drivers/pinctrl/vt8500/pinctrl-wmt.c

   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
  26 static 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
  36 static 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
  46 enum 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
  53 static 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
  59 static int wmt_pmx_get_functions_count(struct pinctrl_dev *pctldev)
  60 {
  61         return WMT_FSEL_COUNT;
  62 }
  63
  64 static const char *wmt_pmx_get_function_name(struct pinctrl_dev *pctldev,
  65                                              unsigned selector)
  66 {
  67         return wmt_functions[selector];
  68 }
  69
  70 static 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
  84 static 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
 125 static 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
 135 static 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
 145 static 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
 158 static 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
 167 static 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
 174 static 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
 182 static 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
 195 static 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
 207 static 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
 234 static 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
 282 static 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
 295 static 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  */
 399 fail:
 400         wmt_pctl_dt_free_map(pctldev, maps, num_pins * maps_per_pin);
 401         return err;
 402 }
 403
 404 static 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
 412 static int wmt_pinconf_get(struct pinctrl_dev *pctldev, unsigned pin,
 413                            unsigned long *config)
 414 {
 415         return -ENOTSUPP;
 416 }
 417
 418 static 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
 467 static const struct pinconf_ops wmt_pinconf_ops = {
 468         .pin_config_get = wmt_pinconf_get,
 469         .pin_config_set = wmt_pinconf_set,
 470 };
 471
 472 static 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
 480 static 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         /* Return 0 == output, 1 == input */
 490         return !(val & BIT(bit));
 491 }
 492
 493 static int wmt_gpio_get_value(struct gpio_chip *chip, unsigned offset)
 494 {
 495         struct wmt_pinctrl_data *data = gpiochip_get_data(chip);
 496         u32 bank = WMT_BANK_FROM_PIN(offset);
 497         u32 bit = WMT_BIT_FROM_PIN(offset);
 498         u32 reg_data_in = data->banks[bank].reg_data_in;
 499
 500         if (reg_data_in == NO_REG) {
 501                 dev_err(data->dev, "no data in register defined\n");
 502                 return -EINVAL;
 503         }
 504
 505         return !!(readl_relaxed(data->base + reg_data_in) & BIT(bit));
 506 }
 507
 508 static void wmt_gpio_set_value(struct gpio_chip *chip, unsigned offset,
 509                                int val)
 510 {
 511         struct wmt_pinctrl_data *data = gpiochip_get_data(chip);
 512         u32 bank = WMT_BANK_FROM_PIN(offset);
 513         u32 bit = WMT_BIT_FROM_PIN(offset);
 514         u32 reg_data_out = data->banks[bank].reg_data_out;
 515
 516         if (reg_data_out == NO_REG) {
 517                 dev_err(data->dev, "no data out register defined\n");
 518                 return;
 519         }
 520
 521         if (val)
 522                 wmt_setbits(data, reg_data_out, BIT(bit));
 523         else
 524                 wmt_clearbits(data, reg_data_out, BIT(bit));
 525 }
 526
 527 static int wmt_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 528 {
 529         return pinctrl_gpio_direction_input(chip->base + offset);
 530 }
 531
 532 static int wmt_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
 533                                      int value)
 534 {
 535         wmt_gpio_set_value(chip, offset, value);
 536         return pinctrl_gpio_direction_output(chip->base + offset);
 537 }
 538
 539 static const struct gpio_chip wmt_gpio_chip = {
 540         .label = "gpio-wmt",
 541         .owner = THIS_MODULE,
 542         .request = gpiochip_generic_request,
 543         .free = gpiochip_generic_free,
 544         .get_direction = wmt_gpio_get_direction,
 545         .direction_input = wmt_gpio_direction_input,
 546         .direction_output = wmt_gpio_direction_output,
 547         .get = wmt_gpio_get_value,
 548         .set = wmt_gpio_set_value,
 549         .can_sleep = false,
 550 };
 551
 552 int wmt_pinctrl_probe(struct platform_device *pdev,
 553                       struct wmt_pinctrl_data *data)
 554 {
 555         int err;
 556         struct resource *res;
 557
 558         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 559         data->base = devm_ioremap_resource(&pdev->dev, res);
 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
 596 fail_range:
 597         gpiochip_remove(&data->gpio_chip);
 598         return err;
 599 }