drivers/pinctrl/pinmux.c

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