1 /* 2 * da9210-regulator.c - Regulator device driver for DA9210 3 * Copyright (C) 2013 Dialog Semiconductor Ltd. 4 * 5 * This library is free software; you can redistribute it and/or 6 * modify it under the terms of the GNU Library General Public 7 * License as published by the Free Software Foundation; either 8 * version 2 of the License, or (at your option) any later version. 9 * 10 * This library is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 * Library General Public License for more details. 14 * 15 * You should have received a copy of the GNU Library General Public 16 * License along with this library; if not, write to the 17 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, 18 * Boston, MA 02110-1301, USA. 19 */ 20 21 #include <linux/err.h> 22 #include <linux/i2c.h> 23 #include <linux/module.h> 24 #include <linux/init.h> 25 #include <linux/slab.h> 26 #include <linux/regulator/driver.h> 27 #include <linux/regulator/machine.h> 28 #include <linux/regulator/of_regulator.h> 29 #include <linux/regmap.h> 30 31 #include "da9210-regulator.h" 32 33 struct da9210 { 34 struct regulator_dev *rdev; 35 struct regmap *regmap; 36 }; 37 38 static const struct regmap_config da9210_regmap_config = { 39 .reg_bits = 8, 40 .val_bits = 8, 41 }; 42 43 static int da9210_set_current_limit(struct regulator_dev *rdev, int min_uA, 44 int max_uA); 45 static int da9210_get_current_limit(struct regulator_dev *rdev); 46 47 static struct regulator_ops da9210_buck_ops = { 48 .enable = regulator_enable_regmap, 49 .disable = regulator_disable_regmap, 50 .is_enabled = regulator_is_enabled_regmap, 51 .set_voltage_sel = regulator_set_voltage_sel_regmap, 52 .get_voltage_sel = regulator_get_voltage_sel_regmap, 53 .list_voltage = regulator_list_voltage_linear, 54 .set_current_limit = da9210_set_current_limit, 55 .get_current_limit = da9210_get_current_limit, 56 }; 57 58 /* Default limits measured in millivolts and milliamps */ 59 #define DA9210_MIN_MV 300 60 #define DA9210_MAX_MV 1570 61 #define DA9210_STEP_MV 10 62 63 /* Current limits for buck (uA) indices corresponds with register values */ 64 static const int da9210_buck_limits[] = { 65 1600000, 1800000, 2000000, 2200000, 2400000, 2600000, 2800000, 3000000, 66 3200000, 3400000, 3600000, 3800000, 4000000, 4200000, 4400000, 4600000 67 }; 68 69 static const struct regulator_desc da9210_reg = { 70 .name = "DA9210", 71 .id = 0, 72 .ops = &da9210_buck_ops, 73 .type = REGULATOR_VOLTAGE, 74 .n_voltages = ((DA9210_MAX_MV - DA9210_MIN_MV) / DA9210_STEP_MV) + 1, 75 .min_uV = (DA9210_MIN_MV * 1000), 76 .uV_step = (DA9210_STEP_MV * 1000), 77 .vsel_reg = DA9210_REG_VBUCK_A, 78 .vsel_mask = DA9210_VBUCK_MASK, 79 .enable_reg = DA9210_REG_BUCK_CONT, 80 .enable_mask = DA9210_BUCK_EN, 81 .owner = THIS_MODULE, 82 }; 83 84 static int da9210_set_current_limit(struct regulator_dev *rdev, int min_uA, 85 int max_uA) 86 { 87 struct da9210 *chip = rdev_get_drvdata(rdev); 88 unsigned int sel; 89 int i; 90 91 /* search for closest to maximum */ 92 for (i = ARRAY_SIZE(da9210_buck_limits)-1; i >= 0; i--) { 93 if (min_uA <= da9210_buck_limits[i] && 94 max_uA >= da9210_buck_limits[i]) { 95 sel = i; 96 sel = sel << DA9210_BUCK_ILIM_SHIFT; 97 return regmap_update_bits(chip->regmap, 98 DA9210_REG_BUCK_ILIM, 99 DA9210_BUCK_ILIM_MASK, sel); 100 } 101 } 102 103 return -EINVAL; 104 } 105 106 static int da9210_get_current_limit(struct regulator_dev *rdev) 107 { 108 struct da9210 *chip = rdev_get_drvdata(rdev); 109 unsigned int data; 110 unsigned int sel; 111 int ret; 112 113 ret = regmap_read(chip->regmap, DA9210_REG_BUCK_ILIM, &data); 114 if (ret < 0) 115 return ret; 116 117 /* select one of 16 values: 0000 (1600mA) to 1111 (4600mA) */ 118 sel = (data & DA9210_BUCK_ILIM_MASK) >> DA9210_BUCK_ILIM_SHIFT; 119 120 return da9210_buck_limits[sel]; 121 } 122 123 /* 124 * I2C driver interface functions 125 */ 126 static int da9210_i2c_probe(struct i2c_client *i2c, 127 const struct i2c_device_id *id) 128 { 129 struct da9210 *chip; 130 struct device *dev = &i2c->dev; 131 struct da9210_pdata *pdata = dev_get_platdata(dev); 132 struct regulator_dev *rdev = NULL; 133 struct regulator_config config = { }; 134 int error; 135 136 chip = devm_kzalloc(&i2c->dev, sizeof(struct da9210), GFP_KERNEL); 137 if (!chip) 138 return -ENOMEM; 139 140 chip->regmap = devm_regmap_init_i2c(i2c, &da9210_regmap_config); 141 if (IS_ERR(chip->regmap)) { 142 error = PTR_ERR(chip->regmap); 143 dev_err(&i2c->dev, "Failed to allocate register map: %d\n", 144 error); 145 return error; 146 } 147 148 config.dev = &i2c->dev; 149 config.init_data = pdata ? &pdata->da9210_constraints : 150 of_get_regulator_init_data(dev, dev->of_node); 151 config.driver_data = chip; 152 config.regmap = chip->regmap; 153 config.of_node = dev->of_node; 154 155 rdev = devm_regulator_register(&i2c->dev, &da9210_reg, &config); 156 if (IS_ERR(rdev)) { 157 dev_err(&i2c->dev, "Failed to register DA9210 regulator\n"); 158 return PTR_ERR(rdev); 159 } 160 161 chip->rdev = rdev; 162 163 i2c_set_clientdata(i2c, chip); 164 165 return 0; 166 } 167 168 static const struct i2c_device_id da9210_i2c_id[] = { 169 {"da9210", 0}, 170 {}, 171 }; 172 173 MODULE_DEVICE_TABLE(i2c, da9210_i2c_id); 174 175 static struct i2c_driver da9210_regulator_driver = { 176 .driver = { 177 .name = "da9210", 178 .owner = THIS_MODULE, 179 }, 180 .probe = da9210_i2c_probe, 181 .id_table = da9210_i2c_id, 182 }; 183 184 module_i2c_driver(da9210_regulator_driver); 185 186 MODULE_AUTHOR("S Twiss <stwiss.opensource@diasemi.com>"); 187 MODULE_DESCRIPTION("Regulator device driver for Dialog DA9210"); 188 MODULE_LICENSE("GPL v2"); 189