drivers/firewire/core-device.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Device probing and sysfs code.
   4  *
   5  * Copyright (C) 2005-2006  Kristian Hoegsberg <[email protected]>
   6  */
   7
   8 #include <linux/bug.h>
   9 #include <linux/ctype.h>
  10 #include <linux/delay.h>
  11 #include <linux/device.h>
  12 #include <linux/errno.h>
  13 #include <linux/firewire.h>
  14 #include <linux/firewire-constants.h>
  15 #include <linux/jiffies.h>
  16 #include <linux/kobject.h>
  17 #include <linux/list.h>
  18 #include <linux/mod_devicetable.h>
  19 #include <linux/module.h>
  20 #include <linux/mutex.h>
  21 #include <linux/random.h>
  22 #include <linux/rwsem.h>
  23 #include <linux/slab.h>
  24 #include <linux/spinlock.h>
  25 #include <linux/string.h>
  26 #include <linux/workqueue.h>
  27
  28 #include <linux/atomic.h>
  29 #include <asm/byteorder.h>
  30
  31 #include "core.h"
  32
  33 #define ROOT_DIR_OFFSET 5
  34
  35 void fw_csr_iterator_init(struct fw_csr_iterator *ci, const u32 *p)
  36 {
  37         ci->p = p + 1;
  38         ci->end = ci->p + (p[0] >> 16);
  39 }
  40 EXPORT_SYMBOL(fw_csr_iterator_init);
  41
  42 int fw_csr_iterator_next(struct fw_csr_iterator *ci, int *key, int *value)
  43 {
  44         *key = *ci->p >> 24;
  45         *value = *ci->p & 0xffffff;
  46
  47         return ci->p++ < ci->end;
  48 }
  49 EXPORT_SYMBOL(fw_csr_iterator_next);
  50
  51 static const u32 *search_directory(const u32 *directory, int search_key)
  52 {
  53         struct fw_csr_iterator ci;
  54         int key, value;
  55
  56         search_key |= CSR_DIRECTORY;
  57
  58         fw_csr_iterator_init(&ci, directory);
  59         while (fw_csr_iterator_next(&ci, &key, &value)) {
  60                 if (key == search_key)
  61                         return ci.p - 1 + value;
  62         }
  63
  64         return NULL;
  65 }
  66
  67 static const u32 *search_leaf(const u32 *directory, int search_key)
  68 {
  69         struct fw_csr_iterator ci;
  70         int last_key = 0, key, value;
  71
  72         fw_csr_iterator_init(&ci, directory);
  73         while (fw_csr_iterator_next(&ci, &key, &value)) {
  74                 if (last_key == search_key &&
  75                     key == (CSR_DESCRIPTOR | CSR_LEAF))
  76                         return ci.p - 1 + value;
  77
  78                 last_key = key;
  79         }
  80
  81         return NULL;
  82 }
  83
  84 static int textual_leaf_to_string(const u32 *block, char *buf, size_t size)
  85 {
  86         unsigned int quadlets, i;
  87         char c;
  88
  89         if (!size || !buf)
  90                 return -EINVAL;
  91
  92         quadlets = min(block[0] >> 16, 256U);
  93         if (quadlets < 2)
  94                 return -ENODATA;
  95
  96         if (block[1] != 0 || block[2] != 0)
  97                 /* unknown language/character set */
  98                 return -ENODATA;
  99
 100         block += 3;
 101         quadlets -= 2;
 102         for (i = 0; i < quadlets * 4 && i < size - 1; i++) {
 103                 c = block[i / 4] >> (24 - 8 * (i % 4));
 104                 if (c == '\0')
 105                         break;
 106                 buf[i] = c;
 107         }
 108         buf[i] = '\0';
 109
 110         return i;
 111 }
 112
 113 /**
 114  * fw_csr_string() - reads a string from the configuration ROM
 115  * @directory:  e.g. root directory or unit directory
 116  * @key:        the key of the preceding directory entry
 117  * @buf:        where to put the string
 118  * @size:       size of @buf, in bytes
 119  *
 120  * The string is taken from a minimal ASCII text descriptor leaf just after the entry with the
 121  * @key. The string is zero-terminated. An overlong string is silently truncated such that it
 122  * and the zero byte fit into @size.
 123  *
 124  * Returns strlen(buf) or a negative error code.
 125  */
 126 int fw_csr_string(const u32 *directory, int key, char *buf, size_t size)
 127 {
 128         const u32 *leaf = search_leaf(directory, key);
 129         if (!leaf)
 130                 return -ENOENT;
 131
 132         return textual_leaf_to_string(leaf, buf, size);
 133 }
 134 EXPORT_SYMBOL(fw_csr_string);
 135
 136 static void get_ids(const u32 *directory, int *id)
 137 {
 138         struct fw_csr_iterator ci;
 139         int key, value;
 140
 141         fw_csr_iterator_init(&ci, directory);
 142         while (fw_csr_iterator_next(&ci, &key, &value)) {
 143                 switch (key) {
 144                 case CSR_VENDOR:        id[0] = value; break;
 145                 case CSR_MODEL:         id[1] = value; break;
 146                 case CSR_SPECIFIER_ID:  id[2] = value; break;
 147                 case CSR_VERSION:       id[3] = value; break;
 148                 }
 149         }
 150 }
 151
 152 static void get_modalias_ids(const struct fw_unit *unit, int *id)
 153 {
 154         const u32 *root_directory = &fw_parent_device(unit)->config_rom[ROOT_DIR_OFFSET];
 155         const u32 *directories[] = {NULL, NULL, NULL};
 156         const u32 *vendor_directory;
 157         int i;
 158
 159         directories[0] = root_directory;
 160
 161         // Legacy layout of configuration ROM described in Annex 1 of 'Configuration ROM for AV/C
 162         // Devices 1.0 (December 12, 2000, 1394 Trading Association, TA Document 1999027)'.
 163         vendor_directory = search_directory(root_directory, CSR_VENDOR);
 164         if (!vendor_directory) {
 165                 directories[1] = unit->directory;
 166         } else {
 167                 directories[1] = vendor_directory;
 168                 directories[2] = unit->directory;
 169         }
 170
 171         for (i = 0; i < ARRAY_SIZE(directories) && !!directories[i]; ++i)
 172                 get_ids(directories[i], id);
 173 }
 174
 175 static bool match_ids(const struct ieee1394_device_id *id_table, int *id)
 176 {
 177         int match = 0;
 178
 179         if (id[0] == id_table->vendor_id)
 180                 match |= IEEE1394_MATCH_VENDOR_ID;
 181         if (id[1] == id_table->model_id)
 182                 match |= IEEE1394_MATCH_MODEL_ID;
 183         if (id[2] == id_table->specifier_id)
 184                 match |= IEEE1394_MATCH_SPECIFIER_ID;
 185         if (id[3] == id_table->version)
 186                 match |= IEEE1394_MATCH_VERSION;
 187
 188         return (match & id_table->match_flags) == id_table->match_flags;
 189 }
 190
 191 static const struct ieee1394_device_id *unit_match(struct device *dev,
 192                                                    const struct device_driver *drv)
 193 {
 194         const struct ieee1394_device_id *id_table =
 195                         container_of_const(drv, struct fw_driver, driver)->id_table;
 196         int id[] = {0, 0, 0, 0};
 197
 198         get_modalias_ids(fw_unit(dev), id);
 199
 200         for (; id_table->match_flags != 0; id_table++)
 201                 if (match_ids(id_table, id))
 202                         return id_table;
 203
 204         return NULL;
 205 }
 206
 207 static bool is_fw_unit(const struct device *dev);
 208
 209 static int fw_unit_match(struct device *dev, const struct device_driver *drv)
 210 {
 211         /* We only allow binding to fw_units. */
 212         return is_fw_unit(dev) && unit_match(dev, drv) != NULL;
 213 }
 214
 215 static int fw_unit_probe(struct device *dev)
 216 {
 217         struct fw_driver *driver =
 218                         container_of(dev->driver, struct fw_driver, driver);
 219
 220         return driver->probe(fw_unit(dev), unit_match(dev, dev->driver));
 221 }
 222
 223 static void fw_unit_remove(struct device *dev)
 224 {
 225         struct fw_driver *driver =
 226                         container_of(dev->driver, struct fw_driver, driver);
 227
 228         driver->remove(fw_unit(dev));
 229 }
 230
 231 static int get_modalias(const struct fw_unit *unit, char *buffer, size_t buffer_size)
 232 {
 233         int id[] = {0, 0, 0, 0};
 234
 235         get_modalias_ids(unit, id);
 236
 237         return snprintf(buffer, buffer_size,
 238                         "ieee1394:ven%08Xmo%08Xsp%08Xver%08X",
 239                         id[0], id[1], id[2], id[3]);
 240 }
 241
 242 static int fw_unit_uevent(const struct device *dev, struct kobj_uevent_env *env)
 243 {
 244         const struct fw_unit *unit = fw_unit(dev);
 245         char modalias[64];
 246
 247         get_modalias(unit, modalias, sizeof(modalias));
 248
 249         if (add_uevent_var(env, "MODALIAS=%s", modalias))
 250                 return -ENOMEM;
 251
 252         return 0;
 253 }
 254
 255 const struct bus_type fw_bus_type = {
 256         .name = "firewire",
 257         .match = fw_unit_match,
 258         .probe = fw_unit_probe,
 259         .remove = fw_unit_remove,
 260 };
 261 EXPORT_SYMBOL(fw_bus_type);
 262
 263 int fw_device_enable_phys_dma(struct fw_device *device)
 264 {
 265         int generation = device->generation;
 266
 267         /* device->node_id, accessed below, must not be older than generation */
 268         smp_rmb();
 269
 270         return device->card->driver->enable_phys_dma(device->card,
 271                                                      device->node_id,
 272                                                      generation);
 273 }
 274 EXPORT_SYMBOL(fw_device_enable_phys_dma);
 275
 276 struct config_rom_attribute {
 277         struct device_attribute attr;
 278         u32 key;
 279 };
 280
 281 static ssize_t show_immediate(struct device *dev,
 282                               struct device_attribute *dattr, char *buf)
 283 {
 284         struct config_rom_attribute *attr =
 285                 container_of(dattr, struct config_rom_attribute, attr);
 286         struct fw_csr_iterator ci;
 287         const u32 *directories[] = {NULL, NULL};
 288         int i, value = -1;
 289
 290         guard(rwsem_read)(&fw_device_rwsem);
 291
 292         if (is_fw_unit(dev)) {
 293                 directories[0] = fw_unit(dev)->directory;
 294         } else {
 295                 const u32 *root_directory = fw_device(dev)->config_rom + ROOT_DIR_OFFSET;
 296                 const u32 *vendor_directory = search_directory(root_directory, CSR_VENDOR);
 297
 298                 if (!vendor_directory) {
 299                         directories[0] = root_directory;
 300                 } else {
 301                         // Legacy layout of configuration ROM described in Annex 1 of
 302                         // 'Configuration ROM for AV/C Devices 1.0 (December 12, 2000, 1394 Trading
 303                         // Association, TA Document 1999027)'.
 304                         directories[0] = vendor_directory;
 305                         directories[1] = root_directory;
 306                 }
 307         }
 308
 309         for (i = 0; i < ARRAY_SIZE(directories) && !!directories[i]; ++i) {
 310                 int key, val;
 311
 312                 fw_csr_iterator_init(&ci, directories[i]);
 313                 while (fw_csr_iterator_next(&ci, &key, &val)) {
 314                         if (attr->key == key)
 315                                 value = val;
 316                 }
 317         }
 318
 319         if (value < 0)
 320                 return -ENOENT;
 321
 322         // Note that this function is also called by init_fw_attribute_group() with NULL pointer.
 323         return buf ? sysfs_emit(buf, "0x%06x\n", value) : 0;
 324 }
 325
 326 #define IMMEDIATE_ATTR(name, key)                               \
 327         { __ATTR(name, S_IRUGO, show_immediate, NULL), key }
 328
 329 static ssize_t show_text_leaf(struct device *dev,
 330                               struct device_attribute *dattr, char *buf)
 331 {
 332         struct config_rom_attribute *attr =
 333                 container_of(dattr, struct config_rom_attribute, attr);
 334         const u32 *directories[] = {NULL, NULL};
 335         size_t bufsize;
 336         char dummy_buf[2];
 337         int i, ret = -ENOENT;
 338
 339         guard(rwsem_read)(&fw_device_rwsem);
 340
 341         if (is_fw_unit(dev)) {
 342                 directories[0] = fw_unit(dev)->directory;
 343         } else {
 344                 const u32 *root_directory = fw_device(dev)->config_rom + ROOT_DIR_OFFSET;
 345                 const u32 *vendor_directory = search_directory(root_directory, CSR_VENDOR);
 346
 347                 if (!vendor_directory) {
 348                         directories[0] = root_directory;
 349                 } else {
 350                         // Legacy layout of configuration ROM described in Annex 1 of
 351                         // 'Configuration ROM for AV/C Devices 1.0 (December 12, 2000, 1394
 352                         // Trading Association, TA Document 1999027)'.
 353                         directories[0] = root_directory;
 354                         directories[1] = vendor_directory;
 355                 }
 356         }
 357
 358         // Note that this function is also called by init_fw_attribute_group() with NULL pointer.
 359         if (buf) {
 360                 bufsize = PAGE_SIZE - 1;
 361         } else {
 362                 buf = dummy_buf;
 363                 bufsize = 1;
 364         }
 365
 366         for (i = 0; i < ARRAY_SIZE(directories) && !!directories[i]; ++i) {
 367                 int result = fw_csr_string(directories[i], attr->key, buf, bufsize);
 368                 // Detected.
 369                 if (result >= 0) {
 370                         ret = result;
 371                 } else if (i == 0 && attr->key == CSR_VENDOR) {
 372                         // Sony DVMC-DA1 has configuration ROM such that the descriptor leaf entry
 373                         // in the root directory follows to the directory entry for vendor ID
 374                         // instead of the immediate value for vendor ID.
 375                         result = fw_csr_string(directories[i], CSR_DIRECTORY | attr->key, buf,
 376                                                bufsize);
 377                         if (result >= 0)
 378                                 ret = result;
 379                 }
 380         }
 381
 382         if (ret < 0)
 383                 return ret;
 384
 385         // Strip trailing whitespace and add newline.
 386         while (ret > 0 && isspace(buf[ret - 1]))
 387                 ret--;
 388         strcpy(buf + ret, "\n");
 389         ret++;
 390
 391         return ret;
 392 }
 393
 394 #define TEXT_LEAF_ATTR(name, key)                               \
 395         { __ATTR(name, S_IRUGO, show_text_leaf, NULL), key }
 396
 397 static struct config_rom_attribute config_rom_attributes[] = {
 398         IMMEDIATE_ATTR(vendor, CSR_VENDOR),
 399         IMMEDIATE_ATTR(hardware_version, CSR_HARDWARE_VERSION),
 400         IMMEDIATE_ATTR(specifier_id, CSR_SPECIFIER_ID),
 401         IMMEDIATE_ATTR(version, CSR_VERSION),
 402         IMMEDIATE_ATTR(model, CSR_MODEL),
 403         TEXT_LEAF_ATTR(vendor_name, CSR_VENDOR),
 404         TEXT_LEAF_ATTR(model_name, CSR_MODEL),
 405         TEXT_LEAF_ATTR(hardware_version_name, CSR_HARDWARE_VERSION),
 406 };
 407
 408 static void init_fw_attribute_group(struct device *dev,
 409                                     struct device_attribute *attrs,
 410                                     struct fw_attribute_group *group)
 411 {
 412         struct device_attribute *attr;
 413         int i, j;
 414
 415         for (j = 0; attrs[j].attr.name != NULL; j++)
 416                 group->attrs[j] = &attrs[j].attr;
 417
 418         for (i = 0; i < ARRAY_SIZE(config_rom_attributes); i++) {
 419                 attr = &config_rom_attributes[i].attr;
 420                 if (attr->show(dev, attr, NULL) < 0)
 421                         continue;
 422                 group->attrs[j++] = &attr->attr;
 423         }
 424
 425         group->attrs[j] = NULL;
 426         group->groups[0] = &group->group;
 427         group->groups[1] = NULL;
 428         group->group.attrs = group->attrs;
 429         dev->groups = (const struct attribute_group **) group->groups;
 430 }
 431
 432 static ssize_t modalias_show(struct device *dev,
 433                              struct device_attribute *attr, char *buf)
 434 {
 435         struct fw_unit *unit = fw_unit(dev);
 436         int length;
 437
 438         length = get_modalias(unit, buf, PAGE_SIZE);
 439         strcpy(buf + length, "\n");
 440
 441         return length + 1;
 442 }
 443
 444 static ssize_t rom_index_show(struct device *dev,
 445                               struct device_attribute *attr, char *buf)
 446 {
 447         struct fw_device *device = fw_device(dev->parent);
 448         struct fw_unit *unit = fw_unit(dev);
 449
 450         return sysfs_emit(buf, "%td\n", unit->directory - device->config_rom);
 451 }
 452
 453 static struct device_attribute fw_unit_attributes[] = {
 454         __ATTR_RO(modalias),
 455         __ATTR_RO(rom_index),
 456         __ATTR_NULL,
 457 };
 458
 459 static ssize_t config_rom_show(struct device *dev,
 460                                struct device_attribute *attr, char *buf)
 461 {
 462         struct fw_device *device = fw_device(dev);
 463         size_t length;
 464
 465         guard(rwsem_read)(&fw_device_rwsem);
 466
 467         length = device->config_rom_length * 4;
 468         memcpy(buf, device->config_rom, length);
 469
 470         return length;
 471 }
 472
 473 static ssize_t guid_show(struct device *dev,
 474                          struct device_attribute *attr, char *buf)
 475 {
 476         struct fw_device *device = fw_device(dev);
 477
 478         guard(rwsem_read)(&fw_device_rwsem);
 479
 480         return sysfs_emit(buf, "0x%08x%08x\n", device->config_rom[3], device->config_rom[4]);
 481 }
 482
 483 static ssize_t is_local_show(struct device *dev,
 484                              struct device_attribute *attr, char *buf)
 485 {
 486         struct fw_device *device = fw_device(dev);
 487
 488         return sysfs_emit(buf, "%u\n", device->is_local);
 489 }
 490
 491 static int units_sprintf(char *buf, const u32 *directory)
 492 {
 493         struct fw_csr_iterator ci;
 494         int key, value;
 495         int specifier_id = 0;
 496         int version = 0;
 497
 498         fw_csr_iterator_init(&ci, directory);
 499         while (fw_csr_iterator_next(&ci, &key, &value)) {
 500                 switch (key) {
 501                 case CSR_SPECIFIER_ID:
 502                         specifier_id = value;
 503                         break;
 504                 case CSR_VERSION:
 505                         version = value;
 506                         break;
 507                 }
 508         }
 509
 510         return sprintf(buf, "0x%06x:0x%06x ", specifier_id, version);
 511 }
 512
 513 static ssize_t units_show(struct device *dev,
 514                           struct device_attribute *attr, char *buf)
 515 {
 516         struct fw_device *device = fw_device(dev);
 517         struct fw_csr_iterator ci;
 518         int key, value, i = 0;
 519
 520         guard(rwsem_read)(&fw_device_rwsem);
 521
 522         fw_csr_iterator_init(&ci, &device->config_rom[ROOT_DIR_OFFSET]);
 523         while (fw_csr_iterator_next(&ci, &key, &value)) {
 524                 if (key != (CSR_UNIT | CSR_DIRECTORY))
 525                         continue;
 526                 i += units_sprintf(&buf[i], ci.p + value - 1);
 527                 if (i >= PAGE_SIZE - (8 + 1 + 8 + 1))
 528                         break;
 529         }
 530
 531         if (i)
 532                 buf[i - 1] = '\n';
 533
 534         return i;
 535 }
 536
 537 static struct device_attribute fw_device_attributes[] = {
 538         __ATTR_RO(config_rom),
 539         __ATTR_RO(guid),
 540         __ATTR_RO(is_local),
 541         __ATTR_RO(units),
 542         __ATTR_NULL,
 543 };
 544
 545 static int read_rom(struct fw_device *device,
 546                     int generation, int index, u32 *data)
 547 {
 548         u64 offset = (CSR_REGISTER_BASE | CSR_CONFIG_ROM) + index * 4;
 549         int i, rcode;
 550
 551         /* device->node_id, accessed below, must not be older than generation */
 552         smp_rmb();
 553
 554         for (i = 10; i < 100; i += 10) {
 555                 rcode = fw_run_transaction(device->card,
 556                                 TCODE_READ_QUADLET_REQUEST, device->node_id,
 557                                 generation, device->max_speed, offset, data, 4);
 558                 if (rcode != RCODE_BUSY)
 559                         break;
 560                 msleep(i);
 561         }
 562         be32_to_cpus(data);
 563
 564         return rcode;
 565 }
 566
 567 // By quadlet unit.
 568 #define MAX_CONFIG_ROM_SIZE     ((CSR_CONFIG_ROM_END - CSR_CONFIG_ROM) / sizeof(u32))
 569
 570 /*
 571  * Read the bus info block, perform a speed probe, and read all of the rest of
 572  * the config ROM.  We do all this with a cached bus generation.  If the bus
 573  * generation changes under us, read_config_rom will fail and get retried.
 574  * It's better to start all over in this case because the node from which we
 575  * are reading the ROM may have changed the ROM during the reset.
 576  * Returns either a result code or a negative error code.
 577  */
 578 static int read_config_rom(struct fw_device *device, int generation)
 579 {
 580         struct fw_card *card = device->card;
 581         const u32 *old_rom, *new_rom;
 582         u32 *rom, *stack;
 583         u32 sp, key;
 584         int i, end, length, ret;
 585
 586         rom = kmalloc(sizeof(*rom) * MAX_CONFIG_ROM_SIZE +
 587                       sizeof(*stack) * MAX_CONFIG_ROM_SIZE, GFP_KERNEL);
 588         if (rom == NULL)
 589                 return -ENOMEM;
 590
 591         stack = &rom[MAX_CONFIG_ROM_SIZE];
 592         memset(rom, 0, sizeof(*rom) * MAX_CONFIG_ROM_SIZE);
 593
 594         device->max_speed = SCODE_100;
 595
 596         /* First read the bus info block. */
 597         for (i = 0; i < 5; i++) {
 598                 ret = read_rom(device, generation, i, &rom[i]);
 599                 if (ret != RCODE_COMPLETE)
 600                         goto out;
 601                 /*
 602                  * As per IEEE1212 7.2, during initialization, devices can
 603                  * reply with a 0 for the first quadlet of the config
 604                  * rom to indicate that they are booting (for example,
 605                  * if the firmware is on the disk of a external
 606                  * harddisk).  In that case we just fail, and the
 607                  * retry mechanism will try again later.
 608                  */
 609                 if (i == 0 && rom[i] == 0) {
 610                         ret = RCODE_BUSY;
 611                         goto out;
 612                 }
 613         }
 614
 615         device->max_speed = device->node->max_speed;
 616
 617         /*
 618          * Determine the speed of
 619          *   - devices with link speed less than PHY speed,
 620          *   - devices with 1394b PHY (unless only connected to 1394a PHYs),
 621          *   - all devices if there are 1394b repeaters.
 622          * Note, we cannot use the bus info block's link_spd as starting point
 623          * because some buggy firmwares set it lower than necessary and because
 624          * 1394-1995 nodes do not have the field.
 625          */
 626         if ((rom[2] & 0x7) < device->max_speed ||
 627             device->max_speed == SCODE_BETA ||
 628             card->beta_repeaters_present) {
 629                 u32 dummy;
 630
 631                 /* for S1600 and S3200 */
 632                 if (device->max_speed == SCODE_BETA)
 633                         device->max_speed = card->link_speed;
 634
 635                 while (device->max_speed > SCODE_100) {
 636                         if (read_rom(device, generation, 0, &dummy) ==
 637                             RCODE_COMPLETE)
 638                                 break;
 639                         device->max_speed--;
 640                 }
 641         }
 642
 643         /*
 644          * Now parse the config rom.  The config rom is a recursive
 645          * directory structure so we parse it using a stack of
 646          * references to the blocks that make up the structure.  We
 647          * push a reference to the root directory on the stack to
 648          * start things off.
 649          */
 650         length = i;
 651         sp = 0;
 652         stack[sp++] = 0xc0000005;
 653         while (sp > 0) {
 654                 /*
 655                  * Pop the next block reference of the stack.  The
 656                  * lower 24 bits is the offset into the config rom,
 657                  * the upper 8 bits are the type of the reference the
 658                  * block.
 659                  */
 660                 key = stack[--sp];
 661                 i = key & 0xffffff;
 662                 if (WARN_ON(i >= MAX_CONFIG_ROM_SIZE)) {
 663                         ret = -ENXIO;
 664                         goto out;
 665                 }
 666
 667                 /* Read header quadlet for the block to get the length. */
 668                 ret = read_rom(device, generation, i, &rom[i]);
 669                 if (ret != RCODE_COMPLETE)
 670                         goto out;
 671                 end = i + (rom[i] >> 16) + 1;
 672                 if (end > MAX_CONFIG_ROM_SIZE) {
 673                         /*
 674                          * This block extends outside the config ROM which is
 675                          * a firmware bug.  Ignore this whole block, i.e.
 676                          * simply set a fake block length of 0.
 677                          */
 678                         fw_err(card, "skipped invalid ROM block %x at %llx\n",
 679                                rom[i],
 680                                i * 4 | CSR_REGISTER_BASE | CSR_CONFIG_ROM);
 681                         rom[i] = 0;
 682                         end = i;
 683                 }
 684                 i++;
 685
 686                 /*
 687                  * Now read in the block.  If this is a directory
 688                  * block, check the entries as we read them to see if
 689                  * it references another block, and push it in that case.
 690                  */
 691                 for (; i < end; i++) {
 692                         ret = read_rom(device, generation, i, &rom[i]);
 693                         if (ret != RCODE_COMPLETE)
 694                                 goto out;
 695
 696                         if ((key >> 30) != 3 || (rom[i] >> 30) < 2)
 697                                 continue;
 698                         /*
 699                          * Offset points outside the ROM.  May be a firmware
 700                          * bug or an Extended ROM entry (IEEE 1212-2001 clause
 701                          * 7.7.18).  Simply overwrite this pointer here by a
 702                          * fake immediate entry so that later iterators over
 703                          * the ROM don't have to check offsets all the time.
 704                          */
 705                         if (i + (rom[i] & 0xffffff) >= MAX_CONFIG_ROM_SIZE) {
 706                                 fw_err(card,
 707                                        "skipped unsupported ROM entry %x at %llx\n",
 708                                        rom[i],
 709                                        i * 4 | CSR_REGISTER_BASE | CSR_CONFIG_ROM);
 710                                 rom[i] = 0;
 711                                 continue;
 712                         }
 713                         stack[sp++] = i + rom[i];
 714                 }
 715                 if (length < i)
 716                         length = i;
 717         }
 718
 719         old_rom = device->config_rom;
 720         new_rom = kmemdup(rom, length * 4, GFP_KERNEL);
 721         if (new_rom == NULL) {
 722                 ret = -ENOMEM;
 723                 goto out;
 724         }
 725
 726         scoped_guard(rwsem_write, &fw_device_rwsem) {
 727                 device->config_rom = new_rom;
 728                 device->config_rom_length = length;
 729         }
 730
 731         kfree(old_rom);
 732         ret = RCODE_COMPLETE;
 733         device->max_rec = rom[2] >> 12 & 0xf;
 734         device->cmc     = rom[2] >> 30 & 1;
 735         device->irmc    = rom[2] >> 31 & 1;
 736  out:
 737         kfree(rom);
 738
 739         return ret;
 740 }
 741
 742 static void fw_unit_release(struct device *dev)
 743 {
 744         struct fw_unit *unit = fw_unit(dev);
 745
 746         fw_device_put(fw_parent_device(unit));
 747         kfree(unit);
 748 }
 749
 750 static struct device_type fw_unit_type = {
 751         .uevent         = fw_unit_uevent,
 752         .release        = fw_unit_release,
 753 };
 754
 755 static bool is_fw_unit(const struct device *dev)
 756 {
 757         return dev->type == &fw_unit_type;
 758 }
 759
 760 static void create_units(struct fw_device *device)
 761 {
 762         struct fw_csr_iterator ci;
 763         struct fw_unit *unit;
 764         int key, value, i;
 765
 766         i = 0;
 767         fw_csr_iterator_init(&ci, &device->config_rom[ROOT_DIR_OFFSET]);
 768         while (fw_csr_iterator_next(&ci, &key, &value)) {
 769                 if (key != (CSR_UNIT | CSR_DIRECTORY))
 770                         continue;
 771
 772                 /*
 773                  * Get the address of the unit directory and try to
 774                  * match the drivers id_tables against it.
 775                  */
 776                 unit = kzalloc(sizeof(*unit), GFP_KERNEL);
 777                 if (unit == NULL)
 778                         continue;
 779
 780                 unit->directory = ci.p + value - 1;
 781                 unit->device.bus = &fw_bus_type;
 782                 unit->device.type = &fw_unit_type;
 783                 unit->device.parent = &device->device;
 784                 dev_set_name(&unit->device, "%s.%d", dev_name(&device->device), i++);
 785
 786                 BUILD_BUG_ON(ARRAY_SIZE(unit->attribute_group.attrs) <
 787                                 ARRAY_SIZE(fw_unit_attributes) +
 788                                 ARRAY_SIZE(config_rom_attributes));
 789                 init_fw_attribute_group(&unit->device,
 790                                         fw_unit_attributes,
 791                                         &unit->attribute_group);
 792
 793                 fw_device_get(device);
 794                 if (device_register(&unit->device) < 0) {
 795                         put_device(&unit->device);
 796                         continue;
 797                 }
 798         }
 799 }
 800
 801 static int shutdown_unit(struct device *device, void *data)
 802 {
 803         device_unregister(device);
 804
 805         return 0;
 806 }
 807
 808 /*
 809  * fw_device_rwsem acts as dual purpose mutex:
 810  *   - serializes accesses to fw_device.config_rom/.config_rom_length and
 811  *     fw_unit.directory, unless those accesses happen at safe occasions
 812  */
 813 DECLARE_RWSEM(fw_device_rwsem);
 814
 815 DEFINE_XARRAY_ALLOC(fw_device_xa);
 816 int fw_cdev_major;
 817
 818 struct fw_device *fw_device_get_by_devt(dev_t devt)
 819 {
 820         struct fw_device *device;
 821
 822         device = xa_load(&fw_device_xa, MINOR(devt));
 823         if (device)
 824                 fw_device_get(device);
 825
 826         return device;
 827 }
 828
 829 struct workqueue_struct *fw_workqueue;
 830 EXPORT_SYMBOL(fw_workqueue);
 831
 832 static void fw_schedule_device_work(struct fw_device *device,
 833                                     unsigned long delay)
 834 {
 835         queue_delayed_work(fw_workqueue, &device->work, delay);
 836 }
 837
 838 /*
 839  * These defines control the retry behavior for reading the config
 840  * rom.  It shouldn't be necessary to tweak these; if the device
 841  * doesn't respond to a config rom read within 10 seconds, it's not
 842  * going to respond at all.  As for the initial delay, a lot of
 843  * devices will be able to respond within half a second after bus
 844  * reset.  On the other hand, it's not really worth being more
 845  * aggressive than that, since it scales pretty well; if 10 devices
 846  * are plugged in, they're all getting read within one second.
 847  */
 848
 849 #define MAX_RETRIES     10
 850 #define RETRY_DELAY     (3 * HZ)
 851 #define INITIAL_DELAY   (HZ / 2)
 852 #define SHUTDOWN_DELAY  (2 * HZ)
 853
 854 static void fw_device_shutdown(struct work_struct *work)
 855 {
 856         struct fw_device *device =
 857                 container_of(work, struct fw_device, work.work);
 858
 859         if (time_before64(get_jiffies_64(),
 860                           device->card->reset_jiffies + SHUTDOWN_DELAY)
 861             && !list_empty(&device->card->link)) {
 862                 fw_schedule_device_work(device, SHUTDOWN_DELAY);
 863                 return;
 864         }
 865
 866         if (atomic_cmpxchg(&device->state,
 867                            FW_DEVICE_GONE,
 868                            FW_DEVICE_SHUTDOWN) != FW_DEVICE_GONE)
 869                 return;
 870
 871         fw_device_cdev_remove(device);
 872         device_for_each_child(&device->device, NULL, shutdown_unit);
 873         device_unregister(&device->device);
 874
 875         xa_erase(&fw_device_xa, MINOR(device->device.devt));
 876
 877         fw_device_put(device);
 878 }
 879
 880 static void fw_device_release(struct device *dev)
 881 {
 882         struct fw_device *device = fw_device(dev);
 883         struct fw_card *card = device->card;
 884
 885         /*
 886          * Take the card lock so we don't set this to NULL while a
 887          * FW_NODE_UPDATED callback is being handled or while the
 888          * bus manager work looks at this node.
 889          */
 890         scoped_guard(spinlock_irqsave, &card->lock)
 891                 device->node->data = NULL;
 892
 893         fw_node_put(device->node);
 894         kfree(device->config_rom);
 895         kfree(device);
 896         fw_card_put(card);
 897 }
 898
 899 static struct device_type fw_device_type = {
 900         .release = fw_device_release,
 901 };
 902
 903 static bool is_fw_device(const struct device *dev)
 904 {
 905         return dev->type == &fw_device_type;
 906 }
 907
 908 static int update_unit(struct device *dev, void *data)
 909 {
 910         struct fw_unit *unit = fw_unit(dev);
 911         struct fw_driver *driver = (struct fw_driver *)dev->driver;
 912
 913         if (is_fw_unit(dev) && driver != NULL && driver->update != NULL) {
 914                 device_lock(dev);
 915                 driver->update(unit);
 916                 device_unlock(dev);
 917         }
 918
 919         return 0;
 920 }
 921
 922 static void fw_device_update(struct work_struct *work)
 923 {
 924         struct fw_device *device =
 925                 container_of(work, struct fw_device, work.work);
 926
 927         fw_device_cdev_update(device);
 928         device_for_each_child(&device->device, NULL, update_unit);
 929 }
 930
 931 enum { BC_UNKNOWN = 0, BC_UNIMPLEMENTED, BC_IMPLEMENTED, };
 932
 933 static void set_broadcast_channel(struct fw_device *device, int generation)
 934 {
 935         struct fw_card *card = device->card;
 936         __be32 data;
 937         int rcode;
 938
 939         if (!card->broadcast_channel_allocated)
 940                 return;
 941
 942         /*
 943          * The Broadcast_Channel Valid bit is required by nodes which want to
 944          * transmit on this channel.  Such transmissions are practically
 945          * exclusive to IP over 1394 (RFC 2734).  IP capable nodes are required
 946          * to be IRM capable and have a max_rec of 8 or more.  We use this fact
 947          * to narrow down to which nodes we send Broadcast_Channel updates.
 948          */
 949         if (!device->irmc || device->max_rec < 8)
 950                 return;
 951
 952         /*
 953          * Some 1394-1995 nodes crash if this 1394a-2000 register is written.
 954          * Perform a read test first.
 955          */
 956         if (device->bc_implemented == BC_UNKNOWN) {
 957                 rcode = fw_run_transaction(card, TCODE_READ_QUADLET_REQUEST,
 958                                 device->node_id, generation, device->max_speed,
 959                                 CSR_REGISTER_BASE + CSR_BROADCAST_CHANNEL,
 960                                 &data, 4);
 961                 switch (rcode) {
 962                 case RCODE_COMPLETE:
 963                         if (data & cpu_to_be32(1 << 31)) {
 964                                 device->bc_implemented = BC_IMPLEMENTED;
 965                                 break;
 966                         }
 967                         fallthrough;    /* to case address error */
 968                 case RCODE_ADDRESS_ERROR:
 969                         device->bc_implemented = BC_UNIMPLEMENTED;
 970                 }
 971         }
 972
 973         if (device->bc_implemented == BC_IMPLEMENTED) {
 974                 data = cpu_to_be32(BROADCAST_CHANNEL_INITIAL |
 975                                    BROADCAST_CHANNEL_VALID);
 976                 fw_run_transaction(card, TCODE_WRITE_QUADLET_REQUEST,
 977                                 device->node_id, generation, device->max_speed,
 978                                 CSR_REGISTER_BASE + CSR_BROADCAST_CHANNEL,
 979                                 &data, 4);
 980         }
 981 }
 982
 983 int fw_device_set_broadcast_channel(struct device *dev, void *gen)
 984 {
 985         if (is_fw_device(dev))
 986                 set_broadcast_channel(fw_device(dev), (long)gen);
 987
 988         return 0;
 989 }
 990
 991 static int compare_configuration_rom(struct device *dev, void *data)
 992 {
 993         const struct fw_device *old = fw_device(dev);
 994         const u32 *config_rom = data;
 995
 996         if (!is_fw_device(dev))
 997                 return 0;
 998
 999         // Compare the bus information block and root_length/root_crc.
1000         return !memcmp(old->config_rom, config_rom, 6 * 4);
1001 }
1002
1003 static void fw_device_init(struct work_struct *work)
1004 {
1005         struct fw_device *device =
1006                 container_of(work, struct fw_device, work.work);
1007         struct fw_card *card = device->card;
1008         struct device *found;
1009         u32 minor;
1010         int ret;
1011
1012         /*
1013          * All failure paths here set node->data to NULL, so that we
1014          * don't try to do device_for_each_child() on a kfree()'d
1015          * device.
1016          */
1017
1018         ret = read_config_rom(device, device->generation);
1019         if (ret != RCODE_COMPLETE) {
1020                 if (device->config_rom_retries < MAX_RETRIES &&
1021                     atomic_read(&device->state) == FW_DEVICE_INITIALIZING) {
1022                         device->config_rom_retries++;
1023                         fw_schedule_device_work(device, RETRY_DELAY);
1024                 } else {
1025                         if (device->node->link_on)
1026                                 fw_notice(card, "giving up on node %x: reading config rom failed: %s\n",
1027                                           device->node_id,
1028                                           fw_rcode_string(ret));
1029                         if (device->node == card->root_node)
1030                                 fw_schedule_bm_work(card, 0);
1031                         fw_device_release(&device->device);
1032                 }
1033                 return;
1034         }
1035
1036         // If a device was pending for deletion because its node went away but its bus info block
1037         // and root directory header matches that of a newly discovered device, revive the
1038         // existing fw_device. The newly allocated fw_device becomes obsolete instead.
1039         //
1040         // serialize config_rom access.
1041         scoped_guard(rwsem_read, &fw_device_rwsem) {
1042                 found = device_find_child(card->device, (void *)device->config_rom,
1043                                           compare_configuration_rom);
1044         }
1045         if (found) {
1046                 struct fw_device *reused = fw_device(found);
1047
1048                 if (atomic_cmpxchg(&reused->state,
1049                                    FW_DEVICE_GONE,
1050                                    FW_DEVICE_RUNNING) == FW_DEVICE_GONE) {
1051                         // serialize node access
1052                         scoped_guard(spinlock_irq, &card->lock) {
1053                                 struct fw_node *current_node = device->node;
1054                                 struct fw_node *obsolete_node = reused->node;
1055
1056                                 device->node = obsolete_node;
1057                                 device->node->data = device;
1058                                 reused->node = current_node;
1059                                 reused->node->data = reused;
1060
1061                                 reused->max_speed = device->max_speed;
1062                                 reused->node_id = current_node->node_id;
1063                                 smp_wmb();  /* update node_id before generation */
1064                                 reused->generation = card->generation;
1065                                 reused->config_rom_retries = 0;
1066                                 fw_notice(card, "rediscovered device %s\n",
1067                                           dev_name(found));
1068
1069                                 reused->workfn = fw_device_update;
1070                                 fw_schedule_device_work(reused, 0);
1071
1072                                 if (current_node == card->root_node)
1073                                         fw_schedule_bm_work(card, 0);
1074                         }
1075
1076                         put_device(found);
1077                         fw_device_release(&device->device);
1078
1079                         return;
1080                 }
1081
1082                 put_device(found);
1083         }
1084
1085         device_initialize(&device->device);
1086
1087         fw_device_get(device);
1088
1089         // The index of allocated entry is used for minor identifier of device node.
1090         ret = xa_alloc(&fw_device_xa, &minor, device, XA_LIMIT(0, MINORMASK), GFP_KERNEL);
1091         if (ret < 0)
1092                 goto error;
1093
1094         device->device.bus = &fw_bus_type;
1095         device->device.type = &fw_device_type;
1096         device->device.parent = card->device;
1097         device->device.devt = MKDEV(fw_cdev_major, minor);
1098         dev_set_name(&device->device, "fw%d", minor);
1099
1100         BUILD_BUG_ON(ARRAY_SIZE(device->attribute_group.attrs) <
1101                         ARRAY_SIZE(fw_device_attributes) +
1102                         ARRAY_SIZE(config_rom_attributes));
1103         init_fw_attribute_group(&device->device,
1104                                 fw_device_attributes,
1105                                 &device->attribute_group);
1106
1107         if (device_add(&device->device)) {
1108                 fw_err(card, "failed to add device\n");
1109                 goto error_with_cdev;
1110         }
1111
1112         create_units(device);
1113
1114         /*
1115          * Transition the device to running state.  If it got pulled
1116          * out from under us while we did the initialization work, we
1117          * have to shut down the device again here.  Normally, though,
1118          * fw_node_event will be responsible for shutting it down when
1119          * necessary.  We have to use the atomic cmpxchg here to avoid
1120          * racing with the FW_NODE_DESTROYED case in
1121          * fw_node_event().
1122          */
1123         if (atomic_cmpxchg(&device->state,
1124                            FW_DEVICE_INITIALIZING,
1125                            FW_DEVICE_RUNNING) == FW_DEVICE_GONE) {
1126                 device->workfn = fw_device_shutdown;
1127                 fw_schedule_device_work(device, SHUTDOWN_DELAY);
1128         } else {
1129                 fw_notice(card, "created device %s: GUID %08x%08x, S%d00\n",
1130                           dev_name(&device->device),
1131                           device->config_rom[3], device->config_rom[4],
1132                           1 << device->max_speed);
1133                 device->config_rom_retries = 0;
1134
1135                 set_broadcast_channel(device, device->generation);
1136
1137                 add_device_randomness(&device->config_rom[3], 8);
1138         }
1139
1140         /*
1141          * Reschedule the IRM work if we just finished reading the
1142          * root node config rom.  If this races with a bus reset we
1143          * just end up running the IRM work a couple of extra times -
1144          * pretty harmless.
1145          */
1146         if (device->node == card->root_node)
1147                 fw_schedule_bm_work(card, 0);
1148
1149         return;
1150
1151  error_with_cdev:
1152         xa_erase(&fw_device_xa, minor);
1153  error:
1154         fw_device_put(device);          // fw_device_xa's reference.
1155
1156         put_device(&device->device);    /* our reference */
1157 }
1158
1159 /* Reread and compare bus info block and header of root directory */
1160 static int reread_config_rom(struct fw_device *device, int generation,
1161                              bool *changed)
1162 {
1163         u32 q;
1164         int i, rcode;
1165
1166         for (i = 0; i < 6; i++) {
1167                 rcode = read_rom(device, generation, i, &q);
1168                 if (rcode != RCODE_COMPLETE)
1169                         return rcode;
1170
1171                 if (i == 0 && q == 0)
1172                         /* inaccessible (see read_config_rom); retry later */
1173                         return RCODE_BUSY;
1174
1175                 if (q != device->config_rom[i]) {
1176                         *changed = true;
1177                         return RCODE_COMPLETE;
1178                 }
1179         }
1180
1181         *changed = false;
1182         return RCODE_COMPLETE;
1183 }
1184
1185 static void fw_device_refresh(struct work_struct *work)
1186 {
1187         struct fw_device *device =
1188                 container_of(work, struct fw_device, work.work);
1189         struct fw_card *card = device->card;
1190         int ret, node_id = device->node_id;
1191         bool changed;
1192
1193         ret = reread_config_rom(device, device->generation, &changed);
1194         if (ret != RCODE_COMPLETE)
1195                 goto failed_config_rom;
1196
1197         if (!changed) {
1198                 if (atomic_cmpxchg(&device->state,
1199                                    FW_DEVICE_INITIALIZING,
1200                                    FW_DEVICE_RUNNING) == FW_DEVICE_GONE)
1201                         goto gone;
1202
1203                 fw_device_update(work);
1204                 device->config_rom_retries = 0;
1205                 goto out;
1206         }
1207
1208         /*
1209          * Something changed.  We keep things simple and don't investigate
1210          * further.  We just destroy all previous units and create new ones.
1211          */
1212         device_for_each_child(&device->device, NULL, shutdown_unit);
1213
1214         ret = read_config_rom(device, device->generation);
1215         if (ret != RCODE_COMPLETE)
1216                 goto failed_config_rom;
1217
1218         fw_device_cdev_update(device);
1219         create_units(device);
1220
1221         /* Userspace may want to re-read attributes. */
1222         kobject_uevent(&device->device.kobj, KOBJ_CHANGE);
1223
1224         if (atomic_cmpxchg(&device->state,
1225                            FW_DEVICE_INITIALIZING,
1226                            FW_DEVICE_RUNNING) == FW_DEVICE_GONE)
1227                 goto gone;
1228
1229         fw_notice(card, "refreshed device %s\n", dev_name(&device->device));
1230         device->config_rom_retries = 0;
1231         goto out;
1232
1233  failed_config_rom:
1234         if (device->config_rom_retries < MAX_RETRIES &&
1235             atomic_read(&device->state) == FW_DEVICE_INITIALIZING) {
1236                 device->config_rom_retries++;
1237                 fw_schedule_device_work(device, RETRY_DELAY);
1238                 return;
1239         }
1240
1241         fw_notice(card, "giving up on refresh of device %s: %s\n",
1242                   dev_name(&device->device), fw_rcode_string(ret));
1243  gone:
1244         atomic_set(&device->state, FW_DEVICE_GONE);
1245         device->workfn = fw_device_shutdown;
1246         fw_schedule_device_work(device, SHUTDOWN_DELAY);
1247  out:
1248         if (node_id == card->root_node->node_id)
1249                 fw_schedule_bm_work(card, 0);
1250 }
1251
1252 static void fw_device_workfn(struct work_struct *work)
1253 {
1254         struct fw_device *device = container_of(to_delayed_work(work),
1255                                                 struct fw_device, work);
1256         device->workfn(work);
1257 }
1258
1259 void fw_node_event(struct fw_card *card, struct fw_node *node, int event)
1260 {
1261         struct fw_device *device;
1262
1263         switch (event) {
1264         case FW_NODE_CREATED:
1265                 /*
1266                  * Attempt to scan the node, regardless whether its self ID has
1267                  * the L (link active) flag set or not.  Some broken devices
1268                  * send L=0 but have an up-and-running link; others send L=1
1269                  * without actually having a link.
1270                  */
1271  create:
1272                 device = kzalloc(sizeof(*device), GFP_ATOMIC);
1273                 if (device == NULL)
1274                         break;
1275
1276                 /*
1277                  * Do minimal initialization of the device here, the
1278                  * rest will happen in fw_device_init().
1279                  *
1280                  * Attention:  A lot of things, even fw_device_get(),
1281                  * cannot be done before fw_device_init() finished!
1282                  * You can basically just check device->state and
1283                  * schedule work until then, but only while holding
1284                  * card->lock.
1285                  */
1286                 atomic_set(&device->state, FW_DEVICE_INITIALIZING);
1287                 device->card = fw_card_get(card);
1288                 device->node = fw_node_get(node);
1289                 device->node_id = node->node_id;
1290                 device->generation = card->generation;
1291                 device->is_local = node == card->local_node;
1292                 mutex_init(&device->client_list_mutex);
1293                 INIT_LIST_HEAD(&device->client_list);
1294
1295                 /*
1296                  * Set the node data to point back to this device so
1297                  * FW_NODE_UPDATED callbacks can update the node_id
1298                  * and generation for the device.
1299                  */
1300                 node->data = device;
1301
1302                 /*
1303                  * Many devices are slow to respond after bus resets,
1304                  * especially if they are bus powered and go through
1305                  * power-up after getting plugged in.  We schedule the
1306                  * first config rom scan half a second after bus reset.
1307                  */
1308                 device->workfn = fw_device_init;
1309                 INIT_DELAYED_WORK(&device->work, fw_device_workfn);
1310                 fw_schedule_device_work(device, INITIAL_DELAY);
1311                 break;
1312
1313         case FW_NODE_INITIATED_RESET:
1314         case FW_NODE_LINK_ON:
1315                 device = node->data;
1316                 if (device == NULL)
1317                         goto create;
1318
1319                 device->node_id = node->node_id;
1320                 smp_wmb();  /* update node_id before generation */
1321                 device->generation = card->generation;
1322                 if (atomic_cmpxchg(&device->state,
1323                             FW_DEVICE_RUNNING,
1324                             FW_DEVICE_INITIALIZING) == FW_DEVICE_RUNNING) {
1325                         device->workfn = fw_device_refresh;
1326                         fw_schedule_device_work(device,
1327                                 device->is_local ? 0 : INITIAL_DELAY);
1328                 }
1329                 break;
1330
1331         case FW_NODE_UPDATED:
1332                 device = node->data;
1333                 if (device == NULL)
1334                         break;
1335
1336                 device->node_id = node->node_id;
1337                 smp_wmb();  /* update node_id before generation */
1338                 device->generation = card->generation;
1339                 if (atomic_read(&device->state) == FW_DEVICE_RUNNING) {
1340                         device->workfn = fw_device_update;
1341                         fw_schedule_device_work(device, 0);
1342                 }
1343                 break;
1344
1345         case FW_NODE_DESTROYED:
1346         case FW_NODE_LINK_OFF:
1347                 if (!node->data)
1348                         break;
1349
1350                 /*
1351                  * Destroy the device associated with the node.  There
1352                  * are two cases here: either the device is fully
1353                  * initialized (FW_DEVICE_RUNNING) or we're in the
1354                  * process of reading its config rom
1355                  * (FW_DEVICE_INITIALIZING).  If it is fully
1356                  * initialized we can reuse device->work to schedule a
1357                  * full fw_device_shutdown().  If not, there's work
1358                  * scheduled to read it's config rom, and we just put
1359                  * the device in shutdown state to have that code fail
1360                  * to create the device.
1361                  */
1362                 device = node->data;
1363                 if (atomic_xchg(&device->state,
1364                                 FW_DEVICE_GONE) == FW_DEVICE_RUNNING) {
1365                         device->workfn = fw_device_shutdown;
1366                         fw_schedule_device_work(device,
1367                                 list_empty(&card->link) ? 0 : SHUTDOWN_DELAY);
1368                 }
1369                 break;
1370         }
1371 }
1372
1373 #ifdef CONFIG_FIREWIRE_KUNIT_DEVICE_ATTRIBUTE_TEST
1374 #include "device-attribute-test.c"
1375 #endif