1 /* 2 * tps51632-regulator.c -- TI TPS51632 3 * 4 * Regulator driver for TPS51632 3-2-1 Phase D-Cap Step Down Driverless 5 * Controller with serial VID control and DVFS. 6 * 7 * Copyright (c) 2012, NVIDIA Corporation. 8 * 9 * Author: Laxman Dewangan <ldewangan@nvidia.com> 10 * 11 * This program is free software; you can redistribute it and/or 12 * modify it under the terms of the GNU General Public License as 13 * published by the Free Software Foundation version 2. 14 * 15 * This program is distributed "as is" WITHOUT ANY WARRANTY of any kind, 16 * whether express or implied; without even the implied warranty of 17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 18 * General Public License for more details. 19 * 20 * You should have received a copy of the GNU General Public License 21 * along with this program; if not, write to the Free Software 22 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 23 * 02111-1307, USA 24 */ 25 26 #include <linux/err.h> 27 #include <linux/i2c.h> 28 #include <linux/init.h> 29 #include <linux/kernel.h> 30 #include <linux/module.h> 31 #include <linux/of.h> 32 #include <linux/of_device.h> 33 #include <linux/platform_device.h> 34 #include <linux/regmap.h> 35 #include <linux/regulator/driver.h> 36 #include <linux/regulator/machine.h> 37 #include <linux/regulator/of_regulator.h> 38 #include <linux/regulator/tps51632-regulator.h> 39 #include <linux/slab.h> 40 41 /* Register definitions */ 42 #define TPS51632_VOLTAGE_SELECT_REG 0x0 43 #define TPS51632_VOLTAGE_BASE_REG 0x1 44 #define TPS51632_OFFSET_REG 0x2 45 #define TPS51632_IMON_REG 0x3 46 #define TPS51632_VMAX_REG 0x4 47 #define TPS51632_DVFS_CONTROL_REG 0x5 48 #define TPS51632_POWER_STATE_REG 0x6 49 #define TPS51632_SLEW_REGS 0x7 50 #define TPS51632_FAULT_REG 0x14 51 52 #define TPS51632_MAX_REG 0x15 53 54 #define TPS51632_VOUT_MASK 0x7F 55 #define TPS51632_VOUT_OFFSET_MASK 0x1F 56 #define TPS51632_VMAX_MASK 0x7F 57 #define TPS51632_VMAX_LOCK 0x80 58 59 /* TPS51632_DVFS_CONTROL_REG */ 60 #define TPS51632_DVFS_PWMEN 0x1 61 #define TPS51632_DVFS_STEP_20 0x2 62 #define TPS51632_DVFS_VMAX_PG 0x4 63 #define TPS51632_DVFS_PWMRST 0x8 64 #define TPS51632_DVFS_OCA_EN 0x10 65 #define TPS51632_DVFS_FCCM 0x20 66 67 /* TPS51632_POWER_STATE_REG */ 68 #define TPS51632_POWER_STATE_MASK 0x03 69 #define TPS51632_POWER_STATE_MULTI_PHASE_CCM 0x0 70 #define TPS51632_POWER_STATE_SINGLE_PHASE_CCM 0x1 71 #define TPS51632_POWER_STATE_SINGLE_PHASE_DCM 0x2 72 73 #define TPS51632_MIN_VOLTAGE 500000 74 #define TPS51632_MAX_VOLTAGE 1520000 75 #define TPS51632_VOLTAGE_STEP_10mV 10000 76 #define TPS51632_VOLTAGE_STEP_20mV 20000 77 #define TPS51632_MAX_VSEL 0x7F 78 #define TPS51632_MIN_VSEL 0x19 79 #define TPS51632_DEFAULT_RAMP_DELAY 6000 80 #define TPS51632_VOLT_VSEL(uV) \ 81 (DIV_ROUND_UP(uV - TPS51632_MIN_VOLTAGE, \ 82 TPS51632_VOLTAGE_STEP_10mV) + \ 83 TPS51632_MIN_VSEL) 84 85 /* TPS51632 chip information */ 86 struct tps51632_chip { 87 struct device *dev; 88 struct regulator_desc desc; 89 struct regulator_dev *rdev; 90 struct regmap *regmap; 91 }; 92 93 static int tps51632_dcdc_set_ramp_delay(struct regulator_dev *rdev, 94 int ramp_delay) 95 { 96 struct tps51632_chip *tps = rdev_get_drvdata(rdev); 97 int bit = ramp_delay/6000; 98 int ret; 99 100 if (bit) 101 bit--; 102 ret = regmap_write(tps->regmap, TPS51632_SLEW_REGS, BIT(bit)); 103 if (ret < 0) 104 dev_err(tps->dev, "SLEW reg write failed, err %d\n", ret); 105 return ret; 106 } 107 108 static struct regulator_ops tps51632_dcdc_ops = { 109 .get_voltage_sel = regulator_get_voltage_sel_regmap, 110 .set_voltage_sel = regulator_set_voltage_sel_regmap, 111 .list_voltage = regulator_list_voltage_linear, 112 .set_voltage_time_sel = regulator_set_voltage_time_sel, 113 .set_ramp_delay = tps51632_dcdc_set_ramp_delay, 114 }; 115 116 static int tps51632_init_dcdc(struct tps51632_chip *tps, 117 struct tps51632_regulator_platform_data *pdata) 118 { 119 int ret; 120 uint8_t control = 0; 121 int vsel; 122 123 if (!pdata->enable_pwm_dvfs) 124 goto skip_pwm_config; 125 126 control |= TPS51632_DVFS_PWMEN; 127 vsel = TPS51632_VOLT_VSEL(pdata->base_voltage_uV); 128 ret = regmap_write(tps->regmap, TPS51632_VOLTAGE_BASE_REG, vsel); 129 if (ret < 0) { 130 dev_err(tps->dev, "BASE reg write failed, err %d\n", ret); 131 return ret; 132 } 133 134 if (pdata->dvfs_step_20mV) 135 control |= TPS51632_DVFS_STEP_20; 136 137 if (pdata->max_voltage_uV) { 138 unsigned int vmax; 139 /** 140 * TPS51632 hw behavior: VMAX register can be write only 141 * once as it get locked after first write. The lock get 142 * reset only when device is power-reset. 143 * Write register only when lock bit is not enabled. 144 */ 145 ret = regmap_read(tps->regmap, TPS51632_VMAX_REG, &vmax); 146 if (ret < 0) { 147 dev_err(tps->dev, "VMAX read failed, err %d\n", ret); 148 return ret; 149 } 150 if (!(vmax & TPS51632_VMAX_LOCK)) { 151 vsel = TPS51632_VOLT_VSEL(pdata->max_voltage_uV); 152 ret = regmap_write(tps->regmap, TPS51632_VMAX_REG, 153 vsel); 154 if (ret < 0) { 155 dev_err(tps->dev, 156 "VMAX write failed, err %d\n", ret); 157 return ret; 158 } 159 } 160 } 161 162 skip_pwm_config: 163 ret = regmap_write(tps->regmap, TPS51632_DVFS_CONTROL_REG, control); 164 if (ret < 0) 165 dev_err(tps->dev, "DVFS reg write failed, err %d\n", ret); 166 return ret; 167 } 168 169 static bool is_volatile_reg(struct device *dev, unsigned int reg) 170 { 171 switch (reg) { 172 case TPS51632_OFFSET_REG: 173 case TPS51632_FAULT_REG: 174 case TPS51632_IMON_REG: 175 return true; 176 default: 177 return false; 178 } 179 } 180 181 static bool is_read_reg(struct device *dev, unsigned int reg) 182 { 183 switch (reg) { 184 case 0x08 ... 0x0F: 185 return false; 186 default: 187 return true; 188 } 189 } 190 191 static bool is_write_reg(struct device *dev, unsigned int reg) 192 { 193 switch (reg) { 194 case TPS51632_VOLTAGE_SELECT_REG: 195 case TPS51632_VOLTAGE_BASE_REG: 196 case TPS51632_VMAX_REG: 197 case TPS51632_DVFS_CONTROL_REG: 198 case TPS51632_POWER_STATE_REG: 199 case TPS51632_SLEW_REGS: 200 return true; 201 default: 202 return false; 203 } 204 } 205 206 static const struct regmap_config tps51632_regmap_config = { 207 .reg_bits = 8, 208 .val_bits = 8, 209 .writeable_reg = is_write_reg, 210 .readable_reg = is_read_reg, 211 .volatile_reg = is_volatile_reg, 212 .max_register = TPS51632_MAX_REG - 1, 213 .cache_type = REGCACHE_RBTREE, 214 }; 215 216 #if defined(CONFIG_OF) 217 static const struct of_device_id tps51632_of_match[] = { 218 { .compatible = "ti,tps51632",}, 219 {}, 220 }; 221 MODULE_DEVICE_TABLE(of, tps51632_of_match); 222 223 static struct tps51632_regulator_platform_data * 224 of_get_tps51632_platform_data(struct device *dev, 225 const struct regulator_desc *desc) 226 { 227 struct tps51632_regulator_platform_data *pdata; 228 struct device_node *np = dev->of_node; 229 230 pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL); 231 if (!pdata) 232 return NULL; 233 234 pdata->reg_init_data = of_get_regulator_init_data(dev, dev->of_node, 235 desc); 236 if (!pdata->reg_init_data) { 237 dev_err(dev, "Not able to get OF regulator init data\n"); 238 return NULL; 239 } 240 241 pdata->enable_pwm_dvfs = 242 of_property_read_bool(np, "ti,enable-pwm-dvfs"); 243 pdata->dvfs_step_20mV = of_property_read_bool(np, "ti,dvfs-step-20mV"); 244 245 pdata->base_voltage_uV = pdata->reg_init_data->constraints.min_uV ? : 246 TPS51632_MIN_VOLTAGE; 247 pdata->max_voltage_uV = pdata->reg_init_data->constraints.max_uV ? : 248 TPS51632_MAX_VOLTAGE; 249 return pdata; 250 } 251 #else 252 static struct tps51632_regulator_platform_data * 253 of_get_tps51632_platform_data(struct device *dev, 254 const struct regulator_desc *desc) 255 { 256 return NULL; 257 } 258 #endif 259 260 static int tps51632_probe(struct i2c_client *client, 261 const struct i2c_device_id *id) 262 { 263 struct tps51632_regulator_platform_data *pdata; 264 struct regulator_dev *rdev; 265 struct tps51632_chip *tps; 266 int ret; 267 struct regulator_config config = { }; 268 269 if (client->dev.of_node) { 270 const struct of_device_id *match; 271 match = of_match_device(of_match_ptr(tps51632_of_match), 272 &client->dev); 273 if (!match) { 274 dev_err(&client->dev, "Error: No device match found\n"); 275 return -ENODEV; 276 } 277 } 278 279 tps = devm_kzalloc(&client->dev, sizeof(*tps), GFP_KERNEL); 280 if (!tps) 281 return -ENOMEM; 282 283 tps->dev = &client->dev; 284 tps->desc.name = client->name; 285 tps->desc.id = 0; 286 tps->desc.ramp_delay = TPS51632_DEFAULT_RAMP_DELAY; 287 tps->desc.min_uV = TPS51632_MIN_VOLTAGE; 288 tps->desc.uV_step = TPS51632_VOLTAGE_STEP_10mV; 289 tps->desc.linear_min_sel = TPS51632_MIN_VSEL; 290 tps->desc.n_voltages = TPS51632_MAX_VSEL + 1; 291 tps->desc.ops = &tps51632_dcdc_ops; 292 tps->desc.type = REGULATOR_VOLTAGE; 293 tps->desc.owner = THIS_MODULE; 294 295 pdata = dev_get_platdata(&client->dev); 296 if (!pdata && client->dev.of_node) 297 pdata = of_get_tps51632_platform_data(&client->dev, &tps->desc); 298 if (!pdata) { 299 dev_err(&client->dev, "No Platform data\n"); 300 return -EINVAL; 301 } 302 303 if (pdata->enable_pwm_dvfs) { 304 if ((pdata->base_voltage_uV < TPS51632_MIN_VOLTAGE) || 305 (pdata->base_voltage_uV > TPS51632_MAX_VOLTAGE)) { 306 dev_err(&client->dev, "Invalid base_voltage_uV setting\n"); 307 return -EINVAL; 308 } 309 310 if ((pdata->max_voltage_uV) && 311 ((pdata->max_voltage_uV < TPS51632_MIN_VOLTAGE) || 312 (pdata->max_voltage_uV > TPS51632_MAX_VOLTAGE))) { 313 dev_err(&client->dev, "Invalid max_voltage_uV setting\n"); 314 return -EINVAL; 315 } 316 } 317 318 if (pdata->enable_pwm_dvfs) 319 tps->desc.vsel_reg = TPS51632_VOLTAGE_BASE_REG; 320 else 321 tps->desc.vsel_reg = TPS51632_VOLTAGE_SELECT_REG; 322 tps->desc.vsel_mask = TPS51632_VOUT_MASK; 323 324 tps->regmap = devm_regmap_init_i2c(client, &tps51632_regmap_config); 325 if (IS_ERR(tps->regmap)) { 326 ret = PTR_ERR(tps->regmap); 327 dev_err(&client->dev, "regmap init failed, err %d\n", ret); 328 return ret; 329 } 330 i2c_set_clientdata(client, tps); 331 332 ret = tps51632_init_dcdc(tps, pdata); 333 if (ret < 0) { 334 dev_err(tps->dev, "Init failed, err = %d\n", ret); 335 return ret; 336 } 337 338 /* Register the regulators */ 339 config.dev = &client->dev; 340 config.init_data = pdata->reg_init_data; 341 config.driver_data = tps; 342 config.regmap = tps->regmap; 343 config.of_node = client->dev.of_node; 344 345 rdev = devm_regulator_register(&client->dev, &tps->desc, &config); 346 if (IS_ERR(rdev)) { 347 dev_err(tps->dev, "regulator register failed\n"); 348 return PTR_ERR(rdev); 349 } 350 351 tps->rdev = rdev; 352 return 0; 353 } 354 355 static const struct i2c_device_id tps51632_id[] = { 356 {.name = "tps51632",}, 357 {}, 358 }; 359 360 MODULE_DEVICE_TABLE(i2c, tps51632_id); 361 362 static struct i2c_driver tps51632_i2c_driver = { 363 .driver = { 364 .name = "tps51632", 365 .of_match_table = of_match_ptr(tps51632_of_match), 366 }, 367 .probe = tps51632_probe, 368 .id_table = tps51632_id, 369 }; 370 371 static int __init tps51632_init(void) 372 { 373 return i2c_add_driver(&tps51632_i2c_driver); 374 } 375 subsys_initcall(tps51632_init); 376 377 static void __exit tps51632_cleanup(void) 378 { 379 i2c_del_driver(&tps51632_i2c_driver); 380 } 381 module_exit(tps51632_cleanup); 382 383 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>"); 384 MODULE_DESCRIPTION("TPS51632 voltage regulator driver"); 385 MODULE_LICENSE("GPL v2"); 386