diff options
Diffstat (limited to 'drivers/regulator/sy8106a-regulator.c')
| -rw-r--r-- | drivers/regulator/sy8106a-regulator.c | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/drivers/regulator/sy8106a-regulator.c b/drivers/regulator/sy8106a-regulator.c new file mode 100644 index 0000000..65fbd1f --- /dev/null +++ b/drivers/regulator/sy8106a-regulator.c @@ -0,0 +1,167 @@ +// 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"); |
