drivers/pinctrl/pinconf.c

   1 /*
   2  * Core driver for the pin config portions of the pin control subsystem
   3  *
   4  * Copyright (C) 2011 ST-Ericsson SA
   5  * Written on behalf of Linaro for ST-Ericsson
   6  *
   7  * Author: Linus Walleij <linus.walleij@linaro.org>
   8  *
   9  * License terms: GNU General Public License (GPL) version 2
  10  */
  11 #define pr_fmt(fmt) "pinconfig core: " fmt
  12
  13 #include <linux/kernel.h>
  14 #include <linux/module.h>
  15 #include <linux/init.h>
  16 #include <linux/device.h>
  17 #include <linux/slab.h>
  18 #include <linux/debugfs.h>
  19 #include <linux/seq_file.h>
  20 #include <linux/pinctrl/machine.h>
  21 #include <linux/pinctrl/pinctrl.h>
  22 #include <linux/pinctrl/pinconf.h>
  23 #include "core.h"
  24 #include "pinconf.h"
  25
  26 int pinconf_check_ops(struct pinctrl_dev *pctldev)
  27 {
  28         const struct pinconf_ops *ops = pctldev->desc->confops;
  29
  30         /* We must be able to read out pin status */
  31         if (!ops->pin_config_get && !ops->pin_config_group_get) {
  32                 dev_err(pctldev->dev,
  33                         "pinconf must be able to read out pin status\n");
  34                 return -EINVAL;
  35         }
  36         /* We have to be able to config the pins in SOME way */
  37         if (!ops->pin_config_set && !ops->pin_config_group_set) {
  38                 dev_err(pctldev->dev,
  39                         "pinconf has to be able to set a pins config\n");
  40                 return -EINVAL;
  41         }
  42         return 0;
  43 }
  44
  45 int pinconf_validate_map(struct pinctrl_map const *map, int i)
  46 {
  47         if (!map->data.configs.group_or_pin) {
  48                 pr_err("failed to register map %s (%d): no group/pin given\n",
  49                        map->name, i);
  50                 return -EINVAL;
  51         }
  52
  53         if (!map->data.configs.num_configs ||
  54                         !map->data.configs.configs) {
  55                 pr_err("failed to register map %s (%d): no configs given\n",
  56                        map->name, i);
  57                 return -EINVAL;
  58         }
  59
  60         return 0;
  61 }
  62
  63 int pin_config_get_for_pin(struct pinctrl_dev *pctldev, unsigned pin,
  64                            unsigned long *config)
  65 {
  66         const struct pinconf_ops *ops = pctldev->desc->confops;
  67
  68         if (!ops || !ops->pin_config_get) {
  69                 dev_err(pctldev->dev, "cannot get pin configuration, missing "
  70                         "pin_config_get() function in driver\n");
  71                 return -EINVAL;
  72         }
  73
  74         return ops->pin_config_get(pctldev, pin, config);
  75 }
  76
  77 /**
  78  * pin_config_get() - get the configuration of a single pin parameter
  79  * @dev_name: name of the pin controller device for this pin
  80  * @name: name of the pin to get the config for
  81  * @config: the config pointed to by this argument will be filled in with the
  82  *      current pin state, it can be used directly by drivers as a numeral, or
  83  *      it can be dereferenced to any struct.
  84  */
  85 int pin_config_get(const char *dev_name, const char *name,
  86                           unsigned long *config)
  87 {
  88         struct pinctrl_dev *pctldev;
  89         int pin;
  90
  91         mutex_lock(&pinctrl_mutex);
  92
  93         pctldev = get_pinctrl_dev_from_devname(dev_name);
  94         if (!pctldev) {
  95                 pin = -EINVAL;
  96                 goto unlock;
  97         }
  98
  99         pin = pin_get_from_name(pctldev, name);
 100         if (pin < 0)
 101                 goto unlock;
 102
 103         pin = pin_config_get_for_pin(pctldev, pin, config);
 104
 105 unlock:
 106         mutex_unlock(&pinctrl_mutex);
 107         return pin;
 108 }
 109 EXPORT_SYMBOL(pin_config_get);
 110
 111 static int pin_config_set_for_pin(struct pinctrl_dev *pctldev, unsigned pin,
 112                            unsigned long config)
 113 {
 114         const struct pinconf_ops *ops = pctldev->desc->confops;
 115         int ret;
 116
 117         if (!ops || !ops->pin_config_set) {
 118                 dev_err(pctldev->dev, "cannot configure pin, missing "
 119                         "config function in driver\n");
 120                 return -EINVAL;
 121         }
 122
 123         ret = ops->pin_config_set(pctldev, pin, config);
 124         if (ret) {
 125                 dev_err(pctldev->dev,
 126                         "unable to set pin configuration on pin %d\n", pin);
 127                 return ret;
 128         }
 129
 130         return 0;
 131 }
 132
 133 /**
 134  * pin_config_set() - set the configuration of a single pin parameter
 135  * @dev_name: name of pin controller device for this pin
 136  * @name: name of the pin to set the config for
 137  * @config: the config in this argument will contain the desired pin state, it
 138  *      can be used directly by drivers as a numeral, or it can be dereferenced
 139  *      to any struct.
 140  */
 141 int pin_config_set(const char *dev_name, const char *name,
 142                    unsigned long config)
 143 {
 144         struct pinctrl_dev *pctldev;
 145         int pin, ret;
 146
 147         mutex_lock(&pinctrl_mutex);
 148
 149         pctldev = get_pinctrl_dev_from_devname(dev_name);
 150         if (!pctldev) {
 151                 ret = -EINVAL;
 152                 goto unlock;
 153         }
 154
 155         pin = pin_get_from_name(pctldev, name);
 156         if (pin < 0) {
 157                 ret = pin;
 158                 goto unlock;
 159         }
 160
 161         ret = pin_config_set_for_pin(pctldev, pin, config);
 162
 163 unlock:
 164         mutex_unlock(&pinctrl_mutex);
 165         return ret;
 166 }
 167 EXPORT_SYMBOL(pin_config_set);
 168
 169 int pin_config_group_get(const char *dev_name, const char *pin_group,
 170                          unsigned long *config)
 171 {
 172         struct pinctrl_dev *pctldev;
 173         const struct pinconf_ops *ops;
 174         int selector, ret;
 175
 176         mutex_lock(&pinctrl_mutex);
 177
 178         pctldev = get_pinctrl_dev_from_devname(dev_name);
 179         if (!pctldev) {
 180                 ret = -EINVAL;
 181                 goto unlock;
 182         }
 183         ops = pctldev->desc->confops;
 184
 185         if (!ops || !ops->pin_config_group_get) {
 186                 dev_err(pctldev->dev, "cannot get configuration for pin "
 187                         "group, missing group config get function in "
 188                         "driver\n");
 189                 ret = -EINVAL;
 190                 goto unlock;
 191         }
 192
 193         selector = pinctrl_get_group_selector(pctldev, pin_group);
 194         if (selector < 0) {
 195                 ret = selector;
 196                 goto unlock;
 197         }
 198
 199         ret = ops->pin_config_group_get(pctldev, selector, config);
 200
 201 unlock:
 202         mutex_unlock(&pinctrl_mutex);
 203         return ret;
 204 }
 205 EXPORT_SYMBOL(pin_config_group_get);
 206
 207 int pin_config_group_set(const char *dev_name, const char *pin_group,
 208                          unsigned long config)
 209 {
 210         struct pinctrl_dev *pctldev;
 211         const struct pinconf_ops *ops;
 212         const struct pinctrl_ops *pctlops;
 213         int selector;
 214         const unsigned *pins;
 215         unsigned num_pins;
 216         int ret;
 217         int i;
 218
 219         mutex_lock(&pinctrl_mutex);
 220
 221         pctldev = get_pinctrl_dev_from_devname(dev_name);
 222         if (!pctldev) {
 223                 ret = -EINVAL;
 224                 goto unlock;
 225         }
 226         ops = pctldev->desc->confops;
 227         pctlops = pctldev->desc->pctlops;
 228
 229         if (!ops || (!ops->pin_config_group_set && !ops->pin_config_set)) {
 230                 dev_err(pctldev->dev, "cannot configure pin group, missing "
 231                         "config function in driver\n");
 232                 ret = -EINVAL;
 233                 goto unlock;
 234         }
 235
 236         selector = pinctrl_get_group_selector(pctldev, pin_group);
 237         if (selector < 0) {
 238                 ret = selector;
 239                 goto unlock;
 240         }
 241
 242         ret = pctlops->get_group_pins(pctldev, selector, &pins, &num_pins);
 243         if (ret) {
 244                 dev_err(pctldev->dev, "cannot configure pin group, error "
 245                         "getting pins\n");
 246                 goto unlock;
 247         }
 248
 249         /*
 250          * If the pin controller supports handling entire groups we use that
 251          * capability.
 252          */
 253         if (ops->pin_config_group_set) {
 254                 ret = ops->pin_config_group_set(pctldev, selector, config);
 255                 /*
 256                  * If the pin controller prefer that a certain group be handled
 257                  * pin-by-pin as well, it returns -EAGAIN.
 258                  */
 259                 if (ret != -EAGAIN)
 260                         goto unlock;
 261         }
 262
 263         /*
 264          * If the controller cannot handle entire groups, we configure each pin
 265          * individually.
 266          */
 267         if (!ops->pin_config_set) {
 268                 ret = 0;
 269                 goto unlock;
 270         }
 271
 272         for (i = 0; i < num_pins; i++) {
 273                 ret = ops->pin_config_set(pctldev, pins[i], config);
 274                 if (ret < 0)
 275                         goto unlock;
 276         }
 277
 278         ret = 0;
 279
 280 unlock:
 281         mutex_unlock(&pinctrl_mutex);
 282
 283         return ret;
 284 }
 285 EXPORT_SYMBOL(pin_config_group_set);
 286
 287 int pinconf_map_to_setting(struct pinctrl_map const *map,
 288                           struct pinctrl_setting *setting)
 289 {
 290         struct pinctrl_dev *pctldev = setting->pctldev;
 291         int pin;
 292
 293         switch (setting->type) {
 294         case PIN_MAP_TYPE_CONFIGS_PIN:
 295                 pin = pin_get_from_name(pctldev,
 296                                         map->data.configs.group_or_pin);
 297                 if (pin < 0) {
 298                         dev_err(pctldev->dev, "could not map pin config for \"%s\"",
 299                                 map->data.configs.group_or_pin);
 300                         return pin;
 301                 }
 302                 setting->data.configs.group_or_pin = pin;
 303                 break;
 304         case PIN_MAP_TYPE_CONFIGS_GROUP:
 305                 pin = pinctrl_get_group_selector(pctldev,
 306                                          map->data.configs.group_or_pin);
 307                 if (pin < 0) {
 308                         dev_err(pctldev->dev, "could not map group config for \"%s\"",
 309                                 map->data.configs.group_or_pin);
 310                         return pin;
 311                 }
 312                 setting->data.configs.group_or_pin = pin;
 313                 break;
 314         default:
 315                 return -EINVAL;
 316         }
 317
 318         setting->data.configs.num_configs = map->data.configs.num_configs;
 319         setting->data.configs.configs = map->data.configs.configs;
 320
 321         return 0;
 322 }
 323
 324 void pinconf_free_setting(struct pinctrl_setting const *setting)
 325 {
 326 }
 327
 328 int pinconf_apply_setting(struct pinctrl_setting const *setting)
 329 {
 330         struct pinctrl_dev *pctldev = setting->pctldev;
 331         const struct pinconf_ops *ops = pctldev->desc->confops;
 332         int i, ret;
 333
 334         if (!ops) {
 335                 dev_err(pctldev->dev, "missing confops\n");
 336                 return -EINVAL;
 337         }
 338
 339         switch (setting->type) {
 340         case PIN_MAP_TYPE_CONFIGS_PIN:
 341                 if (!ops->pin_config_set) {
 342                         dev_err(pctldev->dev, "missing pin_config_set op\n");
 343                         return -EINVAL;
 344                 }
 345                 for (i = 0; i < setting->data.configs.num_configs; i++) {
 346                         ret = ops->pin_config_set(pctldev,
 347                                         setting->data.configs.group_or_pin,
 348                                         setting->data.configs.configs[i]);
 349                         if (ret < 0) {
 350                                 dev_err(pctldev->dev,
 351                                         "pin_config_set op failed for pin %d config %08lx\n",
 352                                         setting->data.configs.group_or_pin,
 353                                         setting->data.configs.configs[i]);
 354                                 return ret;
 355                         }
 356                 }
 357                 break;
 358         case PIN_MAP_TYPE_CONFIGS_GROUP:
 359                 if (!ops->pin_config_group_set) {
 360                         dev_err(pctldev->dev,
 361                                 "missing pin_config_group_set op\n");
 362                         return -EINVAL;
 363                 }
 364                 for (i = 0; i < setting->data.configs.num_configs; i++) {
 365                         ret = ops->pin_config_group_set(pctldev,
 366                                         setting->data.configs.group_or_pin,
 367                                         setting->data.configs.configs[i]);
 368                         if (ret < 0) {
 369                                 dev_err(pctldev->dev,
 370                                         "pin_config_group_set op failed for group %d config %08lx\n",
 371                                         setting->data.configs.group_or_pin,
 372                                         setting->data.configs.configs[i]);
 373                                 return ret;
 374                         }
 375                 }
 376                 break;
 377         default:
 378                 return -EINVAL;
 379         }
 380
 381         return 0;
 382 }
 383
 384 #ifdef CONFIG_DEBUG_FS
 385
 386 void pinconf_show_map(struct seq_file *s, struct pinctrl_map const *map)
 387 {
 388         struct pinctrl_dev *pctldev;
 389         const struct pinconf_ops *confops;
 390         int i;
 391
 392         pctldev = get_pinctrl_dev_from_devname(map->ctrl_dev_name);
 393         if (pctldev)
 394                 confops = pctldev->desc->confops;
 395         else
 396                 confops = NULL;
 397
 398         switch (map->type) {
 399         case PIN_MAP_TYPE_CONFIGS_PIN:
 400                 seq_printf(s, "pin ");
 401                 break;
 402         case PIN_MAP_TYPE_CONFIGS_GROUP:
 403                 seq_printf(s, "group ");
 404                 break;
 405         default:
 406                 break;
 407         }
 408
 409         seq_printf(s, "%s\n", map->data.configs.group_or_pin);
 410
 411         for (i = 0; i < map->data.configs.num_configs; i++) {
 412                 seq_printf(s, "config ");
 413                 if (confops && confops->pin_config_config_dbg_show)
 414                         confops->pin_config_config_dbg_show(pctldev, s,
 415                                                 map->data.configs.configs[i]);
 416                 else
 417                         seq_printf(s, "%08lx", map->data.configs.configs[i]);
 418                 seq_printf(s, "\n");
 419         }
 420 }
 421
 422 void pinconf_show_setting(struct seq_file *s,
 423                           struct pinctrl_setting const *setting)
 424 {
 425         struct pinctrl_dev *pctldev = setting->pctldev;
 426         const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
 427         const struct pinconf_ops *confops = pctldev->desc->confops;
 428         struct pin_desc *desc;
 429         int i;
 430
 431         switch (setting->type) {
 432         case PIN_MAP_TYPE_CONFIGS_PIN:
 433                 desc = pin_desc_get(setting->pctldev,
 434                                     setting->data.configs.group_or_pin);
 435                 seq_printf(s, "pin %s (%d)",
 436                            desc->name ? desc->name : "unnamed",
 437                            setting->data.configs.group_or_pin);
 438                 break;
 439         case PIN_MAP_TYPE_CONFIGS_GROUP:
 440                 seq_printf(s, "group %s (%d)",
 441                            pctlops->get_group_name(pctldev,
 442                                         setting->data.configs.group_or_pin),
 443                            setting->data.configs.group_or_pin);
 444                 break;
 445         default:
 446                 break;
 447         }
 448
 449         /*
 450          * FIXME: We should really get the pin controler to dump the config
 451          * values, so they can be decoded to something meaningful.
 452          */
 453         for (i = 0; i < setting->data.configs.num_configs; i++) {
 454                 seq_printf(s, " ");
 455                 if (confops && confops->pin_config_config_dbg_show)
 456                         confops->pin_config_config_dbg_show(pctldev, s,
 457                                 setting->data.configs.configs[i]);
 458                 else
 459                         seq_printf(s, "%08lx",
 460                                    setting->data.configs.configs[i]);
 461         }
 462
 463         seq_printf(s, "\n");
 464 }
 465
 466 static void pinconf_dump_pin(struct pinctrl_dev *pctldev,
 467                              struct seq_file *s, int pin)
 468 {
 469         const struct pinconf_ops *ops = pctldev->desc->confops;
 470
 471         /* no-op when not using generic pin config */
 472         pinconf_generic_dump_pin(pctldev, s, pin);
 473         if (ops && ops->pin_config_dbg_show)
 474                 ops->pin_config_dbg_show(pctldev, s, pin);
 475 }
 476
 477 static int pinconf_pins_show(struct seq_file *s, void *what)
 478 {
 479         struct pinctrl_dev *pctldev = s->private;
 480         const struct pinconf_ops *ops = pctldev->desc->confops;
 481         unsigned i, pin;
 482
 483         if (!ops || !ops->pin_config_get)
 484                 return 0;
 485
 486         seq_puts(s, "Pin config settings per pin\n");
 487         seq_puts(s, "Format: pin (name): configs\n");
 488
 489         mutex_lock(&pinctrl_mutex);
 490
 491         /* The pin number can be retrived from the pin controller descriptor */
 492         for (i = 0; i < pctldev->desc->npins; i++) {
 493                 struct pin_desc *desc;
 494
 495                 pin = pctldev->desc->pins[i].number;
 496                 desc = pin_desc_get(pctldev, pin);
 497                 /* Skip if we cannot search the pin */
 498                 if (desc == NULL)
 499                         continue;
 500
 501                 seq_printf(s, "pin %d (%s):", pin,
 502                            desc->name ? desc->name : "unnamed");
 503
 504                 pinconf_dump_pin(pctldev, s, pin);
 505
 506                 seq_printf(s, "\n");
 507         }
 508
 509         mutex_unlock(&pinctrl_mutex);
 510
 511         return 0;
 512 }
 513
 514 static void pinconf_dump_group(struct pinctrl_dev *pctldev,
 515                                struct seq_file *s, unsigned selector,
 516                                const char *gname)
 517 {
 518         const struct pinconf_ops *ops = pctldev->desc->confops;
 519
 520         /* no-op when not using generic pin config */
 521         pinconf_generic_dump_group(pctldev, s, gname);
 522         if (ops && ops->pin_config_group_dbg_show)
 523                 ops->pin_config_group_dbg_show(pctldev, s, selector);
 524 }
 525
 526 static int pinconf_groups_show(struct seq_file *s, void *what)
 527 {
 528         struct pinctrl_dev *pctldev = s->private;
 529         const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
 530         const struct pinconf_ops *ops = pctldev->desc->confops;
 531         unsigned ngroups = pctlops->get_groups_count(pctldev);
 532         unsigned selector = 0;
 533
 534         if (!ops || !ops->pin_config_group_get)
 535                 return 0;
 536
 537         seq_puts(s, "Pin config settings per pin group\n");
 538         seq_puts(s, "Format: group (name): configs\n");
 539
 540         while (selector < ngroups) {
 541                 const char *gname = pctlops->get_group_name(pctldev, selector);
 542
 543                 seq_printf(s, "%u (%s):", selector, gname);
 544                 pinconf_dump_group(pctldev, s, selector, gname);
 545                 seq_printf(s, "\n");
 546
 547                 selector++;
 548         }
 549
 550         return 0;
 551 }
 552
 553 static int pinconf_pins_open(struct inode *inode, struct file *file)
 554 {
 555         return single_open(file, pinconf_pins_show, inode->i_private);
 556 }
 557
 558 static int pinconf_groups_open(struct inode *inode, struct file *file)
 559 {
 560         return single_open(file, pinconf_groups_show, inode->i_private);
 561 }
 562
 563 static const struct file_operations pinconf_pins_ops = {
 564         .open           = pinconf_pins_open,
 565         .read           = seq_read,
 566         .llseek         = seq_lseek,
 567         .release        = single_release,
 568 };
 569
 570 static const struct file_operations pinconf_groups_ops = {
 571         .open           = pinconf_groups_open,
 572         .read           = seq_read,
 573         .llseek         = seq_lseek,
 574         .release        = single_release,
 575 };
 576
 577 void pinconf_init_device_debugfs(struct dentry *devroot,
 578                          struct pinctrl_dev *pctldev)
 579 {
 580         debugfs_create_file("pinconf-pins", S_IFREG | S_IRUGO,
 581                             devroot, pctldev, &pinconf_pins_ops);
 582         debugfs_create_file("pinconf-groups", S_IFREG | S_IRUGO,
 583                             devroot, pctldev, &pinconf_groups_ops);
 584 }
 585
 586 #endif