drivers/opp/ti-opp-supply.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /*
  * Copyright (C) 2016-2017 Texas Instruments Incorporated - http://www.ti.com/
  *	Nishanth Menon <nm@ti.com>
  *	Dave Gerlach <d-gerlach@ti.com>
  *
  * TI OPP supply driver that provides override into the regulator control
  * for generic opp core to handle devices with ABB regulator and/or
  * SmartReflex Class0.
  */
 #include <linux/clk.h>
 #include <linux/cpufreq.h>
 #include <linux/device.h>
 #include <linux/io.h>
 #include <linux/module.h>
 #include <linux/notifier.h>
 #include <linux/of_device.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/pm_opp.h>
 #include <linux/regulator/consumer.h>
 #include <linux/slab.h>

 /**
  * struct ti_opp_supply_optimum_voltage_table - optimized voltage table
  * @reference_uv:	reference voltage (usually Nominal voltage)
  * @optimized_uv:	Optimized voltage from efuse
  */
 struct ti_opp_supply_optimum_voltage_table {
 	unsigned int reference_uv;
 	unsigned int optimized_uv;
 };

 /**
  * struct ti_opp_supply_data - OMAP specific opp supply data
  * @vdd_table:	Optimized voltage mapping table
  * @num_vdd_table: number of entries in vdd_table
  * @vdd_absolute_max_voltage_uv: absolute maximum voltage in UV for the supply
  */
 struct ti_opp_supply_data {
 	struct ti_opp_supply_optimum_voltage_table *vdd_table;
 	u32 num_vdd_table;
 	u32 vdd_absolute_max_voltage_uv;
 };

 static struct ti_opp_supply_data opp_data;

 /**
  * struct ti_opp_supply_of_data - device tree match data
  * @flags:	specific type of opp supply
  * @efuse_voltage_mask: mask required for efuse register representing voltage
  * @efuse_voltage_uv: Are the efuse entries in micro-volts? if not, assume
  *		milli-volts.
  */
 struct ti_opp_supply_of_data {
 #define OPPDM_EFUSE_CLASS0_OPTIMIZED_VOLTAGE	BIT(1)
 #define OPPDM_HAS_NO_ABB			BIT(2)
 	const u8 flags;
 	const u32 efuse_voltage_mask;
 	const bool efuse_voltage_uv;
 };

 /**
  * _store_optimized_voltages() - store optimized voltages
  * @dev:	ti opp supply device for which we need to store info
  * @data:	data specific to the device
  *
  * Picks up efuse based optimized voltages for VDD unique per device and
  * stores it in internal data structure for use during transition requests.
  *
  * Return: If successful, 0, else appropriate error value.
  */
 static int _store_optimized_voltages(struct device *dev,
 				     struct ti_opp_supply_data *data)
 {
 	void __iomem *base;
 	struct property *prop;
 	struct resource *res;
 	const __be32 *val;
 	int proplen, i;
 	int ret = 0;
 	struct ti_opp_supply_optimum_voltage_table *table;
 	const struct ti_opp_supply_of_data *of_data = dev_get_drvdata(dev);

 	/* pick up Efuse based voltages */
 	res = platform_get_resource(to_platform_device(dev), IORESOURCE_MEM, 0);
 	if (!res) {
 		dev_err(dev, "Unable to get IO resource\n");
 		ret = -ENODEV;
 		goto out_map;
 	}

 	base = ioremap(res->start, resource_size(res));
 	if (!base) {
 		dev_err(dev, "Unable to map Efuse registers\n");
 		ret = -ENOMEM;
 		goto out_map;
 	}

 	/* Fetch efuse-settings. */
 	prop = of_find_property(dev->of_node, "ti,efuse-settings", NULL);
 	if (!prop) {
 		dev_err(dev, "No 'ti,efuse-settings' property found\n");
 		ret = -EINVAL;
 		goto out;
 	}

 	proplen = prop->length / sizeof(int);
 	data->num_vdd_table = proplen / 2;
 	/* Verify for corrupted OPP entries in dt */
 	if (data->num_vdd_table * 2 * sizeof(int) != prop->length) {
 		dev_err(dev, "Invalid 'ti,efuse-settings'\n");
 		ret = -EINVAL;
 		goto out;
 	}

 	ret = of_property_read_u32(dev->of_node, "ti,absolute-max-voltage-uv",
 				   &data->vdd_absolute_max_voltage_uv);
 	if (ret) {
 		dev_err(dev, "ti,absolute-max-voltage-uv is missing\n");
 		ret = -EINVAL;
 		goto out;
 	}

 	table = kcalloc(data->num_vdd_table, sizeof(*data->vdd_table),
 			GFP_KERNEL);
 	if (!table) {
 		ret = -ENOMEM;
 		goto out;
 	}
 	data->vdd_table = table;

 	val = prop->value;
 	for (i = 0; i < data->num_vdd_table; i++, table++) {
 		u32 efuse_offset;
 		u32 tmp;

 		table->reference_uv = be32_to_cpup(val++);
 		efuse_offset = be32_to_cpup(val++);

 		tmp = readl(base + efuse_offset);
 		tmp &= of_data->efuse_voltage_mask;
 		tmp >>= __ffs(of_data->efuse_voltage_mask);

 		table->optimized_uv = of_data->efuse_voltage_uv ? tmp :
 					tmp * 1000;

 		dev_dbg(dev, "[%d] efuse=0x%08x volt_table=%d vset=%d\n",
 			i, efuse_offset, table->reference_uv,
 			table->optimized_uv);

 		/*
 		 * Some older samples might not have optimized efuse
 		 * Use reference voltage for those - just add debug message
 		 * for them.
 		 */
 		if (!table->optimized_uv) {
 			dev_dbg(dev, "[%d] efuse=0x%08x volt_table=%d:vset0\n",
 				i, efuse_offset, table->reference_uv);
 			table->optimized_uv = table->reference_uv;
 		}
 	}
 out:
 	iounmap(base);
 out_map:
 	return ret;
 }

 /**
  * _free_optimized_voltages() - free resources for optvoltages
  * @dev:	device for which we need to free info
  * @data:	data specific to the device
  */
 static void _free_optimized_voltages(struct device *dev,
 				     struct ti_opp_supply_data *data)
 {
 	kfree(data->vdd_table);
 	data->vdd_table = NULL;
 	data->num_vdd_table = 0;
 }

 /**
  * _get_optimal_vdd_voltage() - Finds optimal voltage for the supply
  * @dev:	device for which we need to find info
  * @data:	data specific to the device
  * @reference_uv:	reference voltage (OPP voltage) for which we need value
  *
  * Return: if a match is found, return optimized voltage, else return
  * reference_uv, also return reference_uv if no optimization is needed.
  */
 static int _get_optimal_vdd_voltage(struct device *dev,
 				    struct ti_opp_supply_data *data,
 				    int reference_uv)
 {
 	int i;
 	struct ti_opp_supply_optimum_voltage_table *table;

 	if (!data->num_vdd_table)
 		return reference_uv;

 	table = data->vdd_table;
 	if (!table)
 		return -EINVAL;

 	/* Find a exact match - this list is usually very small */
 	for (i = 0; i < data->num_vdd_table; i++, table++)
 		if (table->reference_uv == reference_uv)
 			return table->optimized_uv;

 	/* IF things are screwed up, we'd make a mess on console.. ratelimit */
 	dev_err_ratelimited(dev, "%s: Failed optimized voltage match for %d\n",
 			    __func__, reference_uv);
 	return reference_uv;
 }

 static int _opp_set_voltage(struct device *dev,
 			    struct dev_pm_opp_supply *supply,
 			    int new_target_uv, struct regulator *reg,
 			    char *reg_name)
 {
 	int ret;
 	unsigned long vdd_uv, uv_max;

 	if (new_target_uv)
 		vdd_uv = new_target_uv;
 	else
 		vdd_uv = supply->u_volt;

 	/*
 	 * If we do have an absolute max voltage specified, then we should
 	 * use that voltage instead to allow for cases where the voltage rails
 	 * are ganged (example if we set the max for an opp as 1.12v, and
 	 * the absolute max is 1.5v, for another rail to get 1.25v, it cannot
 	 * be achieved if the regulator is constrainted to max of 1.12v, even
 	 * if it can function at 1.25v
 	 */
 	if (opp_data.vdd_absolute_max_voltage_uv)
 		uv_max = opp_data.vdd_absolute_max_voltage_uv;
 	else
 		uv_max = supply->u_volt_max;

 	if (vdd_uv > uv_max ||
 	    vdd_uv < supply->u_volt_min ||
 	    supply->u_volt_min > uv_max) {
 		dev_warn(dev,
 			 "Invalid range voltages [Min:%lu target:%lu Max:%lu]\n",
 			 supply->u_volt_min, vdd_uv, uv_max);
 		return -EINVAL;
 	}

 	dev_dbg(dev, "%s scaling to %luuV[min %luuV max %luuV]\n", reg_name,
 		vdd_uv, supply->u_volt_min,
 		uv_max);

 	ret = regulator_set_voltage_triplet(reg,
 					    supply->u_volt_min,
 					    vdd_uv,
 					    uv_max);
 	if (ret) {
 		dev_err(dev, "%s failed for %luuV[min %luuV max %luuV]\n",
 			reg_name, vdd_uv, supply->u_volt_min,
 			uv_max);
 		return ret;
 	}

 	return 0;
 }

 /**
  * ti_opp_supply_set_opp() - do the opp supply transition
  * @data:	information on regulators and new and old opps provided by
  *		opp core to use in transition
  *
  * Return: If successful, 0, else appropriate error value.
  */
 static int ti_opp_supply_set_opp(struct dev_pm_set_opp_data *data)
 {
 	struct dev_pm_opp_supply *old_supply_vdd = &data->old_opp.supplies[0];
 	struct dev_pm_opp_supply *old_supply_vbb = &data->old_opp.supplies[1];
 	struct dev_pm_opp_supply *new_supply_vdd = &data->new_opp.supplies[0];
 	struct dev_pm_opp_supply *new_supply_vbb = &data->new_opp.supplies[1];
 	struct device *dev = data->dev;
 	unsigned long old_freq = data->old_opp.rate, freq = data->new_opp.rate;
 	struct clk *clk = data->clk;
 	struct regulator *vdd_reg = data->regulators[0];
 	struct regulator *vbb_reg = data->regulators[1];
 	int vdd_uv;
 	int ret;

 	vdd_uv = _get_optimal_vdd_voltage(dev, &opp_data,
 					  new_supply_vdd->u_volt);

 	if (new_supply_vdd->u_volt_min < vdd_uv)
 		new_supply_vdd->u_volt_min = vdd_uv;

 	/* Scaling up? Scale voltage before frequency */
 	if (freq > old_freq) {
 		ret = _opp_set_voltage(dev, new_supply_vdd, vdd_uv, vdd_reg,
 				       "vdd");
 		if (ret)
 			goto restore_voltage;

 		ret = _opp_set_voltage(dev, new_supply_vbb, 0, vbb_reg, "vbb");
 		if (ret)
 			goto restore_voltage;
 	}

 	/* Change frequency */
 	dev_dbg(dev, "%s: switching OPP: %lu Hz --> %lu Hz\n",
 		__func__, old_freq, freq);

 	ret = clk_set_rate(clk, freq);
 	if (ret) {
 		dev_err(dev, "%s: failed to set clock rate: %d\n", __func__,
 			ret);
 		goto restore_voltage;
 	}

 	/* Scaling down? Scale voltage after frequency */
 	if (freq < old_freq) {
 		ret = _opp_set_voltage(dev, new_supply_vbb, 0, vbb_reg, "vbb");
 		if (ret)
 			goto restore_freq;

 		ret = _opp_set_voltage(dev, new_supply_vdd, vdd_uv, vdd_reg,
 				       "vdd");
 		if (ret)
 			goto restore_freq;
 	}

 	return 0;

 restore_freq:
 	ret = clk_set_rate(clk, old_freq);
 	if (ret)
 		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_vdd->u_volt) {
 		ret = _opp_set_voltage(dev, old_supply_vbb, 0, vbb_reg, "vbb");
 		if (ret)
 			return ret;

 		ret = _opp_set_voltage(dev, old_supply_vdd, 0, vdd_reg,
 				       "vdd");
 		if (ret)
 			return ret;
 	}

 	return ret;
 }

 static const struct ti_opp_supply_of_data omap_generic_of_data = {
 };

 static const struct ti_opp_supply_of_data omap_omap5_of_data = {
 	.flags = OPPDM_EFUSE_CLASS0_OPTIMIZED_VOLTAGE,
 	.efuse_voltage_mask = 0xFFF,
 	.efuse_voltage_uv = false,
 };

 static const struct ti_opp_supply_of_data omap_omap5core_of_data = {
 	.flags = OPPDM_EFUSE_CLASS0_OPTIMIZED_VOLTAGE | OPPDM_HAS_NO_ABB,
 	.efuse_voltage_mask = 0xFFF,
 	.efuse_voltage_uv = false,
 };

 static const struct of_device_id ti_opp_supply_of_match[] = {
 	{.compatible = "ti,omap-opp-supply", .data = &omap_generic_of_data},
 	{.compatible = "ti,omap5-opp-supply", .data = &omap_omap5_of_data},
 	{.compatible = "ti,omap5-core-opp-supply",
 	 .data = &omap_omap5core_of_data},
 	{},
 };
 MODULE_DEVICE_TABLE(of, ti_opp_supply_of_match);

 static int ti_opp_supply_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct device *cpu_dev = get_cpu_device(0);
 	const struct of_device_id *match;
 	const struct ti_opp_supply_of_data *of_data;
 	int ret = 0;

 	match = of_match_device(ti_opp_supply_of_match, dev);
 	if (!match) {
 		/* We do not expect this to happen */
 		dev_err(dev, "%s: Unable to match device\n", __func__);
 		return -ENODEV;
 	}
 	if (!match->data) {
 		/* Again, unlikely.. but mistakes do happen */
 		dev_err(dev, "%s: Bad data in match\n", __func__);
 		return -EINVAL;
 	}
 	of_data = match->data;

 	dev_set_drvdata(dev, (void *)of_data);

 	/* If we need optimized voltage */
 	if (of_data->flags & OPPDM_EFUSE_CLASS0_OPTIMIZED_VOLTAGE) {
 		ret = _store_optimized_voltages(dev, &opp_data);
 		if (ret)
 			return ret;
 	}

 	ret = PTR_ERR_OR_ZERO(dev_pm_opp_register_set_opp_helper(cpu_dev,
 								 ti_opp_supply_set_opp));
 	if (ret)
 		_free_optimized_voltages(dev, &opp_data);

 	return ret;
 }

 static struct platform_driver ti_opp_supply_driver = {
 	.probe = ti_opp_supply_probe,
 	.driver = {
 		   .name = "ti_opp_supply",
 		   .of_match_table = of_match_ptr(ti_opp_supply_of_match),
 		   },
 };
 module_platform_driver(ti_opp_supply_driver);

 MODULE_DESCRIPTION("Texas Instruments OMAP OPP Supply driver");
 MODULE_AUTHOR("Texas Instruments Inc.");
 MODULE_LICENSE("GPL v2");
	// SPDX-License-Identifier: GPL-2.0
	/*
	* Copyright (C) 2016-2017 Texas Instruments Incorporated - http://www.ti.com/
	* Nishanth Menon <nm@ti.com>
	* Dave Gerlach <d-gerlach@ti.com>
	*
	* TI OPP supply driver that provides override into the regulator control
	* for generic opp core to handle devices with ABB regulator and/or
	* SmartReflex Class0.
	*/
	#include <linux/clk.h>
	#include <linux/cpufreq.h>
	#include <linux/device.h>
	#include <linux/io.h>
	#include <linux/module.h>
	#include <linux/notifier.h>
	#include <linux/of_device.h>
	#include <linux/of.h>
	#include <linux/platform_device.h>
	#include <linux/pm_opp.h>
	#include <linux/regulator/consumer.h>
	#include <linux/slab.h>

	/**
	* struct ti_opp_supply_optimum_voltage_table - optimized voltage table
	* @reference_uv: reference voltage (usually Nominal voltage)
	* @optimized_uv: Optimized voltage from efuse
	*/
	struct ti_opp_supply_optimum_voltage_table {
	unsigned int reference_uv;
	unsigned int optimized_uv;
	};

	/**
	* struct ti_opp_supply_data - OMAP specific opp supply data
	* @vdd_table: Optimized voltage mapping table
	* @num_vdd_table: number of entries in vdd_table
	* @vdd_absolute_max_voltage_uv: absolute maximum voltage in UV for the supply
	*/
	struct ti_opp_supply_data {
	struct ti_opp_supply_optimum_voltage_table *vdd_table;
	u32 num_vdd_table;
	u32 vdd_absolute_max_voltage_uv;
	};

	static struct ti_opp_supply_data opp_data;

	/**
	* struct ti_opp_supply_of_data - device tree match data
	* @flags: specific type of opp supply
	* @efuse_voltage_mask: mask required for efuse register representing voltage
	* @efuse_voltage_uv: Are the efuse entries in micro-volts? if not, assume
	* milli-volts.
	*/
	struct ti_opp_supply_of_data {
	#define OPPDM_EFUSE_CLASS0_OPTIMIZED_VOLTAGE BIT(1)
	#define OPPDM_HAS_NO_ABB BIT(2)
	const u8 flags;
	const u32 efuse_voltage_mask;
	const bool efuse_voltage_uv;
	};

	/**
	* _store_optimized_voltages() - store optimized voltages
	* @dev: ti opp supply device for which we need to store info
	* @data: data specific to the device
	*
	* Picks up efuse based optimized voltages for VDD unique per device and
	* stores it in internal data structure for use during transition requests.
	*
	* Return: If successful, 0, else appropriate error value.
	*/
	static int _store_optimized_voltages(struct device *dev,
	struct ti_opp_supply_data *data)
	{
	void __iomem *base;
	struct property *prop;
	struct resource *res;
	const __be32 *val;
	int proplen, i;
	int ret = 0;
	struct ti_opp_supply_optimum_voltage_table *table;
	const struct ti_opp_supply_of_data *of_data = dev_get_drvdata(dev);

	/* pick up Efuse based voltages */
	res = platform_get_resource(to_platform_device(dev), IORESOURCE_MEM, 0);
	if (!res) {
	dev_err(dev, "Unable to get IO resource\n");
	ret = -ENODEV;
	goto out_map;
	}

	base = ioremap(res->start, resource_size(res));
	if (!base) {
	dev_err(dev, "Unable to map Efuse registers\n");
	ret = -ENOMEM;
	goto out_map;
	}

	/* Fetch efuse-settings. */
	prop = of_find_property(dev->of_node, "ti,efuse-settings", NULL);
	if (!prop) {
	dev_err(dev, "No 'ti,efuse-settings' property found\n");
	ret = -EINVAL;
	goto out;
	}

	proplen = prop->length / sizeof(int);
	data->num_vdd_table = proplen / 2;
	/* Verify for corrupted OPP entries in dt */
	if (data->num_vdd_table * 2 * sizeof(int) != prop->length) {
	dev_err(dev, "Invalid 'ti,efuse-settings'\n");
	ret = -EINVAL;
	goto out;
	}

	ret = of_property_read_u32(dev->of_node, "ti,absolute-max-voltage-uv",
	&data->vdd_absolute_max_voltage_uv);
	if (ret) {
	dev_err(dev, "ti,absolute-max-voltage-uv is missing\n");
	ret = -EINVAL;
	goto out;
	}

	table = kcalloc(data->num_vdd_table, sizeof(*data->vdd_table),
	GFP_KERNEL);
	if (!table) {
	ret = -ENOMEM;
	goto out;
	}
	data->vdd_table = table;

	val = prop->value;
	for (i = 0; i < data->num_vdd_table; i++, table++) {
	u32 efuse_offset;
	u32 tmp;

	table->reference_uv = be32_to_cpup(val++);
	efuse_offset = be32_to_cpup(val++);

	tmp = readl(base + efuse_offset);
	tmp &= of_data->efuse_voltage_mask;
	tmp >>= __ffs(of_data->efuse_voltage_mask);

	table->optimized_uv = of_data->efuse_voltage_uv ? tmp :
	tmp * 1000;

	dev_dbg(dev, "[%d] efuse=0x%08x volt_table=%d vset=%d\n",
	i, efuse_offset, table->reference_uv,
	table->optimized_uv);

	/*
	* Some older samples might not have optimized efuse
	* Use reference voltage for those - just add debug message
	* for them.
	*/
	if (!table->optimized_uv) {
	dev_dbg(dev, "[%d] efuse=0x%08x volt_table=%d:vset0\n",
	i, efuse_offset, table->reference_uv);
	table->optimized_uv = table->reference_uv;
	}
	}
	out:
	iounmap(base);
	out_map:
	return ret;
	}

	/**
	* _free_optimized_voltages() - free resources for optvoltages
	* @dev: device for which we need to free info
	* @data: data specific to the device
	*/
	static void _free_optimized_voltages(struct device *dev,
	struct ti_opp_supply_data *data)
	{
	kfree(data->vdd_table);
	data->vdd_table = NULL;
	data->num_vdd_table = 0;
	}

	/**
	* _get_optimal_vdd_voltage() - Finds optimal voltage for the supply
	* @dev: device for which we need to find info
	* @data: data specific to the device
	* @reference_uv: reference voltage (OPP voltage) for which we need value
	*
	* Return: if a match is found, return optimized voltage, else return
	* reference_uv, also return reference_uv if no optimization is needed.
	*/
	static int _get_optimal_vdd_voltage(struct device *dev,
	struct ti_opp_supply_data *data,
	int reference_uv)
	{
	int i;
	struct ti_opp_supply_optimum_voltage_table *table;

	if (!data->num_vdd_table)
	return reference_uv;

	table = data->vdd_table;
	if (!table)
	return -EINVAL;

	/* Find a exact match - this list is usually very small */
	for (i = 0; i < data->num_vdd_table; i++, table++)
	if (table->reference_uv == reference_uv)
	return table->optimized_uv;

	/* IF things are screwed up, we'd make a mess on console.. ratelimit */
	dev_err_ratelimited(dev, "%s: Failed optimized voltage match for %d\n",
	__func__, reference_uv);
	return reference_uv;
	}

	static int _opp_set_voltage(struct device *dev,
	struct dev_pm_opp_supply *supply,
	int new_target_uv, struct regulator *reg,
	char *reg_name)
	{
	int ret;
	unsigned long vdd_uv, uv_max;

	if (new_target_uv)
	vdd_uv = new_target_uv;
	else
	vdd_uv = supply->u_volt;

	/*
	* If we do have an absolute max voltage specified, then we should
	* use that voltage instead to allow for cases where the voltage rails
	* are ganged (example if we set the max for an opp as 1.12v, and
	* the absolute max is 1.5v, for another rail to get 1.25v, it cannot
	* be achieved if the regulator is constrainted to max of 1.12v, even
	* if it can function at 1.25v
	*/
	if (opp_data.vdd_absolute_max_voltage_uv)
	uv_max = opp_data.vdd_absolute_max_voltage_uv;
	else
	uv_max = supply->u_volt_max;

	if (vdd_uv > uv_max \|\|
	vdd_uv < supply->u_volt_min \|\|
	supply->u_volt_min > uv_max) {
	dev_warn(dev,
	"Invalid range voltages [Min:%lu target:%lu Max:%lu]\n",
	supply->u_volt_min, vdd_uv, uv_max);
	return -EINVAL;
	}

	dev_dbg(dev, "%s scaling to %luuV[min %luuV max %luuV]\n", reg_name,
	vdd_uv, supply->u_volt_min,
	uv_max);

	ret = regulator_set_voltage_triplet(reg,
	supply->u_volt_min,
	vdd_uv,
	uv_max);
	if (ret) {
	dev_err(dev, "%s failed for %luuV[min %luuV max %luuV]\n",
	reg_name, vdd_uv, supply->u_volt_min,
	uv_max);
	return ret;
	}

	return 0;
	}

	/**
	* ti_opp_supply_set_opp() - do the opp supply transition
	* @data: information on regulators and new and old opps provided by
	* opp core to use in transition
	*
	* Return: If successful, 0, else appropriate error value.
	*/
	static int ti_opp_supply_set_opp(struct dev_pm_set_opp_data *data)
	{
	struct dev_pm_opp_supply *old_supply_vdd = &data->old_opp.supplies[0];
	struct dev_pm_opp_supply *old_supply_vbb = &data->old_opp.supplies[1];
	struct dev_pm_opp_supply *new_supply_vdd = &data->new_opp.supplies[0];
	struct dev_pm_opp_supply *new_supply_vbb = &data->new_opp.supplies[1];
	struct device *dev = data->dev;
	unsigned long old_freq = data->old_opp.rate, freq = data->new_opp.rate;
	struct clk *clk = data->clk;
	struct regulator *vdd_reg = data->regulators[0];
	struct regulator *vbb_reg = data->regulators[1];
	int vdd_uv;
	int ret;

	vdd_uv = _get_optimal_vdd_voltage(dev, &opp_data,
	new_supply_vdd->u_volt);

	if (new_supply_vdd->u_volt_min < vdd_uv)
	new_supply_vdd->u_volt_min = vdd_uv;

	/* Scaling up? Scale voltage before frequency */
	if (freq > old_freq) {
	ret = _opp_set_voltage(dev, new_supply_vdd, vdd_uv, vdd_reg,
	"vdd");
	if (ret)
	goto restore_voltage;

	ret = _opp_set_voltage(dev, new_supply_vbb, 0, vbb_reg, "vbb");
	if (ret)
	goto restore_voltage;
	}

	/* Change frequency */
	dev_dbg(dev, "%s: switching OPP: %lu Hz --> %lu Hz\n",
	__func__, old_freq, freq);

	ret = clk_set_rate(clk, freq);
	if (ret) {
	dev_err(dev, "%s: failed to set clock rate: %d\n", __func__,
	ret);
	goto restore_voltage;
	}

	/* Scaling down? Scale voltage after frequency */
	if (freq < old_freq) {
	ret = _opp_set_voltage(dev, new_supply_vbb, 0, vbb_reg, "vbb");
	if (ret)
	goto restore_freq;

	ret = _opp_set_voltage(dev, new_supply_vdd, vdd_uv, vdd_reg,
	"vdd");
	if (ret)
	goto restore_freq;
	}

	return 0;

	restore_freq:
	ret = clk_set_rate(clk, old_freq);
	if (ret)
	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_vdd->u_volt) {
	ret = _opp_set_voltage(dev, old_supply_vbb, 0, vbb_reg, "vbb");
	if (ret)
	return ret;

	ret = _opp_set_voltage(dev, old_supply_vdd, 0, vdd_reg,
	"vdd");
	if (ret)
	return ret;
	}

	return ret;
	}

	static const struct ti_opp_supply_of_data omap_generic_of_data = {
	};

	static const struct ti_opp_supply_of_data omap_omap5_of_data = {
	.flags = OPPDM_EFUSE_CLASS0_OPTIMIZED_VOLTAGE,
	.efuse_voltage_mask = 0xFFF,
	.efuse_voltage_uv = false,
	};

	static const struct ti_opp_supply_of_data omap_omap5core_of_data = {
	.flags = OPPDM_EFUSE_CLASS0_OPTIMIZED_VOLTAGE \| OPPDM_HAS_NO_ABB,
	.efuse_voltage_mask = 0xFFF,
	.efuse_voltage_uv = false,
	};

	static const struct of_device_id ti_opp_supply_of_match[] = {
	{.compatible = "ti,omap-opp-supply", .data = &omap_generic_of_data},
	{.compatible = "ti,omap5-opp-supply", .data = &omap_omap5_of_data},
	{.compatible = "ti,omap5-core-opp-supply",
	.data = &omap_omap5core_of_data},
	{},
	};
	MODULE_DEVICE_TABLE(of, ti_opp_supply_of_match);

	static int ti_opp_supply_probe(struct platform_device *pdev)
	{
	struct device *dev = &pdev->dev;
	struct device *cpu_dev = get_cpu_device(0);
	const struct of_device_id *match;
	const struct ti_opp_supply_of_data *of_data;
	int ret = 0;

	match = of_match_device(ti_opp_supply_of_match, dev);
	if (!match) {
	/* We do not expect this to happen */
	dev_err(dev, "%s: Unable to match device\n", __func__);
	return -ENODEV;
	}
	if (!match->data) {
	/* Again, unlikely.. but mistakes do happen */
	dev_err(dev, "%s: Bad data in match\n", __func__);
	return -EINVAL;
	}
	of_data = match->data;

	dev_set_drvdata(dev, (void *)of_data);

	/* If we need optimized voltage */
	if (of_data->flags & OPPDM_EFUSE_CLASS0_OPTIMIZED_VOLTAGE) {
	ret = _store_optimized_voltages(dev, &opp_data);
	if (ret)
	return ret;
	}

	ret = PTR_ERR_OR_ZERO(dev_pm_opp_register_set_opp_helper(cpu_dev,
	ti_opp_supply_set_opp));
	if (ret)
	_free_optimized_voltages(dev, &opp_data);

	return ret;
	}

	static struct platform_driver ti_opp_supply_driver = {
	.probe = ti_opp_supply_probe,
	.driver = {
	.name = "ti_opp_supply",
	.of_match_table = of_match_ptr(ti_opp_supply_of_match),
	},
	};
	module_platform_driver(ti_opp_supply_driver);

	MODULE_DESCRIPTION("Texas Instruments OMAP OPP Supply driver");
	MODULE_AUTHOR("Texas Instruments Inc.");
	MODULE_LICENSE("GPL v2");