drivers/firewire/core-transaction.c

   1 /*
   2  * Core IEEE1394 transaction logic
   3  *
   4  * Copyright (C) 2004-2006 Kristian Hoegsberg <krh@bitplanet.net>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software Foundation,
  18  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19  */
  20
  21 #include <linux/bug.h>
  22 #include <linux/completion.h>
  23 #include <linux/device.h>
  24 #include <linux/errno.h>
  25 #include <linux/firewire.h>
  26 #include <linux/firewire-constants.h>
  27 #include <linux/fs.h>
  28 #include <linux/init.h>
  29 #include <linux/idr.h>
  30 #include <linux/jiffies.h>
  31 #include <linux/kernel.h>
  32 #include <linux/list.h>
  33 #include <linux/module.h>
  34 #include <linux/rculist.h>
  35 #include <linux/slab.h>
  36 #include <linux/spinlock.h>
  37 #include <linux/string.h>
  38 #include <linux/timer.h>
  39 #include <linux/types.h>
  40 #include <linux/workqueue.h>
  41
  42 #include <asm/byteorder.h>
  43
  44 #include "core.h"
  45
  46 #define HEADER_PRI(pri)                 ((pri) << 0)
  47 #define HEADER_TCODE(tcode)             ((tcode) << 4)
  48 #define HEADER_RETRY(retry)             ((retry) << 8)
  49 #define HEADER_TLABEL(tlabel)           ((tlabel) << 10)
  50 #define HEADER_DESTINATION(destination) ((destination) << 16)
  51 #define HEADER_SOURCE(source)           ((source) << 16)
  52 #define HEADER_RCODE(rcode)             ((rcode) << 12)
  53 #define HEADER_OFFSET_HIGH(offset_high) ((offset_high) << 0)
  54 #define HEADER_DATA_LENGTH(length)      ((length) << 16)
  55 #define HEADER_EXTENDED_TCODE(tcode)    ((tcode) << 0)
  56
  57 #define HEADER_GET_TCODE(q)             (((q) >> 4) & 0x0f)
  58 #define HEADER_GET_TLABEL(q)            (((q) >> 10) & 0x3f)
  59 #define HEADER_GET_RCODE(q)             (((q) >> 12) & 0x0f)
  60 #define HEADER_GET_DESTINATION(q)       (((q) >> 16) & 0xffff)
  61 #define HEADER_GET_SOURCE(q)            (((q) >> 16) & 0xffff)
  62 #define HEADER_GET_OFFSET_HIGH(q)       (((q) >> 0) & 0xffff)
  63 #define HEADER_GET_DATA_LENGTH(q)       (((q) >> 16) & 0xffff)
  64 #define HEADER_GET_EXTENDED_TCODE(q)    (((q) >> 0) & 0xffff)
  65
  66 #define HEADER_DESTINATION_IS_BROADCAST(q) \
  67         (((q) & HEADER_DESTINATION(0x3f)) == HEADER_DESTINATION(0x3f))
  68
  69 #define PHY_PACKET_CONFIG       0x0
  70 #define PHY_PACKET_LINK_ON      0x1
  71 #define PHY_PACKET_SELF_ID      0x2
  72
  73 #define PHY_CONFIG_GAP_COUNT(gap_count) (((gap_count) << 16) | (1 << 22))
  74 #define PHY_CONFIG_ROOT_ID(node_id)     ((((node_id) & 0x3f) << 24) | (1 << 23))
  75 #define PHY_IDENTIFIER(id)              ((id) << 30)
  76
  77 /* returns 0 if the split timeout handler is already running */
  78 static int try_cancel_split_timeout(struct fw_transaction *t)
  79 {
  80         if (t->is_split_transaction)
  81                 return del_timer(&t->split_timeout_timer);
  82         else
  83                 return 1;
  84 }
  85
  86 static int close_transaction(struct fw_transaction *transaction,
  87                              struct fw_card *card, int rcode)
  88 {
  89         struct fw_transaction *t;
  90         unsigned long flags;
  91
  92         spin_lock_irqsave(&card->lock, flags);
  93         list_for_each_entry(t, &card->transaction_list, link) {
  94                 if (t == transaction) {
  95                         if (!try_cancel_split_timeout(t)) {
  96                                 spin_unlock_irqrestore(&card->lock, flags);
  97                                 goto timed_out;
  98                         }
  99                         list_del_init(&t->link);
 100                         card->tlabel_mask &= ~(1ULL << t->tlabel);
 101                         break;
 102                 }
 103         }
 104         spin_unlock_irqrestore(&card->lock, flags);
 105
 106         if (&t->link != &card->transaction_list) {
 107                 t->callback(card, rcode, NULL, 0, t->callback_data);
 108                 return 0;
 109         }
 110
 111  timed_out:
 112         return -ENOENT;
 113 }
 114
 115 /*
 116  * Only valid for transactions that are potentially pending (ie have
 117  * been sent).
 118  */
 119 int fw_cancel_transaction(struct fw_card *card,
 120                           struct fw_transaction *transaction)
 121 {
 122         /*
 123          * Cancel the packet transmission if it's still queued.  That
 124          * will call the packet transmission callback which cancels
 125          * the transaction.
 126          */
 127
 128         if (card->driver->cancel_packet(card, &transaction->packet) == 0)
 129                 return 0;
 130
 131         /*
 132          * If the request packet has already been sent, we need to see
 133          * if the transaction is still pending and remove it in that case.
 134          */
 135
 136         return close_transaction(transaction, card, RCODE_CANCELLED);
 137 }
 138 EXPORT_SYMBOL(fw_cancel_transaction);
 139
 140 static void split_transaction_timeout_callback(struct timer_list *timer)
 141 {
 142         struct fw_transaction *t = from_timer(t, timer, split_timeout_timer);
 143         struct fw_card *card = t->card;
 144         unsigned long flags;
 145
 146         spin_lock_irqsave(&card->lock, flags);
 147         if (list_empty(&t->link)) {
 148                 spin_unlock_irqrestore(&card->lock, flags);
 149                 return;
 150         }
 151         list_del(&t->link);
 152         card->tlabel_mask &= ~(1ULL << t->tlabel);
 153         spin_unlock_irqrestore(&card->lock, flags);
 154
 155         t->callback(card, RCODE_CANCELLED, NULL, 0, t->callback_data);
 156 }
 157
 158 static void start_split_transaction_timeout(struct fw_transaction *t,
 159                                             struct fw_card *card)
 160 {
 161         unsigned long flags;
 162
 163         spin_lock_irqsave(&card->lock, flags);
 164
 165         if (list_empty(&t->link) || WARN_ON(t->is_split_transaction)) {
 166                 spin_unlock_irqrestore(&card->lock, flags);
 167                 return;
 168         }
 169
 170         t->is_split_transaction = true;
 171         mod_timer(&t->split_timeout_timer,
 172                   jiffies + card->split_timeout_jiffies);
 173
 174         spin_unlock_irqrestore(&card->lock, flags);
 175 }
 176
 177 static void transmit_complete_callback(struct fw_packet *packet,
 178                                        struct fw_card *card, int status)
 179 {
 180         struct fw_transaction *t =
 181             container_of(packet, struct fw_transaction, packet);
 182
 183         switch (status) {
 184         case ACK_COMPLETE:
 185                 close_transaction(t, card, RCODE_COMPLETE);
 186                 break;
 187         case ACK_PENDING:
 188                 start_split_transaction_timeout(t, card);
 189                 break;
 190         case ACK_BUSY_X:
 191         case ACK_BUSY_A:
 192         case ACK_BUSY_B:
 193                 close_transaction(t, card, RCODE_BUSY);
 194                 break;
 195         case ACK_DATA_ERROR:
 196                 close_transaction(t, card, RCODE_DATA_ERROR);
 197                 break;
 198         case ACK_TYPE_ERROR:
 199                 close_transaction(t, card, RCODE_TYPE_ERROR);
 200                 break;
 201         default:
 202                 /*
 203                  * In this case the ack is really a juju specific
 204                  * rcode, so just forward that to the callback.
 205                  */
 206                 close_transaction(t, card, status);
 207                 break;
 208         }
 209 }
 210
 211 static void fw_fill_request(struct fw_packet *packet, int tcode, int tlabel,
 212                 int destination_id, int source_id, int generation, int speed,
 213                 unsigned long long offset, void *payload, size_t length)
 214 {
 215         int ext_tcode;
 216
 217         if (tcode == TCODE_STREAM_DATA) {
 218                 packet->header[0] =
 219                         HEADER_DATA_LENGTH(length) |
 220                         destination_id |
 221                         HEADER_TCODE(TCODE_STREAM_DATA);
 222                 packet->header_length = 4;
 223                 packet->payload = payload;
 224                 packet->payload_length = length;
 225
 226                 goto common;
 227         }
 228
 229         if (tcode > 0x10) {
 230                 ext_tcode = tcode & ~0x10;
 231                 tcode = TCODE_LOCK_REQUEST;
 232         } else
 233                 ext_tcode = 0;
 234
 235         packet->header[0] =
 236                 HEADER_RETRY(RETRY_X) |
 237                 HEADER_TLABEL(tlabel) |
 238                 HEADER_TCODE(tcode) |
 239                 HEADER_DESTINATION(destination_id);
 240         packet->header[1] =
 241                 HEADER_OFFSET_HIGH(offset >> 32) | HEADER_SOURCE(source_id);
 242         packet->header[2] =
 243                 offset;
 244
 245         switch (tcode) {
 246         case TCODE_WRITE_QUADLET_REQUEST:
 247                 packet->header[3] = *(u32 *)payload;
 248                 packet->header_length = 16;
 249                 packet->payload_length = 0;
 250                 break;
 251
 252         case TCODE_LOCK_REQUEST:
 253         case TCODE_WRITE_BLOCK_REQUEST:
 254                 packet->header[3] =
 255                         HEADER_DATA_LENGTH(length) |
 256                         HEADER_EXTENDED_TCODE(ext_tcode);
 257                 packet->header_length = 16;
 258                 packet->payload = payload;
 259                 packet->payload_length = length;
 260                 break;
 261
 262         case TCODE_READ_QUADLET_REQUEST:
 263                 packet->header_length = 12;
 264                 packet->payload_length = 0;
 265                 break;
 266
 267         case TCODE_READ_BLOCK_REQUEST:
 268                 packet->header[3] =
 269                         HEADER_DATA_LENGTH(length) |
 270                         HEADER_EXTENDED_TCODE(ext_tcode);
 271                 packet->header_length = 16;
 272                 packet->payload_length = 0;
 273                 break;
 274
 275         default:
 276                 WARN(1, "wrong tcode %d\n", tcode);
 277         }
 278  common:
 279         packet->speed = speed;
 280         packet->generation = generation;
 281         packet->ack = 0;
 282         packet->payload_mapped = false;
 283 }
 284
 285 static int allocate_tlabel(struct fw_card *card)
 286 {
 287         int tlabel;
 288
 289         tlabel = card->current_tlabel;
 290         while (card->tlabel_mask & (1ULL << tlabel)) {
 291                 tlabel = (tlabel + 1) & 0x3f;
 292                 if (tlabel == card->current_tlabel)
 293                         return -EBUSY;
 294         }
 295
 296         card->current_tlabel = (tlabel + 1) & 0x3f;
 297         card->tlabel_mask |= 1ULL << tlabel;
 298
 299         return tlabel;
 300 }
 301
 302 /**
 303  * fw_send_request() - submit a request packet for transmission
 304  * @card:               interface to send the request at
 305  * @t:                  transaction instance to which the request belongs
 306  * @tcode:              transaction code
 307  * @destination_id:     destination node ID, consisting of bus_ID and phy_ID
 308  * @generation:         bus generation in which request and response are valid
 309  * @speed:              transmission speed
 310  * @offset:             48bit wide offset into destination's address space
 311  * @payload:            data payload for the request subaction
 312  * @length:             length of the payload, in bytes
 313  * @callback:           function to be called when the transaction is completed
 314  * @callback_data:      data to be passed to the transaction completion callback
 315  *
 316  * Submit a request packet into the asynchronous request transmission queue.
 317  * Can be called from atomic context.  If you prefer a blocking API, use
 318  * fw_run_transaction() in a context that can sleep.
 319  *
 320  * In case of lock requests, specify one of the firewire-core specific %TCODE_
 321  * constants instead of %TCODE_LOCK_REQUEST in @tcode.
 322  *
 323  * Make sure that the value in @destination_id is not older than the one in
 324  * @generation.  Otherwise the request is in danger to be sent to a wrong node.
 325  *
 326  * In case of asynchronous stream packets i.e. %TCODE_STREAM_DATA, the caller
 327  * needs to synthesize @destination_id with fw_stream_packet_destination_id().
 328  * It will contain tag, channel, and sy data instead of a node ID then.
 329  *
 330  * The payload buffer at @data is going to be DMA-mapped except in case of
 331  * @length <= 8 or of local (loopback) requests.  Hence make sure that the
 332  * buffer complies with the restrictions of the streaming DMA mapping API.
 333  * @payload must not be freed before the @callback is called.
 334  *
 335  * In case of request types without payload, @data is NULL and @length is 0.
 336  *
 337  * After the transaction is completed successfully or unsuccessfully, the
 338  * @callback will be called.  Among its parameters is the response code which
 339  * is either one of the rcodes per IEEE 1394 or, in case of internal errors,
 340  * the firewire-core specific %RCODE_SEND_ERROR.  The other firewire-core
 341  * specific rcodes (%RCODE_CANCELLED, %RCODE_BUSY, %RCODE_GENERATION,
 342  * %RCODE_NO_ACK) denote transaction timeout, busy responder, stale request
 343  * generation, or missing ACK respectively.
 344  *
 345  * Note some timing corner cases:  fw_send_request() may complete much earlier
 346  * than when the request packet actually hits the wire.  On the other hand,
 347  * transaction completion and hence execution of @callback may happen even
 348  * before fw_send_request() returns.
 349  */
 350 void fw_send_request(struct fw_card *card, struct fw_transaction *t, int tcode,
 351                      int destination_id, int generation, int speed,
 352                      unsigned long long offset, void *payload, size_t length,
 353                      fw_transaction_callback_t callback, void *callback_data)
 354 {
 355         unsigned long flags;
 356         int tlabel;
 357
 358         /*
 359          * Allocate tlabel from the bitmap and put the transaction on
 360          * the list while holding the card spinlock.
 361          */
 362
 363         spin_lock_irqsave(&card->lock, flags);
 364
 365         tlabel = allocate_tlabel(card);
 366         if (tlabel < 0) {
 367                 spin_unlock_irqrestore(&card->lock, flags);
 368                 callback(card, RCODE_SEND_ERROR, NULL, 0, callback_data);
 369                 return;
 370         }
 371
 372         t->node_id = destination_id;
 373         t->tlabel = tlabel;
 374         t->card = card;
 375         t->is_split_transaction = false;
 376         timer_setup(&t->split_timeout_timer,
 377                     split_transaction_timeout_callback, 0);
 378         t->callback = callback;
 379         t->callback_data = callback_data;
 380
 381         fw_fill_request(&t->packet, tcode, t->tlabel,
 382                         destination_id, card->node_id, generation,
 383                         speed, offset, payload, length);
 384         t->packet.callback = transmit_complete_callback;
 385
 386         list_add_tail(&t->link, &card->transaction_list);
 387
 388         spin_unlock_irqrestore(&card->lock, flags);
 389
 390         card->driver->send_request(card, &t->packet);
 391 }
 392 EXPORT_SYMBOL(fw_send_request);
 393
 394 struct transaction_callback_data {
 395         struct completion done;
 396         void *payload;
 397         int rcode;
 398 };
 399
 400 static void transaction_callback(struct fw_card *card, int rcode,
 401                                  void *payload, size_t length, void *data)
 402 {
 403         struct transaction_callback_data *d = data;
 404
 405         if (rcode == RCODE_COMPLETE)
 406                 memcpy(d->payload, payload, length);
 407         d->rcode = rcode;
 408         complete(&d->done);
 409 }
 410
 411 /**
 412  * fw_run_transaction() - send request and sleep until transaction is completed
 413  * @card:               card interface for this request
 414  * @tcode:              transaction code
 415  * @destination_id:     destination node ID, consisting of bus_ID and phy_ID
 416  * @generation:         bus generation in which request and response are valid
 417  * @speed:              transmission speed
 418  * @offset:             48bit wide offset into destination's address space
 419  * @payload:            data payload for the request subaction
 420  * @length:             length of the payload, in bytes
 421  *
 422  * Returns the RCODE.  See fw_send_request() for parameter documentation.
 423  * Unlike fw_send_request(), @data points to the payload of the request or/and
 424  * to the payload of the response.  DMA mapping restrictions apply to outbound
 425  * request payloads of >= 8 bytes but not to inbound response payloads.
 426  */
 427 int fw_run_transaction(struct fw_card *card, int tcode, int destination_id,
 428                        int generation, int speed, unsigned long long offset,
 429                        void *payload, size_t length)
 430 {
 431         struct transaction_callback_data d;
 432         struct fw_transaction t;
 433
 434         timer_setup_on_stack(&t.split_timeout_timer, NULL, 0);
 435         init_completion(&d.done);
 436         d.payload = payload;
 437         fw_send_request(card, &t, tcode, destination_id, generation, speed,
 438                         offset, payload, length, transaction_callback, &d);
 439         wait_for_completion(&d.done);
 440         destroy_timer_on_stack(&t.split_timeout_timer);
 441
 442         return d.rcode;
 443 }
 444 EXPORT_SYMBOL(fw_run_transaction);
 445
 446 static DEFINE_MUTEX(phy_config_mutex);
 447 static DECLARE_COMPLETION(phy_config_done);
 448
 449 static void transmit_phy_packet_callback(struct fw_packet *packet,
 450                                          struct fw_card *card, int status)
 451 {
 452         complete(&phy_config_done);
 453 }
 454
 455 static struct fw_packet phy_config_packet = {
 456         .header_length  = 12,
 457         .header[0]      = TCODE_LINK_INTERNAL << 4,
 458         .payload_length = 0,
 459         .speed          = SCODE_100,
 460         .callback       = transmit_phy_packet_callback,
 461 };
 462
 463 void fw_send_phy_config(struct fw_card *card,
 464                         int node_id, int generation, int gap_count)
 465 {
 466         long timeout = DIV_ROUND_UP(HZ, 10);
 467         u32 data = PHY_IDENTIFIER(PHY_PACKET_CONFIG);
 468
 469         if (node_id != FW_PHY_CONFIG_NO_NODE_ID)
 470                 data |= PHY_CONFIG_ROOT_ID(node_id);
 471
 472         if (gap_count == FW_PHY_CONFIG_CURRENT_GAP_COUNT) {
 473                 gap_count = card->driver->read_phy_reg(card, 1);
 474                 if (gap_count < 0)
 475                         return;
 476
 477                 gap_count &= 63;
 478                 if (gap_count == 63)
 479                         return;
 480         }
 481         data |= PHY_CONFIG_GAP_COUNT(gap_count);
 482
 483         mutex_lock(&phy_config_mutex);
 484
 485         phy_config_packet.header[1] = data;
 486         phy_config_packet.header[2] = ~data;
 487         phy_config_packet.generation = generation;
 488         reinit_completion(&phy_config_done);
 489
 490         card->driver->send_request(card, &phy_config_packet);
 491         wait_for_completion_timeout(&phy_config_done, timeout);
 492
 493         mutex_unlock(&phy_config_mutex);
 494 }
 495
 496 static struct fw_address_handler *lookup_overlapping_address_handler(
 497         struct list_head *list, unsigned long long offset, size_t length)
 498 {
 499         struct fw_address_handler *handler;
 500
 501         list_for_each_entry_rcu(handler, list, link) {
 502                 if (handler->offset < offset + length &&
 503                     offset < handler->offset + handler->length)
 504                         return handler;
 505         }
 506
 507         return NULL;
 508 }
 509
 510 static bool is_enclosing_handler(struct fw_address_handler *handler,
 511                                  unsigned long long offset, size_t length)
 512 {
 513         return handler->offset <= offset &&
 514                 offset + length <= handler->offset + handler->length;
 515 }
 516
 517 static struct fw_address_handler *lookup_enclosing_address_handler(
 518         struct list_head *list, unsigned long long offset, size_t length)
 519 {
 520         struct fw_address_handler *handler;
 521
 522         list_for_each_entry_rcu(handler, list, link) {
 523                 if (is_enclosing_handler(handler, offset, length))
 524                         return handler;
 525         }
 526
 527         return NULL;
 528 }
 529
 530 static DEFINE_SPINLOCK(address_handler_list_lock);
 531 static LIST_HEAD(address_handler_list);
 532
 533 const struct fw_address_region fw_high_memory_region =
 534         { .start = FW_MAX_PHYSICAL_RANGE, .end = 0xffffe0000000ULL, };
 535 EXPORT_SYMBOL(fw_high_memory_region);
 536
 537 static const struct fw_address_region low_memory_region =
 538         { .start = 0x000000000000ULL, .end = FW_MAX_PHYSICAL_RANGE, };
 539
 540 #if 0
 541 const struct fw_address_region fw_private_region =
 542         { .start = 0xffffe0000000ULL, .end = 0xfffff0000000ULL,  };
 543 const struct fw_address_region fw_csr_region =
 544         { .start = CSR_REGISTER_BASE,
 545           .end   = CSR_REGISTER_BASE | CSR_CONFIG_ROM_END,  };
 546 const struct fw_address_region fw_unit_space_region =
 547         { .start = 0xfffff0000900ULL, .end = 0x1000000000000ULL, };
 548 #endif  /*  0  */
 549
 550 static bool is_in_fcp_region(u64 offset, size_t length)
 551 {
 552         return offset >= (CSR_REGISTER_BASE | CSR_FCP_COMMAND) &&
 553                 offset + length <= (CSR_REGISTER_BASE | CSR_FCP_END);
 554 }
 555
 556 /**
 557  * fw_core_add_address_handler() - register for incoming requests
 558  * @handler:    callback
 559  * @region:     region in the IEEE 1212 node space address range
 560  *
 561  * region->start, ->end, and handler->length have to be quadlet-aligned.
 562  *
 563  * When a request is received that falls within the specified address range,
 564  * the specified callback is invoked.  The parameters passed to the callback
 565  * give the details of the particular request.
 566  *
 567  * To be called in process context.
 568  * Return value:  0 on success, non-zero otherwise.
 569  *
 570  * The start offset of the handler's address region is determined by
 571  * fw_core_add_address_handler() and is returned in handler->offset.
 572  *
 573  * Address allocations are exclusive, except for the FCP registers.
 574  */
 575 int fw_core_add_address_handler(struct fw_address_handler *handler,
 576                                 const struct fw_address_region *region)
 577 {
 578         struct fw_address_handler *other;
 579         int ret = -EBUSY;
 580
 581         if (region->start & 0xffff000000000003ULL ||
 582             region->start >= region->end ||
 583             region->end   > 0x0001000000000000ULL ||
 584             handler->length & 3 ||
 585             handler->length == 0)
 586                 return -EINVAL;
 587
 588         spin_lock(&address_handler_list_lock);
 589
 590         handler->offset = region->start;
 591         while (handler->offset + handler->length <= region->end) {
 592                 if (is_in_fcp_region(handler->offset, handler->length))
 593                         other = NULL;
 594                 else
 595                         other = lookup_overlapping_address_handler
 596                                         (&address_handler_list,
 597                                          handler->offset, handler->length);
 598                 if (other != NULL) {
 599                         handler->offset += other->length;
 600                 } else {
 601                         list_add_tail_rcu(&handler->link, &address_handler_list);
 602                         ret = 0;
 603                         break;
 604                 }
 605         }
 606
 607         spin_unlock(&address_handler_list_lock);
 608
 609         return ret;
 610 }
 611 EXPORT_SYMBOL(fw_core_add_address_handler);
 612
 613 /**
 614  * fw_core_remove_address_handler() - unregister an address handler
 615  * @handler: callback
 616  *
 617  * To be called in process context.
 618  *
 619  * When fw_core_remove_address_handler() returns, @handler->callback() is
 620  * guaranteed to not run on any CPU anymore.
 621  */
 622 void fw_core_remove_address_handler(struct fw_address_handler *handler)
 623 {
 624         spin_lock(&address_handler_list_lock);
 625         list_del_rcu(&handler->link);
 626         spin_unlock(&address_handler_list_lock);
 627         synchronize_rcu();
 628 }
 629 EXPORT_SYMBOL(fw_core_remove_address_handler);
 630
 631 struct fw_request {
 632         struct fw_packet response;
 633         u32 request_header[4];
 634         int ack;
 635         u32 length;
 636         u32 data[0];
 637 };
 638
 639 static void free_response_callback(struct fw_packet *packet,
 640                                    struct fw_card *card, int status)
 641 {
 642         struct fw_request *request;
 643
 644         request = container_of(packet, struct fw_request, response);
 645         kfree(request);
 646 }
 647
 648 int fw_get_response_length(struct fw_request *r)
 649 {
 650         int tcode, ext_tcode, data_length;
 651
 652         tcode = HEADER_GET_TCODE(r->request_header[0]);
 653
 654         switch (tcode) {
 655         case TCODE_WRITE_QUADLET_REQUEST:
 656         case TCODE_WRITE_BLOCK_REQUEST:
 657                 return 0;
 658
 659         case TCODE_READ_QUADLET_REQUEST:
 660                 return 4;
 661
 662         case TCODE_READ_BLOCK_REQUEST:
 663                 data_length = HEADER_GET_DATA_LENGTH(r->request_header[3]);
 664                 return data_length;
 665
 666         case TCODE_LOCK_REQUEST:
 667                 ext_tcode = HEADER_GET_EXTENDED_TCODE(r->request_header[3]);
 668                 data_length = HEADER_GET_DATA_LENGTH(r->request_header[3]);
 669                 switch (ext_tcode) {
 670                 case EXTCODE_FETCH_ADD:
 671                 case EXTCODE_LITTLE_ADD:
 672                         return data_length;
 673                 default:
 674                         return data_length / 2;
 675                 }
 676
 677         default:
 678                 WARN(1, "wrong tcode %d\n", tcode);
 679                 return 0;
 680         }
 681 }
 682
 683 void fw_fill_response(struct fw_packet *response, u32 *request_header,
 684                       int rcode, void *payload, size_t length)
 685 {
 686         int tcode, tlabel, extended_tcode, source, destination;
 687
 688         tcode          = HEADER_GET_TCODE(request_header[0]);
 689         tlabel         = HEADER_GET_TLABEL(request_header[0]);
 690         source         = HEADER_GET_DESTINATION(request_header[0]);
 691         destination    = HEADER_GET_SOURCE(request_header[1]);
 692         extended_tcode = HEADER_GET_EXTENDED_TCODE(request_header[3]);
 693
 694         response->header[0] =
 695                 HEADER_RETRY(RETRY_1) |
 696                 HEADER_TLABEL(tlabel) |
 697                 HEADER_DESTINATION(destination);
 698         response->header[1] =
 699                 HEADER_SOURCE(source) |
 700                 HEADER_RCODE(rcode);
 701         response->header[2] = 0;
 702
 703         switch (tcode) {
 704         case TCODE_WRITE_QUADLET_REQUEST:
 705         case TCODE_WRITE_BLOCK_REQUEST:
 706                 response->header[0] |= HEADER_TCODE(TCODE_WRITE_RESPONSE);
 707                 response->header_length = 12;
 708                 response->payload_length = 0;
 709                 break;
 710
 711         case TCODE_READ_QUADLET_REQUEST:
 712                 response->header[0] |=
 713                         HEADER_TCODE(TCODE_READ_QUADLET_RESPONSE);
 714                 if (payload != NULL)
 715                         response->header[3] = *(u32 *)payload;
 716                 else
 717                         response->header[3] = 0;
 718                 response->header_length = 16;
 719                 response->payload_length = 0;
 720                 break;
 721
 722         case TCODE_READ_BLOCK_REQUEST:
 723         case TCODE_LOCK_REQUEST:
 724                 response->header[0] |= HEADER_TCODE(tcode + 2);
 725                 response->header[3] =
 726                         HEADER_DATA_LENGTH(length) |
 727                         HEADER_EXTENDED_TCODE(extended_tcode);
 728                 response->header_length = 16;
 729                 response->payload = payload;
 730                 response->payload_length = length;
 731                 break;
 732
 733         default:
 734                 WARN(1, "wrong tcode %d\n", tcode);
 735         }
 736
 737         response->payload_mapped = false;
 738 }
 739 EXPORT_SYMBOL(fw_fill_response);
 740
 741 static u32 compute_split_timeout_timestamp(struct fw_card *card,
 742                                            u32 request_timestamp)
 743 {
 744         unsigned int cycles;
 745         u32 timestamp;
 746
 747         cycles = card->split_timeout_cycles;
 748         cycles += request_timestamp & 0x1fff;
 749
 750         timestamp = request_timestamp & ~0x1fff;
 751         timestamp += (cycles / 8000) << 13;
 752         timestamp |= cycles % 8000;
 753
 754         return timestamp;
 755 }
 756
 757 static struct fw_request *allocate_request(struct fw_card *card,
 758                                            struct fw_packet *p)
 759 {
 760         struct fw_request *request;
 761         u32 *data, length;
 762         int request_tcode;
 763
 764         request_tcode = HEADER_GET_TCODE(p->header[0]);
 765         switch (request_tcode) {
 766         case TCODE_WRITE_QUADLET_REQUEST:
 767                 data = &p->header[3];
 768                 length = 4;
 769                 break;
 770
 771         case TCODE_WRITE_BLOCK_REQUEST:
 772         case TCODE_LOCK_REQUEST:
 773                 data = p->payload;
 774                 length = HEADER_GET_DATA_LENGTH(p->header[3]);
 775                 break;
 776
 777         case TCODE_READ_QUADLET_REQUEST:
 778                 data = NULL;
 779                 length = 4;
 780                 break;
 781
 782         case TCODE_READ_BLOCK_REQUEST:
 783                 data = NULL;
 784                 length = HEADER_GET_DATA_LENGTH(p->header[3]);
 785                 break;
 786
 787         default:
 788                 fw_notice(card, "ERROR - corrupt request received - %08x %08x %08x\n",
 789                          p->header[0], p->header[1], p->header[2]);
 790                 return NULL;
 791         }
 792
 793         request = kmalloc(sizeof(*request) + length, GFP_ATOMIC);
 794         if (request == NULL)
 795                 return NULL;
 796
 797         request->response.speed = p->speed;
 798         request->response.timestamp =
 799                         compute_split_timeout_timestamp(card, p->timestamp);
 800         request->response.generation = p->generation;
 801         request->response.ack = 0;
 802         request->response.callback = free_response_callback;
 803         request->ack = p->ack;
 804         request->length = length;
 805         if (data)
 806                 memcpy(request->data, data, length);
 807
 808         memcpy(request->request_header, p->header, sizeof(p->header));
 809
 810         return request;
 811 }
 812
 813 void fw_send_response(struct fw_card *card,
 814                       struct fw_request *request, int rcode)
 815 {
 816         if (WARN_ONCE(!request, "invalid for FCP address handlers"))
 817                 return;
 818
 819         /* unified transaction or broadcast transaction: don't respond */
 820         if (request->ack != ACK_PENDING ||
 821             HEADER_DESTINATION_IS_BROADCAST(request->request_header[0])) {
 822                 kfree(request);
 823                 return;
 824         }
 825
 826         if (rcode == RCODE_COMPLETE)
 827                 fw_fill_response(&request->response, request->request_header,
 828                                  rcode, request->data,
 829                                  fw_get_response_length(request));
 830         else
 831                 fw_fill_response(&request->response, request->request_header,
 832                                  rcode, NULL, 0);
 833
 834         card->driver->send_response(card, &request->response);
 835 }
 836 EXPORT_SYMBOL(fw_send_response);
 837
 838 /**
 839  * fw_get_request_speed() - returns speed at which the @request was received
 840  * @request: firewire request data
 841  */
 842 int fw_get_request_speed(struct fw_request *request)
 843 {
 844         return request->response.speed;
 845 }
 846 EXPORT_SYMBOL(fw_get_request_speed);
 847
 848 static void handle_exclusive_region_request(struct fw_card *card,
 849                                             struct fw_packet *p,
 850                                             struct fw_request *request,
 851                                             unsigned long long offset)
 852 {
 853         struct fw_address_handler *handler;
 854         int tcode, destination, source;
 855
 856         destination = HEADER_GET_DESTINATION(p->header[0]);
 857         source      = HEADER_GET_SOURCE(p->header[1]);
 858         tcode       = HEADER_GET_TCODE(p->header[0]);
 859         if (tcode == TCODE_LOCK_REQUEST)
 860                 tcode = 0x10 + HEADER_GET_EXTENDED_TCODE(p->header[3]);
 861
 862         rcu_read_lock();
 863         handler = lookup_enclosing_address_handler(&address_handler_list,
 864                                                    offset, request->length);
 865         if (handler)
 866                 handler->address_callback(card, request,
 867                                           tcode, destination, source,
 868                                           p->generation, offset,
 869                                           request->data, request->length,
 870                                           handler->callback_data);
 871         rcu_read_unlock();
 872
 873         if (!handler)
 874                 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
 875 }
 876
 877 static void handle_fcp_region_request(struct fw_card *card,
 878                                       struct fw_packet *p,
 879                                       struct fw_request *request,
 880                                       unsigned long long offset)
 881 {
 882         struct fw_address_handler *handler;
 883         int tcode, destination, source;
 884
 885         if ((offset != (CSR_REGISTER_BASE | CSR_FCP_COMMAND) &&
 886              offset != (CSR_REGISTER_BASE | CSR_FCP_RESPONSE)) ||
 887             request->length > 0x200) {
 888                 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
 889
 890                 return;
 891         }
 892
 893         tcode       = HEADER_GET_TCODE(p->header[0]);
 894         destination = HEADER_GET_DESTINATION(p->header[0]);
 895         source      = HEADER_GET_SOURCE(p->header[1]);
 896
 897         if (tcode != TCODE_WRITE_QUADLET_REQUEST &&
 898             tcode != TCODE_WRITE_BLOCK_REQUEST) {
 899                 fw_send_response(card, request, RCODE_TYPE_ERROR);
 900
 901                 return;
 902         }
 903
 904         rcu_read_lock();
 905         list_for_each_entry_rcu(handler, &address_handler_list, link) {
 906                 if (is_enclosing_handler(handler, offset, request->length))
 907                         handler->address_callback(card, NULL, tcode,
 908                                                   destination, source,
 909                                                   p->generation, offset,
 910                                                   request->data,
 911                                                   request->length,
 912                                                   handler->callback_data);
 913         }
 914         rcu_read_unlock();
 915
 916         fw_send_response(card, request, RCODE_COMPLETE);
 917 }
 918
 919 void fw_core_handle_request(struct fw_card *card, struct fw_packet *p)
 920 {
 921         struct fw_request *request;
 922         unsigned long long offset;
 923
 924         if (p->ack != ACK_PENDING && p->ack != ACK_COMPLETE)
 925                 return;
 926
 927         if (TCODE_IS_LINK_INTERNAL(HEADER_GET_TCODE(p->header[0]))) {
 928                 fw_cdev_handle_phy_packet(card, p);
 929                 return;
 930         }
 931
 932         request = allocate_request(card, p);
 933         if (request == NULL) {
 934                 /* FIXME: send statically allocated busy packet. */
 935                 return;
 936         }
 937
 938         offset = ((u64)HEADER_GET_OFFSET_HIGH(p->header[1]) << 32) |
 939                 p->header[2];
 940
 941         if (!is_in_fcp_region(offset, request->length))
 942                 handle_exclusive_region_request(card, p, request, offset);
 943         else
 944                 handle_fcp_region_request(card, p, request, offset);
 945
 946 }
 947 EXPORT_SYMBOL(fw_core_handle_request);
 948
 949 void fw_core_handle_response(struct fw_card *card, struct fw_packet *p)
 950 {
 951         struct fw_transaction *t;
 952         unsigned long flags;
 953         u32 *data;
 954         size_t data_length;
 955         int tcode, tlabel, source, rcode;
 956
 957         tcode   = HEADER_GET_TCODE(p->header[0]);
 958         tlabel  = HEADER_GET_TLABEL(p->header[0]);
 959         source  = HEADER_GET_SOURCE(p->header[1]);
 960         rcode   = HEADER_GET_RCODE(p->header[1]);
 961
 962         spin_lock_irqsave(&card->lock, flags);
 963         list_for_each_entry(t, &card->transaction_list, link) {
 964                 if (t->node_id == source && t->tlabel == tlabel) {
 965                         if (!try_cancel_split_timeout(t)) {
 966                                 spin_unlock_irqrestore(&card->lock, flags);
 967                                 goto timed_out;
 968                         }
 969                         list_del_init(&t->link);
 970                         card->tlabel_mask &= ~(1ULL << t->tlabel);
 971                         break;
 972                 }
 973         }
 974         spin_unlock_irqrestore(&card->lock, flags);
 975
 976         if (&t->link == &card->transaction_list) {
 977  timed_out:
 978                 fw_notice(card, "unsolicited response (source %x, tlabel %x)\n",
 979                           source, tlabel);
 980                 return;
 981         }
 982
 983         /*
 984          * FIXME: sanity check packet, is length correct, does tcodes
 985          * and addresses match.
 986          */
 987
 988         switch (tcode) {
 989         case TCODE_READ_QUADLET_RESPONSE:
 990                 data = (u32 *) &p->header[3];
 991                 data_length = 4;
 992                 break;
 993
 994         case TCODE_WRITE_RESPONSE:
 995                 data = NULL;
 996                 data_length = 0;
 997                 break;
 998
 999         case TCODE_READ_BLOCK_RESPONSE:
1000         case TCODE_LOCK_RESPONSE:
1001                 data = p->payload;
1002                 data_length = HEADER_GET_DATA_LENGTH(p->header[3]);
1003                 break;
1004
1005         default:
1006                 /* Should never happen, this is just to shut up gcc. */
1007                 data = NULL;
1008                 data_length = 0;
1009                 break;
1010         }
1011
1012         /*
1013          * The response handler may be executed while the request handler
1014          * is still pending.  Cancel the request handler.
1015          */
1016         card->driver->cancel_packet(card, &t->packet);
1017
1018         t->callback(card, rcode, data, data_length, t->callback_data);
1019 }
1020 EXPORT_SYMBOL(fw_core_handle_response);
1021
1022 /**
1023  * fw_rcode_string - convert a firewire result code to an error description
1024  * @rcode: the result code
1025  */
1026 const char *fw_rcode_string(int rcode)
1027 {
1028         static const char *const names[] = {
1029                 [RCODE_COMPLETE]       = "no error",
1030                 [RCODE_CONFLICT_ERROR] = "conflict error",
1031                 [RCODE_DATA_ERROR]     = "data error",
1032                 [RCODE_TYPE_ERROR]     = "type error",
1033                 [RCODE_ADDRESS_ERROR]  = "address error",
1034                 [RCODE_SEND_ERROR]     = "send error",
1035                 [RCODE_CANCELLED]      = "timeout",
1036                 [RCODE_BUSY]           = "busy",
1037                 [RCODE_GENERATION]     = "bus reset",
1038                 [RCODE_NO_ACK]         = "no ack",
1039         };
1040
1041         if ((unsigned int)rcode < ARRAY_SIZE(names) && names[rcode])
1042                 return names[rcode];
1043         else
1044                 return "unknown";
1045 }
1046 EXPORT_SYMBOL(fw_rcode_string);
1047
1048 static const struct fw_address_region topology_map_region =
1049         { .start = CSR_REGISTER_BASE | CSR_TOPOLOGY_MAP,
1050           .end   = CSR_REGISTER_BASE | CSR_TOPOLOGY_MAP_END, };
1051
1052 static void handle_topology_map(struct fw_card *card, struct fw_request *request,
1053                 int tcode, int destination, int source, int generation,
1054                 unsigned long long offset, void *payload, size_t length,
1055                 void *callback_data)
1056 {
1057         int start;
1058
1059         if (!TCODE_IS_READ_REQUEST(tcode)) {
1060                 fw_send_response(card, request, RCODE_TYPE_ERROR);
1061                 return;
1062         }
1063
1064         if ((offset & 3) > 0 || (length & 3) > 0) {
1065                 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
1066                 return;
1067         }
1068
1069         start = (offset - topology_map_region.start) / 4;
1070         memcpy(payload, &card->topology_map[start], length);
1071
1072         fw_send_response(card, request, RCODE_COMPLETE);
1073 }
1074
1075 static struct fw_address_handler topology_map = {
1076         .length                 = 0x400,
1077         .address_callback       = handle_topology_map,
1078 };
1079
1080 static const struct fw_address_region registers_region =
1081         { .start = CSR_REGISTER_BASE,
1082           .end   = CSR_REGISTER_BASE | CSR_CONFIG_ROM, };
1083
1084 static void update_split_timeout(struct fw_card *card)
1085 {
1086         unsigned int cycles;
1087
1088         cycles = card->split_timeout_hi * 8000 + (card->split_timeout_lo >> 19);
1089
1090         /* minimum per IEEE 1394, maximum which doesn't overflow OHCI */
1091         cycles = clamp(cycles, 800u, 3u * 8000u);
1092
1093         card->split_timeout_cycles = cycles;
1094         card->split_timeout_jiffies = DIV_ROUND_UP(cycles * HZ, 8000);
1095 }
1096
1097 static void handle_registers(struct fw_card *card, struct fw_request *request,
1098                 int tcode, int destination, int source, int generation,
1099                 unsigned long long offset, void *payload, size_t length,
1100                 void *callback_data)
1101 {
1102         int reg = offset & ~CSR_REGISTER_BASE;
1103         __be32 *data = payload;
1104         int rcode = RCODE_COMPLETE;
1105         unsigned long flags;
1106
1107         switch (reg) {
1108         case CSR_PRIORITY_BUDGET:
1109                 if (!card->priority_budget_implemented) {
1110                         rcode = RCODE_ADDRESS_ERROR;
1111                         break;
1112                 }
1113                 /* else fall through */
1114
1115         case CSR_NODE_IDS:
1116                 /*
1117                  * per IEEE 1394-2008 8.3.22.3, not IEEE 1394.1-2004 3.2.8
1118                  * and 9.6, but interoperable with IEEE 1394.1-2004 bridges
1119                  */
1120                 /* fall through */
1121
1122         case CSR_STATE_CLEAR:
1123         case CSR_STATE_SET:
1124         case CSR_CYCLE_TIME:
1125         case CSR_BUS_TIME:
1126         case CSR_BUSY_TIMEOUT:
1127                 if (tcode == TCODE_READ_QUADLET_REQUEST)
1128                         *data = cpu_to_be32(card->driver->read_csr(card, reg));
1129                 else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1130                         card->driver->write_csr(card, reg, be32_to_cpu(*data));
1131                 else
1132                         rcode = RCODE_TYPE_ERROR;
1133                 break;
1134
1135         case CSR_RESET_START:
1136                 if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1137                         card->driver->write_csr(card, CSR_STATE_CLEAR,
1138                                                 CSR_STATE_BIT_ABDICATE);
1139                 else
1140                         rcode = RCODE_TYPE_ERROR;
1141                 break;
1142
1143         case CSR_SPLIT_TIMEOUT_HI:
1144                 if (tcode == TCODE_READ_QUADLET_REQUEST) {
1145                         *data = cpu_to_be32(card->split_timeout_hi);
1146                 } else if (tcode == TCODE_WRITE_QUADLET_REQUEST) {
1147                         spin_lock_irqsave(&card->lock, flags);
1148                         card->split_timeout_hi = be32_to_cpu(*data) & 7;
1149                         update_split_timeout(card);
1150                         spin_unlock_irqrestore(&card->lock, flags);
1151                 } else {
1152                         rcode = RCODE_TYPE_ERROR;
1153                 }
1154                 break;
1155
1156         case CSR_SPLIT_TIMEOUT_LO:
1157                 if (tcode == TCODE_READ_QUADLET_REQUEST) {
1158                         *data = cpu_to_be32(card->split_timeout_lo);
1159                 } else if (tcode == TCODE_WRITE_QUADLET_REQUEST) {
1160                         spin_lock_irqsave(&card->lock, flags);
1161                         card->split_timeout_lo =
1162                                         be32_to_cpu(*data) & 0xfff80000;
1163                         update_split_timeout(card);
1164                         spin_unlock_irqrestore(&card->lock, flags);
1165                 } else {
1166                         rcode = RCODE_TYPE_ERROR;
1167                 }
1168                 break;
1169
1170         case CSR_MAINT_UTILITY:
1171                 if (tcode == TCODE_READ_QUADLET_REQUEST)
1172                         *data = card->maint_utility_register;
1173                 else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1174                         card->maint_utility_register = *data;
1175                 else
1176                         rcode = RCODE_TYPE_ERROR;
1177                 break;
1178
1179         case CSR_BROADCAST_CHANNEL:
1180                 if (tcode == TCODE_READ_QUADLET_REQUEST)
1181                         *data = cpu_to_be32(card->broadcast_channel);
1182                 else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1183                         card->broadcast_channel =
1184                             (be32_to_cpu(*data) & BROADCAST_CHANNEL_VALID) |
1185                             BROADCAST_CHANNEL_INITIAL;
1186                 else
1187                         rcode = RCODE_TYPE_ERROR;
1188                 break;
1189
1190         case CSR_BUS_MANAGER_ID:
1191         case CSR_BANDWIDTH_AVAILABLE:
1192         case CSR_CHANNELS_AVAILABLE_HI:
1193         case CSR_CHANNELS_AVAILABLE_LO:
1194                 /*
1195                  * FIXME: these are handled by the OHCI hardware and
1196                  * the stack never sees these request. If we add
1197                  * support for a new type of controller that doesn't
1198                  * handle this in hardware we need to deal with these
1199                  * transactions.
1200                  */
1201                 BUG();
1202                 break;
1203
1204         default:
1205                 rcode = RCODE_ADDRESS_ERROR;
1206                 break;
1207         }
1208
1209         fw_send_response(card, request, rcode);
1210 }
1211
1212 static struct fw_address_handler registers = {
1213         .length                 = 0x400,
1214         .address_callback       = handle_registers,
1215 };
1216
1217 static void handle_low_memory(struct fw_card *card, struct fw_request *request,
1218                 int tcode, int destination, int source, int generation,
1219                 unsigned long long offset, void *payload, size_t length,
1220                 void *callback_data)
1221 {
1222         /*
1223          * This catches requests not handled by the physical DMA unit,
1224          * i.e., wrong transaction types or unauthorized source nodes.
1225          */
1226         fw_send_response(card, request, RCODE_TYPE_ERROR);
1227 }
1228
1229 static struct fw_address_handler low_memory = {
1230         .length                 = FW_MAX_PHYSICAL_RANGE,
1231         .address_callback       = handle_low_memory,
1232 };
1233
1234 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1235 MODULE_DESCRIPTION("Core IEEE1394 transaction logic");
1236 MODULE_LICENSE("GPL");
1237
1238 static const u32 vendor_textual_descriptor[] = {
1239         /* textual descriptor leaf () */
1240         0x00060000,
1241         0x00000000,
1242         0x00000000,
1243         0x4c696e75,             /* L i n u */
1244         0x78204669,             /* x   F i */
1245         0x72657769,             /* r e w i */
1246         0x72650000,             /* r e     */
1247 };
1248
1249 static const u32 model_textual_descriptor[] = {
1250         /* model descriptor leaf () */
1251         0x00030000,
1252         0x00000000,
1253         0x00000000,
1254         0x4a756a75,             /* J u j u */
1255 };
1256
1257 static struct fw_descriptor vendor_id_descriptor = {
1258         .length = ARRAY_SIZE(vendor_textual_descriptor),
1259         .immediate = 0x03001f11,
1260         .key = 0x81000000,
1261         .data = vendor_textual_descriptor,
1262 };
1263
1264 static struct fw_descriptor model_id_descriptor = {
1265         .length = ARRAY_SIZE(model_textual_descriptor),
1266         .immediate = 0x17023901,
1267         .key = 0x81000000,
1268         .data = model_textual_descriptor,
1269 };
1270
1271 static int __init fw_core_init(void)
1272 {
1273         int ret;
1274
1275         fw_workqueue = alloc_workqueue("firewire", WQ_MEM_RECLAIM, 0);
1276         if (!fw_workqueue)
1277                 return -ENOMEM;
1278
1279         ret = bus_register(&fw_bus_type);
1280         if (ret < 0) {
1281                 destroy_workqueue(fw_workqueue);
1282                 return ret;
1283         }
1284
1285         fw_cdev_major = register_chrdev(0, "firewire", &fw_device_ops);
1286         if (fw_cdev_major < 0) {
1287                 bus_unregister(&fw_bus_type);
1288                 destroy_workqueue(fw_workqueue);
1289                 return fw_cdev_major;
1290         }
1291
1292         fw_core_add_address_handler(&topology_map, &topology_map_region);
1293         fw_core_add_address_handler(&registers, &registers_region);
1294         fw_core_add_address_handler(&low_memory, &low_memory_region);
1295         fw_core_add_descriptor(&vendor_id_descriptor);
1296         fw_core_add_descriptor(&model_id_descriptor);
1297
1298         return 0;
1299 }
1300
1301 static void __exit fw_core_cleanup(void)
1302 {
1303         unregister_chrdev(fw_cdev_major, "firewire");
1304         bus_unregister(&fw_bus_type);
1305         destroy_workqueue(fw_workqueue);
1306         idr_destroy(&fw_device_idr);
1307 }
1308
1309 module_init(fw_core_init);
1310 module_exit(fw_core_cleanup);