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, struct fw_card *card, int rcode,
  74                              u32 response_tstamp)
  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                 if (!t->with_tstamp) {
  96                         t->callback.without_tstamp(card, rcode, NULL, 0, t->callback_data);
  97                 } else {
  98                         t->callback.with_tstamp(card, rcode, t->packet.timestamp, response_tstamp,
  99                                                 NULL, 0, t->callback_data);
 100                 }
 101                 return 0;
 102         }
 103
 104  timed_out:
 105         return -ENOENT;
 106 }
 107
 108 /*
 109  * Only valid for transactions that are potentially pending (ie have
 110  * been sent).
 111  */
 112 int fw_cancel_transaction(struct fw_card *card,
 113                           struct fw_transaction *transaction)
 114 {
 115         u32 tstamp;
 116
 117         /*
 118          * Cancel the packet transmission if it's still queued.  That
 119          * will call the packet transmission callback which cancels
 120          * the transaction.
 121          */
 122
 123         if (card->driver->cancel_packet(card, &transaction->packet) == 0)
 124                 return 0;
 125
 126         /*
 127          * If the request packet has already been sent, we need to see
 128          * if the transaction is still pending and remove it in that case.
 129          */
 130
 131         if (transaction->packet.ack == 0) {
 132                 // The timestamp is reused since it was just read now.
 133                 tstamp = transaction->packet.timestamp;
 134         } else {
 135                 u32 curr_cycle_time = 0;
 136
 137                 (void)fw_card_read_cycle_time(card, &curr_cycle_time);
 138                 tstamp = cycle_time_to_ohci_tstamp(curr_cycle_time);
 139         }
 140
 141         return close_transaction(transaction, card, RCODE_CANCELLED, tstamp);
 142 }
 143 EXPORT_SYMBOL(fw_cancel_transaction);
 144
 145 static void split_transaction_timeout_callback(struct timer_list *timer)
 146 {
 147         struct fw_transaction *t = from_timer(t, timer, split_timeout_timer);
 148         struct fw_card *card = t->card;
 149         unsigned long flags;
 150
 151         spin_lock_irqsave(&card->lock, flags);
 152         if (list_empty(&t->link)) {
 153                 spin_unlock_irqrestore(&card->lock, flags);
 154                 return;
 155         }
 156         list_del(&t->link);
 157         card->tlabel_mask &= ~(1ULL << t->tlabel);
 158         spin_unlock_irqrestore(&card->lock, flags);
 159
 160         if (!t->with_tstamp) {
 161                 t->callback.without_tstamp(card, RCODE_CANCELLED, NULL, 0, t->callback_data);
 162         } else {
 163                 t->callback.with_tstamp(card, RCODE_CANCELLED, t->packet.timestamp,
 164                                         t->split_timeout_cycle, NULL, 0, t->callback_data);
 165         }
 166 }
 167
 168 static void start_split_transaction_timeout(struct fw_transaction *t,
 169                                             struct fw_card *card)
 170 {
 171         unsigned long flags;
 172
 173         spin_lock_irqsave(&card->lock, flags);
 174
 175         if (list_empty(&t->link) || WARN_ON(t->is_split_transaction)) {
 176                 spin_unlock_irqrestore(&card->lock, flags);
 177                 return;
 178         }
 179
 180         t->is_split_transaction = true;
 181         mod_timer(&t->split_timeout_timer,
 182                   jiffies + card->split_timeout_jiffies);
 183
 184         spin_unlock_irqrestore(&card->lock, flags);
 185 }
 186
 187 static u32 compute_split_timeout_timestamp(struct fw_card *card, u32 request_timestamp);
 188
 189 static void transmit_complete_callback(struct fw_packet *packet,
 190                                        struct fw_card *card, int status)
 191 {
 192         struct fw_transaction *t =
 193             container_of(packet, struct fw_transaction, packet);
 194
 195         switch (status) {
 196         case ACK_COMPLETE:
 197                 close_transaction(t, card, RCODE_COMPLETE, packet->timestamp);
 198                 break;
 199         case ACK_PENDING:
 200         {
 201                 t->split_timeout_cycle =
 202                         compute_split_timeout_timestamp(card, packet->timestamp) & 0xffff;
 203                 start_split_transaction_timeout(t, card);
 204                 break;
 205         }
 206         case ACK_BUSY_X:
 207         case ACK_BUSY_A:
 208         case ACK_BUSY_B:
 209                 close_transaction(t, card, RCODE_BUSY, packet->timestamp);
 210                 break;
 211         case ACK_DATA_ERROR:
 212                 close_transaction(t, card, RCODE_DATA_ERROR, packet->timestamp);
 213                 break;
 214         case ACK_TYPE_ERROR:
 215                 close_transaction(t, card, RCODE_TYPE_ERROR, packet->timestamp);
 216                 break;
 217         default:
 218                 /*
 219                  * In this case the ack is really a juju specific
 220                  * rcode, so just forward that to the callback.
 221                  */
 222                 close_transaction(t, card, status, packet->timestamp);
 223                 break;
 224         }
 225 }
 226
 227 static void fw_fill_request(struct fw_packet *packet, int tcode, int tlabel,
 228                 int destination_id, int source_id, int generation, int speed,
 229                 unsigned long long offset, void *payload, size_t length)
 230 {
 231         int ext_tcode;
 232
 233         if (tcode == TCODE_STREAM_DATA) {
 234                 packet->header[0] =
 235                         HEADER_DATA_LENGTH(length) |
 236                         destination_id |
 237                         HEADER_TCODE(TCODE_STREAM_DATA);
 238                 packet->header_length = 4;
 239                 packet->payload = payload;
 240                 packet->payload_length = length;
 241
 242                 goto common;
 243         }
 244
 245         if (tcode > 0x10) {
 246                 ext_tcode = tcode & ~0x10;
 247                 tcode = TCODE_LOCK_REQUEST;
 248         } else
 249                 ext_tcode = 0;
 250
 251         packet->header[0] =
 252                 HEADER_RETRY(RETRY_X) |
 253                 HEADER_TLABEL(tlabel) |
 254                 HEADER_TCODE(tcode) |
 255                 HEADER_DESTINATION(destination_id);
 256         packet->header[1] =
 257                 HEADER_OFFSET_HIGH(offset >> 32) | HEADER_SOURCE(source_id);
 258         packet->header[2] =
 259                 offset;
 260
 261         switch (tcode) {
 262         case TCODE_WRITE_QUADLET_REQUEST:
 263                 packet->header[3] = *(u32 *)payload;
 264                 packet->header_length = 16;
 265                 packet->payload_length = 0;
 266                 break;
 267
 268         case TCODE_LOCK_REQUEST:
 269         case TCODE_WRITE_BLOCK_REQUEST:
 270                 packet->header[3] =
 271                         HEADER_DATA_LENGTH(length) |
 272                         HEADER_EXTENDED_TCODE(ext_tcode);
 273                 packet->header_length = 16;
 274                 packet->payload = payload;
 275                 packet->payload_length = length;
 276                 break;
 277
 278         case TCODE_READ_QUADLET_REQUEST:
 279                 packet->header_length = 12;
 280                 packet->payload_length = 0;
 281                 break;
 282
 283         case TCODE_READ_BLOCK_REQUEST:
 284                 packet->header[3] =
 285                         HEADER_DATA_LENGTH(length) |
 286                         HEADER_EXTENDED_TCODE(ext_tcode);
 287                 packet->header_length = 16;
 288                 packet->payload_length = 0;
 289                 break;
 290
 291         default:
 292                 WARN(1, "wrong tcode %d\n", tcode);
 293         }
 294  common:
 295         packet->speed = speed;
 296         packet->generation = generation;
 297         packet->ack = 0;
 298         packet->payload_mapped = false;
 299 }
 300
 301 static int allocate_tlabel(struct fw_card *card)
 302 {
 303         int tlabel;
 304
 305         tlabel = card->current_tlabel;
 306         while (card->tlabel_mask & (1ULL << tlabel)) {
 307                 tlabel = (tlabel + 1) & 0x3f;
 308                 if (tlabel == card->current_tlabel)
 309                         return -EBUSY;
 310         }
 311
 312         card->current_tlabel = (tlabel + 1) & 0x3f;
 313         card->tlabel_mask |= 1ULL << tlabel;
 314
 315         return tlabel;
 316 }
 317
 318 /**
 319  * __fw_send_request() - submit a request packet for transmission to generate callback for response
 320  *                       subaction with or without time stamp.
 321  * @card:               interface to send the request at
 322  * @t:                  transaction instance to which the request belongs
 323  * @tcode:              transaction code
 324  * @destination_id:     destination node ID, consisting of bus_ID and phy_ID
 325  * @generation:         bus generation in which request and response are valid
 326  * @speed:              transmission speed
 327  * @offset:             48bit wide offset into destination's address space
 328  * @payload:            data payload for the request subaction
 329  * @length:             length of the payload, in bytes
 330  * @callback:           union of two functions whether to receive time stamp or not for response
 331  *                      subaction.
 332  * @with_tstamp:        Whether to receive time stamp or not for response subaction.
 333  * @callback_data:      data to be passed to the transaction completion callback
 334  *
 335  * Submit a request packet into the asynchronous request transmission queue.
 336  * Can be called from atomic context.  If you prefer a blocking API, use
 337  * fw_run_transaction() in a context that can sleep.
 338  *
 339  * In case of lock requests, specify one of the firewire-core specific %TCODE_
 340  * constants instead of %TCODE_LOCK_REQUEST in @tcode.
 341  *
 342  * Make sure that the value in @destination_id is not older than the one in
 343  * @generation.  Otherwise the request is in danger to be sent to a wrong node.
 344  *
 345  * In case of asynchronous stream packets i.e. %TCODE_STREAM_DATA, the caller
 346  * needs to synthesize @destination_id with fw_stream_packet_destination_id().
 347  * It will contain tag, channel, and sy data instead of a node ID then.
 348  *
 349  * The payload buffer at @data is going to be DMA-mapped except in case of
 350  * @length <= 8 or of local (loopback) requests.  Hence make sure that the
 351  * buffer complies with the restrictions of the streaming DMA mapping API.
 352  * @payload must not be freed before the @callback is called.
 353  *
 354  * In case of request types without payload, @data is NULL and @length is 0.
 355  *
 356  * After the transaction is completed successfully or unsuccessfully, the
 357  * @callback will be called.  Among its parameters is the response code which
 358  * is either one of the rcodes per IEEE 1394 or, in case of internal errors,
 359  * the firewire-core specific %RCODE_SEND_ERROR.  The other firewire-core
 360  * specific rcodes (%RCODE_CANCELLED, %RCODE_BUSY, %RCODE_GENERATION,
 361  * %RCODE_NO_ACK) denote transaction timeout, busy responder, stale request
 362  * generation, or missing ACK respectively.
 363  *
 364  * Note some timing corner cases:  fw_send_request() may complete much earlier
 365  * than when the request packet actually hits the wire.  On the other hand,
 366  * transaction completion and hence execution of @callback may happen even
 367  * before fw_send_request() returns.
 368  */
 369 void __fw_send_request(struct fw_card *card, struct fw_transaction *t, int tcode,
 370                 int destination_id, int generation, int speed, unsigned long long offset,
 371                 void *payload, size_t length, union fw_transaction_callback callback,
 372                 bool with_tstamp, void *callback_data)
 373 {
 374         unsigned long flags;
 375         int tlabel;
 376
 377         /*
 378          * Allocate tlabel from the bitmap and put the transaction on
 379          * the list while holding the card spinlock.
 380          */
 381
 382         spin_lock_irqsave(&card->lock, flags);
 383
 384         tlabel = allocate_tlabel(card);
 385         if (tlabel < 0) {
 386                 spin_unlock_irqrestore(&card->lock, flags);
 387                 if (!with_tstamp) {
 388                         callback.without_tstamp(card, RCODE_SEND_ERROR, NULL, 0, callback_data);
 389                 } else {
 390                         // Timestamping on behalf of hardware.
 391                         u32 curr_cycle_time = 0;
 392                         u32 tstamp;
 393
 394                         (void)fw_card_read_cycle_time(card, &curr_cycle_time);
 395                         tstamp = cycle_time_to_ohci_tstamp(curr_cycle_time);
 396
 397                         callback.with_tstamp(card, RCODE_SEND_ERROR, tstamp, tstamp, NULL, 0,
 398                                              callback_data);
 399                 }
 400                 return;
 401         }
 402
 403         t->node_id = destination_id;
 404         t->tlabel = tlabel;
 405         t->card = card;
 406         t->is_split_transaction = false;
 407         timer_setup(&t->split_timeout_timer, split_transaction_timeout_callback, 0);
 408         t->callback = callback;
 409         t->with_tstamp = with_tstamp;
 410         t->callback_data = callback_data;
 411
 412         fw_fill_request(&t->packet, tcode, t->tlabel, destination_id, card->node_id, generation,
 413                         speed, offset, payload, length);
 414         t->packet.callback = transmit_complete_callback;
 415
 416         list_add_tail(&t->link, &card->transaction_list);
 417
 418         spin_unlock_irqrestore(&card->lock, flags);
 419
 420         card->driver->send_request(card, &t->packet);
 421 }
 422 EXPORT_SYMBOL_GPL(__fw_send_request);
 423
 424 struct transaction_callback_data {
 425         struct completion done;
 426         void *payload;
 427         int rcode;
 428 };
 429
 430 static void transaction_callback(struct fw_card *card, int rcode,
 431                                  void *payload, size_t length, void *data)
 432 {
 433         struct transaction_callback_data *d = data;
 434
 435         if (rcode == RCODE_COMPLETE)
 436                 memcpy(d->payload, payload, length);
 437         d->rcode = rcode;
 438         complete(&d->done);
 439 }
 440
 441 /**
 442  * fw_run_transaction() - send request and sleep until transaction is completed
 443  * @card:               card interface for this request
 444  * @tcode:              transaction code
 445  * @destination_id:     destination node ID, consisting of bus_ID and phy_ID
 446  * @generation:         bus generation in which request and response are valid
 447  * @speed:              transmission speed
 448  * @offset:             48bit wide offset into destination's address space
 449  * @payload:            data payload for the request subaction
 450  * @length:             length of the payload, in bytes
 451  *
 452  * Returns the RCODE.  See fw_send_request() for parameter documentation.
 453  * Unlike fw_send_request(), @data points to the payload of the request or/and
 454  * to the payload of the response.  DMA mapping restrictions apply to outbound
 455  * request payloads of >= 8 bytes but not to inbound response payloads.
 456  */
 457 int fw_run_transaction(struct fw_card *card, int tcode, int destination_id,
 458                        int generation, int speed, unsigned long long offset,
 459                        void *payload, size_t length)
 460 {
 461         struct transaction_callback_data d;
 462         struct fw_transaction t;
 463
 464         timer_setup_on_stack(&t.split_timeout_timer, NULL, 0);
 465         init_completion(&d.done);
 466         d.payload = payload;
 467         fw_send_request(card, &t, tcode, destination_id, generation, speed,
 468                         offset, payload, length, transaction_callback, &d);
 469         wait_for_completion(&d.done);
 470         destroy_timer_on_stack(&t.split_timeout_timer);
 471
 472         return d.rcode;
 473 }
 474 EXPORT_SYMBOL(fw_run_transaction);
 475
 476 static DEFINE_MUTEX(phy_config_mutex);
 477 static DECLARE_COMPLETION(phy_config_done);
 478
 479 static void transmit_phy_packet_callback(struct fw_packet *packet,
 480                                          struct fw_card *card, int status)
 481 {
 482         complete(&phy_config_done);
 483 }
 484
 485 static struct fw_packet phy_config_packet = {
 486         .header_length  = 12,
 487         .header[0]      = TCODE_LINK_INTERNAL << 4,
 488         .payload_length = 0,
 489         .speed          = SCODE_100,
 490         .callback       = transmit_phy_packet_callback,
 491 };
 492
 493 void fw_send_phy_config(struct fw_card *card,
 494                         int node_id, int generation, int gap_count)
 495 {
 496         long timeout = DIV_ROUND_UP(HZ, 10);
 497         u32 data = PHY_IDENTIFIER(PHY_PACKET_CONFIG);
 498
 499         if (node_id != FW_PHY_CONFIG_NO_NODE_ID)
 500                 data |= PHY_CONFIG_ROOT_ID(node_id);
 501
 502         if (gap_count == FW_PHY_CONFIG_CURRENT_GAP_COUNT) {
 503                 gap_count = card->driver->read_phy_reg(card, 1);
 504                 if (gap_count < 0)
 505                         return;
 506
 507                 gap_count &= 63;
 508                 if (gap_count == 63)
 509                         return;
 510         }
 511         data |= PHY_CONFIG_GAP_COUNT(gap_count);
 512
 513         mutex_lock(&phy_config_mutex);
 514
 515         phy_config_packet.header[1] = data;
 516         phy_config_packet.header[2] = ~data;
 517         phy_config_packet.generation = generation;
 518         reinit_completion(&phy_config_done);
 519
 520         card->driver->send_request(card, &phy_config_packet);
 521         wait_for_completion_timeout(&phy_config_done, timeout);
 522
 523         mutex_unlock(&phy_config_mutex);
 524 }
 525
 526 static struct fw_address_handler *lookup_overlapping_address_handler(
 527         struct list_head *list, unsigned long long offset, size_t length)
 528 {
 529         struct fw_address_handler *handler;
 530
 531         list_for_each_entry_rcu(handler, list, link) {
 532                 if (handler->offset < offset + length &&
 533                     offset < handler->offset + handler->length)
 534                         return handler;
 535         }
 536
 537         return NULL;
 538 }
 539
 540 static bool is_enclosing_handler(struct fw_address_handler *handler,
 541                                  unsigned long long offset, size_t length)
 542 {
 543         return handler->offset <= offset &&
 544                 offset + length <= handler->offset + handler->length;
 545 }
 546
 547 static struct fw_address_handler *lookup_enclosing_address_handler(
 548         struct list_head *list, unsigned long long offset, size_t length)
 549 {
 550         struct fw_address_handler *handler;
 551
 552         list_for_each_entry_rcu(handler, list, link) {
 553                 if (is_enclosing_handler(handler, offset, length))
 554                         return handler;
 555         }
 556
 557         return NULL;
 558 }
 559
 560 static DEFINE_SPINLOCK(address_handler_list_lock);
 561 static LIST_HEAD(address_handler_list);
 562
 563 const struct fw_address_region fw_high_memory_region =
 564         { .start = FW_MAX_PHYSICAL_RANGE, .end = 0xffffe0000000ULL, };
 565 EXPORT_SYMBOL(fw_high_memory_region);
 566
 567 static const struct fw_address_region low_memory_region =
 568         { .start = 0x000000000000ULL, .end = FW_MAX_PHYSICAL_RANGE, };
 569
 570 #if 0
 571 const struct fw_address_region fw_private_region =
 572         { .start = 0xffffe0000000ULL, .end = 0xfffff0000000ULL,  };
 573 const struct fw_address_region fw_csr_region =
 574         { .start = CSR_REGISTER_BASE,
 575           .end   = CSR_REGISTER_BASE | CSR_CONFIG_ROM_END,  };
 576 const struct fw_address_region fw_unit_space_region =
 577         { .start = 0xfffff0000900ULL, .end = 0x1000000000000ULL, };
 578 #endif  /*  0  */
 579
 580 /**
 581  * fw_core_add_address_handler() - register for incoming requests
 582  * @handler:    callback
 583  * @region:     region in the IEEE 1212 node space address range
 584  *
 585  * region->start, ->end, and handler->length have to be quadlet-aligned.
 586  *
 587  * When a request is received that falls within the specified address range,
 588  * the specified callback is invoked.  The parameters passed to the callback
 589  * give the details of the particular request.
 590  *
 591  * To be called in process context.
 592  * Return value:  0 on success, non-zero otherwise.
 593  *
 594  * The start offset of the handler's address region is determined by
 595  * fw_core_add_address_handler() and is returned in handler->offset.
 596  *
 597  * Address allocations are exclusive, except for the FCP registers.
 598  */
 599 int fw_core_add_address_handler(struct fw_address_handler *handler,
 600                                 const struct fw_address_region *region)
 601 {
 602         struct fw_address_handler *other;
 603         int ret = -EBUSY;
 604
 605         if (region->start & 0xffff000000000003ULL ||
 606             region->start >= region->end ||
 607             region->end   > 0x0001000000000000ULL ||
 608             handler->length & 3 ||
 609             handler->length == 0)
 610                 return -EINVAL;
 611
 612         spin_lock(&address_handler_list_lock);
 613
 614         handler->offset = region->start;
 615         while (handler->offset + handler->length <= region->end) {
 616                 if (is_in_fcp_region(handler->offset, handler->length))
 617                         other = NULL;
 618                 else
 619                         other = lookup_overlapping_address_handler
 620                                         (&address_handler_list,
 621                                          handler->offset, handler->length);
 622                 if (other != NULL) {
 623                         handler->offset += other->length;
 624                 } else {
 625                         list_add_tail_rcu(&handler->link, &address_handler_list);
 626                         ret = 0;
 627                         break;
 628                 }
 629         }
 630
 631         spin_unlock(&address_handler_list_lock);
 632
 633         return ret;
 634 }
 635 EXPORT_SYMBOL(fw_core_add_address_handler);
 636
 637 /**
 638  * fw_core_remove_address_handler() - unregister an address handler
 639  * @handler: callback
 640  *
 641  * To be called in process context.
 642  *
 643  * When fw_core_remove_address_handler() returns, @handler->callback() is
 644  * guaranteed to not run on any CPU anymore.
 645  */
 646 void fw_core_remove_address_handler(struct fw_address_handler *handler)
 647 {
 648         spin_lock(&address_handler_list_lock);
 649         list_del_rcu(&handler->link);
 650         spin_unlock(&address_handler_list_lock);
 651         synchronize_rcu();
 652 }
 653 EXPORT_SYMBOL(fw_core_remove_address_handler);
 654
 655 struct fw_request {
 656         struct kref kref;
 657         struct fw_packet response;
 658         u32 request_header[4];
 659         int ack;
 660         u32 timestamp;
 661         u32 length;
 662         u32 data[];
 663 };
 664
 665 void fw_request_get(struct fw_request *request)
 666 {
 667         kref_get(&request->kref);
 668 }
 669
 670 static void release_request(struct kref *kref)
 671 {
 672         struct fw_request *request = container_of(kref, struct fw_request, kref);
 673
 674         kfree(request);
 675 }
 676
 677 void fw_request_put(struct fw_request *request)
 678 {
 679         kref_put(&request->kref, release_request);
 680 }
 681
 682 static void free_response_callback(struct fw_packet *packet,
 683                                    struct fw_card *card, int status)
 684 {
 685         struct fw_request *request = container_of(packet, struct fw_request, response);
 686
 687         // Decrease the reference count since not at in-flight.
 688         fw_request_put(request);
 689
 690         // Decrease the reference count to release the object.
 691         fw_request_put(request);
 692 }
 693
 694 int fw_get_response_length(struct fw_request *r)
 695 {
 696         int tcode, ext_tcode, data_length;
 697
 698         tcode = HEADER_GET_TCODE(r->request_header[0]);
 699
 700         switch (tcode) {
 701         case TCODE_WRITE_QUADLET_REQUEST:
 702         case TCODE_WRITE_BLOCK_REQUEST:
 703                 return 0;
 704
 705         case TCODE_READ_QUADLET_REQUEST:
 706                 return 4;
 707
 708         case TCODE_READ_BLOCK_REQUEST:
 709                 data_length = HEADER_GET_DATA_LENGTH(r->request_header[3]);
 710                 return data_length;
 711
 712         case TCODE_LOCK_REQUEST:
 713                 ext_tcode = HEADER_GET_EXTENDED_TCODE(r->request_header[3]);
 714                 data_length = HEADER_GET_DATA_LENGTH(r->request_header[3]);
 715                 switch (ext_tcode) {
 716                 case EXTCODE_FETCH_ADD:
 717                 case EXTCODE_LITTLE_ADD:
 718                         return data_length;
 719                 default:
 720                         return data_length / 2;
 721                 }
 722
 723         default:
 724                 WARN(1, "wrong tcode %d\n", tcode);
 725                 return 0;
 726         }
 727 }
 728
 729 void fw_fill_response(struct fw_packet *response, u32 *request_header,
 730                       int rcode, void *payload, size_t length)
 731 {
 732         int tcode, tlabel, extended_tcode, source, destination;
 733
 734         tcode          = HEADER_GET_TCODE(request_header[0]);
 735         tlabel         = HEADER_GET_TLABEL(request_header[0]);
 736         source         = HEADER_GET_DESTINATION(request_header[0]);
 737         destination    = HEADER_GET_SOURCE(request_header[1]);
 738         extended_tcode = HEADER_GET_EXTENDED_TCODE(request_header[3]);
 739
 740         response->header[0] =
 741                 HEADER_RETRY(RETRY_1) |
 742                 HEADER_TLABEL(tlabel) |
 743                 HEADER_DESTINATION(destination);
 744         response->header[1] =
 745                 HEADER_SOURCE(source) |
 746                 HEADER_RCODE(rcode);
 747         response->header[2] = 0;
 748
 749         switch (tcode) {
 750         case TCODE_WRITE_QUADLET_REQUEST:
 751         case TCODE_WRITE_BLOCK_REQUEST:
 752                 response->header[0] |= HEADER_TCODE(TCODE_WRITE_RESPONSE);
 753                 response->header_length = 12;
 754                 response->payload_length = 0;
 755                 break;
 756
 757         case TCODE_READ_QUADLET_REQUEST:
 758                 response->header[0] |=
 759                         HEADER_TCODE(TCODE_READ_QUADLET_RESPONSE);
 760                 if (payload != NULL)
 761                         response->header[3] = *(u32 *)payload;
 762                 else
 763                         response->header[3] = 0;
 764                 response->header_length = 16;
 765                 response->payload_length = 0;
 766                 break;
 767
 768         case TCODE_READ_BLOCK_REQUEST:
 769         case TCODE_LOCK_REQUEST:
 770                 response->header[0] |= HEADER_TCODE(tcode + 2);
 771                 response->header[3] =
 772                         HEADER_DATA_LENGTH(length) |
 773                         HEADER_EXTENDED_TCODE(extended_tcode);
 774                 response->header_length = 16;
 775                 response->payload = payload;
 776                 response->payload_length = length;
 777                 break;
 778
 779         default:
 780                 WARN(1, "wrong tcode %d\n", tcode);
 781         }
 782
 783         response->payload_mapped = false;
 784 }
 785 EXPORT_SYMBOL(fw_fill_response);
 786
 787 static u32 compute_split_timeout_timestamp(struct fw_card *card,
 788                                            u32 request_timestamp)
 789 {
 790         unsigned int cycles;
 791         u32 timestamp;
 792
 793         cycles = card->split_timeout_cycles;
 794         cycles += request_timestamp & 0x1fff;
 795
 796         timestamp = request_timestamp & ~0x1fff;
 797         timestamp += (cycles / 8000) << 13;
 798         timestamp |= cycles % 8000;
 799
 800         return timestamp;
 801 }
 802
 803 static struct fw_request *allocate_request(struct fw_card *card,
 804                                            struct fw_packet *p)
 805 {
 806         struct fw_request *request;
 807         u32 *data, length;
 808         int request_tcode;
 809
 810         request_tcode = HEADER_GET_TCODE(p->header[0]);
 811         switch (request_tcode) {
 812         case TCODE_WRITE_QUADLET_REQUEST:
 813                 data = &p->header[3];
 814                 length = 4;
 815                 break;
 816
 817         case TCODE_WRITE_BLOCK_REQUEST:
 818         case TCODE_LOCK_REQUEST:
 819                 data = p->payload;
 820                 length = HEADER_GET_DATA_LENGTH(p->header[3]);
 821                 break;
 822
 823         case TCODE_READ_QUADLET_REQUEST:
 824                 data = NULL;
 825                 length = 4;
 826                 break;
 827
 828         case TCODE_READ_BLOCK_REQUEST:
 829                 data = NULL;
 830                 length = HEADER_GET_DATA_LENGTH(p->header[3]);
 831                 break;
 832
 833         default:
 834                 fw_notice(card, "ERROR - corrupt request received - %08x %08x %08x\n",
 835                          p->header[0], p->header[1], p->header[2]);
 836                 return NULL;
 837         }
 838
 839         request = kmalloc(sizeof(*request) + length, GFP_ATOMIC);
 840         if (request == NULL)
 841                 return NULL;
 842         kref_init(&request->kref);
 843
 844         request->response.speed = p->speed;
 845         request->response.timestamp =
 846                         compute_split_timeout_timestamp(card, p->timestamp);
 847         request->response.generation = p->generation;
 848         request->response.ack = 0;
 849         request->response.callback = free_response_callback;
 850         request->ack = p->ack;
 851         request->timestamp = p->timestamp;
 852         request->length = length;
 853         if (data)
 854                 memcpy(request->data, data, length);
 855
 856         memcpy(request->request_header, p->header, sizeof(p->header));
 857
 858         return request;
 859 }
 860
 861 /**
 862  * fw_send_response: - send response packet for asynchronous transaction.
 863  * @card:       interface to send the response at.
 864  * @request:    firewire request data for the transaction.
 865  * @rcode:      response code to send.
 866  *
 867  * Submit a response packet into the asynchronous response transmission queue. The @request
 868  * is going to be released when the transmission successfully finishes later.
 869  */
 870 void fw_send_response(struct fw_card *card,
 871                       struct fw_request *request, int rcode)
 872 {
 873         /* unified transaction or broadcast transaction: don't respond */
 874         if (request->ack != ACK_PENDING ||
 875             HEADER_DESTINATION_IS_BROADCAST(request->request_header[0])) {
 876                 fw_request_put(request);
 877                 return;
 878         }
 879
 880         if (rcode == RCODE_COMPLETE)
 881                 fw_fill_response(&request->response, request->request_header,
 882                                  rcode, request->data,
 883                                  fw_get_response_length(request));
 884         else
 885                 fw_fill_response(&request->response, request->request_header,
 886                                  rcode, NULL, 0);
 887
 888         // Increase the reference count so that the object is kept during in-flight.
 889         fw_request_get(request);
 890
 891         card->driver->send_response(card, &request->response);
 892 }
 893 EXPORT_SYMBOL(fw_send_response);
 894
 895 /**
 896  * fw_get_request_speed() - returns speed at which the @request was received
 897  * @request: firewire request data
 898  */
 899 int fw_get_request_speed(struct fw_request *request)
 900 {
 901         return request->response.speed;
 902 }
 903 EXPORT_SYMBOL(fw_get_request_speed);
 904
 905 /**
 906  * fw_request_get_timestamp: Get timestamp of the request.
 907  * @request: The opaque pointer to request structure.
 908  *
 909  * Get timestamp when 1394 OHCI controller receives the asynchronous request subaction. The
 910  * timestamp consists of the low order 3 bits of second field and the full 13 bits of count
 911  * field of isochronous cycle time register.
 912  *
 913  * Returns: timestamp of the request.
 914  */
 915 u32 fw_request_get_timestamp(const struct fw_request *request)
 916 {
 917         return request->timestamp;
 918 }
 919 EXPORT_SYMBOL_GPL(fw_request_get_timestamp);
 920
 921 static void handle_exclusive_region_request(struct fw_card *card,
 922                                             struct fw_packet *p,
 923                                             struct fw_request *request,
 924                                             unsigned long long offset)
 925 {
 926         struct fw_address_handler *handler;
 927         int tcode, destination, source;
 928
 929         destination = HEADER_GET_DESTINATION(p->header[0]);
 930         source      = HEADER_GET_SOURCE(p->header[1]);
 931         tcode       = HEADER_GET_TCODE(p->header[0]);
 932         if (tcode == TCODE_LOCK_REQUEST)
 933                 tcode = 0x10 + HEADER_GET_EXTENDED_TCODE(p->header[3]);
 934
 935         rcu_read_lock();
 936         handler = lookup_enclosing_address_handler(&address_handler_list,
 937                                                    offset, request->length);
 938         if (handler)
 939                 handler->address_callback(card, request,
 940                                           tcode, destination, source,
 941                                           p->generation, offset,
 942                                           request->data, request->length,
 943                                           handler->callback_data);
 944         rcu_read_unlock();
 945
 946         if (!handler)
 947                 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
 948 }
 949
 950 static void handle_fcp_region_request(struct fw_card *card,
 951                                       struct fw_packet *p,
 952                                       struct fw_request *request,
 953                                       unsigned long long offset)
 954 {
 955         struct fw_address_handler *handler;
 956         int tcode, destination, source;
 957
 958         if ((offset != (CSR_REGISTER_BASE | CSR_FCP_COMMAND) &&
 959              offset != (CSR_REGISTER_BASE | CSR_FCP_RESPONSE)) ||
 960             request->length > 0x200) {
 961                 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
 962
 963                 return;
 964         }
 965
 966         tcode       = HEADER_GET_TCODE(p->header[0]);
 967         destination = HEADER_GET_DESTINATION(p->header[0]);
 968         source      = HEADER_GET_SOURCE(p->header[1]);
 969
 970         if (tcode != TCODE_WRITE_QUADLET_REQUEST &&
 971             tcode != TCODE_WRITE_BLOCK_REQUEST) {
 972                 fw_send_response(card, request, RCODE_TYPE_ERROR);
 973
 974                 return;
 975         }
 976
 977         rcu_read_lock();
 978         list_for_each_entry_rcu(handler, &address_handler_list, link) {
 979                 if (is_enclosing_handler(handler, offset, request->length))
 980                         handler->address_callback(card, request, tcode,
 981                                                   destination, source,
 982                                                   p->generation, offset,
 983                                                   request->data,
 984                                                   request->length,
 985                                                   handler->callback_data);
 986         }
 987         rcu_read_unlock();
 988
 989         fw_send_response(card, request, RCODE_COMPLETE);
 990 }
 991
 992 void fw_core_handle_request(struct fw_card *card, struct fw_packet *p)
 993 {
 994         struct fw_request *request;
 995         unsigned long long offset;
 996
 997         if (p->ack != ACK_PENDING && p->ack != ACK_COMPLETE)
 998                 return;
 999
1000         if (TCODE_IS_LINK_INTERNAL(HEADER_GET_TCODE(p->header[0]))) {
1001                 fw_cdev_handle_phy_packet(card, p);
1002                 return;
1003         }
1004
1005         request = allocate_request(card, p);
1006         if (request == NULL) {
1007                 /* FIXME: send statically allocated busy packet. */
1008                 return;
1009         }
1010
1011         offset = ((u64)HEADER_GET_OFFSET_HIGH(p->header[1]) << 32) |
1012                 p->header[2];
1013
1014         if (!is_in_fcp_region(offset, request->length))
1015                 handle_exclusive_region_request(card, p, request, offset);
1016         else
1017                 handle_fcp_region_request(card, p, request, offset);
1018
1019 }
1020 EXPORT_SYMBOL(fw_core_handle_request);
1021
1022 void fw_core_handle_response(struct fw_card *card, struct fw_packet *p)
1023 {
1024         struct fw_transaction *t = NULL, *iter;
1025         unsigned long flags;
1026         u32 *data;
1027         size_t data_length;
1028         int tcode, tlabel, source, rcode;
1029
1030         tcode   = HEADER_GET_TCODE(p->header[0]);
1031         tlabel  = HEADER_GET_TLABEL(p->header[0]);
1032         source  = HEADER_GET_SOURCE(p->header[1]);
1033         rcode   = HEADER_GET_RCODE(p->header[1]);
1034
1035         spin_lock_irqsave(&card->lock, flags);
1036         list_for_each_entry(iter, &card->transaction_list, link) {
1037                 if (iter->node_id == source && iter->tlabel == tlabel) {
1038                         if (!try_cancel_split_timeout(iter)) {
1039                                 spin_unlock_irqrestore(&card->lock, flags);
1040                                 goto timed_out;
1041                         }
1042                         list_del_init(&iter->link);
1043                         card->tlabel_mask &= ~(1ULL << iter->tlabel);
1044                         t = iter;
1045                         break;
1046                 }
1047         }
1048         spin_unlock_irqrestore(&card->lock, flags);
1049
1050         if (!t) {
1051  timed_out:
1052                 fw_notice(card, "unsolicited response (source %x, tlabel %x)\n",
1053                           source, tlabel);
1054                 return;
1055         }
1056
1057         /*
1058          * FIXME: sanity check packet, is length correct, does tcodes
1059          * and addresses match.
1060          */
1061
1062         switch (tcode) {
1063         case TCODE_READ_QUADLET_RESPONSE:
1064                 data = (u32 *) &p->header[3];
1065                 data_length = 4;
1066                 break;
1067
1068         case TCODE_WRITE_RESPONSE:
1069                 data = NULL;
1070                 data_length = 0;
1071                 break;
1072
1073         case TCODE_READ_BLOCK_RESPONSE:
1074         case TCODE_LOCK_RESPONSE:
1075                 data = p->payload;
1076                 data_length = HEADER_GET_DATA_LENGTH(p->header[3]);
1077                 break;
1078
1079         default:
1080                 /* Should never happen, this is just to shut up gcc. */
1081                 data = NULL;
1082                 data_length = 0;
1083                 break;
1084         }
1085
1086         /*
1087          * The response handler may be executed while the request handler
1088          * is still pending.  Cancel the request handler.
1089          */
1090         card->driver->cancel_packet(card, &t->packet);
1091
1092         if (!t->with_tstamp) {
1093                 t->callback.without_tstamp(card, rcode, data, data_length, t->callback_data);
1094         } else {
1095                 t->callback.with_tstamp(card, rcode, t->packet.timestamp, p->timestamp, data,
1096                                         data_length, t->callback_data);
1097         }
1098 }
1099 EXPORT_SYMBOL(fw_core_handle_response);
1100
1101 /**
1102  * fw_rcode_string - convert a firewire result code to an error description
1103  * @rcode: the result code
1104  */
1105 const char *fw_rcode_string(int rcode)
1106 {
1107         static const char *const names[] = {
1108                 [RCODE_COMPLETE]       = "no error",
1109                 [RCODE_CONFLICT_ERROR] = "conflict error",
1110                 [RCODE_DATA_ERROR]     = "data error",
1111                 [RCODE_TYPE_ERROR]     = "type error",
1112                 [RCODE_ADDRESS_ERROR]  = "address error",
1113                 [RCODE_SEND_ERROR]     = "send error",
1114                 [RCODE_CANCELLED]      = "timeout",
1115                 [RCODE_BUSY]           = "busy",
1116                 [RCODE_GENERATION]     = "bus reset",
1117                 [RCODE_NO_ACK]         = "no ack",
1118         };
1119
1120         if ((unsigned int)rcode < ARRAY_SIZE(names) && names[rcode])
1121                 return names[rcode];
1122         else
1123                 return "unknown";
1124 }
1125 EXPORT_SYMBOL(fw_rcode_string);
1126
1127 static const struct fw_address_region topology_map_region =
1128         { .start = CSR_REGISTER_BASE | CSR_TOPOLOGY_MAP,
1129           .end   = CSR_REGISTER_BASE | CSR_TOPOLOGY_MAP_END, };
1130
1131 static void handle_topology_map(struct fw_card *card, struct fw_request *request,
1132                 int tcode, int destination, int source, int generation,
1133                 unsigned long long offset, void *payload, size_t length,
1134                 void *callback_data)
1135 {
1136         int start;
1137
1138         if (!TCODE_IS_READ_REQUEST(tcode)) {
1139                 fw_send_response(card, request, RCODE_TYPE_ERROR);
1140                 return;
1141         }
1142
1143         if ((offset & 3) > 0 || (length & 3) > 0) {
1144                 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
1145                 return;
1146         }
1147
1148         start = (offset - topology_map_region.start) / 4;
1149         memcpy(payload, &card->topology_map[start], length);
1150
1151         fw_send_response(card, request, RCODE_COMPLETE);
1152 }
1153
1154 static struct fw_address_handler topology_map = {
1155         .length                 = 0x400,
1156         .address_callback       = handle_topology_map,
1157 };
1158
1159 static const struct fw_address_region registers_region =
1160         { .start = CSR_REGISTER_BASE,
1161           .end   = CSR_REGISTER_BASE | CSR_CONFIG_ROM, };
1162
1163 static void update_split_timeout(struct fw_card *card)
1164 {
1165         unsigned int cycles;
1166
1167         cycles = card->split_timeout_hi * 8000 + (card->split_timeout_lo >> 19);
1168
1169         /* minimum per IEEE 1394, maximum which doesn't overflow OHCI */
1170         cycles = clamp(cycles, 800u, 3u * 8000u);
1171
1172         card->split_timeout_cycles = cycles;
1173         card->split_timeout_jiffies = DIV_ROUND_UP(cycles * HZ, 8000);
1174 }
1175
1176 static void handle_registers(struct fw_card *card, struct fw_request *request,
1177                 int tcode, int destination, int source, int generation,
1178                 unsigned long long offset, void *payload, size_t length,
1179                 void *callback_data)
1180 {
1181         int reg = offset & ~CSR_REGISTER_BASE;
1182         __be32 *data = payload;
1183         int rcode = RCODE_COMPLETE;
1184         unsigned long flags;
1185
1186         switch (reg) {
1187         case CSR_PRIORITY_BUDGET:
1188                 if (!card->priority_budget_implemented) {
1189                         rcode = RCODE_ADDRESS_ERROR;
1190                         break;
1191                 }
1192                 fallthrough;
1193
1194         case CSR_NODE_IDS:
1195                 /*
1196                  * per IEEE 1394-2008 8.3.22.3, not IEEE 1394.1-2004 3.2.8
1197                  * and 9.6, but interoperable with IEEE 1394.1-2004 bridges
1198                  */
1199                 fallthrough;
1200
1201         case CSR_STATE_CLEAR:
1202         case CSR_STATE_SET:
1203         case CSR_CYCLE_TIME:
1204         case CSR_BUS_TIME:
1205         case CSR_BUSY_TIMEOUT:
1206                 if (tcode == TCODE_READ_QUADLET_REQUEST)
1207                         *data = cpu_to_be32(card->driver->read_csr(card, reg));
1208                 else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1209                         card->driver->write_csr(card, reg, be32_to_cpu(*data));
1210                 else
1211                         rcode = RCODE_TYPE_ERROR;
1212                 break;
1213
1214         case CSR_RESET_START:
1215                 if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1216                         card->driver->write_csr(card, CSR_STATE_CLEAR,
1217                                                 CSR_STATE_BIT_ABDICATE);
1218                 else
1219                         rcode = RCODE_TYPE_ERROR;
1220                 break;
1221
1222         case CSR_SPLIT_TIMEOUT_HI:
1223                 if (tcode == TCODE_READ_QUADLET_REQUEST) {
1224                         *data = cpu_to_be32(card->split_timeout_hi);
1225                 } else if (tcode == TCODE_WRITE_QUADLET_REQUEST) {
1226                         spin_lock_irqsave(&card->lock, flags);
1227                         card->split_timeout_hi = be32_to_cpu(*data) & 7;
1228                         update_split_timeout(card);
1229                         spin_unlock_irqrestore(&card->lock, flags);
1230                 } else {
1231                         rcode = RCODE_TYPE_ERROR;
1232                 }
1233                 break;
1234
1235         case CSR_SPLIT_TIMEOUT_LO:
1236                 if (tcode == TCODE_READ_QUADLET_REQUEST) {
1237                         *data = cpu_to_be32(card->split_timeout_lo);
1238                 } else if (tcode == TCODE_WRITE_QUADLET_REQUEST) {
1239                         spin_lock_irqsave(&card->lock, flags);
1240                         card->split_timeout_lo =
1241                                         be32_to_cpu(*data) & 0xfff80000;
1242                         update_split_timeout(card);
1243                         spin_unlock_irqrestore(&card->lock, flags);
1244                 } else {
1245                         rcode = RCODE_TYPE_ERROR;
1246                 }
1247                 break;
1248
1249         case CSR_MAINT_UTILITY:
1250                 if (tcode == TCODE_READ_QUADLET_REQUEST)
1251                         *data = card->maint_utility_register;
1252                 else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1253                         card->maint_utility_register = *data;
1254                 else
1255                         rcode = RCODE_TYPE_ERROR;
1256                 break;
1257
1258         case CSR_BROADCAST_CHANNEL:
1259                 if (tcode == TCODE_READ_QUADLET_REQUEST)
1260                         *data = cpu_to_be32(card->broadcast_channel);
1261                 else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
1262                         card->broadcast_channel =
1263                             (be32_to_cpu(*data) & BROADCAST_CHANNEL_VALID) |
1264                             BROADCAST_CHANNEL_INITIAL;
1265                 else
1266                         rcode = RCODE_TYPE_ERROR;
1267                 break;
1268
1269         case CSR_BUS_MANAGER_ID:
1270         case CSR_BANDWIDTH_AVAILABLE:
1271         case CSR_CHANNELS_AVAILABLE_HI:
1272         case CSR_CHANNELS_AVAILABLE_LO:
1273                 /*
1274                  * FIXME: these are handled by the OHCI hardware and
1275                  * the stack never sees these request. If we add
1276                  * support for a new type of controller that doesn't
1277                  * handle this in hardware we need to deal with these
1278                  * transactions.
1279                  */
1280                 BUG();
1281                 break;
1282
1283         default:
1284                 rcode = RCODE_ADDRESS_ERROR;
1285                 break;
1286         }
1287
1288         fw_send_response(card, request, rcode);
1289 }
1290
1291 static struct fw_address_handler registers = {
1292         .length                 = 0x400,
1293         .address_callback       = handle_registers,
1294 };
1295
1296 static void handle_low_memory(struct fw_card *card, struct fw_request *request,
1297                 int tcode, int destination, int source, int generation,
1298                 unsigned long long offset, void *payload, size_t length,
1299                 void *callback_data)
1300 {
1301         /*
1302          * This catches requests not handled by the physical DMA unit,
1303          * i.e., wrong transaction types or unauthorized source nodes.
1304          */
1305         fw_send_response(card, request, RCODE_TYPE_ERROR);
1306 }
1307
1308 static struct fw_address_handler low_memory = {
1309         .length                 = FW_MAX_PHYSICAL_RANGE,
1310         .address_callback       = handle_low_memory,
1311 };
1312
1313 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1314 MODULE_DESCRIPTION("Core IEEE1394 transaction logic");
1315 MODULE_LICENSE("GPL");
1316
1317 static const u32 vendor_textual_descriptor[] = {
1318         /* textual descriptor leaf () */
1319         0x00060000,
1320         0x00000000,
1321         0x00000000,
1322         0x4c696e75,             /* L i n u */
1323         0x78204669,             /* x   F i */
1324         0x72657769,             /* r e w i */
1325         0x72650000,             /* r e     */
1326 };
1327
1328 static const u32 model_textual_descriptor[] = {
1329         /* model descriptor leaf () */
1330         0x00030000,
1331         0x00000000,
1332         0x00000000,
1333         0x4a756a75,             /* J u j u */
1334 };
1335
1336 static struct fw_descriptor vendor_id_descriptor = {
1337         .length = ARRAY_SIZE(vendor_textual_descriptor),
1338         .immediate = 0x03001f11,
1339         .key = 0x81000000,
1340         .data = vendor_textual_descriptor,
1341 };
1342
1343 static struct fw_descriptor model_id_descriptor = {
1344         .length = ARRAY_SIZE(model_textual_descriptor),
1345         .immediate = 0x17023901,
1346         .key = 0x81000000,
1347         .data = model_textual_descriptor,
1348 };
1349
1350 static int __init fw_core_init(void)
1351 {
1352         int ret;
1353
1354         fw_workqueue = alloc_workqueue("firewire", WQ_MEM_RECLAIM, 0);
1355         if (!fw_workqueue)
1356                 return -ENOMEM;
1357
1358         ret = bus_register(&fw_bus_type);
1359         if (ret < 0) {
1360                 destroy_workqueue(fw_workqueue);
1361                 return ret;
1362         }
1363
1364         fw_cdev_major = register_chrdev(0, "firewire", &fw_device_ops);
1365         if (fw_cdev_major < 0) {
1366                 bus_unregister(&fw_bus_type);
1367                 destroy_workqueue(fw_workqueue);
1368                 return fw_cdev_major;
1369         }
1370
1371         fw_core_add_address_handler(&topology_map, &topology_map_region);
1372         fw_core_add_address_handler(&registers, &registers_region);
1373         fw_core_add_address_handler(&low_memory, &low_memory_region);
1374         fw_core_add_descriptor(&vendor_id_descriptor);
1375         fw_core_add_descriptor(&model_id_descriptor);
1376
1377         return 0;
1378 }
1379
1380 static void __exit fw_core_cleanup(void)
1381 {
1382         unregister_chrdev(fw_cdev_major, "firewire");
1383         bus_unregister(&fw_bus_type);
1384         destroy_workqueue(fw_workqueue);
1385         idr_destroy(&fw_device_idr);
1386 }
1387
1388 module_init(fw_core_init);
1389 module_exit(fw_core_cleanup);