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