[net-next-2.6.git] / drivers / regulator / lp3972.c

/*
 * Regulator driver for National Semiconductors LP3972 PMIC chip
 *
 * Based on lp3971.c
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 */

#include <linux/bug.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/kernel.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/lp3972.h>
#include <linux/slab.h>

struct lp3972 {
	struct device *dev;
	struct mutex io_lock;
	struct i2c_client *i2c;
	int num_regulators;
	struct regulator_dev **rdev;
};

/* LP3972 Control Registers */
#define LP3972_SCR_REG		0x07
#define LP3972_OVER1_REG	0x10
#define LP3972_OVSR1_REG	0x11
#define LP3972_OVER2_REG	0x12
#define LP3972_OVSR2_REG	0x13
#define LP3972_VCC1_REG		0x20
#define LP3972_ADTV1_REG	0x23
#define LP3972_ADTV2_REG	0x24
#define LP3972_AVRC_REG		0x25
#define LP3972_CDTC1_REG	0x26
#define LP3972_CDTC2_REG	0x27
#define LP3972_SDTV1_REG	0x29
#define LP3972_SDTV2_REG	0x2A
#define LP3972_MDTV1_REG	0x32
#define LP3972_MDTV2_REG	0x33
#define LP3972_L2VCR_REG	0x39
#define LP3972_L34VCR_REG	0x3A
#define LP3972_SCR1_REG		0x80
#define LP3972_SCR2_REG		0x81
#define LP3972_OEN3_REG		0x82
#define LP3972_OSR3_REG		0x83
#define LP3972_LOER4_REG	0x84
#define LP3972_B2TV_REG		0x85
#define LP3972_B3TV_REG		0x86
#define LP3972_B32RC_REG	0x87
#define LP3972_ISRA_REG		0x88
#define LP3972_BCCR_REG		0x89
#define LP3972_II1RR_REG	0x8E
#define LP3972_II2RR_REG	0x8F

#define LP3972_SYS_CONTROL1_REG		LP3972_SCR1_REG
/* System control register 1 initial value,
 * bits 5, 6 and 7 are EPROM programmable */
#define SYS_CONTROL1_INIT_VAL		0x02
#define SYS_CONTROL1_INIT_MASK		0x1F

#define LP3972_VOL_CHANGE_REG		LP3972_VCC1_REG
#define LP3972_VOL_CHANGE_FLAG_GO	0x01
#define LP3972_VOL_CHANGE_FLAG_MASK	0x03

/* LDO output enable mask */
#define LP3972_OEN3_L1EN	BIT(0)
#define LP3972_OVER2_LDO2_EN	BIT(2)
#define LP3972_OVER2_LDO3_EN	BIT(3)
#define LP3972_OVER2_LDO4_EN	BIT(4)
#define LP3972_OVER1_S_EN	BIT(2)

static const int ldo1_voltage_map[] = {
	1700, 1725, 1750, 1775, 1800, 1825, 1850, 1875,
	1900, 1925, 1950, 1975, 2000,
};

static const int ldo23_voltage_map[] = {
	1800, 1900, 2000, 2100, 2200, 2300, 2400, 2500,
	2600, 2700, 2800, 2900, 3000, 3100, 3200, 3300,
};

static const int ldo4_voltage_map[] = {
	1000, 1050, 1100, 1150, 1200, 1250, 1300, 1350,
	1400, 1500, 1800, 1900, 2500, 2800, 3000, 3300,
};

static const int ldo5_voltage_map[] = {
	   0,    0,    0,    0,    0,  850,  875,  900,
	 925,  950,  975, 1000, 1025, 1050, 1075, 1100,
	1125, 1150, 1175, 1200, 1225, 1250, 1275, 1300,
	1325, 1350, 1375, 1400, 1425, 1450, 1475, 1500,
};

static const int buck1_voltage_map[] = {
	 725,  750,  775,  800,  825,  850,  875,  900,
	 925,  950,  975, 1000, 1025, 1050, 1075, 1100,
	1125, 1150, 1175, 1200, 1225, 1250, 1275, 1300,
	1325, 1350, 1375, 1400, 1425, 1450, 1475, 1500,
};

static const int buck23_voltage_map[] = {
	   0,  800,  850,  900,  950, 1000, 1050, 1100,
	1150, 1200, 1250, 1300, 1350, 1400, 1450, 1500,
	1550, 1600, 1650, 1700, 1800, 1900, 2500, 2800,
	3000, 3300,
};

static const int *ldo_voltage_map[] = {
	ldo1_voltage_map,
	ldo23_voltage_map,
	ldo23_voltage_map,
	ldo4_voltage_map,
	ldo5_voltage_map,
};

static const int *buck_voltage_map[] = {
	buck1_voltage_map,
	buck23_voltage_map,
	buck23_voltage_map,
};

static const int ldo_output_enable_mask[] = {
	LP3972_OEN3_L1EN,
	LP3972_OVER2_LDO2_EN,
	LP3972_OVER2_LDO3_EN,
	LP3972_OVER2_LDO4_EN,
	LP3972_OVER1_S_EN,
};

static const int ldo_output_enable_addr[] = {
	LP3972_OEN3_REG,
	LP3972_OVER2_REG,
	LP3972_OVER2_REG,
	LP3972_OVER2_REG,
	LP3972_OVER1_REG,
};

static const int ldo_vol_ctl_addr[] = {
	LP3972_MDTV1_REG,
	LP3972_L2VCR_REG,
	LP3972_L34VCR_REG,
	LP3972_L34VCR_REG,
	LP3972_SDTV1_REG,
};

static const int buck_vol_enable_addr[] = {
	LP3972_OVER1_REG,
	LP3972_OEN3_REG,
	LP3972_OEN3_REG,
};

static const int buck_base_addr[] = {
	LP3972_ADTV1_REG,
	LP3972_B2TV_REG,
	LP3972_B3TV_REG,
};

#define LP3972_LDO_VOL_VALUE_MAP(x) (ldo_voltage_map[x])
#define LP3972_LDO_OUTPUT_ENABLE_MASK(x) (ldo_output_enable_mask[x])
#define LP3972_LDO_OUTPUT_ENABLE_REG(x) (ldo_output_enable_addr[x])

/*	LDO voltage control registers shift:
	LP3972_LDO1 -> 0, LP3972_LDO2 -> 4
	LP3972_LDO3 -> 0, LP3972_LDO4 -> 4
	LP3972_LDO5 -> 0
*/
#define LP3972_LDO_VOL_CONTR_SHIFT(x) (((x) & 1) << 2)
#define LP3972_LDO_VOL_CONTR_REG(x) (ldo_vol_ctl_addr[x])
#define LP3972_LDO_VOL_CHANGE_SHIFT(x) ((x) ? 4 : 6)

#define LP3972_LDO_VOL_MASK(x) (((x) % 4) ? 0x0f : 0x1f)
#define LP3972_LDO_VOL_MIN_IDX(x) (((x) == 4) ? 0x05 : 0x00)
#define LP3972_LDO_VOL_MAX_IDX(x) ((x) ? (((x) == 4) ? 0x1f : 0x0f) : 0x0c)

#define LP3972_BUCK_VOL_VALUE_MAP(x) (buck_voltage_map[x])
#define LP3972_BUCK_VOL_ENABLE_REG(x) (buck_vol_enable_addr[x])
#define LP3972_BUCK_VOL1_REG(x) (buck_base_addr[x])
#define LP3972_BUCK_VOL_MASK 0x1f
#define LP3972_BUCK_VOL_MIN_IDX(x) ((x) ? 0x01 : 0x00)
#define LP3972_BUCK_VOL_MAX_IDX(x) ((x) ? 0x19 : 0x1f)

static int lp3972_i2c_read(struct i2c_client *i2c, char reg, int count,
	u16 *dest)
{
	int ret;

	if (count != 1)
		return -EIO;
	ret = i2c_smbus_read_byte_data(i2c, reg);
	if (ret < 0)
		return ret;

	*dest = ret;
	return 0;
}

static int lp3972_i2c_write(struct i2c_client *i2c, char reg, int count,
	const u16 *src)
{
	if (count != 1)
		return -EIO;
	return i2c_smbus_write_byte_data(i2c, reg, *src);
}

static u8 lp3972_reg_read(struct lp3972 *lp3972, u8 reg)
{
	u16 val = 0;

	mutex_lock(&lp3972->io_lock);

	lp3972_i2c_read(lp3972->i2c, reg, 1, &val);

	dev_dbg(lp3972->dev, "reg read 0x%02x -> 0x%02x\n", (int)reg,
		(unsigned)val & 0xff);

	mutex_unlock(&lp3972->io_lock);

	return val & 0xff;
}

static int lp3972_set_bits(struct lp3972 *lp3972, u8 reg, u16 mask, u16 val)
{
	u16 tmp;
	int ret;

	mutex_lock(&lp3972->io_lock);

	ret = lp3972_i2c_read(lp3972->i2c, reg, 1, &tmp);
	tmp = (tmp & ~mask) | val;
	if (ret == 0) {
		ret = lp3972_i2c_write(lp3972->i2c, reg, 1, &tmp);
		dev_dbg(lp3972->dev, "reg write 0x%02x -> 0x%02x\n", (int)reg,
			(unsigned)val & 0xff);
	}
	mutex_unlock(&lp3972->io_lock);

	return ret;
}

static int lp3972_ldo_list_voltage(struct regulator_dev *dev, unsigned index)
{
	int ldo = rdev_get_id(dev) - LP3972_LDO1;
	return 1000 * LP3972_LDO_VOL_VALUE_MAP(ldo)[index];
}

static int lp3972_ldo_is_enabled(struct regulator_dev *dev)
{
	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
	int ldo = rdev_get_id(dev) - LP3972_LDO1;
	u16 mask = LP3972_LDO_OUTPUT_ENABLE_MASK(ldo);
	u16 val;

	val = lp3972_reg_read(lp3972, LP3972_LDO_OUTPUT_ENABLE_REG(ldo));
	return !!(val & mask);
}

static int lp3972_ldo_enable(struct regulator_dev *dev)
{
	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
	int ldo = rdev_get_id(dev) - LP3972_LDO1;
	u16 mask = LP3972_LDO_OUTPUT_ENABLE_MASK(ldo);

	return lp3972_set_bits(lp3972, LP3972_LDO_OUTPUT_ENABLE_REG(ldo),
				mask, mask);
}

static int lp3972_ldo_disable(struct regulator_dev *dev)
{
	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
	int ldo = rdev_get_id(dev) - LP3972_LDO1;
	u16 mask = LP3972_LDO_OUTPUT_ENABLE_MASK(ldo);

	return lp3972_set_bits(lp3972, LP3972_LDO_OUTPUT_ENABLE_REG(ldo),
				mask, 0);
}

static int lp3972_ldo_get_voltage(struct regulator_dev *dev)
{
	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
	int ldo = rdev_get_id(dev) - LP3972_LDO1;
	u16 mask = LP3972_LDO_VOL_MASK(ldo);
	u16 val, reg;

	reg = lp3972_reg_read(lp3972, LP3972_LDO_VOL_CONTR_REG(ldo));
	val = (reg >> LP3972_LDO_VOL_CONTR_SHIFT(ldo)) & mask;

	return 1000 * LP3972_LDO_VOL_VALUE_MAP(ldo)[val];
}

static int lp3972_ldo_set_voltage(struct regulator_dev *dev,
				  int min_uV, int max_uV)
{
	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
	int ldo = rdev_get_id(dev) - LP3972_LDO1;
	int min_vol = min_uV / 1000, max_vol = max_uV / 1000;
	const int *vol_map = LP3972_LDO_VOL_VALUE_MAP(ldo);
	u16 val;
	int shift, ret;

	if (min_vol < vol_map[LP3972_LDO_VOL_MIN_IDX(ldo)] ||
	    min_vol > vol_map[LP3972_LDO_VOL_MAX_IDX(ldo)])
		return -EINVAL;

	for (val = LP3972_LDO_VOL_MIN_IDX(ldo);
		val <= LP3972_LDO_VOL_MAX_IDX(ldo); val++)
		if (vol_map[val] >= min_vol)
			break;

	if (val > LP3972_LDO_VOL_MAX_IDX(ldo) || vol_map[val] > max_vol)
		return -EINVAL;

	shift = LP3972_LDO_VOL_CONTR_SHIFT(ldo);
	ret = lp3972_set_bits(lp3972, LP3972_LDO_VOL_CONTR_REG(ldo),
		LP3972_LDO_VOL_MASK(ldo) << shift, val << shift);

	if (ret)
		return ret;

	/*
	 * LDO1 and LDO5 support voltage control by either target voltage1
	 * or target voltage2 register.
	 * We use target voltage1 register for LDO1 and LDO5 in this driver.
	 * We need to update voltage change control register(0x20) to enable
	 * LDO1 and LDO5 to change to their programmed target values.
	 */
	switch (ldo) {
	case LP3972_LDO1:
	case LP3972_LDO5:
		shift = LP3972_LDO_VOL_CHANGE_SHIFT(ldo);
		ret = lp3972_set_bits(lp3972, LP3972_VOL_CHANGE_REG,
			LP3972_VOL_CHANGE_FLAG_MASK << shift,
			LP3972_VOL_CHANGE_FLAG_GO << shift);
		if (ret)
			return ret;

		ret = lp3972_set_bits(lp3972, LP3972_VOL_CHANGE_REG,
			LP3972_VOL_CHANGE_FLAG_MASK << shift, 0);
		break;
	}

	return ret;
}

static struct regulator_ops lp3972_ldo_ops = {
	.list_voltage = lp3972_ldo_list_voltage,
	.is_enabled = lp3972_ldo_is_enabled,
	.enable = lp3972_ldo_enable,
	.disable = lp3972_ldo_disable,
	.get_voltage = lp3972_ldo_get_voltage,
	.set_voltage = lp3972_ldo_set_voltage,
};

static int lp3972_dcdc_list_voltage(struct regulator_dev *dev, unsigned index)
{
	int buck = rdev_get_id(dev) - LP3972_DCDC1;
	return 1000 * buck_voltage_map[buck][index];
}

static int lp3972_dcdc_is_enabled(struct regulator_dev *dev)
{
	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
	int buck = rdev_get_id(dev) - LP3972_DCDC1;
	u16 mask = 1 << (buck * 2);
	u16 val;

	val = lp3972_reg_read(lp3972, LP3972_BUCK_VOL_ENABLE_REG(buck));
	return !!(val & mask);
}

static int lp3972_dcdc_enable(struct regulator_dev *dev)
{
	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
	int buck = rdev_get_id(dev) - LP3972_DCDC1;
	u16 mask = 1 << (buck * 2);
	u16 val;

	val = lp3972_set_bits(lp3972, LP3972_BUCK_VOL_ENABLE_REG(buck),
				mask, mask);
	return val;
}

static int lp3972_dcdc_disable(struct regulator_dev *dev)
{
	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
	int buck = rdev_get_id(dev) - LP3972_DCDC1;
	u16 mask = 1 << (buck * 2);
	u16 val;

	val = lp3972_set_bits(lp3972, LP3972_BUCK_VOL_ENABLE_REG(buck),
				mask, 0);
	return val;
}

static int lp3972_dcdc_get_voltage(struct regulator_dev *dev)
{
	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
	int buck = rdev_get_id(dev) - LP3972_DCDC1;
	u16 reg;
	int val;

	reg = lp3972_reg_read(lp3972, LP3972_BUCK_VOL1_REG(buck));
	reg &= LP3972_BUCK_VOL_MASK;
	if (reg <= LP3972_BUCK_VOL_MAX_IDX(buck))
		val = 1000 * buck_voltage_map[buck][reg];
	else {
		val = 0;
		dev_warn(&dev->dev, "chip reported incorrect voltage value."
				    " reg = %d\n", reg);
	}

	return val;
}

static int lp3972_dcdc_set_voltage(struct regulator_dev *dev,
				  int min_uV, int max_uV)
{
	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
	int buck = rdev_get_id(dev) - LP3972_DCDC1;
	int min_vol = min_uV / 1000, max_vol = max_uV / 1000;
	const int *vol_map = buck_voltage_map[buck];
	u16 val;
	int ret;

	if (min_vol < vol_map[LP3972_BUCK_VOL_MIN_IDX(buck)] ||
	    min_vol > vol_map[LP3972_BUCK_VOL_MAX_IDX(buck)])
		return -EINVAL;

	for (val = LP3972_BUCK_VOL_MIN_IDX(buck);
		val <= LP3972_BUCK_VOL_MAX_IDX(buck); val++)
		if (vol_map[val] >= min_vol)
			break;

	if (val > LP3972_BUCK_VOL_MAX_IDX(buck) ||
	    vol_map[val] > max_vol)
		return -EINVAL;

	ret = lp3972_set_bits(lp3972, LP3972_BUCK_VOL1_REG(buck),
				LP3972_BUCK_VOL_MASK, val);
	if (ret)
		return ret;

	if (buck != 0)
		return ret;

	ret = lp3972_set_bits(lp3972, LP3972_VOL_CHANGE_REG,
		LP3972_VOL_CHANGE_FLAG_MASK, LP3972_VOL_CHANGE_FLAG_GO);
	if (ret)
		return ret;

	return lp3972_set_bits(lp3972, LP3972_VOL_CHANGE_REG,
				LP3972_VOL_CHANGE_FLAG_MASK, 0);
}

static struct regulator_ops lp3972_dcdc_ops = {
	.list_voltage = lp3972_dcdc_list_voltage,
	.is_enabled = lp3972_dcdc_is_enabled,
	.enable = lp3972_dcdc_enable,
	.disable = lp3972_dcdc_disable,
	.get_voltage = lp3972_dcdc_get_voltage,
	.set_voltage = lp3972_dcdc_set_voltage,
};

static struct regulator_desc regulators[] = {
	{
		.name = "LDO1",
		.id = LP3972_LDO1,
		.ops = &lp3972_ldo_ops,
		.n_voltages = ARRAY_SIZE(ldo1_voltage_map),
		.type = REGULATOR_VOLTAGE,
		.owner = THIS_MODULE,
	},
	{
		.name = "LDO2",
		.id = LP3972_LDO2,
		.ops = &lp3972_ldo_ops,
		.n_voltages = ARRAY_SIZE(ldo23_voltage_map),
		.type = REGULATOR_VOLTAGE,
		.owner = THIS_MODULE,
	},
	{
		.name = "LDO3",
		.id = LP3972_LDO3,
		.ops = &lp3972_ldo_ops,
		.n_voltages = ARRAY_SIZE(ldo23_voltage_map),
		.type = REGULATOR_VOLTAGE,
		.owner = THIS_MODULE,
	},
	{
		.name = "LDO4",
		.id = LP3972_LDO4,
		.ops = &lp3972_ldo_ops,
		.n_voltages = ARRAY_SIZE(ldo4_voltage_map),
		.type = REGULATOR_VOLTAGE,
		.owner = THIS_MODULE,
	},
	{
		.name = "LDO5",
		.id = LP3972_LDO5,
		.ops = &lp3972_ldo_ops,
		.n_voltages = ARRAY_SIZE(ldo5_voltage_map),
		.type = REGULATOR_VOLTAGE,
		.owner = THIS_MODULE,
	},
	{
		.name = "DCDC1",
		.id = LP3972_DCDC1,
		.ops = &lp3972_dcdc_ops,
		.n_voltages = ARRAY_SIZE(buck1_voltage_map),
		.type = REGULATOR_VOLTAGE,
		.owner = THIS_MODULE,
	},
	{
		.name = "DCDC2",
		.id = LP3972_DCDC2,
		.ops = &lp3972_dcdc_ops,
		.n_voltages = ARRAY_SIZE(buck23_voltage_map),
		.type = REGULATOR_VOLTAGE,
		.owner = THIS_MODULE,
	},
	{
		.name = "DCDC3",
		.id = LP3972_DCDC3,
		.ops = &lp3972_dcdc_ops,
		.n_voltages = ARRAY_SIZE(buck23_voltage_map),
		.type = REGULATOR_VOLTAGE,
		.owner = THIS_MODULE,
	},
};

static int __devinit setup_regulators(struct lp3972 *lp3972,
	struct lp3972_platform_data *pdata)
{
	int i, err;

	lp3972->num_regulators = pdata->num_regulators;
	lp3972->rdev = kcalloc(pdata->num_regulators,
				sizeof(struct regulator_dev *), GFP_KERNEL);
	if (!lp3972->rdev) {
		err = -ENOMEM;
		goto err_nomem;
	}

	/* Instantiate the regulators */
	for (i = 0; i < pdata->num_regulators; i++) {
		struct lp3972_regulator_subdev *reg = &pdata->regulators[i];
		lp3972->rdev[i] = regulator_register(&regulators[reg->id],
					lp3972->dev, reg->initdata, lp3972);

		if (IS_ERR(lp3972->rdev[i])) {
			err = PTR_ERR(lp3972->rdev[i]);
			dev_err(lp3972->dev, "regulator init failed: %d\n",
				err);
			goto error;
		}
	}

	return 0;
error:
	while (--i >= 0)
		regulator_unregister(lp3972->rdev[i]);
	kfree(lp3972->rdev);
	lp3972->rdev = NULL;
err_nomem:
	return err;
}

static int __devinit lp3972_i2c_probe(struct i2c_client *i2c,
			    const struct i2c_device_id *id)
{
	struct lp3972 *lp3972;
	struct lp3972_platform_data *pdata = i2c->dev.platform_data;
	int ret;
	u16 val;

	if (!pdata) {
		dev_dbg(&i2c->dev, "No platform init data supplied\n");
		return -ENODEV;
	}

	lp3972 = kzalloc(sizeof(struct lp3972), GFP_KERNEL);
	if (!lp3972)
		return -ENOMEM;

	lp3972->i2c = i2c;
	lp3972->dev = &i2c->dev;

	mutex_init(&lp3972->io_lock);

	/* Detect LP3972 */
	ret = lp3972_i2c_read(i2c, LP3972_SYS_CONTROL1_REG, 1, &val);
	if (ret == 0 &&
		(val & SYS_CONTROL1_INIT_MASK) != SYS_CONTROL1_INIT_VAL) {
		ret = -ENODEV;
		dev_err(&i2c->dev, "chip reported: val = 0x%x\n", val);
	}
	if (ret < 0) {
		dev_err(&i2c->dev, "failed to detect device. ret = %d\n", ret);
		goto err_detect;
	}

	ret = setup_regulators(lp3972, pdata);
	if (ret < 0)
		goto err_detect;

	i2c_set_clientdata(i2c, lp3972);
	return 0;

err_detect:
	kfree(lp3972);
	return ret;
}

static int __devexit lp3972_i2c_remove(struct i2c_client *i2c)
{
	struct lp3972 *lp3972 = i2c_get_clientdata(i2c);
	int i;

	for (i = 0; i < lp3972->num_regulators; i++)
		regulator_unregister(lp3972->rdev[i]);
	kfree(lp3972->rdev);
	kfree(lp3972);

	return 0;
}

static const struct i2c_device_id lp3972_i2c_id[] = {
	{ "lp3972", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, lp3972_i2c_id);

static struct i2c_driver lp3972_i2c_driver = {
	.driver = {
		.name = "lp3972",
		.owner = THIS_MODULE,
	},
	.probe    = lp3972_i2c_probe,
	.remove   = __devexit_p(lp3972_i2c_remove),
	.id_table = lp3972_i2c_id,
};

static int __init lp3972_module_init(void)
{
	return i2c_add_driver(&lp3972_i2c_driver);
}
subsys_initcall(lp3972_module_init);

static void __exit lp3972_module_exit(void)
{
	i2c_del_driver(&lp3972_i2c_driver);
}
module_exit(lp3972_module_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Axel Lin <axel.lin@gmail.com>");
MODULE_DESCRIPTION("LP3972 PMIC driver");
Commit	Line	Data
5976f095 AL	1	/*
	2	* Regulator driver for National Semiconductors LP3972 PMIC chip
	3	*
	4	* Based on lp3971.c
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License version 2 as
	8	* published by the Free Software Foundation.
	9	*
	10	*/
	11
	12	#include <linux/bug.h>
	13	#include <linux/err.h>
	14	#include <linux/i2c.h>
	15	#include <linux/kernel.h>
	16	#include <linux/regulator/driver.h>
	17	#include <linux/regulator/lp3972.h>
	18	#include <linux/slab.h>
	19
	20	struct lp3972 {
	21	struct device *dev;
	22	struct mutex io_lock;
	23	struct i2c_client *i2c;
	24	int num_regulators;
	25	struct regulator_dev **rdev;
	26	};
	27
	28	/* LP3972 Control Registers */
	29	#define LP3972_SCR_REG 0x07
	30	#define LP3972_OVER1_REG 0x10
	31	#define LP3972_OVSR1_REG 0x11
	32	#define LP3972_OVER2_REG 0x12
	33	#define LP3972_OVSR2_REG 0x13
	34	#define LP3972_VCC1_REG 0x20
	35	#define LP3972_ADTV1_REG 0x23
	36	#define LP3972_ADTV2_REG 0x24
	37	#define LP3972_AVRC_REG 0x25
	38	#define LP3972_CDTC1_REG 0x26
	39	#define LP3972_CDTC2_REG 0x27
	40	#define LP3972_SDTV1_REG 0x29
	41	#define LP3972_SDTV2_REG 0x2A
	42	#define LP3972_MDTV1_REG 0x32
	43	#define LP3972_MDTV2_REG 0x33
	44	#define LP3972_L2VCR_REG 0x39
	45	#define LP3972_L34VCR_REG 0x3A
	46	#define LP3972_SCR1_REG 0x80
	47	#define LP3972_SCR2_REG 0x81
	48	#define LP3972_OEN3_REG 0x82
	49	#define LP3972_OSR3_REG 0x83
	50	#define LP3972_LOER4_REG 0x84
	51	#define LP3972_B2TV_REG 0x85
	52	#define LP3972_B3TV_REG 0x86
	53	#define LP3972_B32RC_REG 0x87
	54	#define LP3972_ISRA_REG 0x88
	55	#define LP3972_BCCR_REG 0x89
	56	#define LP3972_II1RR_REG 0x8E
	57	#define LP3972_II2RR_REG 0x8F
	58
	59	#define LP3972_SYS_CONTROL1_REG LP3972_SCR1_REG
	60	/* System control register 1 initial value,
	61	* bits 5, 6 and 7 are EPROM programmable */
	62	#define SYS_CONTROL1_INIT_VAL 0x02
	63	#define SYS_CONTROL1_INIT_MASK 0x1F
	64
65	#define LP3972_VOL_CHANGE_REG LP3972_VCC1_REG
66	#define LP3972_VOL_CHANGE_FLAG_GO 0x01
67	#define LP3972_VOL_CHANGE_FLAG_MASK 0x03
68
69	/* LDO output enable mask */
70	#define LP3972_OEN3_L1EN BIT(0)
71	#define LP3972_OVER2_LDO2_EN BIT(2)
72	#define LP3972_OVER2_LDO3_EN BIT(3)
73	#define LP3972_OVER2_LDO4_EN BIT(4)
74	#define LP3972_OVER1_S_EN BIT(2)
75
76	static const int ldo1_voltage_map[] = {
77	1700, 1725, 1750, 1775, 1800, 1825, 1850, 1875,
78	1900, 1925, 1950, 1975, 2000,
79	};
80
81	static const int ldo23_voltage_map[] = {
82	1800, 1900, 2000, 2100, 2200, 2300, 2400, 2500,
83	2600, 2700, 2800, 2900, 3000, 3100, 3200, 3300,
84	};
85
86	static const int ldo4_voltage_map[] = {
87	1000, 1050, 1100, 1150, 1200, 1250, 1300, 1350,
88	1400, 1500, 1800, 1900, 2500, 2800, 3000, 3300,
89	};
90
91	static const int ldo5_voltage_map[] = {
92	0, 0, 0, 0, 0, 850, 875, 900,
93	925, 950, 975, 1000, 1025, 1050, 1075, 1100,
94	1125, 1150, 1175, 1200, 1225, 1250, 1275, 1300,
95	1325, 1350, 1375, 1400, 1425, 1450, 1475, 1500,
96	};
97
98	static const int buck1_voltage_map[] = {
99	725, 750, 775, 800, 825, 850, 875, 900,
100	925, 950, 975, 1000, 1025, 1050, 1075, 1100,
101	1125, 1150, 1175, 1200, 1225, 1250, 1275, 1300,
102	1325, 1350, 1375, 1400, 1425, 1450, 1475, 1500,
103	};
104
105	static const int buck23_voltage_map[] = {
106	0, 800, 850, 900, 950, 1000, 1050, 1100,
107	1150, 1200, 1250, 1300, 1350, 1400, 1450, 1500,
108	1550, 1600, 1650, 1700, 1800, 1900, 2500, 2800,
109	3000, 3300,
110	};
111
112	static const int *ldo_voltage_map[] = {
113	ldo1_voltage_map,
114	ldo23_voltage_map,
115	ldo23_voltage_map,
116	ldo4_voltage_map,
117	ldo5_voltage_map,
118	};
119
120	static const int *buck_voltage_map[] = {
121	buck1_voltage_map,
122	buck23_voltage_map,
123	buck23_voltage_map,
124	};
125
126	static const int ldo_output_enable_mask[] = {
127	LP3972_OEN3_L1EN,
128	LP3972_OVER2_LDO2_EN,
129	LP3972_OVER2_LDO3_EN,
130	LP3972_OVER2_LDO4_EN,
131	LP3972_OVER1_S_EN,
132	};
133
134	static const int ldo_output_enable_addr[] = {
135	LP3972_OEN3_REG,
136	LP3972_OVER2_REG,
137	LP3972_OVER2_REG,
138	LP3972_OVER2_REG,
139	LP3972_OVER1_REG,
140	};
141
142	static const int ldo_vol_ctl_addr[] = {
143	LP3972_MDTV1_REG,
144	LP3972_L2VCR_REG,
145	LP3972_L34VCR_REG,
146	LP3972_L34VCR_REG,
147	LP3972_SDTV1_REG,
148	};
149
150	static const int buck_vol_enable_addr[] = {
151	LP3972_OVER1_REG,
152	LP3972_OEN3_REG,
153	LP3972_OEN3_REG,
154	};
155
156	static const int buck_base_addr[] = {
157	LP3972_ADTV1_REG,
158	LP3972_B2TV_REG,
159	LP3972_B3TV_REG,
160	};
161
162	#define LP3972_LDO_VOL_VALUE_MAP(x) (ldo_voltage_map[x])
163	#define LP3972_LDO_OUTPUT_ENABLE_MASK(x) (ldo_output_enable_mask[x])
164	#define LP3972_LDO_OUTPUT_ENABLE_REG(x) (ldo_output_enable_addr[x])
165
166	/* LDO voltage control registers shift:
167	LP3972_LDO1 -> 0, LP3972_LDO2 -> 4
168	LP3972_LDO3 -> 0, LP3972_LDO4 -> 4
169	LP3972_LDO5 -> 0
170	*/
171	#define LP3972_LDO_VOL_CONTR_SHIFT(x) (((x) & 1) << 2)
172	#define LP3972_LDO_VOL_CONTR_REG(x) (ldo_vol_ctl_addr[x])
173	#define LP3972_LDO_VOL_CHANGE_SHIFT(x) ((x) ? 4 : 6)
174
175	#define LP3972_LDO_VOL_MASK(x) (((x) % 4) ? 0x0f : 0x1f)
176	#define LP3972_LDO_VOL_MIN_IDX(x) (((x) == 4) ? 0x05 : 0x00)
177	#define LP3972_LDO_VOL_MAX_IDX(x) ((x) ? (((x) == 4) ? 0x1f : 0x0f) : 0x0c)
178
179	#define LP3972_BUCK_VOL_VALUE_MAP(x) (buck_voltage_map[x])
180	#define LP3972_BUCK_VOL_ENABLE_REG(x) (buck_vol_enable_addr[x])
181	#define LP3972_BUCK_VOL1_REG(x) (buck_base_addr[x])
182	#define LP3972_BUCK_VOL_MASK 0x1f
183	#define LP3972_BUCK_VOL_MIN_IDX(x) ((x) ? 0x01 : 0x00)
184	#define LP3972_BUCK_VOL_MAX_IDX(x) ((x) ? 0x19 : 0x1f)
185
186	static int lp3972_i2c_read(struct i2c_client *i2c, char reg, int count,
187	u16 *dest)
188	{
189	int ret;
190
191	if (count != 1)
192	return -EIO;
193	ret = i2c_smbus_read_byte_data(i2c, reg);
194	if (ret < 0)
993af7c0	195	return ret;
5976f095 AL	196
	197	*dest = ret;
	198	return 0;
	199	}
	200
	201	static int lp3972_i2c_write(struct i2c_client *i2c, char reg, int count,
	202	const u16 *src)
	203	{
	204	if (count != 1)
	205	return -EIO;
	206	return i2c_smbus_write_byte_data(i2c, reg, *src);
	207	}
	208
	209	static u8 lp3972_reg_read(struct lp3972 *lp3972, u8 reg)
	210	{
	211	u16 val = 0;
	212
	213	mutex_lock(&lp3972->io_lock);
	214
	215	lp3972_i2c_read(lp3972->i2c, reg, 1, &val);
	216
	217	dev_dbg(lp3972->dev, "reg read 0x%02x -> 0x%02x\n", (int)reg,
993af7c0	218	(unsigned)val & 0xff);
5976f095 AL	219
	220	mutex_unlock(&lp3972->io_lock);
	221
	222	return val & 0xff;
	223	}
	224
	225	static int lp3972_set_bits(struct lp3972 *lp3972, u8 reg, u16 mask, u16 val)
	226	{
	227	u16 tmp;
	228	int ret;
	229
	230	mutex_lock(&lp3972->io_lock);
	231
	232	ret = lp3972_i2c_read(lp3972->i2c, reg, 1, &tmp);
	233	tmp = (tmp & ~mask) \| val;
	234	if (ret == 0) {
	235	ret = lp3972_i2c_write(lp3972->i2c, reg, 1, &tmp);
	236	dev_dbg(lp3972->dev, "reg write 0x%02x -> 0x%02x\n", (int)reg,
993af7c0	237	(unsigned)val & 0xff);
5976f095 AL	238	}
	239	mutex_unlock(&lp3972->io_lock);
	240
	241	return ret;
	242	}
	243
	244	static int lp3972_ldo_list_voltage(struct regulator_dev *dev, unsigned index)
	245	{
	246	int ldo = rdev_get_id(dev) - LP3972_LDO1;
	247	return 1000 * LP3972_LDO_VOL_VALUE_MAP(ldo)[index];
	248	}
	249
	250	static int lp3972_ldo_is_enabled(struct regulator_dev *dev)
	251	{
	252	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
	253	int ldo = rdev_get_id(dev) - LP3972_LDO1;
	254	u16 mask = LP3972_LDO_OUTPUT_ENABLE_MASK(ldo);
	255	u16 val;
	256
	257	val = lp3972_reg_read(lp3972, LP3972_LDO_OUTPUT_ENABLE_REG(ldo));
	258	return !!(val & mask);
	259	}
	260
	261	static int lp3972_ldo_enable(struct regulator_dev *dev)
	262	{
	263	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
	264	int ldo = rdev_get_id(dev) - LP3972_LDO1;
	265	u16 mask = LP3972_LDO_OUTPUT_ENABLE_MASK(ldo);
	266
	267	return lp3972_set_bits(lp3972, LP3972_LDO_OUTPUT_ENABLE_REG(ldo),
	268	mask, mask);
	269	}
	270
	271	static int lp3972_ldo_disable(struct regulator_dev *dev)
	272	{
	273	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
	274	int ldo = rdev_get_id(dev) - LP3972_LDO1;
	275	u16 mask = LP3972_LDO_OUTPUT_ENABLE_MASK(ldo);
	276
	277	return lp3972_set_bits(lp3972, LP3972_LDO_OUTPUT_ENABLE_REG(ldo),
	278	mask, 0);
	279	}
	280
	281	static int lp3972_ldo_get_voltage(struct regulator_dev *dev)
	282	{
	283	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
	284	int ldo = rdev_get_id(dev) - LP3972_LDO1;
	285	u16 mask = LP3972_LDO_VOL_MASK(ldo);
	286	u16 val, reg;
	287
	288	reg = lp3972_reg_read(lp3972, LP3972_LDO_VOL_CONTR_REG(ldo));
	289	val = (reg >> LP3972_LDO_VOL_CONTR_SHIFT(ldo)) & mask;
	290
	291	return 1000 * LP3972_LDO_VOL_VALUE_MAP(ldo)[val];
	292	}
	293
	294	static int lp3972_ldo_set_voltage(struct regulator_dev *dev,
	295	int min_uV, int max_uV)
	296	{
	297	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
	298	int ldo = rdev_get_id(dev) - LP3972_LDO1;
	299	int min_vol = min_uV / 1000, max_vol = max_uV / 1000;
	300	const int *vol_map = LP3972_LDO_VOL_VALUE_MAP(ldo);
	301	u16 val;
302	int shift, ret;
303
304	if (min_vol < vol_map[LP3972_LDO_VOL_MIN_IDX(ldo)] \|\|
305	min_vol > vol_map[LP3972_LDO_VOL_MAX_IDX(ldo)])
306	return -EINVAL;
307
308	for (val = LP3972_LDO_VOL_MIN_IDX(ldo);
309	val <= LP3972_LDO_VOL_MAX_IDX(ldo); val++)
310	if (vol_map[val] >= min_vol)
311	break;
312
313	if (val > LP3972_LDO_VOL_MAX_IDX(ldo) \|\| vol_map[val] > max_vol)
314	return -EINVAL;
315
316	shift = LP3972_LDO_VOL_CONTR_SHIFT(ldo);
317	ret = lp3972_set_bits(lp3972, LP3972_LDO_VOL_CONTR_REG(ldo),
318	LP3972_LDO_VOL_MASK(ldo) << shift, val << shift);
319
320	if (ret)
321	return ret;
322
993af7c0 AL	323	/*
	324	* LDO1 and LDO5 support voltage control by either target voltage1
	325	* or target voltage2 register.
	326	* We use target voltage1 register for LDO1 and LDO5 in this driver.
	327	* We need to update voltage change control register(0x20) to enable
	328	* LDO1 and LDO5 to change to their programmed target values.
	329	*/
5976f095 AL	330	switch (ldo) {
	331	case LP3972_LDO1:
	332	case LP3972_LDO5:
	333	shift = LP3972_LDO_VOL_CHANGE_SHIFT(ldo);
	334	ret = lp3972_set_bits(lp3972, LP3972_VOL_CHANGE_REG,
	335	LP3972_VOL_CHANGE_FLAG_MASK << shift,
	336	LP3972_VOL_CHANGE_FLAG_GO << shift);
	337	if (ret)
	338	return ret;
	339
	340	ret = lp3972_set_bits(lp3972, LP3972_VOL_CHANGE_REG,
	341	LP3972_VOL_CHANGE_FLAG_MASK << shift, 0);
	342	break;
	343	}
	344
	345	return ret;
	346	}
	347
	348	static struct regulator_ops lp3972_ldo_ops = {
	349	.list_voltage = lp3972_ldo_list_voltage,
	350	.is_enabled = lp3972_ldo_is_enabled,
	351	.enable = lp3972_ldo_enable,
	352	.disable = lp3972_ldo_disable,
	353	.get_voltage = lp3972_ldo_get_voltage,
	354	.set_voltage = lp3972_ldo_set_voltage,
	355	};
	356
	357	static int lp3972_dcdc_list_voltage(struct regulator_dev *dev, unsigned index)
	358	{
	359	int buck = rdev_get_id(dev) - LP3972_DCDC1;
	360	return 1000 * buck_voltage_map[buck][index];
	361	}
	362
	363	static int lp3972_dcdc_is_enabled(struct regulator_dev *dev)
	364	{
	365	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
	366	int buck = rdev_get_id(dev) - LP3972_DCDC1;
	367	u16 mask = 1 << (buck * 2);
	368	u16 val;
	369
	370	val = lp3972_reg_read(lp3972, LP3972_BUCK_VOL_ENABLE_REG(buck));
	371	return !!(val & mask);
	372	}
	373
	374	static int lp3972_dcdc_enable(struct regulator_dev *dev)
	375	{
	376	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
	377	int buck = rdev_get_id(dev) - LP3972_DCDC1;
	378	u16 mask = 1 << (buck * 2);
	379	u16 val;
	380
	381	val = lp3972_set_bits(lp3972, LP3972_BUCK_VOL_ENABLE_REG(buck),
	382	mask, mask);
	383	return val;
	384	}
	385
	386	static int lp3972_dcdc_disable(struct regulator_dev *dev)
	387	{
	388	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
	389	int buck = rdev_get_id(dev) - LP3972_DCDC1;
	390	u16 mask = 1 << (buck * 2);
	391	u16 val;
	392
	393	val = lp3972_set_bits(lp3972, LP3972_BUCK_VOL_ENABLE_REG(buck),
394	mask, 0);
395	return val;
396	}
397
398	static int lp3972_dcdc_get_voltage(struct regulator_dev *dev)
399	{
400	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
401	int buck = rdev_get_id(dev) - LP3972_DCDC1;
402	u16 reg;
403	int val;
404
405	reg = lp3972_reg_read(lp3972, LP3972_BUCK_VOL1_REG(buck));
406	reg &= LP3972_BUCK_VOL_MASK;
407	if (reg <= LP3972_BUCK_VOL_MAX_IDX(buck))
408	val = 1000 * buck_voltage_map[buck][reg];
409	else {
410	val = 0;
993af7c0 AL	411	dev_warn(&dev->dev, "chip reported incorrect voltage value."
993af7c0 AL	412	" reg = %d\n", reg);
5976f095 AL	413	}
	414
	415	return val;
	416	}
	417
	418	static int lp3972_dcdc_set_voltage(struct regulator_dev *dev,
	419	int min_uV, int max_uV)
	420	{
	421	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
	422	int buck = rdev_get_id(dev) - LP3972_DCDC1;
	423	int min_vol = min_uV / 1000, max_vol = max_uV / 1000;
	424	const int *vol_map = buck_voltage_map[buck];
	425	u16 val;
	426	int ret;
	427
	428	if (min_vol < vol_map[LP3972_BUCK_VOL_MIN_IDX(buck)] \|\|
	429	min_vol > vol_map[LP3972_BUCK_VOL_MAX_IDX(buck)])
	430	return -EINVAL;
	431
	432	for (val = LP3972_BUCK_VOL_MIN_IDX(buck);
	433	val <= LP3972_BUCK_VOL_MAX_IDX(buck); val++)
	434	if (vol_map[val] >= min_vol)
	435	break;
	436
	437	if (val > LP3972_BUCK_VOL_MAX_IDX(buck) \|\|
	438	vol_map[val] > max_vol)
	439	return -EINVAL;
	440
	441	ret = lp3972_set_bits(lp3972, LP3972_BUCK_VOL1_REG(buck),
	442	LP3972_BUCK_VOL_MASK, val);
	443	if (ret)
	444	return ret;
	445
	446	if (buck != 0)
	447	return ret;
	448
	449	ret = lp3972_set_bits(lp3972, LP3972_VOL_CHANGE_REG,
	450	LP3972_VOL_CHANGE_FLAG_MASK, LP3972_VOL_CHANGE_FLAG_GO);
	451	if (ret)
	452	return ret;
	453
	454	return lp3972_set_bits(lp3972, LP3972_VOL_CHANGE_REG,
	455	LP3972_VOL_CHANGE_FLAG_MASK, 0);
	456	}
	457
	458	static struct regulator_ops lp3972_dcdc_ops = {
	459	.list_voltage = lp3972_dcdc_list_voltage,
	460	.is_enabled = lp3972_dcdc_is_enabled,
	461	.enable = lp3972_dcdc_enable,
	462	.disable = lp3972_dcdc_disable,
	463	.get_voltage = lp3972_dcdc_get_voltage,
	464	.set_voltage = lp3972_dcdc_set_voltage,
	465	};
	466
	467	static struct regulator_desc regulators[] = {
	468	{
	469	.name = "LDO1",
	470	.id = LP3972_LDO1,
	471	.ops = &lp3972_ldo_ops,
	472	.n_voltages = ARRAY_SIZE(ldo1_voltage_map),
	473	.type = REGULATOR_VOLTAGE,
	474	.owner = THIS_MODULE,
	475	},
	476	{
477	.name = "LDO2",
478	.id = LP3972_LDO2,
479	.ops = &lp3972_ldo_ops,
480	.n_voltages = ARRAY_SIZE(ldo23_voltage_map),
481	.type = REGULATOR_VOLTAGE,
482	.owner = THIS_MODULE,
483	},
484	{
485	.name = "LDO3",
486	.id = LP3972_LDO3,
487	.ops = &lp3972_ldo_ops,
488	.n_voltages = ARRAY_SIZE(ldo23_voltage_map),
489	.type = REGULATOR_VOLTAGE,
490	.owner = THIS_MODULE,
491	},
492	{
493	.name = "LDO4",
494	.id = LP3972_LDO4,
495	.ops = &lp3972_ldo_ops,
496	.n_voltages = ARRAY_SIZE(ldo4_voltage_map),
497	.type = REGULATOR_VOLTAGE,
498	.owner = THIS_MODULE,
499	},
500	{
501	.name = "LDO5",
502	.id = LP3972_LDO5,
503	.ops = &lp3972_ldo_ops,
504	.n_voltages = ARRAY_SIZE(ldo5_voltage_map),
505	.type = REGULATOR_VOLTAGE,
506	.owner = THIS_MODULE,
507	},
508	{
509	.name = "DCDC1",
510	.id = LP3972_DCDC1,
511	.ops = &lp3972_dcdc_ops,
512	.n_voltages = ARRAY_SIZE(buck1_voltage_map),
513	.type = REGULATOR_VOLTAGE,
514	.owner = THIS_MODULE,
515	},
516	{
517	.name = "DCDC2",
518	.id = LP3972_DCDC2,
519	.ops = &lp3972_dcdc_ops,
520	.n_voltages = ARRAY_SIZE(buck23_voltage_map),
521	.type = REGULATOR_VOLTAGE,
522	.owner = THIS_MODULE,
523	},
524	{
525	.name = "DCDC3",
526	.id = LP3972_DCDC3,
527	.ops = &lp3972_dcdc_ops,
528	.n_voltages = ARRAY_SIZE(buck23_voltage_map),
529	.type = REGULATOR_VOLTAGE,
530	.owner = THIS_MODULE,
531	},
532	};
533
993af7c0	534	static int __devinit setup_regulators(struct lp3972 *lp3972,
5976f095 AL	535	struct lp3972_platform_data *pdata)
	536	{
	537	int i, err;
	538
	539	lp3972->num_regulators = pdata->num_regulators;
	540	lp3972->rdev = kcalloc(pdata->num_regulators,
	541	sizeof(struct regulator_dev *), GFP_KERNEL);
	542	if (!lp3972->rdev) {
	543	err = -ENOMEM;
	544	goto err_nomem;
	545	}
	546
	547	/* Instantiate the regulators */
	548	for (i = 0; i < pdata->num_regulators; i++) {
	549	struct lp3972_regulator_subdev *reg = &pdata->regulators[i];
	550	lp3972->rdev[i] = regulator_register(&regulators[reg->id],
	551	lp3972->dev, reg->initdata, lp3972);
	552
	553	if (IS_ERR(lp3972->rdev[i])) {
	554	err = PTR_ERR(lp3972->rdev[i]);
	555	dev_err(lp3972->dev, "regulator init failed: %d\n",
	556	err);
	557	goto error;
	558	}
	559	}
	560
	561	return 0;
	562	error:
	563	while (--i >= 0)
	564	regulator_unregister(lp3972->rdev[i]);
	565	kfree(lp3972->rdev);
	566	lp3972->rdev = NULL;
	567	err_nomem:
	568	return err;
	569	}
	570
	571	static int __devinit lp3972_i2c_probe(struct i2c_client *i2c,
	572	const struct i2c_device_id *id)
	573	{
	574	struct lp3972 *lp3972;
	575	struct lp3972_platform_data *pdata = i2c->dev.platform_data;
	576	int ret;
	577	u16 val;
	578
	579	if (!pdata) {
	580	dev_dbg(&i2c->dev, "No platform init data supplied\n");
	581	return -ENODEV;
	582	}
	583
	584	lp3972 = kzalloc(sizeof(struct lp3972), GFP_KERNEL);
	585	if (!lp3972)
	586	return -ENOMEM;
	587
	588	lp3972->i2c = i2c;
	589	lp3972->dev = &i2c->dev;
	590
	591	mutex_init(&lp3972->io_lock);
	592
	593	/* Detect LP3972 */
	594	ret = lp3972_i2c_read(i2c, LP3972_SYS_CONTROL1_REG, 1, &val);
993af7c0 AL	595	if (ret == 0 &&
993af7c0 AL	596	(val & SYS_CONTROL1_INIT_MASK) != SYS_CONTROL1_INIT_VAL) {
5976f095	597	ret = -ENODEV;
993af7c0 AL	598	dev_err(&i2c->dev, "chip reported: val = 0x%x\n", val);
993af7c0 AL	599	}
5976f095	600	if (ret < 0) {
993af7c0	601	dev_err(&i2c->dev, "failed to detect device. ret = %d\n", ret);
5976f095 AL	602	goto err_detect;
	603	}
	604
	605	ret = setup_regulators(lp3972, pdata);
	606	if (ret < 0)
	607	goto err_detect;
	608
	609	i2c_set_clientdata(i2c, lp3972);
	610	return 0;
	611
	612	err_detect:
	613	kfree(lp3972);
	614	return ret;
	615	}
	616
	617	static int __devexit lp3972_i2c_remove(struct i2c_client *i2c)
	618	{
	619	struct lp3972 *lp3972 = i2c_get_clientdata(i2c);
	620	int i;
	621
	622	for (i = 0; i < lp3972->num_regulators; i++)
	623	regulator_unregister(lp3972->rdev[i]);
	624	kfree(lp3972->rdev);
	625	kfree(lp3972);
	626
	627	return 0;
	628	}
	629
	630	static const struct i2c_device_id lp3972_i2c_id[] = {
	631	{ "lp3972", 0 },
	632	{ }
	633	};
	634	MODULE_DEVICE_TABLE(i2c, lp3972_i2c_id);
	635
	636	static struct i2c_driver lp3972_i2c_driver = {
	637	.driver = {
	638	.name = "lp3972",
	639	.owner = THIS_MODULE,
	640	},
	641	.probe = lp3972_i2c_probe,
	642	.remove = __devexit_p(lp3972_i2c_remove),
	643	.id_table = lp3972_i2c_id,
	644	};
	645
	646	static int __init lp3972_module_init(void)
	647	{
	648	return i2c_add_driver(&lp3972_i2c_driver);
	649	}
	650	subsys_initcall(lp3972_module_init);
	651
	652	static void __exit lp3972_module_exit(void)
	653	{
	654	i2c_del_driver(&lp3972_i2c_driver);
	655	}
	656	module_exit(lp3972_module_exit);
	657
	658	MODULE_LICENSE("GPL");
	659	MODULE_AUTHOR("Axel Lin <axel.lin@gmail.com>");
	660	MODULE_DESCRIPTION("LP3972 PMIC driver");