| /* |
| * max1586.c -- Voltage and current regulation for the Maxim 1586 |
| * |
| * Copyright (C) 2008 Robert Jarzmik |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| */ |
| #include <linux/module.h> |
| #include <linux/err.h> |
| #include <linux/i2c.h> |
| #include <linux/platform_device.h> |
| #include <linux/regulator/driver.h> |
| #include <linux/regulator/max1586.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 */ |
| int min_uV; |
| int max_uV; |
| |
| struct regulator_dev *rdev[0]; |
| }; |
| |
| /* |
| * 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_calc_voltage(struct max1586_data *max1586, |
| unsigned selector) |
| { |
| unsigned range_uV = max1586->max_uV - max1586->min_uV; |
| |
| return max1586->min_uV + (selector * range_uV / MAX1586_V3_MAX_VSEL); |
| } |
| |
| static int max1586_v3_set(struct regulator_dev *rdev, int min_uV, int max_uV) |
| { |
| struct max1586_data *max1586 = rdev_get_drvdata(rdev); |
| struct i2c_client *client = max1586->client; |
| unsigned range_uV = max1586->max_uV - max1586->min_uV; |
| unsigned selector; |
| u8 v3_prog; |
| |
| if (min_uV > max1586->max_uV || max_uV < max1586->min_uV) |
| return -EINVAL; |
| if (min_uV < max1586->min_uV) |
| min_uV = max1586->min_uV; |
| |
| selector = ((min_uV - max1586->min_uV) * MAX1586_V3_MAX_VSEL + |
| range_uV - 1) / range_uV; |
| if (max1586_v3_calc_voltage(max1586, selector) > max_uV) |
| return -EINVAL; |
| |
| dev_dbg(&client->dev, "changing voltage v3 to %dmv\n", |
| max1586_v3_calc_voltage(max1586, selector) / 1000); |
| |
| v3_prog = I2C_V3_SELECT | (u8) selector; |
| return i2c_smbus_write_byte(client, v3_prog); |
| } |
| |
| static int max1586_v3_list(struct regulator_dev *rdev, unsigned selector) |
| { |
| struct max1586_data *max1586 = rdev_get_drvdata(rdev); |
| |
| if (selector > MAX1586_V3_MAX_VSEL) |
| return -EINVAL; |
| return max1586_v3_calc_voltage(max1586, selector); |
| } |
| |
| /* |
| * 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 int max1586_v6_calc_voltage(unsigned selector) |
| { |
| static int voltages_uv[] = { 1, 1800000, 2500000, 3000000 }; |
| |
| return voltages_uv[selector]; |
| } |
| |
| static int max1586_v6_set(struct regulator_dev *rdev, int min_uV, int max_uV) |
| { |
| struct i2c_client *client = rdev_get_drvdata(rdev); |
| unsigned selector; |
| u8 v6_prog; |
| |
| if (min_uV < MAX1586_V6_MIN_UV || min_uV > MAX1586_V6_MAX_UV) |
| return -EINVAL; |
| if (max_uV < MAX1586_V6_MIN_UV || max_uV > MAX1586_V6_MAX_UV) |
| return -EINVAL; |
| |
| if (min_uV >= 3000000) |
| selector = 3; |
| if (min_uV < 3000000) |
| selector = 2; |
| if (min_uV < 2500000) |
| selector = 1; |
| if (min_uV < 1800000) |
| selector = 0; |
| |
| if (max1586_v6_calc_voltage(selector) > max_uV) |
| return -EINVAL; |
| |
| dev_dbg(&client->dev, "changing voltage v6 to %dmv\n", |
| max1586_v6_calc_voltage(selector) / 1000); |
| |
| v6_prog = I2C_V6_SELECT | (u8) selector; |
| return i2c_smbus_write_byte(client, v6_prog); |
| } |
| |
| static int max1586_v6_list(struct regulator_dev *rdev, unsigned selector) |
| { |
| if (selector > MAX1586_V6_MAX_VSEL) |
| return -EINVAL; |
| return max1586_v6_calc_voltage(selector); |
| } |
| |
| /* |
| * The Maxim 1586 controls V3 and V6 voltages, but offers no way of reading back |
| * the set up value. |
| */ |
| static struct regulator_ops max1586_v3_ops = { |
| .set_voltage = max1586_v3_set, |
| .list_voltage = max1586_v3_list, |
| }; |
| |
| static struct regulator_ops max1586_v6_ops = { |
| .set_voltage = max1586_v6_set, |
| .list_voltage = max1586_v6_list, |
| }; |
| |
| 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, |
| .owner = THIS_MODULE, |
| }, |
| }; |
| |
| static int max1586_pmic_probe(struct i2c_client *client, |
| const struct i2c_device_id *i2c_id) |
| { |
| struct regulator_dev **rdev; |
| struct max1586_platform_data *pdata = client->dev.platform_data; |
| struct max1586_data *max1586; |
| int i, id, ret = -ENOMEM; |
| |
| max1586 = kzalloc(sizeof(struct max1586_data) + |
| sizeof(struct regulator_dev *) * (MAX1586_V6 + 1), |
| GFP_KERNEL); |
| if (!max1586) |
| goto out; |
| |
| max1586->client = client; |
| |
| if (!pdata->v3_gain) { |
| ret = -EINVAL; |
| goto out_unmap; |
| } |
| max1586->min_uV = MAX1586_V3_MIN_UV * pdata->v3_gain / 1000000; |
| max1586->max_uV = MAX1586_V3_MAX_UV * pdata->v3_gain / 1000000; |
| |
| rdev = max1586->rdev; |
| for (i = 0; i < pdata->num_subdevs && i <= MAX1586_V6; i++) { |
| 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); |
| goto err; |
| } |
| rdev[i] = regulator_register(&max1586_reg[id], &client->dev, |
| pdata->subdevs[i].platform_data, |
| max1586); |
| if (IS_ERR(rdev[i])) { |
| ret = PTR_ERR(rdev[i]); |
| dev_err(&client->dev, "failed to register %s\n", |
| max1586_reg[id].name); |
| goto err; |
| } |
| } |
| |
| i2c_set_clientdata(client, rdev); |
| dev_info(&client->dev, "Maxim 1586 regulator driver loaded\n"); |
| return 0; |
| |
| err: |
| while (--i >= 0) |
| regulator_unregister(rdev[i]); |
| out_unmap: |
| kfree(max1586); |
| out: |
| return ret; |
| } |
| |
| static int max1586_pmic_remove(struct i2c_client *client) |
| { |
| struct regulator_dev **rdev = i2c_get_clientdata(client); |
| int i; |
| |
| for (i = 0; i <= MAX1586_V6; i++) |
| if (rdev[i]) |
| regulator_unregister(rdev[i]); |
| kfree(rdev); |
| i2c_set_clientdata(client, NULL); |
| |
| 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, |
| .remove = max1586_pmic_remove, |
| .driver = { |
| .name = "max1586", |
| }, |
| .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"); |