linux/drivers/regulator/tps51632-regulator.c
<<
>>
Prefs
   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 */
  86struct tps51632_chip {
  87        struct device *dev;
  88        struct regulator_desc desc;
  89        struct regulator_dev *rdev;
  90        struct regmap *regmap;
  91};
  92
  93static 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
 111static 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
 119static 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
 165skip_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
 172static 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
 184static 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
 194static 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
 209static 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)
 220static const struct of_device_id tps51632_of_match[] = {
 221        { .compatible = "ti,tps51632",},
 222        {},
 223};
 224MODULE_DEVICE_TABLE(of, tps51632_of_match);
 225
 226static 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
 255static 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
 263static 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
 358static const struct i2c_device_id tps51632_id[] = {
 359        {.name = "tps51632",},
 360        {},
 361};
 362
 363MODULE_DEVICE_TABLE(i2c, tps51632_id);
 364
 365static 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
 374static int __init tps51632_init(void)
 375{
 376        return i2c_add_driver(&tps51632_i2c_driver);
 377}
 378subsys_initcall(tps51632_init);
 379
 380static void __exit tps51632_cleanup(void)
 381{
 382        i2c_del_driver(&tps51632_i2c_driver);
 383}
 384module_exit(tps51632_cleanup);
 385
 386MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
 387MODULE_DESCRIPTION("TPS51632 voltage regulator driver");
 388MODULE_LICENSE("GPL v2");
 389