/*
* da9210-regulator.c - Regulator device driver for DA9210
* Copyright (C) 2013 Dialog Semiconductor Ltd.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
#include <linux/regulator/of_regulator.h>
#include <linux/regmap.h>
#include "da9210-regulator.h"
struct da9210 {
struct regulator_dev *rdev;
struct regmap *regmap;
};
static const struct regmap_config da9210_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
};
static int da9210_set_current_limit(struct regulator_dev *rdev, int min_uA,
int max_uA);
static int da9210_get_current_limit(struct regulator_dev *rdev);
static struct regulator_ops da9210_buck_ops = {
.enable = regulator_enable_regmap,
.disable = regulator_disable_regmap,
.is_enabled = regulator_is_enabled_regmap,
.set_voltage_sel = regulator_set_voltage_sel_regmap,
.get_voltage_sel = regulator_get_voltage_sel_regmap,
.list_voltage = regulator_list_voltage_linear,
.set_current_limit = da9210_set_current_limit,
.get_current_limit = da9210_get_current_limit,
};
/* Default limits measured in millivolts and milliamps */
#define DA9210_MIN_MV 300
#define DA9210_MAX_MV 1570
#define DA9210_STEP_MV 10
/* Current limits for buck (uA) indices corresponds with register values */
static const int da9210_buck_limits[] = {
1600000, 1800000, 2000000, 2200000, 2400000, 2600000, 2800000, 3000000,
3200000, 3400000, 3600000, 3800000, 4000000, 4200000, 4400000, 4600000
};
static const struct regulator_desc da9210_reg = {
.name = "DA9210",
.id = 0,
.ops = &da9210_buck_ops,
.type = REGULATOR_VOLTAGE,
.n_voltages = ((DA9210_MAX_MV - DA9210_MIN_MV) / DA9210_STEP_MV) + 1,
.min_uV = (DA9210_MIN_MV * 1000),
.uV_step = (DA9210_STEP_MV * 1000),
.vsel_reg = DA9210_REG_VBUCK_A,
.vsel_mask = DA9210_VBUCK_MASK,
.enable_reg = DA9210_REG_BUCK_CONT,
.enable_mask = DA9210_BUCK_EN,
.owner = THIS_MODULE,
};
static int da9210_set_current_limit(struct regulator_dev *rdev, int min_uA,
int max_uA)
{
struct da9210 *chip = rdev_get_drvdata(rdev);
unsigned int sel;
int i;
/* search for closest to maximum */
for (i = ARRAY_SIZE(da9210_buck_limits)-1; i >= 0; i--) {
if (min_uA <= da9210_buck_limits[i] &&
max_uA >= da9210_buck_limits[i]) {
sel = i;
sel = sel << DA9210_BUCK_ILIM_SHIFT;
return regmap_update_bits(chip->regmap,
DA9210_REG_BUCK_ILIM,
DA9210_BUCK_ILIM_MASK, sel);
}
}
return -EINVAL;
}
static int da9210_get_current_limit(struct regulator_dev *rdev)
{
struct da9210 *chip = rdev_get_drvdata(rdev);
unsigned int data;
unsigned int sel;
int ret;
ret = regmap_read(chip->regmap, DA9210_REG_BUCK_ILIM, &data);
if (ret < 0)
return ret;
/* select one of 16 values: 0000 (1600mA) to 1111 (4600mA) */
sel = (data & DA9210_BUCK_ILIM_MASK) >> DA9210_BUCK_ILIM_SHIFT;
return da9210_buck_limits[sel];
}
/*
* I2C driver interface functions
*/
static int da9210_i2c_probe(struct i2c_client *i2c,
const struct i2c_device_id *id)
{
struct da9210 *chip;
struct device *dev = &i2c->dev;
struct da9210_pdata *pdata = dev_get_platdata(dev);
struct regulator_dev *rdev = NULL;
struct regulator_config config = { };
int error;
chip = devm_kzalloc(&i2c->dev, sizeof(struct da9210), GFP_KERNEL);
if (NULL == chip) {
dev_err(&i2c->dev,
"Cannot kzalloc memory for regulator structure\n");
return -ENOMEM;
}
chip->regmap = devm_regmap_init_i2c(i2c, &da9210_regmap_config);
if (IS_ERR(chip->regmap)) {
error = PTR_ERR(chip->regmap);
dev_err(&i2c->dev, "Failed to allocate register map: %d\n",
error);
return error;
}
config.dev = &i2c->dev;
config.init_data = pdata ? &pdata->da9210_constraints :
of_get_regulator_init_data(dev, dev->of_node);
config.driver_data = chip;
config.regmap = chip->regmap;
config.of_node = dev->of_node;
rdev = devm_regulator_register(&i2c->dev, &da9210_reg, &config);
if (IS_ERR(rdev)) {
dev_err(&i2c->dev, "Failed to register DA9210 regulator\n");
return PTR_ERR(rdev);
}
chip->rdev = rdev;
i2c_set_clientdata(i2c, chip);
return 0;
}
static const struct i2c_device_id da9210_i2c_id[] = {
{"da9210", 0},
{},
};
MODULE_DEVICE_TABLE(i2c, da9210_i2c_id);
static struct i2c_driver da9210_regulator_driver = {
.driver = {
.name = "da9210",
.owner = THIS_MODULE,
},
.probe = da9210_i2c_probe,
.id_table = da9210_i2c_id,
};
module_i2c_driver(da9210_regulator_driver);
MODULE_AUTHOR("S Twiss <stwiss.opensource@diasemi.com>");
MODULE_DESCRIPTION("Regulator device driver for Dialog DA9210");
MODULE_LICENSE("GPL v2");
