linux/drivers/pinctrl/vt8500/pinctrl-wmt.c
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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Pinctrl driver for the Wondermedia SoC's
   4 *
   5 * Copyright (c) 2013 Tony Prisk <linux@prisktech.co.nz>
   6 */
   7
   8#include <linux/err.h>
   9#include <linux/gpio/driver.h>
  10#include <linux/interrupt.h>
  11#include <linux/io.h>
  12#include <linux/irq.h>
  13#include <linux/of.h>
  14#include <linux/of_irq.h>
  15#include <linux/pinctrl/consumer.h>
  16#include <linux/pinctrl/machine.h>
  17#include <linux/pinctrl/pinconf.h>
  18#include <linux/pinctrl/pinconf-generic.h>
  19#include <linux/pinctrl/pinctrl.h>
  20#include <linux/pinctrl/pinmux.h>
  21#include <linux/platform_device.h>
  22#include <linux/slab.h>
  23
  24#include "pinctrl-wmt.h"
  25
  26static inline void wmt_setbits(struct wmt_pinctrl_data *data, u32 reg,
  27                                 u32 mask)
  28{
  29        u32 val;
  30
  31        val = readl_relaxed(data->base + reg);
  32        val |= mask;
  33        writel_relaxed(val, data->base + reg);
  34}
  35
  36static inline void wmt_clearbits(struct wmt_pinctrl_data *data, u32 reg,
  37                                   u32 mask)
  38{
  39        u32 val;
  40
  41        val = readl_relaxed(data->base + reg);
  42        val &= ~mask;
  43        writel_relaxed(val, data->base + reg);
  44}
  45
  46enum wmt_func_sel {
  47        WMT_FSEL_GPIO_IN = 0,
  48        WMT_FSEL_GPIO_OUT = 1,
  49        WMT_FSEL_ALT = 2,
  50        WMT_FSEL_COUNT = 3,
  51};
  52
  53static const char * const wmt_functions[WMT_FSEL_COUNT] = {
  54        [WMT_FSEL_GPIO_IN] = "gpio_in",
  55        [WMT_FSEL_GPIO_OUT] = "gpio_out",
  56        [WMT_FSEL_ALT] = "alt",
  57};
  58
  59static int wmt_pmx_get_functions_count(struct pinctrl_dev *pctldev)
  60{
  61        return WMT_FSEL_COUNT;
  62}
  63
  64static const char *wmt_pmx_get_function_name(struct pinctrl_dev *pctldev,
  65                                             unsigned selector)
  66{
  67        return wmt_functions[selector];
  68}
  69
  70static int wmt_pmx_get_function_groups(struct pinctrl_dev *pctldev,
  71                                       unsigned selector,
  72                                       const char * const **groups,
  73                                       unsigned * const num_groups)
  74{
  75        struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
  76
  77        /* every pin does every function */
  78        *groups = data->groups;
  79        *num_groups = data->ngroups;
  80
  81        return 0;
  82}
  83
  84static int wmt_set_pinmux(struct wmt_pinctrl_data *data, unsigned func,
  85                          unsigned pin)
  86{
  87        u32 bank = WMT_BANK_FROM_PIN(pin);
  88        u32 bit = WMT_BIT_FROM_PIN(pin);
  89        u32 reg_en = data->banks[bank].reg_en;
  90        u32 reg_dir = data->banks[bank].reg_dir;
  91
  92        if (reg_dir == NO_REG) {
  93                dev_err(data->dev, "pin:%d no direction register defined\n",
  94                        pin);
  95                return -EINVAL;
  96        }
  97
  98        /*
  99         * If reg_en == NO_REG, we assume it is a dedicated GPIO and cannot be
 100         * disabled (as on VT8500) and that no alternate function is available.
 101         */
 102        switch (func) {
 103        case WMT_FSEL_GPIO_IN:
 104                if (reg_en != NO_REG)
 105                        wmt_setbits(data, reg_en, BIT(bit));
 106                wmt_clearbits(data, reg_dir, BIT(bit));
 107                break;
 108        case WMT_FSEL_GPIO_OUT:
 109                if (reg_en != NO_REG)
 110                        wmt_setbits(data, reg_en, BIT(bit));
 111                wmt_setbits(data, reg_dir, BIT(bit));
 112                break;
 113        case WMT_FSEL_ALT:
 114                if (reg_en == NO_REG) {
 115                        dev_err(data->dev, "pin:%d no alt function available\n",
 116                                pin);
 117                        return -EINVAL;
 118                }
 119                wmt_clearbits(data, reg_en, BIT(bit));
 120        }
 121
 122        return 0;
 123}
 124
 125static int wmt_pmx_set_mux(struct pinctrl_dev *pctldev,
 126                           unsigned func_selector,
 127                           unsigned group_selector)
 128{
 129        struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
 130        u32 pinnum = data->pins[group_selector].number;
 131
 132        return wmt_set_pinmux(data, func_selector, pinnum);
 133}
 134
 135static void wmt_pmx_gpio_disable_free(struct pinctrl_dev *pctldev,
 136                                      struct pinctrl_gpio_range *range,
 137                                      unsigned offset)
 138{
 139        struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
 140
 141        /* disable by setting GPIO_IN */
 142        wmt_set_pinmux(data, WMT_FSEL_GPIO_IN, offset);
 143}
 144
 145static int wmt_pmx_gpio_set_direction(struct pinctrl_dev *pctldev,
 146                                      struct pinctrl_gpio_range *range,
 147                                      unsigned offset,
 148                                      bool input)
 149{
 150        struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
 151
 152        wmt_set_pinmux(data, (input ? WMT_FSEL_GPIO_IN : WMT_FSEL_GPIO_OUT),
 153                       offset);
 154
 155        return 0;
 156}
 157
 158static const struct pinmux_ops wmt_pinmux_ops = {
 159        .get_functions_count = wmt_pmx_get_functions_count,
 160        .get_function_name = wmt_pmx_get_function_name,
 161        .get_function_groups = wmt_pmx_get_function_groups,
 162        .set_mux = wmt_pmx_set_mux,
 163        .gpio_disable_free = wmt_pmx_gpio_disable_free,
 164        .gpio_set_direction = wmt_pmx_gpio_set_direction,
 165};
 166
 167static int wmt_get_groups_count(struct pinctrl_dev *pctldev)
 168{
 169        struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
 170
 171        return data->ngroups;
 172}
 173
 174static const char *wmt_get_group_name(struct pinctrl_dev *pctldev,
 175                                      unsigned selector)
 176{
 177        struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
 178
 179        return data->groups[selector];
 180}
 181
 182static int wmt_get_group_pins(struct pinctrl_dev *pctldev,
 183                              unsigned selector,
 184                              const unsigned **pins,
 185                              unsigned *num_pins)
 186{
 187        struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
 188
 189        *pins = &data->pins[selector].number;
 190        *num_pins = 1;
 191
 192        return 0;
 193}
 194
 195static int wmt_pctl_find_group_by_pin(struct wmt_pinctrl_data *data, u32 pin)
 196{
 197        int i;
 198
 199        for (i = 0; i < data->npins; i++) {
 200                if (data->pins[i].number == pin)
 201                        return i;
 202        }
 203
 204        return -EINVAL;
 205}
 206
 207static int wmt_pctl_dt_node_to_map_func(struct wmt_pinctrl_data *data,
 208                                        struct device_node *np,
 209                                        u32 pin, u32 fnum,
 210                                        struct pinctrl_map **maps)
 211{
 212        int group;
 213        struct pinctrl_map *map = *maps;
 214
 215        if (fnum >= ARRAY_SIZE(wmt_functions)) {
 216                dev_err(data->dev, "invalid wm,function %d\n", fnum);
 217                return -EINVAL;
 218        }
 219
 220        group = wmt_pctl_find_group_by_pin(data, pin);
 221        if (group < 0) {
 222                dev_err(data->dev, "unable to match pin %d to group\n", pin);
 223                return group;
 224        }
 225
 226        map->type = PIN_MAP_TYPE_MUX_GROUP;
 227        map->data.mux.group = data->groups[group];
 228        map->data.mux.function = wmt_functions[fnum];
 229        (*maps)++;
 230
 231        return 0;
 232}
 233
 234static int wmt_pctl_dt_node_to_map_pull(struct wmt_pinctrl_data *data,
 235                                        struct device_node *np,
 236                                        u32 pin, u32 pull,
 237                                        struct pinctrl_map **maps)
 238{
 239        int group;
 240        unsigned long *configs;
 241        struct pinctrl_map *map = *maps;
 242
 243        if (pull > 2) {
 244                dev_err(data->dev, "invalid wm,pull %d\n", pull);
 245                return -EINVAL;
 246        }
 247
 248        group = wmt_pctl_find_group_by_pin(data, pin);
 249        if (group < 0) {
 250                dev_err(data->dev, "unable to match pin %d to group\n", pin);
 251                return group;
 252        }
 253
 254        configs = kzalloc(sizeof(*configs), GFP_KERNEL);
 255        if (!configs)
 256                return -ENOMEM;
 257
 258        switch (pull) {
 259        case 0:
 260                configs[0] = PIN_CONFIG_BIAS_DISABLE;
 261                break;
 262        case 1:
 263                configs[0] = PIN_CONFIG_BIAS_PULL_DOWN;
 264                break;
 265        case 2:
 266                configs[0] = PIN_CONFIG_BIAS_PULL_UP;
 267                break;
 268        default:
 269                configs[0] = PIN_CONFIG_BIAS_DISABLE;
 270                dev_err(data->dev, "invalid pull state %d - disabling\n", pull);
 271        }
 272
 273        map->type = PIN_MAP_TYPE_CONFIGS_PIN;
 274        map->data.configs.group_or_pin = data->groups[group];
 275        map->data.configs.configs = configs;
 276        map->data.configs.num_configs = 1;
 277        (*maps)++;
 278
 279        return 0;
 280}
 281
 282static void wmt_pctl_dt_free_map(struct pinctrl_dev *pctldev,
 283                                 struct pinctrl_map *maps,
 284                                 unsigned num_maps)
 285{
 286        int i;
 287
 288        for (i = 0; i < num_maps; i++)
 289                if (maps[i].type == PIN_MAP_TYPE_CONFIGS_PIN)
 290                        kfree(maps[i].data.configs.configs);
 291
 292        kfree(maps);
 293}
 294
 295static int wmt_pctl_dt_node_to_map(struct pinctrl_dev *pctldev,
 296                                   struct device_node *np,
 297                                   struct pinctrl_map **map,
 298                                   unsigned *num_maps)
 299{
 300        struct pinctrl_map *maps, *cur_map;
 301        struct property *pins, *funcs, *pulls;
 302        u32 pin, func, pull;
 303        int num_pins, num_funcs, num_pulls, maps_per_pin;
 304        int i, err;
 305        struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
 306
 307        pins = of_find_property(np, "wm,pins", NULL);
 308        if (!pins) {
 309                dev_err(data->dev, "missing wmt,pins property\n");
 310                return -EINVAL;
 311        }
 312
 313        funcs = of_find_property(np, "wm,function", NULL);
 314        pulls = of_find_property(np, "wm,pull", NULL);
 315
 316        if (!funcs && !pulls) {
 317                dev_err(data->dev, "neither wm,function nor wm,pull specified\n");
 318                return -EINVAL;
 319        }
 320
 321        /*
 322         * The following lines calculate how many values are defined for each
 323         * of the properties.
 324         */
 325        num_pins = pins->length / sizeof(u32);
 326        num_funcs = funcs ? (funcs->length / sizeof(u32)) : 0;
 327        num_pulls = pulls ? (pulls->length / sizeof(u32)) : 0;
 328
 329        if (num_funcs > 1 && num_funcs != num_pins) {
 330                dev_err(data->dev, "wm,function must have 1 or %d entries\n",
 331                        num_pins);
 332                return -EINVAL;
 333        }
 334
 335        if (num_pulls > 1 && num_pulls != num_pins) {
 336                dev_err(data->dev, "wm,pull must have 1 or %d entries\n",
 337                        num_pins);
 338                return -EINVAL;
 339        }
 340
 341        maps_per_pin = 0;
 342        if (num_funcs)
 343                maps_per_pin++;
 344        if (num_pulls)
 345                maps_per_pin++;
 346
 347        cur_map = maps = kcalloc(num_pins * maps_per_pin, sizeof(*maps),
 348                                 GFP_KERNEL);
 349        if (!maps)
 350                return -ENOMEM;
 351
 352        for (i = 0; i < num_pins; i++) {
 353                err = of_property_read_u32_index(np, "wm,pins", i, &pin);
 354                if (err)
 355                        goto fail;
 356
 357                if (pin >= (data->nbanks * 32)) {
 358                        dev_err(data->dev, "invalid wm,pins value\n");
 359                        err = -EINVAL;
 360                        goto fail;
 361                }
 362
 363                if (num_funcs) {
 364                        err = of_property_read_u32_index(np, "wm,function",
 365                                                (num_funcs > 1 ? i : 0), &func);
 366                        if (err)
 367                                goto fail;
 368
 369                        err = wmt_pctl_dt_node_to_map_func(data, np, pin, func,
 370                                                           &cur_map);
 371                        if (err)
 372                                goto fail;
 373                }
 374
 375                if (num_pulls) {
 376                        err = of_property_read_u32_index(np, "wm,pull",
 377                                                (num_pulls > 1 ? i : 0), &pull);
 378                        if (err)
 379                                goto fail;
 380
 381                        err = wmt_pctl_dt_node_to_map_pull(data, np, pin, pull,
 382                                                           &cur_map);
 383                        if (err)
 384                                goto fail;
 385                }
 386        }
 387        *map = maps;
 388        *num_maps = num_pins * maps_per_pin;
 389        return 0;
 390
 391/*
 392 * The fail path removes any maps that have been allocated. The fail path is
 393 * only called from code after maps has been kzalloc'd. It is also safe to
 394 * pass 'num_pins * maps_per_pin' as the map count even though we probably
 395 * failed before all the mappings were read as all maps are allocated at once,
 396 * and configs are only allocated for .type = PIN_MAP_TYPE_CONFIGS_PIN - there
 397 * is no failpath where a config can be allocated without .type being set.
 398 */
 399fail:
 400        wmt_pctl_dt_free_map(pctldev, maps, num_pins * maps_per_pin);
 401        return err;
 402}
 403
 404static const struct pinctrl_ops wmt_pctl_ops = {
 405        .get_groups_count = wmt_get_groups_count,
 406        .get_group_name = wmt_get_group_name,
 407        .get_group_pins = wmt_get_group_pins,
 408        .dt_node_to_map = wmt_pctl_dt_node_to_map,
 409        .dt_free_map = wmt_pctl_dt_free_map,
 410};
 411
 412static int wmt_pinconf_get(struct pinctrl_dev *pctldev, unsigned pin,
 413                           unsigned long *config)
 414{
 415        return -ENOTSUPP;
 416}
 417
 418static int wmt_pinconf_set(struct pinctrl_dev *pctldev, unsigned pin,
 419                           unsigned long *configs, unsigned num_configs)
 420{
 421        struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
 422        enum pin_config_param param;
 423        u32 arg;
 424        u32 bank = WMT_BANK_FROM_PIN(pin);
 425        u32 bit = WMT_BIT_FROM_PIN(pin);
 426        u32 reg_pull_en = data->banks[bank].reg_pull_en;
 427        u32 reg_pull_cfg = data->banks[bank].reg_pull_cfg;
 428        int i;
 429
 430        if ((reg_pull_en == NO_REG) || (reg_pull_cfg == NO_REG)) {
 431                dev_err(data->dev, "bias functions not supported on pin %d\n",
 432                        pin);
 433                return -EINVAL;
 434        }
 435
 436        for (i = 0; i < num_configs; i++) {
 437                param = pinconf_to_config_param(configs[i]);
 438                arg = pinconf_to_config_argument(configs[i]);
 439
 440                if ((param == PIN_CONFIG_BIAS_PULL_DOWN) ||
 441                    (param == PIN_CONFIG_BIAS_PULL_UP)) {
 442                        if (arg == 0)
 443                                param = PIN_CONFIG_BIAS_DISABLE;
 444                }
 445
 446                switch (param) {
 447                case PIN_CONFIG_BIAS_DISABLE:
 448                        wmt_clearbits(data, reg_pull_en, BIT(bit));
 449                        break;
 450                case PIN_CONFIG_BIAS_PULL_DOWN:
 451                        wmt_clearbits(data, reg_pull_cfg, BIT(bit));
 452                        wmt_setbits(data, reg_pull_en, BIT(bit));
 453                        break;
 454                case PIN_CONFIG_BIAS_PULL_UP:
 455                        wmt_setbits(data, reg_pull_cfg, BIT(bit));
 456                        wmt_setbits(data, reg_pull_en, BIT(bit));
 457                        break;
 458                default:
 459                        dev_err(data->dev, "unknown pinconf param\n");
 460                        return -EINVAL;
 461                }
 462        } /* for each config */
 463
 464        return 0;
 465}
 466
 467static const struct pinconf_ops wmt_pinconf_ops = {
 468        .pin_config_get = wmt_pinconf_get,
 469        .pin_config_set = wmt_pinconf_set,
 470};
 471
 472static struct pinctrl_desc wmt_desc = {
 473        .owner = THIS_MODULE,
 474        .name = "pinctrl-wmt",
 475        .pctlops = &wmt_pctl_ops,
 476        .pmxops = &wmt_pinmux_ops,
 477        .confops = &wmt_pinconf_ops,
 478};
 479
 480static int wmt_gpio_get_direction(struct gpio_chip *chip, unsigned offset)
 481{
 482        struct wmt_pinctrl_data *data = gpiochip_get_data(chip);
 483        u32 bank = WMT_BANK_FROM_PIN(offset);
 484        u32 bit = WMT_BIT_FROM_PIN(offset);
 485        u32 reg_dir = data->banks[bank].reg_dir;
 486        u32 val;
 487
 488        val = readl_relaxed(data->base + reg_dir);
 489        if (val & BIT(bit))
 490                return GPIO_LINE_DIRECTION_OUT;
 491
 492        return GPIO_LINE_DIRECTION_IN;
 493}
 494
 495static int wmt_gpio_get_value(struct gpio_chip *chip, unsigned offset)
 496{
 497        struct wmt_pinctrl_data *data = gpiochip_get_data(chip);
 498        u32 bank = WMT_BANK_FROM_PIN(offset);
 499        u32 bit = WMT_BIT_FROM_PIN(offset);
 500        u32 reg_data_in = data->banks[bank].reg_data_in;
 501
 502        if (reg_data_in == NO_REG) {
 503                dev_err(data->dev, "no data in register defined\n");
 504                return -EINVAL;
 505        }
 506
 507        return !!(readl_relaxed(data->base + reg_data_in) & BIT(bit));
 508}
 509
 510static void wmt_gpio_set_value(struct gpio_chip *chip, unsigned offset,
 511                               int val)
 512{
 513        struct wmt_pinctrl_data *data = gpiochip_get_data(chip);
 514        u32 bank = WMT_BANK_FROM_PIN(offset);
 515        u32 bit = WMT_BIT_FROM_PIN(offset);
 516        u32 reg_data_out = data->banks[bank].reg_data_out;
 517
 518        if (reg_data_out == NO_REG) {
 519                dev_err(data->dev, "no data out register defined\n");
 520                return;
 521        }
 522
 523        if (val)
 524                wmt_setbits(data, reg_data_out, BIT(bit));
 525        else
 526                wmt_clearbits(data, reg_data_out, BIT(bit));
 527}
 528
 529static int wmt_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 530{
 531        return pinctrl_gpio_direction_input(chip->base + offset);
 532}
 533
 534static int wmt_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
 535                                     int value)
 536{
 537        wmt_gpio_set_value(chip, offset, value);
 538        return pinctrl_gpio_direction_output(chip->base + offset);
 539}
 540
 541static const struct gpio_chip wmt_gpio_chip = {
 542        .label = "gpio-wmt",
 543        .owner = THIS_MODULE,
 544        .request = gpiochip_generic_request,
 545        .free = gpiochip_generic_free,
 546        .get_direction = wmt_gpio_get_direction,
 547        .direction_input = wmt_gpio_direction_input,
 548        .direction_output = wmt_gpio_direction_output,
 549        .get = wmt_gpio_get_value,
 550        .set = wmt_gpio_set_value,
 551        .can_sleep = false,
 552};
 553
 554int wmt_pinctrl_probe(struct platform_device *pdev,
 555                      struct wmt_pinctrl_data *data)
 556{
 557        int err;
 558
 559        data->base = devm_platform_ioremap_resource(pdev, 0);
 560        if (IS_ERR(data->base))
 561                return PTR_ERR(data->base);
 562
 563        wmt_desc.pins = data->pins;
 564        wmt_desc.npins = data->npins;
 565
 566        data->gpio_chip = wmt_gpio_chip;
 567        data->gpio_chip.parent = &pdev->dev;
 568        data->gpio_chip.of_node = pdev->dev.of_node;
 569        data->gpio_chip.ngpio = data->nbanks * 32;
 570
 571        platform_set_drvdata(pdev, data);
 572
 573        data->dev = &pdev->dev;
 574
 575        data->pctl_dev = devm_pinctrl_register(&pdev->dev, &wmt_desc, data);
 576        if (IS_ERR(data->pctl_dev)) {
 577                dev_err(&pdev->dev, "Failed to register pinctrl\n");
 578                return PTR_ERR(data->pctl_dev);
 579        }
 580
 581        err = gpiochip_add_data(&data->gpio_chip, data);
 582        if (err) {
 583                dev_err(&pdev->dev, "could not add GPIO chip\n");
 584                return err;
 585        }
 586
 587        err = gpiochip_add_pin_range(&data->gpio_chip, dev_name(data->dev),
 588                                     0, 0, data->nbanks * 32);
 589        if (err)
 590                goto fail_range;
 591
 592        dev_info(&pdev->dev, "Pin controller initialized\n");
 593
 594        return 0;
 595
 596fail_range:
 597        gpiochip_remove(&data->gpio_chip);
 598        return err;
 599}
 600