diff options
Diffstat (limited to 'drivers/regulator/max1586.c')
| -rw-r--r-- | drivers/regulator/max1586.c | 316 |
1 files changed, 316 insertions, 0 deletions
diff --git a/drivers/regulator/max1586.c b/drivers/regulator/max1586.c new file mode 100644 index 000000000..d4958394e --- /dev/null +++ b/drivers/regulator/max1586.c @@ -0,0 +1,316 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * max1586.c -- Voltage and current regulation for the Maxim 1586 + * + * Copyright (C) 2008 Robert Jarzmik + */ +#include <linux/module.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/platform_device.h> +#include <linux/regulator/driver.h> +#include <linux/slab.h> +#include <linux/regulator/max1586.h> +#include <linux/of_device.h> +#include <linux/regulator/of_regulator.h> + +#define MAX1586_V3_MAX_VSEL 31 +#define MAX1586_V6_MAX_VSEL 3 + +#define MAX1586_V3_MIN_UV 700000 +#define MAX1586_V3_MAX_UV 1475000 + +#define MAX1586_V6_MIN_UV 0 +#define MAX1586_V6_MAX_UV 3000000 + +#define I2C_V3_SELECT (0 << 5) +#define I2C_V6_SELECT (1 << 5) + +struct max1586_data { + struct i2c_client *client; + + /* min/max V3 voltage */ + unsigned int min_uV; + unsigned int max_uV; + + unsigned int v3_curr_sel; + unsigned int v6_curr_sel; +}; + +/* + * V6 voltage + * On I2C bus, sending a "x" byte to the max1586 means : + * set V6 to either 0V, 1.8V, 2.5V, 3V depending on (x & 0x3) + * As regulator framework doesn't accept voltages to be 0V, we use 1uV. + */ +static const unsigned int v6_voltages_uv[] = { 1, 1800000, 2500000, 3000000 }; + +/* + * V3 voltage + * On I2C bus, sending a "x" byte to the max1586 means : + * set V3 to 0.700V + (x & 0x1f) * 0.025V + * This voltage can be increased by external resistors + * R24 and R25=100kOhm as described in the data sheet. + * The gain is approximately: 1 + R24/R25 + R24/185.5kOhm + */ +static int max1586_v3_get_voltage_sel(struct regulator_dev *rdev) +{ + struct max1586_data *max1586 = rdev_get_drvdata(rdev); + + return max1586->v3_curr_sel; +} + +static int max1586_v3_set_voltage_sel(struct regulator_dev *rdev, + unsigned selector) +{ + struct max1586_data *max1586 = rdev_get_drvdata(rdev); + struct i2c_client *client = max1586->client; + int ret; + u8 v3_prog; + + dev_dbg(&client->dev, "changing voltage v3 to %dmv\n", + regulator_list_voltage_linear(rdev, selector) / 1000); + + v3_prog = I2C_V3_SELECT | (u8) selector; + ret = i2c_smbus_write_byte(client, v3_prog); + if (ret) + return ret; + + max1586->v3_curr_sel = selector; + + return 0; +} + +static int max1586_v6_get_voltage_sel(struct regulator_dev *rdev) +{ + struct max1586_data *max1586 = rdev_get_drvdata(rdev); + + return max1586->v6_curr_sel; +} + +static int max1586_v6_set_voltage_sel(struct regulator_dev *rdev, + unsigned int selector) +{ + struct max1586_data *max1586 = rdev_get_drvdata(rdev); + struct i2c_client *client = max1586->client; + u8 v6_prog; + int ret; + + dev_dbg(&client->dev, "changing voltage v6 to %dmv\n", + rdev->desc->volt_table[selector] / 1000); + + v6_prog = I2C_V6_SELECT | (u8) selector; + ret = i2c_smbus_write_byte(client, v6_prog); + if (ret) + return ret; + + max1586->v6_curr_sel = selector; + + return 0; +} + +/* + * The Maxim 1586 controls V3 and V6 voltages, but offers no way of reading back + * the set up value. + */ +static const struct regulator_ops max1586_v3_ops = { + .get_voltage_sel = max1586_v3_get_voltage_sel, + .set_voltage_sel = max1586_v3_set_voltage_sel, + .list_voltage = regulator_list_voltage_linear, + .map_voltage = regulator_map_voltage_linear, +}; + +static const struct regulator_ops max1586_v6_ops = { + .get_voltage_sel = max1586_v6_get_voltage_sel, + .set_voltage_sel = max1586_v6_set_voltage_sel, + .list_voltage = regulator_list_voltage_table, +}; + +static struct regulator_desc max1586_reg[] = { + { + .name = "Output_V3", + .id = MAX1586_V3, + .ops = &max1586_v3_ops, + .type = REGULATOR_VOLTAGE, + .n_voltages = MAX1586_V3_MAX_VSEL + 1, + .owner = THIS_MODULE, + }, + { + .name = "Output_V6", + .id = MAX1586_V6, + .ops = &max1586_v6_ops, + .type = REGULATOR_VOLTAGE, + .n_voltages = MAX1586_V6_MAX_VSEL + 1, + .volt_table = v6_voltages_uv, + .owner = THIS_MODULE, + }, +}; + +static int of_get_max1586_platform_data(struct device *dev, + struct max1586_platform_data *pdata) +{ + struct max1586_subdev_data *sub; + struct of_regulator_match rmatch[ARRAY_SIZE(max1586_reg)] = { }; + struct device_node *np = dev->of_node; + int i, matched; + + if (of_property_read_u32(np, "v3-gain", + &pdata->v3_gain) < 0) { + dev_err(dev, "%pOF has no 'v3-gain' property\n", np); + return -EINVAL; + } + + np = of_get_child_by_name(np, "regulators"); + if (!np) { + dev_err(dev, "missing 'regulators' subnode in DT\n"); + return -EINVAL; + } + + for (i = 0; i < ARRAY_SIZE(rmatch); i++) + rmatch[i].name = max1586_reg[i].name; + + matched = of_regulator_match(dev, np, rmatch, ARRAY_SIZE(rmatch)); + of_node_put(np); + /* + * If matched is 0, ie. neither Output_V3 nor Output_V6 have been found, + * return 0, which signals the normal situation where no subregulator is + * available. This is normal because the max1586 doesn't provide any + * readback support, so the subregulators can't report any status + * anyway. If matched < 0, return the error. + */ + if (matched <= 0) + return matched; + + pdata->subdevs = devm_kcalloc(dev, + matched, + sizeof(struct max1586_subdev_data), + GFP_KERNEL); + if (!pdata->subdevs) + return -ENOMEM; + + pdata->num_subdevs = matched; + sub = pdata->subdevs; + + for (i = 0; i < matched; i++) { + sub->id = i; + sub->name = rmatch[i].of_node->name; + sub->platform_data = rmatch[i].init_data; + sub++; + } + + return 0; +} + +static const struct of_device_id __maybe_unused max1586_of_match[] = { + { .compatible = "maxim,max1586", }, + {}, +}; +MODULE_DEVICE_TABLE(of, max1586_of_match); + +static int max1586_pmic_probe(struct i2c_client *client, + const struct i2c_device_id *i2c_id) +{ + struct max1586_platform_data *pdata, pdata_of; + struct regulator_config config = { }; + struct max1586_data *max1586; + int i, id, ret; + const struct of_device_id *match; + + pdata = dev_get_platdata(&client->dev); + if (client->dev.of_node && !pdata) { + match = of_match_device(of_match_ptr(max1586_of_match), + &client->dev); + if (!match) { + dev_err(&client->dev, "Error: No device match found\n"); + return -ENODEV; + } + ret = of_get_max1586_platform_data(&client->dev, &pdata_of); + if (ret < 0) + return ret; + pdata = &pdata_of; + } + + max1586 = devm_kzalloc(&client->dev, sizeof(struct max1586_data), + GFP_KERNEL); + if (!max1586) + return -ENOMEM; + + max1586->client = client; + + if (!pdata->v3_gain) + return -EINVAL; + + max1586->min_uV = MAX1586_V3_MIN_UV / 1000 * pdata->v3_gain / 1000; + max1586->max_uV = MAX1586_V3_MAX_UV / 1000 * pdata->v3_gain / 1000; + + /* Set curr_sel to default voltage on power-up */ + max1586->v3_curr_sel = 24; /* 1.3V */ + max1586->v6_curr_sel = 0; + + for (i = 0; i < pdata->num_subdevs && i <= MAX1586_V6; i++) { + struct regulator_dev *rdev; + + id = pdata->subdevs[i].id; + if (!pdata->subdevs[i].platform_data) + continue; + if (id < MAX1586_V3 || id > MAX1586_V6) { + dev_err(&client->dev, "invalid regulator id %d\n", id); + return -EINVAL; + } + + if (id == MAX1586_V3) { + max1586_reg[id].min_uV = max1586->min_uV; + max1586_reg[id].uV_step = + (max1586->max_uV - max1586->min_uV) / + MAX1586_V3_MAX_VSEL; + } + + config.dev = &client->dev; + config.init_data = pdata->subdevs[i].platform_data; + config.driver_data = max1586; + + rdev = devm_regulator_register(&client->dev, + &max1586_reg[id], &config); + if (IS_ERR(rdev)) { + dev_err(&client->dev, "failed to register %s\n", + max1586_reg[id].name); + return PTR_ERR(rdev); + } + } + + i2c_set_clientdata(client, max1586); + dev_info(&client->dev, "Maxim 1586 regulator driver loaded\n"); + return 0; +} + +static const struct i2c_device_id max1586_id[] = { + { "max1586", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, max1586_id); + +static struct i2c_driver max1586_pmic_driver = { + .probe = max1586_pmic_probe, + .driver = { + .name = "max1586", + .of_match_table = of_match_ptr(max1586_of_match), + }, + .id_table = max1586_id, +}; + +static int __init max1586_pmic_init(void) +{ + return i2c_add_driver(&max1586_pmic_driver); +} +subsys_initcall(max1586_pmic_init); + +static void __exit max1586_pmic_exit(void) +{ + i2c_del_driver(&max1586_pmic_driver); +} +module_exit(max1586_pmic_exit); + +/* Module information */ +MODULE_DESCRIPTION("MAXIM 1586 voltage regulator driver"); +MODULE_AUTHOR("Robert Jarzmik"); +MODULE_LICENSE("GPL"); |