drivers/pinctrl/vt8500/pinctrl-wmt.c

   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
  35 static 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
  45 static 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
  55 enum 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
  62 static 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
  68 static int wmt_pmx_get_functions_count(struct pinctrl_dev *pctldev)
  69 {
  70         return WMT_FSEL_COUNT;
  71 }
  72
  73 static const char *wmt_pmx_get_function_name(struct pinctrl_dev *pctldev,
  74                                              unsigned selector)
  75 {
  76         return wmt_functions[selector];
  77 }
  78
  79 static 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
  93 static 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
 134 static int wmt_pmx_set_mux(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
 144 static void wmt_pmx_gpio_disable_free(struct pinctrl_dev *pctldev,
 145                                       struct pinctrl_gpio_range *range,
 146                                       unsigned offset)
 147 {
 148         struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
 149
 150         /* disable by setting GPIO_IN */
 151         wmt_set_pinmux(data, WMT_FSEL_GPIO_IN, offset);
 152 }
 153
 154 static int wmt_pmx_gpio_set_direction(struct pinctrl_dev *pctldev,
 155                                       struct pinctrl_gpio_range *range,
 156                                       unsigned offset,
 157                                       bool input)
 158 {
 159         struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
 160
 161         wmt_set_pinmux(data, (input ? WMT_FSEL_GPIO_IN : WMT_FSEL_GPIO_OUT),
 162                        offset);
 163
 164         return 0;
 165 }
 166
 167 static struct pinmux_ops wmt_pinmux_ops = {
 168         .get_functions_count = wmt_pmx_get_functions_count,
 169         .get_function_name = wmt_pmx_get_function_name,
 170         .get_function_groups = wmt_pmx_get_function_groups,
 171         .set_mux = wmt_pmx_set_mux,
 172         .gpio_disable_free = wmt_pmx_gpio_disable_free,
 173         .gpio_set_direction = wmt_pmx_gpio_set_direction,
 174 };
 175
 176 static int wmt_get_groups_count(struct pinctrl_dev *pctldev)
 177 {
 178         struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
 179
 180         return data->ngroups;
 181 }
 182
 183 static const char *wmt_get_group_name(struct pinctrl_dev *pctldev,
 184                                       unsigned selector)
 185 {
 186         struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
 187
 188         return data->groups[selector];
 189 }
 190
 191 static int wmt_get_group_pins(struct pinctrl_dev *pctldev,
 192                               unsigned selector,
 193                               const unsigned **pins,
 194                               unsigned *num_pins)
 195 {
 196         struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
 197
 198         *pins = &data->pins[selector].number;
 199         *num_pins = 1;
 200
 201         return 0;
 202 }
 203
 204 static int wmt_pctl_find_group_by_pin(struct wmt_pinctrl_data *data, u32 pin)
 205 {
 206         int i;
 207
 208         for (i = 0; i < data->npins; i++) {
 209                 if (data->pins[i].number == pin)
 210                         return i;
 211         }
 212
 213         return -EINVAL;
 214 }
 215
 216 static int wmt_pctl_dt_node_to_map_func(struct wmt_pinctrl_data *data,
 217                                         struct device_node *np,
 218                                         u32 pin, u32 fnum,
 219                                         struct pinctrl_map **maps)
 220 {
 221         int group;
 222         struct pinctrl_map *map = *maps;
 223
 224         if (fnum >= ARRAY_SIZE(wmt_functions)) {
 225                 dev_err(data->dev, "invalid wm,function %d\n", fnum);
 226                 return -EINVAL;
 227         }
 228
 229         group = wmt_pctl_find_group_by_pin(data, pin);
 230         if (group < 0) {
 231                 dev_err(data->dev, "unable to match pin %d to group\n", pin);
 232                 return group;
 233         }
 234
 235         map->type = PIN_MAP_TYPE_MUX_GROUP;
 236         map->data.mux.group = data->groups[group];
 237         map->data.mux.function = wmt_functions[fnum];
 238         (*maps)++;
 239
 240         return 0;
 241 }
 242
 243 static int wmt_pctl_dt_node_to_map_pull(struct wmt_pinctrl_data *data,
 244                                         struct device_node *np,
 245                                         u32 pin, u32 pull,
 246                                         struct pinctrl_map **maps)
 247 {
 248         int group;
 249         unsigned long *configs;
 250         struct pinctrl_map *map = *maps;
 251
 252         if (pull > 2) {
 253                 dev_err(data->dev, "invalid wm,pull %d\n", pull);
 254                 return -EINVAL;
 255         }
 256
 257         group = wmt_pctl_find_group_by_pin(data, pin);
 258         if (group < 0) {
 259                 dev_err(data->dev, "unable to match pin %d to group\n", pin);
 260                 return group;
 261         }
 262
 263         configs = kzalloc(sizeof(*configs), GFP_KERNEL);
 264         if (!configs)
 265                 return -ENOMEM;
 266
 267         switch (pull) {
 268         case 0:
 269                 configs[0] = PIN_CONFIG_BIAS_DISABLE;
 270                 break;
 271         case 1:
 272                 configs[0] = PIN_CONFIG_BIAS_PULL_DOWN;
 273                 break;
 274         case 2:
 275                 configs[0] = PIN_CONFIG_BIAS_PULL_UP;
 276                 break;
 277         default:
 278                 configs[0] = PIN_CONFIG_BIAS_DISABLE;
 279                 dev_err(data->dev, "invalid pull state %d - disabling\n", pull);
 280         }
 281
 282         map->type = PIN_MAP_TYPE_CONFIGS_PIN;
 283         map->data.configs.group_or_pin = data->groups[group];
 284         map->data.configs.configs = configs;
 285         map->data.configs.num_configs = 1;
 286         (*maps)++;
 287
 288         return 0;
 289 }
 290
 291 static void wmt_pctl_dt_free_map(struct pinctrl_dev *pctldev,
 292                                  struct pinctrl_map *maps,
 293                                  unsigned num_maps)
 294 {
 295         int i;
 296
 297         for (i = 0; i < num_maps; i++)
 298                 if (maps[i].type == PIN_MAP_TYPE_CONFIGS_PIN)
 299                         kfree(maps[i].data.configs.configs);
 300
 301         kfree(maps);
 302 }
 303
 304 static int wmt_pctl_dt_node_to_map(struct pinctrl_dev *pctldev,
 305                                    struct device_node *np,
 306                                    struct pinctrl_map **map,
 307                                    unsigned *num_maps)
 308 {
 309         struct pinctrl_map *maps, *cur_map;
 310         struct property *pins, *funcs, *pulls;
 311         u32 pin, func, pull;
 312         int num_pins, num_funcs, num_pulls, maps_per_pin;
 313         int i, err;
 314         struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
 315
 316         pins = of_find_property(np, "wm,pins", NULL);
 317         if (!pins) {
 318                 dev_err(data->dev, "missing wmt,pins property\n");
 319                 return -EINVAL;
 320         }
 321
 322         funcs = of_find_property(np, "wm,function", NULL);
 323         pulls = of_find_property(np, "wm,pull", NULL);
 324
 325         if (!funcs && !pulls) {
 326                 dev_err(data->dev, "neither wm,function nor wm,pull specified\n");
 327                 return -EINVAL;
 328         }
 329
 330         /*
 331          * The following lines calculate how many values are defined for each
 332          * of the properties.
 333          */
 334         num_pins = pins->length / sizeof(u32);
 335         num_funcs = funcs ? (funcs->length / sizeof(u32)) : 0;
 336         num_pulls = pulls ? (pulls->length / sizeof(u32)) : 0;
 337
 338         if (num_funcs > 1 && num_funcs != num_pins) {
 339                 dev_err(data->dev, "wm,function must have 1 or %d entries\n",
 340                         num_pins);
 341                 return -EINVAL;
 342         }
 343
 344         if (num_pulls > 1 && num_pulls != num_pins) {
 345                 dev_err(data->dev, "wm,pull must have 1 or %d entries\n",
 346                         num_pins);
 347                 return -EINVAL;
 348         }
 349
 350         maps_per_pin = 0;
 351         if (num_funcs)
 352                 maps_per_pin++;
 353         if (num_pulls)
 354                 maps_per_pin++;
 355
 356         cur_map = maps = kzalloc(num_pins * maps_per_pin * sizeof(*maps),
 357                                  GFP_KERNEL);
 358         if (!maps)
 359                 return -ENOMEM;
 360
 361         for (i = 0; i < num_pins; i++) {
 362                 err = of_property_read_u32_index(np, "wm,pins", i, &pin);
 363                 if (err)
 364                         goto fail;
 365
 366                 if (pin >= (data->nbanks * 32)) {
 367                         dev_err(data->dev, "invalid wm,pins value\n");
 368                         err = -EINVAL;
 369                         goto fail;
 370                 }
 371
 372                 if (num_funcs) {
 373                         err = of_property_read_u32_index(np, "wm,function",
 374                                                 (num_funcs > 1 ? i : 0), &func);
 375                         if (err)
 376                                 goto fail;
 377
 378                         err = wmt_pctl_dt_node_to_map_func(data, np, pin, func,
 379                                                            &cur_map);
 380                         if (err)
 381                                 goto fail;
 382                 }
 383
 384                 if (num_pulls) {
 385                         err = of_property_read_u32_index(np, "wm,pull",
 386                                                 (num_pulls > 1 ? i : 0), &pull);
 387                         if (err)
 388                                 goto fail;
 389
 390                         err = wmt_pctl_dt_node_to_map_pull(data, np, pin, pull,
 391                                                            &cur_map);
 392                         if (err)
 393                                 goto fail;
 394                 }
 395         }
 396         *map = maps;
 397         *num_maps = num_pins * maps_per_pin;
 398         return 0;
 399
 400 /*
 401  * The fail path removes any maps that have been allocated. The fail path is
 402  * only called from code after maps has been kzalloc'd. It is also safe to
 403  * pass 'num_pins * maps_per_pin' as the map count even though we probably
 404  * failed before all the mappings were read as all maps are allocated at once,
 405  * and configs are only allocated for .type = PIN_MAP_TYPE_CONFIGS_PIN - there
 406  * is no failpath where a config can be allocated without .type being set.
 407  */
 408 fail:
 409         wmt_pctl_dt_free_map(pctldev, maps, num_pins * maps_per_pin);
 410         return err;
 411 }
 412
 413 static struct pinctrl_ops wmt_pctl_ops = {
 414         .get_groups_count = wmt_get_groups_count,
 415         .get_group_name = wmt_get_group_name,
 416         .get_group_pins = wmt_get_group_pins,
 417         .dt_node_to_map = wmt_pctl_dt_node_to_map,
 418         .dt_free_map = wmt_pctl_dt_free_map,
 419 };
 420
 421 static int wmt_pinconf_get(struct pinctrl_dev *pctldev, unsigned pin,
 422                            unsigned long *config)
 423 {
 424         return -ENOTSUPP;
 425 }
 426
 427 static int wmt_pinconf_set(struct pinctrl_dev *pctldev, unsigned pin,
 428                            unsigned long *configs, unsigned num_configs)
 429 {
 430         struct wmt_pinctrl_data *data = pinctrl_dev_get_drvdata(pctldev);
 431         enum pin_config_param param;
 432         u16 arg;
 433         u32 bank = WMT_BANK_FROM_PIN(pin);
 434         u32 bit = WMT_BIT_FROM_PIN(pin);
 435         u32 reg_pull_en = data->banks[bank].reg_pull_en;
 436         u32 reg_pull_cfg = data->banks[bank].reg_pull_cfg;
 437         int i;
 438
 439         if ((reg_pull_en == NO_REG) || (reg_pull_cfg == NO_REG)) {
 440                 dev_err(data->dev, "bias functions not supported on pin %d\n",
 441                         pin);
 442                 return -EINVAL;
 443         }
 444
 445         for (i = 0; i < num_configs; i++) {
 446                 param = pinconf_to_config_param(configs[i]);
 447                 arg = pinconf_to_config_argument(configs[i]);
 448
 449                 if ((param == PIN_CONFIG_BIAS_PULL_DOWN) ||
 450                     (param == PIN_CONFIG_BIAS_PULL_UP)) {
 451                         if (arg == 0)
 452                                 param = PIN_CONFIG_BIAS_DISABLE;
 453                 }
 454
 455                 switch (param) {
 456                 case PIN_CONFIG_BIAS_DISABLE:
 457                         wmt_clearbits(data, reg_pull_en, BIT(bit));
 458                         break;
 459                 case PIN_CONFIG_BIAS_PULL_DOWN:
 460                         wmt_clearbits(data, reg_pull_cfg, BIT(bit));
 461                         wmt_setbits(data, reg_pull_en, BIT(bit));
 462                         break;
 463                 case PIN_CONFIG_BIAS_PULL_UP:
 464                         wmt_setbits(data, reg_pull_cfg, BIT(bit));
 465                         wmt_setbits(data, reg_pull_en, BIT(bit));
 466                         break;
 467                 default:
 468                         dev_err(data->dev, "unknown pinconf param\n");
 469                         return -EINVAL;
 470                 }
 471         } /* for each config */
 472
 473         return 0;
 474 }
 475
 476 static struct pinconf_ops wmt_pinconf_ops = {
 477         .pin_config_get = wmt_pinconf_get,
 478         .pin_config_set = wmt_pinconf_set,
 479 };
 480
 481 static struct pinctrl_desc wmt_desc = {
 482         .owner = THIS_MODULE,
 483         .name = "pinctrl-wmt",
 484         .pctlops = &wmt_pctl_ops,
 485         .pmxops = &wmt_pinmux_ops,
 486         .confops = &wmt_pinconf_ops,
 487 };
 488
 489 static int wmt_gpio_request(struct gpio_chip *chip, unsigned offset)
 490 {
 491         return pinctrl_request_gpio(chip->base + offset);
 492 }
 493
 494 static void wmt_gpio_free(struct gpio_chip *chip, unsigned offset)
 495 {
 496         pinctrl_free_gpio(chip->base + offset);
 497 }
 498
 499 static int wmt_gpio_get_direction(struct gpio_chip *chip, unsigned offset)
 500 {
 501         struct wmt_pinctrl_data *data = dev_get_drvdata(chip->dev);
 502         u32 bank = WMT_BANK_FROM_PIN(offset);
 503         u32 bit = WMT_BIT_FROM_PIN(offset);
 504         u32 reg_dir = data->banks[bank].reg_dir;
 505         u32 val;
 506
 507         val = readl_relaxed(data->base + reg_dir);
 508         if (val & BIT(bit))
 509                 return GPIOF_DIR_OUT;
 510         else
 511                 return GPIOF_DIR_IN;
 512 }
 513
 514 static int wmt_gpio_get_value(struct gpio_chip *chip, unsigned offset)
 515 {
 516         struct wmt_pinctrl_data *data = dev_get_drvdata(chip->dev);
 517         u32 bank = WMT_BANK_FROM_PIN(offset);
 518         u32 bit = WMT_BIT_FROM_PIN(offset);
 519         u32 reg_data_in = data->banks[bank].reg_data_in;
 520
 521         if (reg_data_in == NO_REG) {
 522                 dev_err(data->dev, "no data in register defined\n");
 523                 return -EINVAL;
 524         }
 525
 526         return !!(readl_relaxed(data->base + reg_data_in) & BIT(bit));
 527 }
 528
 529 static void wmt_gpio_set_value(struct gpio_chip *chip, unsigned offset,
 530                                int val)
 531 {
 532         struct wmt_pinctrl_data *data = dev_get_drvdata(chip->dev);
 533         u32 bank = WMT_BANK_FROM_PIN(offset);
 534         u32 bit = WMT_BIT_FROM_PIN(offset);
 535         u32 reg_data_out = data->banks[bank].reg_data_out;
 536
 537         if (reg_data_out == NO_REG) {
 538                 dev_err(data->dev, "no data out register defined\n");
 539                 return;
 540         }
 541
 542         if (val)
 543                 wmt_setbits(data, reg_data_out, BIT(bit));
 544         else
 545                 wmt_clearbits(data, reg_data_out, BIT(bit));
 546 }
 547
 548 static int wmt_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 549 {
 550         return pinctrl_gpio_direction_input(chip->base + offset);
 551 }
 552
 553 static int wmt_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
 554                                      int value)
 555 {
 556         wmt_gpio_set_value(chip, offset, value);
 557         return pinctrl_gpio_direction_output(chip->base + offset);
 558 }
 559
 560 static struct gpio_chip wmt_gpio_chip = {
 561         .label = "gpio-wmt",
 562         .owner = THIS_MODULE,
 563         .request = wmt_gpio_request,
 564         .free = wmt_gpio_free,
 565         .get_direction = wmt_gpio_get_direction,
 566         .direction_input = wmt_gpio_direction_input,
 567         .direction_output = wmt_gpio_direction_output,
 568         .get = wmt_gpio_get_value,
 569         .set = wmt_gpio_set_value,
 570         .can_sleep = false,
 571 };
 572
 573 int wmt_pinctrl_probe(struct platform_device *pdev,
 574                       struct wmt_pinctrl_data *data)
 575 {
 576         int err;
 577         struct resource *res;
 578
 579         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 580         data->base = devm_ioremap_resource(&pdev->dev, res);
 581         if (IS_ERR(data->base))
 582                 return PTR_ERR(data->base);
 583
 584         wmt_desc.pins = data->pins;
 585         wmt_desc.npins = data->npins;
 586
 587         data->gpio_chip = wmt_gpio_chip;
 588         data->gpio_chip.dev = &pdev->dev;
 589         data->gpio_chip.of_node = pdev->dev.of_node;
 590         data->gpio_chip.ngpio = data->nbanks * 32;
 591
 592         platform_set_drvdata(pdev, data);
 593
 594         data->dev = &pdev->dev;
 595
 596         data->pctl_dev = pinctrl_register(&wmt_desc, &pdev->dev, data);
 597         if (!data->pctl_dev) {
 598                 dev_err(&pdev->dev, "Failed to register pinctrl\n");
 599                 return -EINVAL;
 600         }
 601
 602         err = gpiochip_add(&data->gpio_chip);
 603         if (err) {
 604                 dev_err(&pdev->dev, "could not add GPIO chip\n");
 605                 goto fail_gpio;
 606         }
 607
 608         err = gpiochip_add_pin_range(&data->gpio_chip, dev_name(data->dev),
 609                                      0, 0, data->nbanks * 32);
 610         if (err)
 611                 goto fail_range;
 612
 613         dev_info(&pdev->dev, "Pin controller initialized\n");
 614
 615         return 0;
 616
 617 fail_range:
 618         gpiochip_remove(&data->gpio_chip);
 619 fail_gpio:
 620         pinctrl_unregister(data->pctl_dev);
 621         return err;
 622 }
 623
 624 int wmt_pinctrl_remove(struct platform_device *pdev)
 625 {
 626         struct wmt_pinctrl_data *data = platform_get_drvdata(pdev);
 627
 628         gpiochip_remove(&data->gpio_chip);
 629         pinctrl_unregister(data->pctl_dev);
 630
 631         return 0;
 632 }