linux/drivers/regulator/ti-abb-regulator.c
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   1/*
   2 * Texas Instruments SoC Adaptive Body Bias(ABB) Regulator
   3 *
   4 * Copyright (C) 2011 Texas Instruments, Inc.
   5 * Mike Turquette <mturquette@ti.com>
   6 *
   7 * Copyright (C) 2012-2013 Texas Instruments, Inc.
   8 * Andrii Tseglytskyi <andrii.tseglytskyi@ti.com>
   9 * Nishanth Menon <nm@ti.com>
  10 *
  11 * This program is free software; you can redistribute it and/or modify
  12 * it under the terms of the GNU General Public License version 2 as
  13 * published by the Free Software Foundation.
  14 *
  15 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
  16 * kind, whether express or implied; without even the implied warranty
  17 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 * GNU General Public License for more details.
  19 */
  20#include <linux/clk.h>
  21#include <linux/delay.h>
  22#include <linux/err.h>
  23#include <linux/io.h>
  24#include <linux/module.h>
  25#include <linux/of_device.h>
  26#include <linux/of.h>
  27#include <linux/platform_device.h>
  28#include <linux/regulator/driver.h>
  29#include <linux/regulator/machine.h>
  30#include <linux/regulator/of_regulator.h>
  31
  32/*
  33 * ABB LDO operating states:
  34 * NOMINAL_OPP: bypasses the ABB LDO
  35 * FAST_OPP:    sets ABB LDO to Forward Body-Bias
  36 * SLOW_OPP:    sets ABB LDO to Reverse Body-Bias
  37 */
  38#define TI_ABB_NOMINAL_OPP      0
  39#define TI_ABB_FAST_OPP         1
  40#define TI_ABB_SLOW_OPP         3
  41
  42/**
  43 * struct ti_abb_info - ABB information per voltage setting
  44 * @opp_sel:    one of TI_ABB macro
  45 * @vset:       (optional) vset value that LDOVBB needs to be overriden with.
  46 *
  47 * Array of per voltage entries organized in the same order as regulator_desc's
  48 * volt_table list. (selector is used to index from this array)
  49 */
  50struct ti_abb_info {
  51        u32 opp_sel;
  52        u32 vset;
  53};
  54
  55/**
  56 * struct ti_abb_reg - Register description for ABB block
  57 * @setup_reg:                  setup register offset from base
  58 * @control_reg:                control register offset from base
  59 * @sr2_wtcnt_value_mask:       setup register- sr2_wtcnt_value mask
  60 * @fbb_sel_mask:               setup register- FBB sel mask
  61 * @rbb_sel_mask:               setup register- RBB sel mask
  62 * @sr2_en_mask:                setup register- enable mask
  63 * @opp_change_mask:            control register - mask to trigger LDOVBB change
  64 * @opp_sel_mask:               control register - mask for mode to operate
  65 */
  66struct ti_abb_reg {
  67        u32 setup_reg;
  68        u32 control_reg;
  69
  70        /* Setup register fields */
  71        u32 sr2_wtcnt_value_mask;
  72        u32 fbb_sel_mask;
  73        u32 rbb_sel_mask;
  74        u32 sr2_en_mask;
  75
  76        /* Control register fields */
  77        u32 opp_change_mask;
  78        u32 opp_sel_mask;
  79};
  80
  81/**
  82 * struct ti_abb - ABB instance data
  83 * @rdesc:                      regulator descriptor
  84 * @clk:                        clock(usually sysclk) supplying ABB block
  85 * @base:                       base address of ABB block
  86 * @int_base:                   interrupt register base address
  87 * @efuse_base:                 (optional) efuse base address for ABB modes
  88 * @ldo_base:                   (optional) LDOVBB vset override base address
  89 * @regs:                       pointer to struct ti_abb_reg for ABB block
  90 * @txdone_mask:                mask on int_base for tranxdone interrupt
  91 * @ldovbb_override_mask:       mask to ldo_base for overriding default LDO VBB
  92 *                              vset with value from efuse
  93 * @ldovbb_vset_mask:           mask to ldo_base for providing the VSET override
  94 * @info:                       array to per voltage ABB configuration
  95 * @current_info_idx:           current index to info
  96 * @settling_time:              SoC specific settling time for LDO VBB
  97 */
  98struct ti_abb {
  99        struct regulator_desc rdesc;
 100        struct clk *clk;
 101        void __iomem *base;
 102        void __iomem *int_base;
 103        void __iomem *efuse_base;
 104        void __iomem *ldo_base;
 105
 106        const struct ti_abb_reg *regs;
 107        u32 txdone_mask;
 108        u32 ldovbb_override_mask;
 109        u32 ldovbb_vset_mask;
 110
 111        struct ti_abb_info *info;
 112        int current_info_idx;
 113
 114        u32 settling_time;
 115};
 116
 117/**
 118 * ti_abb_rmw() - handy wrapper to set specific register bits
 119 * @mask:       mask for register field
 120 * @value:      value shifted to mask location and written
 121 * @offset:     offset of register
 122 * @base:       base address
 123 *
 124 * Return: final register value (may be unused)
 125 */
 126static inline u32 ti_abb_rmw(u32 mask, u32 value, u32 offset,
 127                             void __iomem *base)
 128{
 129        u32 val;
 130
 131        val = readl(base + offset);
 132        val &= ~mask;
 133        val |= (value << __ffs(mask)) & mask;
 134        writel(val, base + offset);
 135
 136        return val;
 137}
 138
 139/**
 140 * ti_abb_check_txdone() - handy wrapper to check ABB tranxdone status
 141 * @abb:        pointer to the abb instance
 142 *
 143 * Return: true or false
 144 */
 145static inline bool ti_abb_check_txdone(const struct ti_abb *abb)
 146{
 147        return !!(readl(abb->int_base) & abb->txdone_mask);
 148}
 149
 150/**
 151 * ti_abb_clear_txdone() - handy wrapper to clear ABB tranxdone status
 152 * @abb:        pointer to the abb instance
 153 */
 154static inline void ti_abb_clear_txdone(const struct ti_abb *abb)
 155{
 156        writel(abb->txdone_mask, abb->int_base);
 157};
 158
 159/**
 160 * ti_abb_wait_tranx() - waits for ABB tranxdone event
 161 * @dev:        device
 162 * @abb:        pointer to the abb instance
 163 *
 164 * Return: 0 on success or -ETIMEDOUT if the event is not cleared on time.
 165 */
 166static int ti_abb_wait_txdone(struct device *dev, struct ti_abb *abb)
 167{
 168        int timeout = 0;
 169        bool status;
 170
 171        while (timeout++ <= abb->settling_time) {
 172                status = ti_abb_check_txdone(abb);
 173                if (status)
 174                        break;
 175
 176                udelay(1);
 177        }
 178
 179        if (timeout > abb->settling_time) {
 180                dev_warn_ratelimited(dev,
 181                                     "%s:TRANXDONE timeout(%duS) int=0x%08x\n",
 182                                     __func__, timeout, readl(abb->int_base));
 183                return -ETIMEDOUT;
 184        }
 185
 186        return 0;
 187}
 188
 189/**
 190 * ti_abb_clear_all_txdone() - clears ABB tranxdone event
 191 * @dev:        device
 192 * @abb:        pointer to the abb instance
 193 *
 194 * Return: 0 on success or -ETIMEDOUT if the event is not cleared on time.
 195 */
 196static int ti_abb_clear_all_txdone(struct device *dev, const struct ti_abb *abb)
 197{
 198        int timeout = 0;
 199        bool status;
 200
 201        while (timeout++ <= abb->settling_time) {
 202                ti_abb_clear_txdone(abb);
 203
 204                status = ti_abb_check_txdone(abb);
 205                if (!status)
 206                        break;
 207
 208                udelay(1);
 209        }
 210
 211        if (timeout > abb->settling_time) {
 212                dev_warn_ratelimited(dev,
 213                                     "%s:TRANXDONE timeout(%duS) int=0x%08x\n",
 214                                     __func__, timeout, readl(abb->int_base));
 215                return -ETIMEDOUT;
 216        }
 217
 218        return 0;
 219}
 220
 221/**
 222 * ti_abb_program_ldovbb() - program LDOVBB register for override value
 223 * @dev:        device
 224 * @abb:        pointer to the abb instance
 225 * @info:       ABB info to program
 226 */
 227static void ti_abb_program_ldovbb(struct device *dev, const struct ti_abb *abb,
 228                                  struct ti_abb_info *info)
 229{
 230        u32 val;
 231
 232        val = readl(abb->ldo_base);
 233        /* clear up previous values */
 234        val &= ~(abb->ldovbb_override_mask | abb->ldovbb_vset_mask);
 235
 236        switch (info->opp_sel) {
 237        case TI_ABB_SLOW_OPP:
 238        case TI_ABB_FAST_OPP:
 239                val |= abb->ldovbb_override_mask;
 240                val |= info->vset << __ffs(abb->ldovbb_vset_mask);
 241                break;
 242        }
 243
 244        writel(val, abb->ldo_base);
 245}
 246
 247/**
 248 * ti_abb_set_opp() - Setup ABB and LDO VBB for required bias
 249 * @rdev:       regulator device
 250 * @abb:        pointer to the abb instance
 251 * @info:       ABB info to program
 252 *
 253 * Return: 0 on success or appropriate error value when fails
 254 */
 255static int ti_abb_set_opp(struct regulator_dev *rdev, struct ti_abb *abb,
 256                          struct ti_abb_info *info)
 257{
 258        const struct ti_abb_reg *regs = abb->regs;
 259        struct device *dev = &rdev->dev;
 260        int ret;
 261
 262        ret = ti_abb_clear_all_txdone(dev, abb);
 263        if (ret)
 264                goto out;
 265
 266        ti_abb_rmw(regs->fbb_sel_mask | regs->rbb_sel_mask, 0, regs->setup_reg,
 267                   abb->base);
 268
 269        switch (info->opp_sel) {
 270        case TI_ABB_SLOW_OPP:
 271                ti_abb_rmw(regs->rbb_sel_mask, 1, regs->setup_reg, abb->base);
 272                break;
 273        case TI_ABB_FAST_OPP:
 274                ti_abb_rmw(regs->fbb_sel_mask, 1, regs->setup_reg, abb->base);
 275                break;
 276        }
 277
 278        /* program next state of ABB ldo */
 279        ti_abb_rmw(regs->opp_sel_mask, info->opp_sel, regs->control_reg,
 280                   abb->base);
 281
 282        /*
 283         * program LDO VBB vset override if needed for !bypass mode
 284         * XXX: Do not switch sequence - for !bypass, LDO override reset *must*
 285         * be performed *before* switch to bias mode else VBB glitches.
 286         */
 287        if (abb->ldo_base && info->opp_sel != TI_ABB_NOMINAL_OPP)
 288                ti_abb_program_ldovbb(dev, abb, info);
 289
 290        /* Initiate ABB ldo change */
 291        ti_abb_rmw(regs->opp_change_mask, 1, regs->control_reg, abb->base);
 292
 293        /* Wait for ABB LDO to complete transition to new Bias setting */
 294        ret = ti_abb_wait_txdone(dev, abb);
 295        if (ret)
 296                goto out;
 297
 298        ret = ti_abb_clear_all_txdone(dev, abb);
 299        if (ret)
 300                goto out;
 301
 302        /*
 303         * Reset LDO VBB vset override bypass mode
 304         * XXX: Do not switch sequence - for bypass, LDO override reset *must*
 305         * be performed *after* switch to bypass else VBB glitches.
 306         */
 307        if (abb->ldo_base && info->opp_sel == TI_ABB_NOMINAL_OPP)
 308                ti_abb_program_ldovbb(dev, abb, info);
 309
 310out:
 311        return ret;
 312}
 313
 314/**
 315 * ti_abb_set_voltage_sel() - regulator accessor function to set ABB LDO
 316 * @rdev:       regulator device
 317 * @sel:        selector to index into required ABB LDO settings (maps to
 318 *              regulator descriptor's volt_table)
 319 *
 320 * Return: 0 on success or appropriate error value when fails
 321 */
 322static int ti_abb_set_voltage_sel(struct regulator_dev *rdev, unsigned sel)
 323{
 324        const struct regulator_desc *desc = rdev->desc;
 325        struct ti_abb *abb = rdev_get_drvdata(rdev);
 326        struct device *dev = &rdev->dev;
 327        struct ti_abb_info *info, *oinfo;
 328        int ret = 0;
 329
 330        if (!abb) {
 331                dev_err_ratelimited(dev, "%s: No regulator drvdata\n",
 332                                    __func__);
 333                return -ENODEV;
 334        }
 335
 336        if (!desc->n_voltages || !abb->info) {
 337                dev_err_ratelimited(dev,
 338                                    "%s: No valid voltage table entries?\n",
 339                                    __func__);
 340                return -EINVAL;
 341        }
 342
 343        if (sel >= desc->n_voltages) {
 344                dev_err(dev, "%s: sel idx(%d) >= n_voltages(%d)\n", __func__,
 345                        sel, desc->n_voltages);
 346                return -EINVAL;
 347        }
 348
 349        /* If we are in the same index as we were, nothing to do here! */
 350        if (sel == abb->current_info_idx) {
 351                dev_dbg(dev, "%s: Already at sel=%d\n", __func__, sel);
 352                return ret;
 353        }
 354
 355        /* If data is exactly the same, then just update index, no change */
 356        info = &abb->info[sel];
 357        oinfo = &abb->info[abb->current_info_idx];
 358        if (!memcmp(info, oinfo, sizeof(*info))) {
 359                dev_dbg(dev, "%s: Same data new idx=%d, old idx=%d\n", __func__,
 360                        sel, abb->current_info_idx);
 361                goto out;
 362        }
 363
 364        ret = ti_abb_set_opp(rdev, abb, info);
 365
 366out:
 367        if (!ret)
 368                abb->current_info_idx = sel;
 369        else
 370                dev_err_ratelimited(dev,
 371                                    "%s: Volt[%d] idx[%d] mode[%d] Fail(%d)\n",
 372                                    __func__, desc->volt_table[sel], sel,
 373                                    info->opp_sel, ret);
 374        return ret;
 375}
 376
 377/**
 378 * ti_abb_get_voltage_sel() - Regulator accessor to get current ABB LDO setting
 379 * @rdev:       regulator device
 380 *
 381 * Return: 0 on success or appropriate error value when fails
 382 */
 383static int ti_abb_get_voltage_sel(struct regulator_dev *rdev)
 384{
 385        const struct regulator_desc *desc = rdev->desc;
 386        struct ti_abb *abb = rdev_get_drvdata(rdev);
 387        struct device *dev = &rdev->dev;
 388
 389        if (!abb) {
 390                dev_err_ratelimited(dev, "%s: No regulator drvdata\n",
 391                                    __func__);
 392                return -ENODEV;
 393        }
 394
 395        if (!desc->n_voltages || !abb->info) {
 396                dev_err_ratelimited(dev,
 397                                    "%s: No valid voltage table entries?\n",
 398                                    __func__);
 399                return -EINVAL;
 400        }
 401
 402        if (abb->current_info_idx >= (int)desc->n_voltages) {
 403                dev_err(dev, "%s: Corrupted data? idx(%d) >= n_voltages(%d)\n",
 404                        __func__, abb->current_info_idx, desc->n_voltages);
 405                return -EINVAL;
 406        }
 407
 408        return abb->current_info_idx;
 409}
 410
 411/**
 412 * ti_abb_init_timings() - setup ABB clock timing for the current platform
 413 * @dev:        device
 414 * @abb:        pointer to the abb instance
 415 *
 416 * Return: 0 if timing is updated, else returns error result.
 417 */
 418static int ti_abb_init_timings(struct device *dev, struct ti_abb *abb)
 419{
 420        u32 clock_cycles;
 421        u32 clk_rate, sr2_wt_cnt_val, cycle_rate;
 422        const struct ti_abb_reg *regs = abb->regs;
 423        int ret;
 424        char *pname = "ti,settling-time";
 425
 426        /* read device tree properties */
 427        ret = of_property_read_u32(dev->of_node, pname, &abb->settling_time);
 428        if (ret) {
 429                dev_err(dev, "Unable to get property '%s'(%d)\n", pname, ret);
 430                return ret;
 431        }
 432
 433        /* ABB LDO cannot be settle in 0 time */
 434        if (!abb->settling_time) {
 435                dev_err(dev, "Invalid property:'%s' set as 0!\n", pname);
 436                return -EINVAL;
 437        }
 438
 439        pname = "ti,clock-cycles";
 440        ret = of_property_read_u32(dev->of_node, pname, &clock_cycles);
 441        if (ret) {
 442                dev_err(dev, "Unable to get property '%s'(%d)\n", pname, ret);
 443                return ret;
 444        }
 445        /* ABB LDO cannot be settle in 0 clock cycles */
 446        if (!clock_cycles) {
 447                dev_err(dev, "Invalid property:'%s' set as 0!\n", pname);
 448                return -EINVAL;
 449        }
 450
 451        abb->clk = devm_clk_get(dev, NULL);
 452        if (IS_ERR(abb->clk)) {
 453                ret = PTR_ERR(abb->clk);
 454                dev_err(dev, "%s: Unable to get clk(%d)\n", __func__, ret);
 455                return ret;
 456        }
 457
 458        /*
 459         * SR2_WTCNT_VALUE is the settling time for the ABB ldo after a
 460         * transition and must be programmed with the correct time at boot.
 461         * The value programmed into the register is the number of SYS_CLK
 462         * clock cycles that match a given wall time profiled for the ldo.
 463         * This value depends on:
 464         * settling time of ldo in micro-seconds (varies per OMAP family)
 465         * # of clock cycles per SYS_CLK period (varies per OMAP family)
 466         * the SYS_CLK frequency in MHz (varies per board)
 467         * The formula is:
 468         *
 469         *                      ldo settling time (in micro-seconds)
 470         * SR2_WTCNT_VALUE = ------------------------------------------
 471         *                   (# system clock cycles) * (sys_clk period)
 472         *
 473         * Put another way:
 474         *
 475         * SR2_WTCNT_VALUE = settling time / (# SYS_CLK cycles / SYS_CLK rate))
 476         *
 477         * To avoid dividing by zero multiply both "# clock cycles" and
 478         * "settling time" by 10 such that the final result is the one we want.
 479         */
 480
 481        /* Convert SYS_CLK rate to MHz & prevent divide by zero */
 482        clk_rate = DIV_ROUND_CLOSEST(clk_get_rate(abb->clk), 1000000);
 483
 484        /* Calculate cycle rate */
 485        cycle_rate = DIV_ROUND_CLOSEST(clock_cycles * 10, clk_rate);
 486
 487        /* Calulate SR2_WTCNT_VALUE */
 488        sr2_wt_cnt_val = DIV_ROUND_CLOSEST(abb->settling_time * 10, cycle_rate);
 489
 490        dev_dbg(dev, "%s: Clk_rate=%ld, sr2_cnt=0x%08x\n", __func__,
 491                clk_get_rate(abb->clk), sr2_wt_cnt_val);
 492
 493        ti_abb_rmw(regs->sr2_wtcnt_value_mask, sr2_wt_cnt_val, regs->setup_reg,
 494                   abb->base);
 495
 496        return 0;
 497}
 498
 499/**
 500 * ti_abb_init_table() - Initialize ABB table from device tree
 501 * @dev:        device
 502 * @abb:        pointer to the abb instance
 503 * @rinit_data: regulator initdata
 504 *
 505 * Return: 0 on success or appropriate error value when fails
 506 */
 507static int ti_abb_init_table(struct device *dev, struct ti_abb *abb,
 508                             struct regulator_init_data *rinit_data)
 509{
 510        struct ti_abb_info *info;
 511        const struct property *prop;
 512        const __be32 *abb_info;
 513        const u32 num_values = 6;
 514        char *pname = "ti,abb_info";
 515        u32 num_entries, i;
 516        unsigned int *volt_table;
 517        int min_uV = INT_MAX, max_uV = 0;
 518        struct regulation_constraints *c = &rinit_data->constraints;
 519
 520        prop = of_find_property(dev->of_node, pname, NULL);
 521        if (!prop) {
 522                dev_err(dev, "No '%s' property?\n", pname);
 523                return -ENODEV;
 524        }
 525
 526        if (!prop->value) {
 527                dev_err(dev, "Empty '%s' property?\n", pname);
 528                return -ENODATA;
 529        }
 530
 531        /*
 532         * Each abb_info is a set of n-tuple, where n is num_values, consisting
 533         * of voltage and a set of detection logic for ABB information for that
 534         * voltage to apply.
 535         */
 536        num_entries = prop->length / sizeof(u32);
 537        if (!num_entries || (num_entries % num_values)) {
 538                dev_err(dev, "All '%s' list entries need %d vals\n", pname,
 539                        num_values);
 540                return -EINVAL;
 541        }
 542        num_entries /= num_values;
 543
 544        info = devm_kzalloc(dev, sizeof(*info) * num_entries, GFP_KERNEL);
 545        if (!info) {
 546                dev_err(dev, "Can't allocate info table for '%s' property\n",
 547                        pname);
 548                return -ENOMEM;
 549        }
 550        abb->info = info;
 551
 552        volt_table = devm_kzalloc(dev, sizeof(unsigned int) * num_entries,
 553                                  GFP_KERNEL);
 554        if (!volt_table) {
 555                dev_err(dev, "Can't allocate voltage table for '%s' property\n",
 556                        pname);
 557                return -ENOMEM;
 558        }
 559
 560        abb->rdesc.n_voltages = num_entries;
 561        abb->rdesc.volt_table = volt_table;
 562        /* We do not know where the OPP voltage is at the moment */
 563        abb->current_info_idx = -EINVAL;
 564
 565        abb_info = prop->value;
 566        for (i = 0; i < num_entries; i++, info++, volt_table++) {
 567                u32 efuse_offset, rbb_mask, fbb_mask, vset_mask;
 568                u32 efuse_val;
 569
 570                /* NOTE: num_values should equal to entries picked up here */
 571                *volt_table = be32_to_cpup(abb_info++);
 572                info->opp_sel = be32_to_cpup(abb_info++);
 573                efuse_offset = be32_to_cpup(abb_info++);
 574                rbb_mask = be32_to_cpup(abb_info++);
 575                fbb_mask = be32_to_cpup(abb_info++);
 576                vset_mask = be32_to_cpup(abb_info++);
 577
 578                dev_dbg(dev,
 579                        "[%d]v=%d ABB=%d ef=0x%x rbb=0x%x fbb=0x%x vset=0x%x\n",
 580                        i, *volt_table, info->opp_sel, efuse_offset, rbb_mask,
 581                        fbb_mask, vset_mask);
 582
 583                /* Find min/max for voltage set */
 584                if (min_uV > *volt_table)
 585                        min_uV = *volt_table;
 586                if (max_uV < *volt_table)
 587                        max_uV = *volt_table;
 588
 589                if (!abb->efuse_base) {
 590                        /* Ignore invalid data, but warn to help cleanup */
 591                        if (efuse_offset || rbb_mask || fbb_mask || vset_mask)
 592                                dev_err(dev, "prop '%s': v=%d,bad efuse/mask\n",
 593                                        pname, *volt_table);
 594                        goto check_abb;
 595                }
 596
 597                efuse_val = readl(abb->efuse_base + efuse_offset);
 598
 599                /* Use ABB recommendation from Efuse */
 600                if (efuse_val & rbb_mask)
 601                        info->opp_sel = TI_ABB_SLOW_OPP;
 602                else if (efuse_val & fbb_mask)
 603                        info->opp_sel = TI_ABB_FAST_OPP;
 604                else if (rbb_mask || fbb_mask)
 605                        info->opp_sel = TI_ABB_NOMINAL_OPP;
 606
 607                dev_dbg(dev,
 608                        "[%d]v=%d efusev=0x%x final ABB=%d\n",
 609                        i, *volt_table, efuse_val, info->opp_sel);
 610
 611                /* Use recommended Vset bits from Efuse */
 612                if (!abb->ldo_base) {
 613                        if (vset_mask)
 614                                dev_err(dev, "prop'%s':v=%d vst=%x LDO base?\n",
 615                                        pname, *volt_table, vset_mask);
 616                        continue;
 617                }
 618                info->vset = efuse_val & vset_mask >> __ffs(vset_mask);
 619                dev_dbg(dev, "[%d]v=%d vset=%x\n", i, *volt_table, info->vset);
 620check_abb:
 621                switch (info->opp_sel) {
 622                case TI_ABB_NOMINAL_OPP:
 623                case TI_ABB_FAST_OPP:
 624                case TI_ABB_SLOW_OPP:
 625                        /* Valid values */
 626                        break;
 627                default:
 628                        dev_err(dev, "%s:[%d]v=%d, ABB=%d is invalid! Abort!\n",
 629                                __func__, i, *volt_table, info->opp_sel);
 630                        return -EINVAL;
 631                }
 632        }
 633
 634        /* Setup the min/max voltage constraints from the supported list */
 635        c->min_uV = min_uV;
 636        c->max_uV = max_uV;
 637
 638        return 0;
 639}
 640
 641static struct regulator_ops ti_abb_reg_ops = {
 642        .list_voltage = regulator_list_voltage_table,
 643
 644        .set_voltage_sel = ti_abb_set_voltage_sel,
 645        .get_voltage_sel = ti_abb_get_voltage_sel,
 646};
 647
 648/* Default ABB block offsets, IF this changes in future, create new one */
 649static const struct ti_abb_reg abb_regs_v1 = {
 650        /* WARNING: registers are wrongly documented in TRM */
 651        .setup_reg              = 0x04,
 652        .control_reg            = 0x00,
 653
 654        .sr2_wtcnt_value_mask   = (0xff << 8),
 655        .fbb_sel_mask           = (0x01 << 2),
 656        .rbb_sel_mask           = (0x01 << 1),
 657        .sr2_en_mask            = (0x01 << 0),
 658
 659        .opp_change_mask        = (0x01 << 2),
 660        .opp_sel_mask           = (0x03 << 0),
 661};
 662
 663static const struct ti_abb_reg abb_regs_v2 = {
 664        .setup_reg              = 0x00,
 665        .control_reg            = 0x04,
 666
 667        .sr2_wtcnt_value_mask   = (0xff << 8),
 668        .fbb_sel_mask           = (0x01 << 2),
 669        .rbb_sel_mask           = (0x01 << 1),
 670        .sr2_en_mask            = (0x01 << 0),
 671
 672        .opp_change_mask        = (0x01 << 2),
 673        .opp_sel_mask           = (0x03 << 0),
 674};
 675
 676static const struct of_device_id ti_abb_of_match[] = {
 677        {.compatible = "ti,abb-v1", .data = &abb_regs_v1},
 678        {.compatible = "ti,abb-v2", .data = &abb_regs_v2},
 679        { },
 680};
 681
 682MODULE_DEVICE_TABLE(of, ti_abb_of_match);
 683
 684/**
 685 * ti_abb_probe() - Initialize an ABB ldo instance
 686 * @pdev: ABB platform device
 687 *
 688 * Initializes an individual ABB LDO for required Body-Bias. ABB is used to
 689 * addional bias supply to SoC modules for power savings or mandatory stability
 690 * configuration at certain Operating Performance Points(OPPs).
 691 *
 692 * Return: 0 on success or appropriate error value when fails
 693 */
 694static int ti_abb_probe(struct platform_device *pdev)
 695{
 696        struct device *dev = &pdev->dev;
 697        const struct of_device_id *match;
 698        struct resource *res;
 699        struct ti_abb *abb;
 700        struct regulator_init_data *initdata = NULL;
 701        struct regulator_dev *rdev = NULL;
 702        struct regulator_desc *desc;
 703        struct regulation_constraints *c;
 704        struct regulator_config config = { };
 705        char *pname;
 706        int ret = 0;
 707
 708        match = of_match_device(ti_abb_of_match, dev);
 709        if (!match) {
 710                /* We do not expect this to happen */
 711                ret = -ENODEV;
 712                dev_err(dev, "%s: Unable to match device\n", __func__);
 713                goto err;
 714        }
 715        if (!match->data) {
 716                ret = -EINVAL;
 717                dev_err(dev, "%s: Bad data in match\n", __func__);
 718                goto err;
 719        }
 720
 721        abb = devm_kzalloc(dev, sizeof(struct ti_abb), GFP_KERNEL);
 722        if (!abb) {
 723                dev_err(dev, "%s: Unable to allocate ABB struct\n", __func__);
 724                ret = -ENOMEM;
 725                goto err;
 726        }
 727        abb->regs = match->data;
 728
 729        /* Map ABB resources */
 730        pname = "base-address";
 731        res = platform_get_resource_byname(pdev, IORESOURCE_MEM, pname);
 732        abb->base = devm_ioremap_resource(dev, res);
 733        if (IS_ERR(abb->base)) {
 734                ret = PTR_ERR(abb->base);
 735                goto err;
 736        }
 737
 738        pname = "int-address";
 739        res = platform_get_resource_byname(pdev, IORESOURCE_MEM, pname);
 740        if (!res) {
 741                dev_err(dev, "Missing '%s' IO resource\n", pname);
 742                ret = -ENODEV;
 743                goto err;
 744        }
 745        /*
 746         * We may have shared interrupt register offsets which are
 747         * write-1-to-clear between domains ensuring exclusivity.
 748         */
 749        abb->int_base = devm_ioremap_nocache(dev, res->start,
 750                                             resource_size(res));
 751        if (!abb->int_base) {
 752                dev_err(dev, "Unable to map '%s'\n", pname);
 753                ret = -ENOMEM;
 754                goto err;
 755        }
 756
 757        /* Map Optional resources */
 758        pname = "efuse-address";
 759        res = platform_get_resource_byname(pdev, IORESOURCE_MEM, pname);
 760        if (!res) {
 761                dev_dbg(dev, "Missing '%s' IO resource\n", pname);
 762                ret = -ENODEV;
 763                goto skip_opt;
 764        }
 765
 766        /*
 767         * We may have shared efuse register offsets which are read-only
 768         * between domains
 769         */
 770        abb->efuse_base = devm_ioremap_nocache(dev, res->start,
 771                                               resource_size(res));
 772        if (!abb->efuse_base) {
 773                dev_err(dev, "Unable to map '%s'\n", pname);
 774                ret = -ENOMEM;
 775                goto err;
 776        }
 777
 778        pname = "ldo-address";
 779        res = platform_get_resource_byname(pdev, IORESOURCE_MEM, pname);
 780        abb->ldo_base = devm_ioremap_resource(dev, res);
 781        if (IS_ERR(abb->ldo_base)) {
 782                ret = PTR_ERR(abb->ldo_base);
 783                goto err;
 784        }
 785
 786        /* IF ldo_base is set, the following are mandatory */
 787        pname = "ti,ldovbb-override-mask";
 788        ret =
 789            of_property_read_u32(pdev->dev.of_node, pname,
 790                                 &abb->ldovbb_override_mask);
 791        if (ret) {
 792                dev_err(dev, "Missing '%s' (%d)\n", pname, ret);
 793                goto err;
 794        }
 795        if (!abb->ldovbb_override_mask) {
 796                dev_err(dev, "Invalid property:'%s' set as 0!\n", pname);
 797                ret = -EINVAL;
 798                goto err;
 799        }
 800
 801        pname = "ti,ldovbb-vset-mask";
 802        ret =
 803            of_property_read_u32(pdev->dev.of_node, pname,
 804                                 &abb->ldovbb_vset_mask);
 805        if (ret) {
 806                dev_err(dev, "Missing '%s' (%d)\n", pname, ret);
 807                goto err;
 808        }
 809        if (!abb->ldovbb_vset_mask) {
 810                dev_err(dev, "Invalid property:'%s' set as 0!\n", pname);
 811                ret = -EINVAL;
 812                goto err;
 813        }
 814
 815skip_opt:
 816        pname = "ti,tranxdone-status-mask";
 817        ret =
 818            of_property_read_u32(pdev->dev.of_node, pname,
 819                                 &abb->txdone_mask);
 820        if (ret) {
 821                dev_err(dev, "Missing '%s' (%d)\n", pname, ret);
 822                goto err;
 823        }
 824        if (!abb->txdone_mask) {
 825                dev_err(dev, "Invalid property:'%s' set as 0!\n", pname);
 826                ret = -EINVAL;
 827                goto err;
 828        }
 829
 830        initdata = of_get_regulator_init_data(dev, pdev->dev.of_node);
 831        if (!initdata) {
 832                ret = -ENOMEM;
 833                dev_err(dev, "%s: Unable to alloc regulator init data\n",
 834                        __func__);
 835                goto err;
 836        }
 837
 838        /* init ABB opp_sel table */
 839        ret = ti_abb_init_table(dev, abb, initdata);
 840        if (ret)
 841                goto err;
 842
 843        /* init ABB timing */
 844        ret = ti_abb_init_timings(dev, abb);
 845        if (ret)
 846                goto err;
 847
 848        desc = &abb->rdesc;
 849        desc->name = dev_name(dev);
 850        desc->owner = THIS_MODULE;
 851        desc->type = REGULATOR_VOLTAGE;
 852        desc->ops = &ti_abb_reg_ops;
 853
 854        c = &initdata->constraints;
 855        if (desc->n_voltages > 1)
 856                c->valid_ops_mask |= REGULATOR_CHANGE_VOLTAGE;
 857        c->always_on = true;
 858
 859        config.dev = dev;
 860        config.init_data = initdata;
 861        config.driver_data = abb;
 862        config.of_node = pdev->dev.of_node;
 863
 864        rdev = regulator_register(desc, &config);
 865        if (IS_ERR(rdev)) {
 866                ret = PTR_ERR(rdev);
 867                dev_err(dev, "%s: failed to register regulator(%d)\n",
 868                        __func__, ret);
 869                goto err;
 870        }
 871        platform_set_drvdata(pdev, rdev);
 872
 873        /* Enable the ldo if not already done by bootloader */
 874        ti_abb_rmw(abb->regs->sr2_en_mask, 1, abb->regs->setup_reg, abb->base);
 875
 876        return 0;
 877
 878err:
 879        dev_err(dev, "%s: Failed to initialize(%d)\n", __func__, ret);
 880        return ret;
 881}
 882
 883/**
 884 * ti_abb_remove() - cleanups
 885 * @pdev: ABB platform device
 886 *
 887 * Return: 0
 888 */
 889static int ti_abb_remove(struct platform_device *pdev)
 890{
 891        struct regulator_dev *rdev = platform_get_drvdata(pdev);
 892
 893        regulator_unregister(rdev);
 894        return 0;
 895}
 896
 897MODULE_ALIAS("platform:ti_abb");
 898
 899static struct platform_driver ti_abb_driver = {
 900        .probe = ti_abb_probe,
 901        .remove = ti_abb_remove,
 902        .driver = {
 903                   .name = "ti_abb",
 904                   .owner = THIS_MODULE,
 905                   .of_match_table = of_match_ptr(ti_abb_of_match),
 906                   },
 907};
 908module_platform_driver(ti_abb_driver);
 909
 910MODULE_DESCRIPTION("Texas Instruments ABB LDO regulator driver");
 911MODULE_AUTHOR("Texas Instruments Inc.");
 912MODULE_LICENSE("GPL v2");
 913
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