drivers/regulator/rk808-regulator.c

   1 /*
   2  * Regulator driver for Rockchip RK808
   3  *
   4  * Copyright (c) 2014, Fuzhou Rockchip Electronics Co., Ltd
   5  *
   6  * Author: Chris Zhong <zyw@rock-chips.com>
   7  * Author: Zhang Qing <zhangqing@rock-chips.com>
   8  *
   9  * This program is free software; you can redistribute it and/or modify it
  10  * under the terms and conditions of the GNU General Public License,
  11  * version 2, as published by the Free Software Foundation.
  12  *
  13  * This program is distributed in the hope it will be useful, but WITHOUT
  14  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  16  * more details.
  17  */
  18
  19 #include <linux/delay.h>
  20 #include <linux/gpio.h>
  21 #include <linux/i2c.h>
  22 #include <linux/module.h>
  23 #include <linux/of_device.h>
  24 #include <linux/of_gpio.h>
  25 #include <linux/mfd/rk808.h>
  26 #include <linux/regulator/driver.h>
  27 #include <linux/regulator/of_regulator.h>
  28 #include <linux/gpio/consumer.h>
  29
  30 /* Field Definitions */
  31 #define RK808_BUCK_VSEL_MASK    0x3f
  32 #define RK808_BUCK4_VSEL_MASK   0xf
  33 #define RK808_LDO_VSEL_MASK     0x1f
  34
  35 /* Ramp rate definitions for buck1 / buck2 only */
  36 #define RK808_RAMP_RATE_OFFSET          3
  37 #define RK808_RAMP_RATE_MASK            (3 << RK808_RAMP_RATE_OFFSET)
  38 #define RK808_RAMP_RATE_2MV_PER_US      (0 << RK808_RAMP_RATE_OFFSET)
  39 #define RK808_RAMP_RATE_4MV_PER_US      (1 << RK808_RAMP_RATE_OFFSET)
  40 #define RK808_RAMP_RATE_6MV_PER_US      (2 << RK808_RAMP_RATE_OFFSET)
  41 #define RK808_RAMP_RATE_10MV_PER_US     (3 << RK808_RAMP_RATE_OFFSET)
  42
  43 #define RK808_DVS2_POL          BIT(2)
  44 #define RK808_DVS1_POL          BIT(1)
  45
  46 /* Offset from XXX_ON_VSEL to XXX_SLP_VSEL */
  47 #define RK808_SLP_REG_OFFSET 1
  48
  49 /* Offset from XXX_ON_VSEL to XXX_DVS_VSEL */
  50 #define RK808_DVS_REG_OFFSET 2
  51
  52 /* Offset from XXX_EN_REG to SLEEP_SET_OFF_XXX */
  53 #define RK808_SLP_SET_OFF_REG_OFFSET 2
  54
  55 /* max steps for increase voltage of Buck1/2, equal 100mv*/
  56 #define MAX_STEPS_ONE_TIME 8
  57
  58 #define RK8XX_DESC(_id, _match, _supply, _min, _max, _step, _vreg,      \
  59         _vmask, _ereg, _emask, _etime)                                  \
  60         [_id] = {                                                       \
  61                 .name           = (_match),                             \
  62                 .supply_name    = (_supply),                            \
  63                 .of_match       = of_match_ptr(_match),                 \
  64                 .regulators_node = of_match_ptr("regulators"),          \
  65                 .type           = REGULATOR_VOLTAGE,                    \
  66                 .id             = (_id),                                \
  67                 .n_voltages     = (((_max) - (_min)) / (_step) + 1),    \
  68                 .owner          = THIS_MODULE,                          \
  69                 .min_uV         = (_min) * 1000,                        \
  70                 .uV_step        = (_step) * 1000,                       \
  71                 .vsel_reg       = (_vreg),                              \
  72                 .vsel_mask      = (_vmask),                             \
  73                 .enable_reg     = (_ereg),                              \
  74                 .enable_mask    = (_emask),                             \
  75                 .enable_time    = (_etime),                             \
  76                 .ops            = &rk808_reg_ops,                       \
  77         }
  78
  79 #define RK8XX_DESC_SWITCH(_id, _match, _supply, _ereg, _emask)          \
  80         [_id] = {                                                       \
  81                 .name           = (_match),                             \
  82                 .supply_name    = (_supply),                            \
  83                 .of_match       = of_match_ptr(_match),                 \
  84                 .regulators_node = of_match_ptr("regulators"),          \
  85                 .type           = REGULATOR_VOLTAGE,                    \
  86                 .id             = (_id),                                \
  87                 .enable_reg     = (_ereg),                              \
  88                 .enable_mask    = (_emask),                             \
  89                 .owner          = THIS_MODULE,                          \
  90                 .ops            = &rk808_switch_ops                     \
  91         }
  92
  93
  94 struct rk808_regulator_data {
  95         struct gpio_desc *dvs_gpio[2];
  96 };
  97
  98 static const int rk808_buck_config_regs[] = {
  99         RK808_BUCK1_CONFIG_REG,
 100         RK808_BUCK2_CONFIG_REG,
 101         RK808_BUCK3_CONFIG_REG,
 102         RK808_BUCK4_CONFIG_REG,
 103 };
 104
 105 static const struct regulator_linear_range rk808_ldo3_voltage_ranges[] = {
 106         REGULATOR_LINEAR_RANGE(800000, 0, 13, 100000),
 107         REGULATOR_LINEAR_RANGE(2500000, 15, 15, 0),
 108 };
 109
 110 static int rk808_buck1_2_get_voltage_sel_regmap(struct regulator_dev *rdev)
 111 {
 112         struct rk808_regulator_data *pdata = rdev_get_drvdata(rdev);
 113         int id = rdev->desc->id - RK808_ID_DCDC1;
 114         struct gpio_desc *gpio = pdata->dvs_gpio[id];
 115         unsigned int val;
 116         int ret;
 117
 118         if (!gpio || gpiod_get_value(gpio) == 0)
 119                 return regulator_get_voltage_sel_regmap(rdev);
 120
 121         ret = regmap_read(rdev->regmap,
 122                           rdev->desc->vsel_reg + RK808_DVS_REG_OFFSET,
 123                           &val);
 124         if (ret != 0)
 125                 return ret;
 126
 127         val &= rdev->desc->vsel_mask;
 128         val >>= ffs(rdev->desc->vsel_mask) - 1;
 129
 130         return val;
 131 }
 132
 133 static int rk808_buck1_2_i2c_set_voltage_sel(struct regulator_dev *rdev,
 134                                              unsigned sel)
 135 {
 136         int ret, delta_sel;
 137         unsigned int old_sel, tmp, val, mask = rdev->desc->vsel_mask;
 138
 139         ret = regmap_read(rdev->regmap, rdev->desc->vsel_reg, &val);
 140         if (ret != 0)
 141                 return ret;
 142
 143         tmp = val & ~mask;
 144         old_sel = val & mask;
 145         old_sel >>= ffs(mask) - 1;
 146         delta_sel = sel - old_sel;
 147
 148         /*
 149          * If directly modify the register to change the voltage, we will face
 150          * the risk of overshoot. Put it into a multi-step, can effectively
 151          * avoid this problem, a step is 100mv here.
 152          */
 153         while (delta_sel > MAX_STEPS_ONE_TIME) {
 154                 old_sel += MAX_STEPS_ONE_TIME;
 155                 val = old_sel << (ffs(mask) - 1);
 156                 val |= tmp;
 157
 158                 /*
 159                  * i2c is 400kHz (2.5us per bit) and we must transmit _at least_
 160                  * 3 bytes (24 bits) plus start and stop so 26 bits.  So we've
 161                  * got more than 65 us between each voltage change and thus
 162                  * won't ramp faster than ~1500 uV / us.
 163                  */
 164                 ret = regmap_write(rdev->regmap, rdev->desc->vsel_reg, val);
 165                 delta_sel = sel - old_sel;
 166         }
 167
 168         sel <<= ffs(mask) - 1;
 169         val = tmp | sel;
 170         ret = regmap_write(rdev->regmap, rdev->desc->vsel_reg, val);
 171
 172         /*
 173          * When we change the voltage register directly, the ramp rate is about
 174          * 100000uv/us, wait 1us to make sure the target voltage to be stable,
 175          * so we needn't wait extra time after that.
 176          */
 177         udelay(1);
 178
 179         return ret;
 180 }
 181
 182 static int rk808_buck1_2_set_voltage_sel(struct regulator_dev *rdev,
 183                                          unsigned sel)
 184 {
 185         struct rk808_regulator_data *pdata = rdev_get_drvdata(rdev);
 186         int id = rdev->desc->id - RK808_ID_DCDC1;
 187         struct gpio_desc *gpio = pdata->dvs_gpio[id];
 188         unsigned int reg = rdev->desc->vsel_reg;
 189         unsigned old_sel;
 190         int ret, gpio_level;
 191
 192         if (!gpio)
 193                 return rk808_buck1_2_i2c_set_voltage_sel(rdev, sel);
 194
 195         gpio_level = gpiod_get_value(gpio);
 196         if (gpio_level == 0) {
 197                 reg += RK808_DVS_REG_OFFSET;
 198                 ret = regmap_read(rdev->regmap, rdev->desc->vsel_reg, &old_sel);
 199         } else {
 200                 ret = regmap_read(rdev->regmap,
 201                                   reg + RK808_DVS_REG_OFFSET,
 202                                   &old_sel);
 203         }
 204
 205         if (ret != 0)
 206                 return ret;
 207
 208         sel <<= ffs(rdev->desc->vsel_mask) - 1;
 209         sel |= old_sel & ~rdev->desc->vsel_mask;
 210
 211         ret = regmap_write(rdev->regmap, reg, sel);
 212         if (ret)
 213                 return ret;
 214
 215         gpiod_set_value(gpio, !gpio_level);
 216
 217         return ret;
 218 }
 219
 220 static int rk808_buck1_2_set_voltage_time_sel(struct regulator_dev *rdev,
 221                                        unsigned int old_selector,
 222                                        unsigned int new_selector)
 223 {
 224         struct rk808_regulator_data *pdata = rdev_get_drvdata(rdev);
 225         int id = rdev->desc->id - RK808_ID_DCDC1;
 226         struct gpio_desc *gpio = pdata->dvs_gpio[id];
 227
 228         /* if there is no dvs1/2 pin, we don't need wait extra time here. */
 229         if (!gpio)
 230                 return 0;
 231
 232         return regulator_set_voltage_time_sel(rdev, old_selector, new_selector);
 233 }
 234
 235 static int rk808_set_ramp_delay(struct regulator_dev *rdev, int ramp_delay)
 236 {
 237         unsigned int ramp_value = RK808_RAMP_RATE_10MV_PER_US;
 238         unsigned int reg = rk808_buck_config_regs[rdev->desc->id -
 239                                                   RK808_ID_DCDC1];
 240
 241         switch (ramp_delay) {
 242         case 1 ... 2000:
 243                 ramp_value = RK808_RAMP_RATE_2MV_PER_US;
 244                 break;
 245         case 2001 ... 4000:
 246                 ramp_value = RK808_RAMP_RATE_4MV_PER_US;
 247                 break;
 248         case 4001 ... 6000:
 249                 ramp_value = RK808_RAMP_RATE_6MV_PER_US;
 250                 break;
 251         case 6001 ... 10000:
 252                 break;
 253         default:
 254                 pr_warn("%s ramp_delay: %d not supported, setting 10000\n",
 255                         rdev->desc->name, ramp_delay);
 256         }
 257
 258         return regmap_update_bits(rdev->regmap, reg,
 259                                   RK808_RAMP_RATE_MASK, ramp_value);
 260 }
 261
 262 static int rk808_set_suspend_voltage(struct regulator_dev *rdev, int uv)
 263 {
 264         unsigned int reg;
 265         int sel = regulator_map_voltage_linear(rdev, uv, uv);
 266
 267         if (sel < 0)
 268                 return -EINVAL;
 269
 270         reg = rdev->desc->vsel_reg + RK808_SLP_REG_OFFSET;
 271
 272         return regmap_update_bits(rdev->regmap, reg,
 273                                   rdev->desc->vsel_mask,
 274                                   sel);
 275 }
 276
 277 static int rk808_set_suspend_voltage_range(struct regulator_dev *rdev, int uv)
 278 {
 279         unsigned int reg;
 280         int sel = regulator_map_voltage_linear_range(rdev, uv, uv);
 281
 282         if (sel < 0)
 283                 return -EINVAL;
 284
 285         reg = rdev->desc->vsel_reg + RK808_SLP_REG_OFFSET;
 286
 287         return regmap_update_bits(rdev->regmap, reg,
 288                                   rdev->desc->vsel_mask,
 289                                   sel);
 290 }
 291
 292 static int rk808_set_suspend_enable(struct regulator_dev *rdev)
 293 {
 294         unsigned int reg;
 295
 296         reg = rdev->desc->enable_reg + RK808_SLP_SET_OFF_REG_OFFSET;
 297
 298         return regmap_update_bits(rdev->regmap, reg,
 299                                   rdev->desc->enable_mask,
 300                                   0);
 301 }
 302
 303 static int rk808_set_suspend_disable(struct regulator_dev *rdev)
 304 {
 305         unsigned int reg;
 306
 307         reg = rdev->desc->enable_reg + RK808_SLP_SET_OFF_REG_OFFSET;
 308
 309         return regmap_update_bits(rdev->regmap, reg,
 310                                   rdev->desc->enable_mask,
 311                                   rdev->desc->enable_mask);
 312 }
 313
 314 static struct regulator_ops rk808_buck1_2_ops = {
 315         .list_voltage           = regulator_list_voltage_linear,
 316         .map_voltage            = regulator_map_voltage_linear,
 317         .get_voltage_sel        = rk808_buck1_2_get_voltage_sel_regmap,
 318         .set_voltage_sel        = rk808_buck1_2_set_voltage_sel,
 319         .set_voltage_time_sel   = rk808_buck1_2_set_voltage_time_sel,
 320         .enable                 = regulator_enable_regmap,
 321         .disable                = regulator_disable_regmap,
 322         .is_enabled             = regulator_is_enabled_regmap,
 323         .set_ramp_delay         = rk808_set_ramp_delay,
 324         .set_suspend_voltage    = rk808_set_suspend_voltage,
 325         .set_suspend_enable     = rk808_set_suspend_enable,
 326         .set_suspend_disable    = rk808_set_suspend_disable,
 327 };
 328
 329 static struct regulator_ops rk808_reg_ops = {
 330         .list_voltage           = regulator_list_voltage_linear,
 331         .map_voltage            = regulator_map_voltage_linear,
 332         .get_voltage_sel        = regulator_get_voltage_sel_regmap,
 333         .set_voltage_sel        = regulator_set_voltage_sel_regmap,
 334         .enable                 = regulator_enable_regmap,
 335         .disable                = regulator_disable_regmap,
 336         .is_enabled             = regulator_is_enabled_regmap,
 337         .set_suspend_voltage    = rk808_set_suspend_voltage,
 338         .set_suspend_enable     = rk808_set_suspend_enable,
 339         .set_suspend_disable    = rk808_set_suspend_disable,
 340 };
 341
 342 static struct regulator_ops rk808_reg_ops_ranges = {
 343         .list_voltage           = regulator_list_voltage_linear_range,
 344         .map_voltage            = regulator_map_voltage_linear_range,
 345         .get_voltage_sel        = regulator_get_voltage_sel_regmap,
 346         .set_voltage_sel        = regulator_set_voltage_sel_regmap,
 347         .enable                 = regulator_enable_regmap,
 348         .disable                = regulator_disable_regmap,
 349         .is_enabled             = regulator_is_enabled_regmap,
 350         .set_suspend_voltage    = rk808_set_suspend_voltage_range,
 351         .set_suspend_enable     = rk808_set_suspend_enable,
 352         .set_suspend_disable    = rk808_set_suspend_disable,
 353 };
 354
 355 static struct regulator_ops rk808_switch_ops = {
 356         .enable                 = regulator_enable_regmap,
 357         .disable                = regulator_disable_regmap,
 358         .is_enabled             = regulator_is_enabled_regmap,
 359         .set_suspend_enable     = rk808_set_suspend_enable,
 360         .set_suspend_disable    = rk808_set_suspend_disable,
 361 };
 362
 363 static const struct regulator_desc rk808_reg[] = {
 364         {
 365                 .name = "DCDC_REG1",
 366                 .supply_name = "vcc1",
 367                 .of_match = of_match_ptr("DCDC_REG1"),
 368                 .regulators_node = of_match_ptr("regulators"),
 369                 .id = RK808_ID_DCDC1,
 370                 .ops = &rk808_buck1_2_ops,
 371                 .type = REGULATOR_VOLTAGE,
 372                 .min_uV = 712500,
 373                 .uV_step = 12500,
 374                 .n_voltages = 64,
 375                 .vsel_reg = RK808_BUCK1_ON_VSEL_REG,
 376                 .vsel_mask = RK808_BUCK_VSEL_MASK,
 377                 .enable_reg = RK808_DCDC_EN_REG,
 378                 .enable_mask = BIT(0),
 379                 .owner = THIS_MODULE,
 380         }, {
 381                 .name = "DCDC_REG2",
 382                 .supply_name = "vcc2",
 383                 .of_match = of_match_ptr("DCDC_REG2"),
 384                 .regulators_node = of_match_ptr("regulators"),
 385                 .id = RK808_ID_DCDC2,
 386                 .ops = &rk808_buck1_2_ops,
 387                 .type = REGULATOR_VOLTAGE,
 388                 .min_uV = 712500,
 389                 .uV_step = 12500,
 390                 .n_voltages = 64,
 391                 .vsel_reg = RK808_BUCK2_ON_VSEL_REG,
 392                 .vsel_mask = RK808_BUCK_VSEL_MASK,
 393                 .enable_reg = RK808_DCDC_EN_REG,
 394                 .enable_mask = BIT(1),
 395                 .owner = THIS_MODULE,
 396         }, {
 397                 .name = "DCDC_REG3",
 398                 .supply_name = "vcc3",
 399                 .of_match = of_match_ptr("DCDC_REG3"),
 400                 .regulators_node = of_match_ptr("regulators"),
 401                 .id = RK808_ID_DCDC3,
 402                 .ops = &rk808_switch_ops,
 403                 .type = REGULATOR_VOLTAGE,
 404                 .n_voltages = 1,
 405                 .enable_reg = RK808_DCDC_EN_REG,
 406                 .enable_mask = BIT(2),
 407                 .owner = THIS_MODULE,
 408         },
 409         RK8XX_DESC(RK808_ID_DCDC4, "DCDC_REG4", "vcc4", 1800, 3300, 100,
 410                 RK808_BUCK4_ON_VSEL_REG, RK808_BUCK4_VSEL_MASK,
 411                 RK808_DCDC_EN_REG, BIT(3), 0),
 412         RK8XX_DESC(RK808_ID_LDO1, "LDO_REG1", "vcc6", 1800, 3400, 100,
 413                 RK808_LDO1_ON_VSEL_REG, RK808_LDO_VSEL_MASK, RK808_LDO_EN_REG,
 414                 BIT(0), 400),
 415         RK8XX_DESC(RK808_ID_LDO2, "LDO_REG2", "vcc6", 1800, 3400, 100,
 416                 RK808_LDO2_ON_VSEL_REG, RK808_LDO_VSEL_MASK, RK808_LDO_EN_REG,
 417                 BIT(1), 400),
 418         {
 419                 .name = "LDO_REG3",
 420                 .supply_name = "vcc7",
 421                 .of_match = of_match_ptr("LDO_REG3"),
 422                 .regulators_node = of_match_ptr("regulators"),
 423                 .id = RK808_ID_LDO3,
 424                 .ops = &rk808_reg_ops_ranges,
 425                 .type = REGULATOR_VOLTAGE,
 426                 .n_voltages = 16,
 427                 .linear_ranges = rk808_ldo3_voltage_ranges,
 428                 .n_linear_ranges = ARRAY_SIZE(rk808_ldo3_voltage_ranges),
 429                 .vsel_reg = RK808_LDO3_ON_VSEL_REG,
 430                 .vsel_mask = RK808_BUCK4_VSEL_MASK,
 431                 .enable_reg = RK808_LDO_EN_REG,
 432                 .enable_mask = BIT(2),
 433                 .enable_time = 400,
 434                 .owner = THIS_MODULE,
 435         },
 436         RK8XX_DESC(RK808_ID_LDO4, "LDO_REG4", "vcc9", 1800, 3400, 100,
 437                 RK808_LDO4_ON_VSEL_REG, RK808_LDO_VSEL_MASK, RK808_LDO_EN_REG,
 438                 BIT(3), 400),
 439         RK8XX_DESC(RK808_ID_LDO5, "LDO_REG5", "vcc9", 1800, 3400, 100,
 440                 RK808_LDO5_ON_VSEL_REG, RK808_LDO_VSEL_MASK, RK808_LDO_EN_REG,
 441                 BIT(4), 400),
 442         RK8XX_DESC(RK808_ID_LDO6, "LDO_REG6", "vcc10", 800, 2500, 100,
 443                 RK808_LDO6_ON_VSEL_REG, RK808_LDO_VSEL_MASK, RK808_LDO_EN_REG,
 444                 BIT(5), 400),
 445         RK8XX_DESC(RK808_ID_LDO7, "LDO_REG7", "vcc7", 800, 2500, 100,
 446                 RK808_LDO7_ON_VSEL_REG, RK808_LDO_VSEL_MASK, RK808_LDO_EN_REG,
 447                 BIT(6), 400),
 448         RK8XX_DESC(RK808_ID_LDO8, "LDO_REG8", "vcc11", 1800, 3400, 100,
 449                 RK808_LDO8_ON_VSEL_REG, RK808_LDO_VSEL_MASK, RK808_LDO_EN_REG,
 450                 BIT(7), 400),
 451         RK8XX_DESC_SWITCH(RK808_ID_SWITCH1, "SWITCH_REG1", "vcc8",
 452                 RK808_DCDC_EN_REG, BIT(5)),
 453         RK8XX_DESC_SWITCH(RK808_ID_SWITCH2, "SWITCH_REG2", "vcc12",
 454                 RK808_DCDC_EN_REG, BIT(6)),
 455 };
 456
 457 static int rk808_regulator_dt_parse_pdata(struct device *dev,
 458                                    struct device *client_dev,
 459                                    struct regmap *map,
 460                                    struct rk808_regulator_data *pdata)
 461 {
 462         struct device_node *np;
 463         int tmp, ret = 0, i;
 464
 465         np = of_get_child_by_name(client_dev->of_node, "regulators");
 466         if (!np)
 467                 return -ENXIO;
 468
 469         for (i = 0; i < ARRAY_SIZE(pdata->dvs_gpio); i++) {
 470                 pdata->dvs_gpio[i] =
 471                         devm_gpiod_get_index_optional(client_dev, "dvs", i,
 472                                                       GPIOD_OUT_LOW);
 473                 if (IS_ERR(pdata->dvs_gpio[i])) {
 474                         ret = PTR_ERR(pdata->dvs_gpio[i]);
 475                         dev_err(dev, "failed to get dvs%d gpio (%d)\n", i, ret);
 476                         goto dt_parse_end;
 477                 }
 478
 479                 if (!pdata->dvs_gpio[i]) {
 480                         dev_warn(dev, "there is no dvs%d gpio\n", i);
 481                         continue;
 482                 }
 483
 484                 tmp = i ? RK808_DVS2_POL : RK808_DVS1_POL;
 485                 ret = regmap_update_bits(map, RK808_IO_POL_REG, tmp,
 486                                 gpiod_is_active_low(pdata->dvs_gpio[i]) ?
 487                                 0 : tmp);
 488         }
 489
 490 dt_parse_end:
 491         of_node_put(np);
 492         return ret;
 493 }
 494
 495 static int rk808_regulator_probe(struct platform_device *pdev)
 496 {
 497         struct rk808 *rk808 = dev_get_drvdata(pdev->dev.parent);
 498         struct i2c_client *client = rk808->i2c;
 499         struct regulator_config config = {};
 500         struct regulator_dev *rk808_rdev;
 501         struct rk808_regulator_data *pdata;
 502         int ret, i;
 503
 504         pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
 505         if (!pdata)
 506                 return -ENOMEM;
 507
 508         ret = rk808_regulator_dt_parse_pdata(&pdev->dev, &client->dev,
 509                                              rk808->regmap, pdata);
 510         if (ret < 0)
 511                 return ret;
 512
 513         platform_set_drvdata(pdev, pdata);
 514
 515         config.dev = &client->dev;
 516         config.driver_data = pdata;
 517         config.regmap = rk808->regmap;
 518
 519         /* Instantiate the regulators */
 520         for (i = 0; i < RK808_NUM_REGULATORS; i++) {
 521                 rk808_rdev = devm_regulator_register(&pdev->dev,
 522                                                      &rk808_reg[i], &config);
 523                 if (IS_ERR(rk808_rdev)) {
 524                         dev_err(&client->dev,
 525                                 "failed to register %d regulator\n", i);
 526                         return PTR_ERR(rk808_rdev);
 527                 }
 528         }
 529
 530         return 0;
 531 }
 532
 533 static struct platform_driver rk808_regulator_driver = {
 534         .probe = rk808_regulator_probe,
 535         .driver = {
 536                 .name = "rk808-regulator"
 537         },
 538 };
 539
 540 module_platform_driver(rk808_regulator_driver);
 541
 542 MODULE_DESCRIPTION("regulator driver for the rk808 series PMICs");
 543 MODULE_AUTHOR("Chris Zhong<zyw@rock-chips.com>");
 544 MODULE_AUTHOR("Zhang Qing<zhangqing@rock-chips.com>");
 545 MODULE_LICENSE("GPL");
 546 MODULE_ALIAS("platform:rk808-regulator");