drivers/regulator/tps51632-regulator.c

   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 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");