drivers/firewire/core-transaction.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Core IEEE1394 transaction logic
   4  *
   5  * Copyright (C) 2004-2006 Kristian Hoegsberg <krh@bitplanet.net>
   6  */
   7
   8 #include <linux/bug.h>
   9 #include <linux/completion.h>
  10 #include <linux/device.h>
  11 #include <linux/errno.h>
  12 #include <linux/firewire.h>
  13 #include <linux/firewire-constants.h>
  14 #include <linux/fs.h>
  15 #include <linux/init.h>
  16 #include <linux/idr.h>
  17 #include <linux/jiffies.h>
  18 #include <linux/kernel.h>
  19 #include <linux/list.h>
  20 #include <linux/module.h>
  21 #include <linux/rculist.h>
  22 #include <linux/slab.h>
  23 #include <linux/spinlock.h>
  24 #include <linux/string.h>
  25 #include <linux/timer.h>
  26 #include <linux/types.h>
  27 #include <linux/workqueue.h>
  28
  29 #include <asm/byteorder.h>
  30
  31 #include "core.h"
  32
  33 #define HEADER_PRI(pri)                 ((pri) << 0)
  34 #define HEADER_TCODE(tcode)             ((tcode) << 4)
  35 #define HEADER_RETRY(retry)             ((retry) << 8)
  36 #define HEADER_TLABEL(tlabel)           ((tlabel) << 10)
  37 #define HEADER_DESTINATION(destination) ((destination) << 16)
  38 #define HEADER_SOURCE(source)           ((source) << 16)
  39 #define HEADER_RCODE(rcode)             ((rcode) << 12)
  40 #define HEADER_OFFSET_HIGH(offset_high) ((offset_high) << 0)
  41 #define HEADER_DATA_LENGTH(length)      ((length) << 16)
  42 #define HEADER_EXTENDED_TCODE(tcode)    ((tcode) << 0)
  43
  44 #define HEADER_GET_TCODE(q)             (((q) >> 4) & 0x0f)
  45 #define HEADER_GET_TLABEL(q)            (((q) >> 10) & 0x3f)
  46 #define HEADER_GET_RCODE(q)             (((q) >> 12) & 0x0f)
  47 #define HEADER_GET_DESTINATION(q)       (((q) >> 16) & 0xffff)
  48 #define HEADER_GET_SOURCE(q)            (((q) >> 16) & 0xffff)
  49 #define HEADER_GET_OFFSET_HIGH(q)       (((q) >> 0) & 0xffff)
  50 #define HEADER_GET_DATA_LENGTH(q)       (((q) >> 16) & 0xffff)
  51 #define HEADER_GET_EXTENDED_TCODE(q)    (((q) >> 0) & 0xffff)
  52
  53 #define HEADER_DESTINATION_IS_BROADCAST(q) \
  54         (((q) & HEADER_DESTINATION(0x3f)) == HEADER_DESTINATION(0x3f))
  55
  56 #define PHY_PACKET_CONFIG       0x0
  57 #define PHY_PACKET_LINK_ON      0x1
  58 #define PHY_PACKET_SELF_ID      0x2
  59
  60 #define PHY_CONFIG_GAP_COUNT(gap_count) (((gap_count) << 16) | (1 << 22))
  61 #define PHY_CONFIG_ROOT_ID(node_id)     ((((node_id) & 0x3f) << 24) | (1 << 23))
  62 #define PHY_IDENTIFIER(id)              ((id) << 30)
  63
  64 /* returns 0 if the split timeout handler is already running */
  65 static int try_cancel_split_timeout(struct fw_transaction *t)
  66 {
  67         if (t->is_split_transaction)
  68                 return del_timer(&t->split_timeout_timer);
  69         else
  70                 return 1;
  71 }
  72
  73 static int close_transaction(struct fw_transaction *transaction,
  74                              struct fw_card *card, int rcode)
  75 {
  76         struct fw_transaction *t = NULL, *iter;
  77         unsigned long flags;
  78
  79         spin_lock_irqsave(&card->lock, flags);
  80         list_for_each_entry(iter, &card->transaction_list, link) {
  81                 if (iter == transaction) {
  82                         if (!try_cancel_split_timeout(iter)) {
  83                                 spin_unlock_irqrestore(&card->lock, flags);
  84                                 goto timed_out;
  85                         }
  86                         list_del_init(&iter->link);
  87                         card->tlabel_mask &= ~(1ULL << iter->tlabel);
  88                         t = iter;
  89                         break;
  90                 }
  91         }
  92         spin_unlock_irqrestore(&card->lock, flags);
  93
  94         if (t) {
  95                 t->callback(card, rcode, NULL, 0, t->callback_data);
  96                 return 0;
  97         }
  98
  99  timed_out:
 100         return -ENOENT;
 101 }
 102
 103 /*
 104  * Only valid for transactions that are potentially pending (ie have
 105  * been sent).
 106  */
 107 int fw_cancel_transaction(struct fw_card *card,
 108                           struct fw_transaction *transaction)
 109 {
 110         /*
 111          * Cancel the packet transmission if it's still queued.  That
 112          * will call the packet transmission callback which cancels
 113          * the transaction.
 114          */
 115
 116         if (card->driver->cancel_packet(card, &transaction->packet) == 0)
 117                 return 0;
 118
 119         /*
 120          * If the request packet has already been sent, we need to see
 121          * if the transaction is still pending and remove it in that case.
 122          */
 123
 124         return close_transaction(transaction, card, RCODE_CANCELLED);
 125 }
 126 EXPORT_SYMBOL(fw_cancel_transaction);
 127
 128 static void split_transaction_timeout_callback(struct timer_list *timer)
 129 {
 130         struct fw_transaction *t = from_timer(t, timer, split_timeout_timer);
 131         struct fw_card *card = t->card;
 132         unsigned long flags;
 133
 134         spin_lock_irqsave(&card->lock, flags);
 135         if (list_empty(&t->link)) {
 136                 spin_unlock_irqrestore(&card->lock, flags);
 137                 return;
 138         }
 139         list_del(&t->link);
 140         card->tlabel_mask &= ~(1ULL << t->tlabel);
 141         spin_unlock_irqrestore(&card->lock, flags);
 142
 143         t->callback(card, RCODE_CANCELLED, NULL, 0, t->callback_data);
 144 }
 145
 146 static void start_split_transaction_timeout(struct fw_transaction *t,
 147                                             struct fw_card *card)
 148 {
 149         unsigned long flags;
 150
 151         spin_lock_irqsave(&card->lock, flags);
 152
 153         if (list_empty(&t->link) || WARN_ON(t->is_split_transaction)) {
 154                 spin_unlock_irqrestore(&card->lock, flags);
 155                 return;
 156         }
 157
 158         t->is_split_transaction = true;
 159         mod_timer(&t->split_timeout_timer,
 160                   jiffies + card->split_timeout_jiffies);
 161
 162         spin_unlock_irqrestore(&card->lock, flags);
 163 }
 164
 165 static void transmit_complete_callback(struct fw_packet *packet,
 166                                        struct fw_card *card, int status)
 167 {
 168         struct fw_transaction *t =
 169             container_of(packet, struct fw_transaction, packet);
 170
 171         switch (status) {
 172         case ACK_COMPLETE:
 173                 close_transaction(t, card, RCODE_COMPLETE);
 174                 break;
 175         case ACK_PENDING:
 176                 start_split_transaction_timeout(t, card);
 177                 break;
 178         case ACK_BUSY_X:
 179         case ACK_BUSY_A:
 180         case ACK_BUSY_B:
 181                 close_transaction(t, card, RCODE_BUSY);
 182                 break;
 183         case ACK_DATA_ERROR:
 184                 close_transaction(t, card, RCODE_DATA_ERROR);
 185                 break;
 186         case ACK_TYPE_ERROR:
 187                 close_transaction(t, card, RCODE_TYPE_ERROR);
 188                 break;
 189         default:
 190                 /*
 191                  * In this case the ack is really a juju specific
 192                  * rcode, so just forward that to the callback.
 193                  */
 194                 close_transaction(t, card, status);
 195                 break;
 196         }
 197 }
 198
 199 static void fw_fill_request(struct fw_packet *packet, int tcode, int tlabel,
 200                 int destination_id, int source_id, int generation, int speed,
 201                 unsigned long long offset, void *payload, size_t length)
 202 {
 203         int ext_tcode;
 204
 205         if (tcode == TCODE_STREAM_DATA) {
 206                 packet->header[0] =
 207                         HEADER_DATA_LENGTH(length) |
 208                         destination_id |
 209                         HEADER_TCODE(TCODE_STREAM_DATA);
 210                 packet->header_length = 4;
 211                 packet->payload = payload;
 212                 packet->payload_length = length;
 213
 214                 goto common;
 215         }
 216
 217         if (tcode > 0x10) {
 218                 ext_tcode = tcode & ~0x10;
 219                 tcode = TCODE_LOCK_REQUEST;
 220         } else
 221                 ext_tcode = 0;
 222
 223         packet->header[0] =
 224                 HEADER_RETRY(RETRY_X) |
 225                 HEADER_TLABEL(tlabel) |
 226                 HEADER_TCODE(tcode) |
 227                 HEADER_DESTINATION(destination_id);
 228         packet->header[1] =
 229                 HEADER_OFFSET_HIGH(offset >> 32) | HEADER_SOURCE(source_id);
 230         packet->header[2] =
 231                 offset;
 232
 233         switch (tcode) {
 234         case TCODE_WRITE_QUADLET_REQUEST:
 235                 packet->header[3] = *(u32 *)payload;
 236                 packet->header_length = 16;
 237                 packet->payload_length = 0;
 238                 break;
 239
 240         case TCODE_LOCK_REQUEST:
 241         case TCODE_WRITE_BLOCK_REQUEST:
 242                 packet->header[3] =
 243                         HEADER_DATA_LENGTH(length) |
 244                         HEADER_EXTENDED_TCODE(ext_tcode);
 245                 packet->header_length = 16;
 246                 packet->payload = payload;
 247                 packet->payload_length = length;
 248                 break;
 249
 250         case TCODE_READ_QUADLET_REQUEST:
 251                 packet->header_length = 12;
 252                 packet->payload_length = 0;
 253                 break;
 254
 255         case TCODE_READ_BLOCK_REQUEST:
 256                 packet->header[3] =
 257                         HEADER_DATA_LENGTH(length) |
 258                         HEADER_EXTENDED_TCODE(ext_tcode);
 259                 packet->header_length = 16;
 260                 packet->payload_length = 0;
 261                 break;
 262
 263         default:
 264                 WARN(1, "wrong tcode %d\n", tcode);
 265         }
 266  common:
 267         packet->speed = speed;
 268         packet->generation = generation;
 269         packet->ack = 0;
 270         packet->payload_mapped = false;
 271 }
 272
 273 static int allocate_tlabel(struct fw_card *card)
 274 {
 275         int tlabel;
 276
 277         tlabel = card->current_tlabel;
 278         while (card->tlabel_mask & (1ULL << tlabel)) {
 279                 tlabel = (tlabel + 1) & 0x3f;
 280                 if (tlabel == card->current_tlabel)
 281                         return -EBUSY;
 282         }
 283
 284         card->current_tlabel = (tlabel + 1) & 0x3f;
 285         card->tlabel_mask |= 1ULL << tlabel;
 286
 287         return tlabel;
 288 }
 289
 290 /**
 291  * fw_send_request() - submit a request packet for transmission
 292  * @card:               interface to send the request at
 293  * @t:                  transaction instance to which the request belongs
 294  * @tcode:              transaction code
 295  * @destination_id:     destination node ID, consisting of bus_ID and phy_ID
 296  * @generation:         bus generation in which request and response are valid
 297  * @speed:              transmission speed
 298  * @offset:             48bit wide offset into destination's address space
 299  * @payload:            data payload for the request subaction
 300  * @length:             length of the payload, in bytes
 301  * @callback:           function to be called when the transaction is completed
 302  * @callback_data:      data to be passed to the transaction completion callback
 303  *
 304  * Submit a request packet into the asynchronous request transmission queue.
 305  * Can be called from atomic context.  If you prefer a blocking API, use
 306  * fw_run_transaction() in a context that can sleep.
 307  *
 308  * In case of lock requests, specify one of the firewire-core specific %TCODE_
 309  * constants instead of %TCODE_LOCK_REQUEST in @tcode.
 310  *
 311  * Make sure that the value in @destination_id is not older than the one in
 312  * @generation.  Otherwise the request is in danger to be sent to a wrong node.
 313  *
 314  * In case of asynchronous stream packets i.e. %TCODE_STREAM_DATA, the caller
 315  * needs to synthesize @destination_id with fw_stream_packet_destination_id().
 316  * It will contain tag, channel, and sy data instead of a node ID then.
 317  *
 318  * The payload buffer at @data is going to be DMA-mapped except in case of
 319  * @length <= 8 or of local (loopback) requests.  Hence make sure that the
 320  * buffer complies with the restrictions of the streaming DMA mapping API.
 321  * @payload must not be freed before the @callback is called.
 322  *
 323  * In case of request types without payload, @data is NULL and @length is 0.
 324  *
 325  * After the transaction is completed successfully or unsuccessfully, the
 326  * @callback will be called.  Among its parameters is the response code which
 327  * is either one of the rcodes per IEEE 1394 or, in case of internal errors,
 328  * the firewire-core specific %RCODE_SEND_ERROR.  The other firewire-core
 329  * specific rcodes (%RCODE_CANCELLED, %RCODE_BUSY, %RCODE_GENERATION,
 330  * %RCODE_NO_ACK) denote transaction timeout, busy responder, stale request
 331  * generation, or missing ACK respectively.
 332  *
 333  * Note some timing corner cases:  fw_send_request() may complete much earlier
 334  * than when the request packet actually hits the wire.  On the other hand,
 335  * transaction completion and hence execution of @callback may happen even
 336  * before fw_send_request() returns.
 337  */
 338 void fw_send_request(struct fw_card *card, struct fw_transaction *t, int tcode,
 339                      int destination_id, int generation, int speed,
 340                      unsigned long long offset, void *payload, size_t length,
 341                      fw_transaction_callback_t callback, void *callback_data)
 342 {
 343         unsigned long flags;
 344         int tlabel;
 345
 346         /*
 347          * Allocate tlabel from the bitmap and put the transaction on
 348          * the list while holding the card spinlock.
 349          */
 350
 351         spin_lock_irqsave(&card->lock, flags);
 352
 353         tlabel = allocate_tlabel(card);
 354         if (tlabel < 0) {
 355                 spin_unlock_irqrestore(&card->lock, flags);
 356                 callback(card, RCODE_SEND_ERROR, NULL, 0, callback_data);
 357                 return;
 358         }
 359
 360         t->node_id = destination_id;
 361         t->tlabel = tlabel;
 362         t->card = card;
 363         t->is_split_transaction = false;
 364         timer_setup(&t->split_timeout_timer,
 365                     split_transaction_timeout_callback, 0);
 366         t->callback = callback;
 367         t->callback_data = callback_data;
 368
 369         fw_fill_request(&t->packet, tcode, t->tlabel,
 370                         destination_id, card->node_id, generation,
 371                         speed, offset, payload, length);
 372         t->packet.callback = transmit_complete_callback;
 373
 374         list_add_tail(&t->link, &card->transaction_list);
 375
 376         spin_unlock_irqrestore(&card->lock, flags);
 377
 378         card->driver->send_request(card, &t->packet);
 379 }
 380 EXPORT_SYMBOL(fw_send_request);
 381
 382 struct transaction_callback_data {
 383         struct completion done;
 384         void *payload;
 385         int rcode;
 386 };
 387
 388 static void transaction_callback(struct fw_card *card, int rcode,
 389                                  void *payload, size_t length, void *data)
 390 {
 391         struct transaction_callback_data *d = data;
 392
 393         if (rcode == RCODE_COMPLETE)
 394                 memcpy(d->payload, payload, length);
 395         d->rcode = rcode;
 396         complete(&d->done);
 397 }
 398
 399 /**
 400  * fw_run_transaction() - send request and sleep until transaction is completed
 401  * @card:               card interface for this request
 402  * @tcode:              transaction code
 403  * @destination_id:     destination node ID, consisting of bus_ID and phy_ID
 404  * @generation:         bus generation in which request and response are valid
 405  * @speed:              transmission speed
 406  * @offset:             48bit wide offset into destination's address space
 407  * @payload:            data payload for the request subaction
 408  * @length:             length of the payload, in bytes
 409  *
 410  * Returns the RCODE.  See fw_send_request() for parameter documentation.
 411  * Unlike fw_send_request(), @data points to the payload of the request or/and
 412  * to the payload of the response.  DMA mapping restrictions apply to outbound
 413  * request payloads of >= 8 bytes but not to inbound response payloads.
 414  */
 415 int fw_run_transaction(struct fw_card *card, int tcode, int destination_id,
 416                        int generation, int speed, unsigned long long offset,
 417                        void *payload, size_t length)
 418 {
 419         struct transaction_callback_data d;
 420         struct fw_transaction t;
 421
 422         timer_setup_on_stack(&t.split_timeout_timer, NULL, 0);
 423         init_completion(&d.done);
 424         d.payload = payload;
 425         fw_send_request(card, &t, tcode, destination_id, generation, speed,
 426                         offset, payload, length, transaction_callback, &d);
 427         wait_for_completion(&d.done);
 428         destroy_timer_on_stack(&t.split_timeout_timer);
 429
 430         return d.rcode;
 431 }
 432 EXPORT_SYMBOL(fw_run_transaction);
 433
 434 static DEFINE_MUTEX(phy_config_mutex);
 435 static DECLARE_COMPLETION(phy_config_done);
 436
 437 static void transmit_phy_packet_callback(struct fw_packet *packet,
 438                                          struct fw_card *card, int status)
 439 {
 440         complete(&phy_config_done);
 441 }
 442
 443 static struct fw_packet phy_config_packet = {
 444         .header_length  = 12,
 445         .header[0]      = TCODE_LINK_INTERNAL << 4,
 446         .payload_length = 0,
 447         .speed          = SCODE_100,
 448         .callback       = transmit_phy_packet_callback,
 449 };
 450
 451 void fw_send_phy_config(struct fw_card *card,
 452                         int node_id, int generation, int gap_count)
 453 {
 454         long timeout = DIV_ROUND_UP(HZ, 10);
 455         u32 data = PHY_IDENTIFIER(PHY_PACKET_CONFIG);
 456
 457         if (node_id != FW_PHY_CONFIG_NO_NODE_ID)
 458                 data |= PHY_CONFIG_ROOT_ID(node_id);
 459
 460         if (gap_count == FW_PHY_CONFIG_CURRENT_GAP_COUNT) {
 461                 gap_count = card->driver->read_phy_reg(card, 1);
 462                 if (gap_count < 0)
 463                         return;
 464
 465                 gap_count &= 63;
 466                 if (gap_count == 63)
 467                         return;
 468         }
 469         data |= PHY_CONFIG_GAP_COUNT(gap_count);
 470
 471         mutex_lock(&phy_config_mutex);
 472
 473         phy_config_packet.header[1] = data;
 474         phy_config_packet.header[2] = ~data;
 475         phy_config_packet.generation = generation;
 476         reinit_completion(&phy_config_done);
 477
 478         card->driver->send_request(card, &phy_config_packet);
 479         wait_for_completion_timeout(&phy_config_done, timeout);
 480
 481         mutex_unlock(&phy_config_mutex);
 482 }
 483
 484 static struct fw_address_handler *lookup_overlapping_address_handler(
 485         struct list_head *list, unsigned long long offset, size_t length)
 486 {
 487         struct fw_address_handler *handler;
 488
 489         list_for_each_entry_rcu(handler, list, link) {
 490                 if (handler->offset < offset + length &&
 491                     offset < handler->offset + handler->length)
 492                         return handler;
 493         }
 494
 495         return NULL;
 496 }
 497
 498 static bool is_enclosing_handler(struct fw_address_handler *handler,
 499                                  unsigned long long offset, size_t length)
 500 {
 501         return handler->offset <= offset &&
 502                 offset + length <= handler->offset + handler->length;
 503 }
 504
 505 static struct fw_address_handler *lookup_enclosing_address_handler(
 506         struct list_head *list, unsigned long long offset, size_t length)
 507 {
 508         struct fw_address_handler *handler;
 509
 510         list_for_each_entry_rcu(handler, list, link) {
 511                 if (is_enclosing_handler(handler, offset, length))
 512                         return handler;
 513         }
 514
 515         return NULL;
 516 }
 517
 518 static DEFINE_SPINLOCK(address_handler_list_lock);
 519 static LIST_HEAD(address_handler_list);
 520
 521 const struct fw_address_region fw_high_memory_region =
 522         { .start = FW_MAX_PHYSICAL_RANGE, .end = 0xffffe0000000ULL, };
 523 EXPORT_SYMBOL(fw_high_memory_region);
 524
 525 static const struct fw_address_region low_memory_region =
 526         { .start = 0x000000000000ULL, .end = FW_MAX_PHYSICAL_RANGE, };
 527
 528 #if 0
 529 const struct fw_address_region fw_private_region =
 530         { .start = 0xffffe0000000ULL, .end = 0xfffff0000000ULL,  };
 531 const struct fw_address_region fw_csr_region =
 532         { .start = CSR_REGISTER_BASE,
 533           .end   = CSR_REGISTER_BASE | CSR_CONFIG_ROM_END,  };
 534 const struct fw_address_region fw_unit_space_region =
 535         { .start = 0xfffff0000900ULL, .end = 0x1000000000000ULL, };
 536 #endif  /*  0  */
 537
 538 static bool is_in_fcp_region(u64 offset, size_t length)
 539 {
 540         return offset >= (CSR_REGISTER_BASE | CSR_FCP_COMMAND) &&
 541                 offset + length <= (CSR_REGISTER_BASE | CSR_FCP_END);
 542 }
 543
 544 /**
 545  * fw_core_add_address_handler() - register for incoming requests
 546  * @handler:    callback
 547  * @region:     region in the IEEE 1212 node space address range
 548  *
 549  * region->start, ->end, and handler->length have to be quadlet-aligned.
 550  *
 551  * When a request is received that falls within the specified address range,
 552  * the specified callback is invoked.  The parameters passed to the callback
 553  * give the details of the particular request.
 554  *
 555  * To be called in process context.
 556  * Return value:  0 on success, non-zero otherwise.
 557  *
 558  * The start offset of the handler's address region is determined by
 559  * fw_core_add_address_handler() and is returned in handler->offset.
 560  *
 561  * Address allocations are exclusive, except for the FCP registers.
 562  */
 563 int fw_core_add_address_handler(struct fw_address_handler *handler,
 564                                 const struct fw_address_region *region)
 565 {
 566         struct fw_address_handler *other;
 567         int ret = -EBUSY;
 568
 569         if (region->start & 0xffff000000000003ULL ||
 570             region->start >= region->end ||
 571             region->end   > 0x0001000000000000ULL ||
 572             handler->length & 3 ||
 573             handler->length == 0)
 574                 return -EINVAL;
 575
 576         spin_lock(&address_handler_list_lock);
 577
 578         handler->offset = region->start;
 579         while (handler->offset + handler->length <= region->end) {
 580                 if (is_in_fcp_region(handler->offset, handler->length))
 581                         other = NULL;
 582                 else
 583                         other = lookup_overlapping_address_handler
 584                                         (&address_handler_list,
 585                                          handler->offset, handler->length);
 586                 if (other != NULL) {
 587                         handler->offset += other->length;
 588                 } else {
 589                         list_add_tail_rcu(&handler->link, &address_handler_list);
 590                         ret = 0;
 591                         break;
 592                 }
 593         }
 594
 595         spin_unlock(&address_handler_list_lock);
 596
 597         return ret;
 598 }
 599 EXPORT_SYMBOL(fw_core_add_address_handler);
 600
 601 /**
 602  * fw_core_remove_address_handler() - unregister an address handler
 603  * @handler: callback
 604  *
 605  * To be called in process context.
 606  *
 607  * When fw_core_remove_address_handler() returns, @handler->callback() is
 608  * guaranteed to not run on any CPU anymore.
 609  */
 610 void fw_core_remove_address_handler(struct fw_address_handler *handler)
 611 {
 612         spin_lock(&address_handler_list_lock);
 613         list_del_rcu(&handler->link);
 614         spin_unlock(&address_handler_list_lock);
 615         synchronize_rcu();
 616 }
 617 EXPORT_SYMBOL(fw_core_remove_address_handler);
 618
 619 struct fw_request {
 620         struct fw_packet response;
 621         u32 request_header[4];
 622         int ack;
 623         u32 timestamp;
 624         u32 length;
 625         u32 data[];
 626 };
 627
 628 static void free_response_callback(struct fw_packet *packet,
 629                                    struct fw_card *card, int status)
 630 {
 631         struct fw_request *request;
 632
 633         request = container_of(packet, struct fw_request, response);
 634         kfree(request);
 635 }
 636
 637 int fw_get_response_length(struct fw_request *r)
 638 {
 639         int tcode, ext_tcode, data_length;
 640
 641         tcode = HEADER_GET_TCODE(r->request_header[0]);
 642
 643         switch (tcode) {
 644         case TCODE_WRITE_QUADLET_REQUEST:
 645         case TCODE_WRITE_BLOCK_REQUEST:
 646                 return 0;
 647
 648         case TCODE_READ_QUADLET_REQUEST:
 649                 return 4;
 650
 651         case TCODE_READ_BLOCK_REQUEST:
 652                 data_length = HEADER_GET_DATA_LENGTH(r->request_header[3]);
 653                 return data_length;
 654
 655         case TCODE_LOCK_REQUEST:
 656                 ext_tcode = HEADER_GET_EXTENDED_TCODE(r->request_header[3]);
 657                 data_length = HEADER_GET_DATA_LENGTH(r->request_header[3]);
 658                 switch (ext_tcode) {
 659                 case EXTCODE_FETCH_ADD:
 660                 case EXTCODE_LITTLE_ADD:
 661                         return data_length;
 662                 default:
 663                         return data_length / 2;
 664                 }
 665
 666         default:
 667                 WARN(1, "wrong tcode %d\n", tcode);
 668                 return 0;
 669         }
 670 }
 671
 672 void fw_fill_response(struct fw_packet *response, u32 *request_header,
 673                       int rcode, void *payload, size_t length)
 674 {
 675         int tcode, tlabel, extended_tcode, source, destination;
 676
 677         tcode          = HEADER_GET_TCODE(request_header[0]);
 678         tlabel         = HEADER_GET_TLABEL(request_header[0]);
 679         source         = HEADER_GET_DESTINATION(request_header[0]);
 680         destination    = HEADER_GET_SOURCE(request_header[1]);
 681         extended_tcode = HEADER_GET_EXTENDED_TCODE(request_header[3]);
 682
 683         response->header[0] =
 684                 HEADER_RETRY(RETRY_1) |
 685                 HEADER_TLABEL(tlabel) |
 686                 HEADER_DESTINATION(destination);
 687         response->header[1] =
 688                 HEADER_SOURCE(source) |
 689                 HEADER_RCODE(rcode);
 690         response->header[2] = 0;
 691
 692         switch (tcode) {
 693         case TCODE_WRITE_QUADLET_REQUEST:
 694         case TCODE_WRITE_BLOCK_REQUEST:
 695                 response->header[0] |= HEADER_TCODE(TCODE_WRITE_RESPONSE);
 696                 response->header_length = 12;
 697                 response->payload_length = 0;
 698                 break;
 699
 700         case TCODE_READ_QUADLET_REQUEST:
 701                 response->header[0] |=
 702                         HEADER_TCODE(TCODE_READ_QUADLET_RESPONSE);
 703                 if (payload != NULL)
 704                         response->header[3] = *(u32 *)payload;
 705                 else
 706                         response->header[3] = 0;
 707                 response->header_length = 16;
 708                 response->payload_length = 0;
 709                 break;
 710
 711         case TCODE_READ_BLOCK_REQUEST:
 712         case TCODE_LOCK_REQUEST:
 713                 response->header[0] |= HEADER_TCODE(tcode + 2);
 714                 response->header[3] =
 715                         HEADER_DATA_LENGTH(length) |
 716                         HEADER_EXTENDED_TCODE(extended_tcode);
 717                 response->header_length = 16;
 718                 response->payload = payload;
 719                 response->payload_length = length;
 720                 break;
 721
 722         default:
 723                 WARN(1, "wrong tcode %d\n", tcode);
 724         }
 725
 726         response->payload_mapped = false;
 727 }
 728 EXPORT_SYMBOL(fw_fill_response);
 729
 730 static u32 compute_split_timeout_timestamp(struct fw_card *card,
 731                                            u32 request_timestamp)
 732 {
 733         unsigned int cycles;
 734         u32 timestamp;
 735
 736         cycles = card->split_timeout_cycles;
 737         cycles += request_timestamp & 0x1fff;
 738
 739         timestamp = request_timestamp & ~0x1fff;
 740         timestamp += (cycles / 8000) << 13;
 741         timestamp |= cycles % 8000;
 742
 743         return timestamp;
 744 }
 745
 746 static struct fw_request *allocate_request(struct fw_card *card,
 747                                            struct fw_packet *p)
 748 {
 749         struct fw_request *request;
 750         u32 *data, length;
 751         int request_tcode;
 752
 753         request_tcode = HEADER_GET_TCODE(p->header[0]);
 754         switch (request_tcode) {
 755         case TCODE_WRITE_QUADLET_REQUEST:
 756                 data = &p->header[3];
 757                 length = 4;
 758                 break;
 759
 760         case TCODE_WRITE_BLOCK_REQUEST:
 761         case TCODE_LOCK_REQUEST:
 762                 data = p->payload;
 763                 length = HEADER_GET_DATA_LENGTH(p->header[3]);
 764                 break;
 765
 766         case TCODE_READ_QUADLET_REQUEST:
 767                 data = NULL;
 768                 length = 4;
 769                 break;
 770
 771         case TCODE_READ_BLOCK_REQUEST:
 772                 data = NULL;
 773                 length = HEADER_GET_DATA_LENGTH(p->header[3]);
 774                 break;
 775
 776         default:
 777                 fw_notice(card, "ERROR - corrupt request received - %08x %08x %08x\n",
 778                          p->header[0], p->header[1], p->header[2]);
 779                 return NULL;
 780         }
 781
 782         request = kmalloc(sizeof(*request) + length, GFP_ATOMIC);
 783         if (request == NULL)
 784                 return NULL;
 785
 786         request->response.speed = p->speed;
 787         request->response.timestamp =
 788                         compute_split_timeout_timestamp(card, p->timestamp);
 789         request->response.generation = p->generation;
 790         request->response.ack = 0;
 791         request->response.callback = free_response_callback;
 792         request->ack = p->ack;
 793         request->timestamp = p->timestamp;
 794         request->length = length;
 795         if (data)
 796                 memcpy(request->data, data, length);
 797
 798         memcpy(request->request_header, p->header, sizeof(p->header));
 799
 800         return request;
 801 }
 802
 803 void fw_send_response(struct fw_card *card,
 804                       struct fw_request *request, int rcode)
 805 {
 806         if (WARN_ONCE(!request, "invalid for FCP address handlers"))
 807                 return;
 808
 809         /* unified transaction or broadcast transaction: don't respond */
 810         if (request->ack != ACK_PENDING ||
 811             HEADER_DESTINATION_IS_BROADCAST(request->request_header[0])) {
 812                 kfree(request);
 813                 return;
 814         }
 815
 816         if (rcode == RCODE_COMPLETE)
 817                 fw_fill_response(&request->response, request->request_header,
 818                                  rcode, request->data,
 819                                  fw_get_response_length(request));
 820         else
 821                 fw_fill_response(&request->response, request->request_header,
 822                                  rcode, NULL, 0);
 823
 824         card->driver->send_response(card, &request->response);
 825 }
 826 EXPORT_SYMBOL(fw_send_response);
 827
 828 /**
 829  * fw_get_request_speed() - returns speed at which the @request was received
 830  * @request: firewire request data
 831  */
 832 int fw_get_request_speed(struct fw_request *request)
 833 {
 834         return request->response.speed;
 835 }
 836 EXPORT_SYMBOL(fw_get_request_speed);
 837
 838 /**
 839  * fw_request_get_timestamp: Get timestamp of the request.
 840  * @request: The opaque pointer to request structure.
 841  *
 842  * Get timestamp when 1394 OHCI controller receives the asynchronous request subaction. The
 843  * timestamp consists of the low order 3 bits of second field and the full 13 bits of count
 844  * field of isochronous cycle time register.
 845  *
 846  * Returns: timestamp of the request.
 847  */
 848 u32 fw_request_get_timestamp(const struct fw_request *request)
 849 {
 850         return request->timestamp;
 851 }
 852 EXPORT_SYMBOL_GPL(fw_request_get_timestamp);
 853
 854 static void handle_exclusive_region_request(struct fw_card *card,
 855                                             struct fw_packet *p,
 856                                             struct fw_request *request,
 857                                             unsigned long long offset)
 858 {
 859         struct fw_address_handler *handler;
 860         int tcode, destination, source;
 861
 862         destination = HEADER_GET_DESTINATION(p->header[0]);
 863         source      = HEADER_GET_SOURCE(p->header[1]);
 864         tcode       = HEADER_GET_TCODE(p->header[0]);
 865         if (tcode == TCODE_LOCK_REQUEST)
 866                 tcode = 0x10 + HEADER_GET_EXTENDED_TCODE(p->header[3]);
 867
 868         rcu_read_lock();
 869         handler = lookup_enclosing_address_handler(&address_handler_list,
 870                                                    offset, request->length);
 871         if (handler)
 872                 handler->address_callback(card, request,
 873                                           tcode, destination, source,
 874                                           p->generation, offset,
 875                                           request->data, request->length,
 876                                           handler->callback_data);
 877         rcu_read_unlock();
 878
 879         if (!handler)
 880                 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
 881 }
 882
 883 static void handle_fcp_region_request(struct fw_card *card,
 884                                       struct fw_packet *p,
 885                                       struct fw_request *request,
 886                                       unsigned long long offset)
 887 {
 888         struct fw_address_handler *handler;
 889         int tcode, destination, source;
 890
 891         if ((offset != (CSR_REGISTER_BASE | CSR_FCP_COMMAND) &&
 892              offset != (CSR_REGISTER_BASE | CSR_FCP_RESPONSE)) ||
 893             request->length > 0x200) {
 894                 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
 895
 896                 return;
 897         }
 898
 899         tcode       = HEADER_GET_TCODE(p->header[0]);
 900         destination = HEADER_GET_DESTINATION(p->header[0]);
 901         source      = HEADER_GET_SOURCE(p->header[1]);
 902
 903         if (tcode != TCODE_WRITE_QUADLET_REQUEST &&
 904             tcode != TCODE_WRITE_BLOCK_REQUEST) {
 905                 fw_send_response(card, request, RCODE_TYPE_ERROR);
 906
 907                 return;
 908         }
 909
 910         rcu_read_lock();
 911         list_for_each_entry_rcu(handler, &address_handler_list, link) {
 912                 if (is_enclosing_handler(handler, offset, request->length))
 913                         handler->address_callback(card, NULL, tcode,
 914                                                   destination, source,
 915                                                   p->generation, offset,
 916                                                   request->data,
 917                                                   request->length,
 918                                                   handler->callback_data);
 919         }
 920         rcu_read_unlock();
 921
 922         fw_send_response(card, request, RCODE_COMPLETE);
 923 }
 924
 925 void fw_core_handle_request(struct fw_card *card, struct fw_packet *p)
 926 {
 927         struct fw_request *request;
 928         unsigned long long offset;
 929
 930         if (p->ack != ACK_PENDING && p->ack != ACK_COMPLETE)
 931                 return;
 932
 933         if (TCODE_IS_LINK_INTERNAL(HEADER_GET_TCODE(p->header[0]))) {
 934                 fw_cdev_handle_phy_packet(card, p);
 935                 return;
 936         }
 937
 938         request = allocate_request(card, p);
 939         if (request == NULL) {
 940                 /* FIXME: send statically allocated busy packet. */
 941                 return;
 942         }
 943
 944         offset = ((u64)HEADER_GET_OFFSET_HIGH(p->header[1]) << 32) |
 945                 p->header[2];
 946
 947         if (!is_in_fcp_region(offset, request->length))
 948                 handle_exclusive_region_request(card, p, request, offset);
 949         else
 950                 handle_fcp_region_request(card, p, request, offset);
 951
 952 }
 953 EXPORT_SYMBOL(fw_core_handle_request);
 954
 955 void fw_core_handle_response(struct fw_card *card, struct fw_packet *p)
 956 {
 957         struct fw_transaction *t = NULL, *iter;
 958         unsigned long flags;
 959         u32 *data;
 960         size_t data_length;
 961         int tcode, tlabel, source, rcode;
 962
 963         tcode   = HEADER_GET_TCODE(p->header[0]);
 964         tlabel  = HEADER_GET_TLABEL(p->header[0]);
 965         source  = HEADER_GET_SOURCE(p->header[1]);
 966         rcode   = HEADER_GET_RCODE(p->header[1]);
 967
 968         spin_lock_irqsave(&card->lock, flags);
 969         list_for_each_entry(iter, &card->transaction_list, link) {
 970                 if (iter->node_id == source && iter->tlabel == tlabel) {
 971                         if (!try_cancel_split_timeout(iter)) {
 972                                 spin_unlock_irqrestore(&card->lock, flags);
 973                                 goto timed_out;
 974                         }
 975                         list_del_init(&iter->link);
 976                         card->tlabel_mask &= ~(1ULL << iter->tlabel);
 977                         t = iter;
 978                         break;
 979                 }
 980         }
 981         spin_unlock_irqrestore(&card->lock, flags);
 982
 983         if (!t) {
 984  timed_out:
 985                 fw_notice(card, "unsolicited response (source %x, tlabel %x)\n",
 986                           source, tlabel);
 987                 return;
 988         }
 989
 990         /*
 991          * FIXME: sanity check packet, is length correct, does tcodes
 992          * and addresses match.
 993          */
 994
 995         switch (tcode) {
 996         case TCODE_READ_QUADLET_RESPONSE:
 997                 data = (u32 *) &p->header[3];
 998                 data_length = 4;
 999                 break;
1000
1001         case TCODE_WRITE_RESPONSE:
1002                 data = NULL;
1003                 data_length = 0;
1004                 break;
1005
1006         case TCODE_READ_BLOCK_RESPONSE:
1007         case TCODE_LOCK_RESPONSE:
1008                 data = p->payload;
1009                 data_length = HEADER_GET_DATA_LENGTH(p->header[3]);
1010                 break;
1011
1012         default:
1013                 /* Should never happen, this is just to shut up gcc. */
1014                 data = NULL;
1015                 data_length = 0;
1016                 break;
1017         }
1018
1019         /*
1020          * The response handler may be executed while the request handler
1021          * is still pending.  Cancel the request handler.
1022          */
1023         card->driver->cancel_packet(card, &t->packet);
1024
1025         t->callback(card, rcode, data, data_length, t->callback_data);
1026 }
1027 EXPORT_SYMBOL(fw_core_handle_response);
1028
1029 /**
1030  * fw_rcode_string - convert a firewire result code to an error description
1031  * @rcode: the result code
1032  */
1033 const char *fw_rcode_string(int rcode)
1034 {
1035         static const char *const names[] = {
1036                 [RCODE_COMPLETE]       = "no error",
1037                 [RCODE_CONFLICT_ERROR] = "conflict error",
1038                 [RCODE_DATA_ERROR]     = "data error",
1039                 [RCODE_TYPE_ERROR]     = "type error",
1040                 [RCODE_ADDRESS_ERROR]  = "address error",
1041                 [RCODE_SEND_ERROR]     = "send error",
1042                 [RCODE_CANCELLED]      = "timeout",
1043                 [RCODE_BUSY]           = "busy",
1044                 [RCODE_GENERATION]     = "bus reset",
1045                 [RCODE_NO_ACK]         = "no ack",
1046         };
1047
1048         if ((unsigned int)rcode < ARRAY_SIZE(names) && names[rcode])
1049                 return names[rcode];
1050         else
1051                 return "unknown";
1052 }
1053 EXPORT_SYMBOL(fw_rcode_string);
1054
1055 static const struct fw_address_region topology_map_region =
1056         { .start = CSR_REGISTER_BASE | CSR_TOPOLOGY_MAP,
1057           .end   = CSR_REGISTER_BASE | CSR_TOPOLOGY_MAP_END, };
1058
1059 static void handle_topology_map(struct fw_card *card, struct fw_request *request,
1060                 int tcode, int destination, int source, int generation,
1061                 unsigned long long offset, void *payload, size_t length,
1062                 void *callback_data)
1063 {
1064         int start;
1065
1066         if (!TCODE_IS_READ_REQUEST(tcode)) {
1067                 fw_send_response(card, request, RCODE_TYPE_ERROR);
1068                 return;
1069         }
1070
1071         if ((offset & 3) > 0 || (length & 3) > 0) {
1072                 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
1073                 return;
1074         }
1075
1076         start = (offset - topology_map_region.start) / 4;
1077         memcpy(payload, &card->topology_map[start], length);
1078
1079         fw_send_response(card, request, RCODE_COMPLETE);
1080 }
1081
1082 static struct fw_address_handler topology_map = {
1083         .length                 = 0x400,
1084         .address_callback       = handle_topology_map,
1085 };
1086
1087 static const struct fw_address_region registers_region =
1088         { .start = CSR_REGISTER_BASE,
1089           .end   = CSR_REGISTER_BASE | CSR_CONFIG_ROM, };
1090
1091 static void update_split_timeout(struct fw_card *card)
1092 {
1093         unsigned int cycles;
1094
1095         cycles = card->split_timeout_hi * 8000 + (card->split_timeout_lo >> 19);
1096
1097         /* minimum per IEEE 1394, maximum which doesn't overflow OHCI */
1098         cycles = clamp(cycles, 800u, 3u * 8000u);
1099
1100         card->split_timeout_cycles = cycles;
1101         card->split_timeout_jiffies = DIV_ROUND_UP(cycles * HZ, 8000);
1102 }
1103
1104 static void handle_registers(struct fw_card *card, struct fw_request *request,
1105                 int tcode, int destination, int source, int generation,
1106                 unsigned long long offset, void *payload, size_t length,
1107                 void *callback_data)
1108 {
1109         int reg = offset & ~CSR_REGISTER_BASE;
1110         __be32 *data = payload;
1111         int rcode = RCODE_COMPLETE;
1112         unsigned long flags;
1113
1114         switch (reg) {
1115         case CSR_PRIORITY_BUDGET:
1116                 if (!card->priority_budget_implemented) {
1117                         rcode = RCODE_ADDRESS_ERROR;
1118                         break;
1119                 }
1120                 fallthrough;
1121
1122         case CSR_NODE_IDS:
1123                 /*
1124                  * per IEEE 1394-2008 8.3.22.3, not IEEE 1394.1-2004 3.2.8
1125                  * and 9.6, but interoperable with IEEE 1394.1-2004 bridges
1126                  */
1127                 fallthrough;
1128
1129         case CSR_STATE_CLEAR:
1130         case CSR_STATE_SET:
1131         case CSR_CYCLE_TIME:
1132         case CSR_BUS_TIME:
1133         case CSR_BUSY_TIMEOUT:
1134                 if (tcode == TCODE_READ_QUADLET_REQUEST)
1135                         *data = cpu_to_be32(card->driver->read_csr(card, reg));
1136                 else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1137                         card->driver->write_csr(card, reg, be32_to_cpu(*data));
1138                 else
1139                         rcode = RCODE_TYPE_ERROR;
1140                 break;
1141
1142         case CSR_RESET_START:
1143                 if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1144                         card->driver->write_csr(card, CSR_STATE_CLEAR,
1145                                                 CSR_STATE_BIT_ABDICATE);
1146                 else
1147                         rcode = RCODE_TYPE_ERROR;
1148                 break;
1149
1150         case CSR_SPLIT_TIMEOUT_HI:
1151                 if (tcode == TCODE_READ_QUADLET_REQUEST) {
1152                         *data = cpu_to_be32(card->split_timeout_hi);
1153                 } else if (tcode == TCODE_WRITE_QUADLET_REQUEST) {
1154                         spin_lock_irqsave(&card->lock, flags);
1155                         card->split_timeout_hi = be32_to_cpu(*data) & 7;
1156                         update_split_timeout(card);
1157                         spin_unlock_irqrestore(&card->lock, flags);
1158                 } else {
1159                         rcode = RCODE_TYPE_ERROR;
1160                 }
1161                 break;
1162
1163         case CSR_SPLIT_TIMEOUT_LO:
1164                 if (tcode == TCODE_READ_QUADLET_REQUEST) {
1165                         *data = cpu_to_be32(card->split_timeout_lo);
1166                 } else if (tcode == TCODE_WRITE_QUADLET_REQUEST) {
1167                         spin_lock_irqsave(&card->lock, flags);
1168                         card->split_timeout_lo =
1169                                         be32_to_cpu(*data) & 0xfff80000;
1170                         update_split_timeout(card);
1171                         spin_unlock_irqrestore(&card->lock, flags);
1172                 } else {
1173                         rcode = RCODE_TYPE_ERROR;
1174                 }
1175                 break;
1176
1177         case CSR_MAINT_UTILITY:
1178                 if (tcode == TCODE_READ_QUADLET_REQUEST)
1179                         *data = card->maint_utility_register;
1180                 else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1181                         card->maint_utility_register = *data;
1182                 else
1183                         rcode = RCODE_TYPE_ERROR;
1184                 break;
1185
1186         case CSR_BROADCAST_CHANNEL:
1187                 if (tcode == TCODE_READ_QUADLET_REQUEST)
1188                         *data = cpu_to_be32(card->broadcast_channel);
1189                 else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1190                         card->broadcast_channel =
1191                             (be32_to_cpu(*data) & BROADCAST_CHANNEL_VALID) |
1192                             BROADCAST_CHANNEL_INITIAL;
1193                 else
1194                         rcode = RCODE_TYPE_ERROR;
1195                 break;
1196
1197         case CSR_BUS_MANAGER_ID:
1198         case CSR_BANDWIDTH_AVAILABLE:
1199         case CSR_CHANNELS_AVAILABLE_HI:
1200         case CSR_CHANNELS_AVAILABLE_LO:
1201                 /*
1202                  * FIXME: these are handled by the OHCI hardware and
1203                  * the stack never sees these request. If we add
1204                  * support for a new type of controller that doesn't
1205                  * handle this in hardware we need to deal with these
1206                  * transactions.
1207                  */
1208                 BUG();
1209                 break;
1210
1211         default:
1212                 rcode = RCODE_ADDRESS_ERROR;
1213                 break;
1214         }
1215
1216         fw_send_response(card, request, rcode);
1217 }
1218
1219 static struct fw_address_handler registers = {
1220         .length                 = 0x400,
1221         .address_callback       = handle_registers,
1222 };
1223
1224 static void handle_low_memory(struct fw_card *card, struct fw_request *request,
1225                 int tcode, int destination, int source, int generation,
1226                 unsigned long long offset, void *payload, size_t length,
1227                 void *callback_data)
1228 {
1229         /*
1230          * This catches requests not handled by the physical DMA unit,
1231          * i.e., wrong transaction types or unauthorized source nodes.
1232          */
1233         fw_send_response(card, request, RCODE_TYPE_ERROR);
1234 }
1235
1236 static struct fw_address_handler low_memory = {
1237         .length                 = FW_MAX_PHYSICAL_RANGE,
1238         .address_callback       = handle_low_memory,
1239 };
1240
1241 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1242 MODULE_DESCRIPTION("Core IEEE1394 transaction logic");
1243 MODULE_LICENSE("GPL");
1244
1245 static const u32 vendor_textual_descriptor[] = {
1246         /* textual descriptor leaf () */
1247         0x00060000,
1248         0x00000000,
1249         0x00000000,
1250         0x4c696e75,             /* L i n u */
1251         0x78204669,             /* x   F i */
1252         0x72657769,             /* r e w i */
1253         0x72650000,             /* r e     */
1254 };
1255
1256 static const u32 model_textual_descriptor[] = {
1257         /* model descriptor leaf () */
1258         0x00030000,
1259         0x00000000,
1260         0x00000000,
1261         0x4a756a75,             /* J u j u */
1262 };
1263
1264 static struct fw_descriptor vendor_id_descriptor = {
1265         .length = ARRAY_SIZE(vendor_textual_descriptor),
1266         .immediate = 0x03001f11,
1267         .key = 0x81000000,
1268         .data = vendor_textual_descriptor,
1269 };
1270
1271 static struct fw_descriptor model_id_descriptor = {
1272         .length = ARRAY_SIZE(model_textual_descriptor),
1273         .immediate = 0x17023901,
1274         .key = 0x81000000,
1275         .data = model_textual_descriptor,
1276 };
1277
1278 static int __init fw_core_init(void)
1279 {
1280         int ret;
1281
1282         fw_workqueue = alloc_workqueue("firewire", WQ_MEM_RECLAIM, 0);
1283         if (!fw_workqueue)
1284                 return -ENOMEM;
1285
1286         ret = bus_register(&fw_bus_type);
1287         if (ret < 0) {
1288                 destroy_workqueue(fw_workqueue);
1289                 return ret;
1290         }
1291
1292         fw_cdev_major = register_chrdev(0, "firewire", &fw_device_ops);
1293         if (fw_cdev_major < 0) {
1294                 bus_unregister(&fw_bus_type);
1295                 destroy_workqueue(fw_workqueue);
1296                 return fw_cdev_major;
1297         }
1298
1299         fw_core_add_address_handler(&topology_map, &topology_map_region);
1300         fw_core_add_address_handler(&registers, &registers_region);
1301         fw_core_add_address_handler(&low_memory, &low_memory_region);
1302         fw_core_add_descriptor(&vendor_id_descriptor);
1303         fw_core_add_descriptor(&model_id_descriptor);
1304
1305         return 0;
1306 }
1307
1308 static void __exit fw_core_cleanup(void)
1309 {
1310         unregister_chrdev(fw_cdev_major, "firewire");
1311         bus_unregister(&fw_bus_type);
1312         destroy_workqueue(fw_workqueue);
1313         idr_destroy(&fw_device_idr);
1314 }
1315
1316 module_init(fw_core_init);
1317 module_exit(fw_core_cleanup);