drivers/pinctrl/core.c

   1 /*
   2  * Core driver for the pin control subsystem
   3  *
   4  * Copyright (C) 2011-2012 ST-Ericsson SA
   5  * Written on behalf of Linaro for ST-Ericsson
   6  * Based on bits of regulator core, gpio core and clk core
   7  *
   8  * Author: Linus Walleij <linus.walleij@linaro.org>
   9  *
  10  * Copyright (C) 2012 NVIDIA CORPORATION. All rights reserved.
  11  *
  12  * License terms: GNU General Public License (GPL) version 2
  13  */
  14 #define pr_fmt(fmt) "pinctrl core: " fmt
  15
  16 #include <linux/kernel.h>
  17 #include <linux/export.h>
  18 #include <linux/init.h>
  19 #include <linux/device.h>
  20 #include <linux/slab.h>
  21 #include <linux/err.h>
  22 #include <linux/list.h>
  23 #include <linux/sysfs.h>
  24 #include <linux/debugfs.h>
  25 #include <linux/seq_file.h>
  26 #include <linux/pinctrl/pinctrl.h>
  27 #include <linux/pinctrl/machine.h>
  28 #include "core.h"
  29 #include "pinmux.h"
  30 #include "pinconf.h"
  31
  32 /**
  33  * struct pinctrl_maps - a list item containing part of the mapping table
  34  * @node: mapping table list node
  35  * @maps: array of mapping table entries
  36  * @num_maps: the number of entries in @maps
  37  */
  38 struct pinctrl_maps {
  39         struct list_head node;
  40         struct pinctrl_map const *maps;
  41         unsigned num_maps;
  42 };
  43
  44 /* Mutex taken by all entry points */
  45 DEFINE_MUTEX(pinctrl_mutex);
  46
  47 /* Global list of pin control devices (struct pinctrl_dev) */
  48 static LIST_HEAD(pinctrldev_list);
  49
  50 /* List of pin controller handles (struct pinctrl) */
  51 static LIST_HEAD(pinctrl_list);
  52
  53 /* List of pinctrl maps (struct pinctrl_maps) */
  54 static LIST_HEAD(pinctrl_maps);
  55
  56 #define for_each_maps(_maps_node_, _i_, _map_) \
  57         list_for_each_entry(_maps_node_, &pinctrl_maps, node) \
  58                 for (_i_ = 0, _map_ = &_maps_node_->maps[_i_]; \
  59                         _i_ < _maps_node_->num_maps; \
  60                         i++, _map_ = &_maps_node_->maps[_i_])
  61
  62 const char *pinctrl_dev_get_name(struct pinctrl_dev *pctldev)
  63 {
  64         /* We're not allowed to register devices without name */
  65         return pctldev->desc->name;
  66 }
  67 EXPORT_SYMBOL_GPL(pinctrl_dev_get_name);
  68
  69 void *pinctrl_dev_get_drvdata(struct pinctrl_dev *pctldev)
  70 {
  71         return pctldev->driver_data;
  72 }
  73 EXPORT_SYMBOL_GPL(pinctrl_dev_get_drvdata);
  74
  75 /**
  76  * get_pinctrl_dev_from_devname() - look up pin controller device
  77  * @devname: the name of a device instance, as returned by dev_name()
  78  *
  79  * Looks up a pin control device matching a certain device name or pure device
  80  * pointer, the pure device pointer will take precedence.
  81  */
  82 struct pinctrl_dev *get_pinctrl_dev_from_devname(const char *devname)
  83 {
  84         struct pinctrl_dev *pctldev = NULL;
  85         bool found = false;
  86
  87         if (!devname)
  88                 return NULL;
  89
  90         list_for_each_entry(pctldev, &pinctrldev_list, node) {
  91                 if (!strcmp(dev_name(pctldev->dev), devname)) {
  92                         /* Matched on device name */
  93                         found = true;
  94                         break;
  95                 }
  96         }
  97
  98         return found ? pctldev : NULL;
  99 }
 100
 101 /**
 102  * pin_get_from_name() - look up a pin number from a name
 103  * @pctldev: the pin control device to lookup the pin on
 104  * @name: the name of the pin to look up
 105  */
 106 int pin_get_from_name(struct pinctrl_dev *pctldev, const char *name)
 107 {
 108         unsigned i, pin;
 109
 110         /* The pin number can be retrived from the pin controller descriptor */
 111         for (i = 0; i < pctldev->desc->npins; i++) {
 112                 struct pin_desc *desc;
 113
 114                 pin = pctldev->desc->pins[i].number;
 115                 desc = pin_desc_get(pctldev, pin);
 116                 /* Pin space may be sparse */
 117                 if (desc == NULL)
 118                         continue;
 119                 if (desc->name && !strcmp(name, desc->name))
 120                         return pin;
 121         }
 122
 123         return -EINVAL;
 124 }
 125
 126 /**
 127  * pin_is_valid() - check if pin exists on controller
 128  * @pctldev: the pin control device to check the pin on
 129  * @pin: pin to check, use the local pin controller index number
 130  *
 131  * This tells us whether a certain pin exist on a certain pin controller or
 132  * not. Pin lists may be sparse, so some pins may not exist.
 133  */
 134 bool pin_is_valid(struct pinctrl_dev *pctldev, int pin)
 135 {
 136         struct pin_desc *pindesc;
 137
 138         if (pin < 0)
 139                 return false;
 140
 141         mutex_lock(&pinctrl_mutex);
 142         pindesc = pin_desc_get(pctldev, pin);
 143         mutex_unlock(&pinctrl_mutex);
 144
 145         return pindesc != NULL;
 146 }
 147 EXPORT_SYMBOL_GPL(pin_is_valid);
 148
 149 /* Deletes a range of pin descriptors */
 150 static void pinctrl_free_pindescs(struct pinctrl_dev *pctldev,
 151                                   const struct pinctrl_pin_desc *pins,
 152                                   unsigned num_pins)
 153 {
 154         int i;
 155
 156         for (i = 0; i < num_pins; i++) {
 157                 struct pin_desc *pindesc;
 158
 159                 pindesc = radix_tree_lookup(&pctldev->pin_desc_tree,
 160                                             pins[i].number);
 161                 if (pindesc != NULL) {
 162                         radix_tree_delete(&pctldev->pin_desc_tree,
 163                                           pins[i].number);
 164                         if (pindesc->dynamic_name)
 165                                 kfree(pindesc->name);
 166                 }
 167                 kfree(pindesc);
 168         }
 169 }
 170
 171 static int pinctrl_register_one_pin(struct pinctrl_dev *pctldev,
 172                                     unsigned number, const char *name)
 173 {
 174         struct pin_desc *pindesc;
 175
 176         pindesc = pin_desc_get(pctldev, number);
 177         if (pindesc != NULL) {
 178                 pr_err("pin %d already registered on %s\n", number,
 179                        pctldev->desc->name);
 180                 return -EINVAL;
 181         }
 182
 183         pindesc = kzalloc(sizeof(*pindesc), GFP_KERNEL);
 184         if (pindesc == NULL) {
 185                 dev_err(pctldev->dev, "failed to alloc struct pin_desc\n");
 186                 return -ENOMEM;
 187         }
 188
 189         /* Set owner */
 190         pindesc->pctldev = pctldev;
 191
 192         /* Copy basic pin info */
 193         if (name) {
 194                 pindesc->name = name;
 195         } else {
 196                 pindesc->name = kasprintf(GFP_KERNEL, "PIN%u", number);
 197                 if (pindesc->name == NULL)
 198                         return -ENOMEM;
 199                 pindesc->dynamic_name = true;
 200         }
 201
 202         radix_tree_insert(&pctldev->pin_desc_tree, number, pindesc);
 203         pr_debug("registered pin %d (%s) on %s\n",
 204                  number, pindesc->name, pctldev->desc->name);
 205         return 0;
 206 }
 207
 208 static int pinctrl_register_pins(struct pinctrl_dev *pctldev,
 209                                  struct pinctrl_pin_desc const *pins,
 210                                  unsigned num_descs)
 211 {
 212         unsigned i;
 213         int ret = 0;
 214
 215         for (i = 0; i < num_descs; i++) {
 216                 ret = pinctrl_register_one_pin(pctldev,
 217                                                pins[i].number, pins[i].name);
 218                 if (ret)
 219                         return ret;
 220         }
 221
 222         return 0;
 223 }
 224
 225 /**
 226  * pinctrl_match_gpio_range() - check if a certain GPIO pin is in range
 227  * @pctldev: pin controller device to check
 228  * @gpio: gpio pin to check taken from the global GPIO pin space
 229  *
 230  * Tries to match a GPIO pin number to the ranges handled by a certain pin
 231  * controller, return the range or NULL
 232  */
 233 static struct pinctrl_gpio_range *
 234 pinctrl_match_gpio_range(struct pinctrl_dev *pctldev, unsigned gpio)
 235 {
 236         struct pinctrl_gpio_range *range = NULL;
 237
 238         /* Loop over the ranges */
 239         list_for_each_entry(range, &pctldev->gpio_ranges, node) {
 240                 /* Check if we're in the valid range */
 241                 if (gpio >= range->base &&
 242                     gpio < range->base + range->npins) {
 243                         return range;
 244                 }
 245         }
 246
 247         return NULL;
 248 }
 249
 250 /**
 251  * pinctrl_get_device_gpio_range() - find device for GPIO range
 252  * @gpio: the pin to locate the pin controller for
 253  * @outdev: the pin control device if found
 254  * @outrange: the GPIO range if found
 255  *
 256  * Find the pin controller handling a certain GPIO pin from the pinspace of
 257  * the GPIO subsystem, return the device and the matching GPIO range. Returns
 258  * negative if the GPIO range could not be found in any device.
 259  */
 260 static int pinctrl_get_device_gpio_range(unsigned gpio,
 261                                          struct pinctrl_dev **outdev,
 262                                          struct pinctrl_gpio_range **outrange)
 263 {
 264         struct pinctrl_dev *pctldev = NULL;
 265
 266         /* Loop over the pin controllers */
 267         list_for_each_entry(pctldev, &pinctrldev_list, node) {
 268                 struct pinctrl_gpio_range *range;
 269
 270                 range = pinctrl_match_gpio_range(pctldev, gpio);
 271                 if (range != NULL) {
 272                         *outdev = pctldev;
 273                         *outrange = range;
 274                         return 0;
 275                 }
 276         }
 277
 278         return -EINVAL;
 279 }
 280
 281 /**
 282  * pinctrl_add_gpio_range() - register a GPIO range for a controller
 283  * @pctldev: pin controller device to add the range to
 284  * @range: the GPIO range to add
 285  *
 286  * This adds a range of GPIOs to be handled by a certain pin controller. Call
 287  * this to register handled ranges after registering your pin controller.
 288  */
 289 void pinctrl_add_gpio_range(struct pinctrl_dev *pctldev,
 290                             struct pinctrl_gpio_range *range)
 291 {
 292         mutex_lock(&pinctrl_mutex);
 293         list_add_tail(&range->node, &pctldev->gpio_ranges);
 294         mutex_unlock(&pinctrl_mutex);
 295 }
 296 EXPORT_SYMBOL_GPL(pinctrl_add_gpio_range);
 297
 298 /**
 299  * pinctrl_remove_gpio_range() - remove a range of GPIOs fro a pin controller
 300  * @pctldev: pin controller device to remove the range from
 301  * @range: the GPIO range to remove
 302  */
 303 void pinctrl_remove_gpio_range(struct pinctrl_dev *pctldev,
 304                                struct pinctrl_gpio_range *range)
 305 {
 306         mutex_lock(&pinctrl_mutex);
 307         list_del(&range->node);
 308         mutex_unlock(&pinctrl_mutex);
 309 }
 310 EXPORT_SYMBOL_GPL(pinctrl_remove_gpio_range);
 311
 312 /**
 313  * pinctrl_get_group_selector() - returns the group selector for a group
 314  * @pctldev: the pin controller handling the group
 315  * @pin_group: the pin group to look up
 316  */
 317 int pinctrl_get_group_selector(struct pinctrl_dev *pctldev,
 318                                const char *pin_group)
 319 {
 320         const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
 321         unsigned group_selector = 0;
 322
 323         while (pctlops->list_groups(pctldev, group_selector) >= 0) {
 324                 const char *gname = pctlops->get_group_name(pctldev,
 325                                                             group_selector);
 326                 if (!strcmp(gname, pin_group)) {
 327                         dev_dbg(pctldev->dev,
 328                                 "found group selector %u for %s\n",
 329                                 group_selector,
 330                                 pin_group);
 331                         return group_selector;
 332                 }
 333
 334                 group_selector++;
 335         }
 336
 337         dev_err(pctldev->dev, "does not have pin group %s\n",
 338                 pin_group);
 339
 340         return -EINVAL;
 341 }
 342
 343 /**
 344  * pinctrl_request_gpio() - request a single pin to be used in as GPIO
 345  * @gpio: the GPIO pin number from the GPIO subsystem number space
 346  *
 347  * This function should *ONLY* be used from gpiolib-based GPIO drivers,
 348  * as part of their gpio_request() semantics, platforms and individual drivers
 349  * shall *NOT* request GPIO pins to be muxed in.
 350  */
 351 int pinctrl_request_gpio(unsigned gpio)
 352 {
 353         struct pinctrl_dev *pctldev;
 354         struct pinctrl_gpio_range *range;
 355         int ret;
 356         int pin;
 357
 358         mutex_lock(&pinctrl_mutex);
 359
 360         ret = pinctrl_get_device_gpio_range(gpio, &pctldev, &range);
 361         if (ret) {
 362                 mutex_unlock(&pinctrl_mutex);
 363                 return -EINVAL;
 364         }
 365
 366         /* Convert to the pin controllers number space */
 367         pin = gpio - range->base + range->pin_base;
 368
 369         ret = pinmux_request_gpio(pctldev, range, pin, gpio);
 370
 371         mutex_unlock(&pinctrl_mutex);
 372         return ret;
 373 }
 374 EXPORT_SYMBOL_GPL(pinctrl_request_gpio);
 375
 376 /**
 377  * pinctrl_free_gpio() - free control on a single pin, currently used as GPIO
 378  * @gpio: the GPIO pin number from the GPIO subsystem number space
 379  *
 380  * This function should *ONLY* be used from gpiolib-based GPIO drivers,
 381  * as part of their gpio_free() semantics, platforms and individual drivers
 382  * shall *NOT* request GPIO pins to be muxed out.
 383  */
 384 void pinctrl_free_gpio(unsigned gpio)
 385 {
 386         struct pinctrl_dev *pctldev;
 387         struct pinctrl_gpio_range *range;
 388         int ret;
 389         int pin;
 390
 391         mutex_lock(&pinctrl_mutex);
 392
 393         ret = pinctrl_get_device_gpio_range(gpio, &pctldev, &range);
 394         if (ret) {
 395                 mutex_unlock(&pinctrl_mutex);
 396                 return;
 397         }
 398
 399         /* Convert to the pin controllers number space */
 400         pin = gpio - range->base + range->pin_base;
 401
 402         pinmux_free_gpio(pctldev, pin, range);
 403
 404         mutex_unlock(&pinctrl_mutex);
 405 }
 406 EXPORT_SYMBOL_GPL(pinctrl_free_gpio);
 407
 408 static int pinctrl_gpio_direction(unsigned gpio, bool input)
 409 {
 410         struct pinctrl_dev *pctldev;
 411         struct pinctrl_gpio_range *range;
 412         int ret;
 413         int pin;
 414
 415         ret = pinctrl_get_device_gpio_range(gpio, &pctldev, &range);
 416         if (ret)
 417                 return ret;
 418
 419         /* Convert to the pin controllers number space */
 420         pin = gpio - range->base + range->pin_base;
 421
 422         return pinmux_gpio_direction(pctldev, range, pin, input);
 423 }
 424
 425 /**
 426  * pinctrl_gpio_direction_input() - request a GPIO pin to go into input mode
 427  * @gpio: the GPIO pin number from the GPIO subsystem number space
 428  *
 429  * This function should *ONLY* be used from gpiolib-based GPIO drivers,
 430  * as part of their gpio_direction_input() semantics, platforms and individual
 431  * drivers shall *NOT* touch pin control GPIO calls.
 432  */
 433 int pinctrl_gpio_direction_input(unsigned gpio)
 434 {
 435         int ret;
 436         mutex_lock(&pinctrl_mutex);
 437         ret = pinctrl_gpio_direction(gpio, true);
 438         mutex_unlock(&pinctrl_mutex);
 439         return ret;
 440 }
 441 EXPORT_SYMBOL_GPL(pinctrl_gpio_direction_input);
 442
 443 /**
 444  * pinctrl_gpio_direction_output() - request a GPIO pin to go into output mode
 445  * @gpio: the GPIO pin number from the GPIO subsystem number space
 446  *
 447  * This function should *ONLY* be used from gpiolib-based GPIO drivers,
 448  * as part of their gpio_direction_output() semantics, platforms and individual
 449  * drivers shall *NOT* touch pin control GPIO calls.
 450  */
 451 int pinctrl_gpio_direction_output(unsigned gpio)
 452 {
 453         int ret;
 454         mutex_lock(&pinctrl_mutex);
 455         ret = pinctrl_gpio_direction(gpio, false);
 456         mutex_unlock(&pinctrl_mutex);
 457         return ret;
 458 }
 459 EXPORT_SYMBOL_GPL(pinctrl_gpio_direction_output);
 460
 461 static struct pinctrl_state *find_state(struct pinctrl *p,
 462                                         const char *name)
 463 {
 464         struct pinctrl_state *state;
 465
 466         list_for_each_entry(state, &p->states, node)
 467                 if (!strcmp(state->name, name))
 468                         return state;
 469
 470         return NULL;
 471 }
 472
 473 static struct pinctrl_state *create_state(struct pinctrl *p,
 474                                           const char *name)
 475 {
 476         struct pinctrl_state *state;
 477
 478         state = kzalloc(sizeof(*state), GFP_KERNEL);
 479         if (state == NULL) {
 480                 dev_err(p->dev,
 481                         "failed to alloc struct pinctrl_state\n");
 482                 return ERR_PTR(-ENOMEM);
 483         }
 484
 485         state->name = name;
 486         INIT_LIST_HEAD(&state->settings);
 487
 488         list_add_tail(&state->node, &p->states);
 489
 490         return state;
 491 }
 492
 493 static int add_setting(struct pinctrl *p, struct pinctrl_map const *map)
 494 {
 495         struct pinctrl_state *state;
 496         struct pinctrl_setting *setting;
 497         int ret;
 498
 499         state = find_state(p, map->name);
 500         if (!state)
 501                 state = create_state(p, map->name);
 502         if (IS_ERR(state))
 503                 return PTR_ERR(state);
 504
 505         if (map->type == PIN_MAP_TYPE_DUMMY_STATE)
 506                 return 0;
 507
 508         setting = kzalloc(sizeof(*setting), GFP_KERNEL);
 509         if (setting == NULL) {
 510                 dev_err(p->dev,
 511                         "failed to alloc struct pinctrl_setting\n");
 512                 return -ENOMEM;
 513         }
 514
 515         setting->type = map->type;
 516
 517         setting->pctldev = get_pinctrl_dev_from_devname(map->ctrl_dev_name);
 518         if (setting->pctldev == NULL) {
 519                 dev_err(p->dev, "unknown pinctrl device %s in map entry",
 520                         map->ctrl_dev_name);
 521                 kfree(setting);
 522                 /* Eventually, this should trigger deferred probe */
 523                 return -ENODEV;
 524         }
 525
 526         switch (map->type) {
 527         case PIN_MAP_TYPE_MUX_GROUP:
 528                 ret = pinmux_map_to_setting(map, setting);
 529                 break;
 530         case PIN_MAP_TYPE_CONFIGS_PIN:
 531         case PIN_MAP_TYPE_CONFIGS_GROUP:
 532                 ret = pinconf_map_to_setting(map, setting);
 533                 break;
 534         default:
 535                 ret = -EINVAL;
 536                 break;
 537         }
 538         if (ret < 0) {
 539                 kfree(setting);
 540                 return ret;
 541         }
 542
 543         list_add_tail(&setting->node, &state->settings);
 544
 545         return 0;
 546 }
 547
 548 static struct pinctrl *find_pinctrl(struct device *dev)
 549 {
 550         struct pinctrl *p;
 551
 552         list_for_each_entry(p, &pinctrl_list, node)
 553                 if (p->dev == dev)
 554                         return p;
 555
 556         return NULL;
 557 }
 558
 559 static void pinctrl_put_locked(struct pinctrl *p, bool inlist);
 560
 561 static struct pinctrl *create_pinctrl(struct device *dev)
 562 {
 563         struct pinctrl *p;
 564         const char *devname;
 565         struct pinctrl_maps *maps_node;
 566         int i;
 567         struct pinctrl_map const *map;
 568         int ret;
 569
 570         /*
 571          * create the state cookie holder struct pinctrl for each
 572          * mapping, this is what consumers will get when requesting
 573          * a pin control handle with pinctrl_get()
 574          */
 575         p = kzalloc(sizeof(*p), GFP_KERNEL);
 576         if (p == NULL) {
 577                 dev_err(dev, "failed to alloc struct pinctrl\n");
 578                 return ERR_PTR(-ENOMEM);
 579         }
 580         p->dev = dev;
 581         INIT_LIST_HEAD(&p->states);
 582
 583         devname = dev_name(dev);
 584
 585         /* Iterate over the pin control maps to locate the right ones */
 586         for_each_maps(maps_node, i, map) {
 587                 /* Map must be for this device */
 588                 if (strcmp(map->dev_name, devname))
 589                         continue;
 590
 591                 ret = add_setting(p, map);
 592                 if (ret < 0) {
 593                         pinctrl_put_locked(p, false);
 594                         return ERR_PTR(ret);
 595                 }
 596         }
 597
 598         /* Add the pinmux to the global list */
 599         list_add_tail(&p->node, &pinctrl_list);
 600
 601         return p;
 602 }
 603
 604 static struct pinctrl *pinctrl_get_locked(struct device *dev)
 605 {
 606         struct pinctrl *p;
 607
 608         if (WARN_ON(!dev))
 609                 return ERR_PTR(-EINVAL);
 610
 611         p = find_pinctrl(dev);
 612         if (p != NULL)
 613                 return ERR_PTR(-EBUSY);
 614
 615         p = create_pinctrl(dev);
 616         if (IS_ERR(p))
 617                 return p;
 618
 619         return p;
 620 }
 621
 622 /**
 623  * pinctrl_get() - retrieves the pinctrl handle for a device
 624  * @dev: the device to obtain the handle for
 625  */
 626 struct pinctrl *pinctrl_get(struct device *dev)
 627 {
 628         struct pinctrl *p;
 629
 630         mutex_lock(&pinctrl_mutex);
 631         p = pinctrl_get_locked(dev);
 632         mutex_unlock(&pinctrl_mutex);
 633
 634         return p;
 635 }
 636 EXPORT_SYMBOL_GPL(pinctrl_get);
 637
 638 static void pinctrl_put_locked(struct pinctrl *p, bool inlist)
 639 {
 640         struct pinctrl_state *state, *n1;
 641         struct pinctrl_setting *setting, *n2;
 642
 643         list_for_each_entry_safe(state, n1, &p->states, node) {
 644                 list_for_each_entry_safe(setting, n2, &state->settings, node) {
 645                         switch (setting->type) {
 646                         case PIN_MAP_TYPE_MUX_GROUP:
 647                                 if (state == p->state)
 648                                         pinmux_disable_setting(setting);
 649                                 pinmux_free_setting(setting);
 650                                 break;
 651                         case PIN_MAP_TYPE_CONFIGS_PIN:
 652                         case PIN_MAP_TYPE_CONFIGS_GROUP:
 653                                 pinconf_free_setting(setting);
 654                                 break;
 655                         default:
 656                                 break;
 657                         }
 658                         list_del(&setting->node);
 659                         kfree(setting);
 660                 }
 661                 list_del(&state->node);
 662                 kfree(state);
 663         }
 664
 665         if (inlist)
 666                 list_del(&p->node);
 667         kfree(p);
 668 }
 669
 670 /**
 671  * pinctrl_put() - release a previously claimed pinctrl handle
 672  * @p: the pinctrl handle to release
 673  */
 674 void pinctrl_put(struct pinctrl *p)
 675 {
 676         mutex_lock(&pinctrl_mutex);
 677         pinctrl_put_locked(p, true);
 678         mutex_unlock(&pinctrl_mutex);
 679 }
 680 EXPORT_SYMBOL_GPL(pinctrl_put);
 681
 682 static struct pinctrl_state *pinctrl_lookup_state_locked(struct pinctrl *p,
 683                                                          const char *name)
 684 {
 685         struct pinctrl_state *state;
 686
 687         state = find_state(p, name);
 688         if (!state)
 689                 return ERR_PTR(-ENODEV);
 690
 691         return state;
 692 }
 693
 694 /**
 695  * pinctrl_lookup_state() - retrieves a state handle from a pinctrl handle
 696  * @p: the pinctrl handle to retrieve the state from
 697  * @name: the state name to retrieve
 698  */
 699 struct pinctrl_state *pinctrl_lookup_state(struct pinctrl *p, const char *name)
 700 {
 701         struct pinctrl_state *s;
 702
 703         mutex_lock(&pinctrl_mutex);
 704         s = pinctrl_lookup_state_locked(p, name);
 705         mutex_unlock(&pinctrl_mutex);
 706
 707         return s;
 708 }
 709 EXPORT_SYMBOL_GPL(pinctrl_lookup_state);
 710
 711 static int pinctrl_select_state_locked(struct pinctrl *p,
 712                                        struct pinctrl_state *state)
 713 {
 714         struct pinctrl_setting *setting, *setting2;
 715         int ret;
 716
 717         if (p->state == state)
 718                 return 0;
 719
 720         if (p->state) {
 721                 /*
 722                  * The set of groups with a mux configuration in the old state
 723                  * may not be identical to the set of groups with a mux setting
 724                  * in the new state. While this might be unusual, it's entirely
 725                  * possible for the "user"-supplied mapping table to be written
 726                  * that way. For each group that was configured in the old state
 727                  * but not in the new state, this code puts that group into a
 728                  * safe/disabled state.
 729                  */
 730                 list_for_each_entry(setting, &p->state->settings, node) {
 731                         bool found = false;
 732                         if (setting->type != PIN_MAP_TYPE_MUX_GROUP)
 733                                 continue;
 734                         list_for_each_entry(setting2, &state->settings, node) {
 735                                 if (setting2->type != PIN_MAP_TYPE_MUX_GROUP)
 736                                         continue;
 737                                 if (setting2->data.mux.group ==
 738                                                 setting->data.mux.group) {
 739                                         found = true;
 740                                         break;
 741                                 }
 742                         }
 743                         if (!found)
 744                                 pinmux_disable_setting(setting);
 745                 }
 746         }
 747
 748         p->state = state;
 749
 750         /* Apply all the settings for the new state */
 751         list_for_each_entry(setting, &state->settings, node) {
 752                 switch (setting->type) {
 753                 case PIN_MAP_TYPE_MUX_GROUP:
 754                         ret = pinmux_enable_setting(setting);
 755                         break;
 756                 case PIN_MAP_TYPE_CONFIGS_PIN:
 757                 case PIN_MAP_TYPE_CONFIGS_GROUP:
 758                         ret = pinconf_apply_setting(setting);
 759                         break;
 760                 default:
 761                         ret = -EINVAL;
 762                         break;
 763                 }
 764                 if (ret < 0) {
 765                         /* FIXME: Difficult to return to prev state */
 766                         return ret;
 767                 }
 768         }
 769
 770         return 0;
 771 }
 772
 773 /**
 774  * pinctrl_select() - select/activate/program a pinctrl state to HW
 775  * @p: the pinctrl handle for the device that requests configuratio
 776  * @state: the state handle to select/activate/program
 777  */
 778 int pinctrl_select_state(struct pinctrl *p, struct pinctrl_state *state)
 779 {
 780         int ret;
 781
 782         mutex_lock(&pinctrl_mutex);
 783         ret = pinctrl_select_state_locked(p, state);
 784         mutex_unlock(&pinctrl_mutex);
 785
 786         return ret;
 787 }
 788 EXPORT_SYMBOL_GPL(pinctrl_select_state);
 789
 790 /**
 791  * pinctrl_register_mappings() - register a set of pin controller mappings
 792  * @maps: the pincontrol mappings table to register. This should probably be
 793  *      marked with __initdata so it can be discarded after boot. This
 794  *      function will perform a shallow copy for the mapping entries.
 795  * @num_maps: the number of maps in the mapping table
 796  */
 797 int pinctrl_register_mappings(struct pinctrl_map const *maps,
 798                               unsigned num_maps)
 799 {
 800         int i, ret;
 801         struct pinctrl_maps *maps_node;
 802
 803         pr_debug("add %d pinmux maps\n", num_maps);
 804
 805         /* First sanity check the new mapping */
 806         for (i = 0; i < num_maps; i++) {
 807                 if (!maps[i].dev_name) {
 808                         pr_err("failed to register map %s (%d): no device given\n",
 809                                maps[i].name, i);
 810                         return -EINVAL;
 811                 }
 812
 813                 if (!maps[i].name) {
 814                         pr_err("failed to register map %d: no map name given\n",
 815                                i);
 816                         return -EINVAL;
 817                 }
 818
 819                 if (maps[i].type != PIN_MAP_TYPE_DUMMY_STATE &&
 820                                 !maps[i].ctrl_dev_name) {
 821                         pr_err("failed to register map %s (%d): no pin control device given\n",
 822                                maps[i].name, i);
 823                         return -EINVAL;
 824                 }
 825
 826                 switch (maps[i].type) {
 827                 case PIN_MAP_TYPE_DUMMY_STATE:
 828                         break;
 829                 case PIN_MAP_TYPE_MUX_GROUP:
 830                         ret = pinmux_validate_map(&maps[i], i);
 831                         if (ret < 0)
 832                                 return 0;
 833                         break;
 834                 case PIN_MAP_TYPE_CONFIGS_PIN:
 835                 case PIN_MAP_TYPE_CONFIGS_GROUP:
 836                         ret = pinconf_validate_map(&maps[i], i);
 837                         if (ret < 0)
 838                                 return 0;
 839                         break;
 840                 default:
 841                         pr_err("failed to register map %s (%d): invalid type given\n",
 842                                maps[i].name, i);
 843                         return -EINVAL;
 844                 }
 845         }
 846
 847         maps_node = kzalloc(sizeof(*maps_node), GFP_KERNEL);
 848         if (!maps_node) {
 849                 pr_err("failed to alloc struct pinctrl_maps\n");
 850                 return -ENOMEM;
 851         }
 852
 853         maps_node->num_maps = num_maps;
 854         maps_node->maps = kmemdup(maps, sizeof(*maps) * num_maps, GFP_KERNEL);
 855         if (!maps_node->maps) {
 856                 pr_err("failed to duplicate mapping table\n");
 857                 kfree(maps_node);
 858                 return -ENOMEM;
 859         }
 860
 861         mutex_lock(&pinctrl_mutex);
 862         list_add_tail(&maps_node->node, &pinctrl_maps);
 863         mutex_unlock(&pinctrl_mutex);
 864
 865         return 0;
 866 }
 867
 868 #ifdef CONFIG_DEBUG_FS
 869
 870 static int pinctrl_pins_show(struct seq_file *s, void *what)
 871 {
 872         struct pinctrl_dev *pctldev = s->private;
 873         const struct pinctrl_ops *ops = pctldev->desc->pctlops;
 874         unsigned i, pin;
 875
 876         seq_printf(s, "registered pins: %d\n", pctldev->desc->npins);
 877
 878         mutex_lock(&pinctrl_mutex);
 879
 880         /* The pin number can be retrived from the pin controller descriptor */
 881         for (i = 0; i < pctldev->desc->npins; i++) {
 882                 struct pin_desc *desc;
 883
 884                 pin = pctldev->desc->pins[i].number;
 885                 desc = pin_desc_get(pctldev, pin);
 886                 /* Pin space may be sparse */
 887                 if (desc == NULL)
 888                         continue;
 889
 890                 seq_printf(s, "pin %d (%s) ", pin,
 891                            desc->name ? desc->name : "unnamed");
 892
 893                 /* Driver-specific info per pin */
 894                 if (ops->pin_dbg_show)
 895                         ops->pin_dbg_show(pctldev, s, pin);
 896
 897                 seq_puts(s, "\n");
 898         }
 899
 900         mutex_unlock(&pinctrl_mutex);
 901
 902         return 0;
 903 }
 904
 905 static int pinctrl_groups_show(struct seq_file *s, void *what)
 906 {
 907         struct pinctrl_dev *pctldev = s->private;
 908         const struct pinctrl_ops *ops = pctldev->desc->pctlops;
 909         unsigned selector = 0;
 910
 911         mutex_lock(&pinctrl_mutex);
 912
 913         seq_puts(s, "registered pin groups:\n");
 914         while (ops->list_groups(pctldev, selector) >= 0) {
 915                 const unsigned *pins;
 916                 unsigned num_pins;
 917                 const char *gname = ops->get_group_name(pctldev, selector);
 918                 int ret;
 919                 int i;
 920
 921                 ret = ops->get_group_pins(pctldev, selector,
 922                                           &pins, &num_pins);
 923                 if (ret)
 924                         seq_printf(s, "%s [ERROR GETTING PINS]\n",
 925                                    gname);
 926                 else {
 927                         seq_printf(s, "group: %s, pins = [ ", gname);
 928                         for (i = 0; i < num_pins; i++)
 929                                 seq_printf(s, "%d ", pins[i]);
 930                         seq_puts(s, "]\n");
 931                 }
 932                 selector++;
 933         }
 934
 935         mutex_unlock(&pinctrl_mutex);
 936
 937         return 0;
 938 }
 939
 940 static int pinctrl_gpioranges_show(struct seq_file *s, void *what)
 941 {
 942         struct pinctrl_dev *pctldev = s->private;
 943         struct pinctrl_gpio_range *range = NULL;
 944
 945         seq_puts(s, "GPIO ranges handled:\n");
 946
 947         mutex_lock(&pinctrl_mutex);
 948
 949         /* Loop over the ranges */
 950         list_for_each_entry(range, &pctldev->gpio_ranges, node) {
 951                 seq_printf(s, "%u: %s GPIOS [%u - %u] PINS [%u - %u]\n",
 952                            range->id, range->name,
 953                            range->base, (range->base + range->npins - 1),
 954                            range->pin_base,
 955                            (range->pin_base + range->npins - 1));
 956         }
 957
 958         mutex_unlock(&pinctrl_mutex);
 959
 960         return 0;
 961 }
 962
 963 static int pinctrl_devices_show(struct seq_file *s, void *what)
 964 {
 965         struct pinctrl_dev *pctldev;
 966
 967         seq_puts(s, "name [pinmux] [pinconf]\n");
 968
 969         mutex_lock(&pinctrl_mutex);
 970
 971         list_for_each_entry(pctldev, &pinctrldev_list, node) {
 972                 seq_printf(s, "%s ", pctldev->desc->name);
 973                 if (pctldev->desc->pmxops)
 974                         seq_puts(s, "yes ");
 975                 else
 976                         seq_puts(s, "no ");
 977                 if (pctldev->desc->confops)
 978                         seq_puts(s, "yes");
 979                 else
 980                         seq_puts(s, "no");
 981                 seq_puts(s, "\n");
 982         }
 983
 984         mutex_unlock(&pinctrl_mutex);
 985
 986         return 0;
 987 }
 988
 989 static inline const char *map_type(enum pinctrl_map_type type)
 990 {
 991         static const char * const names[] = {
 992                 "INVALID",
 993                 "DUMMY_STATE",
 994                 "MUX_GROUP",
 995                 "CONFIGS_PIN",
 996                 "CONFIGS_GROUP",
 997         };
 998
 999         if (type >= ARRAY_SIZE(names))
1000                 return "UNKNOWN";
1001
1002         return names[type];
1003 }
1004
1005 static int pinctrl_maps_show(struct seq_file *s, void *what)
1006 {
1007         struct pinctrl_maps *maps_node;
1008         int i;
1009         struct pinctrl_map const *map;
1010
1011         seq_puts(s, "Pinctrl maps:\n");
1012
1013         mutex_lock(&pinctrl_mutex);
1014
1015         for_each_maps(maps_node, i, map) {
1016                 seq_printf(s, "device %s\nstate %s\ntype %s (%d)\n",
1017                            map->dev_name, map->name, map_type(map->type),
1018                            map->type);
1019
1020                 if (map->type != PIN_MAP_TYPE_DUMMY_STATE)
1021                         seq_printf(s, "controlling device %s\n",
1022                                    map->ctrl_dev_name);
1023
1024                 switch (map->type) {
1025                 case PIN_MAP_TYPE_MUX_GROUP:
1026                         pinmux_show_map(s, map);
1027                         break;
1028                 case PIN_MAP_TYPE_CONFIGS_PIN:
1029                 case PIN_MAP_TYPE_CONFIGS_GROUP:
1030                         pinconf_show_map(s, map);
1031                         break;
1032                 default:
1033                         break;
1034                 }
1035
1036                 seq_printf(s, "\n");
1037         }
1038
1039         mutex_unlock(&pinctrl_mutex);
1040
1041         return 0;
1042 }
1043
1044 static int pinctrl_show(struct seq_file *s, void *what)
1045 {
1046         struct pinctrl *p;
1047         struct pinctrl_state *state;
1048         struct pinctrl_setting *setting;
1049
1050         seq_puts(s, "Requested pin control handlers their pinmux maps:\n");
1051
1052         mutex_lock(&pinctrl_mutex);
1053
1054         list_for_each_entry(p, &pinctrl_list, node) {
1055                 seq_printf(s, "device: %s current state: %s\n",
1056                            dev_name(p->dev),
1057                            p->state ? p->state->name : "none");
1058
1059                 list_for_each_entry(state, &p->states, node) {
1060                         seq_printf(s, "  state: %s\n", state->name);
1061
1062                         list_for_each_entry(setting, &state->settings, node) {
1063                                 struct pinctrl_dev *pctldev = setting->pctldev;
1064
1065                                 seq_printf(s, "    type: %s controller %s ",
1066                                            map_type(setting->type),
1067                                            pinctrl_dev_get_name(pctldev));
1068
1069                                 switch (setting->type) {
1070                                 case PIN_MAP_TYPE_MUX_GROUP:
1071                                         pinmux_show_setting(s, setting);
1072                                         break;
1073                                 case PIN_MAP_TYPE_CONFIGS_PIN:
1074                                 case PIN_MAP_TYPE_CONFIGS_GROUP:
1075                                         pinconf_show_setting(s, setting);
1076                                         break;
1077                                 default:
1078                                         break;
1079                                 }
1080                         }
1081                 }
1082         }
1083
1084         mutex_unlock(&pinctrl_mutex);
1085
1086         return 0;
1087 }
1088
1089 static int pinctrl_pins_open(struct inode *inode, struct file *file)
1090 {
1091         return single_open(file, pinctrl_pins_show, inode->i_private);
1092 }
1093
1094 static int pinctrl_groups_open(struct inode *inode, struct file *file)
1095 {
1096         return single_open(file, pinctrl_groups_show, inode->i_private);
1097 }
1098
1099 static int pinctrl_gpioranges_open(struct inode *inode, struct file *file)
1100 {
1101         return single_open(file, pinctrl_gpioranges_show, inode->i_private);
1102 }
1103
1104 static int pinctrl_devices_open(struct inode *inode, struct file *file)
1105 {
1106         return single_open(file, pinctrl_devices_show, NULL);
1107 }
1108
1109 static int pinctrl_maps_open(struct inode *inode, struct file *file)
1110 {
1111         return single_open(file, pinctrl_maps_show, NULL);
1112 }
1113
1114 static int pinctrl_open(struct inode *inode, struct file *file)
1115 {
1116         return single_open(file, pinctrl_show, NULL);
1117 }
1118
1119 static const struct file_operations pinctrl_pins_ops = {
1120         .open           = pinctrl_pins_open,
1121         .read           = seq_read,
1122         .llseek         = seq_lseek,
1123         .release        = single_release,
1124 };
1125
1126 static const struct file_operations pinctrl_groups_ops = {
1127         .open           = pinctrl_groups_open,
1128         .read           = seq_read,
1129         .llseek         = seq_lseek,
1130         .release        = single_release,
1131 };
1132
1133 static const struct file_operations pinctrl_gpioranges_ops = {
1134         .open           = pinctrl_gpioranges_open,
1135         .read           = seq_read,
1136         .llseek         = seq_lseek,
1137         .release        = single_release,
1138 };
1139
1140 static const struct file_operations pinctrl_devices_ops = {
1141         .open           = pinctrl_devices_open,
1142         .read           = seq_read,
1143         .llseek         = seq_lseek,
1144         .release        = single_release,
1145 };
1146
1147 static const struct file_operations pinctrl_maps_ops = {
1148         .open           = pinctrl_maps_open,
1149         .read           = seq_read,
1150         .llseek         = seq_lseek,
1151         .release        = single_release,
1152 };
1153
1154 static const struct file_operations pinctrl_ops = {
1155         .open           = pinctrl_open,
1156         .read           = seq_read,
1157         .llseek         = seq_lseek,
1158         .release        = single_release,
1159 };
1160
1161 static struct dentry *debugfs_root;
1162
1163 static void pinctrl_init_device_debugfs(struct pinctrl_dev *pctldev)
1164 {
1165         struct dentry *device_root;
1166
1167         device_root = debugfs_create_dir(dev_name(pctldev->dev),
1168                                          debugfs_root);
1169         pctldev->device_root = device_root;
1170
1171         if (IS_ERR(device_root) || !device_root) {
1172                 pr_warn("failed to create debugfs directory for %s\n",
1173                         dev_name(pctldev->dev));
1174                 return;
1175         }
1176         debugfs_create_file("pins", S_IFREG | S_IRUGO,
1177                             device_root, pctldev, &pinctrl_pins_ops);
1178         debugfs_create_file("pingroups", S_IFREG | S_IRUGO,
1179                             device_root, pctldev, &pinctrl_groups_ops);
1180         debugfs_create_file("gpio-ranges", S_IFREG | S_IRUGO,
1181                             device_root, pctldev, &pinctrl_gpioranges_ops);
1182         pinmux_init_device_debugfs(device_root, pctldev);
1183         pinconf_init_device_debugfs(device_root, pctldev);
1184 }
1185
1186 static void pinctrl_remove_device_debugfs(struct pinctrl_dev *pctldev)
1187 {
1188         debugfs_remove_recursive(pctldev->device_root);
1189 }
1190
1191 static void pinctrl_init_debugfs(void)
1192 {
1193         debugfs_root = debugfs_create_dir("pinctrl", NULL);
1194         if (IS_ERR(debugfs_root) || !debugfs_root) {
1195                 pr_warn("failed to create debugfs directory\n");
1196                 debugfs_root = NULL;
1197                 return;
1198         }
1199
1200         debugfs_create_file("pinctrl-devices", S_IFREG | S_IRUGO,
1201                             debugfs_root, NULL, &pinctrl_devices_ops);
1202         debugfs_create_file("pinctrl-maps", S_IFREG | S_IRUGO,
1203                             debugfs_root, NULL, &pinctrl_maps_ops);
1204         debugfs_create_file("pinctrl-handles", S_IFREG | S_IRUGO,
1205                             debugfs_root, NULL, &pinctrl_ops);
1206 }
1207
1208 #else /* CONFIG_DEBUG_FS */
1209
1210 static void pinctrl_init_device_debugfs(struct pinctrl_dev *pctldev)
1211 {
1212 }
1213
1214 static void pinctrl_init_debugfs(void)
1215 {
1216 }
1217
1218 static void pinctrl_remove_device_debugfs(struct pinctrl_dev *pctldev)
1219 {
1220 }
1221
1222 #endif
1223
1224 static int pinctrl_check_ops(struct pinctrl_dev *pctldev)
1225 {
1226         const struct pinctrl_ops *ops = pctldev->desc->pctlops;
1227
1228         if (!ops ||
1229             !ops->list_groups ||
1230             !ops->get_group_name ||
1231             !ops->get_group_pins)
1232                 return -EINVAL;
1233
1234         return 0;
1235 }
1236
1237 /**
1238  * pinctrl_register() - register a pin controller device
1239  * @pctldesc: descriptor for this pin controller
1240  * @dev: parent device for this pin controller
1241  * @driver_data: private pin controller data for this pin controller
1242  */
1243 struct pinctrl_dev *pinctrl_register(struct pinctrl_desc *pctldesc,
1244                                     struct device *dev, void *driver_data)
1245 {
1246         struct pinctrl_dev *pctldev;
1247         int ret;
1248
1249         if (pctldesc == NULL)
1250                 return NULL;
1251         if (pctldesc->name == NULL)
1252                 return NULL;
1253
1254         pctldev = kzalloc(sizeof(*pctldev), GFP_KERNEL);
1255         if (pctldev == NULL) {
1256                 dev_err(dev, "failed to alloc struct pinctrl_dev\n");
1257                 return NULL;
1258         }
1259
1260         /* Initialize pin control device struct */
1261         pctldev->owner = pctldesc->owner;
1262         pctldev->desc = pctldesc;
1263         pctldev->driver_data = driver_data;
1264         INIT_RADIX_TREE(&pctldev->pin_desc_tree, GFP_KERNEL);
1265         INIT_LIST_HEAD(&pctldev->gpio_ranges);
1266         pctldev->dev = dev;
1267
1268         /* check core ops for sanity */
1269         ret = pinctrl_check_ops(pctldev);
1270         if (ret) {
1271                 pr_err("%s pinctrl ops lacks necessary functions\n",
1272                         pctldesc->name);
1273                 goto out_err;
1274         }
1275
1276         /* If we're implementing pinmuxing, check the ops for sanity */
1277         if (pctldesc->pmxops) {
1278                 ret = pinmux_check_ops(pctldev);
1279                 if (ret) {
1280                         pr_err("%s pinmux ops lacks necessary functions\n",
1281                                pctldesc->name);
1282                         goto out_err;
1283                 }
1284         }
1285
1286         /* If we're implementing pinconfig, check the ops for sanity */
1287         if (pctldesc->confops) {
1288                 ret = pinconf_check_ops(pctldev);
1289                 if (ret) {
1290                         pr_err("%s pin config ops lacks necessary functions\n",
1291                                pctldesc->name);
1292                         goto out_err;
1293                 }
1294         }
1295
1296         /* Register all the pins */
1297         pr_debug("try to register %d pins on %s...\n",
1298                  pctldesc->npins, pctldesc->name);
1299         ret = pinctrl_register_pins(pctldev, pctldesc->pins, pctldesc->npins);
1300         if (ret) {
1301                 pr_err("error during pin registration\n");
1302                 pinctrl_free_pindescs(pctldev, pctldesc->pins,
1303                                       pctldesc->npins);
1304                 goto out_err;
1305         }
1306
1307         mutex_lock(&pinctrl_mutex);
1308
1309         list_add_tail(&pctldev->node, &pinctrldev_list);
1310
1311         pctldev->p = pinctrl_get_locked(pctldev->dev);
1312         if (!IS_ERR(pctldev->p)) {
1313                 struct pinctrl_state *s =
1314                         pinctrl_lookup_state_locked(pctldev->p,
1315                                                     PINCTRL_STATE_DEFAULT);
1316                 if (!IS_ERR(s))
1317                         pinctrl_select_state_locked(pctldev->p, s);
1318         }
1319
1320         mutex_unlock(&pinctrl_mutex);
1321
1322         pinctrl_init_device_debugfs(pctldev);
1323
1324         return pctldev;
1325
1326 out_err:
1327         kfree(pctldev);
1328         return NULL;
1329 }
1330 EXPORT_SYMBOL_GPL(pinctrl_register);
1331
1332 /**
1333  * pinctrl_unregister() - unregister pinmux
1334  * @pctldev: pin controller to unregister
1335  *
1336  * Called by pinmux drivers to unregister a pinmux.
1337  */
1338 void pinctrl_unregister(struct pinctrl_dev *pctldev)
1339 {
1340         if (pctldev == NULL)
1341                 return;
1342
1343         pinctrl_remove_device_debugfs(pctldev);
1344
1345         mutex_lock(&pinctrl_mutex);
1346
1347         if (!IS_ERR(pctldev->p))
1348                 pinctrl_put_locked(pctldev->p, true);
1349
1350         /* TODO: check that no pinmuxes are still active? */
1351         list_del(&pctldev->node);
1352         /* Destroy descriptor tree */
1353         pinctrl_free_pindescs(pctldev, pctldev->desc->pins,
1354                               pctldev->desc->npins);
1355         kfree(pctldev);
1356
1357         mutex_unlock(&pinctrl_mutex);
1358 }
1359 EXPORT_SYMBOL_GPL(pinctrl_unregister);
1360
1361 static int __init pinctrl_init(void)
1362 {
1363         pr_info("initialized pinctrl subsystem\n");
1364         pinctrl_init_debugfs();
1365         return 0;
1366 }
1367
1368 /* init early since many drivers really need to initialized pinmux early */
1369 core_initcall(pinctrl_init);