drivers/pinctrl/pinmux.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Core driver for the pin muxing portions of the pin control subsystem
   4  *
   5  * Copyright (C) 2011-2012 ST-Ericsson SA
   6  * Written on behalf of Linaro for ST-Ericsson
   7  * Based on bits of regulator core, gpio core and clk core
   8  *
   9  * Author: Linus Walleij <linus.walleij@linaro.org>
  10  *
  11  * Copyright (C) 2012 NVIDIA CORPORATION. All rights reserved.
  12  */
  13 #define pr_fmt(fmt) "pinmux core: " fmt
  14
  15 #include <linux/kernel.h>
  16 #include <linux/module.h>
  17 #include <linux/init.h>
  18 #include <linux/device.h>
  19 #include <linux/slab.h>
  20 #include <linux/radix-tree.h>
  21 #include <linux/err.h>
  22 #include <linux/list.h>
  23 #include <linux/string.h>
  24 #include <linux/debugfs.h>
  25 #include <linux/seq_file.h>
  26 #include <linux/pinctrl/machine.h>
  27 #include <linux/pinctrl/pinmux.h>
  28 #include "core.h"
  29 #include "pinmux.h"
  30
  31 int pinmux_check_ops(struct pinctrl_dev *pctldev)
  32 {
  33         const struct pinmux_ops *ops = pctldev->desc->pmxops;
  34         unsigned nfuncs;
  35         unsigned selector = 0;
  36
  37         /* Check that we implement required operations */
  38         if (!ops ||
  39             !ops->get_functions_count ||
  40             !ops->get_function_name ||
  41             !ops->get_function_groups ||
  42             !ops->set_mux) {
  43                 dev_err(pctldev->dev, "pinmux ops lacks necessary functions\n");
  44                 return -EINVAL;
  45         }
  46         /* Check that all functions registered have names */
  47         nfuncs = ops->get_functions_count(pctldev);
  48         while (selector < nfuncs) {
  49                 const char *fname = ops->get_function_name(pctldev,
  50                                                            selector);
  51                 if (!fname) {
  52                         dev_err(pctldev->dev, "pinmux ops has no name for function%u\n",
  53                                 selector);
  54                         return -EINVAL;
  55                 }
  56                 selector++;
  57         }
  58
  59         return 0;
  60 }
  61
  62 int pinmux_validate_map(const struct pinctrl_map *map, int i)
  63 {
  64         if (!map->data.mux.function) {
  65                 pr_err("failed to register map %s (%d): no function given\n",
  66                        map->name, i);
  67                 return -EINVAL;
  68         }
  69
  70         return 0;
  71 }
  72
  73 /**
  74  * pinmux_can_be_used_for_gpio() - check if a specific pin
  75  *      is either muxed to a different function or used as gpio.
  76  *
  77  * @pin: the pin number in the global pin space
  78  *
  79  * Controllers not defined as strict will always return true,
  80  * menaning that the gpio can be used.
  81  */
  82 bool pinmux_can_be_used_for_gpio(struct pinctrl_dev *pctldev, unsigned pin)
  83 {
  84         struct pin_desc *desc = pin_desc_get(pctldev, pin);
  85         const struct pinmux_ops *ops = pctldev->desc->pmxops;
  86
  87         /* Can't inspect pin, assume it can be used */
  88         if (!desc || !ops)
  89                 return true;
  90
  91         if (ops->strict && desc->mux_usecount)
  92                 return false;
  93
  94         return !(ops->strict && !!desc->gpio_owner);
  95 }
  96
  97 /**
  98  * pin_request() - request a single pin to be muxed in, typically for GPIO
  99  * @pin: the pin number in the global pin space
 100  * @owner: a representation of the owner of this pin; typically the device
 101  *      name that controls its mux function, or the requested GPIO name
 102  * @gpio_range: the range matching the GPIO pin if this is a request for a
 103  *      single GPIO pin
 104  */
 105 static int pin_request(struct pinctrl_dev *pctldev,
 106                        int pin, const char *owner,
 107                        struct pinctrl_gpio_range *gpio_range)
 108 {
 109         struct pin_desc *desc;
 110         const struct pinmux_ops *ops = pctldev->desc->pmxops;
 111         int status = -EINVAL;
 112
 113         desc = pin_desc_get(pctldev, pin);
 114         if (desc == NULL) {
 115                 dev_err(pctldev->dev,
 116                         "pin %d is not registered so it cannot be requested\n",
 117                         pin);
 118                 goto out;
 119         }
 120
 121         dev_dbg(pctldev->dev, "request pin %d (%s) for %s\n",
 122                 pin, desc->name, owner);
 123
 124         if ((!gpio_range || ops->strict) &&
 125             desc->mux_usecount && strcmp(desc->mux_owner, owner)) {
 126                 dev_err(pctldev->dev,
 127                         "pin %s already requested by %s; cannot claim for %s\n",
 128                         desc->name, desc->mux_owner, owner);
 129                 goto out;
 130         }
 131
 132         if ((gpio_range || ops->strict) && desc->gpio_owner) {
 133                 dev_err(pctldev->dev,
 134                         "pin %s already requested by %s; cannot claim for %s\n",
 135                         desc->name, desc->gpio_owner, owner);
 136                 goto out;
 137         }
 138
 139         if (gpio_range) {
 140                 desc->gpio_owner = owner;
 141         } else {
 142                 desc->mux_usecount++;
 143                 if (desc->mux_usecount > 1)
 144                         return 0;
 145
 146                 desc->mux_owner = owner;
 147         }
 148
 149         /* Let each pin increase references to this module */
 150         if (!try_module_get(pctldev->owner)) {
 151                 dev_err(pctldev->dev,
 152                         "could not increase module refcount for pin %d\n",
 153                         pin);
 154                 status = -EINVAL;
 155                 goto out_free_pin;
 156         }
 157
 158         /*
 159          * If there is no kind of request function for the pin we just assume
 160          * we got it by default and proceed.
 161          */
 162         if (gpio_range && ops->gpio_request_enable)
 163                 /* This requests and enables a single GPIO pin */
 164                 status = ops->gpio_request_enable(pctldev, gpio_range, pin);
 165         else if (ops->request)
 166                 status = ops->request(pctldev, pin);
 167         else
 168                 status = 0;
 169
 170         if (status) {
 171                 dev_err(pctldev->dev, "request() failed for pin %d\n", pin);
 172                 module_put(pctldev->owner);
 173         }
 174
 175 out_free_pin:
 176         if (status) {
 177                 if (gpio_range) {
 178                         desc->gpio_owner = NULL;
 179                 } else {
 180                         desc->mux_usecount--;
 181                         if (!desc->mux_usecount)
 182                                 desc->mux_owner = NULL;
 183                 }
 184         }
 185 out:
 186         if (status)
 187                 dev_err(pctldev->dev, "pin-%d (%s) status %d\n",
 188                         pin, owner, status);
 189
 190         return status;
 191 }
 192
 193 /**
 194  * pin_free() - release a single muxed in pin so something else can be muxed
 195  * @pctldev: pin controller device handling this pin
 196  * @pin: the pin to free
 197  * @gpio_range: the range matching the GPIO pin if this is a request for a
 198  *      single GPIO pin
 199  *
 200  * This function returns a pointer to the previous owner. This is used
 201  * for callers that dynamically allocate an owner name so it can be freed
 202  * once the pin is free. This is done for GPIO request functions.
 203  */
 204 static const char *pin_free(struct pinctrl_dev *pctldev, int pin,
 205                             struct pinctrl_gpio_range *gpio_range)
 206 {
 207         const struct pinmux_ops *ops = pctldev->desc->pmxops;
 208         struct pin_desc *desc;
 209         const char *owner;
 210
 211         desc = pin_desc_get(pctldev, pin);
 212         if (desc == NULL) {
 213                 dev_err(pctldev->dev,
 214                         "pin is not registered so it cannot be freed\n");
 215                 return NULL;
 216         }
 217
 218         if (!gpio_range) {
 219                 /*
 220                  * A pin should not be freed more times than allocated.
 221                  */
 222                 if (WARN_ON(!desc->mux_usecount))
 223                         return NULL;
 224                 desc->mux_usecount--;
 225                 if (desc->mux_usecount)
 226                         return NULL;
 227         }
 228
 229         /*
 230          * If there is no kind of request function for the pin we just assume
 231          * we got it by default and proceed.
 232          */
 233         if (gpio_range && ops->gpio_disable_free)
 234                 ops->gpio_disable_free(pctldev, gpio_range, pin);
 235         else if (ops->free)
 236                 ops->free(pctldev, pin);
 237
 238         if (gpio_range) {
 239                 owner = desc->gpio_owner;
 240                 desc->gpio_owner = NULL;
 241         } else {
 242                 owner = desc->mux_owner;
 243                 desc->mux_owner = NULL;
 244                 desc->mux_setting = NULL;
 245         }
 246
 247         module_put(pctldev->owner);
 248
 249         return owner;
 250 }
 251
 252 /**
 253  * pinmux_request_gpio() - request pinmuxing for a GPIO pin
 254  * @pctldev: pin controller device affected
 255  * @pin: the pin to mux in for GPIO
 256  * @range: the applicable GPIO range
 257  */
 258 int pinmux_request_gpio(struct pinctrl_dev *pctldev,
 259                         struct pinctrl_gpio_range *range,
 260                         unsigned pin, unsigned gpio)
 261 {
 262         const char *owner;
 263         int ret;
 264
 265         /* Conjure some name stating what chip and pin this is taken by */
 266         owner = kasprintf(GFP_KERNEL, "%s:%d", range->name, gpio);
 267         if (!owner)
 268                 return -ENOMEM;
 269
 270         ret = pin_request(pctldev, pin, owner, range);
 271         if (ret < 0)
 272                 kfree(owner);
 273
 274         return ret;
 275 }
 276
 277 /**
 278  * pinmux_free_gpio() - release a pin from GPIO muxing
 279  * @pctldev: the pin controller device for the pin
 280  * @pin: the affected currently GPIO-muxed in pin
 281  * @range: applicable GPIO range
 282  */
 283 void pinmux_free_gpio(struct pinctrl_dev *pctldev, unsigned pin,
 284                       struct pinctrl_gpio_range *range)
 285 {
 286         const char *owner;
 287
 288         owner = pin_free(pctldev, pin, range);
 289         kfree(owner);
 290 }
 291
 292 /**
 293  * pinmux_gpio_direction() - set the direction of a single muxed-in GPIO pin
 294  * @pctldev: the pin controller handling this pin
 295  * @range: applicable GPIO range
 296  * @pin: the affected GPIO pin in this controller
 297  * @input: true if we set the pin as input, false for output
 298  */
 299 int pinmux_gpio_direction(struct pinctrl_dev *pctldev,
 300                           struct pinctrl_gpio_range *range,
 301                           unsigned pin, bool input)
 302 {
 303         const struct pinmux_ops *ops;
 304         int ret;
 305
 306         ops = pctldev->desc->pmxops;
 307
 308         if (ops->gpio_set_direction)
 309                 ret = ops->gpio_set_direction(pctldev, range, pin, input);
 310         else
 311                 ret = 0;
 312
 313         return ret;
 314 }
 315
 316 static int pinmux_func_name_to_selector(struct pinctrl_dev *pctldev,
 317                                         const char *function)
 318 {
 319         const struct pinmux_ops *ops = pctldev->desc->pmxops;
 320         unsigned nfuncs = ops->get_functions_count(pctldev);
 321         unsigned selector = 0;
 322
 323         /* See if this pctldev has this function */
 324         while (selector < nfuncs) {
 325                 const char *fname = ops->get_function_name(pctldev, selector);
 326
 327                 if (!strcmp(function, fname))
 328                         return selector;
 329
 330                 selector++;
 331         }
 332
 333         return -EINVAL;
 334 }
 335
 336 int pinmux_map_to_setting(const struct pinctrl_map *map,
 337                           struct pinctrl_setting *setting)
 338 {
 339         struct pinctrl_dev *pctldev = setting->pctldev;
 340         const struct pinmux_ops *pmxops = pctldev->desc->pmxops;
 341         char const * const *groups;
 342         unsigned num_groups;
 343         int ret;
 344         const char *group;
 345
 346         if (!pmxops) {
 347                 dev_err(pctldev->dev, "does not support mux function\n");
 348                 return -EINVAL;
 349         }
 350
 351         ret = pinmux_func_name_to_selector(pctldev, map->data.mux.function);
 352         if (ret < 0) {
 353                 dev_err(pctldev->dev, "invalid function %s in map table\n",
 354                         map->data.mux.function);
 355                 return ret;
 356         }
 357         setting->data.mux.func = ret;
 358
 359         ret = pmxops->get_function_groups(pctldev, setting->data.mux.func,
 360                                           &groups, &num_groups);
 361         if (ret < 0) {
 362                 dev_err(pctldev->dev, "can't query groups for function %s\n",
 363                         map->data.mux.function);
 364                 return ret;
 365         }
 366         if (!num_groups) {
 367                 dev_err(pctldev->dev,
 368                         "function %s can't be selected on any group\n",
 369                         map->data.mux.function);
 370                 return -EINVAL;
 371         }
 372         if (map->data.mux.group) {
 373                 group = map->data.mux.group;
 374                 ret = match_string(groups, num_groups, group);
 375                 if (ret < 0) {
 376                         dev_err(pctldev->dev,
 377                                 "invalid group \"%s\" for function \"%s\"\n",
 378                                 group, map->data.mux.function);
 379                         return ret;
 380                 }
 381         } else {
 382                 group = groups[0];
 383         }
 384
 385         ret = pinctrl_get_group_selector(pctldev, group);
 386         if (ret < 0) {
 387                 dev_err(pctldev->dev, "invalid group %s in map table\n",
 388                         map->data.mux.group);
 389                 return ret;
 390         }
 391         setting->data.mux.group = ret;
 392
 393         return 0;
 394 }
 395
 396 void pinmux_free_setting(const struct pinctrl_setting *setting)
 397 {
 398         /* This function is currently unused */
 399 }
 400
 401 int pinmux_enable_setting(const struct pinctrl_setting *setting)
 402 {
 403         struct pinctrl_dev *pctldev = setting->pctldev;
 404         const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
 405         const struct pinmux_ops *ops = pctldev->desc->pmxops;
 406         int ret = 0;
 407         const unsigned *pins = NULL;
 408         unsigned num_pins = 0;
 409         int i;
 410         struct pin_desc *desc;
 411
 412         if (pctlops->get_group_pins)
 413                 ret = pctlops->get_group_pins(pctldev, setting->data.mux.group,
 414                                               &pins, &num_pins);
 415
 416         if (ret) {
 417                 const char *gname;
 418
 419                 /* errors only affect debug data, so just warn */
 420                 gname = pctlops->get_group_name(pctldev,
 421                                                 setting->data.mux.group);
 422                 dev_warn(pctldev->dev,
 423                          "could not get pins for group %s\n",
 424                          gname);
 425                 num_pins = 0;
 426         }
 427
 428         /* Try to allocate all pins in this group, one by one */
 429         for (i = 0; i < num_pins; i++) {
 430                 ret = pin_request(pctldev, pins[i], setting->dev_name, NULL);
 431                 if (ret) {
 432                         const char *gname;
 433                         const char *pname;
 434
 435                         desc = pin_desc_get(pctldev, pins[i]);
 436                         pname = desc ? desc->name : "non-existing";
 437                         gname = pctlops->get_group_name(pctldev,
 438                                                 setting->data.mux.group);
 439                         dev_err(pctldev->dev,
 440                                 "could not request pin %d (%s) from group %s "
 441                                 " on device %s\n",
 442                                 pins[i], pname, gname,
 443                                 pinctrl_dev_get_name(pctldev));
 444                         goto err_pin_request;
 445                 }
 446         }
 447
 448         /* Now that we have acquired the pins, encode the mux setting */
 449         for (i = 0; i < num_pins; i++) {
 450                 desc = pin_desc_get(pctldev, pins[i]);
 451                 if (desc == NULL) {
 452                         dev_warn(pctldev->dev,
 453                                  "could not get pin desc for pin %d\n",
 454                                  pins[i]);
 455                         continue;
 456                 }
 457                 desc->mux_setting = &(setting->data.mux);
 458         }
 459
 460         ret = ops->set_mux(pctldev, setting->data.mux.func,
 461                            setting->data.mux.group);
 462
 463         if (ret)
 464                 goto err_set_mux;
 465
 466         return 0;
 467
 468 err_set_mux:
 469         for (i = 0; i < num_pins; i++) {
 470                 desc = pin_desc_get(pctldev, pins[i]);
 471                 if (desc)
 472                         desc->mux_setting = NULL;
 473         }
 474 err_pin_request:
 475         /* On error release all taken pins */
 476         while (--i >= 0)
 477                 pin_free(pctldev, pins[i], NULL);
 478
 479         return ret;
 480 }
 481
 482 void pinmux_disable_setting(const struct pinctrl_setting *setting)
 483 {
 484         struct pinctrl_dev *pctldev = setting->pctldev;
 485         const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
 486         int ret = 0;
 487         const unsigned *pins = NULL;
 488         unsigned num_pins = 0;
 489         int i;
 490         struct pin_desc *desc;
 491
 492         if (pctlops->get_group_pins)
 493                 ret = pctlops->get_group_pins(pctldev, setting->data.mux.group,
 494                                               &pins, &num_pins);
 495         if (ret) {
 496                 const char *gname;
 497
 498                 /* errors only affect debug data, so just warn */
 499                 gname = pctlops->get_group_name(pctldev,
 500                                                 setting->data.mux.group);
 501                 dev_warn(pctldev->dev,
 502                          "could not get pins for group %s\n",
 503                          gname);
 504                 num_pins = 0;
 505         }
 506
 507         /* Flag the descs that no setting is active */
 508         for (i = 0; i < num_pins; i++) {
 509                 desc = pin_desc_get(pctldev, pins[i]);
 510                 if (desc == NULL) {
 511                         dev_warn(pctldev->dev,
 512                                  "could not get pin desc for pin %d\n",
 513                                  pins[i]);
 514                         continue;
 515                 }
 516                 if (desc->mux_setting == &(setting->data.mux)) {
 517                         pin_free(pctldev, pins[i], NULL);
 518                 } else {
 519                         const char *gname;
 520
 521                         gname = pctlops->get_group_name(pctldev,
 522                                                 setting->data.mux.group);
 523                         dev_warn(pctldev->dev,
 524                                  "not freeing pin %d (%s) as part of "
 525                                  "deactivating group %s - it is already "
 526                                  "used for some other setting",
 527                                  pins[i], desc->name, gname);
 528                 }
 529         }
 530 }
 531
 532 #ifdef CONFIG_DEBUG_FS
 533
 534 /* Called from pincontrol core */
 535 static int pinmux_functions_show(struct seq_file *s, void *what)
 536 {
 537         struct pinctrl_dev *pctldev = s->private;
 538         const struct pinmux_ops *pmxops = pctldev->desc->pmxops;
 539         unsigned nfuncs;
 540         unsigned func_selector = 0;
 541
 542         if (!pmxops)
 543                 return 0;
 544
 545         mutex_lock(&pctldev->mutex);
 546         nfuncs = pmxops->get_functions_count(pctldev);
 547         while (func_selector < nfuncs) {
 548                 const char *func = pmxops->get_function_name(pctldev,
 549                                                           func_selector);
 550                 const char * const *groups;
 551                 unsigned num_groups;
 552                 int ret;
 553                 int i;
 554
 555                 ret = pmxops->get_function_groups(pctldev, func_selector,
 556                                                   &groups, &num_groups);
 557                 if (ret) {
 558                         seq_printf(s, "function %s: COULD NOT GET GROUPS\n",
 559                                    func);
 560                         func_selector++;
 561                         continue;
 562                 }
 563
 564                 seq_printf(s, "function: %s, groups = [ ", func);
 565                 for (i = 0; i < num_groups; i++)
 566                         seq_printf(s, "%s ", groups[i]);
 567                 seq_puts(s, "]\n");
 568
 569                 func_selector++;
 570         }
 571
 572         mutex_unlock(&pctldev->mutex);
 573
 574         return 0;
 575 }
 576
 577 static int pinmux_pins_show(struct seq_file *s, void *what)
 578 {
 579         struct pinctrl_dev *pctldev = s->private;
 580         const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
 581         const struct pinmux_ops *pmxops = pctldev->desc->pmxops;
 582         unsigned i, pin;
 583
 584         if (!pmxops)
 585                 return 0;
 586
 587         seq_puts(s, "Pinmux settings per pin\n");
 588         if (pmxops->strict)
 589                 seq_puts(s,
 590                  "Format: pin (name): mux_owner|gpio_owner (strict) hog?\n");
 591         else
 592                 seq_puts(s,
 593                 "Format: pin (name): mux_owner gpio_owner hog?\n");
 594
 595         mutex_lock(&pctldev->mutex);
 596
 597         /* The pin number can be retrived from the pin controller descriptor */
 598         for (i = 0; i < pctldev->desc->npins; i++) {
 599                 struct pin_desc *desc;
 600                 bool is_hog = false;
 601
 602                 pin = pctldev->desc->pins[i].number;
 603                 desc = pin_desc_get(pctldev, pin);
 604                 /* Skip if we cannot search the pin */
 605                 if (desc == NULL)
 606                         continue;
 607
 608                 if (desc->mux_owner &&
 609                     !strcmp(desc->mux_owner, pinctrl_dev_get_name(pctldev)))
 610                         is_hog = true;
 611
 612                 if (pmxops->strict) {
 613                         if (desc->mux_owner)
 614                                 seq_printf(s, "pin %d (%s): device %s%s",
 615                                            pin, desc->name, desc->mux_owner,
 616                                            is_hog ? " (HOG)" : "");
 617                         else if (desc->gpio_owner)
 618                                 seq_printf(s, "pin %d (%s): GPIO %s",
 619                                            pin, desc->name, desc->gpio_owner);
 620                         else
 621                                 seq_printf(s, "pin %d (%s): UNCLAIMED",
 622                                            pin, desc->name);
 623                 } else {
 624                         /* For non-strict controllers */
 625                         seq_printf(s, "pin %d (%s): %s %s%s", pin, desc->name,
 626                                    desc->mux_owner ? desc->mux_owner
 627                                    : "(MUX UNCLAIMED)",
 628                                    desc->gpio_owner ? desc->gpio_owner
 629                                    : "(GPIO UNCLAIMED)",
 630                                    is_hog ? " (HOG)" : "");
 631                 }
 632
 633                 /* If mux: print function+group claiming the pin */
 634                 if (desc->mux_setting)
 635                         seq_printf(s, " function %s group %s\n",
 636                                    pmxops->get_function_name(pctldev,
 637                                         desc->mux_setting->func),
 638                                    pctlops->get_group_name(pctldev,
 639                                         desc->mux_setting->group));
 640                 else
 641                         seq_putc(s, '\n');
 642         }
 643
 644         mutex_unlock(&pctldev->mutex);
 645
 646         return 0;
 647 }
 648
 649 void pinmux_show_map(struct seq_file *s, const struct pinctrl_map *map)
 650 {
 651         seq_printf(s, "group %s\nfunction %s\n",
 652                 map->data.mux.group ? map->data.mux.group : "(default)",
 653                 map->data.mux.function);
 654 }
 655
 656 void pinmux_show_setting(struct seq_file *s,
 657                          const struct pinctrl_setting *setting)
 658 {
 659         struct pinctrl_dev *pctldev = setting->pctldev;
 660         const struct pinmux_ops *pmxops = pctldev->desc->pmxops;
 661         const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
 662
 663         seq_printf(s, "group: %s (%u) function: %s (%u)\n",
 664                    pctlops->get_group_name(pctldev, setting->data.mux.group),
 665                    setting->data.mux.group,
 666                    pmxops->get_function_name(pctldev, setting->data.mux.func),
 667                    setting->data.mux.func);
 668 }
 669
 670 DEFINE_SHOW_ATTRIBUTE(pinmux_functions);
 671 DEFINE_SHOW_ATTRIBUTE(pinmux_pins);
 672
 673 void pinmux_init_device_debugfs(struct dentry *devroot,
 674                          struct pinctrl_dev *pctldev)
 675 {
 676         debugfs_create_file("pinmux-functions", S_IFREG | S_IRUGO,
 677                             devroot, pctldev, &pinmux_functions_fops);
 678         debugfs_create_file("pinmux-pins", S_IFREG | S_IRUGO,
 679                             devroot, pctldev, &pinmux_pins_fops);
 680 }
 681
 682 #endif /* CONFIG_DEBUG_FS */
 683
 684 #ifdef CONFIG_GENERIC_PINMUX_FUNCTIONS
 685
 686 /**
 687  * pinmux_generic_get_function_count() - returns number of functions
 688  * @pctldev: pin controller device
 689  */
 690 int pinmux_generic_get_function_count(struct pinctrl_dev *pctldev)
 691 {
 692         return pctldev->num_functions;
 693 }
 694 EXPORT_SYMBOL_GPL(pinmux_generic_get_function_count);
 695
 696 /**
 697  * pinmux_generic_get_function_name() - returns the function name
 698  * @pctldev: pin controller device
 699  * @selector: function number
 700  */
 701 const char *
 702 pinmux_generic_get_function_name(struct pinctrl_dev *pctldev,
 703                                  unsigned int selector)
 704 {
 705         struct function_desc *function;
 706
 707         function = radix_tree_lookup(&pctldev->pin_function_tree,
 708                                      selector);
 709         if (!function)
 710                 return NULL;
 711
 712         return function->name;
 713 }
 714 EXPORT_SYMBOL_GPL(pinmux_generic_get_function_name);
 715
 716 /**
 717  * pinmux_generic_get_function_groups() - gets the function groups
 718  * @pctldev: pin controller device
 719  * @selector: function number
 720  * @groups: array of pin groups
 721  * @num_groups: number of pin groups
 722  */
 723 int pinmux_generic_get_function_groups(struct pinctrl_dev *pctldev,
 724                                        unsigned int selector,
 725                                        const char * const **groups,
 726                                        unsigned * const num_groups)
 727 {
 728         struct function_desc *function;
 729
 730         function = radix_tree_lookup(&pctldev->pin_function_tree,
 731                                      selector);
 732         if (!function) {
 733                 dev_err(pctldev->dev, "%s could not find function%i\n",
 734                         __func__, selector);
 735                 return -EINVAL;
 736         }
 737         *groups = function->group_names;
 738         *num_groups = function->num_group_names;
 739
 740         return 0;
 741 }
 742 EXPORT_SYMBOL_GPL(pinmux_generic_get_function_groups);
 743
 744 /**
 745  * pinmux_generic_get_function() - returns a function based on the number
 746  * @pctldev: pin controller device
 747  * @group_selector: function number
 748  */
 749 struct function_desc *pinmux_generic_get_function(struct pinctrl_dev *pctldev,
 750                                                   unsigned int selector)
 751 {
 752         struct function_desc *function;
 753
 754         function = radix_tree_lookup(&pctldev->pin_function_tree,
 755                                      selector);
 756         if (!function)
 757                 return NULL;
 758
 759         return function;
 760 }
 761 EXPORT_SYMBOL_GPL(pinmux_generic_get_function);
 762
 763 /**
 764  * pinmux_generic_add_function() - adds a function group
 765  * @pctldev: pin controller device
 766  * @name: name of the function
 767  * @groups: array of pin groups
 768  * @num_groups: number of pin groups
 769  * @data: pin controller driver specific data
 770  */
 771 int pinmux_generic_add_function(struct pinctrl_dev *pctldev,
 772                                 const char *name,
 773                                 const char **groups,
 774                                 const unsigned int num_groups,
 775                                 void *data)
 776 {
 777         struct function_desc *function;
 778         int selector;
 779
 780         if (!name)
 781                 return -EINVAL;
 782
 783         selector = pinmux_func_name_to_selector(pctldev, name);
 784         if (selector >= 0)
 785                 return selector;
 786
 787         selector = pctldev->num_functions;
 788
 789         function = devm_kzalloc(pctldev->dev, sizeof(*function), GFP_KERNEL);
 790         if (!function)
 791                 return -ENOMEM;
 792
 793         function->name = name;
 794         function->group_names = groups;
 795         function->num_group_names = num_groups;
 796         function->data = data;
 797
 798         radix_tree_insert(&pctldev->pin_function_tree, selector, function);
 799
 800         pctldev->num_functions++;
 801
 802         return selector;
 803 }
 804 EXPORT_SYMBOL_GPL(pinmux_generic_add_function);
 805
 806 /**
 807  * pinmux_generic_remove_function() - removes a numbered function
 808  * @pctldev: pin controller device
 809  * @selector: function number
 810  *
 811  * Note that the caller must take care of locking.
 812  */
 813 int pinmux_generic_remove_function(struct pinctrl_dev *pctldev,
 814                                    unsigned int selector)
 815 {
 816         struct function_desc *function;
 817
 818         function = radix_tree_lookup(&pctldev->pin_function_tree,
 819                                      selector);
 820         if (!function)
 821                 return -ENOENT;
 822
 823         radix_tree_delete(&pctldev->pin_function_tree, selector);
 824         devm_kfree(pctldev->dev, function);
 825
 826         pctldev->num_functions--;
 827
 828         return 0;
 829 }
 830 EXPORT_SYMBOL_GPL(pinmux_generic_remove_function);
 831
 832 /**
 833  * pinmux_generic_free_functions() - removes all functions
 834  * @pctldev: pin controller device
 835  *
 836  * Note that the caller must take care of locking. The pinctrl
 837  * functions are allocated with devm_kzalloc() so no need to free
 838  * them here.
 839  */
 840 void pinmux_generic_free_functions(struct pinctrl_dev *pctldev)
 841 {
 842         struct radix_tree_iter iter;
 843         void __rcu **slot;
 844
 845         radix_tree_for_each_slot(slot, &pctldev->pin_function_tree, &iter, 0)
 846                 radix_tree_delete(&pctldev->pin_function_tree, iter.index);
 847
 848         pctldev->num_functions = 0;
 849 }
 850
 851 #endif /* CONFIG_GENERIC_PINMUX_FUNCTIONS */