drivers/regulator/max14577.c

   1 /*
   2  * max14577.c - Regulator driver for the Maxim 14577/77836
   3  *
   4  * Copyright (C) 2013,2014 Samsung Electronics
   5  * Krzysztof Kozlowski <k.kozlowski@samsung.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  */
  17
  18 #include <linux/module.h>
  19 #include <linux/platform_device.h>
  20 #include <linux/regulator/driver.h>
  21 #include <linux/mfd/max14577.h>
  22 #include <linux/mfd/max14577-private.h>
  23 #include <linux/regulator/of_regulator.h>
  24
  25 /*
  26  * Valid limits of current for max14577 and max77836 chargers.
  27  * They must correspond to MBCICHWRCL and MBCICHWRCH fields in CHGCTRL4
  28  * register for given chipset.
  29  */
  30 struct maxim_charger_current {
  31         /* Minimal current, set in CHGCTRL4/MBCICHWRCL, uA */
  32         unsigned int min;
  33         /*
  34          * Minimal current when high setting is active,
  35          * set in CHGCTRL4/MBCICHWRCH, uA
  36          */
  37         unsigned int high_start;
  38         /* Value of one step in high setting, uA */
  39         unsigned int high_step;
  40         /* Maximum current of high setting, uA */
  41         unsigned int max;
  42 };
  43
  44 /* Table of valid charger currents for different Maxim chipsets */
  45 static const struct maxim_charger_current maxim_charger_currents[] = {
  46         [MAXIM_DEVICE_TYPE_UNKNOWN] = { 0, 0, 0, 0 },
  47         [MAXIM_DEVICE_TYPE_MAX14577] = {
  48                 .min            = MAX14577_REGULATOR_CURRENT_LIMIT_MIN,
  49                 .high_start     = MAX14577_REGULATOR_CURRENT_LIMIT_HIGH_START,
  50                 .high_step      = MAX14577_REGULATOR_CURRENT_LIMIT_HIGH_STEP,
  51                 .max            = MAX14577_REGULATOR_CURRENT_LIMIT_MAX,
  52         },
  53         [MAXIM_DEVICE_TYPE_MAX77836] = {
  54                 .min            = MAX77836_REGULATOR_CURRENT_LIMIT_MIN,
  55                 .high_start     = MAX77836_REGULATOR_CURRENT_LIMIT_HIGH_START,
  56                 .high_step      = MAX77836_REGULATOR_CURRENT_LIMIT_HIGH_STEP,
  57                 .max            = MAX77836_REGULATOR_CURRENT_LIMIT_MAX,
  58         },
  59 };
  60
  61 static int max14577_reg_is_enabled(struct regulator_dev *rdev)
  62 {
  63         int rid = rdev_get_id(rdev);
  64         struct regmap *rmap = rdev->regmap;
  65         u8 reg_data;
  66
  67         switch (rid) {
  68         case MAX14577_CHARGER:
  69                 max14577_read_reg(rmap, MAX14577_CHG_REG_CHG_CTRL2, &reg_data);
  70                 if ((reg_data & CHGCTRL2_MBCHOSTEN_MASK) == 0)
  71                         return 0;
  72                 max14577_read_reg(rmap, MAX14577_CHG_REG_STATUS3, &reg_data);
  73                 if ((reg_data & STATUS3_CGMBC_MASK) == 0)
  74                         return 0;
  75                 /* MBCHOSTEN and CGMBC are on */
  76                 return 1;
  77         default:
  78                 return -EINVAL;
  79         }
  80 }
  81
  82 static int max14577_reg_get_current_limit(struct regulator_dev *rdev)
  83 {
  84         u8 reg_data;
  85         struct regmap *rmap = rdev->regmap;
  86         struct max14577 *max14577 = rdev_get_drvdata(rdev);
  87         const struct maxim_charger_current *limits =
  88                 &maxim_charger_currents[max14577->dev_type];
  89
  90         if (rdev_get_id(rdev) != MAX14577_CHARGER)
  91                 return -EINVAL;
  92
  93         max14577_read_reg(rmap, MAX14577_CHG_REG_CHG_CTRL4, &reg_data);
  94
  95         if ((reg_data & CHGCTRL4_MBCICHWRCL_MASK) == 0)
  96                 return limits->min;
  97
  98         reg_data = ((reg_data & CHGCTRL4_MBCICHWRCH_MASK) >>
  99                         CHGCTRL4_MBCICHWRCH_SHIFT);
 100         return limits->high_start + reg_data * limits->high_step;
 101 }
 102
 103 static int max14577_reg_set_current_limit(struct regulator_dev *rdev,
 104                 int min_uA, int max_uA)
 105 {
 106         int i, current_bits = 0xf;
 107         u8 reg_data;
 108         struct max14577 *max14577 = rdev_get_drvdata(rdev);
 109         const struct maxim_charger_current *limits =
 110                 &maxim_charger_currents[max14577->dev_type];
 111
 112         if (rdev_get_id(rdev) != MAX14577_CHARGER)
 113                 return -EINVAL;
 114
 115         if (min_uA > limits->max || max_uA < limits->min)
 116                 return -EINVAL;
 117
 118         if (max_uA < limits->high_start) {
 119                 /*
 120                  * Less than high_start,
 121                  * so set the minimal current (turn only Low Bit off)
 122                  */
 123                 u8 reg_data = 0x0 << CHGCTRL4_MBCICHWRCL_SHIFT;
 124                 return max14577_update_reg(rdev->regmap,
 125                                 MAX14577_CHG_REG_CHG_CTRL4,
 126                                 CHGCTRL4_MBCICHWRCL_MASK, reg_data);
 127         }
 128
 129         /*
 130          * max_uA is in range: <high_start, inifinite>, so search for
 131          * valid current starting from maximum current.
 132          */
 133         for (i = limits->max; i >= limits->high_start; i -= limits->high_step) {
 134                 if (i <= max_uA)
 135                         break;
 136                 current_bits--;
 137         }
 138         BUG_ON(current_bits < 0); /* Cannot happen */
 139
 140         /* Turn Low Bit on (use range high_start-max)... */
 141         reg_data = 0x1 << CHGCTRL4_MBCICHWRCL_SHIFT;
 142         /* and set proper High Bits */
 143         reg_data |= current_bits << CHGCTRL4_MBCICHWRCH_SHIFT;
 144
 145         return max14577_update_reg(rdev->regmap, MAX14577_CHG_REG_CHG_CTRL4,
 146                         CHGCTRL4_MBCICHWRCL_MASK | CHGCTRL4_MBCICHWRCH_MASK,
 147                         reg_data);
 148 }
 149
 150 static struct regulator_ops max14577_safeout_ops = {
 151         .is_enabled             = regulator_is_enabled_regmap,
 152         .enable                 = regulator_enable_regmap,
 153         .disable                = regulator_disable_regmap,
 154         .list_voltage           = regulator_list_voltage_linear,
 155 };
 156
 157 static struct regulator_ops max14577_charger_ops = {
 158         .is_enabled             = max14577_reg_is_enabled,
 159         .enable                 = regulator_enable_regmap,
 160         .disable                = regulator_disable_regmap,
 161         .get_current_limit      = max14577_reg_get_current_limit,
 162         .set_current_limit      = max14577_reg_set_current_limit,
 163 };
 164
 165 static const struct regulator_desc max14577_supported_regulators[] = {
 166         [MAX14577_SAFEOUT] = {
 167                 .name           = "SAFEOUT",
 168                 .id             = MAX14577_SAFEOUT,
 169                 .ops            = &max14577_safeout_ops,
 170                 .type           = REGULATOR_VOLTAGE,
 171                 .owner          = THIS_MODULE,
 172                 .n_voltages     = 1,
 173                 .min_uV         = MAX14577_REGULATOR_SAFEOUT_VOLTAGE,
 174                 .enable_reg     = MAX14577_REG_CONTROL2,
 175                 .enable_mask    = CTRL2_SFOUTORD_MASK,
 176         },
 177         [MAX14577_CHARGER] = {
 178                 .name           = "CHARGER",
 179                 .id             = MAX14577_CHARGER,
 180                 .ops            = &max14577_charger_ops,
 181                 .type           = REGULATOR_CURRENT,
 182                 .owner          = THIS_MODULE,
 183                 .enable_reg     = MAX14577_CHG_REG_CHG_CTRL2,
 184                 .enable_mask    = CHGCTRL2_MBCHOSTEN_MASK,
 185         },
 186 };
 187
 188 static struct regulator_ops max77836_ldo_ops = {
 189         .is_enabled             = regulator_is_enabled_regmap,
 190         .enable                 = regulator_enable_regmap,
 191         .disable                = regulator_disable_regmap,
 192         .list_voltage           = regulator_list_voltage_linear,
 193         .map_voltage            = regulator_map_voltage_linear,
 194         .get_voltage_sel        = regulator_get_voltage_sel_regmap,
 195         .set_voltage_sel        = regulator_set_voltage_sel_regmap,
 196         /* TODO: add .set_suspend_mode */
 197 };
 198
 199 static const struct regulator_desc max77836_supported_regulators[] = {
 200         [MAX14577_SAFEOUT] = {
 201                 .name           = "SAFEOUT",
 202                 .id             = MAX14577_SAFEOUT,
 203                 .ops            = &max14577_safeout_ops,
 204                 .type           = REGULATOR_VOLTAGE,
 205                 .owner          = THIS_MODULE,
 206                 .n_voltages     = 1,
 207                 .min_uV         = MAX14577_REGULATOR_SAFEOUT_VOLTAGE,
 208                 .enable_reg     = MAX14577_REG_CONTROL2,
 209                 .enable_mask    = CTRL2_SFOUTORD_MASK,
 210         },
 211         [MAX14577_CHARGER] = {
 212                 .name           = "CHARGER",
 213                 .id             = MAX14577_CHARGER,
 214                 .ops            = &max14577_charger_ops,
 215                 .type           = REGULATOR_CURRENT,
 216                 .owner          = THIS_MODULE,
 217                 .enable_reg     = MAX14577_CHG_REG_CHG_CTRL2,
 218                 .enable_mask    = CHGCTRL2_MBCHOSTEN_MASK,
 219         },
 220         [MAX77836_LDO1] = {
 221                 .name           = "LDO1",
 222                 .id             = MAX77836_LDO1,
 223                 .ops            = &max77836_ldo_ops,
 224                 .type           = REGULATOR_VOLTAGE,
 225                 .owner          = THIS_MODULE,
 226                 .n_voltages     = MAX77836_REGULATOR_LDO_VOLTAGE_STEPS_NUM,
 227                 .min_uV         = MAX77836_REGULATOR_LDO_VOLTAGE_MIN,
 228                 .uV_step        = MAX77836_REGULATOR_LDO_VOLTAGE_STEP,
 229                 .enable_reg     = MAX77836_LDO_REG_CNFG1_LDO1,
 230                 .enable_mask    = MAX77836_CNFG1_LDO_PWRMD_MASK,
 231                 .vsel_reg       = MAX77836_LDO_REG_CNFG1_LDO1,
 232                 .vsel_mask      = MAX77836_CNFG1_LDO_TV_MASK,
 233         },
 234         [MAX77836_LDO2] = {
 235                 .name           = "LDO2",
 236                 .id             = MAX77836_LDO2,
 237                 .ops            = &max77836_ldo_ops,
 238                 .type           = REGULATOR_VOLTAGE,
 239                 .owner          = THIS_MODULE,
 240                 .n_voltages     = MAX77836_REGULATOR_LDO_VOLTAGE_STEPS_NUM,
 241                 .min_uV         = MAX77836_REGULATOR_LDO_VOLTAGE_MIN,
 242                 .uV_step        = MAX77836_REGULATOR_LDO_VOLTAGE_STEP,
 243                 .enable_reg     = MAX77836_LDO_REG_CNFG1_LDO2,
 244                 .enable_mask    = MAX77836_CNFG1_LDO_PWRMD_MASK,
 245                 .vsel_reg       = MAX77836_LDO_REG_CNFG1_LDO2,
 246                 .vsel_mask      = MAX77836_CNFG1_LDO_TV_MASK,
 247         },
 248 };
 249
 250 #ifdef CONFIG_OF
 251 static struct of_regulator_match max14577_regulator_matches[] = {
 252         { .name = "SAFEOUT", },
 253         { .name = "CHARGER", },
 254 };
 255
 256 static struct of_regulator_match max77836_regulator_matches[] = {
 257         { .name = "SAFEOUT", },
 258         { .name = "CHARGER", },
 259         { .name = "LDO1", },
 260         { .name = "LDO2", },
 261 };
 262
 263 static int max14577_regulator_dt_parse_pdata(struct platform_device *pdev,
 264                 enum maxim_device_type dev_type)
 265 {
 266         int ret;
 267         struct device_node *np;
 268         struct of_regulator_match *regulator_matches;
 269         unsigned int regulator_matches_size;
 270
 271         np = of_get_child_by_name(pdev->dev.parent->of_node, "regulators");
 272         if (!np) {
 273                 dev_err(&pdev->dev, "Failed to get child OF node for regulators\n");
 274                 return -EINVAL;
 275         }
 276
 277         switch (dev_type) {
 278         case MAXIM_DEVICE_TYPE_MAX77836:
 279                 regulator_matches = max77836_regulator_matches;
 280                 regulator_matches_size = ARRAY_SIZE(max77836_regulator_matches);
 281                 break;
 282         case MAXIM_DEVICE_TYPE_MAX14577:
 283         default:
 284                 regulator_matches = max14577_regulator_matches;
 285                 regulator_matches_size = ARRAY_SIZE(max14577_regulator_matches);
 286         }
 287
 288         ret = of_regulator_match(&pdev->dev, np, regulator_matches,
 289                         regulator_matches_size);
 290         if (ret < 0)
 291                 dev_err(&pdev->dev, "Error parsing regulator init data: %d\n", ret);
 292         else
 293                 ret = 0;
 294
 295         of_node_put(np);
 296
 297         return ret;
 298 }
 299
 300 static inline struct regulator_init_data *match_init_data(int index,
 301                 enum maxim_device_type dev_type)
 302 {
 303         switch (dev_type) {
 304         case MAXIM_DEVICE_TYPE_MAX77836:
 305                 return max77836_regulator_matches[index].init_data;
 306
 307         case MAXIM_DEVICE_TYPE_MAX14577:
 308         default:
 309                 return max14577_regulator_matches[index].init_data;
 310         }
 311 }
 312
 313 static inline struct device_node *match_of_node(int index,
 314                 enum maxim_device_type dev_type)
 315 {
 316         switch (dev_type) {
 317         case MAXIM_DEVICE_TYPE_MAX77836:
 318                 return max77836_regulator_matches[index].of_node;
 319
 320         case MAXIM_DEVICE_TYPE_MAX14577:
 321         default:
 322                 return max14577_regulator_matches[index].of_node;
 323         }
 324 }
 325 #else /* CONFIG_OF */
 326 static int max14577_regulator_dt_parse_pdata(struct platform_device *pdev,
 327                 enum maxim_device_type dev_type)
 328 {
 329         return 0;
 330 }
 331 static inline struct regulator_init_data *match_init_data(int index,
 332                 enum maxim_device_type dev_type)
 333 {
 334         return NULL;
 335 }
 336
 337 static inline struct device_node *match_of_node(int index,
 338                 enum maxim_device_type dev_type)
 339 {
 340         return NULL;
 341 }
 342 #endif /* CONFIG_OF */
 343
 344 /**
 345  * Registers for regulators of max77836 use different I2C slave addresses so
 346  * different regmaps must be used for them.
 347  *
 348  * Returns proper regmap for accessing regulator passed by id.
 349  */
 350 static struct regmap *max14577_get_regmap(struct max14577 *max14577,
 351                 int reg_id)
 352 {
 353         switch (max14577->dev_type) {
 354         case MAXIM_DEVICE_TYPE_MAX77836:
 355                 switch (reg_id) {
 356                 case MAX77836_SAFEOUT ... MAX77836_CHARGER:
 357                         return max14577->regmap;
 358                 default:
 359                         /* MAX77836_LDO1 ... MAX77836_LDO2 */
 360                         return max14577->regmap_pmic;
 361                 }
 362
 363         case MAXIM_DEVICE_TYPE_MAX14577:
 364         default:
 365                 return max14577->regmap;
 366         }
 367 }
 368
 369 static int max14577_regulator_probe(struct platform_device *pdev)
 370 {
 371         struct max14577 *max14577 = dev_get_drvdata(pdev->dev.parent);
 372         struct max14577_platform_data *pdata = dev_get_platdata(max14577->dev);
 373         int i, ret;
 374         struct regulator_config config = {};
 375         const struct regulator_desc *supported_regulators;
 376         unsigned int supported_regulators_size;
 377         enum maxim_device_type dev_type = max14577->dev_type;
 378
 379         ret = max14577_regulator_dt_parse_pdata(pdev, dev_type);
 380         if (ret)
 381                 return ret;
 382
 383         switch (dev_type) {
 384         case MAXIM_DEVICE_TYPE_MAX77836:
 385                 supported_regulators = max77836_supported_regulators;
 386                 supported_regulators_size = ARRAY_SIZE(max77836_supported_regulators);
 387                 break;
 388         case MAXIM_DEVICE_TYPE_MAX14577:
 389         default:
 390                 supported_regulators = max14577_supported_regulators;
 391                 supported_regulators_size = ARRAY_SIZE(max14577_supported_regulators);
 392         }
 393
 394         config.dev = &pdev->dev;
 395         config.driver_data = max14577;
 396
 397         for (i = 0; i < supported_regulators_size; i++) {
 398                 struct regulator_dev *regulator;
 399                 /*
 400                  * Index of supported_regulators[] is also the id and must
 401                  * match index of pdata->regulators[].
 402                  */
 403                 if (pdata && pdata->regulators) {
 404                         config.init_data = pdata->regulators[i].initdata;
 405                         config.of_node = pdata->regulators[i].of_node;
 406                 } else {
 407                         config.init_data = match_init_data(i, dev_type);
 408                         config.of_node = match_of_node(i, dev_type);
 409                 }
 410                 config.regmap = max14577_get_regmap(max14577,
 411                                 supported_regulators[i].id);
 412
 413                 regulator = devm_regulator_register(&pdev->dev,
 414                                 &supported_regulators[i], &config);
 415                 if (IS_ERR(regulator)) {
 416                         ret = PTR_ERR(regulator);
 417                         dev_err(&pdev->dev,
 418                                         "Regulator init failed for %d/%s with error: %d\n",
 419                                         i, supported_regulators[i].name, ret);
 420                         return ret;
 421                 }
 422         }
 423
 424         return ret;
 425 }
 426
 427 static const struct platform_device_id max14577_regulator_id[] = {
 428         { "max14577-regulator", MAXIM_DEVICE_TYPE_MAX14577, },
 429         { "max77836-regulator", MAXIM_DEVICE_TYPE_MAX77836, },
 430         { }
 431 };
 432 MODULE_DEVICE_TABLE(platform, max14577_regulator_id);
 433
 434 static struct platform_driver max14577_regulator_driver = {
 435         .driver = {
 436                    .owner = THIS_MODULE,
 437                    .name = "max14577-regulator",
 438                    },
 439         .probe          = max14577_regulator_probe,
 440         .id_table       = max14577_regulator_id,
 441 };
 442
 443 static int __init max14577_regulator_init(void)
 444 {
 445         /* Check for valid values for charger */
 446         BUILD_BUG_ON(MAX14577_REGULATOR_CURRENT_LIMIT_HIGH_START +
 447                         MAX14577_REGULATOR_CURRENT_LIMIT_HIGH_STEP * 0xf !=
 448                         MAX14577_REGULATOR_CURRENT_LIMIT_MAX);
 449         BUILD_BUG_ON(MAX77836_REGULATOR_CURRENT_LIMIT_HIGH_START +
 450                         MAX77836_REGULATOR_CURRENT_LIMIT_HIGH_STEP * 0xf !=
 451                         MAX77836_REGULATOR_CURRENT_LIMIT_MAX);
 452         /* Valid charger current values must be provided for each chipset */
 453         BUILD_BUG_ON(ARRAY_SIZE(maxim_charger_currents) != MAXIM_DEVICE_TYPE_NUM);
 454
 455         BUILD_BUG_ON(ARRAY_SIZE(max14577_supported_regulators) != MAX14577_REGULATOR_NUM);
 456         BUILD_BUG_ON(ARRAY_SIZE(max77836_supported_regulators) != MAX77836_REGULATOR_NUM);
 457
 458         BUILD_BUG_ON(MAX77836_REGULATOR_LDO_VOLTAGE_MIN +
 459                         (MAX77836_REGULATOR_LDO_VOLTAGE_STEP *
 460                           (MAX77836_REGULATOR_LDO_VOLTAGE_STEPS_NUM - 1)) !=
 461                         MAX77836_REGULATOR_LDO_VOLTAGE_MAX);
 462
 463         return platform_driver_register(&max14577_regulator_driver);
 464 }
 465 subsys_initcall(max14577_regulator_init);
 466
 467 static void __exit max14577_regulator_exit(void)
 468 {
 469         platform_driver_unregister(&max14577_regulator_driver);
 470 }
 471 module_exit(max14577_regulator_exit);
 472
 473 MODULE_AUTHOR("Krzysztof Kozlowski <k.kozlowski@samsung.com>");
 474 MODULE_DESCRIPTION("Maxim 14577/77836 regulator driver");
 475 MODULE_LICENSE("GPL");
 476 MODULE_ALIAS("platform:max14577-regulator");