// SPDX-License-Identifier: GPL-2.0+
#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/regmap.h>
#include <linux/regulator/driver.h>
#define RT4801_REG_VOP 0x00
#define RT4801_REG_VON 0x01
#define RT4801_REG_APPS 0x03
#define VOUT_MASK 0x1F
#define MIN_UV 4000000
#define STEP_UV 100000
#define MAX_UV 6000000
#define N_VOLTAGES ((MAX_UV - MIN_UV) / STEP_UV + 1)
#define DSV_OUT_POS 0
#define DSV_OUT_NEG 1
#define DSV_OUT_MAX 2
#define DSVP_ENABLE BIT(0)
#define DSVN_ENABLE BIT(1)
#define DSVALL_ENABLE (DSVP_ENABLE | DSVN_ENABLE)
struct rt4801_priv {
struct device *dev;
struct gpio_desc *enable_gpios[DSV_OUT_MAX];
unsigned int enable_flag;
unsigned int volt_sel[DSV_OUT_MAX];
};
static int rt4801_of_parse_cb(struct device_node *np,
const struct regulator_desc *desc,
struct regulator_config *config)
{
struct rt4801_priv *priv = config->driver_data;
int id = desc->id;
if (priv->enable_gpios[id]) {
dev_warn(priv->dev, "duplicated enable-gpios property\n");
return 0;
}
priv->enable_gpios[id] = devm_fwnode_gpiod_get_index(priv->dev,
of_fwnode_handle(np),
"enable", 0,
GPIOD_OUT_HIGH,
"rt4801");
if (IS_ERR(priv->enable_gpios[id]))
priv->enable_gpios[id] = NULL;
return 0;
}
static int rt4801_set_voltage_sel(struct regulator_dev *rdev, unsigned int selector)
{
struct rt4801_priv *priv = rdev_get_drvdata(rdev);
int id = rdev_get_id(rdev), ret;
if (priv->enable_flag & BIT(id)) {
ret = regulator_set_voltage_sel_regmap(rdev, selector);
if (ret)
return ret;
}
priv->volt_sel[id] = selector;
return 0;
}
static int rt4801_get_voltage_sel(struct regulator_dev *rdev)
{
struct rt4801_priv *priv = rdev_get_drvdata(rdev);
int id = rdev_get_id(rdev);
if (priv->enable_flag & BIT(id))
return regulator_get_voltage_sel_regmap(rdev);
return priv->volt_sel[id];
}
static int rt4801_enable(struct regulator_dev *rdev)
{
struct rt4801_priv *priv = rdev_get_drvdata(rdev);
int id = rdev_get_id(rdev), ret;
if (!priv->enable_gpios[id]) {
dev_warn(&rdev->dev, "no dedicated gpio can control\n");
goto bypass_gpio;
}
gpiod_set_value(priv->enable_gpios[id], 1);
bypass_gpio:
ret = regmap_write(rdev->regmap, rdev->desc->vsel_reg, priv->volt_sel[id]);
if (ret)
return ret;
priv->enable_flag |= BIT(id);
return 0;
}
static int rt4801_disable(struct regulator_dev *rdev)
{
struct rt4801_priv *priv = rdev_get_drvdata(rdev);
int id = rdev_get_id(rdev);
if (!priv->enable_gpios[id]) {
dev_warn(&rdev->dev, "no dedicated gpio can control\n");
goto bypass_gpio;
}
gpiod_set_value(priv->enable_gpios[id], 0);
bypass_gpio:
priv->enable_flag &= ~BIT(id);
return 0;
}
static int rt4801_is_enabled(struct regulator_dev *rdev)
{
struct rt4801_priv *priv = rdev_get_drvdata(rdev);
int id = rdev_get_id(rdev);
return !!(priv->enable_flag & BIT(id));
}
static const struct regulator_ops rt4801_regulator_ops = {
.list_voltage = regulator_list_voltage_linear,
.set_voltage_sel = rt4801_set_voltage_sel,
.get_voltage_sel = rt4801_get_voltage_sel,
.enable = rt4801_enable,
.disable = rt4801_disable,
.is_enabled = rt4801_is_enabled,
};
static const struct regulator_desc rt4801_regulator_descs[] = {
{
.name = "DSVP",
.ops = &rt4801_regulator_ops,
.of_match = of_match_ptr("DSVP"),
.of_parse_cb = rt4801_of_parse_cb,
.type = REGULATOR_VOLTAGE,
.id = DSV_OUT_POS,
.min_uV = MIN_UV,
.uV_step = STEP_UV,
.n_voltages = N_VOLTAGES,
.owner = THIS_MODULE,
.vsel_reg = RT4801_REG_VOP,
.vsel_mask = VOUT_MASK,
},
{
.name = "DSVN",
.ops = &rt4801_regulator_ops,
.of_match = of_match_ptr("DSVN"),
.of_parse_cb = rt4801_of_parse_cb,
.type = REGULATOR_VOLTAGE,
.id = DSV_OUT_NEG,
.min_uV = MIN_UV,
.uV_step = STEP_UV,
.n_voltages = N_VOLTAGES,
.owner = THIS_MODULE,
.vsel_reg = RT4801_REG_VON,
.vsel_mask = VOUT_MASK,
},
};
static const struct regmap_config rt4801_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
.max_register = RT4801_REG_APPS,
};
static int rt4801_probe(struct i2c_client *i2c)
{
struct rt4801_priv *priv;
struct regmap *regmap;
int i;
priv = devm_kzalloc(&i2c->dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
priv->dev = &i2c->dev;
/* bootloader will on, driver only reconfigure enable to all output high */
priv->enable_flag = DSVALL_ENABLE;
regmap = devm_regmap_init_i2c(i2c, &rt4801_regmap_config);
if (IS_ERR(regmap)) {
dev_err(&i2c->dev, "Failed to init regmap\n");
return PTR_ERR(regmap);
}
for (i = 0; i < DSV_OUT_MAX; i++) {
priv->enable_gpios[i] = devm_gpiod_get_index_optional(&i2c->dev,
"enable",
i,
GPIOD_OUT_HIGH);
if (IS_ERR(priv->enable_gpios[i])) {
dev_err(&i2c->dev, "Failed to get gpios\n");
return PTR_ERR(priv->enable_gpios[i]);
}
}
for (i = 0; i < DSV_OUT_MAX; i++) {
const struct regulator_desc *desc = rt4801_regulator_descs + i;
struct regulator_config config = { .dev = &i2c->dev, .driver_data = priv,
.regmap = regmap, };
struct regulator_dev *rdev;
unsigned int val;
int ret;
/* initialize volt_sel variable */
ret = regmap_read(regmap, desc->vsel_reg, &val);
if (ret)
return ret;
priv->volt_sel[i] = val & desc->vsel_mask;
rdev = devm_regulator_register(&i2c->dev, desc, &config);
if (IS_ERR(rdev)) {
dev_err(&i2c->dev, "Failed to register [%d] regulator\n", i);
return PTR_ERR(rdev);
}
}
return 0;
}
static const struct of_device_id __maybe_unused rt4801_of_id[] = {
{ .compatible = "richtek,rt4801", },
{ },
};
MODULE_DEVICE_TABLE(of, rt4801_of_id);
static struct i2c_driver rt4801_driver = {
.driver = {
.name = "rt4801",
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
.of_match_table = of_match_ptr(rt4801_of_id),
},
.probe = rt4801_probe,
};
module_i2c_driver(rt4801_driver);
MODULE_AUTHOR("ChiYuan Hwang <[email protected]>");
MODULE_DESCRIPTION("Richtek RT4801 Display Bias Driver");
MODULE_LICENSE("GPL v2");
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