drivers/regulator/max8660.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * max8660.c  --  Voltage regulation for the Maxim 8660/8661
  *
  * based on max1586.c and wm8400-regulator.c
  *
  * Copyright (C) 2009 Wolfram Sang, Pengutronix e.K.
  *
  * Some info:
  *
  * Datasheet: http://datasheets.maxim-ic.com/en/ds/MAX8660-MAX8661.pdf
  *
  * This chip is a bit nasty because it is a write-only device. Thus, the driver
  * uses shadow registers to keep track of its values. The main problem appears
  * to be the initialization: When Linux boots up, we cannot know if the chip is
  * in the default state or not, so we would have to pass such information in
  * platform_data. As this adds a bit of complexity to the driver, this is left
  * out for now until it is really needed.
  *
  * [A|S|M]DTV1 registers are currently not used, but [A|S|M]DTV2.
  *
  * If the driver is feature complete, it might be worth to check if one set of
  * functions for V3-V7 is sufficient. For maximum flexibility during
  * development, they are separated for now.
  */

 #include <linux/module.h>
 #include <linux/err.h>
 #include <linux/i2c.h>
 #include <linux/platform_device.h>
 #include <linux/regulator/driver.h>
 #include <linux/slab.h>
 #include <linux/regulator/max8660.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
 #include <linux/regulator/of_regulator.h>

 #define MAX8660_DCDC_MIN_UV	 725000
 #define MAX8660_DCDC_MAX_UV	1800000
 #define MAX8660_DCDC_STEP	  25000
 #define MAX8660_DCDC_MAX_SEL	0x2b

 #define MAX8660_LDO5_MIN_UV	1700000
 #define MAX8660_LDO5_MAX_UV	2000000
 #define MAX8660_LDO5_STEP	  25000
 #define MAX8660_LDO5_MAX_SEL	0x0c

 #define MAX8660_LDO67_MIN_UV	1800000
 #define MAX8660_LDO67_MAX_UV	3300000
 #define MAX8660_LDO67_STEP	 100000
 #define MAX8660_LDO67_MAX_SEL	0x0f

 enum {
 	MAX8660_OVER1,
 	MAX8660_OVER2,
 	MAX8660_VCC1,
 	MAX8660_ADTV1,
 	MAX8660_ADTV2,
 	MAX8660_SDTV1,
 	MAX8660_SDTV2,
 	MAX8660_MDTV1,
 	MAX8660_MDTV2,
 	MAX8660_L12VCR,
 	MAX8660_FPWM,
 	MAX8660_N_REGS,	/* not a real register */
 };

 struct max8660 {
 	struct i2c_client *client;
 	u8 shadow_regs[MAX8660_N_REGS];		/* as chip is write only */
 };

 static int max8660_write(struct max8660 *max8660, u8 reg, u8 mask, u8 val)
 {
 	static const u8 max8660_addresses[MAX8660_N_REGS] = {
 	 0x10, 0x12, 0x20, 0x23, 0x24, 0x29, 0x2a, 0x32, 0x33, 0x39, 0x80
 	};

 	int ret;
 	u8 reg_val = (max8660->shadow_regs[reg] & mask) | val;

 	dev_vdbg(&max8660->client->dev, "Writing reg %02x with %02x\n",
 			max8660_addresses[reg], reg_val);

 	ret = i2c_smbus_write_byte_data(max8660->client,
 			max8660_addresses[reg], reg_val);
 	if (ret == 0)
 		max8660->shadow_regs[reg] = reg_val;

 	return ret;
 }


 /*
  * DCDC functions
  */

 static int max8660_dcdc_is_enabled(struct regulator_dev *rdev)
 {
 	struct max8660 *max8660 = rdev_get_drvdata(rdev);
 	u8 val = max8660->shadow_regs[MAX8660_OVER1];
 	u8 mask = (rdev_get_id(rdev) == MAX8660_V3) ? 1 : 4;

 	return !!(val & mask);
 }

 static int max8660_dcdc_enable(struct regulator_dev *rdev)
 {
 	struct max8660 *max8660 = rdev_get_drvdata(rdev);
 	u8 bit = (rdev_get_id(rdev) == MAX8660_V3) ? 1 : 4;

 	return max8660_write(max8660, MAX8660_OVER1, 0xff, bit);
 }

 static int max8660_dcdc_disable(struct regulator_dev *rdev)
 {
 	struct max8660 *max8660 = rdev_get_drvdata(rdev);
 	u8 mask = (rdev_get_id(rdev) == MAX8660_V3) ? ~1 : ~4;

 	return max8660_write(max8660, MAX8660_OVER1, mask, 0);
 }

 static int max8660_dcdc_get_voltage_sel(struct regulator_dev *rdev)
 {
 	struct max8660 *max8660 = rdev_get_drvdata(rdev);
 	u8 reg = (rdev_get_id(rdev) == MAX8660_V3) ? MAX8660_ADTV2 : MAX8660_SDTV2;
 	u8 selector = max8660->shadow_regs[reg];

 	return selector;
 }

 static int max8660_dcdc_set_voltage_sel(struct regulator_dev *rdev,
 					unsigned int selector)
 {
 	struct max8660 *max8660 = rdev_get_drvdata(rdev);
 	u8 reg, bits;
 	int ret;

 	reg = (rdev_get_id(rdev) == MAX8660_V3) ? MAX8660_ADTV2 : MAX8660_SDTV2;
 	ret = max8660_write(max8660, reg, 0, selector);
 	if (ret)
 		return ret;

 	/* Select target voltage register and activate regulation */
 	bits = (rdev_get_id(rdev) == MAX8660_V3) ? 0x03 : 0x30;
 	return max8660_write(max8660, MAX8660_VCC1, 0xff, bits);
 }

 static struct regulator_ops max8660_dcdc_ops = {
 	.is_enabled = max8660_dcdc_is_enabled,
 	.list_voltage = regulator_list_voltage_linear,
 	.map_voltage = regulator_map_voltage_linear,
 	.set_voltage_sel = max8660_dcdc_set_voltage_sel,
 	.get_voltage_sel = max8660_dcdc_get_voltage_sel,
 };


 /*
  * LDO5 functions
  */

 static int max8660_ldo5_get_voltage_sel(struct regulator_dev *rdev)
 {
 	struct max8660 *max8660 = rdev_get_drvdata(rdev);

 	u8 selector = max8660->shadow_regs[MAX8660_MDTV2];
 	return selector;
 }

 static int max8660_ldo5_set_voltage_sel(struct regulator_dev *rdev,
 					unsigned int selector)
 {
 	struct max8660 *max8660 = rdev_get_drvdata(rdev);
 	int ret;

 	ret = max8660_write(max8660, MAX8660_MDTV2, 0, selector);
 	if (ret)
 		return ret;

 	/* Select target voltage register and activate regulation */
 	return max8660_write(max8660, MAX8660_VCC1, 0xff, 0xc0);
 }

 static const struct regulator_ops max8660_ldo5_ops = {
 	.list_voltage = regulator_list_voltage_linear,
 	.map_voltage = regulator_map_voltage_linear,
 	.set_voltage_sel = max8660_ldo5_set_voltage_sel,
 	.get_voltage_sel = max8660_ldo5_get_voltage_sel,
 };


 /*
  * LDO67 functions
  */

 static int max8660_ldo67_is_enabled(struct regulator_dev *rdev)
 {
 	struct max8660 *max8660 = rdev_get_drvdata(rdev);
 	u8 val = max8660->shadow_regs[MAX8660_OVER2];
 	u8 mask = (rdev_get_id(rdev) == MAX8660_V6) ? 2 : 4;

 	return !!(val & mask);
 }

 static int max8660_ldo67_enable(struct regulator_dev *rdev)
 {
 	struct max8660 *max8660 = rdev_get_drvdata(rdev);
 	u8 bit = (rdev_get_id(rdev) == MAX8660_V6) ? 2 : 4;

 	return max8660_write(max8660, MAX8660_OVER2, 0xff, bit);
 }

 static int max8660_ldo67_disable(struct regulator_dev *rdev)
 {
 	struct max8660 *max8660 = rdev_get_drvdata(rdev);
 	u8 mask = (rdev_get_id(rdev) == MAX8660_V6) ? ~2 : ~4;

 	return max8660_write(max8660, MAX8660_OVER2, mask, 0);
 }

 static int max8660_ldo67_get_voltage_sel(struct regulator_dev *rdev)
 {
 	struct max8660 *max8660 = rdev_get_drvdata(rdev);
 	u8 shift = (rdev_get_id(rdev) == MAX8660_V6) ? 0 : 4;
 	u8 selector = (max8660->shadow_regs[MAX8660_L12VCR] >> shift) & 0xf;

 	return selector;
 }

 static int max8660_ldo67_set_voltage_sel(struct regulator_dev *rdev,
 					 unsigned int selector)
 {
 	struct max8660 *max8660 = rdev_get_drvdata(rdev);

 	if (rdev_get_id(rdev) == MAX8660_V6)
 		return max8660_write(max8660, MAX8660_L12VCR, 0xf0, selector);
 	else
 		return max8660_write(max8660, MAX8660_L12VCR, 0x0f,
 				     selector << 4);
 }

 static const struct regulator_ops max8660_ldo67_ops = {
 	.is_enabled = max8660_ldo67_is_enabled,
 	.enable = max8660_ldo67_enable,
 	.disable = max8660_ldo67_disable,
 	.list_voltage = regulator_list_voltage_linear,
 	.map_voltage = regulator_map_voltage_linear,
 	.get_voltage_sel = max8660_ldo67_get_voltage_sel,
 	.set_voltage_sel = max8660_ldo67_set_voltage_sel,
 };

 static const struct regulator_desc max8660_reg[] = {
 	{
 		.name = "V3(DCDC)",
 		.id = MAX8660_V3,
 		.ops = &max8660_dcdc_ops,
 		.type = REGULATOR_VOLTAGE,
 		.n_voltages = MAX8660_DCDC_MAX_SEL + 1,
 		.owner = THIS_MODULE,
 		.min_uV = MAX8660_DCDC_MIN_UV,
 		.uV_step = MAX8660_DCDC_STEP,
 	},
 	{
 		.name = "V4(DCDC)",
 		.id = MAX8660_V4,
 		.ops = &max8660_dcdc_ops,
 		.type = REGULATOR_VOLTAGE,
 		.n_voltages = MAX8660_DCDC_MAX_SEL + 1,
 		.owner = THIS_MODULE,
 		.min_uV = MAX8660_DCDC_MIN_UV,
 		.uV_step = MAX8660_DCDC_STEP,
 	},
 	{
 		.name = "V5(LDO)",
 		.id = MAX8660_V5,
 		.ops = &max8660_ldo5_ops,
 		.type = REGULATOR_VOLTAGE,
 		.n_voltages = MAX8660_LDO5_MAX_SEL + 1,
 		.owner = THIS_MODULE,
 		.min_uV = MAX8660_LDO5_MIN_UV,
 		.uV_step = MAX8660_LDO5_STEP,
 	},
 	{
 		.name = "V6(LDO)",
 		.id = MAX8660_V6,
 		.ops = &max8660_ldo67_ops,
 		.type = REGULATOR_VOLTAGE,
 		.n_voltages = MAX8660_LDO67_MAX_SEL + 1,
 		.owner = THIS_MODULE,
 		.min_uV = MAX8660_LDO67_MIN_UV,
 		.uV_step = MAX8660_LDO67_STEP,
 	},
 	{
 		.name = "V7(LDO)",
 		.id = MAX8660_V7,
 		.ops = &max8660_ldo67_ops,
 		.type = REGULATOR_VOLTAGE,
 		.n_voltages = MAX8660_LDO67_MAX_SEL + 1,
 		.owner = THIS_MODULE,
 		.min_uV = MAX8660_LDO67_MIN_UV,
 		.uV_step = MAX8660_LDO67_STEP,
 	},
 };

 enum {
 	MAX8660 = 0,
 	MAX8661 = 1,
 };

 #ifdef CONFIG_OF
 static const struct of_device_id max8660_dt_ids[] = {
 	{ .compatible = "maxim,max8660", .data = (void *) MAX8660 },
 	{ .compatible = "maxim,max8661", .data = (void *) MAX8661 },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, max8660_dt_ids);

 static int max8660_pdata_from_dt(struct device *dev,
 				 struct device_node **of_node,
 				 struct max8660_platform_data *pdata)
 {
 	int matched, i;
 	struct device_node *np;
 	struct max8660_subdev_data *sub;
 	struct of_regulator_match rmatch[ARRAY_SIZE(max8660_reg)] = { };

 	np = of_get_child_by_name(dev->of_node, "regulators");
 	if (!np) {
 		dev_err(dev, "missing 'regulators' subnode in DT\n");
 		return -EINVAL;
 	}

 	for (i = 0; i < ARRAY_SIZE(rmatch); i++)
 		rmatch[i].name = max8660_reg[i].name;

 	matched = of_regulator_match(dev, np, rmatch, ARRAY_SIZE(rmatch));
 	of_node_put(np);
 	if (matched <= 0)
 		return matched;

 	pdata->subdevs = devm_kcalloc(dev,
 				      matched,
 				      sizeof(struct max8660_subdev_data),
 				      GFP_KERNEL);
 	if (!pdata->subdevs)
 		return -ENOMEM;

 	pdata->num_subdevs = matched;
 	sub = pdata->subdevs;

 	for (i = 0; i < matched; i++) {
 		sub->id = i;
 		sub->name = rmatch[i].name;
 		sub->platform_data = rmatch[i].init_data;
 		of_node[i] = rmatch[i].of_node;
 		sub++;
 	}

 	return 0;
 }
 #else
 static inline int max8660_pdata_from_dt(struct device *dev,
 					struct device_node **of_node,
 					struct max8660_platform_data *pdata)
 {
 	return 0;
 }
 #endif

 static int max8660_probe(struct i2c_client *client)
 {
 	const struct i2c_device_id *i2c_id = i2c_client_get_device_id(client);
 	struct device *dev = &client->dev;
 	struct max8660_platform_data pdata_of, *pdata = dev_get_platdata(dev);
 	struct regulator_config config = { };
 	struct max8660 *max8660;
 	int boot_on, i, id, ret = -EINVAL;
 	struct device_node *of_node[MAX8660_V_END];
 	unsigned long type;

 	if (dev->of_node && !pdata) {
 		const struct of_device_id *id;

 		id = of_match_device(of_match_ptr(max8660_dt_ids), dev);
 		if (!id)
 			return -ENODEV;

 		ret = max8660_pdata_from_dt(dev, of_node, &pdata_of);
 		if (ret < 0)
 			return ret;

 		pdata = &pdata_of;
 		type = (unsigned long) id->data;
 	} else {
 		type = i2c_id->driver_data;
 		memset(of_node, 0, sizeof(of_node));
 	}

 	if (pdata->num_subdevs > MAX8660_V_END) {
 		dev_err(dev, "Too many regulators found!\n");
 		return -EINVAL;
 	}

 	max8660 = devm_kzalloc(dev, sizeof(struct max8660), GFP_KERNEL);
 	if (!max8660)
 		return -ENOMEM;

 	max8660->client = client;

 	if (pdata->en34_is_high) {
 		/* Simulate always on */
 		max8660->shadow_regs[MAX8660_OVER1] = 5;
 	} else {
 		/* Otherwise devices can be toggled via software */
 		max8660_dcdc_ops.enable = max8660_dcdc_enable;
 		max8660_dcdc_ops.disable = max8660_dcdc_disable;
 	}

 	/*
 	 * First, set up shadow registers to prevent glitches. As some
 	 * registers are shared between regulators, everything must be properly
 	 * set up for all regulators in advance.
 	 */
 	max8660->shadow_regs[MAX8660_ADTV1] =
 		max8660->shadow_regs[MAX8660_ADTV2] =
 		max8660->shadow_regs[MAX8660_SDTV1] =
 		max8660->shadow_regs[MAX8660_SDTV2] = 0x1b;
 	max8660->shadow_regs[MAX8660_MDTV1] =
 		max8660->shadow_regs[MAX8660_MDTV2] = 0x04;

 	for (i = 0; i < pdata->num_subdevs; i++) {

 		if (!pdata->subdevs[i].platform_data)
 			boot_on = false;
 		else
 			boot_on = pdata->subdevs[i].platform_data->constraints.boot_on;

 		switch (pdata->subdevs[i].id) {
 		case MAX8660_V3:
 			if (boot_on)
 				max8660->shadow_regs[MAX8660_OVER1] |= 1;
 			break;

 		case MAX8660_V4:
 			if (boot_on)
 				max8660->shadow_regs[MAX8660_OVER1] |= 4;
 			break;

 		case MAX8660_V5:
 			break;

 		case MAX8660_V6:
 			if (boot_on)
 				max8660->shadow_regs[MAX8660_OVER2] |= 2;
 			break;

 		case MAX8660_V7:
 			if (type == MAX8661) {
 				dev_err(dev, "Regulator not on this chip!\n");
 				return -EINVAL;
 			}

 			if (boot_on)
 				max8660->shadow_regs[MAX8660_OVER2] |= 4;
 			break;

 		default:
 			dev_err(dev, "invalid regulator %s\n",
 				 pdata->subdevs[i].name);
 			return ret;
 		}
 	}

 	/* Finally register devices */
 	for (i = 0; i < pdata->num_subdevs; i++) {
 		struct regulator_dev *rdev;

 		id = pdata->subdevs[i].id;

 		config.dev = dev;
 		config.init_data = pdata->subdevs[i].platform_data;
 		config.of_node = of_node[i];
 		config.driver_data = max8660;

 		rdev = devm_regulator_register(&client->dev,
 						  &max8660_reg[id], &config);
 		if (IS_ERR(rdev)) {
 			dev_err(&client->dev, "failed to register %s\n",
 				max8660_reg[id].name);
 			return PTR_ERR(rdev);
 		}
 	}

 	i2c_set_clientdata(client, max8660);
 	return 0;
 }

 static const struct i2c_device_id max8660_id[] = {
 	{ .name = "max8660", .driver_data = MAX8660 },
 	{ .name = "max8661", .driver_data = MAX8661 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, max8660_id);

 static struct i2c_driver max8660_driver = {
 	.probe_new = max8660_probe,
 	.driver		= {
 		.name	= "max8660",
 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
 	},
 	.id_table	= max8660_id,
 };

 static int __init max8660_init(void)
 {
 	return i2c_add_driver(&max8660_driver);
 }
 subsys_initcall(max8660_init);

 static void __exit max8660_exit(void)
 {
 	i2c_del_driver(&max8660_driver);
 }
 module_exit(max8660_exit);

 /* Module information */
 MODULE_DESCRIPTION("MAXIM 8660/8661 voltage regulator driver");
 MODULE_AUTHOR("Wolfram Sang");
 MODULE_LICENSE("GPL v2");
	// SPDX-License-Identifier: GPL-2.0-only
	/*
	* max8660.c -- Voltage regulation for the Maxim 8660/8661
	*
	* based on max1586.c and wm8400-regulator.c
	*
	* Copyright (C) 2009 Wolfram Sang, Pengutronix e.K.
	*
	* Some info:
	*
	* Datasheet: http://datasheets.maxim-ic.com/en/ds/MAX8660-MAX8661.pdf
	*
	* This chip is a bit nasty because it is a write-only device. Thus, the driver
	* uses shadow registers to keep track of its values. The main problem appears
	* to be the initialization: When Linux boots up, we cannot know if the chip is
	* in the default state or not, so we would have to pass such information in
	* platform_data. As this adds a bit of complexity to the driver, this is left
	* out for now until it is really needed.
	*
	* [A\|S\|M]DTV1 registers are currently not used, but [A\|S\|M]DTV2.
	*
	* If the driver is feature complete, it might be worth to check if one set of
	* functions for V3-V7 is sufficient. For maximum flexibility during
	* development, they are separated for now.
	*/

	#include <linux/module.h>
	#include <linux/err.h>
	#include <linux/i2c.h>
	#include <linux/platform_device.h>
	#include <linux/regulator/driver.h>
	#include <linux/slab.h>
	#include <linux/regulator/max8660.h>
	#include <linux/of.h>
	#include <linux/of_device.h>
	#include <linux/regulator/of_regulator.h>

	#define MAX8660_DCDC_MIN_UV 725000
	#define MAX8660_DCDC_MAX_UV 1800000
	#define MAX8660_DCDC_STEP 25000
	#define MAX8660_DCDC_MAX_SEL 0x2b

	#define MAX8660_LDO5_MIN_UV 1700000
	#define MAX8660_LDO5_MAX_UV 2000000
	#define MAX8660_LDO5_STEP 25000
	#define MAX8660_LDO5_MAX_SEL 0x0c

	#define MAX8660_LDO67_MIN_UV 1800000
	#define MAX8660_LDO67_MAX_UV 3300000
	#define MAX8660_LDO67_STEP 100000
	#define MAX8660_LDO67_MAX_SEL 0x0f

	enum {
	MAX8660_OVER1,
	MAX8660_OVER2,
	MAX8660_VCC1,
	MAX8660_ADTV1,
	MAX8660_ADTV2,
	MAX8660_SDTV1,
	MAX8660_SDTV2,
	MAX8660_MDTV1,
	MAX8660_MDTV2,
	MAX8660_L12VCR,
	MAX8660_FPWM,
	MAX8660_N_REGS, /* not a real register */
	};

	struct max8660 {
	struct i2c_client *client;
	u8 shadow_regs[MAX8660_N_REGS]; /* as chip is write only */
	};

	static int max8660_write(struct max8660 *max8660, u8 reg, u8 mask, u8 val)
	{
	static const u8 max8660_addresses[MAX8660_N_REGS] = {
	0x10, 0x12, 0x20, 0x23, 0x24, 0x29, 0x2a, 0x32, 0x33, 0x39, 0x80
	};

	int ret;
	u8 reg_val = (max8660->shadow_regs[reg] & mask) \| val;

	dev_vdbg(&max8660->client->dev, "Writing reg %02x with %02x\n",
	max8660_addresses[reg], reg_val);

	ret = i2c_smbus_write_byte_data(max8660->client,
	max8660_addresses[reg], reg_val);
	if (ret == 0)
	max8660->shadow_regs[reg] = reg_val;

	return ret;
	}


	/*
	* DCDC functions
	*/

	static int max8660_dcdc_is_enabled(struct regulator_dev *rdev)
	{
	struct max8660 *max8660 = rdev_get_drvdata(rdev);
	u8 val = max8660->shadow_regs[MAX8660_OVER1];
	u8 mask = (rdev_get_id(rdev) == MAX8660_V3) ? 1 : 4;

	return !!(val & mask);
	}

	static int max8660_dcdc_enable(struct regulator_dev *rdev)
	{
	struct max8660 *max8660 = rdev_get_drvdata(rdev);
	u8 bit = (rdev_get_id(rdev) == MAX8660_V3) ? 1 : 4;

	return max8660_write(max8660, MAX8660_OVER1, 0xff, bit);
	}

	static int max8660_dcdc_disable(struct regulator_dev *rdev)
	{
	struct max8660 *max8660 = rdev_get_drvdata(rdev);
	u8 mask = (rdev_get_id(rdev) == MAX8660_V3) ? ~1 : ~4;

	return max8660_write(max8660, MAX8660_OVER1, mask, 0);
	}

	static int max8660_dcdc_get_voltage_sel(struct regulator_dev *rdev)
	{
	struct max8660 *max8660 = rdev_get_drvdata(rdev);
	u8 reg = (rdev_get_id(rdev) == MAX8660_V3) ? MAX8660_ADTV2 : MAX8660_SDTV2;
	u8 selector = max8660->shadow_regs[reg];

	return selector;
	}

	static int max8660_dcdc_set_voltage_sel(struct regulator_dev *rdev,
	unsigned int selector)
	{
	struct max8660 *max8660 = rdev_get_drvdata(rdev);
	u8 reg, bits;
	int ret;

	reg = (rdev_get_id(rdev) == MAX8660_V3) ? MAX8660_ADTV2 : MAX8660_SDTV2;
	ret = max8660_write(max8660, reg, 0, selector);
	if (ret)
	return ret;

	/* Select target voltage register and activate regulation */
	bits = (rdev_get_id(rdev) == MAX8660_V3) ? 0x03 : 0x30;
	return max8660_write(max8660, MAX8660_VCC1, 0xff, bits);
	}

	static struct regulator_ops max8660_dcdc_ops = {
	.is_enabled = max8660_dcdc_is_enabled,
	.list_voltage = regulator_list_voltage_linear,
	.map_voltage = regulator_map_voltage_linear,
	.set_voltage_sel = max8660_dcdc_set_voltage_sel,
	.get_voltage_sel = max8660_dcdc_get_voltage_sel,
	};


	/*
	* LDO5 functions
	*/

	static int max8660_ldo5_get_voltage_sel(struct regulator_dev *rdev)
	{
	struct max8660 *max8660 = rdev_get_drvdata(rdev);

	u8 selector = max8660->shadow_regs[MAX8660_MDTV2];
	return selector;
	}

	static int max8660_ldo5_set_voltage_sel(struct regulator_dev *rdev,
	unsigned int selector)
	{
	struct max8660 *max8660 = rdev_get_drvdata(rdev);
	int ret;

	ret = max8660_write(max8660, MAX8660_MDTV2, 0, selector);
	if (ret)
	return ret;

	/* Select target voltage register and activate regulation */
	return max8660_write(max8660, MAX8660_VCC1, 0xff, 0xc0);
	}

	static const struct regulator_ops max8660_ldo5_ops = {
	.list_voltage = regulator_list_voltage_linear,
	.map_voltage = regulator_map_voltage_linear,
	.set_voltage_sel = max8660_ldo5_set_voltage_sel,
	.get_voltage_sel = max8660_ldo5_get_voltage_sel,
	};


	/*
	* LDO67 functions
	*/

	static int max8660_ldo67_is_enabled(struct regulator_dev *rdev)
	{
	struct max8660 *max8660 = rdev_get_drvdata(rdev);
	u8 val = max8660->shadow_regs[MAX8660_OVER2];
	u8 mask = (rdev_get_id(rdev) == MAX8660_V6) ? 2 : 4;

	return !!(val & mask);
	}

	static int max8660_ldo67_enable(struct regulator_dev *rdev)
	{
	struct max8660 *max8660 = rdev_get_drvdata(rdev);
	u8 bit = (rdev_get_id(rdev) == MAX8660_V6) ? 2 : 4;

	return max8660_write(max8660, MAX8660_OVER2, 0xff, bit);
	}

	static int max8660_ldo67_disable(struct regulator_dev *rdev)
	{
	struct max8660 *max8660 = rdev_get_drvdata(rdev);
	u8 mask = (rdev_get_id(rdev) == MAX8660_V6) ? ~2 : ~4;

	return max8660_write(max8660, MAX8660_OVER2, mask, 0);
	}

	static int max8660_ldo67_get_voltage_sel(struct regulator_dev *rdev)
	{
	struct max8660 *max8660 = rdev_get_drvdata(rdev);
	u8 shift = (rdev_get_id(rdev) == MAX8660_V6) ? 0 : 4;
	u8 selector = (max8660->shadow_regs[MAX8660_L12VCR] >> shift) & 0xf;

	return selector;
	}

	static int max8660_ldo67_set_voltage_sel(struct regulator_dev *rdev,
	unsigned int selector)
	{
	struct max8660 *max8660 = rdev_get_drvdata(rdev);

	if (rdev_get_id(rdev) == MAX8660_V6)
	return max8660_write(max8660, MAX8660_L12VCR, 0xf0, selector);
	else
	return max8660_write(max8660, MAX8660_L12VCR, 0x0f,
	selector << 4);
	}

	static const struct regulator_ops max8660_ldo67_ops = {
	.is_enabled = max8660_ldo67_is_enabled,
	.enable = max8660_ldo67_enable,
	.disable = max8660_ldo67_disable,
	.list_voltage = regulator_list_voltage_linear,
	.map_voltage = regulator_map_voltage_linear,
	.get_voltage_sel = max8660_ldo67_get_voltage_sel,
	.set_voltage_sel = max8660_ldo67_set_voltage_sel,
	};

	static const struct regulator_desc max8660_reg[] = {
	{
	.name = "V3(DCDC)",
	.id = MAX8660_V3,
	.ops = &max8660_dcdc_ops,
	.type = REGULATOR_VOLTAGE,
	.n_voltages = MAX8660_DCDC_MAX_SEL + 1,
	.owner = THIS_MODULE,
	.min_uV = MAX8660_DCDC_MIN_UV,
	.uV_step = MAX8660_DCDC_STEP,
	},
	{
	.name = "V4(DCDC)",
	.id = MAX8660_V4,
	.ops = &max8660_dcdc_ops,
	.type = REGULATOR_VOLTAGE,
	.n_voltages = MAX8660_DCDC_MAX_SEL + 1,
	.owner = THIS_MODULE,
	.min_uV = MAX8660_DCDC_MIN_UV,
	.uV_step = MAX8660_DCDC_STEP,
	},
	{
	.name = "V5(LDO)",
	.id = MAX8660_V5,
	.ops = &max8660_ldo5_ops,
	.type = REGULATOR_VOLTAGE,
	.n_voltages = MAX8660_LDO5_MAX_SEL + 1,
	.owner = THIS_MODULE,
	.min_uV = MAX8660_LDO5_MIN_UV,
	.uV_step = MAX8660_LDO5_STEP,
	},
	{
	.name = "V6(LDO)",
	.id = MAX8660_V6,
	.ops = &max8660_ldo67_ops,
	.type = REGULATOR_VOLTAGE,
	.n_voltages = MAX8660_LDO67_MAX_SEL + 1,
	.owner = THIS_MODULE,
	.min_uV = MAX8660_LDO67_MIN_UV,
	.uV_step = MAX8660_LDO67_STEP,
	},
	{
	.name = "V7(LDO)",
	.id = MAX8660_V7,
	.ops = &max8660_ldo67_ops,
	.type = REGULATOR_VOLTAGE,
	.n_voltages = MAX8660_LDO67_MAX_SEL + 1,
	.owner = THIS_MODULE,
	.min_uV = MAX8660_LDO67_MIN_UV,
	.uV_step = MAX8660_LDO67_STEP,
	},
	};

	enum {
	MAX8660 = 0,
	MAX8661 = 1,
	};

	#ifdef CONFIG_OF
	static const struct of_device_id max8660_dt_ids[] = {
	{ .compatible = "maxim,max8660", .data = (void *) MAX8660 },
	{ .compatible = "maxim,max8661", .data = (void *) MAX8661 },
	{ }
	};
	MODULE_DEVICE_TABLE(of, max8660_dt_ids);

	static int max8660_pdata_from_dt(struct device *dev,
	struct device_node **of_node,
	struct max8660_platform_data *pdata)
	{
	int matched, i;
	struct device_node *np;
	struct max8660_subdev_data *sub;
	struct of_regulator_match rmatch[ARRAY_SIZE(max8660_reg)] = { };

	np = of_get_child_by_name(dev->of_node, "regulators");
	if (!np) {
	dev_err(dev, "missing 'regulators' subnode in DT\n");
	return -EINVAL;
	}

	for (i = 0; i < ARRAY_SIZE(rmatch); i++)
	rmatch[i].name = max8660_reg[i].name;

	matched = of_regulator_match(dev, np, rmatch, ARRAY_SIZE(rmatch));
	of_node_put(np);
	if (matched <= 0)
	return matched;

	pdata->subdevs = devm_kcalloc(dev,
	matched,
	sizeof(struct max8660_subdev_data),
	GFP_KERNEL);
	if (!pdata->subdevs)
	return -ENOMEM;

	pdata->num_subdevs = matched;
	sub = pdata->subdevs;

	for (i = 0; i < matched; i++) {
	sub->id = i;
	sub->name = rmatch[i].name;
	sub->platform_data = rmatch[i].init_data;
	of_node[i] = rmatch[i].of_node;
	sub++;
	}

	return 0;
	}
	#else
	static inline int max8660_pdata_from_dt(struct device *dev,
	struct device_node **of_node,
	struct max8660_platform_data *pdata)
	{
	return 0;
	}
	#endif

	static int max8660_probe(struct i2c_client *client)
	{
	const struct i2c_device_id *i2c_id = i2c_client_get_device_id(client);
	struct device *dev = &client->dev;
	struct max8660_platform_data pdata_of, *pdata = dev_get_platdata(dev);
	struct regulator_config config = { };
	struct max8660 *max8660;
	int boot_on, i, id, ret = -EINVAL;
	struct device_node *of_node[MAX8660_V_END];
	unsigned long type;

	if (dev->of_node && !pdata) {
	const struct of_device_id *id;

	id = of_match_device(of_match_ptr(max8660_dt_ids), dev);
	if (!id)
	return -ENODEV;

	ret = max8660_pdata_from_dt(dev, of_node, &pdata_of);
	if (ret < 0)
	return ret;

	pdata = &pdata_of;
	type = (unsigned long) id->data;
	} else {
	type = i2c_id->driver_data;
	memset(of_node, 0, sizeof(of_node));
	}

	if (pdata->num_subdevs > MAX8660_V_END) {
	dev_err(dev, "Too many regulators found!\n");
	return -EINVAL;
	}

	max8660 = devm_kzalloc(dev, sizeof(struct max8660), GFP_KERNEL);
	if (!max8660)
	return -ENOMEM;

	max8660->client = client;

	if (pdata->en34_is_high) {
	/* Simulate always on */
	max8660->shadow_regs[MAX8660_OVER1] = 5;
	} else {
	/* Otherwise devices can be toggled via software */
	max8660_dcdc_ops.enable = max8660_dcdc_enable;
	max8660_dcdc_ops.disable = max8660_dcdc_disable;
	}

	/*
	* First, set up shadow registers to prevent glitches. As some
	* registers are shared between regulators, everything must be properly
	* set up for all regulators in advance.
	*/
	max8660->shadow_regs[MAX8660_ADTV1] =
	max8660->shadow_regs[MAX8660_ADTV2] =
	max8660->shadow_regs[MAX8660_SDTV1] =
	max8660->shadow_regs[MAX8660_SDTV2] = 0x1b;
	max8660->shadow_regs[MAX8660_MDTV1] =
	max8660->shadow_regs[MAX8660_MDTV2] = 0x04;

	for (i = 0; i < pdata->num_subdevs; i++) {

	if (!pdata->subdevs[i].platform_data)
	boot_on = false;
	else
	boot_on = pdata->subdevs[i].platform_data->constraints.boot_on;

	switch (pdata->subdevs[i].id) {
	case MAX8660_V3:
	if (boot_on)
	max8660->shadow_regs[MAX8660_OVER1] \|= 1;
	break;

	case MAX8660_V4:
	if (boot_on)
	max8660->shadow_regs[MAX8660_OVER1] \|= 4;
	break;

	case MAX8660_V5:
	break;

	case MAX8660_V6:
	if (boot_on)
	max8660->shadow_regs[MAX8660_OVER2] \|= 2;
	break;

	case MAX8660_V7:
	if (type == MAX8661) {
	dev_err(dev, "Regulator not on this chip!\n");
	return -EINVAL;
	}

	if (boot_on)
	max8660->shadow_regs[MAX8660_OVER2] \|= 4;
	break;

	default:
	dev_err(dev, "invalid regulator %s\n",
	pdata->subdevs[i].name);
	return ret;
	}
	}

	/* Finally register devices */
	for (i = 0; i < pdata->num_subdevs; i++) {
	struct regulator_dev *rdev;

	id = pdata->subdevs[i].id;

	config.dev = dev;
	config.init_data = pdata->subdevs[i].platform_data;
	config.of_node = of_node[i];
	config.driver_data = max8660;

	rdev = devm_regulator_register(&client->dev,
	&max8660_reg[id], &config);
	if (IS_ERR(rdev)) {
	dev_err(&client->dev, "failed to register %s\n",
	max8660_reg[id].name);
	return PTR_ERR(rdev);
	}
	}

	i2c_set_clientdata(client, max8660);
	return 0;
	}

	static const struct i2c_device_id max8660_id[] = {
	{ .name = "max8660", .driver_data = MAX8660 },
	{ .name = "max8661", .driver_data = MAX8661 },
	{ }
	};
	MODULE_DEVICE_TABLE(i2c, max8660_id);

	static struct i2c_driver max8660_driver = {
	.probe_new = max8660_probe,
	.driver = {
	.name = "max8660",
	.probe_type = PROBE_PREFER_ASYNCHRONOUS,
	},
	.id_table = max8660_id,
	};

	static int __init max8660_init(void)
	{
	return i2c_add_driver(&max8660_driver);
	}
	subsys_initcall(max8660_init);

	static void __exit max8660_exit(void)
	{
	i2c_del_driver(&max8660_driver);
	}
	module_exit(max8660_exit);

	/* Module information */
	MODULE_DESCRIPTION("MAXIM 8660/8661 voltage regulator driver");
	MODULE_AUTHOR("Wolfram Sang");
	MODULE_LICENSE("GPL v2");