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/uaccess.h>
  21 #include <linux/pinctrl/machine.h>
  22 #include <linux/pinctrl/pinctrl.h>
  23 #include <linux/pinctrl/pinconf.h>
  24 #include "core.h"
  25 #include "pinconf.h"
  26
  27 int pinconf_check_ops(struct pinctrl_dev *pctldev)
  28 {
  29         const struct pinconf_ops *ops = pctldev->desc->confops;
  30
  31         /* We must be able to read out pin status */
  32         if (!ops->pin_config_get && !ops->pin_config_group_get) {
  33                 dev_err(pctldev->dev,
  34                         "pinconf must be able to read out pin status\n");
  35                 return -EINVAL;
  36         }
  37         /* We have to be able to config the pins in SOME way */
  38         if (!ops->pin_config_set && !ops->pin_config_group_set) {
  39                 dev_err(pctldev->dev,
  40                         "pinconf has to be able to set a pins config\n");
  41                 return -EINVAL;
  42         }
  43         return 0;
  44 }
  45
  46 int pinconf_validate_map(struct pinctrl_map const *map, int i)
  47 {
  48         if (!map->data.configs.group_or_pin) {
  49                 pr_err("failed to register map %s (%d): no group/pin given\n",
  50                        map->name, i);
  51                 return -EINVAL;
  52         }
  53
  54         if (!map->data.configs.num_configs ||
  55                         !map->data.configs.configs) {
  56                 pr_err("failed to register map %s (%d): no configs given\n",
  57                        map->name, i);
  58                 return -EINVAL;
  59         }
  60
  61         return 0;
  62 }
  63
  64 int pin_config_get_for_pin(struct pinctrl_dev *pctldev, unsigned pin,
  65                            unsigned long *config)
  66 {
  67         const struct pinconf_ops *ops = pctldev->desc->confops;
  68
  69         if (!ops || !ops->pin_config_get) {
  70                 dev_err(pctldev->dev, "cannot get pin configuration, missing "
  71                         "pin_config_get() function in driver\n");
  72                 return -EINVAL;
  73         }
  74
  75         return ops->pin_config_get(pctldev, pin, config);
  76 }
  77
  78 int pin_config_group_get(const char *dev_name, const char *pin_group,
  79                          unsigned long *config)
  80 {
  81         struct pinctrl_dev *pctldev;
  82         const struct pinconf_ops *ops;
  83         int selector, ret;
  84
  85         pctldev = get_pinctrl_dev_from_devname(dev_name);
  86         if (!pctldev) {
  87                 ret = -EINVAL;
  88                 return ret;
  89         }
  90
  91         mutex_lock(&pctldev->mutex);
  92
  93         ops = pctldev->desc->confops;
  94
  95         if (!ops || !ops->pin_config_group_get) {
  96                 dev_err(pctldev->dev, "cannot get configuration for pin "
  97                         "group, missing group config get function in "
  98                         "driver\n");
  99                 ret = -EINVAL;
 100                 goto unlock;
 101         }
 102
 103         selector = pinctrl_get_group_selector(pctldev, pin_group);
 104         if (selector < 0) {
 105                 ret = selector;
 106                 goto unlock;
 107         }
 108
 109         ret = ops->pin_config_group_get(pctldev, selector, config);
 110
 111 unlock:
 112         mutex_unlock(&pctldev->mutex);
 113         return ret;
 114 }
 115
 116 int pinconf_map_to_setting(struct pinctrl_map const *map,
 117                           struct pinctrl_setting *setting)
 118 {
 119         struct pinctrl_dev *pctldev = setting->pctldev;
 120         int pin;
 121
 122         switch (setting->type) {
 123         case PIN_MAP_TYPE_CONFIGS_PIN:
 124                 pin = pin_get_from_name(pctldev,
 125                                         map->data.configs.group_or_pin);
 126                 if (pin < 0) {
 127                         dev_err(pctldev->dev, "could not map pin config for \"%s\"",
 128                                 map->data.configs.group_or_pin);
 129                         return pin;
 130                 }
 131                 setting->data.configs.group_or_pin = pin;
 132                 break;
 133         case PIN_MAP_TYPE_CONFIGS_GROUP:
 134                 pin = pinctrl_get_group_selector(pctldev,
 135                                          map->data.configs.group_or_pin);
 136                 if (pin < 0) {
 137                         dev_err(pctldev->dev, "could not map group config for \"%s\"",
 138                                 map->data.configs.group_or_pin);
 139                         return pin;
 140                 }
 141                 setting->data.configs.group_or_pin = pin;
 142                 break;
 143         default:
 144                 return -EINVAL;
 145         }
 146
 147         setting->data.configs.num_configs = map->data.configs.num_configs;
 148         setting->data.configs.configs = map->data.configs.configs;
 149
 150         return 0;
 151 }
 152
 153 void pinconf_free_setting(struct pinctrl_setting const *setting)
 154 {
 155 }
 156
 157 int pinconf_apply_setting(struct pinctrl_setting const *setting)
 158 {
 159         struct pinctrl_dev *pctldev = setting->pctldev;
 160         const struct pinconf_ops *ops = pctldev->desc->confops;
 161         int i, ret;
 162
 163         if (!ops) {
 164                 dev_err(pctldev->dev, "missing confops\n");
 165                 return -EINVAL;
 166         }
 167
 168         switch (setting->type) {
 169         case PIN_MAP_TYPE_CONFIGS_PIN:
 170                 if (!ops->pin_config_set) {
 171                         dev_err(pctldev->dev, "missing pin_config_set op\n");
 172                         return -EINVAL;
 173                 }
 174                 for (i = 0; i < setting->data.configs.num_configs; i++) {
 175                         ret = ops->pin_config_set(pctldev,
 176                                         setting->data.configs.group_or_pin,
 177                                         setting->data.configs.configs[i]);
 178                         if (ret < 0) {
 179                                 dev_err(pctldev->dev,
 180                                         "pin_config_set op failed for pin %d config %08lx\n",
 181                                         setting->data.configs.group_or_pin,
 182                                         setting->data.configs.configs[i]);
 183                                 return ret;
 184                         }
 185                 }
 186                 break;
 187         case PIN_MAP_TYPE_CONFIGS_GROUP:
 188                 if (!ops->pin_config_group_set) {
 189                         dev_err(pctldev->dev,
 190                                 "missing pin_config_group_set op\n");
 191                         return -EINVAL;
 192                 }
 193                 for (i = 0; i < setting->data.configs.num_configs; i++) {
 194                         ret = ops->pin_config_group_set(pctldev,
 195                                         setting->data.configs.group_or_pin,
 196                                         setting->data.configs.configs[i]);
 197                         if (ret < 0) {
 198                                 dev_err(pctldev->dev,
 199                                         "pin_config_group_set op failed for group %d config %08lx\n",
 200                                         setting->data.configs.group_or_pin,
 201                                         setting->data.configs.configs[i]);
 202                                 return ret;
 203                         }
 204                 }
 205                 break;
 206         default:
 207                 return -EINVAL;
 208         }
 209
 210         return 0;
 211 }
 212
 213 #ifdef CONFIG_DEBUG_FS
 214
 215 void pinconf_show_map(struct seq_file *s, struct pinctrl_map const *map)
 216 {
 217         struct pinctrl_dev *pctldev;
 218         const struct pinconf_ops *confops;
 219         int i;
 220
 221         pctldev = get_pinctrl_dev_from_devname(map->ctrl_dev_name);
 222         if (pctldev)
 223                 confops = pctldev->desc->confops;
 224         else
 225                 confops = NULL;
 226
 227         switch (map->type) {
 228         case PIN_MAP_TYPE_CONFIGS_PIN:
 229                 seq_printf(s, "pin ");
 230                 break;
 231         case PIN_MAP_TYPE_CONFIGS_GROUP:
 232                 seq_printf(s, "group ");
 233                 break;
 234         default:
 235                 break;
 236         }
 237
 238         seq_printf(s, "%s\n", map->data.configs.group_or_pin);
 239
 240         for (i = 0; i < map->data.configs.num_configs; i++) {
 241                 seq_printf(s, "config ");
 242                 if (confops && confops->pin_config_config_dbg_show)
 243                         confops->pin_config_config_dbg_show(pctldev, s,
 244                                                 map->data.configs.configs[i]);
 245                 else
 246                         seq_printf(s, "%08lx", map->data.configs.configs[i]);
 247                 seq_printf(s, "\n");
 248         }
 249 }
 250
 251 void pinconf_show_setting(struct seq_file *s,
 252                           struct pinctrl_setting const *setting)
 253 {
 254         struct pinctrl_dev *pctldev = setting->pctldev;
 255         const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
 256         const struct pinconf_ops *confops = pctldev->desc->confops;
 257         struct pin_desc *desc;
 258         int i;
 259
 260         switch (setting->type) {
 261         case PIN_MAP_TYPE_CONFIGS_PIN:
 262                 desc = pin_desc_get(setting->pctldev,
 263                                     setting->data.configs.group_or_pin);
 264                 seq_printf(s, "pin %s (%d)",
 265                            desc->name ? desc->name : "unnamed",
 266                            setting->data.configs.group_or_pin);
 267                 break;
 268         case PIN_MAP_TYPE_CONFIGS_GROUP:
 269                 seq_printf(s, "group %s (%d)",
 270                            pctlops->get_group_name(pctldev,
 271                                         setting->data.configs.group_or_pin),
 272                            setting->data.configs.group_or_pin);
 273                 break;
 274         default:
 275                 break;
 276         }
 277
 278         /*
 279          * FIXME: We should really get the pin controler to dump the config
 280          * values, so they can be decoded to something meaningful.
 281          */
 282         for (i = 0; i < setting->data.configs.num_configs; i++) {
 283                 seq_printf(s, " ");
 284                 if (confops && confops->pin_config_config_dbg_show)
 285                         confops->pin_config_config_dbg_show(pctldev, s,
 286                                 setting->data.configs.configs[i]);
 287                 else
 288                         seq_printf(s, "%08lx",
 289                                    setting->data.configs.configs[i]);
 290         }
 291
 292         seq_printf(s, "\n");
 293 }
 294
 295 static void pinconf_dump_pin(struct pinctrl_dev *pctldev,
 296                              struct seq_file *s, int pin)
 297 {
 298         const struct pinconf_ops *ops = pctldev->desc->confops;
 299
 300         /* no-op when not using generic pin config */
 301         pinconf_generic_dump_pin(pctldev, s, pin);
 302         if (ops && ops->pin_config_dbg_show)
 303                 ops->pin_config_dbg_show(pctldev, s, pin);
 304 }
 305
 306 static int pinconf_pins_show(struct seq_file *s, void *what)
 307 {
 308         struct pinctrl_dev *pctldev = s->private;
 309         const struct pinconf_ops *ops = pctldev->desc->confops;
 310         unsigned i, pin;
 311
 312         if (!ops || !ops->pin_config_get)
 313                 return 0;
 314
 315         seq_puts(s, "Pin config settings per pin\n");
 316         seq_puts(s, "Format: pin (name): configs\n");
 317
 318         mutex_lock(&pctldev->mutex);
 319
 320         /* The pin number can be retrived from the pin controller descriptor */
 321         for (i = 0; i < pctldev->desc->npins; i++) {
 322                 struct pin_desc *desc;
 323
 324                 pin = pctldev->desc->pins[i].number;
 325                 desc = pin_desc_get(pctldev, pin);
 326                 /* Skip if we cannot search the pin */
 327                 if (desc == NULL)
 328                         continue;
 329
 330                 seq_printf(s, "pin %d (%s):", pin,
 331                            desc->name ? desc->name : "unnamed");
 332
 333                 pinconf_dump_pin(pctldev, s, pin);
 334
 335                 seq_printf(s, "\n");
 336         }
 337
 338         mutex_unlock(&pctldev->mutex);
 339
 340         return 0;
 341 }
 342
 343 static void pinconf_dump_group(struct pinctrl_dev *pctldev,
 344                                struct seq_file *s, unsigned selector,
 345                                const char *gname)
 346 {
 347         const struct pinconf_ops *ops = pctldev->desc->confops;
 348
 349         /* no-op when not using generic pin config */
 350         pinconf_generic_dump_group(pctldev, s, gname);
 351         if (ops && ops->pin_config_group_dbg_show)
 352                 ops->pin_config_group_dbg_show(pctldev, s, selector);
 353 }
 354
 355 static int pinconf_groups_show(struct seq_file *s, void *what)
 356 {
 357         struct pinctrl_dev *pctldev = s->private;
 358         const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
 359         const struct pinconf_ops *ops = pctldev->desc->confops;
 360         unsigned ngroups = pctlops->get_groups_count(pctldev);
 361         unsigned selector = 0;
 362
 363         if (!ops || !ops->pin_config_group_get)
 364                 return 0;
 365
 366         seq_puts(s, "Pin config settings per pin group\n");
 367         seq_puts(s, "Format: group (name): configs\n");
 368
 369         while (selector < ngroups) {
 370                 const char *gname = pctlops->get_group_name(pctldev, selector);
 371
 372                 seq_printf(s, "%u (%s):", selector, gname);
 373                 pinconf_dump_group(pctldev, s, selector, gname);
 374                 seq_printf(s, "\n");
 375
 376                 selector++;
 377         }
 378
 379         return 0;
 380 }
 381
 382 static int pinconf_pins_open(struct inode *inode, struct file *file)
 383 {
 384         return single_open(file, pinconf_pins_show, inode->i_private);
 385 }
 386
 387 static int pinconf_groups_open(struct inode *inode, struct file *file)
 388 {
 389         return single_open(file, pinconf_groups_show, inode->i_private);
 390 }
 391
 392 static const struct file_operations pinconf_pins_ops = {
 393         .open           = pinconf_pins_open,
 394         .read           = seq_read,
 395         .llseek         = seq_lseek,
 396         .release        = single_release,
 397 };
 398
 399 static const struct file_operations pinconf_groups_ops = {
 400         .open           = pinconf_groups_open,
 401         .read           = seq_read,
 402         .llseek         = seq_lseek,
 403         .release        = single_release,
 404 };
 405
 406 #define MAX_NAME_LEN 15
 407
 408 struct dbg_cfg {
 409         enum pinctrl_map_type map_type;
 410         char dev_name[MAX_NAME_LEN+1];
 411         char state_name[MAX_NAME_LEN+1];
 412         char pin_name[MAX_NAME_LEN+1];
 413 };
 414
 415 /*
 416  * Goal is to keep this structure as global in order to simply read the
 417  * pinconf-config file after a write to check config is as expected
 418  */
 419 static struct dbg_cfg pinconf_dbg_conf;
 420
 421 /**
 422  * pinconf_dbg_config_print() - display the pinctrl config from the pinctrl
 423  * map, of the dev/pin/state that was last written to pinconf-config file.
 424  * @s: string filled in  with config description
 425  * @d: not used
 426  */
 427 static int pinconf_dbg_config_print(struct seq_file *s, void *d)
 428 {
 429         struct pinctrl_maps *maps_node;
 430         const struct pinctrl_map *map;
 431         struct pinctrl_dev *pctldev = NULL;
 432         const struct pinconf_ops *confops = NULL;
 433         const struct pinctrl_map_configs *configs;
 434         struct dbg_cfg *dbg = &pinconf_dbg_conf;
 435         int i, j;
 436         bool found = false;
 437         unsigned long config;
 438
 439         mutex_lock(&pinctrl_maps_mutex);
 440
 441         /* Parse the pinctrl map and look for the elected pin/state */
 442         for_each_maps(maps_node, i, map) {
 443                 if (map->type != dbg->map_type)
 444                         continue;
 445                 if (strcmp(map->dev_name, dbg->dev_name))
 446                         continue;
 447                 if (strcmp(map->name, dbg->state_name))
 448                         continue;
 449
 450                 for (j = 0; j < map->data.configs.num_configs; j++) {
 451                         if (!strcmp(map->data.configs.group_or_pin,
 452                                         dbg->pin_name)) {
 453                                 /*
 454                                  * We found the right pin / state, read the
 455                                  * config and he pctldev for later use
 456                                  */
 457                                 configs = &map->data.configs;
 458                                 pctldev = get_pinctrl_dev_from_devname
 459                                         (map->ctrl_dev_name);
 460                                 found = true;
 461                                 break;
 462                         }
 463                 }
 464         }
 465
 466         if (!found) {
 467                 seq_printf(s, "No config found for dev/state/pin, expected:\n");
 468                 seq_printf(s, "Searched dev:%s\n", dbg->dev_name);
 469                 seq_printf(s, "Searched state:%s\n", dbg->state_name);
 470                 seq_printf(s, "Searched pin:%s\n", dbg->pin_name);
 471                 seq_printf(s, "Use: modify config_pin <devname> "\
 472                                 "<state> <pinname> <value>\n");
 473                 goto exit;
 474         }
 475
 476         config = *(configs->configs);
 477         seq_printf(s, "Dev %s has config of %s in state %s: 0x%08lX\n",
 478                         dbg->dev_name, dbg->pin_name,
 479                         dbg->state_name, config);
 480
 481         if (pctldev)
 482                 confops = pctldev->desc->confops;
 483
 484         if (confops && confops->pin_config_config_dbg_show)
 485                 confops->pin_config_config_dbg_show(pctldev, s, config);
 486
 487 exit:
 488         mutex_unlock(&pinctrl_maps_mutex);
 489
 490         return 0;
 491 }
 492
 493 /**
 494  * pinconf_dbg_config_write() - modify the pinctrl config in the pinctrl
 495  * map, of a dev/pin/state entry based on user entries to pinconf-config
 496  * @user_buf: contains the modification request with expected format:
 497  *     modify config_pin <devicename> <state> <pinname> <newvalue>
 498  * modify is literal string, alternatives like add/delete not supported yet
 499  * config_pin is literal, alternatives like config_mux not supported yet
 500  * <devicename> <state> <pinname> are values that should match the pinctrl-maps
 501  * <newvalue> reflects the new config and is driver dependant
 502  */
 503 static int pinconf_dbg_config_write(struct file *file,
 504         const char __user *user_buf, size_t count, loff_t *ppos)
 505 {
 506         struct pinctrl_maps *maps_node;
 507         const struct pinctrl_map *map;
 508         struct pinctrl_dev *pctldev = NULL;
 509         const struct pinconf_ops *confops = NULL;
 510         struct dbg_cfg *dbg = &pinconf_dbg_conf;
 511         const struct pinctrl_map_configs *configs;
 512         char config[MAX_NAME_LEN+1];
 513         bool found = false;
 514         char buf[128];
 515         char *b = &buf[0];
 516         int buf_size;
 517         char *token;
 518         int i;
 519
 520         /* Get userspace string and assure termination */
 521         buf_size = min(count, (sizeof(buf)-1));
 522         if (copy_from_user(buf, user_buf, buf_size))
 523                 return -EFAULT;
 524         buf[buf_size] = 0;
 525
 526         /*
 527          * need to parse entry and extract parameters:
 528          * modify configs_pin devicename state pinname newvalue
 529          */
 530
 531         /* Get arg: 'modify' */
 532         token = strsep(&b, " ");
 533         if (!token)
 534                 return -EINVAL;
 535         if (strcmp(token, "modify"))
 536                 return -EINVAL;
 537
 538         /* Get arg type: "config_pin" type supported so far */
 539         token = strsep(&b, " ");
 540         if (!token)
 541                 return -EINVAL;
 542         if (strcmp(token, "config_pin"))
 543                 return -EINVAL;
 544         dbg->map_type = PIN_MAP_TYPE_CONFIGS_PIN;
 545
 546         /* get arg 'device_name' */
 547         token = strsep(&b, " ");
 548         if (token == NULL)
 549                 return -EINVAL;
 550         if (strlen(token) >= MAX_NAME_LEN)
 551                 return -EINVAL;
 552         strncpy(dbg->dev_name, token, MAX_NAME_LEN);
 553
 554         /* get arg 'state_name' */
 555         token = strsep(&b, " ");
 556         if (token == NULL)
 557                 return -EINVAL;
 558         if (strlen(token) >= MAX_NAME_LEN)
 559                 return -EINVAL;
 560         strncpy(dbg->state_name, token, MAX_NAME_LEN);
 561
 562         /* get arg 'pin_name' */
 563         token = strsep(&b, " ");
 564         if (token == NULL)
 565                 return -EINVAL;
 566         if (strlen(token) >= MAX_NAME_LEN)
 567                 return -EINVAL;
 568         strncpy(dbg->pin_name, token, MAX_NAME_LEN);
 569
 570         /* get new_value of config' */
 571         token = strsep(&b, " ");
 572         if (token == NULL)
 573                 return -EINVAL;
 574         if (strlen(token) >= MAX_NAME_LEN)
 575                 return -EINVAL;
 576         strncpy(config, token, MAX_NAME_LEN);
 577
 578         mutex_lock(&pinctrl_maps_mutex);
 579
 580         /* Parse the pinctrl map and look for the selected dev/state/pin */
 581         for_each_maps(maps_node, i, map) {
 582                 if (strcmp(map->dev_name, dbg->dev_name))
 583                         continue;
 584                 if (map->type != dbg->map_type)
 585                         continue;
 586                 if (strcmp(map->name, dbg->state_name))
 587                         continue;
 588
 589                 /*  we found the right pin / state, so overwrite config */
 590                 if (!strcmp(map->data.configs.group_or_pin, dbg->pin_name)) {
 591                         found = true;
 592                         pctldev = get_pinctrl_dev_from_devname(
 593                                         map->ctrl_dev_name);
 594                         configs = &map->data.configs;
 595                         break;
 596                 }
 597         }
 598
 599         if (!found) {
 600                 count = -EINVAL;
 601                 goto exit;
 602         }
 603
 604         if (pctldev)
 605                 confops = pctldev->desc->confops;
 606
 607         if (confops && confops->pin_config_dbg_parse_modify) {
 608                 for (i = 0; i < configs->num_configs; i++) {
 609                         confops->pin_config_dbg_parse_modify(pctldev,
 610                                                      config,
 611                                                      &configs->configs[i]);
 612                 }
 613         }
 614
 615 exit:
 616         mutex_unlock(&pinctrl_maps_mutex);
 617
 618         return count;
 619 }
 620
 621 static int pinconf_dbg_config_open(struct inode *inode, struct file *file)
 622 {
 623         return single_open(file, pinconf_dbg_config_print, inode->i_private);
 624 }
 625
 626 static const struct file_operations pinconf_dbg_pinconfig_fops = {
 627         .open = pinconf_dbg_config_open,
 628         .write = pinconf_dbg_config_write,
 629         .read = seq_read,
 630         .llseek = seq_lseek,
 631         .release = single_release,
 632         .owner = THIS_MODULE,
 633 };
 634
 635 void pinconf_init_device_debugfs(struct dentry *devroot,
 636                          struct pinctrl_dev *pctldev)
 637 {
 638         debugfs_create_file("pinconf-pins", S_IFREG | S_IRUGO,
 639                             devroot, pctldev, &pinconf_pins_ops);
 640         debugfs_create_file("pinconf-groups", S_IFREG | S_IRUGO,
 641                             devroot, pctldev, &pinconf_groups_ops);
 642         debugfs_create_file("pinconf-config",  (S_IRUGO | S_IWUSR | S_IWGRP),
 643                             devroot, pctldev, &pinconf_dbg_pinconfig_fops);
 644 }
 645
 646 #endif