linux/drivers/regulator/isl6271a-regulator.c

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/*
* isl6271a-regulator.c
*
* Support for Intersil ISL6271A voltage regulator
*
* Copyright (C) 2010 Marek Vasut <marek.vasut@gmail.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 version 2.
*
* This program is distributed "as is" WITHOUT ANY WARRANTY of any kind,
* whether express or implied; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/i2c.h>
#include <linux/delay.h>
#include <linux/slab.h>
#define ISL6271A_VOLTAGE_MIN 850000
#define ISL6271A_VOLTAGE_MAX 1600000
#define ISL6271A_VOLTAGE_STEP 50000
/* PMIC details */
struct isl_pmic {
struct i2c_client *client;
struct regulator_dev *rdev[3];
struct mutex mtx;
};
static int isl6271a_get_voltage(struct regulator_dev *dev)
{
struct isl_pmic *pmic = rdev_get_drvdata(dev);
int idx, data;
mutex_lock(&pmic->mtx);
idx = i2c_smbus_read_byte(pmic->client);
if (idx < 0) {
dev_err(&pmic->client->dev, "Error getting voltage\n");
data = idx;
goto out;
}
/* Convert the data from chip to microvolts */
data = ISL6271A_VOLTAGE_MIN + (ISL6271A_VOLTAGE_STEP * (idx & 0xf));
out:
mutex_unlock(&pmic->mtx);
return data;
}
static int isl6271a_set_voltage(struct regulator_dev *dev,
int minuV, int maxuV,
unsigned *selector)
{
struct isl_pmic *pmic = rdev_get_drvdata(dev);
int vsel, err, data;
if (minuV < ISL6271A_VOLTAGE_MIN || minuV > ISL6271A_VOLTAGE_MAX)
return -EINVAL;
if (maxuV < ISL6271A_VOLTAGE_MIN || maxuV > ISL6271A_VOLTAGE_MAX)
return -EINVAL;
/* Align to 50000 mV */
vsel = minuV - (minuV % ISL6271A_VOLTAGE_STEP);
/* If the result fell out of [minuV,maxuV] range, put it back */
if (vsel < minuV)
vsel += ISL6271A_VOLTAGE_STEP;
/* Convert the microvolts to data for the chip */
data = (vsel - ISL6271A_VOLTAGE_MIN) / ISL6271A_VOLTAGE_STEP;
*selector = data;
mutex_lock(&pmic->mtx);
err = i2c_smbus_write_byte(pmic->client, data);
if (err < 0)
dev_err(&pmic->client->dev, "Error setting voltage\n");
mutex_unlock(&pmic->mtx);
return err;
}
static int isl6271a_list_voltage(struct regulator_dev *dev, unsigned selector)
{
return ISL6271A_VOLTAGE_MIN + (ISL6271A_VOLTAGE_STEP * selector);
}
static struct regulator_ops isl_core_ops = {
.get_voltage = isl6271a_get_voltage,
.set_voltage = isl6271a_set_voltage,
.list_voltage = isl6271a_list_voltage,
};
static int isl6271a_get_fixed_voltage(struct regulator_dev *dev)
{
int id = rdev_get_id(dev);
return (id == 1) ? 1100000 : 1300000;
}
static int isl6271a_list_fixed_voltage(struct regulator_dev *dev, unsigned selector)
{
int id = rdev_get_id(dev);
return (id == 1) ? 1100000 : 1300000;
}
static struct regulator_ops isl_fixed_ops = {
.get_voltage = isl6271a_get_fixed_voltage,
.list_voltage = isl6271a_list_fixed_voltage,
};
static struct regulator_desc isl_rd[] = {
{
.name = "Core Buck",
.id = 0,
.n_voltages = 16,
.ops = &isl_core_ops,
.type = REGULATOR_VOLTAGE,
.owner = THIS_MODULE,
}, {
.name = "LDO1",
.id = 1,
.n_voltages = 1,
.ops = &isl_fixed_ops,
.type = REGULATOR_VOLTAGE,
.owner = THIS_MODULE,
}, {
.name = "LDO2",
.id = 2,
.n_voltages = 1,
.ops = &isl_fixed_ops,
.type = REGULATOR_VOLTAGE,
.owner = THIS_MODULE,
},
};
static int __devinit isl6271a_probe(struct i2c_client *i2c,
const struct i2c_device_id *id)
{
struct regulator_init_data *init_data = i2c->dev.platform_data;
struct isl_pmic *pmic;
int err, i;
if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
return -EIO;
if (!init_data) {
dev_err(&i2c->dev, "no platform data supplied\n");
return -EIO;
}
pmic = kzalloc(sizeof(struct isl_pmic), GFP_KERNEL);
if (!pmic)
return -ENOMEM;
pmic->client = i2c;
mutex_init(&pmic->mtx);
for (i = 0; i < 3; i++) {
pmic->rdev[i] = regulator_register(&isl_rd[i], &i2c->dev,
init_data, pmic, NULL);
if (IS_ERR(pmic->rdev[i])) {
dev_err(&i2c->dev, "failed to register %s\n", id->name);
err = PTR_ERR(pmic->rdev[i]);
goto error;
}
}
i2c_set_clientdata(i2c, pmic);
return 0;
error:
while (--i >= 0)
regulator_unregister(pmic->rdev[i]);
kfree(pmic);
return err;
}
static int __devexit isl6271a_remove(struct i2c_client *i2c)
{
struct isl_pmic *pmic = i2c_get_clientdata(i2c);
int i;
for (i = 0; i < 3; i++)
regulator_unregister(pmic->rdev[i]);
kfree(pmic);
return 0;
}
static const struct i2c_device_id isl6271a_id[] = {
{.name = "isl6271a", 0 },
{ },
};
MODULE_DEVICE_TABLE(i2c, isl6271a_id);
static struct i2c_driver isl6271a_i2c_driver = {
.driver = {
.name = "isl6271a",
.owner = THIS_MODULE,
},
.probe = isl6271a_probe,
.remove = __devexit_p(isl6271a_remove),
.id_table = isl6271a_id,
};
static int __init isl6271a_init(void)
{
return i2c_add_driver(&isl6271a_i2c_driver);
}
static void __exit isl6271a_cleanup(void)
{
i2c_del_driver(&isl6271a_i2c_driver);
}
subsys_initcall(isl6271a_init);
module_exit(isl6271a_cleanup);
MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
MODULE_DESCRIPTION("Intersil ISL6271A voltage regulator driver");
MODULE_LICENSE("GPL v2");