linux/drivers/pinctrl/pinconf.c
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   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
  27int 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
  46int 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
  64int 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
  78int 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
 111unlock:
 112        mutex_unlock(&pctldev->mutex);
 113        return ret;
 114}
 115
 116int 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
 153void pinconf_free_setting(struct pinctrl_setting const *setting)
 154{
 155}
 156
 157int 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
 211void 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
 247void 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
 291static 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
 302static 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
 339static 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
 351static 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
 378static int pinconf_pins_open(struct inode *inode, struct file *file)
 379{
 380        return single_open(file, pinconf_pins_show, inode->i_private);
 381}
 382
 383static int pinconf_groups_open(struct inode *inode, struct file *file)
 384{
 385        return single_open(file, pinconf_groups_show, inode->i_private);
 386}
 387
 388static 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
 395static 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
 404struct 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 */
 415static 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 */
 423static 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
 477exit:
 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 */
 493static 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
 604exit:
 605        mutex_unlock(&pinctrl_maps_mutex);
 606
 607        return count;
 608}
 609
 610static 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
 615static 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
 624void 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
 636
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