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; 98 int ret; 99 100 if (ramp_delay == 0) 101 bit = 0; 102 else 103 bit = DIV_ROUND_UP(ramp_delay, 6000) - 1; 104 105 ret = regmap_write(tps->regmap, TPS51632_SLEW_REGS, BIT(bit)); 106 if (ret < 0) 107 dev_err(tps->dev, "SLEW reg write failed, err %d\n", ret); 108 return ret; 109 } 110 111 static const struct regulator_ops tps51632_dcdc_ops = { 112 .get_voltage_sel = regulator_get_voltage_sel_regmap, 113 .set_voltage_sel = regulator_set_voltage_sel_regmap, 114 .list_voltage = regulator_list_voltage_linear, 115 .set_voltage_time_sel = regulator_set_voltage_time_sel, 116 .set_ramp_delay = tps51632_dcdc_set_ramp_delay, 117 }; 118 119 static int tps51632_init_dcdc(struct tps51632_chip *tps, 120 struct tps51632_regulator_platform_data *pdata) 121 { 122 int ret; 123 uint8_t control = 0; 124 int vsel; 125 126 if (!pdata->enable_pwm_dvfs) 127 goto skip_pwm_config; 128 129 control |= TPS51632_DVFS_PWMEN; 130 vsel = TPS51632_VOLT_VSEL(pdata->base_voltage_uV); 131 ret = regmap_write(tps->regmap, TPS51632_VOLTAGE_BASE_REG, vsel); 132 if (ret < 0) { 133 dev_err(tps->dev, "BASE reg write failed, err %d\n", ret); 134 return ret; 135 } 136 137 if (pdata->dvfs_step_20mV) 138 control |= TPS51632_DVFS_STEP_20; 139 140 if (pdata->max_voltage_uV) { 141 unsigned int vmax; 142 /** 143 * TPS51632 hw behavior: VMAX register can be write only 144 * once as it get locked after first write. The lock get 145 * reset only when device is power-reset. 146 * Write register only when lock bit is not enabled. 147 */ 148 ret = regmap_read(tps->regmap, TPS51632_VMAX_REG, &vmax); 149 if (ret < 0) { 150 dev_err(tps->dev, "VMAX read failed, err %d\n", ret); 151 return ret; 152 } 153 if (!(vmax & TPS51632_VMAX_LOCK)) { 154 vsel = TPS51632_VOLT_VSEL(pdata->max_voltage_uV); 155 ret = regmap_write(tps->regmap, TPS51632_VMAX_REG, 156 vsel); 157 if (ret < 0) { 158 dev_err(tps->dev, 159 "VMAX write failed, err %d\n", ret); 160 return ret; 161 } 162 } 163 } 164 165 skip_pwm_config: 166 ret = regmap_write(tps->regmap, TPS51632_DVFS_CONTROL_REG, control); 167 if (ret < 0) 168 dev_err(tps->dev, "DVFS reg write failed, err %d\n", ret); 169 return ret; 170 } 171 172 static bool is_volatile_reg(struct device *dev, unsigned int reg) 173 { 174 switch (reg) { 175 case TPS51632_OFFSET_REG: 176 case TPS51632_FAULT_REG: 177 case TPS51632_IMON_REG: 178 return true; 179 default: 180 return false; 181 } 182 } 183 184 static bool is_read_reg(struct device *dev, unsigned int reg) 185 { 186 switch (reg) { 187 case 0x08 ... 0x0F: 188 return false; 189 default: 190 return true; 191 } 192 } 193 194 static bool is_write_reg(struct device *dev, unsigned int reg) 195 { 196 switch (reg) { 197 case TPS51632_VOLTAGE_SELECT_REG: 198 case TPS51632_VOLTAGE_BASE_REG: 199 case TPS51632_VMAX_REG: 200 case TPS51632_DVFS_CONTROL_REG: 201 case TPS51632_POWER_STATE_REG: 202 case TPS51632_SLEW_REGS: 203 return true; 204 default: 205 return false; 206 } 207 } 208 209 static const struct regmap_config tps51632_regmap_config = { 210 .reg_bits = 8, 211 .val_bits = 8, 212 .writeable_reg = is_write_reg, 213 .readable_reg = is_read_reg, 214 .volatile_reg = is_volatile_reg, 215 .max_register = TPS51632_MAX_REG - 1, 216 .cache_type = REGCACHE_RBTREE, 217 }; 218 219 #if defined(CONFIG_OF) 220 static const struct of_device_id tps51632_of_match[] = { 221 { .compatible = "ti,tps51632",}, 222 {}, 223 }; 224 MODULE_DEVICE_TABLE(of, tps51632_of_match); 225 226 static struct tps51632_regulator_platform_data * 227 of_get_tps51632_platform_data(struct device *dev, 228 const struct regulator_desc *desc) 229 { 230 struct tps51632_regulator_platform_data *pdata; 231 struct device_node *np = dev->of_node; 232 233 pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL); 234 if (!pdata) 235 return NULL; 236 237 pdata->reg_init_data = of_get_regulator_init_data(dev, dev->of_node, 238 desc); 239 if (!pdata->reg_init_data) { 240 dev_err(dev, "Not able to get OF regulator init data\n"); 241 return NULL; 242 } 243 244 pdata->enable_pwm_dvfs = 245 of_property_read_bool(np, "ti,enable-pwm-dvfs"); 246 pdata->dvfs_step_20mV = of_property_read_bool(np, "ti,dvfs-step-20mV"); 247 248 pdata->base_voltage_uV = pdata->reg_init_data->constraints.min_uV ? : 249 TPS51632_MIN_VOLTAGE; 250 pdata->max_voltage_uV = pdata->reg_init_data->constraints.max_uV ? : 251 TPS51632_MAX_VOLTAGE; 252 return pdata; 253 } 254 #else 255 static struct tps51632_regulator_platform_data * 256 of_get_tps51632_platform_data(struct device *dev, 257 const struct regulator_desc *desc) 258 { 259 return NULL; 260 } 261 #endif 262 263 static int tps51632_probe(struct i2c_client *client, 264 const struct i2c_device_id *id) 265 { 266 struct tps51632_regulator_platform_data *pdata; 267 struct regulator_dev *rdev; 268 struct tps51632_chip *tps; 269 int ret; 270 struct regulator_config config = { }; 271 272 if (client->dev.of_node) { 273 const struct of_device_id *match; 274 match = of_match_device(of_match_ptr(tps51632_of_match), 275 &client->dev); 276 if (!match) { 277 dev_err(&client->dev, "Error: No device match found\n"); 278 return -ENODEV; 279 } 280 } 281 282 tps = devm_kzalloc(&client->dev, sizeof(*tps), GFP_KERNEL); 283 if (!tps) 284 return -ENOMEM; 285 286 tps->dev = &client->dev; 287 tps->desc.name = client->name; 288 tps->desc.id = 0; 289 tps->desc.ramp_delay = TPS51632_DEFAULT_RAMP_DELAY; 290 tps->desc.min_uV = TPS51632_MIN_VOLTAGE; 291 tps->desc.uV_step = TPS51632_VOLTAGE_STEP_10mV; 292 tps->desc.linear_min_sel = TPS51632_MIN_VSEL; 293 tps->desc.n_voltages = TPS51632_MAX_VSEL + 1; 294 tps->desc.ops = &tps51632_dcdc_ops; 295 tps->desc.type = REGULATOR_VOLTAGE; 296 tps->desc.owner = THIS_MODULE; 297 298 pdata = dev_get_platdata(&client->dev); 299 if (!pdata && client->dev.of_node) 300 pdata = of_get_tps51632_platform_data(&client->dev, &tps->desc); 301 if (!pdata) { 302 dev_err(&client->dev, "No Platform data\n"); 303 return -EINVAL; 304 } 305 306 if (pdata->enable_pwm_dvfs) { 307 if ((pdata->base_voltage_uV < TPS51632_MIN_VOLTAGE) || 308 (pdata->base_voltage_uV > TPS51632_MAX_VOLTAGE)) { 309 dev_err(&client->dev, "Invalid base_voltage_uV setting\n"); 310 return -EINVAL; 311 } 312 313 if ((pdata->max_voltage_uV) && 314 ((pdata->max_voltage_uV < TPS51632_MIN_VOLTAGE) || 315 (pdata->max_voltage_uV > TPS51632_MAX_VOLTAGE))) { 316 dev_err(&client->dev, "Invalid max_voltage_uV setting\n"); 317 return -EINVAL; 318 } 319 } 320 321 if (pdata->enable_pwm_dvfs) 322 tps->desc.vsel_reg = TPS51632_VOLTAGE_BASE_REG; 323 else 324 tps->desc.vsel_reg = TPS51632_VOLTAGE_SELECT_REG; 325 tps->desc.vsel_mask = TPS51632_VOUT_MASK; 326 327 tps->regmap = devm_regmap_init_i2c(client, &tps51632_regmap_config); 328 if (IS_ERR(tps->regmap)) { 329 ret = PTR_ERR(tps->regmap); 330 dev_err(&client->dev, "regmap init failed, err %d\n", ret); 331 return ret; 332 } 333 i2c_set_clientdata(client, tps); 334 335 ret = tps51632_init_dcdc(tps, pdata); 336 if (ret < 0) { 337 dev_err(tps->dev, "Init failed, err = %d\n", ret); 338 return ret; 339 } 340 341 /* Register the regulators */ 342 config.dev = &client->dev; 343 config.init_data = pdata->reg_init_data; 344 config.driver_data = tps; 345 config.regmap = tps->regmap; 346 config.of_node = client->dev.of_node; 347 348 rdev = devm_regulator_register(&client->dev, &tps->desc, &config); 349 if (IS_ERR(rdev)) { 350 dev_err(tps->dev, "regulator register failed\n"); 351 return PTR_ERR(rdev); 352 } 353 354 tps->rdev = rdev; 355 return 0; 356 } 357 358 static const struct i2c_device_id tps51632_id[] = { 359 {.name = "tps51632",}, 360 {}, 361 }; 362 363 MODULE_DEVICE_TABLE(i2c, tps51632_id); 364 365 static struct i2c_driver tps51632_i2c_driver = { 366 .driver = { 367 .name = "tps51632", 368 .of_match_table = of_match_ptr(tps51632_of_match), 369 }, 370 .probe = tps51632_probe, 371 .id_table = tps51632_id, 372 }; 373 374 static int __init tps51632_init(void) 375 { 376 return i2c_add_driver(&tps51632_i2c_driver); 377 } 378 subsys_initcall(tps51632_init); 379 380 static void __exit tps51632_cleanup(void) 381 { 382 i2c_del_driver(&tps51632_i2c_driver); 383 } 384 module_exit(tps51632_cleanup); 385 386 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>"); 387 MODULE_DESCRIPTION("TPS51632 voltage regulator driver"); 388 MODULE_LICENSE("GPL v2"); 389