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 = 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 {
 226         struct tps51632_regulator_platform_data *pdata;
 227         struct device_node *np = dev->of_node;
 228
 229         pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
 230         if (!pdata)
 231                 return NULL;
 232
 233         pdata->reg_init_data = of_get_regulator_init_data(dev, dev->of_node);
 234         if (!pdata->reg_init_data) {
 235                 dev_err(dev, "Not able to get OF regulator init data\n");
 236                 return NULL;
 237         }
 238
 239         pdata->enable_pwm_dvfs =
 240                         of_property_read_bool(np, "ti,enable-pwm-dvfs");
 241         pdata->dvfs_step_20mV = of_property_read_bool(np, "ti,dvfs-step-20mV");
 242
 243         pdata->base_voltage_uV = pdata->reg_init_data->constraints.min_uV ? :
 244                                         TPS51632_MIN_VOLTAGE;
 245         pdata->max_voltage_uV = pdata->reg_init_data->constraints.max_uV ? :
 246                                         TPS51632_MAX_VOLTAGE;
 247         return pdata;
 248 }
 249 #else
 250 static struct tps51632_regulator_platform_data *
 251         of_get_tps51632_platform_data(struct device *dev)
 252 {
 253         return NULL;
 254 }
 255 #endif
 256
 257 static int tps51632_probe(struct i2c_client *client,
 258                                 const struct i2c_device_id *id)
 259 {
 260         struct tps51632_regulator_platform_data *pdata;
 261         struct regulator_dev *rdev;
 262         struct tps51632_chip *tps;
 263         int ret;
 264         struct regulator_config config = { };
 265
 266         if (client->dev.of_node) {
 267                 const struct of_device_id *match;
 268                 match = of_match_device(of_match_ptr(tps51632_of_match),
 269                                 &client->dev);
 270                 if (!match) {
 271                         dev_err(&client->dev, "Error: No device match found\n");
 272                         return -ENODEV;
 273                 }
 274         }
 275
 276         pdata = dev_get_platdata(&client->dev);
 277         if (!pdata && client->dev.of_node)
 278                 pdata = of_get_tps51632_platform_data(&client->dev);
 279         if (!pdata) {
 280                 dev_err(&client->dev, "No Platform data\n");
 281                 return -EINVAL;
 282         }
 283
 284         if (pdata->enable_pwm_dvfs) {
 285                 if ((pdata->base_voltage_uV < TPS51632_MIN_VOLTAGE) ||
 286                     (pdata->base_voltage_uV > TPS51632_MAX_VOLTAGE)) {
 287                         dev_err(&client->dev, "Invalid base_voltage_uV setting\n");
 288                         return -EINVAL;
 289                 }
 290
 291                 if ((pdata->max_voltage_uV) &&
 292                     ((pdata->max_voltage_uV < TPS51632_MIN_VOLTAGE) ||
 293                      (pdata->max_voltage_uV > TPS51632_MAX_VOLTAGE))) {
 294                         dev_err(&client->dev, "Invalid max_voltage_uV setting\n");
 295                         return -EINVAL;
 296                 }
 297         }
 298
 299         tps = devm_kzalloc(&client->dev, sizeof(*tps), GFP_KERNEL);
 300         if (!tps)
 301                 return -ENOMEM;
 302
 303         tps->dev = &client->dev;
 304         tps->desc.name = client->name;
 305         tps->desc.id = 0;
 306         tps->desc.ramp_delay = TPS51632_DEFAULT_RAMP_DELAY;
 307         tps->desc.min_uV = TPS51632_MIN_VOLTAGE;
 308         tps->desc.uV_step = TPS51632_VOLTAGE_STEP_10mV;
 309         tps->desc.linear_min_sel = TPS51632_MIN_VSEL;
 310         tps->desc.n_voltages = TPS51632_MAX_VSEL + 1;
 311         tps->desc.ops = &tps51632_dcdc_ops;
 312         tps->desc.type = REGULATOR_VOLTAGE;
 313         tps->desc.owner = THIS_MODULE;
 314
 315         if (pdata->enable_pwm_dvfs)
 316                 tps->desc.vsel_reg = TPS51632_VOLTAGE_BASE_REG;
 317         else
 318                 tps->desc.vsel_reg = TPS51632_VOLTAGE_SELECT_REG;
 319         tps->desc.vsel_mask = TPS51632_VOUT_MASK;
 320
 321         tps->regmap = devm_regmap_init_i2c(client, &tps51632_regmap_config);
 322         if (IS_ERR(tps->regmap)) {
 323                 ret = PTR_ERR(tps->regmap);
 324                 dev_err(&client->dev, "regmap init failed, err %d\n", ret);
 325                 return ret;
 326         }
 327         i2c_set_clientdata(client, tps);
 328
 329         ret = tps51632_init_dcdc(tps, pdata);
 330         if (ret < 0) {
 331                 dev_err(tps->dev, "Init failed, err = %d\n", ret);
 332                 return ret;
 333         }
 334
 335         /* Register the regulators */
 336         config.dev = &client->dev;
 337         config.init_data = pdata->reg_init_data;
 338         config.driver_data = tps;
 339         config.regmap = tps->regmap;
 340         config.of_node = client->dev.of_node;
 341
 342         rdev = devm_regulator_register(&client->dev, &tps->desc, &config);
 343         if (IS_ERR(rdev)) {
 344                 dev_err(tps->dev, "regulator register failed\n");
 345                 return PTR_ERR(rdev);
 346         }
 347
 348         tps->rdev = rdev;
 349         return 0;
 350 }
 351
 352 static const struct i2c_device_id tps51632_id[] = {
 353         {.name = "tps51632",},
 354         {},
 355 };
 356
 357 MODULE_DEVICE_TABLE(i2c, tps51632_id);
 358
 359 static struct i2c_driver tps51632_i2c_driver = {
 360         .driver = {
 361                 .name = "tps51632",
 362                 .owner = THIS_MODULE,
 363                 .of_match_table = of_match_ptr(tps51632_of_match),
 364         },
 365         .probe = tps51632_probe,
 366         .id_table = tps51632_id,
 367 };
 368
 369 static int __init tps51632_init(void)
 370 {
 371         return i2c_add_driver(&tps51632_i2c_driver);
 372 }
 373 subsys_initcall(tps51632_init);
 374
 375 static void __exit tps51632_cleanup(void)
 376 {
 377         i2c_del_driver(&tps51632_i2c_driver);
 378 }
 379 module_exit(tps51632_cleanup);
 380
 381 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
 382 MODULE_DESCRIPTION("TPS51632 voltage regulator driver");
 383 MODULE_LICENSE("GPL v2");