256 lines · c
1// SPDX-License-Identifier: GPL-2.0+2 3#include <linux/bitops.h>4#include <linux/delay.h>5#include <linux/gpio/consumer.h>6#include <linux/i2c.h>7#include <linux/kernel.h>8#include <linux/module.h>9#include <linux/regmap.h>10#include <linux/regulator/driver.h>11#include <linux/regulator/of_regulator.h>12 13#define RT6245_VIRT_OCLIMIT 0x0014#define RT6245_VIRT_OTLEVEL 0x0115#define RT6245_VIRT_PGDLYTIME 0x0216#define RT6245_VIRT_SLEWRATE 0x0317#define RT6245_VIRT_SWFREQ 0x0418#define RT6245_VIRT_VOUT 0x0519 20#define RT6245_VOUT_MASK GENMASK(6, 0)21#define RT6245_SLEW_MASK GENMASK(2, 0)22#define RT6245_CHKSUM_MASK BIT(7)23#define RT6245_CODE_MASK GENMASK(6, 0)24 25/* HW Enable + Soft start time */26#define RT6245_ENTIME_IN_US 500027 28#define RT6245_VOUT_MINUV 43750029#define RT6245_VOUT_MAXUV 138750030#define RT6245_VOUT_STEPUV 1250031#define RT6245_NUM_VOUT ((RT6245_VOUT_MAXUV - RT6245_VOUT_MINUV) / RT6245_VOUT_STEPUV + 1)32 33struct rt6245_priv {34 struct gpio_desc *enable_gpio;35 bool enable_state;36};37 38static int rt6245_enable(struct regulator_dev *rdev)39{40 struct rt6245_priv *priv = rdev_get_drvdata(rdev);41 struct regmap *regmap = rdev_get_regmap(rdev);42 int ret;43 44 if (!priv->enable_gpio)45 return 0;46 47 gpiod_direction_output(priv->enable_gpio, 1);48 usleep_range(RT6245_ENTIME_IN_US, RT6245_ENTIME_IN_US + 1000);49 50 regcache_cache_only(regmap, false);51 ret = regcache_sync(regmap);52 if (ret)53 return ret;54 55 priv->enable_state = true;56 return 0;57}58 59static int rt6245_disable(struct regulator_dev *rdev)60{61 struct rt6245_priv *priv = rdev_get_drvdata(rdev);62 struct regmap *regmap = rdev_get_regmap(rdev);63 64 if (!priv->enable_gpio)65 return -EINVAL;66 67 regcache_cache_only(regmap, true);68 regcache_mark_dirty(regmap);69 70 gpiod_direction_output(priv->enable_gpio, 0);71 72 priv->enable_state = false;73 return 0;74}75 76static int rt6245_is_enabled(struct regulator_dev *rdev)77{78 struct rt6245_priv *priv = rdev_get_drvdata(rdev);79 80 return priv->enable_state ? 1 : 0;81}82 83static const struct regulator_ops rt6245_regulator_ops = {84 .list_voltage = regulator_list_voltage_linear,85 .set_voltage_sel = regulator_set_voltage_sel_regmap,86 .get_voltage_sel = regulator_get_voltage_sel_regmap,87 .set_ramp_delay = regulator_set_ramp_delay_regmap,88 .enable = rt6245_enable,89 .disable = rt6245_disable,90 .is_enabled = rt6245_is_enabled,91};92 93/* ramp delay dividend is 12500 uV/uS, and divisor from 1 to 8 */94static const unsigned int rt6245_ramp_delay_table[] = {95 12500, 6250, 4167, 3125, 2500, 2083, 1786, 156296};97 98static const struct regulator_desc rt6245_regulator_desc = {99 .name = "rt6245-regulator",100 .ops = &rt6245_regulator_ops,101 .type = REGULATOR_VOLTAGE,102 .min_uV = RT6245_VOUT_MINUV,103 .uV_step = RT6245_VOUT_STEPUV,104 .n_voltages = RT6245_NUM_VOUT,105 .ramp_delay_table = rt6245_ramp_delay_table,106 .n_ramp_values = ARRAY_SIZE(rt6245_ramp_delay_table),107 .owner = THIS_MODULE,108 .vsel_reg = RT6245_VIRT_VOUT,109 .vsel_mask = RT6245_VOUT_MASK,110 .ramp_reg = RT6245_VIRT_SLEWRATE,111 .ramp_mask = RT6245_SLEW_MASK,112};113 114static int rt6245_init_device_properties(struct device *dev)115{116 const struct {117 const char *name;118 unsigned int reg;119 } rt6245_props[] = {120 { "richtek,oc-level-select", RT6245_VIRT_OCLIMIT },121 { "richtek,ot-level-select", RT6245_VIRT_OTLEVEL },122 { "richtek,pgdly-time-select", RT6245_VIRT_PGDLYTIME },123 { "richtek,switch-freq-select", RT6245_VIRT_SWFREQ }124 };125 struct regmap *regmap = dev_get_regmap(dev, NULL);126 u8 propval;127 int i, ret;128 129 for (i = 0; i < ARRAY_SIZE(rt6245_props); i++) {130 ret = device_property_read_u8(dev, rt6245_props[i].name, &propval);131 if (ret)132 continue;133 134 ret = regmap_write(regmap, rt6245_props[i].reg, propval);135 if (ret) {136 dev_err(dev, "Fail to apply [%s:%d]\n", rt6245_props[i].name, propval);137 return ret;138 }139 }140 141 return 0;142}143 144static int rt6245_reg_write(void *context, unsigned int reg, unsigned int val)145{146 struct i2c_client *i2c = context;147 static const u8 func_base[] = { 0x6F, 0x73, 0x78, 0x61, 0x7C, 0 };148 unsigned int code, bit_count;149 150 code = func_base[reg];151 code += val;152 153 /* xor checksum for bit 6 to 0 */154 bit_count = hweight8(code & RT6245_CODE_MASK);155 if (bit_count % 2)156 code |= RT6245_CHKSUM_MASK;157 else158 code &= ~RT6245_CHKSUM_MASK;159 160 return i2c_smbus_write_byte(i2c, code);161}162 163static const struct reg_default rt6245_reg_defaults[] = {164 /* Default over current 14A */165 { RT6245_VIRT_OCLIMIT, 2 },166 /* Default over temperature 150'c */167 { RT6245_VIRT_OTLEVEL, 0 },168 /* Default power good delay time 10us */169 { RT6245_VIRT_PGDLYTIME, 1 },170 /* Default slewrate 12.5mV/uS */171 { RT6245_VIRT_SLEWRATE, 0 },172 /* Default switch frequency 800KHz */173 { RT6245_VIRT_SWFREQ, 1 },174 /* Default voltage 750mV */175 { RT6245_VIRT_VOUT, 0x19 }176};177 178static const struct regmap_config rt6245_regmap_config = {179 .reg_bits = 8,180 .val_bits = 8,181 .max_register = RT6245_VIRT_VOUT,182 .cache_type = REGCACHE_FLAT,183 .reg_defaults = rt6245_reg_defaults,184 .num_reg_defaults = ARRAY_SIZE(rt6245_reg_defaults),185 .reg_write = rt6245_reg_write,186};187 188static int rt6245_probe(struct i2c_client *i2c)189{190 struct rt6245_priv *priv;191 struct regmap *regmap;192 struct regulator_config regulator_cfg = {};193 struct regulator_dev *rdev;194 int ret;195 196 priv = devm_kzalloc(&i2c->dev, sizeof(*priv), GFP_KERNEL);197 if (!priv)198 return -ENOMEM;199 200 priv->enable_state = true;201 202 priv->enable_gpio = devm_gpiod_get_optional(&i2c->dev, "enable", GPIOD_OUT_HIGH);203 if (IS_ERR(priv->enable_gpio)) {204 dev_err(&i2c->dev, "Failed to get 'enable' gpio\n");205 return PTR_ERR(priv->enable_gpio);206 }207 208 usleep_range(RT6245_ENTIME_IN_US, RT6245_ENTIME_IN_US + 1000);209 210 regmap = devm_regmap_init(&i2c->dev, NULL, i2c, &rt6245_regmap_config);211 if (IS_ERR(regmap)) {212 dev_err(&i2c->dev, "Failed to initialize the regmap\n");213 return PTR_ERR(regmap);214 }215 216 ret = rt6245_init_device_properties(&i2c->dev);217 if (ret) {218 dev_err(&i2c->dev, "Failed to initialize device properties\n");219 return ret;220 }221 222 regulator_cfg.dev = &i2c->dev;223 regulator_cfg.of_node = i2c->dev.of_node;224 regulator_cfg.regmap = regmap;225 regulator_cfg.driver_data = priv;226 regulator_cfg.init_data = of_get_regulator_init_data(&i2c->dev, i2c->dev.of_node,227 &rt6245_regulator_desc);228 rdev = devm_regulator_register(&i2c->dev, &rt6245_regulator_desc, ®ulator_cfg);229 if (IS_ERR(rdev)) {230 dev_err(&i2c->dev, "Failed to register regulator\n");231 return PTR_ERR(rdev);232 }233 234 return 0;235}236 237static const struct of_device_id __maybe_unused rt6245_of_match_table[] = {238 { .compatible = "richtek,rt6245", },239 {}240};241MODULE_DEVICE_TABLE(of, rt6245_of_match_table);242 243static struct i2c_driver rt6245_driver = {244 .driver = {245 .name = "rt6245",246 .probe_type = PROBE_PREFER_ASYNCHRONOUS,247 .of_match_table = rt6245_of_match_table,248 },249 .probe = rt6245_probe,250};251module_i2c_driver(rt6245_driver);252 253MODULE_AUTHOR("ChiYuan Huang <cy_huang@richtek.com>");254MODULE_DESCRIPTION("Richtek RT6245 Regulator Driver");255MODULE_LICENSE("GPL v2");256