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, "cannot get pin configuration, missing "
  65                         "pin_config_get() function 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 #ifdef CONFIG_DEBUG_FS
 204
 205 void pinconf_show_map(struct seq_file *s, struct pinctrl_map const *map)
 206 {
 207         struct pinctrl_dev *pctldev;
 208         const struct pinconf_ops *confops;
 209         int i;
 210
 211         pctldev = get_pinctrl_dev_from_devname(map->ctrl_dev_name);
 212         if (pctldev)
 213                 confops = pctldev->desc->confops;
 214         else
 215                 confops = NULL;
 216
 217         switch (map->type) {
 218         case PIN_MAP_TYPE_CONFIGS_PIN:
 219                 seq_printf(s, "pin ");
 220                 break;
 221         case PIN_MAP_TYPE_CONFIGS_GROUP:
 222                 seq_printf(s, "group ");
 223                 break;
 224         default:
 225                 break;
 226         }
 227
 228         seq_printf(s, "%s\n", map->data.configs.group_or_pin);
 229
 230         for (i = 0; i < map->data.configs.num_configs; i++) {
 231                 seq_printf(s, "config ");
 232                 if (confops && confops->pin_config_config_dbg_show)
 233                         confops->pin_config_config_dbg_show(pctldev, s,
 234                                                 map->data.configs.configs[i]);
 235                 else
 236                         seq_printf(s, "%08lx", map->data.configs.configs[i]);
 237                 seq_printf(s, "\n");
 238         }
 239 }
 240
 241 void pinconf_show_setting(struct seq_file *s,
 242                           struct pinctrl_setting const *setting)
 243 {
 244         struct pinctrl_dev *pctldev = setting->pctldev;
 245         const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
 246         const struct pinconf_ops *confops = pctldev->desc->confops;
 247         struct pin_desc *desc;
 248         int i;
 249
 250         switch (setting->type) {
 251         case PIN_MAP_TYPE_CONFIGS_PIN:
 252                 desc = pin_desc_get(setting->pctldev,
 253                                     setting->data.configs.group_or_pin);
 254                 seq_printf(s, "pin %s (%d)",
 255                            desc->name ? desc->name : "unnamed",
 256                            setting->data.configs.group_or_pin);
 257                 break;
 258         case PIN_MAP_TYPE_CONFIGS_GROUP:
 259                 seq_printf(s, "group %s (%d)",
 260                            pctlops->get_group_name(pctldev,
 261                                         setting->data.configs.group_or_pin),
 262                            setting->data.configs.group_or_pin);
 263                 break;
 264         default:
 265                 break;
 266         }
 267
 268         /*
 269          * FIXME: We should really get the pin controler to dump the config
 270          * values, so they can be decoded to something meaningful.
 271          */
 272         for (i = 0; i < setting->data.configs.num_configs; i++) {
 273                 seq_printf(s, " ");
 274                 if (confops && confops->pin_config_config_dbg_show)
 275                         confops->pin_config_config_dbg_show(pctldev, s,
 276                                 setting->data.configs.configs[i]);
 277                 else
 278                         seq_printf(s, "%08lx",
 279                                    setting->data.configs.configs[i]);
 280         }
 281
 282         seq_printf(s, "\n");
 283 }
 284
 285 static void pinconf_dump_pin(struct pinctrl_dev *pctldev,
 286                              struct seq_file *s, int pin)
 287 {
 288         const struct pinconf_ops *ops = pctldev->desc->confops;
 289
 290         /* no-op when not using generic pin config */
 291         pinconf_generic_dump_pin(pctldev, s, pin);
 292         if (ops && ops->pin_config_dbg_show)
 293                 ops->pin_config_dbg_show(pctldev, s, pin);
 294 }
 295
 296 static int pinconf_pins_show(struct seq_file *s, void *what)
 297 {
 298         struct pinctrl_dev *pctldev = s->private;
 299         unsigned i, pin;
 300
 301         seq_puts(s, "Pin config settings per pin\n");
 302         seq_puts(s, "Format: pin (name): configs\n");
 303
 304         mutex_lock(&pctldev->mutex);
 305
 306         /* The pin number can be retrived from the pin controller descriptor */
 307         for (i = 0; i < pctldev->desc->npins; i++) {
 308                 struct pin_desc *desc;
 309
 310                 pin = pctldev->desc->pins[i].number;
 311                 desc = pin_desc_get(pctldev, pin);
 312                 /* Skip if we cannot search the pin */
 313                 if (desc == NULL)
 314                         continue;
 315
 316                 seq_printf(s, "pin %d (%s):", pin,
 317                            desc->name ? desc->name : "unnamed");
 318
 319                 pinconf_dump_pin(pctldev, s, pin);
 320
 321                 seq_printf(s, "\n");
 322         }
 323
 324         mutex_unlock(&pctldev->mutex);
 325
 326         return 0;
 327 }
 328
 329 static void pinconf_dump_group(struct pinctrl_dev *pctldev,
 330                                struct seq_file *s, unsigned selector,
 331                                const char *gname)
 332 {
 333         const struct pinconf_ops *ops = pctldev->desc->confops;
 334
 335         /* no-op when not using generic pin config */
 336         pinconf_generic_dump_group(pctldev, s, gname);
 337         if (ops && ops->pin_config_group_dbg_show)
 338                 ops->pin_config_group_dbg_show(pctldev, s, selector);
 339 }
 340
 341 static int pinconf_groups_show(struct seq_file *s, void *what)
 342 {
 343         struct pinctrl_dev *pctldev = s->private;
 344         const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
 345         unsigned ngroups = pctlops->get_groups_count(pctldev);
 346         unsigned selector = 0;
 347
 348         seq_puts(s, "Pin config settings per pin group\n");
 349         seq_puts(s, "Format: group (name): configs\n");
 350
 351         while (selector < ngroups) {
 352                 const char *gname = pctlops->get_group_name(pctldev, selector);
 353
 354                 seq_printf(s, "%u (%s):", selector, gname);
 355                 pinconf_dump_group(pctldev, s, selector, gname);
 356                 seq_printf(s, "\n");
 357
 358                 selector++;
 359         }
 360
 361         return 0;
 362 }
 363
 364 static int pinconf_pins_open(struct inode *inode, struct file *file)
 365 {
 366         return single_open(file, pinconf_pins_show, inode->i_private);
 367 }
 368
 369 static int pinconf_groups_open(struct inode *inode, struct file *file)
 370 {
 371         return single_open(file, pinconf_groups_show, inode->i_private);
 372 }
 373
 374 static const struct file_operations pinconf_pins_ops = {
 375         .open           = pinconf_pins_open,
 376         .read           = seq_read,
 377         .llseek         = seq_lseek,
 378         .release        = single_release,
 379 };
 380
 381 static const struct file_operations pinconf_groups_ops = {
 382         .open           = pinconf_groups_open,
 383         .read           = seq_read,
 384         .llseek         = seq_lseek,
 385         .release        = single_release,
 386 };
 387
 388 #define MAX_NAME_LEN 15
 389
 390 struct dbg_cfg {
 391         enum pinctrl_map_type map_type;
 392         char dev_name[MAX_NAME_LEN+1];
 393         char state_name[MAX_NAME_LEN+1];
 394         char pin_name[MAX_NAME_LEN+1];
 395 };
 396
 397 /*
 398  * Goal is to keep this structure as global in order to simply read the
 399  * pinconf-config file after a write to check config is as expected
 400  */
 401 static struct dbg_cfg pinconf_dbg_conf;
 402
 403 /**
 404  * pinconf_dbg_config_print() - display the pinctrl config from the pinctrl
 405  * map, of the dev/pin/state that was last written to pinconf-config file.
 406  * @s: string filled in  with config description
 407  * @d: not used
 408  */
 409 static int pinconf_dbg_config_print(struct seq_file *s, void *d)
 410 {
 411         struct pinctrl_maps *maps_node;
 412         const struct pinctrl_map *map;
 413         const struct pinctrl_map *found = NULL;
 414         struct pinctrl_dev *pctldev;
 415         const struct pinconf_ops *confops = NULL;
 416         struct dbg_cfg *dbg = &pinconf_dbg_conf;
 417         int i, j;
 418         unsigned long config;
 419
 420         mutex_lock(&pinctrl_maps_mutex);
 421
 422         /* Parse the pinctrl map and look for the elected pin/state */
 423         for_each_maps(maps_node, i, map) {
 424                 if (map->type != dbg->map_type)
 425                         continue;
 426                 if (strcmp(map->dev_name, dbg->dev_name))
 427                         continue;
 428                 if (strcmp(map->name, dbg->state_name))
 429                         continue;
 430
 431                 for (j = 0; j < map->data.configs.num_configs; j++) {
 432                         if (!strcmp(map->data.configs.group_or_pin,
 433                                         dbg->pin_name)) {
 434                                 /* We found the right pin / state */
 435                                 found = map;
 436                                 break;
 437                         }
 438                 }
 439         }
 440
 441         if (!found) {
 442                 seq_printf(s, "No config found for dev/state/pin, expected:\n");
 443                 seq_printf(s, "Searched dev:%s\n", dbg->dev_name);
 444                 seq_printf(s, "Searched state:%s\n", dbg->state_name);
 445                 seq_printf(s, "Searched pin:%s\n", dbg->pin_name);
 446                 seq_printf(s, "Use: modify config_pin <devname> "\
 447                                 "<state> <pinname> <value>\n");
 448                 goto exit;
 449         }
 450
 451         pctldev = get_pinctrl_dev_from_devname(found->ctrl_dev_name);
 452         config = *found->data.configs.configs;
 453         seq_printf(s, "Dev %s has config of %s in state %s: 0x%08lX\n",
 454                         dbg->dev_name, dbg->pin_name,
 455                         dbg->state_name, config);
 456
 457         if (pctldev)
 458                 confops = pctldev->desc->confops;
 459
 460         if (confops && confops->pin_config_config_dbg_show)
 461                 confops->pin_config_config_dbg_show(pctldev, s, config);
 462
 463 exit:
 464         mutex_unlock(&pinctrl_maps_mutex);
 465
 466         return 0;
 467 }
 468
 469 /**
 470  * pinconf_dbg_config_write() - modify the pinctrl config in the pinctrl
 471  * map, of a dev/pin/state entry based on user entries to pinconf-config
 472  * @user_buf: contains the modification request with expected format:
 473  *     modify config_pin <devicename> <state> <pinname> <newvalue>
 474  * modify is literal string, alternatives like add/delete not supported yet
 475  * config_pin is literal, alternatives like config_mux not supported yet
 476  * <devicename> <state> <pinname> are values that should match the pinctrl-maps
 477  * <newvalue> reflects the new config and is driver dependant
 478  */
 479 static ssize_t pinconf_dbg_config_write(struct file *file,
 480         const char __user *user_buf, size_t count, loff_t *ppos)
 481 {
 482         struct pinctrl_maps *maps_node;
 483         const struct pinctrl_map *map;
 484         const struct pinctrl_map *found = NULL;
 485         struct pinctrl_dev *pctldev;
 486         const struct pinconf_ops *confops = NULL;
 487         struct dbg_cfg *dbg = &pinconf_dbg_conf;
 488         const struct pinctrl_map_configs *configs;
 489         char config[MAX_NAME_LEN+1];
 490         char buf[128];
 491         char *b = &buf[0];
 492         int buf_size;
 493         char *token;
 494         int i;
 495
 496         /* Get userspace string and assure termination */
 497         buf_size = min(count, sizeof(buf) - 1);
 498         if (copy_from_user(buf, user_buf, buf_size))
 499                 return -EFAULT;
 500         buf[buf_size] = 0;
 501
 502         /*
 503          * need to parse entry and extract parameters:
 504          * modify configs_pin devicename state pinname newvalue
 505          */
 506
 507         /* Get arg: 'modify' */
 508         token = strsep(&b, " ");
 509         if (!token)
 510                 return -EINVAL;
 511         if (strcmp(token, "modify"))
 512                 return -EINVAL;
 513
 514         /* Get arg type: "config_pin" type supported so far */
 515         token = strsep(&b, " ");
 516         if (!token)
 517                 return -EINVAL;
 518         if (strcmp(token, "config_pin"))
 519                 return -EINVAL;
 520         dbg->map_type = PIN_MAP_TYPE_CONFIGS_PIN;
 521
 522         /* get arg 'device_name' */
 523         token = strsep(&b, " ");
 524         if (token == NULL)
 525                 return -EINVAL;
 526         if (strlen(token) >= MAX_NAME_LEN)
 527                 return -EINVAL;
 528         strncpy(dbg->dev_name, token, MAX_NAME_LEN);
 529
 530         /* get arg 'state_name' */
 531         token = strsep(&b, " ");
 532         if (token == NULL)
 533                 return -EINVAL;
 534         if (strlen(token) >= MAX_NAME_LEN)
 535                 return -EINVAL;
 536         strncpy(dbg->state_name, token, MAX_NAME_LEN);
 537
 538         /* get arg 'pin_name' */
 539         token = strsep(&b, " ");
 540         if (token == NULL)
 541                 return -EINVAL;
 542         if (strlen(token) >= MAX_NAME_LEN)
 543                 return -EINVAL;
 544         strncpy(dbg->pin_name, token, MAX_NAME_LEN);
 545
 546         /* get new_value of config' */
 547         token = strsep(&b, " ");
 548         if (token == NULL)
 549                 return -EINVAL;
 550         if (strlen(token) >= MAX_NAME_LEN)
 551                 return -EINVAL;
 552         strncpy(config, token, MAX_NAME_LEN);
 553
 554         mutex_lock(&pinctrl_maps_mutex);
 555
 556         /* Parse the pinctrl map and look for the selected dev/state/pin */
 557         for_each_maps(maps_node, i, map) {
 558                 if (strcmp(map->dev_name, dbg->dev_name))
 559                         continue;
 560                 if (map->type != dbg->map_type)
 561                         continue;
 562                 if (strcmp(map->name, dbg->state_name))
 563                         continue;
 564
 565                 /*  we found the right pin / state, so overwrite config */
 566                 if (!strcmp(map->data.configs.group_or_pin, dbg->pin_name)) {
 567                         found = map;
 568                         break;
 569                 }
 570         }
 571
 572         if (!found) {
 573                 count = -EINVAL;
 574                 goto exit;
 575         }
 576
 577         pctldev = get_pinctrl_dev_from_devname(found->ctrl_dev_name);
 578         if (pctldev)
 579                 confops = pctldev->desc->confops;
 580
 581         if (confops && confops->pin_config_dbg_parse_modify) {
 582                 configs = &found->data.configs;
 583                 for (i = 0; i < configs->num_configs; i++) {
 584                         confops->pin_config_dbg_parse_modify(pctldev,
 585                                                      config,
 586                                                      &configs->configs[i]);
 587                 }
 588         }
 589
 590 exit:
 591         mutex_unlock(&pinctrl_maps_mutex);
 592
 593         return count;
 594 }
 595
 596 static int pinconf_dbg_config_open(struct inode *inode, struct file *file)
 597 {
 598         return single_open(file, pinconf_dbg_config_print, inode->i_private);
 599 }
 600
 601 static const struct file_operations pinconf_dbg_pinconfig_fops = {
 602         .open = pinconf_dbg_config_open,
 603         .write = pinconf_dbg_config_write,
 604         .read = seq_read,
 605         .llseek = seq_lseek,
 606         .release = single_release,
 607         .owner = THIS_MODULE,
 608 };
 609
 610 void pinconf_init_device_debugfs(struct dentry *devroot,
 611                          struct pinctrl_dev *pctldev)
 612 {
 613         debugfs_create_file("pinconf-pins", S_IFREG | S_IRUGO,
 614                             devroot, pctldev, &pinconf_pins_ops);
 615         debugfs_create_file("pinconf-groups", S_IFREG | S_IRUGO,
 616                             devroot, pctldev, &pinconf_groups_ops);
 617         debugfs_create_file("pinconf-config",  (S_IRUGO | S_IWUSR | S_IWGRP),
 618                             devroot, pctldev, &pinconf_dbg_pinconfig_fops);
 619 }
 620
 621 #endif