--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+//
+// AWINIC AW37503 Regulator Driver
+//
+// Copyright (C) 2023 awinic. All Rights Reserved
+//
+// Author: <like@awinic.com>
+
+#include <linux/err.h>
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+
+#define AW37503_REG_VPOS 0x00
+#define AW37503_REG_VNEG 0x01
+#define AW37503_REG_APPS 0x03
+#define AW37503_REG_CONTROL 0x04
+#define AW37503_REG_WPRTEN 0x21
+
+#define AW37503_VOUT_MASK 0x1F
+#define AW37503_VOUT_N_VOLTAGE 0x15
+#define AW37503_VOUT_VMIN 4000000
+#define AW37503_VOUT_VMAX 6000000
+#define AW37503_VOUT_STEP 100000
+
+#define AW37503_REG_APPS_DIS_VPOS BIT(1)
+#define AW37503_REG_APPS_DIS_VNEG BIT(0)
+
+#define AW37503_REGULATOR_ID_VPOS 0
+#define AW37503_REGULATOR_ID_VNEG 1
+#define AW37503_MAX_REGULATORS 2
+
+struct aw37503_reg_pdata {
+ struct gpio_desc *en_gpiod;
+ int ena_gpio_state;
+};
+
+struct aw37503_regulator {
+ struct device *dev;
+ struct aw37503_reg_pdata reg_pdata[AW37503_MAX_REGULATORS];
+};
+
+static int aw37503_regulator_enable(struct regulator_dev *rdev)
+{
+ struct aw37503_regulator *chip = rdev_get_drvdata(rdev);
+ int id = rdev_get_id(rdev);
+ struct aw37503_reg_pdata *rpdata = &chip->reg_pdata[id];
+ int ret;
+
+ if (!IS_ERR(rpdata->en_gpiod)) {
+ gpiod_set_value_cansleep(rpdata->en_gpiod, 1);
+ rpdata->ena_gpio_state = 1;
+ }
+
+ /* Hardware automatically enable discharge bit in enable */
+ if (rdev->constraints->active_discharge ==
+ REGULATOR_ACTIVE_DISCHARGE_DISABLE) {
+ ret = regulator_set_active_discharge_regmap(rdev, false);
+ if (ret < 0) {
+ dev_err(chip->dev, "Failed to disable active discharge: %d\n",
+ ret);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static int aw37503_regulator_disable(struct regulator_dev *rdev)
+{
+ struct aw37503_regulator *chip = rdev_get_drvdata(rdev);
+ int id = rdev_get_id(rdev);
+ struct aw37503_reg_pdata *rpdata = &chip->reg_pdata[id];
+
+ if (!IS_ERR(rpdata->en_gpiod)) {
+ gpiod_set_value_cansleep(rpdata->en_gpiod, 0);
+ rpdata->ena_gpio_state = 0;
+ }
+
+ return 0;
+}
+
+static int aw37503_regulator_is_enabled(struct regulator_dev *rdev)
+{
+ struct aw37503_regulator *chip = rdev_get_drvdata(rdev);
+ int id = rdev_get_id(rdev);
+ struct aw37503_reg_pdata *rpdata = &chip->reg_pdata[id];
+
+ if (!IS_ERR(rpdata->en_gpiod))
+ return rpdata->ena_gpio_state;
+
+ return 1;
+}
+
+static const struct regulator_ops aw37503_regulator_ops = {
+ .enable = aw37503_regulator_enable,
+ .disable = aw37503_regulator_disable,
+ .is_enabled = aw37503_regulator_is_enabled,
+ .list_voltage = regulator_list_voltage_linear,
+ .map_voltage = regulator_map_voltage_linear,
+ .get_voltage_sel = regulator_get_voltage_sel_regmap,
+ .set_voltage_sel = regulator_set_voltage_sel_regmap,
+ .set_active_discharge = regulator_set_active_discharge_regmap,
+};
+
+static int aw37503_of_parse_cb(struct device_node *np,
+ const struct regulator_desc *desc,
+ struct regulator_config *config)
+{
+ struct aw37503_regulator *chip = config->driver_data;
+ struct aw37503_reg_pdata *rpdata = &chip->reg_pdata[desc->id];
+ int ret;
+
+ rpdata->en_gpiod = devm_fwnode_gpiod_get(chip->dev, of_fwnode_handle(np),
+ "enable", GPIOD_OUT_LOW,
+ "enable");
+
+ if (IS_ERR(rpdata->en_gpiod)) {
+ ret = PTR_ERR(rpdata->en_gpiod);
+
+ /* Ignore the error other than probe defer */
+ if (ret == -EPROBE_DEFER)
+ return ret;
+ return 0;
+ }
+
+ return 0;
+}
+
+#define AW37503_REGULATOR_DESC(_id, _name) \
+ [AW37503_REGULATOR_ID_##_id] = { \
+ .name = "aw37503-"#_name, \
+ .supply_name = "vin", \
+ .id = AW37503_REGULATOR_ID_##_id, \
+ .of_match = of_match_ptr(#_name), \
+ .of_parse_cb = aw37503_of_parse_cb, \
+ .ops = &aw37503_regulator_ops, \
+ .n_voltages = AW37503_VOUT_N_VOLTAGE, \
+ .min_uV = AW37503_VOUT_VMIN, \
+ .uV_step = AW37503_VOUT_STEP, \
+ .enable_time = 500, \
+ .vsel_mask = AW37503_VOUT_MASK, \
+ .vsel_reg = AW37503_REG_##_id, \
+ .active_discharge_off = 0, \
+ .active_discharge_on = AW37503_REG_APPS_DIS_##_id, \
+ .active_discharge_mask = AW37503_REG_APPS_DIS_##_id, \
+ .active_discharge_reg = AW37503_REG_APPS, \
+ .type = REGULATOR_VOLTAGE, \
+ .owner = THIS_MODULE, \
+ }
+
+static const struct regulator_desc aw_regs_desc[AW37503_MAX_REGULATORS] = {
+ AW37503_REGULATOR_DESC(VPOS, outp),
+ AW37503_REGULATOR_DESC(VNEG, outn),
+};
+
+static const struct regmap_range aw37503_no_reg_ranges[] = {
+ regmap_reg_range(AW37503_REG_CONTROL + 1,
+ AW37503_REG_WPRTEN - 1),
+};
+
+static const struct regmap_access_table aw37503_no_reg_table = {
+ .no_ranges = aw37503_no_reg_ranges,
+ .n_no_ranges = ARRAY_SIZE(aw37503_no_reg_ranges),
+};
+
+static const struct regmap_config aw37503_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+ .max_register = AW37503_REG_WPRTEN,
+ .rd_table = &aw37503_no_reg_table,
+ .wr_table = &aw37503_no_reg_table,
+};
+
+static int aw37503_probe(struct i2c_client *client)
+{
+ struct device *dev = &client->dev;
+ struct aw37503_regulator *chip;
+ struct regulator_dev *rdev;
+ struct regmap *regmap;
+ struct regulator_config config = { };
+ int id;
+
+ chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
+ if (!chip)
+ return -ENOMEM;
+
+ regmap = devm_regmap_init_i2c(client, &aw37503_regmap_config);
+ if (IS_ERR(regmap))
+ return dev_err_probe(dev, PTR_ERR(regmap),
+ "Failed to init regmap\n");
+
+ i2c_set_clientdata(client, chip);
+ chip->dev = dev;
+
+ config.regmap = regmap;
+ config.dev = dev;
+ config.driver_data = chip;
+
+ for (id = 0; id < AW37503_MAX_REGULATORS; ++id) {
+ rdev = devm_regulator_register(dev, &aw_regs_desc[id],
+ &config);
+ if (IS_ERR(rdev))
+ return dev_err_probe(dev, PTR_ERR(rdev),
+ "Failed to register regulator %s\n",
+ aw_regs_desc[id].name);
+ }
+ return 0;
+}
+
+static const struct i2c_device_id aw37503_id[] = {
+ {.name = "aw37503",},
+ {},
+};
+MODULE_DEVICE_TABLE(i2c, aw37503_id);
+
+static const struct of_device_id aw37503_of_match[] = {
+ {.compatible = "awinic,aw37503",},
+ { /* Sentinel */ },
+};
+
+MODULE_DEVICE_TABLE(of, aw37503_of_match);
+
+static struct i2c_driver aw37503_i2c_driver = {
+ .driver = {
+ .name = "aw37503",
+ .of_match_table = aw37503_of_match,
+ },
+ .probe_new = aw37503_probe,
+ .id_table = aw37503_id,
+};
+
+module_i2c_driver(aw37503_i2c_driver);
+
+MODULE_DESCRIPTION("aw37503 regulator driver");
+MODULE_AUTHOR("Alec Li <like@awinic.com>");
+MODULE_LICENSE("GPL");