blob: 8c09dc71b16db5a92425b97e0e777de4da454f75 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2021, The Linux Foundation. All rights reserved.
* Copyright (c) 2022, Linaro Ltd.
*/
#include <linux/bitfield.h>
#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/of_platform.h>
#include <linux/regmap.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
#include <linux/regulator/of_regulator.h>
#define MAX20411_UV_STEP 6250
#define MAX20411_BASE_UV 243750
#define MAX20411_MIN_SEL 41 /* 0.5V */
#define MAX20411_MAX_SEL 165 /* 1.275V */
#define MAX20411_VID_OFFSET 0x7
#define MAX20411_VID_MASK 0xff
#define MAX20411_SLEW_OFFSET 0x6
#define MAX20411_SLEW_DVS_MASK 0xc
#define MAX20411_SLEW_SR_MASK 0x3
struct max20411 {
struct device *dev;
struct device_node *of_node;
struct regulator_desc desc;
struct regulator_dev *rdev;
struct regmap *regmap;
};
static const unsigned int max20411_slew_rates[] = { 13100, 6600, 3300, 1600 };
static int max20411_enable_time(struct regulator_dev *rdev)
{
int voltage, rate, ret;
unsigned int val;
/* get voltage */
ret = regmap_read(rdev->regmap, rdev->desc->vsel_reg, &val);
if (ret)
return ret;
val &= rdev->desc->vsel_mask;
voltage = regulator_list_voltage_linear(rdev, val);
/* get rate */
ret = regmap_read(rdev->regmap, MAX20411_SLEW_OFFSET, &val);
if (ret)
return ret;
val = FIELD_GET(MAX20411_SLEW_SR_MASK, val);
rate = max20411_slew_rates[val];
return DIV_ROUND_UP(voltage, rate);
}
static const struct regmap_config max20411_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
.max_register = 0xe,
};
static const struct regulator_ops max20411_ops = {
.get_voltage_sel = regulator_get_voltage_sel_regmap,
.set_voltage_sel = regulator_set_voltage_sel_regmap,
.list_voltage = regulator_list_voltage_linear,
.enable_time = max20411_enable_time,
};
static const struct regulator_desc max20411_desc = {
.ops = &max20411_ops,
.owner = THIS_MODULE,
.type = REGULATOR_VOLTAGE,
.supply_name = "vin",
.name = "max20411",
/*
* voltage = 0.24375V + selector * 6.25mV
* with valid selector between 41 to 165 (0.5V to 1.275V)
*/
.min_uV = MAX20411_BASE_UV,
.uV_step = MAX20411_UV_STEP,
.linear_min_sel = MAX20411_MIN_SEL,
.n_voltages = MAX20411_MAX_SEL + 1,
.vsel_reg = MAX20411_VID_OFFSET,
.vsel_mask = MAX20411_VID_MASK,
.ramp_reg = MAX20411_SLEW_OFFSET,
.ramp_mask = MAX20411_SLEW_DVS_MASK,
.ramp_delay_table = max20411_slew_rates,
.n_ramp_values = ARRAY_SIZE(max20411_slew_rates),
};
static int max20411_probe(struct i2c_client *client)
{
struct regulator_init_data *init_data;
struct device *dev = &client->dev;
struct regulator_config cfg = {};
struct max20411 *max20411;
max20411 = devm_kzalloc(dev, sizeof(*max20411), GFP_KERNEL);
if (!max20411)
return -ENOMEM;
max20411->regmap = devm_regmap_init_i2c(client, &max20411_regmap_config);
if (IS_ERR(max20411->regmap)) {
dev_err(dev, "Failed to allocate regmap!\n");
return PTR_ERR(max20411->regmap);
}
max20411->dev = dev;
max20411->of_node = dev->of_node;
max20411->desc = max20411_desc;
init_data = of_get_regulator_init_data(max20411->dev, max20411->of_node, &max20411->desc);
if (!init_data)
return -ENODATA;
cfg.dev = max20411->dev;
cfg.init_data = init_data;
cfg.of_node = max20411->of_node;
cfg.driver_data = max20411;
cfg.ena_gpiod = gpiod_get(max20411->dev, "enable", GPIOD_ASIS);
if (IS_ERR(cfg.ena_gpiod))
return dev_err_probe(dev, PTR_ERR(cfg.ena_gpiod),
"unable to acquire enable gpio\n");
max20411->rdev = devm_regulator_register(max20411->dev, &max20411->desc, &cfg);
if (IS_ERR(max20411->rdev))
dev_err(max20411->dev, "Failed to register regulator\n");
return PTR_ERR_OR_ZERO(max20411->rdev);
}
static const struct of_device_id of_max20411_match_tbl[] = {
{ .compatible = "maxim,max20411", },
{ },
};
MODULE_DEVICE_TABLE(of, of_max20411_match_tbl);
static const struct i2c_device_id max20411_id[] = {
{ "max20411", 0 },
{ },
};
MODULE_DEVICE_TABLE(i2c, max20411_id);
static struct i2c_driver max20411_i2c_driver = {
.driver = {
.name = "max20411",
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
.of_match_table = of_max20411_match_tbl,
},
.probe = max20411_probe,
.id_table = max20411_id,
};
module_i2c_driver(max20411_i2c_driver);
MODULE_LICENSE("GPL");