linux/drivers/regulator/max14577.c
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   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 */
  30struct 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 */
  45static 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
  61static 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
  82static 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
 103static 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
 150static 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
 157static 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
 165static 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
 188static 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
 199static 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
 251static struct of_regulator_match max14577_regulator_matches[] = {
 252        { .name = "SAFEOUT", },
 253        { .name = "CHARGER", },
 254};
 255
 256static struct of_regulator_match max77836_regulator_matches[] = {
 257        { .name = "SAFEOUT", },
 258        { .name = "CHARGER", },
 259        { .name = "LDO1", },
 260        { .name = "LDO2", },
 261};
 262
 263static 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
 300static 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
 313static 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 */
 326static int max14577_regulator_dt_parse_pdata(struct platform_device *pdev,
 327                enum maxim_device_type dev_type)
 328{
 329        return 0;
 330}
 331static inline struct regulator_init_data *match_init_data(int index,
 332                enum maxim_device_type dev_type)
 333{
 334        return NULL;
 335}
 336
 337static 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 */
 350static 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
 369static 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
 427static const struct platform_device_id max14577_regulator_id[] = {
 428        { "max14577-regulator", MAXIM_DEVICE_TYPE_MAX14577, },
 429        { "max77836-regulator", MAXIM_DEVICE_TYPE_MAX77836, },
 430        { }
 431};
 432MODULE_DEVICE_TABLE(platform, max14577_regulator_id);
 433
 434static 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
 443static 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}
 465subsys_initcall(max14577_regulator_init);
 466
 467static void __exit max14577_regulator_exit(void)
 468{
 469        platform_driver_unregister(&max14577_regulator_driver);
 470}
 471module_exit(max14577_regulator_exit);
 472
 473MODULE_AUTHOR("Krzysztof Kozlowski <k.kozlowski@samsung.com>");
 474MODULE_DESCRIPTION("Maxim 14577/77836 regulator driver");
 475MODULE_LICENSE("GPL");
 476MODULE_ALIAS("platform:max14577-regulator");
 477
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