but still not right
  now).

  Another noticeable set of changes is the modifications of the PM core,
  the PCI subsystem and the ACPI PM domain to allow of more integration
  between system-wide suspend/resume and runtime PM. For now it's just a
  way to avoid resuming devices from runtime suspend unnecessarily
  during system suspend (if the driver sets a flag to indicate its
  readiness for that) and in the works is an analogous mechanism to
  allow devices to stay suspended after system resume.

  In addition to that, we have some changes related to supporting
  frequency-invariant CPU utilization metrics in the scheduler and in
  the schedutil cpufreq governor on ARM and changes to add support for
  device performance states to the generic power domains (genpd)
  framework.

  The rest is mostly fixes and cleanups of various sorts.

  Specifics:

   - Relocate the OPP (Operating Performance Points) framework to its
     own directory under drivers/ and add support for power domain
     performance states to it (Viresh Kumar).

   - Modify the PM core, the PCI bus type and the ACPI PM domain to
     support power management driver flags allowing device drivers to
     specify their capabilities and preferences regarding the handling
     of devices with enabled runtime PM during system suspend/resume and
     clean up that code somewhat (Rafael Wysocki, Ulf Hansson).

   - Add frequency-invariant accounting support to the task scheduler on
     ARM and ARM64 (Dietmar Eggemann).

   - Fix PM QoS device resume latency framework to prevent "no
     restriction" requests from overriding requests with specific
     requirements and drop the confusing PM_QOS_FLAG_REMOTE_WAKEUP
     device PM QoS flag (Rafael Wysocki).

   - Drop legacy class suspend/resume operations from the PM core and
     drop legacy bus type suspend and resume callbacks from ARM/locomo
     (Rafael Wysocki).

   - Add min/max frequency support to devfreq and clean it up somewhat
     (Chanwoo Choi).

   - Rework wakeup support in the generic power domains (genpd)
     framework and update some of its users accordingly (Geert
     Uytterhoeven).

   - Convert timers in the PM core to use timer_setup() (Kees Cook).

   - Add support for exposing the SLP_S0 (Low Power S0 Idle) residency
     counter based on the LPIT ACPI table on Intel platforms (Srinivas
     Pandruvada).

   - Add per-CPU PM QoS resume latency support to the ladder cpuidle
     governor (Ramesh Thomas).

   - Fix a deadlock between the wakeup notify handler and the notifier
     removal in the ACPI core (Ville Syrjälä).

   - Fix a cpufreq schedutil governor issue causing it to use stale
     cached frequency values sometimes (Viresh Kumar).

   - Fix an issue in the system suspend core support code causing wakeup
     events detection to fail in some cases (Rajat Jain).

   - Fix the generic power domains (genpd) framework to prevent the PM
     core from using the direct-complete optimization with it as that is
     guaranteed to fail (Ulf Hansson).

   - Fix a minor issue in the cpuidle core and clean it up a bit (Gaurav
     Jindal, Nicholas Piggin).

   - Fix and clean up the intel_idle and ARM cpuidle drivers (Jason
     Baron, Len Brown, Leo Yan).

   - Fix a couple of minor issues in the OPP framework and clean it up
     (Arvind Yadav, Fabio Estevam, Sudeep Holla, Tobias Jordan).

   - Fix and clean up some cpufreq drivers and fix a minor issue in the
     cpufreq statistics code (Arvind Yadav, Bhumika Goyal, Fabio
     Estevam, Gautham Shenoy, Gustavo Silva, Marek Szyprowski, Masahiro
     Yamada, Robert Jarzmik, Zumeng Chen).

   - Fix minor issues in the system suspend and hibernation core, in
     power management documentation and in the AVS (Adaptive Voltage
     Scaling) framework (Helge Deller, Himanshu Jha, Joe Perches, Rafael
     Wysocki).

   - Fix some issues in the cpupower utility and document that Shuah
     Khan is going to maintain it going forward (Prarit Bhargava, Shuah
     Khan)"

* tag 'pm-4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (88 commits)
  tools/power/cpupower: add libcpupower.so.0.0.1 to .gitignore
  tools/power/cpupower: Add 64 bit library detection
  intel_idle: Graceful probe failure when MWAIT is disabled
  cpufreq: schedutil: Reset cached_raw_freq when not in sync with next_freq
  freezer: Fix typo in freezable_schedule_timeout() comment
  PM / s2idle: Clear the events_check_enabled flag
  cpufreq: stats: Handle the case when trans_table goes beyond PAGE_SIZE
  cpufreq: arm_big_little: make cpufreq_arm_bL_ops structures const
  cpufreq: arm_big_little: make function arguments and structure pointer const
  cpuidle: Avoid assignment in if () argument
  cpuidle: Clean up cpuidle_enable_device() error handling a bit
  ACPI / PM: Fix acpi_pm_notifier_lock vs flush_workqueue() deadlock
  PM / Domains: Fix genpd to deal with drivers returning 1 from ->prepare()
  cpuidle: ladder: Add per CPU PM QoS resume latency support
  PM / QoS: Fix device resume latency framework
  PM / domains: Rework governor code to be more consistent
  PM / Domains: Remove gpd_dev_ops.active_wakeup() callback
  soc: rockchip: power-domain: Use GENPD_FLAG_ACTIVE_WAKEUP
  soc: mediatek: Use GENPD_FLAG_ACTIVE_WAKEUP
  ARM: shmobile: pm-rmobile: Use GENPD_FLAG_ACTIVE_WAKEUP
  ...

1 files changed, 1880 insertions, 0 deletions

diff --git a/drivers/opp/core.c b/drivers/opp/core.c
new file mode 100644
index 000000000000..92fa94a6dcc1
--- /dev/null
+++ b/drivers/opp/core.c
@@ -0,0 +1,1880 @@
+/*
+ * Generic OPP Interface
+ *
+ * Copyright (C) 2009-2010 Texas Instruments Incorporated.
+ *	Nishanth Menon
+ *	Romit Dasgupta
+ *	Kevin Hilman
+ *
+ * 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.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/clk.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/device.h>
+#include <linux/export.h>
+#include <linux/pm_domain.h>
+#include <linux/regulator/consumer.h>
+
+#include "opp.h"
+
+/*
+ * The root of the list of all opp-tables. All opp_table structures branch off
+ * from here, with each opp_table containing the list of opps it supports in
+ * various states of availability.
+ */
+LIST_HEAD(opp_tables);
+/* Lock to allow exclusive modification to the device and opp lists */
+DEFINE_MUTEX(opp_table_lock);
+
+static void dev_pm_opp_get(struct dev_pm_opp *opp);
+
+static struct opp_device *_find_opp_dev(const struct device *dev,
+					struct opp_table *opp_table)
+{
+	struct opp_device *opp_dev;
+
+	list_for_each_entry(opp_dev, &opp_table->dev_list, node)
+		if (opp_dev->dev == dev)
+			return opp_dev;
+
+	return NULL;
+}
+
+static struct opp_table *_find_opp_table_unlocked(struct device *dev)
+{
+	struct opp_table *opp_table;
+
+	list_for_each_entry(opp_table, &opp_tables, node) {
+		if (_find_opp_dev(dev, opp_table)) {
+			_get_opp_table_kref(opp_table);
+
+			return opp_table;
+		}
+	}
+
+	return ERR_PTR(-ENODEV);
+}
+
+/**
+ * _find_opp_table() - find opp_table struct using device pointer
+ * @dev:	device pointer used to lookup OPP table
+ *
+ * Search OPP table for one containing matching device.
+ *
+ * Return: pointer to 'struct opp_table' if found, otherwise -ENODEV or
+ * -EINVAL based on type of error.
+ *
+ * The callers must call dev_pm_opp_put_opp_table() after the table is used.
+ */
+struct opp_table *_find_opp_table(struct device *dev)
+{
+	struct opp_table *opp_table;
+
+	if (IS_ERR_OR_NULL(dev)) {
+		pr_err("%s: Invalid parameters\n", __func__);
+		return ERR_PTR(-EINVAL);
+	}
+
+	mutex_lock(&opp_table_lock);
+	opp_table = _find_opp_table_unlocked(dev);
+	mutex_unlock(&opp_table_lock);
+
+	return opp_table;
+}
+
+/**
+ * dev_pm_opp_get_voltage() - Gets the voltage corresponding to an opp
+ * @opp:	opp for which voltage has to be returned for
+ *
+ * Return: voltage in micro volt corresponding to the opp, else
+ * return 0
+ *
+ * This is useful only for devices with single power supply.
+ */
+unsigned long dev_pm_opp_get_voltage(struct dev_pm_opp *opp)
+{
+	if (IS_ERR_OR_NULL(opp)) {
+		pr_err("%s: Invalid parameters\n", __func__);
+		return 0;
+	}
+
+	return opp->supplies[0].u_volt;
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_get_voltage);
+
+/**
+ * dev_pm_opp_get_freq() - Gets the frequency corresponding to an available opp
+ * @opp:	opp for which frequency has to be returned for
+ *
+ * Return: frequency in hertz corresponding to the opp, else
+ * return 0
+ */
+unsigned long dev_pm_opp_get_freq(struct dev_pm_opp *opp)
+{
+	if (IS_ERR_OR_NULL(opp) || !opp->available) {
+		pr_err("%s: Invalid parameters\n", __func__);
+		return 0;
+	}
+
+	return opp->rate;
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_get_freq);
+
+/**
+ * dev_pm_opp_is_turbo() - Returns if opp is turbo OPP or not
+ * @opp: opp for which turbo mode is being verified
+ *
+ * Turbo OPPs are not for normal use, and can be enabled (under certain
+ * conditions) for short duration of times to finish high throughput work
+ * quickly. Running on them for longer times may overheat the chip.
+ *
+ * Return: true if opp is turbo opp, else false.
+ */
+bool dev_pm_opp_is_turbo(struct dev_pm_opp *opp)
+{
+	if (IS_ERR_OR_NULL(opp) || !opp->available) {
+		pr_err("%s: Invalid parameters\n", __func__);
+		return false;
+	}
+
+	return opp->turbo;
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_is_turbo);
+
+/**
+ * dev_pm_opp_get_max_clock_latency() - Get max clock latency in nanoseconds
+ * @dev:	device for which we do this operation
+ *
+ * Return: This function returns the max clock latency in nanoseconds.
+ */
+unsigned long dev_pm_opp_get_max_clock_latency(struct device *dev)
+{
+	struct opp_table *opp_table;
+	unsigned long clock_latency_ns;
+
+	opp_table = _find_opp_table(dev);
+	if (IS_ERR(opp_table))
+		return 0;
+
+	clock_latency_ns = opp_table->clock_latency_ns_max;
+
+	dev_pm_opp_put_opp_table(opp_table);
+
+	return clock_latency_ns;
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_get_max_clock_latency);
+
+/**
+ * dev_pm_opp_get_max_volt_latency() - Get max voltage latency in nanoseconds
+ * @dev: device for which we do this operation
+ *
+ * Return: This function returns the max voltage latency in nanoseconds.
+ */
+unsigned long dev_pm_opp_get_max_volt_latency(struct device *dev)
+{
+	struct opp_table *opp_table;
+	struct dev_pm_opp *opp;
+	struct regulator *reg;
+	unsigned long latency_ns = 0;
+	int ret, i, count;
+	struct {
+		unsigned long min;
+		unsigned long max;
+	} *uV;
+
+	opp_table = _find_opp_table(dev);
+	if (IS_ERR(opp_table))
+		return 0;
+
+	count = opp_table->regulator_count;
+
+	/* Regulator may not be required for the device */
+	if (!count)
+		goto put_opp_table;
+
+	uV = kmalloc_array(count, sizeof(*uV), GFP_KERNEL);
+	if (!uV)
+		goto put_opp_table;
+
+	mutex_lock(&opp_table->lock);
+
+	for (i = 0; i < count; i++) {
+		uV[i].min = ~0;
+		uV[i].max = 0;
+
+		list_for_each_entry(opp, &opp_table->opp_list, node) {
+			if (!opp->available)
+				continue;
+
+			if (opp->supplies[i].u_volt_min < uV[i].min)
+				uV[i].min = opp->supplies[i].u_volt_min;
+			if (opp->supplies[i].u_volt_max > uV[i].max)
+				uV[i].max = opp->supplies[i].u_volt_max;
+		}
+	}
+
+	mutex_unlock(&opp_table->lock);
+
+	/*
+	 * The caller needs to ensure that opp_table (and hence the regulator)
+	 * isn't freed, while we are executing this routine.
+	 */
+	for (i = 0; i < count; i++) {
+		reg = opp_table->regulators[i];
+		ret = regulator_set_voltage_time(reg, uV[i].min, uV[i].max);
+		if (ret > 0)
+			latency_ns += ret * 1000;
+	}
+
+	kfree(uV);
+put_opp_table:
+	dev_pm_opp_put_opp_table(opp_table);
+
+	return latency_ns;
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_get_max_volt_latency);
+
+/**
+ * dev_pm_opp_get_max_transition_latency() - Get max transition latency in
+ *					     nanoseconds
+ * @dev: device for which we do this operation
+ *
+ * Return: This function returns the max transition latency, in nanoseconds, to
+ * switch from one OPP to other.
+ */
+unsigned long dev_pm_opp_get_max_transition_latency(struct device *dev)
+{
+	return dev_pm_opp_get_max_volt_latency(dev) +
+		dev_pm_opp_get_max_clock_latency(dev);
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_get_max_transition_latency);
+
+/**
+ * dev_pm_opp_get_suspend_opp_freq() - Get frequency of suspend opp in Hz
+ * @dev:	device for which we do this operation
+ *
+ * Return: This function returns the frequency of the OPP marked as suspend_opp
+ * if one is available, else returns 0;
+ */
+unsigned long dev_pm_opp_get_suspend_opp_freq(struct device *dev)
+{
+	struct opp_table *opp_table;
+	unsigned long freq = 0;
+
+	opp_table = _find_opp_table(dev);
+	if (IS_ERR(opp_table))
+		return 0;
+
+	if (opp_table->suspend_opp && opp_table->suspend_opp->available)
+		freq = dev_pm_opp_get_freq(opp_table->suspend_opp);
+
+	dev_pm_opp_put_opp_table(opp_table);
+
+	return freq;
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_get_suspend_opp_freq);
+
+/**
+ * dev_pm_opp_get_opp_count() - Get number of opps available in the opp table
+ * @dev:	device for which we do this operation
+ *
+ * Return: This function returns the number of available opps if there are any,
+ * else returns 0 if none or the corresponding error value.
+ */
+int dev_pm_opp_get_opp_count(struct device *dev)
+{
+	struct opp_table *opp_table;
+	struct dev_pm_opp *temp_opp;
+	int count = 0;
+
+	opp_table = _find_opp_table(dev);
+	if (IS_ERR(opp_table)) {
+		count = PTR_ERR(opp_table);
+		dev_dbg(dev, "%s: OPP table not found (%d)\n",
+			__func__, count);
+		return count;
+	}
+
+	mutex_lock(&opp_table->lock);
+
+	list_for_each_entry(temp_opp, &opp_table->opp_list, node) {
+		if (temp_opp->available)
+			count++;
+	}
+
+	mutex_unlock(&opp_table->lock);
+	dev_pm_opp_put_opp_table(opp_table);
+
+	return count;
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_get_opp_count);
+
+/**
+ * dev_pm_opp_find_freq_exact() - search for an exact frequency
+ * @dev:		device for which we do this operation
+ * @freq:		frequency to search for
+ * @available:		true/false - match for available opp
+ *
+ * Return: Searches for exact match in the opp table and returns pointer to the
+ * matching opp if found, else returns ERR_PTR in case of error and should
+ * be handled using IS_ERR. Error return values can be:
+ * EINVAL:	for bad pointer
+ * ERANGE:	no match found for search
+ * ENODEV:	if device not found in list of registered devices
+ *
+ * Note: available is a modifier for the search. if available=true, then the
+ * match is for exact matching frequency and is available in the stored OPP
+ * table. if false, the match is for exact frequency which is not available.
+ *
+ * This provides a mechanism to enable an opp which is not available currently
+ * or the opposite as well.
+ *
+ * The callers are required to call dev_pm_opp_put() for the returned OPP after
+ * use.
+ */
+struct dev_pm_opp *dev_pm_opp_find_freq_exact(struct device *dev,
+					      unsigned long freq,
+					      bool available)
+{
+	struct opp_table *opp_table;
+	struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ERANGE);
+
+	opp_table = _find_opp_table(dev);
+	if (IS_ERR(opp_table)) {
+		int r = PTR_ERR(opp_table);
+
+		dev_err(dev, "%s: OPP table not found (%d)\n", __func__, r);
+		return ERR_PTR(r);
+	}
+
+	mutex_lock(&opp_table->lock);
+
+	list_for_each_entry(temp_opp, &opp_table->opp_list, node) {
+		if (temp_opp->available == available &&
+				temp_opp->rate == freq) {
+			opp = temp_opp;
+
+			/* Increment the reference count of OPP */
+			dev_pm_opp_get(opp);
+			break;
+		}
+	}
+
+	mutex_unlock(&opp_table->lock);
+	dev_pm_opp_put_opp_table(opp_table);
+
+	return opp;
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_find_freq_exact);
+
+static noinline struct dev_pm_opp *_find_freq_ceil(struct opp_table *opp_table,
+						   unsigned long *freq)
+{
+	struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ERANGE);
+
+	mutex_lock(&opp_table->lock);
+
+	list_for_each_entry(temp_opp, &opp_table->opp_list, node) {
+		if (temp_opp->available && temp_opp->rate >= *freq) {
+			opp = temp_opp;
+			*freq = opp->rate;
+
+			/* Increment the reference count of OPP */
+			dev_pm_opp_get(opp);
+			break;
+		}
+	}
+
+	mutex_unlock(&opp_table->lock);
+
+	return opp;
+}
+
+/**
+ * dev_pm_opp_find_freq_ceil() - Search for an rounded ceil freq
+ * @dev:	device for which we do this operation
+ * @freq:	Start frequency
+ *
+ * Search for the matching ceil *available* OPP from a starting freq
+ * for a device.
+ *
+ * Return: matching *opp and refreshes *freq accordingly, else returns
+ * ERR_PTR in case of error and should be handled using IS_ERR. Error return
+ * values can be:
+ * EINVAL:	for bad pointer
+ * ERANGE:	no match found for search
+ * ENODEV:	if device not found in list of registered devices
+ *
+ * The callers are required to call dev_pm_opp_put() for the returned OPP after
+ * use.
+ */
+struct dev_pm_opp *dev_pm_opp_find_freq_ceil(struct device *dev,
+					     unsigned long *freq)
+{
+	struct opp_table *opp_table;
+	struct dev_pm_opp *opp;
+
+	if (!dev || !freq) {
+		dev_err(dev, "%s: Invalid argument freq=%p\n", __func__, freq);
+		return ERR_PTR(-EINVAL);
+	}
+
+	opp_table = _find_opp_table(dev);
+	if (IS_ERR(opp_table))
+		return ERR_CAST(opp_table);
+
+	opp = _find_freq_ceil(opp_table, freq);
+
+	dev_pm_opp_put_opp_table(opp_table);
+
+	return opp;
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_find_freq_ceil);
+
+/**
+ * dev_pm_opp_find_freq_floor() - Search for a rounded floor freq
+ * @dev:	device for which we do this operation
+ * @freq:	Start frequency
+ *
+ * Search for the matching floor *available* OPP from a starting freq
+ * for a device.
+ *
+ * Return: matching *opp and refreshes *freq accordingly, else returns
+ * ERR_PTR in case of error and should be handled using IS_ERR. Error return
+ * values can be:
+ * EINVAL:	for bad pointer
+ * ERANGE:	no match found for search
+ * ENODEV:	if device not found in list of registered devices
+ *
+ * The callers are required to call dev_pm_opp_put() for the returned OPP after
+ * use.
+ */
+struct dev_pm_opp *dev_pm_opp_find_freq_floor(struct device *dev,
+					      unsigned long *freq)
+{
+	struct opp_table *opp_table;
+	struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ERANGE);
+
+	if (!dev || !freq) {
+		dev_err(dev, "%s: Invalid argument freq=%p\n", __func__, freq);
+		return ERR_PTR(-EINVAL);
+	}
+
+	opp_table = _find_opp_table(dev);
+	if (IS_ERR(opp_table))
+		return ERR_CAST(opp_table);
+
+	mutex_lock(&opp_table->lock);
+
+	list_for_each_entry(temp_opp, &opp_table->opp_list, node) {
+		if (temp_opp->available) {
+			/* go to the next node, before choosing prev */
+			if (temp_opp->rate > *freq)
+				break;
+			else
+				opp = temp_opp;
+		}
+	}
+
+	/* Increment the reference count of OPP */
+	if (!IS_ERR(opp))
+		dev_pm_opp_get(opp);
+	mutex_unlock(&opp_table->lock);
+	dev_pm_opp_put_opp_table(opp_table);
+
+	if (!IS_ERR(opp))
+		*freq = opp->rate;
+
+	return opp;
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_find_freq_floor);
+
+static int _set_opp_voltage(struct device *dev, struct regulator *reg,
+			    struct dev_pm_opp_supply *supply)
+{
+	int ret;
+
+	/* Regulator not available for device */
+	if (IS_ERR(reg)) {
+		dev_dbg(dev, "%s: regulator not available: %ld\n", __func__,
+			PTR_ERR(reg));
+		return 0;
+	}
+
+	dev_dbg(dev, "%s: voltages (mV): %lu %lu %lu\n", __func__,
+		supply->u_volt_min, supply->u_volt, supply->u_volt_max);
+
+	ret = regulator_set_voltage_triplet(reg, supply->u_volt_min,
+					    supply->u_volt, supply->u_volt_max);
+	if (ret)
+		dev_err(dev, "%s: failed to set voltage (%lu %lu %lu mV): %d\n",
+			__func__, supply->u_volt_min, supply->u_volt,
+			supply->u_volt_max, ret);
+
+	return ret;
+}
+
+static inline int
+_generic_set_opp_clk_only(struct device *dev, struct clk *clk,
+			  unsigned long old_freq, unsigned long freq)
+{
+	int ret;
+
+	ret = clk_set_rate(clk, freq);
+	if (ret) {
+		dev_err(dev, "%s: failed to set clock rate: %d\n", __func__,
+			ret);
+	}
+
+	return ret;
+}
+
+static inline int
+_generic_set_opp_domain(struct device *dev, struct clk *clk,
+			unsigned long old_freq, unsigned long freq,
+			unsigned int old_pstate, unsigned int new_pstate)
+{
+	int ret;
+
+	/* Scaling up? Scale domain performance state before frequency */
+	if (freq > old_freq) {
+		ret = dev_pm_genpd_set_performance_state(dev, new_pstate);
+		if (ret)
+			return ret;
+	}
+
+	ret = _generic_set_opp_clk_only(dev, clk, old_freq, freq);
+	if (ret)
+		goto restore_domain_state;
+
+	/* Scaling down? Scale domain performance state after frequency */
+	if (freq < old_freq) {
+		ret = dev_pm_genpd_set_performance_state(dev, new_pstate);
+		if (ret)
+			goto restore_freq;
+	}
+
+	return 0;
+
+restore_freq:
+	if (_generic_set_opp_clk_only(dev, clk, freq, old_freq))
+		dev_err(dev, "%s: failed to restore old-freq (%lu Hz)\n",
+			__func__, old_freq);
+restore_domain_state:
+	if (freq > old_freq)
+		dev_pm_genpd_set_performance_state(dev, old_pstate);
+
+	return ret;
+}
+
+static int _generic_set_opp_regulator(const struct opp_table *opp_table,
+				      struct device *dev,
+				      unsigned long old_freq,
+				      unsigned long freq,
+				      struct dev_pm_opp_supply *old_supply,
+				      struct dev_pm_opp_supply *new_supply)
+{
+	struct regulator *reg = opp_table->regulators[0];
+	int ret;
+
+	/* This function only supports single regulator per device */
+	if (WARN_ON(opp_table->regulator_count > 1)) {
+		dev_err(dev, "multiple regulators are not supported\n");
+		return -EINVAL;
+	}
+
+	/* Scaling up? Scale voltage before frequency */
+	if (freq > old_freq) {
+		ret = _set_opp_voltage(dev, reg, new_supply);
+		if (ret)
+			goto restore_voltage;
+	}
+
+	/* Change frequency */
+	ret = _generic_set_opp_clk_only(dev, opp_table->clk, old_freq, freq);
+	if (ret)
+		goto restore_voltage;
+
+	/* Scaling down? Scale voltage after frequency */
+	if (freq < old_freq) {
+		ret = _set_opp_voltage(dev, reg, new_supply);
+		if (ret)
+			goto restore_freq;
+	}
+
+	return 0;
+
+restore_freq:
+	if (_generic_set_opp_clk_only(dev, opp_table->clk, freq, old_freq))
+		dev_err(dev, "%s: failed to restore old-freq (%lu Hz)\n",
+			__func__, old_freq);
+restore_voltage:
+	/* This shouldn't harm even if the voltages weren't updated earlier */
+	if (old_supply)
+		_set_opp_voltage(dev, reg, old_supply);
+
+	return ret;
+}
+
+/**
+ * dev_pm_opp_set_rate() - Configure new OPP based on frequency
+ * @dev:	 device for which we do this operation
+ * @target_freq: frequency to achieve
+ *
+ * This configures the power-supplies and clock source to the levels specified
+ * by the OPP corresponding to the target_freq.
+ */
+int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq)
+{
+	struct opp_table *opp_table;
+	unsigned long freq, old_freq;
+	struct dev_pm_opp *old_opp, *opp;
+	struct clk *clk;
+	int ret, size;
+
+	if (unlikely(!target_freq)) {
+		dev_err(dev, "%s: Invalid target frequency %lu\n", __func__,
+			target_freq);
+		return -EINVAL;
+	}
+
+	opp_table = _find_opp_table(dev);
+	if (IS_ERR(opp_table)) {
+		dev_err(dev, "%s: device opp doesn't exist\n", __func__);
+		return PTR_ERR(opp_table);
+	}
+
+	clk = opp_table->clk;
+	if (IS_ERR(clk)) {
+		dev_err(dev, "%s: No clock available for the device\n",
+			__func__);
+		ret = PTR_ERR(clk);
+		goto put_opp_table;
+	}
+
+	freq = clk_round_rate(clk, target_freq);
+	if ((long)freq <= 0)
+		freq = target_freq;
+
+	old_freq = clk_get_rate(clk);
+
+	/* Return early if nothing to do */
+	if (old_freq == freq) {
+		dev_dbg(dev, "%s: old/new frequencies (%lu Hz) are same, nothing to do\n",
+			__func__, freq);
+		ret = 0;
+		goto put_opp_table;
+	}
+
+	old_opp = _find_freq_ceil(opp_table, &old_freq);
+	if (IS_ERR(old_opp)) {
+		dev_err(dev, "%s: failed to find current OPP for freq %lu (%ld)\n",
+			__func__, old_freq, PTR_ERR(old_opp));
+	}
+
+	opp = _find_freq_ceil(opp_table, &freq);
+	if (IS_ERR(opp)) {
+		ret = PTR_ERR(opp);
+		dev_err(dev, "%s: failed to find OPP for freq %lu (%d)\n",
+			__func__, freq, ret);
+		goto put_old_opp;
+	}
+
+	dev_dbg(dev, "%s: switching OPP: %lu Hz --> %lu Hz\n", __func__,
+		old_freq, freq);
+
+	/* Only frequency scaling */
+	if (!opp_table->regulators) {
+		/*
+		 * We don't support devices with both regulator and
+		 * domain performance-state for now.
+		 */
+		if (opp_table->genpd_performance_state)
+			ret = _generic_set_opp_domain(dev, clk, old_freq, freq,
+						      IS_ERR(old_opp) ? 0 : old_opp->pstate,
+						      opp->pstate);
+		else
+			ret = _generic_set_opp_clk_only(dev, clk, old_freq, freq);
+	} else if (!opp_table->set_opp) {
+		ret = _generic_set_opp_regulator(opp_table, dev, old_freq, freq,
+						 IS_ERR(old_opp) ? NULL : old_opp->supplies,
+						 opp->supplies);
+	} else {
+		struct dev_pm_set_opp_data *data;
+
+		data = opp_table->set_opp_data;
+		data->regulators = opp_table->regulators;
+		data->regulator_count = opp_table->regulator_count;
+		data->clk = clk;
+		data->dev = dev;
+
+		data->old_opp.rate = old_freq;
+		size = sizeof(*opp->supplies) * opp_table->regulator_count;
+		if (IS_ERR(old_opp))
+			memset(data->old_opp.supplies, 0, size);
+		else
+			memcpy(data->old_opp.supplies, old_opp->supplies, size);
+
+		data->new_opp.rate = freq;
+		memcpy(data->new_opp.supplies, opp->supplies, size);
+
+		ret = opp_table->set_opp(data);
+	}
+
+	dev_pm_opp_put(opp);
+put_old_opp:
+	if (!IS_ERR(old_opp))
+		dev_pm_opp_put(old_opp);
+put_opp_table:
+	dev_pm_opp_put_opp_table(opp_table);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_set_rate);
+
+/* OPP-dev Helpers */
+static void _remove_opp_dev(struct opp_device *opp_dev,
+			    struct opp_table *opp_table)
+{
+	opp_debug_unregister(opp_dev, opp_table);
+	list_del(&opp_dev->node);
+	kfree(opp_dev);
+}
+
+struct opp_device *_add_opp_dev(const struct device *dev,
+				struct opp_table *opp_table)
+{
+	struct opp_device *opp_dev;
+	int ret;
+
+	opp_dev = kzalloc(sizeof(*opp_dev), GFP_KERNEL);
+	if (!opp_dev)
+		return NULL;
+
+	/* Initialize opp-dev */
+	opp_dev->dev = dev;
+	list_add(&opp_dev->node, &opp_table->dev_list);
+
+	/* Create debugfs entries for the opp_table */
+	ret = opp_debug_register(opp_dev, opp_table);
+	if (ret)
+		dev_err(dev, "%s: Failed to register opp debugfs (%d)\n",
+			__func__, ret);
+
+	return opp_dev;
+}
+
+static struct opp_table *_allocate_opp_table(struct device *dev)
+{
+	struct opp_table *opp_table;
+	struct opp_device *opp_dev;
+	int ret;
+
+	/*
+	 * Allocate a new OPP table. In the infrequent case where a new
+	 * device is needed to be added, we pay this penalty.
+	 */
+	opp_table = kzalloc(sizeof(*opp_table), GFP_KERNEL);
+	if (!opp_table)
+		return NULL;
+
+	INIT_LIST_HEAD(&opp_table->dev_list);
+
+	opp_dev = _add_opp_dev(dev, opp_table);
+	if (!opp_dev) {
+		kfree(opp_table);
+		return NULL;
+	}
+
+	_of_init_opp_table(opp_table, dev);
+
+	/* Find clk for the device */
+	opp_table->clk = clk_get(dev, NULL);
+	if (IS_ERR(opp_table->clk)) {
+		ret = PTR_ERR(opp_table->clk);
+		if (ret != -EPROBE_DEFER)
+			dev_dbg(dev, "%s: Couldn't find clock: %d\n", __func__,
+				ret);
+	}
+
+	BLOCKING_INIT_NOTIFIER_HEAD(&opp_table->head);
+	INIT_LIST_HEAD(&opp_table->opp_list);
+	mutex_init(&opp_table->lock);
+	kref_init(&opp_table->kref);
+
+	/* Secure the device table modification */
+	list_add(&opp_table->node, &opp_tables);
+	return opp_table;
+}
+
+void _get_opp_table_kref(struct opp_table *opp_table)
+{
+	kref_get(&opp_table->kref);
+}
+
+struct opp_table *dev_pm_opp_get_opp_table(struct device *dev)
+{
+	struct opp_table *opp_table;
+
+	/* Hold our table modification lock here */
+	mutex_lock(&opp_table_lock);
+
+	opp_table = _find_opp_table_unlocked(dev);
+	if (!IS_ERR(opp_table))
+		goto unlock;
+
+	opp_table = _allocate_opp_table(dev);
+
+unlock:
+	mutex_unlock(&opp_table_lock);
+
+	return opp_table;
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_get_opp_table);
+
+static void _opp_table_kref_release(struct kref *kref)
+{
+	struct opp_table *opp_table = container_of(kref, struct opp_table, kref);
+	struct opp_device *opp_dev;
+
+	/* Release clk */
+	if (!IS_ERR(opp_table->clk))
+		clk_put(opp_table->clk);
+
+	opp_dev = list_first_entry(&opp_table->dev_list, struct opp_device,
+				   node);
+
+	_remove_opp_dev(opp_dev, opp_table);
+
+	/* dev_list must be empty now */
+	WARN_ON(!list_empty(&opp_table->dev_list));
+
+	mutex_destroy(&opp_table->lock);
+	list_del(&opp_table->node);
+	kfree(opp_table);
+
+	mutex_unlock(&opp_table_lock);
+}
+
+void dev_pm_opp_put_opp_table(struct opp_table *opp_table)
+{
+	kref_put_mutex(&opp_table->kref, _opp_table_kref_release,
+		       &opp_table_lock);
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_put_opp_table);
+
+void _opp_free(struct dev_pm_opp *opp)
+{
+	kfree(opp);
+}
+
+static void _opp_kref_release(struct kref *kref)
+{
+	struct dev_pm_opp *opp = container_of(kref, struct dev_pm_opp, kref);
+	struct opp_table *opp_table = opp->opp_table;
+
+	/*
+	 * Notify the changes in the availability of the operable
+	 * frequency/voltage list.
+	 */
+	blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_REMOVE, opp);
+	opp_debug_remove_one(opp);
+	list_del(&opp->node);
+	kfree(opp);
+
+	mutex_unlock(&opp_table->lock);
+	dev_pm_opp_put_opp_table(opp_table);
+}
+
+static void dev_pm_opp_get(struct dev_pm_opp *opp)
+{
+	kref_get(&opp->kref);
+}
+
+void dev_pm_opp_put(struct dev_pm_opp *opp)
+{
+	kref_put_mutex(&opp->kref, _opp_kref_release, &opp->opp_table->lock);
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_put);
+
+/**
+ * dev_pm_opp_remove()  - Remove an OPP from OPP table
+ * @dev:	device for which we do this operation
+ * @freq:	OPP to remove with matching 'freq'
+ *
+ * This function removes an opp from the opp table.
+ */
+void dev_pm_opp_remove(struct device *dev, unsigned long freq)
+{
+	struct dev_pm_opp *opp;
+	struct opp_table *opp_table;
+	bool found = false;
+
+	opp_table = _find_opp_table(dev);
+	if (IS_ERR(opp_table))
+		return;
+
+	mutex_lock(&opp_table->lock);
+
+	list_for_each_entry(opp, &opp_table->opp_list, node) {
+		if (opp->rate == freq) {
+			found = true;
+			break;
+		}
+	}
+
+	mutex_unlock(&opp_table->lock);
+
+	if (found) {
+		dev_pm_opp_put(opp);
+	} else {
+		dev_warn(dev, "%s: Couldn't find OPP with freq: %lu\n",
+			 __func__, freq);
+	}
+
+	dev_pm_opp_put_opp_table(opp_table);
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_remove);
+
+struct dev_pm_opp *_opp_allocate(struct opp_table *table)
+{
+	struct dev_pm_opp *opp;
+	int count, supply_size;
+
+	/* Allocate space for at least one supply */
+	count = table->regulator_count ? table->regulator_count : 1;
+	supply_size = sizeof(*opp->supplies) * count;
+
+	/* allocate new OPP node and supplies structures */
+	opp = kzalloc(sizeof(*opp) + supply_size, GFP_KERNEL);
+	if (!opp)
+		return NULL;
+
+	/* Put the supplies at the end of the OPP structure as an empty array */
+	opp->supplies = (struct dev_pm_opp_supply *)(opp + 1);
+	INIT_LIST_HEAD(&opp->node);
+
+	return opp;
+}
+
+static bool _opp_supported_by_regulators(struct dev_pm_opp *opp,
+					 struct opp_table *opp_table)
+{
+	struct regulator *reg;
+	int i;
+
+	for (i = 0; i < opp_table->regulator_count; i++) {
+		reg = opp_table->regulators[i];
+
+		if (!regulator_is_supported_voltage(reg,
+					opp->supplies[i].u_volt_min,
+					opp->supplies[i].u_volt_max)) {
+			pr_warn("%s: OPP minuV: %lu maxuV: %lu, not supported by regulator\n",
+				__func__, opp->supplies[i].u_volt_min,
+				opp->supplies[i].u_volt_max);
+			return false;
+		}
+	}
+
+	return true;
+}
+
+/*
+ * Returns:
+ * 0: On success. And appropriate error message for duplicate OPPs.
+ * -EBUSY: For OPP with same freq/volt and is available. The callers of
+ *  _opp_add() must return 0 if they receive -EBUSY from it. This is to make
+ *  sure we don't print error messages unnecessarily if different parts of
+ *  kernel try to initialize the OPP table.
+ * -EEXIST: For OPP with same freq but different volt or is unavailable. This
+ *  should be considered an error by the callers of _opp_add().
+ */
+int _opp_add(struct device *dev, struct dev_pm_opp *new_opp,
+	     struct opp_table *opp_table)
+{
+	struct dev_pm_opp *opp;
+	struct list_head *head;
+	int ret;
+
+	/*
+	 * Insert new OPP in order of increasing frequency and discard if
+	 * already present.
+	 *
+	 * Need to use &opp_table->opp_list in the condition part of the 'for'
+	 * loop, don't replace it with head otherwise it will become an infinite
+	 * loop.
+	 */
+	mutex_lock(&opp_table->lock);
+	head = &opp_table->opp_list;
+
+	list_for_each_entry(opp, &opp_table->opp_list, node) {
+		if (new_opp->rate > opp->rate) {
+			head = &opp->node;
+			continue;
+		}
+
+		if (new_opp->rate < opp->rate)
+			break;
+
+		/* Duplicate OPPs */
+		dev_warn(dev, "%s: duplicate OPPs detected. Existing: freq: %lu, volt: %lu, enabled: %d. New: freq: %lu, volt: %lu, enabled: %d\n",
+			 __func__, opp->rate, opp->supplies[0].u_volt,
+			 opp->available, new_opp->rate,
+			 new_opp->supplies[0].u_volt, new_opp->available);
+
+		/* Should we compare voltages for all regulators here ? */
+		ret = opp->available &&
+		      new_opp->supplies[0].u_volt == opp->supplies[0].u_volt ? -EBUSY : -EEXIST;
+
+		mutex_unlock(&opp_table->lock);
+		return ret;
+	}
+
+	if (opp_table->get_pstate)
+		new_opp->pstate = opp_table->get_pstate(dev, new_opp->rate);
+
+	list_add(&new_opp->node, head);
+	mutex_unlock(&opp_table->lock);
+
+	new_opp->opp_table = opp_table;
+	kref_init(&new_opp->kref);
+
+	/* Get a reference to the OPP table */
+	_get_opp_table_kref(opp_table);
+
+	ret = opp_debug_create_one(new_opp, opp_table);
+	if (ret)
+		dev_err(dev, "%s: Failed to register opp to debugfs (%d)\n",
+			__func__, ret);
+
+	if (!_opp_supported_by_regulators(new_opp, opp_table)) {
+		new_opp->available = false;
+		dev_warn(dev, "%s: OPP not supported by regulators (%lu)\n",
+			 __func__, new_opp->rate);
+	}
+
+	return 0;
+}
+
+/**
+ * _opp_add_v1() - Allocate a OPP based on v1 bindings.
+ * @opp_table:	OPP table
+ * @dev:	device for which we do this operation
+ * @freq:	Frequency in Hz for this OPP
+ * @u_volt:	Voltage in uVolts for this OPP
+ * @dynamic:	Dynamically added OPPs.
+ *
+ * This function adds an opp definition to the opp table and returns status.
+ * The opp is made available by default and it can be controlled using
+ * dev_pm_opp_enable/disable functions and may be removed by dev_pm_opp_remove.
+ *
+ * NOTE: "dynamic" parameter impacts OPPs added by the dev_pm_opp_of_add_table
+ * and freed by dev_pm_opp_of_remove_table.
+ *
+ * Return:
+ * 0		On success OR
+ *		Duplicate OPPs (both freq and volt are same) and opp->available
+ * -EEXIST	Freq are same and volt are different OR
+ *		Duplicate OPPs (both freq and volt are same) and !opp->available
+ * -ENOMEM	Memory allocation failure
+ */
+int _opp_add_v1(struct opp_table *opp_table, struct device *dev,
+		unsigned long freq, long u_volt, bool dynamic)
+{
+	struct dev_pm_opp *new_opp;
+	unsigned long tol;
+	int ret;
+
+	new_opp = _opp_allocate(opp_table);
+	if (!new_opp)
+		return -ENOMEM;
+
+	/* populate the opp table */
+	new_opp->rate = freq;
+	tol = u_volt * opp_table->voltage_tolerance_v1 / 100;
+	new_opp->supplies[0].u_volt = u_volt;
+	new_opp->supplies[0].u_volt_min = u_volt - tol;
+	new_opp->supplies[0].u_volt_max = u_volt + tol;
+	new_opp->available = true;
+	new_opp->dynamic = dynamic;
+
+	ret = _opp_add(dev, new_opp, opp_table);
+	if (ret) {
+		/* Don't return error for duplicate OPPs */
+		if (ret == -EBUSY)
+			ret = 0;
+		goto free_opp;
+	}
+
+	/*
+	 * Notify the changes in the availability of the operable
+	 * frequency/voltage list.
+	 */
+	blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_ADD, new_opp);
+	return 0;
+
+free_opp:
+	_opp_free(new_opp);
+
+	return ret;
+}
+
+/**
+ * dev_pm_opp_set_supported_hw() - Set supported platforms
+ * @dev: Device for which supported-hw has to be set.
+ * @versions: Array of hierarchy of versions to match.
+ * @count: Number of elements in the array.
+ *
+ * This is required only for the V2 bindings, and it enables a platform to
+ * specify the hierarchy of versions it supports. OPP layer will then enable
+ * OPPs, which are available for those versions, based on its 'opp-supported-hw'
+ * property.
+ */
+struct opp_table *dev_pm_opp_set_supported_hw(struct device *dev,
+			const u32 *versions, unsigned int count)
+{
+	struct opp_table *opp_table;
+	int ret;
+
+	opp_table = dev_pm_opp_get_opp_table(dev);
+	if (!opp_table)
+		return ERR_PTR(-ENOMEM);
+
+	/* Make sure there are no concurrent readers while updating opp_table */
+	WARN_ON(!list_empty(&opp_table->opp_list));
+
+	/* Do we already have a version hierarchy associated with opp_table? */
+	if (opp_table->supported_hw) {
+		dev_err(dev, "%s: Already have supported hardware list\n",
+			__func__);
+		ret = -EBUSY;
+		goto err;
+	}
+
+	opp_table->supported_hw = kmemdup(versions, count * sizeof(*versions),
+					GFP_KERNEL);
+	if (!opp_table->supported_hw) {
+		ret = -ENOMEM;
+		goto err;
+	}
+
+	opp_table->supported_hw_count = count;
+
+	return opp_table;
+
+err:
+	dev_pm_opp_put_opp_table(opp_table);
+
+	return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_set_supported_hw);
+
+/**
+ * dev_pm_opp_put_supported_hw() - Releases resources blocked for supported hw
+ * @opp_table: OPP table returned by dev_pm_opp_set_supported_hw().
+ *
+ * This is required only for the V2 bindings, and is called for a matching
+ * dev_pm_opp_set_supported_hw(). Until this is called, the opp_table structure
+ * will not be freed.
+ */
+void dev_pm_opp_put_supported_hw(struct opp_table *opp_table)
+{
+	/* Make sure there are no concurrent readers while updating opp_table */
+	WARN_ON(!list_empty(&opp_table->opp_list));
+
+	if (!opp_table->supported_hw) {
+		pr_err("%s: Doesn't have supported hardware list\n",
+		       __func__);
+		return;
+	}
+
+	kfree(opp_table->supported_hw);
+	opp_table->supported_hw = NULL;
+	opp_table->supported_hw_count = 0;
+
+	dev_pm_opp_put_opp_table(opp_table);
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_put_supported_hw);
+
+/**
+ * dev_pm_opp_set_prop_name() - Set prop-extn name
+ * @dev: Device for which the prop-name has to be set.
+ * @name: name to postfix to properties.
+ *
+ * This is required only for the V2 bindings, and it enables a platform to
+ * specify the extn to be used for certain property names. The properties to
+ * which the extension will apply are opp-microvolt and opp-microamp. OPP core
+ * should postfix the property name with -<name> while looking for them.
+ */
+struct opp_table *dev_pm_opp_set_prop_name(struct device *dev, const char *name)
+{
+	struct opp_table *opp_table;
+	int ret;
+
+	opp_table = dev_pm_opp_get_opp_table(dev);
+	if (!opp_table)
+		return ERR_PTR(-ENOMEM);
+
+	/* Make sure there are no concurrent readers while updating opp_table */
+	WARN_ON(!list_empty(&opp_table->opp_list));
+
+	/* Do we already have a prop-name associated with opp_table? */
+	if (opp_table->prop_name) {
+		dev_err(dev, "%s: Already have prop-name %s\n", __func__,
+			opp_table->prop_name);
+		ret = -EBUSY;
+		goto err;
+	}
+
+	opp_table->prop_name = kstrdup(name, GFP_KERNEL);
+	if (!opp_table->prop_name) {
+		ret = -ENOMEM;
+		goto err;
+	}
+
+	return opp_table;
+
+err:
+	dev_pm_opp_put_opp_table(opp_table);
+
+	return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_set_prop_name);
+
+/**
+ * dev_pm_opp_put_prop_name() - Releases resources blocked for prop-name
+ * @opp_table: OPP table returned by dev_pm_opp_set_prop_name().
+ *
+ * This is required only for the V2 bindings, and is called for a matching
+ * dev_pm_opp_set_prop_name(). Until this is called, the opp_table structure
+ * will not be freed.
+ */
+void dev_pm_opp_put_prop_name(struct opp_table *opp_table)
+{
+	/* Make sure there are no concurrent readers while updating opp_table */
+	WARN_ON(!list_empty(&opp_table->opp_list));
+
+	if (!opp_table->prop_name) {
+		pr_err("%s: Doesn't have a prop-name\n", __func__);
+		return;
+	}
+
+	kfree(opp_table->prop_name);
+	opp_table->prop_name = NULL;
+
+	dev_pm_opp_put_opp_table(opp_table);
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_put_prop_name);
+
+static int _allocate_set_opp_data(struct opp_table *opp_table)
+{
+	struct dev_pm_set_opp_data *data;
+	int len, count = opp_table->regulator_count;
+
+	if (WARN_ON(!count))
+		return -EINVAL;
+
+	/* space for set_opp_data */
+	len = sizeof(*data);
+
+	/* space for old_opp.supplies and new_opp.supplies */
+	len += 2 * sizeof(struct dev_pm_opp_supply) * count;
+
+	data = kzalloc(len, GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->old_opp.supplies = (void *)(data + 1);
+	data->new_opp.supplies = data->old_opp.supplies + count;
+
+	opp_table->set_opp_data = data;
+
+	return 0;
+}
+
+static void _free_set_opp_data(struct opp_table *opp_table)
+{
+	kfree(opp_table->set_opp_data);
+	opp_table->set_opp_data = NULL;
+}
+
+/**
+ * dev_pm_opp_set_regulators() - Set regulator names for the device
+ * @dev: Device for which regulator name is being set.
+ * @names: Array of pointers to the names of the regulator.
+ * @count: Number of regulators.
+ *
+ * In order to support OPP switching, OPP layer needs to know the name of the
+ * device's regulators, as the core would be required to switch voltages as
+ * well.
+ *
+ * This must be called before any OPPs are initialized for the device.
+ */
+struct opp_table *dev_pm_opp_set_regulators(struct device *dev,
+					    const char * const names[],
+					    unsigned int count)
+{
+	struct opp_table *opp_table;
+	struct regulator *reg;
+	int ret, i;
+
+	opp_table = dev_pm_opp_get_opp_table(dev);
+	if (!opp_table)
+		return ERR_PTR(-ENOMEM);
+
+	/* This should be called before OPPs are initialized */
+	if (WARN_ON(!list_empty(&opp_table->opp_list))) {
+		ret = -EBUSY;
+		goto err;
+	}
+
+	/* Already have regulators set */
+	if (opp_table->regulators) {
+		ret = -EBUSY;
+		goto err;
+	}
+
+	opp_table->regulators = kmalloc_array(count,
+					      sizeof(*opp_table->regulators),
+					      GFP_KERNEL);
+	if (!opp_table->regulators) {
+		ret = -ENOMEM;
+		goto err;
+	}
+
+	for (i = 0; i < count; i++) {
+		reg = regulator_get_optional(dev, names[i]);
+		if (IS_ERR(reg)) {
+			ret = PTR_ERR(reg);
+			if (ret != -EPROBE_DEFER)
+				dev_err(dev, "%s: no regulator (%s) found: %d\n",
+					__func__, names[i], ret);
+			goto free_regulators;
+		}
+
+		opp_table->regulators[i] = reg;
+	}
+
+	opp_table->regulator_count = count;
+
+	/* Allocate block only once to pass to set_opp() routines */
+	ret = _allocate_set_opp_data(opp_table);
+	if (ret)
+		goto free_regulators;
+
+	return opp_table;
+
+free_regulators:
+	while (i != 0)
+		regulator_put(opp_table->regulators[--i]);
+
+	kfree(opp_table->regulators);
+	opp_table->regulators = NULL;
+	opp_table->regulator_count = 0;
+err:
+	dev_pm_opp_put_opp_table(opp_table);
+
+	return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_set_regulators);
+
+/**
+ * dev_pm_opp_put_regulators() - Releases resources blocked for regulator
+ * @opp_table: OPP table returned from dev_pm_opp_set_regulators().
+ */
+void dev_pm_opp_put_regulators(struct opp_table *opp_table)
+{
+	int i;
+
+	if (!opp_table->regulators) {
+		pr_err("%s: Doesn't have regulators set\n", __func__);
+		return;
+	}
+
+	/* Make sure there are no concurrent readers while updating opp_table */
+	WARN_ON(!list_empty(&opp_table->opp_list));
+
+	for (i = opp_table->regulator_count - 1; i >= 0; i--)
+		regulator_put(opp_table->regulators[i]);
+
+	_free_set_opp_data(opp_table);
+
+	kfree(opp_table->regulators);
+	opp_table->regulators = NULL;
+	opp_table->regulator_count = 0;
+
+	dev_pm_opp_put_opp_table(opp_table);
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_put_regulators);
+
+/**
+ * dev_pm_opp_set_clkname() - Set clk name for the device
+ * @dev: Device for which clk name is being set.
+ * @name: Clk name.
+ *
+ * In order to support OPP switching, OPP layer needs to get pointer to the
+ * clock for the device. Simple cases work fine without using this routine (i.e.
+ * by passing connection-id as NULL), but for a device with multiple clocks
+ * available, the OPP core needs to know the exact name of the clk to use.
+ *
+ * This must be called before any OPPs are initialized for the device.
+ */
+struct opp_table *dev_pm_opp_set_clkname(struct device *dev, const char *name)
+{
+	struct opp_table *opp_table;
+	int ret;
+
+	opp_table = dev_pm_opp_get_opp_table(dev);
+	if (!opp_table)
+		return ERR_PTR(-ENOMEM);
+
+	/* This should be called before OPPs are initialized */
+	if (WARN_ON(!list_empty(&opp_table->opp_list))) {
+		ret = -EBUSY;
+		goto err;
+	}
+
+	/* Already have default clk set, free it */
+	if (!IS_ERR(opp_table->clk))
+		clk_put(opp_table->clk);
+
+	/* Find clk for the device */
+	opp_table->clk = clk_get(dev, name);
+	if (IS_ERR(opp_table->clk)) {
+		ret = PTR_ERR(opp_table->clk);
+		if (ret != -EPROBE_DEFER) {
+			dev_err(dev, "%s: Couldn't find clock: %d\n", __func__,
+				ret);
+		}
+		goto err;
+	}
+
+	return opp_table;
+
+err:
+	dev_pm_opp_put_opp_table(opp_table);
+
+	return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_set_clkname);
+
+/**
+ * dev_pm_opp_put_clkname() - Releases resources blocked for clk.
+ * @opp_table: OPP table returned from dev_pm_opp_set_clkname().
+ */
+void dev_pm_opp_put_clkname(struct opp_table *opp_table)
+{
+	/* Make sure there are no concurrent readers while updating opp_table */
+	WARN_ON(!list_empty(&opp_table->opp_list));
+
+	clk_put(opp_table->clk);
+	opp_table->clk = ERR_PTR(-EINVAL);
+
+	dev_pm_opp_put_opp_table(opp_table);
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_put_clkname);
+
+/**
+ * dev_pm_opp_register_set_opp_helper() - Register custom set OPP helper
+ * @dev: Device for which the helper is getting registered.
+ * @set_opp: Custom set OPP helper.
+ *
+ * This is useful to support complex platforms (like platforms with multiple
+ * regulators per device), instead of the generic OPP set rate helper.
+ *
+ * This must be called before any OPPs are initialized for the device.
+ */
+struct opp_table *dev_pm_opp_register_set_opp_helper(struct device *dev,
+			int (*set_opp)(struct dev_pm_set_opp_data *data))
+{
+	struct opp_table *opp_table;
+	int ret;
+
+	if (!set_opp)
+		return ERR_PTR(-EINVAL);
+
+	opp_table = dev_pm_opp_get_opp_table(dev);
+	if (!opp_table)
+		return ERR_PTR(-ENOMEM);
+
+	/* This should be called before OPPs are initialized */
+	if (WARN_ON(!list_empty(&opp_table->opp_list))) {
+		ret = -EBUSY;
+		goto err;
+	}
+
+	/* Already have custom set_opp helper */
+	if (WARN_ON(opp_table->set_opp)) {
+		ret = -EBUSY;
+		goto err;
+	}
+
+	opp_table->set_opp = set_opp;
+
+	return opp_table;
+
+err:
+	dev_pm_opp_put_opp_table(opp_table);
+
+	return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_register_set_opp_helper);
+
+/**
+ * dev_pm_opp_unregister_set_opp_helper() - Releases resources blocked for
+ *					   set_opp helper
+ * @opp_table: OPP table returned from dev_pm_opp_register_set_opp_helper().
+ *
+ * Release resources blocked for platform specific set_opp helper.
+ */
+void dev_pm_opp_unregister_set_opp_helper(struct opp_table *opp_table)
+{
+	if (!opp_table->set_opp) {
+		pr_err("%s: Doesn't have custom set_opp helper set\n",
+		       __func__);
+		return;
+	}
+
+	/* Make sure there are no concurrent readers while updating opp_table */
+	WARN_ON(!list_empty(&opp_table->opp_list));
+
+	opp_table->set_opp = NULL;
+
+	dev_pm_opp_put_opp_table(opp_table);
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_unregister_set_opp_helper);
+
+/**
+ * dev_pm_opp_register_get_pstate_helper() - Register get_pstate() helper.
+ * @dev: Device for which the helper is getting registered.
+ * @get_pstate: Helper.
+ *
+ * TODO: Remove this callback after the same information is available via Device
+ * Tree.
+ *
+ * This allows a platform to initialize the performance states of individual
+ * OPPs for its devices, until we get similar information directly from DT.
+ *
+ * This must be called before the OPPs are initialized for the device.
+ */
+struct opp_table *dev_pm_opp_register_get_pstate_helper(struct device *dev,
+		int (*get_pstate)(struct device *dev, unsigned long rate))
+{
+	struct opp_table *opp_table;
+	int ret;
+
+	if (!get_pstate)
+		return ERR_PTR(-EINVAL);
+
+	opp_table = dev_pm_opp_get_opp_table(dev);
+	if (!opp_table)
+		return ERR_PTR(-ENOMEM);
+
+	/* This should be called before OPPs are initialized */
+	if (WARN_ON(!list_empty(&opp_table->opp_list))) {
+		ret = -EBUSY;
+		goto err;
+	}
+
+	/* Already have genpd_performance_state set */
+	if (WARN_ON(opp_table->genpd_performance_state)) {
+		ret = -EBUSY;
+		goto err;
+	}
+
+	opp_table->genpd_performance_state = true;
+	opp_table->get_pstate = get_pstate;
+
+	return opp_table;
+
+err:
+	dev_pm_opp_put_opp_table(opp_table);
+
+	return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_register_get_pstate_helper);
+
+/**
+ * dev_pm_opp_unregister_get_pstate_helper() - Releases resources blocked for
+ *					   get_pstate() helper
+ * @opp_table: OPP table returned from dev_pm_opp_register_get_pstate_helper().
+ *
+ * Release resources blocked for platform specific get_pstate() helper.
+ */
+void dev_pm_opp_unregister_get_pstate_helper(struct opp_table *opp_table)
+{
+	if (!opp_table->genpd_performance_state) {
+		pr_err("%s: Doesn't have performance states set\n",
+		       __func__);
+		return;
+	}
+
+	/* Make sure there are no concurrent readers while updating opp_table */
+	WARN_ON(!list_empty(&opp_table->opp_list));
+
+	opp_table->genpd_performance_state = false;
+	opp_table->get_pstate = NULL;
+
+	dev_pm_opp_put_opp_table(opp_table);
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_unregister_get_pstate_helper);
+
+/**
+ * dev_pm_opp_add()  - Add an OPP table from a table definitions
+ * @dev:	device for which we do this operation
+ * @freq:	Frequency in Hz for this OPP
+ * @u_volt:	Voltage in uVolts for this OPP
+ *
+ * This function adds an opp definition to the opp table and returns status.
+ * The opp is made available by default and it can be controlled using
+ * dev_pm_opp_enable/disable functions.
+ *
+ * Return:
+ * 0		On success OR
+ *		Duplicate OPPs (both freq and volt are same) and opp->available
+ * -EEXIST	Freq are same and volt are different OR
+ *		Duplicate OPPs (both freq and volt are same) and !opp->available
+ * -ENOMEM	Memory allocation failure
+ */
+int dev_pm_opp_add(struct device *dev, unsigned long freq, unsigned long u_volt)
+{
+	struct opp_table *opp_table;
+	int ret;
+
+	opp_table = dev_pm_opp_get_opp_table(dev);
+	if (!opp_table)
+		return -ENOMEM;
+
+	ret = _opp_add_v1(opp_table, dev, freq, u_volt, true);
+
+	dev_pm_opp_put_opp_table(opp_table);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_add);
+
+/**
+ * _opp_set_availability() - helper to set the availability of an opp
+ * @dev:		device for which we do this operation
+ * @freq:		OPP frequency to modify availability
+ * @availability_req:	availability status requested for this opp
+ *
+ * Set the availability of an OPP, opp_{enable,disable} share a common logic
+ * which is isolated here.
+ *
+ * Return: -EINVAL for bad pointers, -ENOMEM if no memory available for the
+ * copy operation, returns 0 if no modification was done OR modification was
+ * successful.
+ */
+static int _opp_set_availability(struct device *dev, unsigned long freq,
+				 bool availability_req)
+{
+	struct opp_table *opp_table;
+	struct dev_pm_opp *tmp_opp, *opp = ERR_PTR(-ENODEV);
+	int r = 0;
+
+	/* Find the opp_table */
+	opp_table = _find_opp_table(dev);
+	if (IS_ERR(opp_table)) {
+		r = PTR_ERR(opp_table);
+		dev_warn(dev, "%s: Device OPP not found (%d)\n", __func__, r);
+		return r;
+	}
+
+	mutex_lock(&opp_table->lock);
+
+	/* Do we have the frequency? */
+	list_for_each_entry(tmp_opp, &opp_table->opp_list, node) {
+		if (tmp_opp->rate == freq) {
+			opp = tmp_opp;
+			break;
+		}
+	}
+
+	if (IS_ERR(opp)) {
+		r = PTR_ERR(opp);
+		goto unlock;
+	}
+
+	/* Is update really needed? */
+	if (opp->available == availability_req)
+		goto unlock;
+
+	opp->available = availability_req;
+
+	dev_pm_opp_get(opp);
+	mutex_unlock(&opp_table->lock);
+
+	/* Notify the change of the OPP availability */
+	if (availability_req)
+		blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_ENABLE,
+					     opp);
+	else
+		blocking_notifier_call_chain(&opp_table->head,
+					     OPP_EVENT_DISABLE, opp);
+
+	dev_pm_opp_put(opp);
+	goto put_table;
+
+unlock:
+	mutex_unlock(&opp_table->lock);
+put_table:
+	dev_pm_opp_put_opp_table(opp_table);
+	return r;
+}
+
+/**
+ * dev_pm_opp_enable() - Enable a specific OPP
+ * @dev:	device for which we do this operation
+ * @freq:	OPP frequency to enable
+ *
+ * Enables a provided opp. If the operation is valid, this returns 0, else the
+ * corresponding error value. It is meant to be used for users an OPP available
+ * after being temporarily made unavailable with dev_pm_opp_disable.
+ *
+ * Return: -EINVAL for bad pointers, -ENOMEM if no memory available for the
+ * copy operation, returns 0 if no modification was done OR modification was
+ * successful.
+ */
+int dev_pm_opp_enable(struct device *dev, unsigned long freq)
+{
+	return _opp_set_availability(dev, freq, true);
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_enable);
+
+/**
+ * dev_pm_opp_disable() - Disable a specific OPP
+ * @dev:	device for which we do this operation
+ * @freq:	OPP frequency to disable
+ *
+ * Disables a provided opp. If the operation is valid, this returns
+ * 0, else the corresponding error value. It is meant to be a temporary
+ * control by users to make this OPP not available until the circumstances are
+ * right to make it available again (with a call to dev_pm_opp_enable).
+ *
+ * Return: -EINVAL for bad pointers, -ENOMEM if no memory available for the
+ * copy operation, returns 0 if no modification was done OR modification was
+ * successful.
+ */
+int dev_pm_opp_disable(struct device *dev, unsigned long freq)
+{
+	return _opp_set_availability(dev, freq, false);
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_disable);
+
+/**
+ * dev_pm_opp_register_notifier() - Register OPP notifier for the device
+ * @dev:	Device for which notifier needs to be registered
+ * @nb:		Notifier block to be registered
+ *
+ * Return: 0 on success or a negative error value.
+ */
+int dev_pm_opp_register_notifier(struct device *dev, struct notifier_block *nb)
+{
+	struct opp_table *opp_table;
+	int ret;
+
+	opp_table = _find_opp_table(dev);
+	if (IS_ERR(opp_table))
+		return PTR_ERR(opp_table);
+
+	ret = blocking_notifier_chain_register(&opp_table->head, nb);
+
+	dev_pm_opp_put_opp_table(opp_table);
+
+	return ret;
+}
+EXPORT_SYMBOL(dev_pm_opp_register_notifier);
+
+/**
+ * dev_pm_opp_unregister_notifier() - Unregister OPP notifier for the device
+ * @dev:	Device for which notifier needs to be unregistered
+ * @nb:		Notifier block to be unregistered
+ *
+ * Return: 0 on success or a negative error value.
+ */
+int dev_pm_opp_unregister_notifier(struct device *dev,
+				   struct notifier_block *nb)
+{
+	struct opp_table *opp_table;
+	int ret;
+
+	opp_table = _find_opp_table(dev);
+	if (IS_ERR(opp_table))
+		return PTR_ERR(opp_table);
+
+	ret = blocking_notifier_chain_unregister(&opp_table->head, nb);
+
+	dev_pm_opp_put_opp_table(opp_table);
+
+	return ret;
+}
+EXPORT_SYMBOL(dev_pm_opp_unregister_notifier);
+
+/*
+ * Free OPPs either created using static entries present in DT or even the
+ * dynamically added entries based on remove_all param.
+ */
+void _dev_pm_opp_remove_table(struct opp_table *opp_table, struct device *dev,
+			      bool remove_all)
+{
+	struct dev_pm_opp *opp, *tmp;
+
+	/* Find if opp_table manages a single device */
+	if (list_is_singular(&opp_table->dev_list)) {
+		/* Free static OPPs */
+		list_for_each_entry_safe(opp, tmp, &opp_table->opp_list, node) {
+			if (remove_all || !opp->dynamic)
+				dev_pm_opp_put(opp);
+		}
+
+		/*
+		 * The OPP table is getting removed, drop the performance state
+		 * constraints.
+		 */
+		if (opp_table->genpd_performance_state)
+			dev_pm_genpd_set_performance_state(dev, 0);
+	} else {
+		_remove_opp_dev(_find_opp_dev(dev, opp_table), opp_table);
+	}
+}
+
+void _dev_pm_opp_find_and_remove_table(struct device *dev, bool remove_all)
+{
+	struct opp_table *opp_table;
+
+	/* Check for existing table for 'dev' */
+	opp_table = _find_opp_table(dev);
+	if (IS_ERR(opp_table)) {
+		int error = PTR_ERR(opp_table);
+
+		if (error != -ENODEV)
+			WARN(1, "%s: opp_table: %d\n",
+			     IS_ERR_OR_NULL(dev) ?
+					"Invalid device" : dev_name(dev),
+			     error);
+		return;
+	}
+
+	_dev_pm_opp_remove_table(opp_table, dev, remove_all);
+
+	dev_pm_opp_put_opp_table(opp_table);
+}
+
+/**
+ * dev_pm_opp_remove_table() - Free all OPPs associated with the device
+ * @dev:	device pointer used to lookup OPP table.
+ *
+ * Free both OPPs created using static entries present in DT and the
+ * dynamically added entries.
+ */
+void dev_pm_opp_remove_table(struct device *dev)
+{
+	_dev_pm_opp_find_and_remove_table(dev, true);
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_remove_table);