linux/drivers/pinctrl/samsung/pinctrl-samsung.c
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   1/*
   2 * pin-controller/pin-mux/pin-config/gpio-driver for Samsung's SoC's.
   3 *
   4 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
   5 *              http://www.samsung.com
   6 * Copyright (c) 2012 Linaro Ltd
   7 *              http://www.linaro.org
   8 *
   9 * Author: Thomas Abraham <thomas.ab@samsung.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 as published by
  13 * the Free Software Foundation; either version 2 of the License, or
  14 * (at your option) any later version.
  15 *
  16 * This driver implements the Samsung pinctrl driver. It supports setting up of
  17 * pinmux and pinconf configurations. The gpiolib interface is also included.
  18 * External interrupt (gpio and wakeup) support are not included in this driver
  19 * but provides extensions to which platform specific implementation of the gpio
  20 * and wakeup interrupts can be hooked to.
  21 */
  22
  23#include <linux/module.h>
  24#include <linux/platform_device.h>
  25#include <linux/io.h>
  26#include <linux/slab.h>
  27#include <linux/err.h>
  28#include <linux/gpio.h>
  29#include <linux/irqdomain.h>
  30#include <linux/spinlock.h>
  31#include <linux/syscore_ops.h>
  32
  33#include "../core.h"
  34#include "pinctrl-samsung.h"
  35
  36/* list of all possible config options supported */
  37static struct pin_config {
  38        const char *property;
  39        enum pincfg_type param;
  40} cfg_params[] = {
  41        { "samsung,pin-pud", PINCFG_TYPE_PUD },
  42        { "samsung,pin-drv", PINCFG_TYPE_DRV },
  43        { "samsung,pin-con-pdn", PINCFG_TYPE_CON_PDN },
  44        { "samsung,pin-pud-pdn", PINCFG_TYPE_PUD_PDN },
  45        { "samsung,pin-val", PINCFG_TYPE_DAT },
  46};
  47
  48/* Global list of devices (struct samsung_pinctrl_drv_data) */
  49static LIST_HEAD(drvdata_list);
  50
  51static unsigned int pin_base;
  52
  53static int samsung_get_group_count(struct pinctrl_dev *pctldev)
  54{
  55        struct samsung_pinctrl_drv_data *pmx = pinctrl_dev_get_drvdata(pctldev);
  56
  57        return pmx->nr_groups;
  58}
  59
  60static const char *samsung_get_group_name(struct pinctrl_dev *pctldev,
  61                                                unsigned group)
  62{
  63        struct samsung_pinctrl_drv_data *pmx = pinctrl_dev_get_drvdata(pctldev);
  64
  65        return pmx->pin_groups[group].name;
  66}
  67
  68static int samsung_get_group_pins(struct pinctrl_dev *pctldev,
  69                                        unsigned group,
  70                                        const unsigned **pins,
  71                                        unsigned *num_pins)
  72{
  73        struct samsung_pinctrl_drv_data *pmx = pinctrl_dev_get_drvdata(pctldev);
  74
  75        *pins = pmx->pin_groups[group].pins;
  76        *num_pins = pmx->pin_groups[group].num_pins;
  77
  78        return 0;
  79}
  80
  81static int reserve_map(struct device *dev, struct pinctrl_map **map,
  82                       unsigned *reserved_maps, unsigned *num_maps,
  83                       unsigned reserve)
  84{
  85        unsigned old_num = *reserved_maps;
  86        unsigned new_num = *num_maps + reserve;
  87        struct pinctrl_map *new_map;
  88
  89        if (old_num >= new_num)
  90                return 0;
  91
  92        new_map = krealloc(*map, sizeof(*new_map) * new_num, GFP_KERNEL);
  93        if (!new_map) {
  94                dev_err(dev, "krealloc(map) failed\n");
  95                return -ENOMEM;
  96        }
  97
  98        memset(new_map + old_num, 0, (new_num - old_num) * sizeof(*new_map));
  99
 100        *map = new_map;
 101        *reserved_maps = new_num;
 102
 103        return 0;
 104}
 105
 106static int add_map_mux(struct pinctrl_map **map, unsigned *reserved_maps,
 107                       unsigned *num_maps, const char *group,
 108                       const char *function)
 109{
 110        if (WARN_ON(*num_maps == *reserved_maps))
 111                return -ENOSPC;
 112
 113        (*map)[*num_maps].type = PIN_MAP_TYPE_MUX_GROUP;
 114        (*map)[*num_maps].data.mux.group = group;
 115        (*map)[*num_maps].data.mux.function = function;
 116        (*num_maps)++;
 117
 118        return 0;
 119}
 120
 121static int add_map_configs(struct device *dev, struct pinctrl_map **map,
 122                           unsigned *reserved_maps, unsigned *num_maps,
 123                           const char *group, unsigned long *configs,
 124                           unsigned num_configs)
 125{
 126        unsigned long *dup_configs;
 127
 128        if (WARN_ON(*num_maps == *reserved_maps))
 129                return -ENOSPC;
 130
 131        dup_configs = kmemdup(configs, num_configs * sizeof(*dup_configs),
 132                              GFP_KERNEL);
 133        if (!dup_configs) {
 134                dev_err(dev, "kmemdup(configs) failed\n");
 135                return -ENOMEM;
 136        }
 137
 138        (*map)[*num_maps].type = PIN_MAP_TYPE_CONFIGS_GROUP;
 139        (*map)[*num_maps].data.configs.group_or_pin = group;
 140        (*map)[*num_maps].data.configs.configs = dup_configs;
 141        (*map)[*num_maps].data.configs.num_configs = num_configs;
 142        (*num_maps)++;
 143
 144        return 0;
 145}
 146
 147static int add_config(struct device *dev, unsigned long **configs,
 148                      unsigned *num_configs, unsigned long config)
 149{
 150        unsigned old_num = *num_configs;
 151        unsigned new_num = old_num + 1;
 152        unsigned long *new_configs;
 153
 154        new_configs = krealloc(*configs, sizeof(*new_configs) * new_num,
 155                               GFP_KERNEL);
 156        if (!new_configs) {
 157                dev_err(dev, "krealloc(configs) failed\n");
 158                return -ENOMEM;
 159        }
 160
 161        new_configs[old_num] = config;
 162
 163        *configs = new_configs;
 164        *num_configs = new_num;
 165
 166        return 0;
 167}
 168
 169static void samsung_dt_free_map(struct pinctrl_dev *pctldev,
 170                                      struct pinctrl_map *map,
 171                                      unsigned num_maps)
 172{
 173        int i;
 174
 175        for (i = 0; i < num_maps; i++)
 176                if (map[i].type == PIN_MAP_TYPE_CONFIGS_GROUP)
 177                        kfree(map[i].data.configs.configs);
 178
 179        kfree(map);
 180}
 181
 182static int samsung_dt_subnode_to_map(struct samsung_pinctrl_drv_data *drvdata,
 183                                     struct device *dev,
 184                                     struct device_node *np,
 185                                     struct pinctrl_map **map,
 186                                     unsigned *reserved_maps,
 187                                     unsigned *num_maps)
 188{
 189        int ret, i;
 190        u32 val;
 191        unsigned long config;
 192        unsigned long *configs = NULL;
 193        unsigned num_configs = 0;
 194        unsigned reserve;
 195        struct property *prop;
 196        const char *group;
 197        bool has_func = false;
 198
 199        ret = of_property_read_u32(np, "samsung,pin-function", &val);
 200        if (!ret)
 201                has_func = true;
 202
 203        for (i = 0; i < ARRAY_SIZE(cfg_params); i++) {
 204                ret = of_property_read_u32(np, cfg_params[i].property, &val);
 205                if (!ret) {
 206                        config = PINCFG_PACK(cfg_params[i].param, val);
 207                        ret = add_config(dev, &configs, &num_configs, config);
 208                        if (ret < 0)
 209                                goto exit;
 210                /* EINVAL=missing, which is fine since it's optional */
 211                } else if (ret != -EINVAL) {
 212                        dev_err(dev, "could not parse property %s\n",
 213                                cfg_params[i].property);
 214                }
 215        }
 216
 217        reserve = 0;
 218        if (has_func)
 219                reserve++;
 220        if (num_configs)
 221                reserve++;
 222        ret = of_property_count_strings(np, "samsung,pins");
 223        if (ret < 0) {
 224                dev_err(dev, "could not parse property samsung,pins\n");
 225                goto exit;
 226        }
 227        reserve *= ret;
 228
 229        ret = reserve_map(dev, map, reserved_maps, num_maps, reserve);
 230        if (ret < 0)
 231                goto exit;
 232
 233        of_property_for_each_string(np, "samsung,pins", prop, group) {
 234                if (has_func) {
 235                        ret = add_map_mux(map, reserved_maps,
 236                                                num_maps, group, np->full_name);
 237                        if (ret < 0)
 238                                goto exit;
 239                }
 240
 241                if (num_configs) {
 242                        ret = add_map_configs(dev, map, reserved_maps,
 243                                              num_maps, group, configs,
 244                                              num_configs);
 245                        if (ret < 0)
 246                                goto exit;
 247                }
 248        }
 249
 250        ret = 0;
 251
 252exit:
 253        kfree(configs);
 254        return ret;
 255}
 256
 257static int samsung_dt_node_to_map(struct pinctrl_dev *pctldev,
 258                                        struct device_node *np_config,
 259                                        struct pinctrl_map **map,
 260                                        unsigned *num_maps)
 261{
 262        struct samsung_pinctrl_drv_data *drvdata;
 263        unsigned reserved_maps;
 264        struct device_node *np;
 265        int ret;
 266
 267        drvdata = pinctrl_dev_get_drvdata(pctldev);
 268
 269        reserved_maps = 0;
 270        *map = NULL;
 271        *num_maps = 0;
 272
 273        if (!of_get_child_count(np_config))
 274                return samsung_dt_subnode_to_map(drvdata, pctldev->dev,
 275                                                        np_config, map,
 276                                                        &reserved_maps,
 277                                                        num_maps);
 278
 279        for_each_child_of_node(np_config, np) {
 280                ret = samsung_dt_subnode_to_map(drvdata, pctldev->dev, np, map,
 281                                                &reserved_maps, num_maps);
 282                if (ret < 0) {
 283                        samsung_dt_free_map(pctldev, *map, *num_maps);
 284                        return ret;
 285                }
 286        }
 287
 288        return 0;
 289}
 290
 291/* list of pinctrl callbacks for the pinctrl core */
 292static const struct pinctrl_ops samsung_pctrl_ops = {
 293        .get_groups_count       = samsung_get_group_count,
 294        .get_group_name         = samsung_get_group_name,
 295        .get_group_pins         = samsung_get_group_pins,
 296        .dt_node_to_map         = samsung_dt_node_to_map,
 297        .dt_free_map            = samsung_dt_free_map,
 298};
 299
 300/* check if the selector is a valid pin function selector */
 301static int samsung_get_functions_count(struct pinctrl_dev *pctldev)
 302{
 303        struct samsung_pinctrl_drv_data *drvdata;
 304
 305        drvdata = pinctrl_dev_get_drvdata(pctldev);
 306        return drvdata->nr_functions;
 307}
 308
 309/* return the name of the pin function specified */
 310static const char *samsung_pinmux_get_fname(struct pinctrl_dev *pctldev,
 311                                                unsigned selector)
 312{
 313        struct samsung_pinctrl_drv_data *drvdata;
 314
 315        drvdata = pinctrl_dev_get_drvdata(pctldev);
 316        return drvdata->pmx_functions[selector].name;
 317}
 318
 319/* return the groups associated for the specified function selector */
 320static int samsung_pinmux_get_groups(struct pinctrl_dev *pctldev,
 321                unsigned selector, const char * const **groups,
 322                unsigned * const num_groups)
 323{
 324        struct samsung_pinctrl_drv_data *drvdata;
 325
 326        drvdata = pinctrl_dev_get_drvdata(pctldev);
 327        *groups = drvdata->pmx_functions[selector].groups;
 328        *num_groups = drvdata->pmx_functions[selector].num_groups;
 329        return 0;
 330}
 331
 332/*
 333 * given a pin number that is local to a pin controller, find out the pin bank
 334 * and the register base of the pin bank.
 335 */
 336static void pin_to_reg_bank(struct samsung_pinctrl_drv_data *drvdata,
 337                        unsigned pin, void __iomem **reg, u32 *offset,
 338                        struct samsung_pin_bank **bank)
 339{
 340        struct samsung_pin_bank *b;
 341
 342        b = drvdata->pin_banks;
 343
 344        while ((pin >= b->pin_base) &&
 345                        ((b->pin_base + b->nr_pins - 1) < pin))
 346                b++;
 347
 348        *reg = drvdata->virt_base + b->pctl_offset;
 349        *offset = pin - b->pin_base;
 350        if (bank)
 351                *bank = b;
 352}
 353
 354/* enable or disable a pinmux function */
 355static void samsung_pinmux_setup(struct pinctrl_dev *pctldev, unsigned selector,
 356                                        unsigned group, bool enable)
 357{
 358        struct samsung_pinctrl_drv_data *drvdata;
 359        const struct samsung_pin_bank_type *type;
 360        struct samsung_pin_bank *bank;
 361        void __iomem *reg;
 362        u32 mask, shift, data, pin_offset;
 363        unsigned long flags;
 364        const struct samsung_pmx_func *func;
 365        const struct samsung_pin_group *grp;
 366
 367        drvdata = pinctrl_dev_get_drvdata(pctldev);
 368        func = &drvdata->pmx_functions[selector];
 369        grp = &drvdata->pin_groups[group];
 370
 371        pin_to_reg_bank(drvdata, grp->pins[0] - drvdata->pin_base,
 372                        &reg, &pin_offset, &bank);
 373        type = bank->type;
 374        mask = (1 << type->fld_width[PINCFG_TYPE_FUNC]) - 1;
 375        shift = pin_offset * type->fld_width[PINCFG_TYPE_FUNC];
 376        if (shift >= 32) {
 377                /* Some banks have two config registers */
 378                shift -= 32;
 379                reg += 4;
 380        }
 381
 382        spin_lock_irqsave(&bank->slock, flags);
 383
 384        data = readl(reg + type->reg_offset[PINCFG_TYPE_FUNC]);
 385        data &= ~(mask << shift);
 386        if (enable)
 387                data |= func->val << shift;
 388        writel(data, reg + type->reg_offset[PINCFG_TYPE_FUNC]);
 389
 390        spin_unlock_irqrestore(&bank->slock, flags);
 391}
 392
 393/* enable a specified pinmux by writing to registers */
 394static int samsung_pinmux_set_mux(struct pinctrl_dev *pctldev,
 395                                  unsigned selector,
 396                                  unsigned group)
 397{
 398        samsung_pinmux_setup(pctldev, selector, group, true);
 399        return 0;
 400}
 401
 402/* list of pinmux callbacks for the pinmux vertical in pinctrl core */
 403static const struct pinmux_ops samsung_pinmux_ops = {
 404        .get_functions_count    = samsung_get_functions_count,
 405        .get_function_name      = samsung_pinmux_get_fname,
 406        .get_function_groups    = samsung_pinmux_get_groups,
 407        .set_mux                = samsung_pinmux_set_mux,
 408};
 409
 410/* set or get the pin config settings for a specified pin */
 411static int samsung_pinconf_rw(struct pinctrl_dev *pctldev, unsigned int pin,
 412                                unsigned long *config, bool set)
 413{
 414        struct samsung_pinctrl_drv_data *drvdata;
 415        const struct samsung_pin_bank_type *type;
 416        struct samsung_pin_bank *bank;
 417        void __iomem *reg_base;
 418        enum pincfg_type cfg_type = PINCFG_UNPACK_TYPE(*config);
 419        u32 data, width, pin_offset, mask, shift;
 420        u32 cfg_value, cfg_reg;
 421        unsigned long flags;
 422
 423        drvdata = pinctrl_dev_get_drvdata(pctldev);
 424        pin_to_reg_bank(drvdata, pin - drvdata->pin_base, &reg_base,
 425                                        &pin_offset, &bank);
 426        type = bank->type;
 427
 428        if (cfg_type >= PINCFG_TYPE_NUM || !type->fld_width[cfg_type])
 429                return -EINVAL;
 430
 431        width = type->fld_width[cfg_type];
 432        cfg_reg = type->reg_offset[cfg_type];
 433
 434        spin_lock_irqsave(&bank->slock, flags);
 435
 436        mask = (1 << width) - 1;
 437        shift = pin_offset * width;
 438        data = readl(reg_base + cfg_reg);
 439
 440        if (set) {
 441                cfg_value = PINCFG_UNPACK_VALUE(*config);
 442                data &= ~(mask << shift);
 443                data |= (cfg_value << shift);
 444                writel(data, reg_base + cfg_reg);
 445        } else {
 446                data >>= shift;
 447                data &= mask;
 448                *config = PINCFG_PACK(cfg_type, data);
 449        }
 450
 451        spin_unlock_irqrestore(&bank->slock, flags);
 452
 453        return 0;
 454}
 455
 456/* set the pin config settings for a specified pin */
 457static int samsung_pinconf_set(struct pinctrl_dev *pctldev, unsigned int pin,
 458                                unsigned long *configs, unsigned num_configs)
 459{
 460        int i, ret;
 461
 462        for (i = 0; i < num_configs; i++) {
 463                ret = samsung_pinconf_rw(pctldev, pin, &configs[i], true);
 464                if (ret < 0)
 465                        return ret;
 466        } /* for each config */
 467
 468        return 0;
 469}
 470
 471/* get the pin config settings for a specified pin */
 472static int samsung_pinconf_get(struct pinctrl_dev *pctldev, unsigned int pin,
 473                                        unsigned long *config)
 474{
 475        return samsung_pinconf_rw(pctldev, pin, config, false);
 476}
 477
 478/* set the pin config settings for a specified pin group */
 479static int samsung_pinconf_group_set(struct pinctrl_dev *pctldev,
 480                        unsigned group, unsigned long *configs,
 481                        unsigned num_configs)
 482{
 483        struct samsung_pinctrl_drv_data *drvdata;
 484        const unsigned int *pins;
 485        unsigned int cnt;
 486
 487        drvdata = pinctrl_dev_get_drvdata(pctldev);
 488        pins = drvdata->pin_groups[group].pins;
 489
 490        for (cnt = 0; cnt < drvdata->pin_groups[group].num_pins; cnt++)
 491                samsung_pinconf_set(pctldev, pins[cnt], configs, num_configs);
 492
 493        return 0;
 494}
 495
 496/* get the pin config settings for a specified pin group */
 497static int samsung_pinconf_group_get(struct pinctrl_dev *pctldev,
 498                                unsigned int group, unsigned long *config)
 499{
 500        struct samsung_pinctrl_drv_data *drvdata;
 501        const unsigned int *pins;
 502
 503        drvdata = pinctrl_dev_get_drvdata(pctldev);
 504        pins = drvdata->pin_groups[group].pins;
 505        samsung_pinconf_get(pctldev, pins[0], config);
 506        return 0;
 507}
 508
 509/* list of pinconfig callbacks for pinconfig vertical in the pinctrl code */
 510static const struct pinconf_ops samsung_pinconf_ops = {
 511        .pin_config_get         = samsung_pinconf_get,
 512        .pin_config_set         = samsung_pinconf_set,
 513        .pin_config_group_get   = samsung_pinconf_group_get,
 514        .pin_config_group_set   = samsung_pinconf_group_set,
 515};
 516
 517/*
 518 * The samsung_gpio_set_vlaue() should be called with "bank->slock" held
 519 * to avoid race condition.
 520 */
 521static void samsung_gpio_set_value(struct gpio_chip *gc,
 522                                          unsigned offset, int value)
 523{
 524        struct samsung_pin_bank *bank = gpiochip_get_data(gc);
 525        const struct samsung_pin_bank_type *type = bank->type;
 526        void __iomem *reg;
 527        u32 data;
 528
 529        reg = bank->drvdata->virt_base + bank->pctl_offset;
 530
 531        data = readl(reg + type->reg_offset[PINCFG_TYPE_DAT]);
 532        data &= ~(1 << offset);
 533        if (value)
 534                data |= 1 << offset;
 535        writel(data, reg + type->reg_offset[PINCFG_TYPE_DAT]);
 536}
 537
 538/* gpiolib gpio_set callback function */
 539static void samsung_gpio_set(struct gpio_chip *gc, unsigned offset, int value)
 540{
 541        struct samsung_pin_bank *bank = gpiochip_get_data(gc);
 542        unsigned long flags;
 543
 544        spin_lock_irqsave(&bank->slock, flags);
 545        samsung_gpio_set_value(gc, offset, value);
 546        spin_unlock_irqrestore(&bank->slock, flags);
 547}
 548
 549/* gpiolib gpio_get callback function */
 550static int samsung_gpio_get(struct gpio_chip *gc, unsigned offset)
 551{
 552        void __iomem *reg;
 553        u32 data;
 554        struct samsung_pin_bank *bank = gpiochip_get_data(gc);
 555        const struct samsung_pin_bank_type *type = bank->type;
 556
 557        reg = bank->drvdata->virt_base + bank->pctl_offset;
 558
 559        data = readl(reg + type->reg_offset[PINCFG_TYPE_DAT]);
 560        data >>= offset;
 561        data &= 1;
 562        return data;
 563}
 564
 565/*
 566 * The samsung_gpio_set_direction() should be called with "bank->slock" held
 567 * to avoid race condition.
 568 * The calls to gpio_direction_output() and gpio_direction_input()
 569 * leads to this function call.
 570 */
 571static int samsung_gpio_set_direction(struct gpio_chip *gc,
 572                                             unsigned offset, bool input)
 573{
 574        const struct samsung_pin_bank_type *type;
 575        struct samsung_pin_bank *bank;
 576        struct samsung_pinctrl_drv_data *drvdata;
 577        void __iomem *reg;
 578        u32 data, mask, shift;
 579
 580        bank = gpiochip_get_data(gc);
 581        type = bank->type;
 582        drvdata = bank->drvdata;
 583
 584        reg = drvdata->virt_base + bank->pctl_offset +
 585                                        type->reg_offset[PINCFG_TYPE_FUNC];
 586
 587        mask = (1 << type->fld_width[PINCFG_TYPE_FUNC]) - 1;
 588        shift = offset * type->fld_width[PINCFG_TYPE_FUNC];
 589        if (shift >= 32) {
 590                /* Some banks have two config registers */
 591                shift -= 32;
 592                reg += 4;
 593        }
 594
 595        data = readl(reg);
 596        data &= ~(mask << shift);
 597        if (!input)
 598                data |= FUNC_OUTPUT << shift;
 599        writel(data, reg);
 600
 601        return 0;
 602}
 603
 604/* gpiolib gpio_direction_input callback function. */
 605static int samsung_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
 606{
 607        struct samsung_pin_bank *bank = gpiochip_get_data(gc);
 608        unsigned long flags;
 609        int ret;
 610
 611        spin_lock_irqsave(&bank->slock, flags);
 612        ret = samsung_gpio_set_direction(gc, offset, true);
 613        spin_unlock_irqrestore(&bank->slock, flags);
 614        return ret;
 615}
 616
 617/* gpiolib gpio_direction_output callback function. */
 618static int samsung_gpio_direction_output(struct gpio_chip *gc, unsigned offset,
 619                                                        int value)
 620{
 621        struct samsung_pin_bank *bank = gpiochip_get_data(gc);
 622        unsigned long flags;
 623        int ret;
 624
 625        spin_lock_irqsave(&bank->slock, flags);
 626        samsung_gpio_set_value(gc, offset, value);
 627        ret = samsung_gpio_set_direction(gc, offset, false);
 628        spin_unlock_irqrestore(&bank->slock, flags);
 629
 630        return ret;
 631}
 632
 633/*
 634 * gpiolib gpio_to_irq callback function. Creates a mapping between a GPIO pin
 635 * and a virtual IRQ, if not already present.
 636 */
 637static int samsung_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
 638{
 639        struct samsung_pin_bank *bank = gpiochip_get_data(gc);
 640        unsigned int virq;
 641
 642        if (!bank->irq_domain)
 643                return -ENXIO;
 644
 645        virq = irq_create_mapping(bank->irq_domain, offset);
 646
 647        return (virq) ? : -ENXIO;
 648}
 649
 650static struct samsung_pin_group *samsung_pinctrl_create_groups(
 651                                struct device *dev,
 652                                struct samsung_pinctrl_drv_data *drvdata,
 653                                unsigned int *cnt)
 654{
 655        struct pinctrl_desc *ctrldesc = &drvdata->pctl;
 656        struct samsung_pin_group *groups, *grp;
 657        const struct pinctrl_pin_desc *pdesc;
 658        int i;
 659
 660        groups = devm_kzalloc(dev, ctrldesc->npins * sizeof(*groups),
 661                                GFP_KERNEL);
 662        if (!groups)
 663                return ERR_PTR(-EINVAL);
 664        grp = groups;
 665
 666        pdesc = ctrldesc->pins;
 667        for (i = 0; i < ctrldesc->npins; ++i, ++pdesc, ++grp) {
 668                grp->name = pdesc->name;
 669                grp->pins = &pdesc->number;
 670                grp->num_pins = 1;
 671        }
 672
 673        *cnt = ctrldesc->npins;
 674        return groups;
 675}
 676
 677static int samsung_pinctrl_create_function(struct device *dev,
 678                                struct samsung_pinctrl_drv_data *drvdata,
 679                                struct device_node *func_np,
 680                                struct samsung_pmx_func *func)
 681{
 682        int npins;
 683        int ret;
 684        int i;
 685
 686        if (of_property_read_u32(func_np, "samsung,pin-function", &func->val))
 687                return 0;
 688
 689        npins = of_property_count_strings(func_np, "samsung,pins");
 690        if (npins < 1) {
 691                dev_err(dev, "invalid pin list in %s node", func_np->name);
 692                return -EINVAL;
 693        }
 694
 695        func->name = func_np->full_name;
 696
 697        func->groups = devm_kzalloc(dev, npins * sizeof(char *), GFP_KERNEL);
 698        if (!func->groups)
 699                return -ENOMEM;
 700
 701        for (i = 0; i < npins; ++i) {
 702                const char *gname;
 703
 704                ret = of_property_read_string_index(func_np, "samsung,pins",
 705                                                        i, &gname);
 706                if (ret) {
 707                        dev_err(dev,
 708                                "failed to read pin name %d from %s node\n",
 709                                i, func_np->name);
 710                        return ret;
 711                }
 712
 713                func->groups[i] = gname;
 714        }
 715
 716        func->num_groups = npins;
 717        return 1;
 718}
 719
 720static struct samsung_pmx_func *samsung_pinctrl_create_functions(
 721                                struct device *dev,
 722                                struct samsung_pinctrl_drv_data *drvdata,
 723                                unsigned int *cnt)
 724{
 725        struct samsung_pmx_func *functions, *func;
 726        struct device_node *dev_np = dev->of_node;
 727        struct device_node *cfg_np;
 728        unsigned int func_cnt = 0;
 729        int ret;
 730
 731        /*
 732         * Iterate over all the child nodes of the pin controller node
 733         * and create pin groups and pin function lists.
 734         */
 735        for_each_child_of_node(dev_np, cfg_np) {
 736                struct device_node *func_np;
 737
 738                if (!of_get_child_count(cfg_np)) {
 739                        if (!of_find_property(cfg_np,
 740                            "samsung,pin-function", NULL))
 741                                continue;
 742                        ++func_cnt;
 743                        continue;
 744                }
 745
 746                for_each_child_of_node(cfg_np, func_np) {
 747                        if (!of_find_property(func_np,
 748                            "samsung,pin-function", NULL))
 749                                continue;
 750                        ++func_cnt;
 751                }
 752        }
 753
 754        functions = devm_kzalloc(dev, func_cnt * sizeof(*functions),
 755                                        GFP_KERNEL);
 756        if (!functions) {
 757                dev_err(dev, "failed to allocate memory for function list\n");
 758                return ERR_PTR(-EINVAL);
 759        }
 760        func = functions;
 761
 762        /*
 763         * Iterate over all the child nodes of the pin controller node
 764         * and create pin groups and pin function lists.
 765         */
 766        func_cnt = 0;
 767        for_each_child_of_node(dev_np, cfg_np) {
 768                struct device_node *func_np;
 769
 770                if (!of_get_child_count(cfg_np)) {
 771                        ret = samsung_pinctrl_create_function(dev, drvdata,
 772                                                        cfg_np, func);
 773                        if (ret < 0)
 774                                return ERR_PTR(ret);
 775                        if (ret > 0) {
 776                                ++func;
 777                                ++func_cnt;
 778                        }
 779                        continue;
 780                }
 781
 782                for_each_child_of_node(cfg_np, func_np) {
 783                        ret = samsung_pinctrl_create_function(dev, drvdata,
 784                                                func_np, func);
 785                        if (ret < 0)
 786                                return ERR_PTR(ret);
 787                        if (ret > 0) {
 788                                ++func;
 789                                ++func_cnt;
 790                        }
 791                }
 792        }
 793
 794        *cnt = func_cnt;
 795        return functions;
 796}
 797
 798/*
 799 * Parse the information about all the available pin groups and pin functions
 800 * from device node of the pin-controller. A pin group is formed with all
 801 * the pins listed in the "samsung,pins" property.
 802 */
 803
 804static int samsung_pinctrl_parse_dt(struct platform_device *pdev,
 805                                    struct samsung_pinctrl_drv_data *drvdata)
 806{
 807        struct device *dev = &pdev->dev;
 808        struct samsung_pin_group *groups;
 809        struct samsung_pmx_func *functions;
 810        unsigned int grp_cnt = 0, func_cnt = 0;
 811
 812        groups = samsung_pinctrl_create_groups(dev, drvdata, &grp_cnt);
 813        if (IS_ERR(groups)) {
 814                dev_err(dev, "failed to parse pin groups\n");
 815                return PTR_ERR(groups);
 816        }
 817
 818        functions = samsung_pinctrl_create_functions(dev, drvdata, &func_cnt);
 819        if (IS_ERR(functions)) {
 820                dev_err(dev, "failed to parse pin functions\n");
 821                return PTR_ERR(functions);
 822        }
 823
 824        drvdata->pin_groups = groups;
 825        drvdata->nr_groups = grp_cnt;
 826        drvdata->pmx_functions = functions;
 827        drvdata->nr_functions = func_cnt;
 828
 829        return 0;
 830}
 831
 832/* register the pinctrl interface with the pinctrl subsystem */
 833static int samsung_pinctrl_register(struct platform_device *pdev,
 834                                    struct samsung_pinctrl_drv_data *drvdata)
 835{
 836        struct pinctrl_desc *ctrldesc = &drvdata->pctl;
 837        struct pinctrl_pin_desc *pindesc, *pdesc;
 838        struct samsung_pin_bank *pin_bank;
 839        char *pin_names;
 840        int pin, bank, ret;
 841
 842        ctrldesc->name = "samsung-pinctrl";
 843        ctrldesc->owner = THIS_MODULE;
 844        ctrldesc->pctlops = &samsung_pctrl_ops;
 845        ctrldesc->pmxops = &samsung_pinmux_ops;
 846        ctrldesc->confops = &samsung_pinconf_ops;
 847
 848        pindesc = devm_kzalloc(&pdev->dev, sizeof(*pindesc) *
 849                        drvdata->nr_pins, GFP_KERNEL);
 850        if (!pindesc) {
 851                dev_err(&pdev->dev, "mem alloc for pin descriptors failed\n");
 852                return -ENOMEM;
 853        }
 854        ctrldesc->pins = pindesc;
 855        ctrldesc->npins = drvdata->nr_pins;
 856
 857        /* dynamically populate the pin number and pin name for pindesc */
 858        for (pin = 0, pdesc = pindesc; pin < ctrldesc->npins; pin++, pdesc++)
 859                pdesc->number = pin + drvdata->pin_base;
 860
 861        /*
 862         * allocate space for storing the dynamically generated names for all
 863         * the pins which belong to this pin-controller.
 864         */
 865        pin_names = devm_kzalloc(&pdev->dev, sizeof(char) * PIN_NAME_LENGTH *
 866                                        drvdata->nr_pins, GFP_KERNEL);
 867        if (!pin_names) {
 868                dev_err(&pdev->dev, "mem alloc for pin names failed\n");
 869                return -ENOMEM;
 870        }
 871
 872        /* for each pin, the name of the pin is pin-bank name + pin number */
 873        for (bank = 0; bank < drvdata->nr_banks; bank++) {
 874                pin_bank = &drvdata->pin_banks[bank];
 875                for (pin = 0; pin < pin_bank->nr_pins; pin++) {
 876                        sprintf(pin_names, "%s-%d", pin_bank->name, pin);
 877                        pdesc = pindesc + pin_bank->pin_base + pin;
 878                        pdesc->name = pin_names;
 879                        pin_names += PIN_NAME_LENGTH;
 880                }
 881        }
 882
 883        ret = samsung_pinctrl_parse_dt(pdev, drvdata);
 884        if (ret)
 885                return ret;
 886
 887        drvdata->pctl_dev = devm_pinctrl_register(&pdev->dev, ctrldesc,
 888                                                  drvdata);
 889        if (IS_ERR(drvdata->pctl_dev)) {
 890                dev_err(&pdev->dev, "could not register pinctrl driver\n");
 891                return PTR_ERR(drvdata->pctl_dev);
 892        }
 893
 894        for (bank = 0; bank < drvdata->nr_banks; ++bank) {
 895                pin_bank = &drvdata->pin_banks[bank];
 896                pin_bank->grange.name = pin_bank->name;
 897                pin_bank->grange.id = bank;
 898                pin_bank->grange.pin_base = drvdata->pin_base
 899                                                + pin_bank->pin_base;
 900                pin_bank->grange.base = pin_bank->gpio_chip.base;
 901                pin_bank->grange.npins = pin_bank->gpio_chip.ngpio;
 902                pin_bank->grange.gc = &pin_bank->gpio_chip;
 903                pinctrl_add_gpio_range(drvdata->pctl_dev, &pin_bank->grange);
 904        }
 905
 906        return 0;
 907}
 908
 909static const struct gpio_chip samsung_gpiolib_chip = {
 910        .request = gpiochip_generic_request,
 911        .free = gpiochip_generic_free,
 912        .set = samsung_gpio_set,
 913        .get = samsung_gpio_get,
 914        .direction_input = samsung_gpio_direction_input,
 915        .direction_output = samsung_gpio_direction_output,
 916        .to_irq = samsung_gpio_to_irq,
 917        .owner = THIS_MODULE,
 918};
 919
 920/* register the gpiolib interface with the gpiolib subsystem */
 921static int samsung_gpiolib_register(struct platform_device *pdev,
 922                                    struct samsung_pinctrl_drv_data *drvdata)
 923{
 924        struct samsung_pin_bank *bank = drvdata->pin_banks;
 925        struct gpio_chip *gc;
 926        int ret;
 927        int i;
 928
 929        for (i = 0; i < drvdata->nr_banks; ++i, ++bank) {
 930                bank->gpio_chip = samsung_gpiolib_chip;
 931
 932                gc = &bank->gpio_chip;
 933                gc->base = drvdata->pin_base + bank->pin_base;
 934                gc->ngpio = bank->nr_pins;
 935                gc->parent = &pdev->dev;
 936                gc->of_node = bank->of_node;
 937                gc->label = bank->name;
 938
 939                ret = gpiochip_add_data(gc, bank);
 940                if (ret) {
 941                        dev_err(&pdev->dev, "failed to register gpio_chip %s, error code: %d\n",
 942                                                        gc->label, ret);
 943                        goto fail;
 944                }
 945        }
 946
 947        return 0;
 948
 949fail:
 950        for (--i, --bank; i >= 0; --i, --bank)
 951                gpiochip_remove(&bank->gpio_chip);
 952        return ret;
 953}
 954
 955/* unregister the gpiolib interface with the gpiolib subsystem */
 956static int samsung_gpiolib_unregister(struct platform_device *pdev,
 957                                      struct samsung_pinctrl_drv_data *drvdata)
 958{
 959        struct samsung_pin_bank *bank = drvdata->pin_banks;
 960        int i;
 961
 962        for (i = 0; i < drvdata->nr_banks; ++i, ++bank)
 963                gpiochip_remove(&bank->gpio_chip);
 964
 965        return 0;
 966}
 967
 968static const struct of_device_id samsung_pinctrl_dt_match[];
 969
 970/* retrieve the soc specific data */
 971static const struct samsung_pin_ctrl *
 972samsung_pinctrl_get_soc_data(struct samsung_pinctrl_drv_data *d,
 973                             struct platform_device *pdev)
 974{
 975        int id;
 976        const struct of_device_id *match;
 977        struct device_node *node = pdev->dev.of_node;
 978        struct device_node *np;
 979        const struct samsung_pin_bank_data *bdata;
 980        const struct samsung_pin_ctrl *ctrl;
 981        struct samsung_pin_bank *bank;
 982        int i;
 983
 984        id = of_alias_get_id(node, "pinctrl");
 985        if (id < 0) {
 986                dev_err(&pdev->dev, "failed to get alias id\n");
 987                return ERR_PTR(-ENOENT);
 988        }
 989        match = of_match_node(samsung_pinctrl_dt_match, node);
 990        ctrl = (struct samsung_pin_ctrl *)match->data + id;
 991
 992        d->suspend = ctrl->suspend;
 993        d->resume = ctrl->resume;
 994        d->nr_banks = ctrl->nr_banks;
 995        d->pin_banks = devm_kcalloc(&pdev->dev, d->nr_banks,
 996                                        sizeof(*d->pin_banks), GFP_KERNEL);
 997        if (!d->pin_banks)
 998                return ERR_PTR(-ENOMEM);
 999
1000        bank = d->pin_banks;
1001        bdata = ctrl->pin_banks;
1002        for (i = 0; i < ctrl->nr_banks; ++i, ++bdata, ++bank) {
1003                bank->type = bdata->type;
1004                bank->pctl_offset = bdata->pctl_offset;
1005                bank->nr_pins = bdata->nr_pins;
1006                bank->eint_func = bdata->eint_func;
1007                bank->eint_type = bdata->eint_type;
1008                bank->eint_mask = bdata->eint_mask;
1009                bank->eint_offset = bdata->eint_offset;
1010                bank->name = bdata->name;
1011
1012                spin_lock_init(&bank->slock);
1013                bank->drvdata = d;
1014                bank->pin_base = d->nr_pins;
1015                d->nr_pins += bank->nr_pins;
1016        }
1017
1018        for_each_child_of_node(node, np) {
1019                if (!of_find_property(np, "gpio-controller", NULL))
1020                        continue;
1021                bank = d->pin_banks;
1022                for (i = 0; i < d->nr_banks; ++i, ++bank) {
1023                        if (!strcmp(bank->name, np->name)) {
1024                                bank->of_node = np;
1025                                break;
1026                        }
1027                }
1028        }
1029
1030        d->pin_base = pin_base;
1031        pin_base += d->nr_pins;
1032
1033        return ctrl;
1034}
1035
1036static int samsung_pinctrl_probe(struct platform_device *pdev)
1037{
1038        struct samsung_pinctrl_drv_data *drvdata;
1039        const struct samsung_pin_ctrl *ctrl;
1040        struct device *dev = &pdev->dev;
1041        struct resource *res;
1042        int ret;
1043
1044        drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
1045        if (!drvdata)
1046                return -ENOMEM;
1047
1048        ctrl = samsung_pinctrl_get_soc_data(drvdata, pdev);
1049        if (IS_ERR(ctrl)) {
1050                dev_err(&pdev->dev, "driver data not available\n");
1051                return PTR_ERR(ctrl);
1052        }
1053        drvdata->dev = dev;
1054
1055        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1056        drvdata->virt_base = devm_ioremap_resource(&pdev->dev, res);
1057        if (IS_ERR(drvdata->virt_base))
1058                return PTR_ERR(drvdata->virt_base);
1059
1060        res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
1061        if (res)
1062                drvdata->irq = res->start;
1063
1064        ret = samsung_gpiolib_register(pdev, drvdata);
1065        if (ret)
1066                return ret;
1067
1068        ret = samsung_pinctrl_register(pdev, drvdata);
1069        if (ret) {
1070                samsung_gpiolib_unregister(pdev, drvdata);
1071                return ret;
1072        }
1073
1074        if (ctrl->eint_gpio_init)
1075                ctrl->eint_gpio_init(drvdata);
1076        if (ctrl->eint_wkup_init)
1077                ctrl->eint_wkup_init(drvdata);
1078
1079        platform_set_drvdata(pdev, drvdata);
1080
1081        /* Add to the global list */
1082        list_add_tail(&drvdata->node, &drvdata_list);
1083
1084        return 0;
1085}
1086
1087#ifdef CONFIG_PM
1088
1089/**
1090 * samsung_pinctrl_suspend_dev - save pinctrl state for suspend for a device
1091 *
1092 * Save data for all banks handled by this device.
1093 */
1094static void samsung_pinctrl_suspend_dev(
1095        struct samsung_pinctrl_drv_data *drvdata)
1096{
1097        void __iomem *virt_base = drvdata->virt_base;
1098        int i;
1099
1100        for (i = 0; i < drvdata->nr_banks; i++) {
1101                struct samsung_pin_bank *bank = &drvdata->pin_banks[i];
1102                void __iomem *reg = virt_base + bank->pctl_offset;
1103                const u8 *offs = bank->type->reg_offset;
1104                const u8 *widths = bank->type->fld_width;
1105                enum pincfg_type type;
1106
1107                /* Registers without a powerdown config aren't lost */
1108                if (!widths[PINCFG_TYPE_CON_PDN])
1109                        continue;
1110
1111                for (type = 0; type < PINCFG_TYPE_NUM; type++)
1112                        if (widths[type])
1113                                bank->pm_save[type] = readl(reg + offs[type]);
1114
1115                if (widths[PINCFG_TYPE_FUNC] * bank->nr_pins > 32) {
1116                        /* Some banks have two config registers */
1117                        bank->pm_save[PINCFG_TYPE_NUM] =
1118                                readl(reg + offs[PINCFG_TYPE_FUNC] + 4);
1119                        pr_debug("Save %s @ %p (con %#010x %08x)\n",
1120                                 bank->name, reg,
1121                                 bank->pm_save[PINCFG_TYPE_FUNC],
1122                                 bank->pm_save[PINCFG_TYPE_NUM]);
1123                } else {
1124                        pr_debug("Save %s @ %p (con %#010x)\n", bank->name,
1125                                 reg, bank->pm_save[PINCFG_TYPE_FUNC]);
1126                }
1127        }
1128
1129        if (drvdata->suspend)
1130                drvdata->suspend(drvdata);
1131}
1132
1133/**
1134 * samsung_pinctrl_resume_dev - restore pinctrl state from suspend for a device
1135 *
1136 * Restore one of the banks that was saved during suspend.
1137 *
1138 * We don't bother doing anything complicated to avoid glitching lines since
1139 * we're called before pad retention is turned off.
1140 */
1141static void samsung_pinctrl_resume_dev(struct samsung_pinctrl_drv_data *drvdata)
1142{
1143        void __iomem *virt_base = drvdata->virt_base;
1144        int i;
1145
1146        if (drvdata->resume)
1147                drvdata->resume(drvdata);
1148
1149        for (i = 0; i < drvdata->nr_banks; i++) {
1150                struct samsung_pin_bank *bank = &drvdata->pin_banks[i];
1151                void __iomem *reg = virt_base + bank->pctl_offset;
1152                const u8 *offs = bank->type->reg_offset;
1153                const u8 *widths = bank->type->fld_width;
1154                enum pincfg_type type;
1155
1156                /* Registers without a powerdown config aren't lost */
1157                if (!widths[PINCFG_TYPE_CON_PDN])
1158                        continue;
1159
1160                if (widths[PINCFG_TYPE_FUNC] * bank->nr_pins > 32) {
1161                        /* Some banks have two config registers */
1162                        pr_debug("%s @ %p (con %#010x %08x => %#010x %08x)\n",
1163                                 bank->name, reg,
1164                                 readl(reg + offs[PINCFG_TYPE_FUNC]),
1165                                 readl(reg + offs[PINCFG_TYPE_FUNC] + 4),
1166                                 bank->pm_save[PINCFG_TYPE_FUNC],
1167                                 bank->pm_save[PINCFG_TYPE_NUM]);
1168                        writel(bank->pm_save[PINCFG_TYPE_NUM],
1169                               reg + offs[PINCFG_TYPE_FUNC] + 4);
1170                } else {
1171                        pr_debug("%s @ %p (con %#010x => %#010x)\n", bank->name,
1172                                 reg, readl(reg + offs[PINCFG_TYPE_FUNC]),
1173                                 bank->pm_save[PINCFG_TYPE_FUNC]);
1174                }
1175                for (type = 0; type < PINCFG_TYPE_NUM; type++)
1176                        if (widths[type])
1177                                writel(bank->pm_save[type], reg + offs[type]);
1178        }
1179}
1180
1181/**
1182 * samsung_pinctrl_suspend - save pinctrl state for suspend
1183 *
1184 * Save data for all banks across all devices.
1185 */
1186static int samsung_pinctrl_suspend(void)
1187{
1188        struct samsung_pinctrl_drv_data *drvdata;
1189
1190        list_for_each_entry(drvdata, &drvdata_list, node) {
1191                samsung_pinctrl_suspend_dev(drvdata);
1192        }
1193
1194        return 0;
1195}
1196
1197/**
1198 * samsung_pinctrl_resume - restore pinctrl state for suspend
1199 *
1200 * Restore data for all banks across all devices.
1201 */
1202static void samsung_pinctrl_resume(void)
1203{
1204        struct samsung_pinctrl_drv_data *drvdata;
1205
1206        list_for_each_entry_reverse(drvdata, &drvdata_list, node) {
1207                samsung_pinctrl_resume_dev(drvdata);
1208        }
1209}
1210
1211#else
1212#define samsung_pinctrl_suspend         NULL
1213#define samsung_pinctrl_resume          NULL
1214#endif
1215
1216static struct syscore_ops samsung_pinctrl_syscore_ops = {
1217        .suspend        = samsung_pinctrl_suspend,
1218        .resume         = samsung_pinctrl_resume,
1219};
1220
1221static const struct of_device_id samsung_pinctrl_dt_match[] = {
1222#ifdef CONFIG_PINCTRL_EXYNOS
1223        { .compatible = "samsung,exynos3250-pinctrl",
1224                .data = (void *)exynos3250_pin_ctrl },
1225        { .compatible = "samsung,exynos4210-pinctrl",
1226                .data = (void *)exynos4210_pin_ctrl },
1227        { .compatible = "samsung,exynos4x12-pinctrl",
1228                .data = (void *)exynos4x12_pin_ctrl },
1229        { .compatible = "samsung,exynos4415-pinctrl",
1230                .data = (void *)exynos4415_pin_ctrl },
1231        { .compatible = "samsung,exynos5250-pinctrl",
1232                .data = (void *)exynos5250_pin_ctrl },
1233        { .compatible = "samsung,exynos5260-pinctrl",
1234                .data = (void *)exynos5260_pin_ctrl },
1235        { .compatible = "samsung,exynos5410-pinctrl",
1236                .data = (void *)exynos5410_pin_ctrl },
1237        { .compatible = "samsung,exynos5420-pinctrl",
1238                .data = (void *)exynos5420_pin_ctrl },
1239        { .compatible = "samsung,exynos5433-pinctrl",
1240                .data = (void *)exynos5433_pin_ctrl },
1241        { .compatible = "samsung,s5pv210-pinctrl",
1242                .data = (void *)s5pv210_pin_ctrl },
1243        { .compatible = "samsung,exynos7-pinctrl",
1244                .data = (void *)exynos7_pin_ctrl },
1245#endif
1246#ifdef CONFIG_PINCTRL_S3C64XX
1247        { .compatible = "samsung,s3c64xx-pinctrl",
1248                .data = s3c64xx_pin_ctrl },
1249#endif
1250#ifdef CONFIG_PINCTRL_S3C24XX
1251        { .compatible = "samsung,s3c2412-pinctrl",
1252                .data = s3c2412_pin_ctrl },
1253        { .compatible = "samsung,s3c2416-pinctrl",
1254                .data = s3c2416_pin_ctrl },
1255        { .compatible = "samsung,s3c2440-pinctrl",
1256                .data = s3c2440_pin_ctrl },
1257        { .compatible = "samsung,s3c2450-pinctrl",
1258                .data = s3c2450_pin_ctrl },
1259#endif
1260        {},
1261};
1262MODULE_DEVICE_TABLE(of, samsung_pinctrl_dt_match);
1263
1264static struct platform_driver samsung_pinctrl_driver = {
1265        .probe          = samsung_pinctrl_probe,
1266        .driver = {
1267                .name   = "samsung-pinctrl",
1268                .of_match_table = samsung_pinctrl_dt_match,
1269                .suppress_bind_attrs = true,
1270        },
1271};
1272
1273static int __init samsung_pinctrl_drv_register(void)
1274{
1275        /*
1276         * Register syscore ops for save/restore of registers across suspend.
1277         * It's important to ensure that this driver is running at an earlier
1278         * initcall level than any arch-specific init calls that install syscore
1279         * ops that turn off pad retention (like exynos_pm_resume).
1280         */
1281        register_syscore_ops(&samsung_pinctrl_syscore_ops);
1282
1283        return platform_driver_register(&samsung_pinctrl_driver);
1284}
1285postcore_initcall(samsung_pinctrl_drv_register);
1286
1287static void __exit samsung_pinctrl_drv_unregister(void)
1288{
1289        platform_driver_unregister(&samsung_pinctrl_driver);
1290}
1291module_exit(samsung_pinctrl_drv_unregister);
1292
1293MODULE_AUTHOR("Thomas Abraham <thomas.ab@samsung.com>");
1294MODULE_DESCRIPTION("Samsung pinctrl driver");
1295MODULE_LICENSE("GPL v2");
1296