[linux-block.git] / drivers / regulator / max8952.c

/*
 * max8952.c - Voltage and current regulation for the Maxim 8952
 *
 * Copyright (C) 2010 Samsung Electronics
 * MyungJoo Ham <myungjoo.ham@samsung.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/i2c.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/max8952.h>
#include <linux/gpio.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_gpio.h>
#include <linux/regulator/of_regulator.h>
#include <linux/slab.h>

/* Registers */
enum {
	MAX8952_REG_MODE0,
	MAX8952_REG_MODE1,
	MAX8952_REG_MODE2,
	MAX8952_REG_MODE3,
	MAX8952_REG_CONTROL,
	MAX8952_REG_SYNC,
	MAX8952_REG_RAMP,
	MAX8952_REG_CHIP_ID1,
	MAX8952_REG_CHIP_ID2,
};

struct max8952_data {
	struct i2c_client	*client;
	struct device		*dev;
	struct max8952_platform_data *pdata;
	struct regulator_dev	*rdev;

	bool vid0;
	bool vid1;
};

static int max8952_read_reg(struct max8952_data *max8952, u8 reg)
{
	int ret = i2c_smbus_read_byte_data(max8952->client, reg);
	if (ret > 0)
		ret &= 0xff;

	return ret;
}

static int max8952_write_reg(struct max8952_data *max8952,
		u8 reg, u8 value)
{
	return i2c_smbus_write_byte_data(max8952->client, reg, value);
}

static int max8952_list_voltage(struct regulator_dev *rdev,
		unsigned int selector)
{
	struct max8952_data *max8952 = rdev_get_drvdata(rdev);

	if (rdev_get_id(rdev) != 0)
		return -EINVAL;

	return (max8952->pdata->dvs_mode[selector] * 10 + 770) * 1000;
}

static int max8952_get_voltage_sel(struct regulator_dev *rdev)
{
	struct max8952_data *max8952 = rdev_get_drvdata(rdev);
	u8 vid = 0;

	if (max8952->vid0)
		vid += 1;
	if (max8952->vid1)
		vid += 2;

	return vid;
}

static int max8952_set_voltage_sel(struct regulator_dev *rdev,
				   unsigned selector)
{
	struct max8952_data *max8952 = rdev_get_drvdata(rdev);

	if (!gpio_is_valid(max8952->pdata->gpio_vid0) ||
			!gpio_is_valid(max8952->pdata->gpio_vid1)) {
		/* DVS not supported */
		return -EPERM;
	}

	max8952->vid0 = selector & 0x1;
	max8952->vid1 = (selector >> 1) & 0x1;
	gpio_set_value(max8952->pdata->gpio_vid0, max8952->vid0);
	gpio_set_value(max8952->pdata->gpio_vid1, max8952->vid1);

	return 0;
}

static struct regulator_ops max8952_ops = {
	.list_voltage		= max8952_list_voltage,
	.get_voltage_sel	= max8952_get_voltage_sel,
	.set_voltage_sel	= max8952_set_voltage_sel,
};

static const struct regulator_desc regulator = {
	.name		= "MAX8952_VOUT",
	.id		= 0,
	.n_voltages	= MAX8952_NUM_DVS_MODE,
	.ops		= &max8952_ops,
	.type		= REGULATOR_VOLTAGE,
	.owner		= THIS_MODULE,
};

#ifdef CONFIG_OF
static struct of_device_id max8952_dt_match[] = {
	{ .compatible = "maxim,max8952" },
	{},
};
MODULE_DEVICE_TABLE(of, max8952_dt_match);

static struct max8952_platform_data *max8952_parse_dt(struct device *dev)
{
	struct max8952_platform_data *pd;
	struct device_node *np = dev->of_node;
	int ret;
	int i;

	pd = devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
	if (!pd) {
		dev_err(dev, "Failed to allocate platform data\n");
		return NULL;
	}

	pd->gpio_vid0 = of_get_named_gpio(np, "max8952,vid-gpios", 0);
	pd->gpio_vid1 = of_get_named_gpio(np, "max8952,vid-gpios", 1);
	pd->gpio_en = of_get_named_gpio(np, "max8952,en-gpio", 0);

	if (of_property_read_u32(np, "max8952,default-mode", &pd->default_mode))
		dev_warn(dev, "Default mode not specified, assuming 0\n");

	ret = of_property_read_u32_array(np, "max8952,dvs-mode-microvolt",
					pd->dvs_mode, ARRAY_SIZE(pd->dvs_mode));
	if (ret) {
		dev_err(dev, "max8952,dvs-mode-microvolt property not specified");
		return NULL;
	}

	for (i = 0; i < ARRAY_SIZE(pd->dvs_mode); ++i) {
		if (pd->dvs_mode[i] < 770000 || pd->dvs_mode[i] > 1400000) {
			dev_err(dev, "DVS voltage %d out of range\n", i);
			return NULL;
		}
		pd->dvs_mode[i] = (pd->dvs_mode[i] - 770000) / 10000;
	}

	if (of_property_read_u32(np, "max8952,sync-freq", &pd->sync_freq))
		dev_warn(dev, "max8952,sync-freq property not specified, defaulting to 26MHz\n");

	if (of_property_read_u32(np, "max8952,ramp-speed", &pd->ramp_speed))
		dev_warn(dev, "max8952,ramp-speed property not specified, defaulting to 32mV/us\n");

	pd->reg_data = of_get_regulator_init_data(dev, np);
	if (!pd->reg_data) {
		dev_err(dev, "Failed to parse regulator init data\n");
		return NULL;
	}

	return pd;
}
#else
static struct max8952_platform_data *max8952_parse_dt(struct device *dev)
{
	return NULL;
}
#endif

static int max8952_pmic_probe(struct i2c_client *client,
		const struct i2c_device_id *i2c_id)
{
	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
	struct max8952_platform_data *pdata = client->dev.platform_data;
	struct regulator_config config = { };
	struct max8952_data *max8952;

	int ret = 0, err = 0;

	if (client->dev.of_node)
		pdata = max8952_parse_dt(&client->dev);

	if (!pdata) {
		dev_err(&client->dev, "Require the platform data\n");
		return -EINVAL;
	}

	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE))
		return -EIO;

	max8952 = devm_kzalloc(&client->dev, sizeof(struct max8952_data),
			       GFP_KERNEL);
	if (!max8952)
		return -ENOMEM;

	max8952->client = client;
	max8952->dev = &client->dev;
	max8952->pdata = pdata;

	config.dev = max8952->dev;
	config.init_data = pdata->reg_data;
	config.driver_data = max8952;

	config.ena_gpio = pdata->gpio_en;
	if (pdata->reg_data->constraints.boot_on)
		config.ena_gpio_flags |= GPIOF_OUT_INIT_HIGH;

	max8952->rdev = regulator_register(&regulator, &config);

	if (IS_ERR(max8952->rdev)) {
		ret = PTR_ERR(max8952->rdev);
		dev_err(max8952->dev, "regulator init failed (%d)\n", ret);
		return ret;
	}

	max8952->vid0 = pdata->default_mode & 0x1;
	max8952->vid1 = (pdata->default_mode >> 1) & 0x1;

	if (gpio_is_valid(pdata->gpio_vid0) &&
			gpio_is_valid(pdata->gpio_vid1)) {
		if (!gpio_request(pdata->gpio_vid0, "MAX8952 VID0"))
			gpio_direction_output(pdata->gpio_vid0,
					(pdata->default_mode) & 0x1);
		else
			err = 1;

		if (!gpio_request(pdata->gpio_vid1, "MAX8952 VID1"))
			gpio_direction_output(pdata->gpio_vid1,
				(pdata->default_mode >> 1) & 0x1);
		else {
			if (!err)
				gpio_free(pdata->gpio_vid0);
			err = 2;
		}

	} else
		err = 3;

	if (err) {
		dev_warn(max8952->dev, "VID0/1 gpio invalid: "
				"DVS not available.\n");
		max8952->vid0 = 0;
		max8952->vid1 = 0;
		/* Mark invalid */
		pdata->gpio_vid0 = -1;
		pdata->gpio_vid1 = -1;

		/* Disable Pulldown of EN only */
		max8952_write_reg(max8952, MAX8952_REG_CONTROL, 0x60);

		dev_err(max8952->dev, "DVS modes disabled because VID0 and VID1"
				" do not have proper controls.\n");
	} else {
		/*
		 * Disable Pulldown on EN, VID0, VID1 to reduce
		 * leakage current of MAX8952 assuming that MAX8952
		 * is turned on (EN==1). Note that without having VID0/1
		 * properly connected, turning pulldown off can be
		 * problematic. Thus, turn this off only when they are
		 * controllable by GPIO.
		 */
		max8952_write_reg(max8952, MAX8952_REG_CONTROL, 0x0);
	}

	max8952_write_reg(max8952, MAX8952_REG_MODE0,
			(max8952_read_reg(max8952,
					  MAX8952_REG_MODE0) & 0xC0) |
			(pdata->dvs_mode[0] & 0x3F));
	max8952_write_reg(max8952, MAX8952_REG_MODE1,
			(max8952_read_reg(max8952,
					  MAX8952_REG_MODE1) & 0xC0) |
			(pdata->dvs_mode[1] & 0x3F));
	max8952_write_reg(max8952, MAX8952_REG_MODE2,
			(max8952_read_reg(max8952,
					  MAX8952_REG_MODE2) & 0xC0) |
			(pdata->dvs_mode[2] & 0x3F));
	max8952_write_reg(max8952, MAX8952_REG_MODE3,
			(max8952_read_reg(max8952,
					  MAX8952_REG_MODE3) & 0xC0) |
			(pdata->dvs_mode[3] & 0x3F));

	max8952_write_reg(max8952, MAX8952_REG_SYNC,
			(max8952_read_reg(max8952, MAX8952_REG_SYNC) & 0x3F) |
			((pdata->sync_freq & 0x3) << 6));
	max8952_write_reg(max8952, MAX8952_REG_RAMP,
			(max8952_read_reg(max8952, MAX8952_REG_RAMP) & 0x1F) |
			((pdata->ramp_speed & 0x7) << 5));

	i2c_set_clientdata(client, max8952);

	return 0;
}

static int max8952_pmic_remove(struct i2c_client *client)
{
	struct max8952_data *max8952 = i2c_get_clientdata(client);
	struct max8952_platform_data *pdata = max8952->pdata;
	struct regulator_dev *rdev = max8952->rdev;

	regulator_unregister(rdev);

	gpio_free(pdata->gpio_vid0);
	gpio_free(pdata->gpio_vid1);
	return 0;
}

static const struct i2c_device_id max8952_ids[] = {
	{ "max8952", 0 },
	{ },
};
MODULE_DEVICE_TABLE(i2c, max8952_ids);

static struct i2c_driver max8952_pmic_driver = {
	.probe		= max8952_pmic_probe,
	.remove		= max8952_pmic_remove,
	.driver		= {
		.name	= "max8952",
		.of_match_table = of_match_ptr(max8952_dt_match),
	},
	.id_table	= max8952_ids,
};

static int __init max8952_pmic_init(void)
{
	return i2c_add_driver(&max8952_pmic_driver);
}
subsys_initcall(max8952_pmic_init);

static void __exit max8952_pmic_exit(void)
{
	i2c_del_driver(&max8952_pmic_driver);
}
module_exit(max8952_pmic_exit);

MODULE_DESCRIPTION("MAXIM 8952 voltage regulator driver");
MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
MODULE_LICENSE("GPL");
Commit	Line	Data
202f4f53 MH	1	/*
	2	* max8952.c - Voltage and current regulation for the Maxim 8952
	3	*
	4	* Copyright (C) 2010 Samsung Electronics
	5	* MyungJoo Ham <myungjoo.ham@samsung.com>
	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License as published by
	9	* the Free Software Foundation; either version 2 of the License, or
	10	* (at your option) any later version.
	11	*
	12	* This program is distributed in the hope that it will be useful,
	13	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	* GNU General Public License for more details.
	16	*
	17	* You should have received a copy of the GNU General Public License
	18	* along with this program; if not, write to the Free Software
	19	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	20	*/
	21
	22	#include <linux/module.h>
	23	#include <linux/init.h>
	24	#include <linux/i2c.h>
	25	#include <linux/err.h>
	26	#include <linux/platform_device.h>
	27	#include <linux/regulator/driver.h>
	28	#include <linux/regulator/max8952.h>
202f4f53 MH	29	#include <linux/gpio.h>
202f4f53 MH	30	#include <linux/io.h>
3ff4aa95 TF	31	#include <linux/of.h>
	32	#include <linux/of_gpio.h>
	33	#include <linux/regulator/of_regulator.h>
202f4f53 MH	34	#include <linux/slab.h>
	35
	36	/* Registers */
	37	enum {
	38	MAX8952_REG_MODE0,
	39	MAX8952_REG_MODE1,
	40	MAX8952_REG_MODE2,
	41	MAX8952_REG_MODE3,
	42	MAX8952_REG_CONTROL,
	43	MAX8952_REG_SYNC,
	44	MAX8952_REG_RAMP,
	45	MAX8952_REG_CHIP_ID1,
	46	MAX8952_REG_CHIP_ID2,
	47	};
	48
	49	struct max8952_data {
	50	struct i2c_client *client;
	51	struct device *dev;
202f4f53 MH	52	struct max8952_platform_data *pdata;
	53	struct regulator_dev *rdev;
	54
	55	bool vid0;
	56	bool vid1;
202f4f53 MH	57	};
	58
	59	static int max8952_read_reg(struct max8952_data *max8952, u8 reg)
	60	{
	61	int ret = i2c_smbus_read_byte_data(max8952->client, reg);
	62	if (ret > 0)
	63	ret &= 0xff;
	64
	65	return ret;
	66	}
	67
	68	static int max8952_write_reg(struct max8952_data *max8952,
	69	u8 reg, u8 value)
	70	{
	71	return i2c_smbus_write_byte_data(max8952->client, reg, value);
	72	}
	73
202f4f53 MH	74	static int max8952_list_voltage(struct regulator_dev *rdev,
	75	unsigned int selector)
	76	{
	77	struct max8952_data *max8952 = rdev_get_drvdata(rdev);
	78
	79	if (rdev_get_id(rdev) != 0)
	80	return -EINVAL;
	81
b9b49af5	82	return (max8952->pdata->dvs_mode[selector] * 10 + 770) * 1000;
202f4f53 MH	83	}
202f4f53 MH	84
b9b49af5	85	static int max8952_get_voltage_sel(struct regulator_dev *rdev)
202f4f53 MH	86	{
	87	struct max8952_data *max8952 = rdev_get_drvdata(rdev);
	88	u8 vid = 0;
	89
	90	if (max8952->vid0)
	91	vid += 1;
	92	if (max8952->vid1)
	93	vid += 2;
	94
b9b49af5	95	return vid;
202f4f53 MH	96	}
202f4f53 MH	97
6ea67d04 AL	98	static int max8952_set_voltage_sel(struct regulator_dev *rdev,
6ea67d04 AL	99	unsigned selector)
202f4f53 MH	100	{
202f4f53 MH	101	struct max8952_data *max8952 = rdev_get_drvdata(rdev);
202f4f53 MH	102
202f4f53 MH	103	if (!gpio_is_valid(max8952->pdata->gpio_vid0) \|\|
e2cf3137	104	!gpio_is_valid(max8952->pdata->gpio_vid1)) {
202f4f53 MH	105	/* DVS not supported */
	106	return -EPERM;
	107	}
	108
6ea67d04 AL	109	max8952->vid0 = selector & 0x1;
	110	max8952->vid1 = (selector >> 1) & 0x1;
	111	gpio_set_value(max8952->pdata->gpio_vid0, max8952->vid0);
	112	gpio_set_value(max8952->pdata->gpio_vid1, max8952->vid1);
202f4f53 MH	113
	114	return 0;
	115	}
	116
	117	static struct regulator_ops max8952_ops = {
	118	.list_voltage = max8952_list_voltage,
b9b49af5	119	.get_voltage_sel = max8952_get_voltage_sel,
6ea67d04	120	.set_voltage_sel = max8952_set_voltage_sel,
202f4f53 MH	121	};
202f4f53 MH	122
bd6ff0d6	123	static const struct regulator_desc regulator = {
202f4f53 MH	124	.name = "MAX8952_VOUT",
	125	.id = 0,
	126	.n_voltages = MAX8952_NUM_DVS_MODE,
	127	.ops = &max8952_ops,
	128	.type = REGULATOR_VOLTAGE,
	129	.owner = THIS_MODULE,
	130	};
	131
3ff4aa95 TF	132	#ifdef CONFIG_OF
	133	static struct of_device_id max8952_dt_match[] = {
	134	{ .compatible = "maxim,max8952" },
	135	{},
	136	};
	137	MODULE_DEVICE_TABLE(of, max8952_dt_match);
	138
	139	static struct max8952_platform_data max8952_parse_dt(struct device dev)
	140	{
	141	struct max8952_platform_data *pd;
	142	struct device_node *np = dev->of_node;
	143	int ret;
	144	int i;
	145
	146	pd = devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
	147	if (!pd) {
	148	dev_err(dev, "Failed to allocate platform data\n");
	149	return NULL;
	150	}
	151
	152	pd->gpio_vid0 = of_get_named_gpio(np, "max8952,vid-gpios", 0);
	153	pd->gpio_vid1 = of_get_named_gpio(np, "max8952,vid-gpios", 1);
	154	pd->gpio_en = of_get_named_gpio(np, "max8952,en-gpio", 0);
	155
	156	if (of_property_read_u32(np, "max8952,default-mode", &pd->default_mode))
	157	dev_warn(dev, "Default mode not specified, assuming 0\n");
	158
	159	ret = of_property_read_u32_array(np, "max8952,dvs-mode-microvolt",
	160	pd->dvs_mode, ARRAY_SIZE(pd->dvs_mode));
	161	if (ret) {
	162	dev_err(dev, "max8952,dvs-mode-microvolt property not specified");
	163	return NULL;
	164	}
	165
	166	for (i = 0; i < ARRAY_SIZE(pd->dvs_mode); ++i) {
	167	if (pd->dvs_mode[i] < 770000 \|\| pd->dvs_mode[i] > 1400000) {
	168	dev_err(dev, "DVS voltage %d out of range\n", i);
	169	return NULL;
	170	}
	171	pd->dvs_mode[i] = (pd->dvs_mode[i] - 770000) / 10000;
	172	}
	173
	174	if (of_property_read_u32(np, "max8952,sync-freq", &pd->sync_freq))
	175	dev_warn(dev, "max8952,sync-freq property not specified, defaulting to 26MHz\n");
	176
	177	if (of_property_read_u32(np, "max8952,ramp-speed", &pd->ramp_speed))
	178	dev_warn(dev, "max8952,ramp-speed property not specified, defaulting to 32mV/us\n");
	179
	180	pd->reg_data = of_get_regulator_init_data(dev, np);
	181	if (!pd->reg_data) {
	182	dev_err(dev, "Failed to parse regulator init data\n");
	183	return NULL;
	184	}
	185
	186	return pd;
	187	}
	188	#else
	189	static struct max8952_platform_data max8952_parse_dt(struct device dev)
	190	{
	191	return NULL;
	192	}
	193	#endif
	194
a5023574	195	static int max8952_pmic_probe(struct i2c_client *client,
202f4f53 MH	196	const struct i2c_device_id *i2c_id)
	197	{
	198	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
	199	struct max8952_platform_data *pdata = client->dev.platform_data;
c172708d	200	struct regulator_config config = { };
202f4f53 MH	201	struct max8952_data *max8952;
	202
	203	int ret = 0, err = 0;
	204
3ff4aa95 TF	205	if (client->dev.of_node)
	206	pdata = max8952_parse_dt(&client->dev);
	207
202f4f53 MH	208	if (!pdata) {
	209	dev_err(&client->dev, "Require the platform data\n");
	210	return -EINVAL;
	211	}
	212
	213	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE))
	214	return -EIO;
	215
372de4aa AL	216	max8952 = devm_kzalloc(&client->dev, sizeof(struct max8952_data),
372de4aa AL	217	GFP_KERNEL);
202f4f53 MH	218	if (!max8952)
	219	return -ENOMEM;
	220
	221	max8952->client = client;
	222	max8952->dev = &client->dev;
	223	max8952->pdata = pdata;
202f4f53	224
c172708d	225	config.dev = max8952->dev;
3ec6eb9c	226	config.init_data = pdata->reg_data;
c172708d MB	227	config.driver_data = max8952;
c172708d MB	228
b669e0ad	229	config.ena_gpio = pdata->gpio_en;
3ec6eb9c	230	if (pdata->reg_data->constraints.boot_on)
b669e0ad AL	231	config.ena_gpio_flags \|= GPIOF_OUT_INIT_HIGH;
b669e0ad AL	232
c172708d	233	max8952->rdev = regulator_register(&regulator, &config);
202f4f53	234
da05738e AL	235	if (IS_ERR(max8952->rdev)) {
da05738e AL	236	ret = PTR_ERR(max8952->rdev);
202f4f53	237	dev_err(max8952->dev, "regulator init failed (%d)\n", ret);
372de4aa	238	return ret;
da05738e	239	}
202f4f53	240
c8237f01 AL	241	max8952->vid0 = pdata->default_mode & 0x1;
c8237f01 AL	242	max8952->vid1 = (pdata->default_mode >> 1) & 0x1;
202f4f53	243
202f4f53 MH	244	if (gpio_is_valid(pdata->gpio_vid0) &&
	245	gpio_is_valid(pdata->gpio_vid1)) {
	246	if (!gpio_request(pdata->gpio_vid0, "MAX8952 VID0"))
	247	gpio_direction_output(pdata->gpio_vid0,
c8237f01	248	(pdata->default_mode) & 0x1);
202f4f53 MH	249	else
	250	err = 1;
	251
	252	if (!gpio_request(pdata->gpio_vid1, "MAX8952 VID1"))
	253	gpio_direction_output(pdata->gpio_vid1,
c8237f01	254	(pdata->default_mode >> 1) & 0x1);
202f4f53 MH	255	else {
	256	if (!err)
	257	gpio_free(pdata->gpio_vid0);
	258	err = 2;
	259	}
	260
	261	} else
	262	err = 3;
	263
	264	if (err) {
	265	dev_warn(max8952->dev, "VID0/1 gpio invalid: "
25985edc	266	"DVS not available.\n");
202f4f53 MH	267	max8952->vid0 = 0;
	268	max8952->vid1 = 0;
	269	/* Mark invalid */
	270	pdata->gpio_vid0 = -1;
	271	pdata->gpio_vid1 = -1;
	272
	273	/* Disable Pulldown of EN only */
	274	max8952_write_reg(max8952, MAX8952_REG_CONTROL, 0x60);
	275
	276	dev_err(max8952->dev, "DVS modes disabled because VID0 and VID1"
	277	" do not have proper controls.\n");
	278	} else {
	279	/*
	280	* Disable Pulldown on EN, VID0, VID1 to reduce
	281	* leakage current of MAX8952 assuming that MAX8952
	282	* is turned on (EN==1). Note that without having VID0/1
	283	* properly connected, turning pulldown off can be
	284	* problematic. Thus, turn this off only when they are
	285	* controllable by GPIO.
	286	*/
	287	max8952_write_reg(max8952, MAX8952_REG_CONTROL, 0x0);
	288	}
	289
	290	max8952_write_reg(max8952, MAX8952_REG_MODE0,
	291	(max8952_read_reg(max8952,
	292	MAX8952_REG_MODE0) & 0xC0) \|
	293	(pdata->dvs_mode[0] & 0x3F));
	294	max8952_write_reg(max8952, MAX8952_REG_MODE1,
	295	(max8952_read_reg(max8952,
	296	MAX8952_REG_MODE1) & 0xC0) \|
	297	(pdata->dvs_mode[1] & 0x3F));
	298	max8952_write_reg(max8952, MAX8952_REG_MODE2,
	299	(max8952_read_reg(max8952,
	300	MAX8952_REG_MODE2) & 0xC0) \|
	301	(pdata->dvs_mode[2] & 0x3F));
	302	max8952_write_reg(max8952, MAX8952_REG_MODE3,
	303	(max8952_read_reg(max8952,
	304	MAX8952_REG_MODE3) & 0xC0) \|
	305	(pdata->dvs_mode[3] & 0x3F));
	306
	307	max8952_write_reg(max8952, MAX8952_REG_SYNC,
	308	(max8952_read_reg(max8952, MAX8952_REG_SYNC) & 0x3F) \|
	309	((pdata->sync_freq & 0x3) << 6));
	310	max8952_write_reg(max8952, MAX8952_REG_RAMP,
	311	(max8952_read_reg(max8952, MAX8952_REG_RAMP) & 0x1F) \|
	312	((pdata->ramp_speed & 0x7) << 5));
	313
	314	i2c_set_clientdata(client, max8952);
	315
da05738e	316	return 0;
202f4f53 MH	317	}
202f4f53 MH	318
8dc995f5	319	static int max8952_pmic_remove(struct i2c_client *client)
202f4f53 MH	320	{
	321	struct max8952_data *max8952 = i2c_get_clientdata(client);
	322	struct max8952_platform_data *pdata = max8952->pdata;
	323	struct regulator_dev *rdev = max8952->rdev;
	324
	325	regulator_unregister(rdev);
	326
	327	gpio_free(pdata->gpio_vid0);
	328	gpio_free(pdata->gpio_vid1);
202f4f53 MH	329	return 0;
	330	}
	331
	332	static const struct i2c_device_id max8952_ids[] = {
	333	{ "max8952", 0 },
	334	{ },
	335	};
	336	MODULE_DEVICE_TABLE(i2c, max8952_ids);
	337
	338	static struct i2c_driver max8952_pmic_driver = {
	339	.probe = max8952_pmic_probe,
5eb9f2b9	340	.remove = max8952_pmic_remove,
202f4f53 MH	341	.driver = {
202f4f53 MH	342	.name = "max8952",
3ff4aa95	343	.of_match_table = of_match_ptr(max8952_dt_match),
202f4f53 MH	344	},
	345	.id_table = max8952_ids,
	346	};
	347
	348	static int __init max8952_pmic_init(void)
	349	{
	350	return i2c_add_driver(&max8952_pmic_driver);
	351	}
	352	subsys_initcall(max8952_pmic_init);
	353
	354	static void __exit max8952_pmic_exit(void)
	355	{
	356	i2c_del_driver(&max8952_pmic_driver);
	357	}
	358	module_exit(max8952_pmic_exit);
	359
	360	MODULE_DESCRIPTION("MAXIM 8952 voltage regulator driver");
	361	MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
	362	MODULE_LICENSE("GPL");