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 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                 ret = ops->pin_config_set(pctldev,
 175                                 setting->data.configs.group_or_pin,
 176                                 setting->data.configs.configs,
 177                                 setting->data.configs.num_configs);
 178                 if (ret < 0) {
 179                         dev_err(pctldev->dev,
 180                                 "pin_config_set op failed for pin %d\n",
 181                                 setting->data.configs.group_or_pin);
 182                         return ret;
 183                 }
 184                 break;
 185         case PIN_MAP_TYPE_CONFIGS_GROUP:
 186                 if (!ops->pin_config_group_set) {
 187                         dev_err(pctldev->dev,
 188                                 "missing pin_config_group_set op\n");
 189                         return -EINVAL;
 190                 }
 191                 ret = ops->pin_config_group_set(pctldev,
 192                                 setting->data.configs.group_or_pin,
 193                                 setting->data.configs.configs,
 194                                 setting->data.configs.num_configs);
 195                 if (ret < 0) {
 196                         dev_err(pctldev->dev,
 197                                 "pin_config_group_set op failed for group %d\n",
 198                                 setting->data.configs.group_or_pin);
 199                         return ret;
 200                 }
 201                 break;
 202         default:
 203                 return -EINVAL;
 204         }
 205
 206         return 0;
 207 }
 208
 209 #ifdef CONFIG_DEBUG_FS
 210
 211 void pinconf_show_map(struct seq_file *s, struct pinctrl_map const *map)
 212 {
 213         struct pinctrl_dev *pctldev;
 214         const struct pinconf_ops *confops;
 215         int i;
 216
 217         pctldev = get_pinctrl_dev_from_devname(map->ctrl_dev_name);
 218         if (pctldev)
 219                 confops = pctldev->desc->confops;
 220         else
 221                 confops = NULL;
 222
 223         switch (map->type) {
 224         case PIN_MAP_TYPE_CONFIGS_PIN:
 225                 seq_printf(s, "pin ");
 226                 break;
 227         case PIN_MAP_TYPE_CONFIGS_GROUP:
 228                 seq_printf(s, "group ");
 229                 break;
 230         default:
 231                 break;
 232         }
 233
 234         seq_printf(s, "%s\n", map->data.configs.group_or_pin);
 235
 236         for (i = 0; i < map->data.configs.num_configs; i++) {
 237                 seq_printf(s, "config ");
 238                 if (confops && confops->pin_config_config_dbg_show)
 239                         confops->pin_config_config_dbg_show(pctldev, s,
 240                                                 map->data.configs.configs[i]);
 241                 else
 242                         seq_printf(s, "%08lx", map->data.configs.configs[i]);
 243                 seq_printf(s, "\n");
 244         }
 245 }
 246
 247 void pinconf_show_setting(struct seq_file *s,
 248                           struct pinctrl_setting const *setting)
 249 {
 250         struct pinctrl_dev *pctldev = setting->pctldev;
 251         const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
 252         const struct pinconf_ops *confops = pctldev->desc->confops;
 253         struct pin_desc *desc;
 254         int i;
 255
 256         switch (setting->type) {
 257         case PIN_MAP_TYPE_CONFIGS_PIN:
 258                 desc = pin_desc_get(setting->pctldev,
 259                                     setting->data.configs.group_or_pin);
 260                 seq_printf(s, "pin %s (%d)",
 261                            desc->name ? desc->name : "unnamed",
 262                            setting->data.configs.group_or_pin);
 263                 break;
 264         case PIN_MAP_TYPE_CONFIGS_GROUP:
 265                 seq_printf(s, "group %s (%d)",
 266                            pctlops->get_group_name(pctldev,
 267                                         setting->data.configs.group_or_pin),
 268                            setting->data.configs.group_or_pin);
 269                 break;
 270         default:
 271                 break;
 272         }
 273
 274         /*
 275          * FIXME: We should really get the pin controler to dump the config
 276          * values, so they can be decoded to something meaningful.
 277          */
 278         for (i = 0; i < setting->data.configs.num_configs; i++) {
 279                 seq_printf(s, " ");
 280                 if (confops && confops->pin_config_config_dbg_show)
 281                         confops->pin_config_config_dbg_show(pctldev, s,
 282                                 setting->data.configs.configs[i]);
 283                 else
 284                         seq_printf(s, "%08lx",
 285                                    setting->data.configs.configs[i]);
 286         }
 287
 288         seq_printf(s, "\n");
 289 }
 290
 291 static void pinconf_dump_pin(struct pinctrl_dev *pctldev,
 292                              struct seq_file *s, int pin)
 293 {
 294         const struct pinconf_ops *ops = pctldev->desc->confops;
 295
 296         /* no-op when not using generic pin config */
 297         pinconf_generic_dump_pin(pctldev, s, pin);
 298         if (ops && ops->pin_config_dbg_show)
 299                 ops->pin_config_dbg_show(pctldev, s, pin);
 300 }
 301
 302 static int pinconf_pins_show(struct seq_file *s, void *what)
 303 {
 304         struct pinctrl_dev *pctldev = s->private;
 305         const struct pinconf_ops *ops = pctldev->desc->confops;
 306         unsigned i, pin;
 307
 308         if (!ops || !ops->pin_config_get)
 309                 return 0;
 310
 311         seq_puts(s, "Pin config settings per pin\n");
 312         seq_puts(s, "Format: pin (name): configs\n");
 313
 314         mutex_lock(&pctldev->mutex);
 315
 316         /* The pin number can be retrived from the pin controller descriptor */
 317         for (i = 0; i < pctldev->desc->npins; i++) {
 318                 struct pin_desc *desc;
 319
 320                 pin = pctldev->desc->pins[i].number;
 321                 desc = pin_desc_get(pctldev, pin);
 322                 /* Skip if we cannot search the pin */
 323                 if (desc == NULL)
 324                         continue;
 325
 326                 seq_printf(s, "pin %d (%s):", pin,
 327                            desc->name ? desc->name : "unnamed");
 328
 329                 pinconf_dump_pin(pctldev, s, pin);
 330
 331                 seq_printf(s, "\n");
 332         }
 333
 334         mutex_unlock(&pctldev->mutex);
 335
 336         return 0;
 337 }
 338
 339 static void pinconf_dump_group(struct pinctrl_dev *pctldev,
 340                                struct seq_file *s, unsigned selector,
 341                                const char *gname)
 342 {
 343         const struct pinconf_ops *ops = pctldev->desc->confops;
 344
 345         /* no-op when not using generic pin config */
 346         pinconf_generic_dump_group(pctldev, s, gname);
 347         if (ops && ops->pin_config_group_dbg_show)
 348                 ops->pin_config_group_dbg_show(pctldev, s, selector);
 349 }
 350
 351 static int pinconf_groups_show(struct seq_file *s, void *what)
 352 {
 353         struct pinctrl_dev *pctldev = s->private;
 354         const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
 355         const struct pinconf_ops *ops = pctldev->desc->confops;
 356         unsigned ngroups = pctlops->get_groups_count(pctldev);
 357         unsigned selector = 0;
 358
 359         if (!ops || !ops->pin_config_group_get)
 360                 return 0;
 361
 362         seq_puts(s, "Pin config settings per pin group\n");
 363         seq_puts(s, "Format: group (name): configs\n");
 364
 365         while (selector < ngroups) {
 366                 const char *gname = pctlops->get_group_name(pctldev, selector);
 367
 368                 seq_printf(s, "%u (%s):", selector, gname);
 369                 pinconf_dump_group(pctldev, s, selector, gname);
 370                 seq_printf(s, "\n");
 371
 372                 selector++;
 373         }
 374
 375         return 0;
 376 }
 377
 378 static int pinconf_pins_open(struct inode *inode, struct file *file)
 379 {
 380         return single_open(file, pinconf_pins_show, inode->i_private);
 381 }
 382
 383 static int pinconf_groups_open(struct inode *inode, struct file *file)
 384 {
 385         return single_open(file, pinconf_groups_show, inode->i_private);
 386 }
 387
 388 static const struct file_operations pinconf_pins_ops = {
 389         .open           = pinconf_pins_open,
 390         .read           = seq_read,
 391         .llseek         = seq_lseek,
 392         .release        = single_release,
 393 };
 394
 395 static const struct file_operations pinconf_groups_ops = {
 396         .open           = pinconf_groups_open,
 397         .read           = seq_read,
 398         .llseek         = seq_lseek,
 399         .release        = single_release,
 400 };
 401
 402 #define MAX_NAME_LEN 15
 403
 404 struct dbg_cfg {
 405         enum pinctrl_map_type map_type;
 406         char dev_name[MAX_NAME_LEN+1];
 407         char state_name[MAX_NAME_LEN+1];
 408         char pin_name[MAX_NAME_LEN+1];
 409 };
 410
 411 /*
 412  * Goal is to keep this structure as global in order to simply read the
 413  * pinconf-config file after a write to check config is as expected
 414  */
 415 static struct dbg_cfg pinconf_dbg_conf;
 416
 417 /**
 418  * pinconf_dbg_config_print() - display the pinctrl config from the pinctrl
 419  * map, of the dev/pin/state that was last written to pinconf-config file.
 420  * @s: string filled in  with config description
 421  * @d: not used
 422  */
 423 static int pinconf_dbg_config_print(struct seq_file *s, void *d)
 424 {
 425         struct pinctrl_maps *maps_node;
 426         const struct pinctrl_map *map;
 427         const struct pinctrl_map *found = NULL;
 428         struct pinctrl_dev *pctldev;
 429         const struct pinconf_ops *confops = NULL;
 430         struct dbg_cfg *dbg = &pinconf_dbg_conf;
 431         int i, j;
 432         unsigned long config;
 433
 434         mutex_lock(&pinctrl_maps_mutex);
 435
 436         /* Parse the pinctrl map and look for the elected pin/state */
 437         for_each_maps(maps_node, i, map) {
 438                 if (map->type != dbg->map_type)
 439                         continue;
 440                 if (strcmp(map->dev_name, dbg->dev_name))
 441                         continue;
 442                 if (strcmp(map->name, dbg->state_name))
 443                         continue;
 444
 445                 for (j = 0; j < map->data.configs.num_configs; j++) {
 446                         if (!strcmp(map->data.configs.group_or_pin,
 447                                         dbg->pin_name)) {
 448                                 /* We found the right pin / state */
 449                                 found = map;
 450                                 break;
 451                         }
 452                 }
 453         }
 454
 455         if (!found) {
 456                 seq_printf(s, "No config found for dev/state/pin, expected:\n");
 457                 seq_printf(s, "Searched dev:%s\n", dbg->dev_name);
 458                 seq_printf(s, "Searched state:%s\n", dbg->state_name);
 459                 seq_printf(s, "Searched pin:%s\n", dbg->pin_name);
 460                 seq_printf(s, "Use: modify config_pin <devname> "\
 461                                 "<state> <pinname> <value>\n");
 462                 goto exit;
 463         }
 464
 465         pctldev = get_pinctrl_dev_from_devname(found->ctrl_dev_name);
 466         config = *found->data.configs.configs;
 467         seq_printf(s, "Dev %s has config of %s in state %s: 0x%08lX\n",
 468                         dbg->dev_name, dbg->pin_name,
 469                         dbg->state_name, config);
 470
 471         if (pctldev)
 472                 confops = pctldev->desc->confops;
 473
 474         if (confops && confops->pin_config_config_dbg_show)
 475                 confops->pin_config_config_dbg_show(pctldev, s, config);
 476
 477 exit:
 478         mutex_unlock(&pinctrl_maps_mutex);
 479
 480         return 0;
 481 }
 482
 483 /**
 484  * pinconf_dbg_config_write() - modify the pinctrl config in the pinctrl
 485  * map, of a dev/pin/state entry based on user entries to pinconf-config
 486  * @user_buf: contains the modification request with expected format:
 487  *     modify config_pin <devicename> <state> <pinname> <newvalue>
 488  * modify is literal string, alternatives like add/delete not supported yet
 489  * config_pin is literal, alternatives like config_mux not supported yet
 490  * <devicename> <state> <pinname> are values that should match the pinctrl-maps
 491  * <newvalue> reflects the new config and is driver dependant
 492  */
 493 static ssize_t pinconf_dbg_config_write(struct file *file,
 494         const char __user *user_buf, size_t count, loff_t *ppos)
 495 {
 496         struct pinctrl_maps *maps_node;
 497         const struct pinctrl_map *map;
 498         const struct pinctrl_map *found = NULL;
 499         struct pinctrl_dev *pctldev;
 500         const struct pinconf_ops *confops = NULL;
 501         struct dbg_cfg *dbg = &pinconf_dbg_conf;
 502         const struct pinctrl_map_configs *configs;
 503         char config[MAX_NAME_LEN+1];
 504         char buf[128];
 505         char *b = &buf[0];
 506         int buf_size;
 507         char *token;
 508         int i;
 509
 510         /* Get userspace string and assure termination */
 511         buf_size = min(count, sizeof(buf) - 1);
 512         if (copy_from_user(buf, user_buf, buf_size))
 513                 return -EFAULT;
 514         buf[buf_size] = 0;
 515
 516         /*
 517          * need to parse entry and extract parameters:
 518          * modify configs_pin devicename state pinname newvalue
 519          */
 520
 521         /* Get arg: 'modify' */
 522         token = strsep(&b, " ");
 523         if (!token)
 524                 return -EINVAL;
 525         if (strcmp(token, "modify"))
 526                 return -EINVAL;
 527
 528         /* Get arg type: "config_pin" type supported so far */
 529         token = strsep(&b, " ");
 530         if (!token)
 531                 return -EINVAL;
 532         if (strcmp(token, "config_pin"))
 533                 return -EINVAL;
 534         dbg->map_type = PIN_MAP_TYPE_CONFIGS_PIN;
 535
 536         /* get arg 'device_name' */
 537         token = strsep(&b, " ");
 538         if (token == NULL)
 539                 return -EINVAL;
 540         if (strlen(token) >= MAX_NAME_LEN)
 541                 return -EINVAL;
 542         strncpy(dbg->dev_name, token, MAX_NAME_LEN);
 543
 544         /* get arg 'state_name' */
 545         token = strsep(&b, " ");
 546         if (token == NULL)
 547                 return -EINVAL;
 548         if (strlen(token) >= MAX_NAME_LEN)
 549                 return -EINVAL;
 550         strncpy(dbg->state_name, token, MAX_NAME_LEN);
 551
 552         /* get arg 'pin_name' */
 553         token = strsep(&b, " ");
 554         if (token == NULL)
 555                 return -EINVAL;
 556         if (strlen(token) >= MAX_NAME_LEN)
 557                 return -EINVAL;
 558         strncpy(dbg->pin_name, token, MAX_NAME_LEN);
 559
 560         /* get new_value of config' */
 561         token = strsep(&b, " ");
 562         if (token == NULL)
 563                 return -EINVAL;
 564         if (strlen(token) >= MAX_NAME_LEN)
 565                 return -EINVAL;
 566         strncpy(config, token, MAX_NAME_LEN);
 567
 568         mutex_lock(&pinctrl_maps_mutex);
 569
 570         /* Parse the pinctrl map and look for the selected dev/state/pin */
 571         for_each_maps(maps_node, i, map) {
 572                 if (strcmp(map->dev_name, dbg->dev_name))
 573                         continue;
 574                 if (map->type != dbg->map_type)
 575                         continue;
 576                 if (strcmp(map->name, dbg->state_name))
 577                         continue;
 578
 579                 /*  we found the right pin / state, so overwrite config */
 580                 if (!strcmp(map->data.configs.group_or_pin, dbg->pin_name)) {
 581                         found = map;
 582                         break;
 583                 }
 584         }
 585
 586         if (!found) {
 587                 count = -EINVAL;
 588                 goto exit;
 589         }
 590
 591         pctldev = get_pinctrl_dev_from_devname(found->ctrl_dev_name);
 592         if (pctldev)
 593                 confops = pctldev->desc->confops;
 594
 595         if (confops && confops->pin_config_dbg_parse_modify) {
 596                 configs = &found->data.configs;
 597                 for (i = 0; i < configs->num_configs; i++) {
 598                         confops->pin_config_dbg_parse_modify(pctldev,
 599                                                      config,
 600                                                      &configs->configs[i]);
 601                 }
 602         }
 603
 604 exit:
 605         mutex_unlock(&pinctrl_maps_mutex);
 606
 607         return count;
 608 }
 609
 610 static int pinconf_dbg_config_open(struct inode *inode, struct file *file)
 611 {
 612         return single_open(file, pinconf_dbg_config_print, inode->i_private);
 613 }
 614
 615 static const struct file_operations pinconf_dbg_pinconfig_fops = {
 616         .open = pinconf_dbg_config_open,
 617         .write = pinconf_dbg_config_write,
 618         .read = seq_read,
 619         .llseek = seq_lseek,
 620         .release = single_release,
 621         .owner = THIS_MODULE,
 622 };
 623
 624 void pinconf_init_device_debugfs(struct dentry *devroot,
 625                          struct pinctrl_dev *pctldev)
 626 {
 627         debugfs_create_file("pinconf-pins", S_IFREG | S_IRUGO,
 628                             devroot, pctldev, &pinconf_pins_ops);
 629         debugfs_create_file("pinconf-groups", S_IFREG | S_IRUGO,
 630                             devroot, pctldev, &pinconf_groups_ops);
 631         debugfs_create_file("pinconf-config",  (S_IRUGO | S_IWUSR | S_IWGRP),
 632                             devroot, pctldev, &pinconf_dbg_pinconfig_fops);
 633 }
 634
 635 #endif