// SPDX-License-Identifier: GPL-2.0+
//
// sy8106a-regulator.c - Regulator device driver for SY8106A
//
// Copyright (C) 2016 Ondřej Jirman <megous@megous.com>
// Copyright (c) 2017-2018 Icenowy Zheng <icenowy@aosc.io>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/of_regulator.h>
#define SY8106A_REG_VOUT1_SEL 0x01
#define SY8106A_REG_VOUT_COM 0x02
#define SY8106A_REG_VOUT1_SEL_MASK 0x7f
#define SY8106A_DISABLE_REG BIT(0)
/*
* The I2C controlled voltage will only work when this bit is set; otherwise
* it will behave like a fixed regulator.
*/
#define SY8106A_GO_BIT BIT(7)
struct sy8106a {
struct regulator_dev *rdev;
struct regmap *regmap;
u32 fixed_voltage;
};
static const struct regmap_config sy8106a_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
};
static const struct regulator_ops sy8106a_ops = {
.set_voltage_sel = regulator_set_voltage_sel_regmap,
.set_voltage_time_sel = regulator_set_voltage_time_sel,
.get_voltage_sel = regulator_get_voltage_sel_regmap,
.list_voltage = regulator_list_voltage_linear,
/* Enabling/disabling the regulator is not yet implemented */
};
/* Default limits measured in millivolts */
#define SY8106A_MIN_MV 680
#define SY8106A_MAX_MV 1950
#define SY8106A_STEP_MV 10
static const struct regulator_desc sy8106a_reg = {
.name = "SY8106A",
.id = 0,
.ops = &sy8106a_ops,
.type = REGULATOR_VOLTAGE,
.n_voltages = ((SY8106A_MAX_MV - SY8106A_MIN_MV) / SY8106A_STEP_MV) + 1,
.min_uV = (SY8106A_MIN_MV * 1000),
.uV_step = (SY8106A_STEP_MV * 1000),
.vsel_reg = SY8106A_REG_VOUT1_SEL,
.vsel_mask = SY8106A_REG_VOUT1_SEL_MASK,
/*
* This ramp_delay is a conservative default value which works on
* H3/H5 boards VDD-CPUX situations.
*/
.ramp_delay = 200,
.owner = THIS_MODULE,
};
/*
* I2C driver interface functions
*/
static int sy8106a_i2c_probe(struct i2c_client *i2c,
const struct i2c_device_id *id)
{
struct sy8106a *chip;
struct device *dev = &i2c->dev;
struct regulator_dev *rdev = NULL;
struct regulator_config config = { };
unsigned int reg, vsel;
int error;
chip = devm_kzalloc(&i2c->dev, sizeof(struct sy8106a), GFP_KERNEL);
if (!chip)
return -ENOMEM;
error = of_property_read_u32(dev->of_node, "silergy,fixed-microvolt",
&chip->fixed_voltage);
if (error)
return error;
if (chip->fixed_voltage < SY8106A_MIN_MV * 1000 ||
chip->fixed_voltage > SY8106A_MAX_MV * 1000)
return -EINVAL;
chip->regmap = devm_regmap_init_i2c(i2c, &sy8106a_regmap_config);
if (IS_ERR(chip->regmap)) {
error = PTR_ERR(chip->regmap);
dev_err(dev, "Failed to allocate register map: %d\n", error);
return error;
}
config.dev = &i2c->dev;
config.regmap = chip->regmap;
config.driver_data = chip;
config.of_node = dev->of_node;
config.init_data = of_get_regulator_init_data(dev, dev->of_node,
&sy8106a_reg);
if (!config.init_data)
return -ENOMEM;
/* Ensure GO_BIT is enabled when probing */
error = regmap_read(chip->regmap, SY8106A_REG_VOUT1_SEL, ®);
if (error)
return error;
if (!(reg & SY8106A_GO_BIT)) {
vsel = (chip->fixed_voltage / 1000 - SY8106A_MIN_MV) /
SY8106A_STEP_MV;
error = regmap_write(chip->regmap, SY8106A_REG_VOUT1_SEL,
vsel | SY8106A_GO_BIT);
if (error)
return error;
}
/* Probe regulator */
rdev = devm_regulator_register(&i2c->dev, &sy8106a_reg, &config);
if (IS_ERR(rdev)) {
error = PTR_ERR(rdev);
dev_err(&i2c->dev, "Failed to register SY8106A regulator: %d\n", error);
return error;
}
chip->rdev = rdev;
i2c_set_clientdata(i2c, chip);
return 0;
}
static const struct of_device_id sy8106a_i2c_of_match[] = {
{ .compatible = "silergy,sy8106a" },
{ },
};
MODULE_DEVICE_TABLE(of, sy8106a_i2c_of_match);
static const struct i2c_device_id sy8106a_i2c_id[] = {
{ "sy8106a", 0 },
{ },
};
MODULE_DEVICE_TABLE(i2c, sy8106a_i2c_id);
static struct i2c_driver sy8106a_regulator_driver = {
.driver = {
.name = "sy8106a",
.of_match_table = of_match_ptr(sy8106a_i2c_of_match),
},
.probe = sy8106a_i2c_probe,
.id_table = sy8106a_i2c_id,
};
module_i2c_driver(sy8106a_regulator_driver);
MODULE_AUTHOR("Ondřej Jirman <megous@megous.com>");
MODULE_AUTHOR("Icenowy Zheng <icenowy@aosc.io>");
MODULE_DESCRIPTION("Regulator device driver for Silergy SY8106A");
MODULE_LICENSE("GPL");
