linux/drivers/pinctrl/vt8500/pinctrl-wmt.c
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   1/*
   2 * Pinctrl driver for the Wondermedia SoC's
   3 *
   4 * Copyright (c) 2013 Tony Prisk <linux@prisktech.co.nz>
   5 *
   6 * This program is free software; you can redistribute it and/or modify it
   7 * under the terms and conditions of the GNU General Public License,
   8 * version 2, as published by the Free Software Foundation.
   9 *
  10 * This program is distributed in the hope it will be useful, but WITHOUT
  11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13 * more details.
  14 */
  15
  16#include <linux/err.h>
  17#include <linux/gpio.h>
  18#include <linux/interrupt.h>
  19#include <linux/io.h>
  20#include <linux/irq.h>
  21#include <linux/module.h>
  22#include <linux/of.h>
  23#include <linux/of_irq.h>
  24#include <linux/pinctrl/consumer.h>
  25#include <linux/pinctrl/machine.h>
  26#include <linux/pinctrl/pinconf.h>
  27#include <linux/pinctrl/pinconf-generic.h>
  28#include <linux/pinctrl/pinctrl.h>
  29#include <linux/pinctrl/pinmux.h>
  30#include <linux/platform_device.h>
  31#include <linux/slab.h>
  32
  33#include "pinctrl-wmt.h"
  34
  35static inline void wmt_setbits(struct wmt_pinctrl_data *data, u32 reg,
  36                                 u32 mask)
  37{
  38        u32 val;
  39
  40        val = readl_relaxed(data->base + reg);
  41        val |= mask;
  42        writel_relaxed(val, data->base + reg);
  43}
  44
  45static inline void wmt_clearbits(struct wmt_pinctrl_data *data, u32 reg,
  46                                   u32 mask)
  47{
  48        u32 val;
  49
  50        val = readl_relaxed(data->base + reg);
  51        val &= ~mask;
  52        writel_relaxed(val, data->base + reg);
  53}
  54
  55enum wmt_func_sel {
  56        WMT_FSEL_GPIO_IN = 0,
  57        WMT_FSEL_GPIO_OUT = 1,
  58        WMT_FSEL_ALT = 2,
  59        WMT_FSEL_COUNT = 3,
  60};
  61
  62static const char * const wmt_functions[WMT_FSEL_COUNT] = {
  63        [WMT_FSEL_GPIO_IN] = "gpio_in",
  64        [WMT_FSEL_GPIO_OUT] = "gpio_out",
  65        [WMT_FSEL_ALT] = "alt",
  66};
  67
  68static int wmt_pmx_get_functions_count(struct pinctrl_dev *pctldev)
  69{
  70        return WMT_FSEL_COUNT;
  71}
  72
  73static const char *wmt_pmx_get_function_name(struct pinctrl_dev *pctldev,
  74                                             unsigned selector)
  75{
  76        return wmt_functions[selector];
  77}
  78
  79static int wmt_pmx_get_function_groups(struct pinctrl_dev *pctldev,
  80                                       unsigned selector,
  81                                       const char * const **groups,
  82                                       unsigned * const num_groups)
  83{
  84        struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
  85
  86        /* every pin does every function */
  87        *groups = data->groups;
  88        *num_groups = data->ngroups;
  89
  90        return 0;
  91}
  92
  93static int wmt_set_pinmux(struct wmt_pinctrl_data *data, unsigned func,
  94                          unsigned pin)
  95{
  96        u32 bank = WMT_BANK_FROM_PIN(pin);
  97        u32 bit = WMT_BIT_FROM_PIN(pin);
  98        u32 reg_en = data->banks[bank].reg_en;
  99        u32 reg_dir = data->banks[bank].reg_dir;
 100
 101        if (reg_dir == NO_REG) {
 102                dev_err(data->dev, "pin:%d no direction register defined\n",
 103                        pin);
 104                return -EINVAL;
 105        }
 106
 107        /*
 108         * If reg_en == NO_REG, we assume it is a dedicated GPIO and cannot be
 109         * disabled (as on VT8500) and that no alternate function is available.
 110         */
 111        switch (func) {
 112        case WMT_FSEL_GPIO_IN:
 113                if (reg_en != NO_REG)
 114                        wmt_setbits(data, reg_en, BIT(bit));
 115                wmt_clearbits(data, reg_dir, BIT(bit));
 116                break;
 117        case WMT_FSEL_GPIO_OUT:
 118                if (reg_en != NO_REG)
 119                        wmt_setbits(data, reg_en, BIT(bit));
 120                wmt_setbits(data, reg_dir, BIT(bit));
 121                break;
 122        case WMT_FSEL_ALT:
 123                if (reg_en == NO_REG) {
 124                        dev_err(data->dev, "pin:%d no alt function available\n",
 125                                pin);
 126                        return -EINVAL;
 127                }
 128                wmt_clearbits(data, reg_en, BIT(bit));
 129        }
 130
 131        return 0;
 132}
 133
 134static int wmt_pmx_enable(struct pinctrl_dev *pctldev,
 135                          unsigned func_selector,
 136                          unsigned group_selector)
 137{
 138        struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
 139        u32 pinnum = data->pins[group_selector].number;
 140
 141        return wmt_set_pinmux(data, func_selector, pinnum);
 142}
 143
 144static void wmt_pmx_disable(struct pinctrl_dev *pctldev,
 145                            unsigned func_selector,
 146                            unsigned group_selector)
 147{
 148        struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
 149        u32 pinnum = data->pins[group_selector].number;
 150
 151        /* disable by setting GPIO_IN */
 152        wmt_set_pinmux(data, WMT_FSEL_GPIO_IN, pinnum);
 153}
 154
 155static void wmt_pmx_gpio_disable_free(struct pinctrl_dev *pctldev,
 156                                      struct pinctrl_gpio_range *range,
 157                                      unsigned offset)
 158{
 159        struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
 160
 161        /* disable by setting GPIO_IN */
 162        wmt_set_pinmux(data, WMT_FSEL_GPIO_IN, offset);
 163}
 164
 165static int wmt_pmx_gpio_set_direction(struct pinctrl_dev *pctldev,
 166                                      struct pinctrl_gpio_range *range,
 167                                      unsigned offset,
 168                                      bool input)
 169{
 170        struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
 171
 172        wmt_set_pinmux(data, (input ? WMT_FSEL_GPIO_IN : WMT_FSEL_GPIO_OUT),
 173                       offset);
 174
 175        return 0;
 176}
 177
 178static struct pinmux_ops wmt_pinmux_ops = {
 179        .get_functions_count = wmt_pmx_get_functions_count,
 180        .get_function_name = wmt_pmx_get_function_name,
 181        .get_function_groups = wmt_pmx_get_function_groups,
 182        .enable = wmt_pmx_enable,
 183        .disable = wmt_pmx_disable,
 184        .gpio_disable_free = wmt_pmx_gpio_disable_free,
 185        .gpio_set_direction = wmt_pmx_gpio_set_direction,
 186};
 187
 188static int wmt_get_groups_count(struct pinctrl_dev *pctldev)
 189{
 190        struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
 191
 192        return data->ngroups;
 193}
 194
 195static const char *wmt_get_group_name(struct pinctrl_dev *pctldev,
 196                                      unsigned selector)
 197{
 198        struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
 199
 200        return data->groups[selector];
 201}
 202
 203static int wmt_get_group_pins(struct pinctrl_dev *pctldev,
 204                              unsigned selector,
 205                              const unsigned **pins,
 206                              unsigned *num_pins)
 207{
 208        struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
 209
 210        *pins = &data->pins[selector].number;
 211        *num_pins = 1;
 212
 213        return 0;
 214}
 215
 216static int wmt_pctl_find_group_by_pin(struct wmt_pinctrl_data *data, u32 pin)
 217{
 218        int i;
 219
 220        for (i = 0; i < data->npins; i++) {
 221                if (data->pins[i].number == pin)
 222                        return i;
 223        }
 224
 225        return -EINVAL;
 226}
 227
 228static int wmt_pctl_dt_node_to_map_func(struct wmt_pinctrl_data *data,
 229                                        struct device_node *np,
 230                                        u32 pin, u32 fnum,
 231                                        struct pinctrl_map **maps)
 232{
 233        int group;
 234        struct pinctrl_map *map = *maps;
 235
 236        if (fnum >= ARRAY_SIZE(wmt_functions)) {
 237                dev_err(data->dev, "invalid wm,function %d\n", fnum);
 238                return -EINVAL;
 239        }
 240
 241        group = wmt_pctl_find_group_by_pin(data, pin);
 242        if (group < 0) {
 243                dev_err(data->dev, "unable to match pin %d to group\n", pin);
 244                return group;
 245        }
 246
 247        map->type = PIN_MAP_TYPE_MUX_GROUP;
 248        map->data.mux.group = data->groups[group];
 249        map->data.mux.function = wmt_functions[fnum];
 250        (*maps)++;
 251
 252        return 0;
 253}
 254
 255static int wmt_pctl_dt_node_to_map_pull(struct wmt_pinctrl_data *data,
 256                                        struct device_node *np,
 257                                        u32 pin, u32 pull,
 258                                        struct pinctrl_map **maps)
 259{
 260        int group;
 261        unsigned long *configs;
 262        struct pinctrl_map *map = *maps;
 263
 264        if (pull > 2) {
 265                dev_err(data->dev, "invalid wm,pull %d\n", pull);
 266                return -EINVAL;
 267        }
 268
 269        group = wmt_pctl_find_group_by_pin(data, pin);
 270        if (group < 0) {
 271                dev_err(data->dev, "unable to match pin %d to group\n", pin);
 272                return group;
 273        }
 274
 275        configs = kzalloc(sizeof(*configs), GFP_KERNEL);
 276        if (!configs)
 277                return -ENOMEM;
 278
 279        configs[0] = pull;
 280
 281        map->type = PIN_MAP_TYPE_CONFIGS_PIN;
 282        map->data.configs.group_or_pin = data->groups[group];
 283        map->data.configs.configs = configs;
 284        map->data.configs.num_configs = 1;
 285        (*maps)++;
 286
 287        return 0;
 288}
 289
 290static void wmt_pctl_dt_free_map(struct pinctrl_dev *pctldev,
 291                                 struct pinctrl_map *maps,
 292                                 unsigned num_maps)
 293{
 294        int i;
 295
 296        for (i = 0; i < num_maps; i++)
 297                if (maps[i].type == PIN_MAP_TYPE_CONFIGS_PIN)
 298                        kfree(maps[i].data.configs.configs);
 299
 300        kfree(maps);
 301}
 302
 303static int wmt_pctl_dt_node_to_map(struct pinctrl_dev *pctldev,
 304                                   struct device_node *np,
 305                                   struct pinctrl_map **map,
 306                                   unsigned *num_maps)
 307{
 308        struct pinctrl_map *maps, *cur_map;
 309        struct property *pins, *funcs, *pulls;
 310        u32 pin, func, pull;
 311        int num_pins, num_funcs, num_pulls, maps_per_pin;
 312        int i, err;
 313        struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
 314
 315        pins = of_find_property(np, "wm,pins", NULL);
 316        if (!pins) {
 317                dev_err(data->dev, "missing wmt,pins property\n");
 318                return -EINVAL;
 319        }
 320
 321        funcs = of_find_property(np, "wm,function", NULL);
 322        pulls = of_find_property(np, "wm,pull", NULL);
 323
 324        if (!funcs && !pulls) {
 325                dev_err(data->dev, "neither wm,function nor wm,pull specified\n");
 326                return -EINVAL;
 327        }
 328
 329        /*
 330         * The following lines calculate how many values are defined for each
 331         * of the properties.
 332         */
 333        num_pins = pins->length / sizeof(u32);
 334        num_funcs = funcs ? (funcs->length / sizeof(u32)) : 0;
 335        num_pulls = pulls ? (pulls->length / sizeof(u32)) : 0;
 336
 337        if (num_funcs > 1 && num_funcs != num_pins) {
 338                dev_err(data->dev, "wm,function must have 1 or %d entries\n",
 339                        num_pins);
 340                return -EINVAL;
 341        }
 342
 343        if (num_pulls > 1 && num_pulls != num_pins) {
 344                dev_err(data->dev, "wm,pull must have 1 or %d entries\n",
 345                        num_pins);
 346                return -EINVAL;
 347        }
 348
 349        maps_per_pin = 0;
 350        if (num_funcs)
 351                maps_per_pin++;
 352        if (num_pulls)
 353                maps_per_pin++;
 354
 355        cur_map = maps = kzalloc(num_pins * maps_per_pin * sizeof(*maps),
 356                                 GFP_KERNEL);
 357        if (!maps)
 358                return -ENOMEM;
 359
 360        for (i = 0; i < num_pins; i++) {
 361                err = of_property_read_u32_index(np, "wm,pins", i, &pin);
 362                if (err)
 363                        goto fail;
 364
 365                if (pin >= (data->nbanks * 32)) {
 366                        dev_err(data->dev, "invalid wm,pins value\n");
 367                        err = -EINVAL;
 368                        goto fail;
 369                }
 370
 371                if (num_funcs) {
 372                        err = of_property_read_u32_index(np, "wm,function",
 373                                                (num_funcs > 1 ? i : 0), &func);
 374                        if (err)
 375                                goto fail;
 376
 377                        err = wmt_pctl_dt_node_to_map_func(data, np, pin, func,
 378                                                           &cur_map);
 379                        if (err)
 380                                goto fail;
 381                }
 382
 383                if (num_pulls) {
 384                        err = of_property_read_u32_index(np, "wm,pull",
 385                                                (num_pulls > 1 ? i : 0), &pull);
 386                        if (err)
 387                                goto fail;
 388
 389                        err = wmt_pctl_dt_node_to_map_pull(data, np, pin, pull,
 390                                                           &cur_map);
 391                        if (err)
 392                                goto fail;
 393                }
 394        }
 395        *map = maps;
 396        *num_maps = num_pins * maps_per_pin;
 397        return 0;
 398
 399/*
 400 * The fail path removes any maps that have been allocated. The fail path is
 401 * only called from code after maps has been kzalloc'd. It is also safe to
 402 * pass 'num_pins * maps_per_pin' as the map count even though we probably
 403 * failed before all the mappings were read as all maps are allocated at once,
 404 * and configs are only allocated for .type = PIN_MAP_TYPE_CONFIGS_PIN - there
 405 * is no failpath where a config can be allocated without .type being set.
 406 */
 407fail:
 408        wmt_pctl_dt_free_map(pctldev, maps, num_pins * maps_per_pin);
 409        return err;
 410}
 411
 412static struct pinctrl_ops wmt_pctl_ops = {
 413        .get_groups_count = wmt_get_groups_count,
 414        .get_group_name = wmt_get_group_name,
 415        .get_group_pins = wmt_get_group_pins,
 416        .dt_node_to_map = wmt_pctl_dt_node_to_map,
 417        .dt_free_map = wmt_pctl_dt_free_map,
 418};
 419
 420static int wmt_pinconf_get(struct pinctrl_dev *pctldev, unsigned pin,
 421                           unsigned long *config)
 422{
 423        return -ENOTSUPP;
 424}
 425
 426static int wmt_pinconf_set(struct pinctrl_dev *pctldev, unsigned pin,
 427                           unsigned long config)
 428{
 429        struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
 430        enum pin_config_param param = pinconf_to_config_param(config);
 431        u16 arg = pinconf_to_config_argument(config);
 432        u32 bank = WMT_BANK_FROM_PIN(pin);
 433        u32 bit = WMT_BIT_FROM_PIN(pin);
 434        u32 reg_pull_en = data->banks[bank].reg_pull_en;
 435        u32 reg_pull_cfg = data->banks[bank].reg_pull_cfg;
 436
 437        if ((reg_pull_en == NO_REG) || (reg_pull_cfg == NO_REG)) {
 438                dev_err(data->dev, "bias functions not supported on pin %d\n",
 439                        pin);
 440                return -EINVAL;
 441        }
 442
 443        if ((param == PIN_CONFIG_BIAS_PULL_DOWN) ||
 444            (param == PIN_CONFIG_BIAS_PULL_UP)) {
 445                if (arg == 0)
 446                        param = PIN_CONFIG_BIAS_DISABLE;
 447        }
 448
 449        switch (param) {
 450        case PIN_CONFIG_BIAS_DISABLE:
 451                wmt_clearbits(data, reg_pull_en, BIT(bit));
 452                break;
 453        case PIN_CONFIG_BIAS_PULL_DOWN:
 454                wmt_clearbits(data, reg_pull_cfg, BIT(bit));
 455                wmt_setbits(data, reg_pull_en, BIT(bit));
 456                break;
 457        case PIN_CONFIG_BIAS_PULL_UP:
 458                wmt_setbits(data, reg_pull_cfg, BIT(bit));
 459                wmt_setbits(data, reg_pull_en, BIT(bit));
 460                break;
 461        default:
 462                dev_err(data->dev, "unknown pinconf param\n");
 463                return -EINVAL;
 464        }
 465
 466        return 0;
 467}
 468
 469static struct pinconf_ops wmt_pinconf_ops = {
 470        .pin_config_get = wmt_pinconf_get,
 471        .pin_config_set = wmt_pinconf_set,
 472};
 473
 474static struct pinctrl_desc wmt_desc = {
 475        .owner = THIS_MODULE,
 476        .name = "pinctrl-wmt",
 477        .pctlops = &wmt_pctl_ops,
 478        .pmxops = &wmt_pinmux_ops,
 479        .confops = &wmt_pinconf_ops,
 480};
 481
 482static int wmt_gpio_request(struct gpio_chip *chip, unsigned offset)
 483{
 484        return pinctrl_request_gpio(chip->base + offset);
 485}
 486
 487static void wmt_gpio_free(struct gpio_chip *chip, unsigned offset)
 488{
 489        pinctrl_free_gpio(chip->base + offset);
 490}
 491
 492static int wmt_gpio_get_direction(struct gpio_chip *chip, unsigned offset)
 493{
 494        struct wmt_pinctrl_data *data = dev_get_drvdata(chip->dev);
 495        u32 bank = WMT_BANK_FROM_PIN(offset);
 496        u32 bit = WMT_BIT_FROM_PIN(offset);
 497        u32 reg_dir = data->banks[bank].reg_dir;
 498        u32 val;
 499
 500        val = readl_relaxed(data->base + reg_dir);
 501        if (val & BIT(bit))
 502                return GPIOF_DIR_OUT;
 503        else
 504                return GPIOF_DIR_IN;
 505}
 506
 507static int wmt_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 508{
 509        return pinctrl_gpio_direction_input(chip->base + offset);
 510}
 511
 512static int wmt_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
 513                                     int value)
 514{
 515        return pinctrl_gpio_direction_output(chip->base + offset);
 516}
 517
 518static int wmt_gpio_get_value(struct gpio_chip *chip, unsigned offset)
 519{
 520        struct wmt_pinctrl_data *data = dev_get_drvdata(chip->dev);
 521        u32 bank = WMT_BANK_FROM_PIN(offset);
 522        u32 bit = WMT_BIT_FROM_PIN(offset);
 523        u32 reg_data_in = data->banks[bank].reg_data_in;
 524
 525        if (reg_data_in == NO_REG) {
 526                dev_err(data->dev, "no data in register defined\n");
 527                return -EINVAL;
 528        }
 529
 530        return !!(readl_relaxed(data->base + reg_data_in) & BIT(bit));
 531}
 532
 533static void wmt_gpio_set_value(struct gpio_chip *chip, unsigned offset,
 534                               int val)
 535{
 536        struct wmt_pinctrl_data *data = dev_get_drvdata(chip->dev);
 537        u32 bank = WMT_BANK_FROM_PIN(offset);
 538        u32 bit = WMT_BIT_FROM_PIN(offset);
 539        u32 reg_data_out = data->banks[bank].reg_data_out;
 540
 541        if (reg_data_out == NO_REG) {
 542                dev_err(data->dev, "no data out register defined\n");
 543                return;
 544        }
 545
 546        if (val)
 547                wmt_setbits(data, reg_data_out, BIT(bit));
 548        else
 549                wmt_clearbits(data, reg_data_out, BIT(bit));
 550}
 551
 552static struct gpio_chip wmt_gpio_chip = {
 553        .label = "gpio-wmt",
 554        .owner = THIS_MODULE,
 555        .request = wmt_gpio_request,
 556        .free = wmt_gpio_free,
 557        .get_direction = wmt_gpio_get_direction,
 558        .direction_input = wmt_gpio_direction_input,
 559        .direction_output = wmt_gpio_direction_output,
 560        .get = wmt_gpio_get_value,
 561        .set = wmt_gpio_set_value,
 562        .can_sleep = 0,
 563};
 564
 565int wmt_pinctrl_probe(struct platform_device *pdev,
 566                      struct wmt_pinctrl_data *data)
 567{
 568        int err;
 569        struct resource *res;
 570
 571        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 572        data->base = devm_request_and_ioremap(&pdev->dev, res);
 573        if (!data->base) {
 574                dev_err(&pdev->dev, "failed to map memory resource\n");
 575                return -EBUSY;
 576        }
 577
 578        wmt_desc.pins = data->pins;
 579        wmt_desc.npins = data->npins;
 580
 581        data->gpio_chip = wmt_gpio_chip;
 582        data->gpio_chip.dev = &pdev->dev;
 583        data->gpio_chip.of_node = pdev->dev.of_node;
 584        data->gpio_chip.ngpio = data->nbanks * 32;
 585
 586        platform_set_drvdata(pdev, data);
 587
 588        data->dev = &pdev->dev;
 589
 590        data->pctl_dev = pinctrl_register(&wmt_desc, &pdev->dev, data);
 591        if (!data->pctl_dev) {
 592                dev_err(&pdev->dev, "Failed to register pinctrl\n");
 593                return -EINVAL;
 594        }
 595
 596        err = gpiochip_add(&data->gpio_chip);
 597        if (err) {
 598                dev_err(&pdev->dev, "could not add GPIO chip\n");
 599                goto fail_gpio;
 600        }
 601
 602        err = gpiochip_add_pin_range(&data->gpio_chip, dev_name(data->dev),
 603                                     0, 0, data->nbanks * 32);
 604        if (err)
 605                goto fail_range;
 606
 607        dev_info(&pdev->dev, "Pin controller initialized\n");
 608
 609        return 0;
 610
 611fail_range:
 612        if (gpiochip_remove(&data->gpio_chip))
 613                dev_err(&pdev->dev, "failed to remove gpio chip\n");
 614fail_gpio:
 615        pinctrl_unregister(data->pctl_dev);
 616        return err;
 617}
 618
 619int wmt_pinctrl_remove(struct platform_device *pdev)
 620{
 621        struct wmt_pinctrl_data *data = platform_get_drvdata(pdev);
 622        int err;
 623
 624        err = gpiochip_remove(&data->gpio_chip);
 625        if (err)
 626                dev_err(&pdev->dev, "failed to remove gpio chip\n");
 627
 628        pinctrl_unregister(data->pctl_dev);
 629
 630        return 0;
 631}
 632