drivers/firewire/fw-transaction.c

   1 /*                                              -*- c-basic-offset: 8 -*-
   2  *
   3  * fw-transaction.c - core IEEE1394 transaction logic
   4  *
   5  * Copyright (C) 2004-2006 Kristian Hoegsberg <krh@bitplanet.net>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software Foundation,
  19  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  20  */
  21
  22 #include <linux/kernel.h>
  23 #include <linux/module.h>
  24 #include <linux/init.h>
  25 #include <linux/interrupt.h>
  26 #include <linux/pci.h>
  27 #include <linux/delay.h>
  28 #include <linux/poll.h>
  29 #include <linux/list.h>
  30 #include <linux/kthread.h>
  31 #include <asm/uaccess.h>
  32 #include <asm/semaphore.h>
  33
  34 #include "fw-transaction.h"
  35 #include "fw-topology.h"
  36 #include "fw-device.h"
  37
  38 #define header_pri(pri)                 ((pri) << 0)
  39 #define header_tcode(tcode)             ((tcode) << 4)
  40 #define header_retry(retry)             ((retry) << 8)
  41 #define header_tlabel(tlabel)           ((tlabel) << 10)
  42 #define header_destination(destination) ((destination) << 16)
  43 #define header_source(source)           ((source) << 16)
  44 #define header_rcode(rcode)             ((rcode) << 12)
  45 #define header_offset_high(offset_high) ((offset_high) << 0)
  46 #define header_data_length(length)      ((length) << 16)
  47 #define header_extended_tcode(tcode)    ((tcode) << 0)
  48
  49 #define header_get_tcode(q)             (((q) >> 4) & 0x0f)
  50 #define header_get_tlabel(q)            (((q) >> 10) & 0x3f)
  51 #define header_get_rcode(q)             (((q) >> 4) & 0x0f)
  52 #define header_get_destination(q)       (((q) >> 16) & 0xffff)
  53 #define header_get_source(q)            (((q) >> 16) & 0xffff)
  54 #define header_get_offset_high(q)       (((q) >> 0) & 0xffff)
  55 #define header_get_data_length(q)       (((q) >> 16) & 0xffff)
  56 #define header_get_extended_tcode(q)    (((q) >> 0) & 0xffff)
  57
  58 #define phy_config_gap_count(gap_count) (((gap_count) << 16) | (1 << 22))
  59 #define phy_config_root_id(node_id)     (((node_id) << 24) | (1 << 23))
  60 #define phy_identifier(id)              ((id) << 30)
  61
  62 static void
  63 close_transaction(struct fw_transaction *t, struct fw_card *card, int rcode,
  64                   u32 * payload, size_t length)
  65 {
  66         unsigned long flags;
  67
  68         spin_lock_irqsave(&card->lock, flags);
  69         card->tlabel_mask &= ~(1 << t->tlabel);
  70         list_del(&t->link);
  71         spin_unlock_irqrestore(&card->lock, flags);
  72
  73         t->callback(card, rcode, payload, length, t->callback_data);
  74 }
  75
  76 static void
  77 transmit_complete_callback(struct fw_packet *packet,
  78                            struct fw_card *card, int status)
  79 {
  80         struct fw_transaction *t =
  81             container_of(packet, struct fw_transaction, packet);
  82
  83         switch (status) {
  84         case ACK_COMPLETE:
  85                 close_transaction(t, card, RCODE_COMPLETE, NULL, 0);
  86                 break;
  87         case ACK_PENDING:
  88                 t->timestamp = packet->timestamp;
  89                 break;
  90         case ACK_BUSY_X:
  91         case ACK_BUSY_A:
  92         case ACK_BUSY_B:
  93                 close_transaction(t, card, RCODE_BUSY, NULL, 0);
  94                 break;
  95         case ACK_DATA_ERROR:
  96         case ACK_TYPE_ERROR:
  97                 close_transaction(t, card, RCODE_SEND_ERROR, NULL, 0);
  98                 break;
  99         default:
 100                 /* FIXME: In this case, status is a negative errno,
 101                  * corresponding to an OHCI specific transmit error
 102                  * code.  We should map that to an RCODE instead of
 103                  * just the generic RCODE_SEND_ERROR. */
 104                 close_transaction(t, card, RCODE_SEND_ERROR, NULL, 0);
 105                 break;
 106         }
 107 }
 108
 109 void
 110 fw_fill_packet(struct fw_packet *packet, int tcode, int tlabel,
 111                int node_id, int generation, int speed,
 112                unsigned long long offset, void *payload, size_t length)
 113 {
 114         int ext_tcode;
 115
 116         if (tcode > 0x10) {
 117                 ext_tcode = tcode - 0x10;
 118                 tcode = TCODE_LOCK_REQUEST;
 119         } else
 120                 ext_tcode = 0;
 121
 122         packet->header[0] =
 123                 header_retry(RETRY_X) |
 124                 header_tlabel(tlabel) |
 125                 header_tcode(tcode) |
 126                 header_destination(node_id | LOCAL_BUS);
 127         packet->header[1] =
 128                 header_offset_high(offset >> 32) | header_source(0);
 129         packet->header[2] =
 130                 offset;
 131
 132         switch (tcode) {
 133         case TCODE_WRITE_QUADLET_REQUEST:
 134                 packet->header[3] = *(u32 *)payload;
 135                 packet->header_length = 16;
 136                 packet->payload_length = 0;
 137                 break;
 138
 139         case TCODE_LOCK_REQUEST:
 140         case TCODE_WRITE_BLOCK_REQUEST:
 141                 packet->header[3] =
 142                         header_data_length(length) |
 143                         header_extended_tcode(ext_tcode);
 144                 packet->header_length = 16;
 145                 packet->payload = payload;
 146                 packet->payload_length = length;
 147                 break;
 148
 149         case TCODE_READ_QUADLET_REQUEST:
 150                 packet->header_length = 12;
 151                 packet->payload_length = 0;
 152                 break;
 153
 154         case TCODE_READ_BLOCK_REQUEST:
 155                 packet->header[3] =
 156                         header_data_length(length) |
 157                         header_extended_tcode(ext_tcode);
 158                 packet->header_length = 16;
 159                 packet->payload_length = 0;
 160                 break;
 161         }
 162
 163         packet->speed = speed;
 164         packet->generation = generation;
 165 }
 166
 167 /**
 168  * This function provides low-level access to the IEEE1394 transaction
 169  * logic.  Most C programs would use either fw_read(), fw_write() or
 170  * fw_lock() instead - those function are convenience wrappers for
 171  * this function.  The fw_send_request() function is primarily
 172  * provided as a flexible, one-stop entry point for languages bindings
 173  * and protocol bindings.
 174  *
 175  * FIXME: Document this function further, in particular the possible
 176  * values for rcode in the callback.  In short, we map ACK_COMPLETE to
 177  * RCODE_COMPLETE, internal errors set errno and set rcode to
 178  * RCODE_SEND_ERROR (which is out of range for standard ieee1394
 179  * rcodes).  All other rcodes are forwarded unchanged.  For all
 180  * errors, payload is NULL, length is 0.
 181  *
 182  * Can not expect the callback to be called before the function
 183  * returns, though this does happen in some cases (ACK_COMPLETE and
 184  * errors).
 185  *
 186  * The payload is only used for write requests and must not be freed
 187  * until the callback has been called.
 188  *
 189  * @param card the card from which to send the request
 190  * @param tcode the tcode for this transaction.  Do not use
 191  *   TCODE_LOCK_REQUEST directly, insted use TCODE_LOCK_MASK_SWAP
 192  *   etc. to specify tcode and ext_tcode.
 193  * @param node_id the node_id of the destination node
 194  * @param generation the generation for which node_id is valid
 195  * @param speed the speed to use for sending the request
 196  * @param offset the 48 bit offset on the destination node
 197  * @param payload the data payload for the request subaction
 198  * @param length the length in bytes of the data to read
 199  * @param callback function to be called when the transaction is completed
 200  * @param callback_data pointer to arbitrary data, which will be
 201  *   passed to the callback
 202  */
 203 void
 204 fw_send_request(struct fw_card *card, struct fw_transaction *t,
 205                 int tcode, int node_id, int generation, int speed,
 206                 unsigned long long offset,
 207                 void *payload, size_t length,
 208                 fw_transaction_callback_t callback, void *callback_data)
 209 {
 210         unsigned long flags;
 211         int tlabel;
 212
 213         /* Bump the flush timer up 100ms first of all so we
 214          * don't race with a flush timer callback. */
 215
 216         mod_timer(&card->flush_timer, jiffies + DIV_ROUND_UP(HZ, 10));
 217
 218         /* Allocate tlabel from the bitmap and put the transaction on
 219          * the list while holding the card spinlock. */
 220
 221         spin_lock_irqsave(&card->lock, flags);
 222
 223         tlabel = card->current_tlabel;
 224         if (card->tlabel_mask & (1 << tlabel)) {
 225                 spin_unlock_irqrestore(&card->lock, flags);
 226                 callback(card, RCODE_SEND_ERROR, NULL, 0, callback_data);
 227                 return;
 228         }
 229
 230         card->current_tlabel = (card->current_tlabel + 1) & 0x1f;
 231         card->tlabel_mask |= (1 << tlabel);
 232
 233         list_add_tail(&t->link, &card->transaction_list);
 234
 235         spin_unlock_irqrestore(&card->lock, flags);
 236
 237         /* Initialize rest of transaction, fill out packet and send it. */
 238         t->node_id = node_id;
 239         t->tlabel = tlabel;
 240         t->callback = callback;
 241         t->callback_data = callback_data;
 242
 243         fw_fill_packet(&t->packet, tcode, t->tlabel,
 244                        node_id, generation, speed, offset, payload, length);
 245         t->packet.callback = transmit_complete_callback;
 246
 247         card->driver->send_request(card, &t->packet);
 248 }
 249 EXPORT_SYMBOL(fw_send_request);
 250
 251 static void
 252 transmit_phy_packet_callback(struct fw_packet *packet,
 253                              struct fw_card *card, int status)
 254 {
 255         kfree(packet);
 256 }
 257
 258 static void send_phy_packet(struct fw_card *card, u32 data, int generation)
 259 {
 260         struct fw_packet *packet;
 261
 262         packet = kzalloc(sizeof *packet, GFP_ATOMIC);
 263         if (packet == NULL)
 264                 return;
 265
 266         packet->header[0] = data;
 267         packet->header[1] = ~data;
 268         packet->header_length = 8;
 269         packet->payload_length = 0;
 270         packet->speed = SCODE_100;
 271         packet->generation = generation;
 272         packet->callback = transmit_phy_packet_callback;
 273
 274         card->driver->send_request(card, packet);
 275 }
 276
 277 void fw_send_force_root(struct fw_card *card, int node_id, int generation)
 278 {
 279         u32 q;
 280
 281         q = phy_identifier(PHY_PACKET_CONFIG) | phy_config_root_id(node_id);
 282         send_phy_packet(card, q, generation);
 283 }
 284
 285 void fw_flush_transactions(struct fw_card *card)
 286 {
 287         struct fw_transaction *t, *next;
 288         struct list_head list;
 289         unsigned long flags;
 290
 291         INIT_LIST_HEAD(&list);
 292         spin_lock_irqsave(&card->lock, flags);
 293         list_splice_init(&card->transaction_list, &list);
 294         card->tlabel_mask = 0;
 295         spin_unlock_irqrestore(&card->lock, flags);
 296
 297         list_for_each_entry_safe(t, next, &list, link)
 298                 t->callback(card, RCODE_CANCELLED, NULL, 0, t->callback_data);
 299 }
 300
 301 static struct fw_address_handler *
 302 lookup_overlapping_address_handler(struct list_head *list,
 303                                    unsigned long long offset, size_t length)
 304 {
 305         struct fw_address_handler *handler;
 306
 307         list_for_each_entry(handler, list, link) {
 308                 if (handler->offset < offset + length &&
 309                     offset < handler->offset + handler->length)
 310                         return handler;
 311         }
 312
 313         return NULL;
 314 }
 315
 316 static struct fw_address_handler *
 317 lookup_enclosing_address_handler(struct list_head *list,
 318                                  unsigned long long offset, size_t length)
 319 {
 320         struct fw_address_handler *handler;
 321
 322         list_for_each_entry(handler, list, link) {
 323                 if (handler->offset <= offset &&
 324                     offset + length <= handler->offset + handler->length)
 325                         return handler;
 326         }
 327
 328         return NULL;
 329 }
 330
 331 static DEFINE_SPINLOCK(address_handler_lock);
 332 static LIST_HEAD(address_handler_list);
 333
 334 struct fw_address_region fw_low_memory_region =
 335         { 0x000000000000ull, 0x000100000000ull };
 336 struct fw_address_region fw_high_memory_region =
 337         { 0x000100000000ull, 0xffffe0000000ull };
 338 struct fw_address_region fw_private_region =
 339         { 0xffffe0000000ull, 0xfffff0000000ull };
 340 struct fw_address_region fw_csr_region =
 341         { 0xfffff0000000ULL, 0xfffff0000800ull };
 342 struct fw_address_region fw_unit_space_region =
 343         { 0xfffff0000900ull, 0x1000000000000ull };
 344
 345 EXPORT_SYMBOL(fw_low_memory_region);
 346 EXPORT_SYMBOL(fw_high_memory_region);
 347 EXPORT_SYMBOL(fw_private_region);
 348 EXPORT_SYMBOL(fw_csr_region);
 349 EXPORT_SYMBOL(fw_unit_space_region);
 350
 351 /**
 352  * Allocate a range of addresses in the node space of the OHCI
 353  * controller.  When a request is received that falls within the
 354  * specified address range, the specified callback is invoked.  The
 355  * parameters passed to the callback give the details of the
 356  * particular request
 357  */
 358
 359 int
 360 fw_core_add_address_handler(struct fw_address_handler *handler,
 361                             struct fw_address_region *region)
 362 {
 363         struct fw_address_handler *other;
 364         unsigned long flags;
 365         int ret = -EBUSY;
 366
 367         spin_lock_irqsave(&address_handler_lock, flags);
 368
 369         handler->offset = region->start;
 370         while (handler->offset + handler->length <= region->end) {
 371                 other =
 372                     lookup_overlapping_address_handler(&address_handler_list,
 373                                                        handler->offset,
 374                                                        handler->length);
 375                 if (other != NULL) {
 376                         handler->offset += other->length;
 377                 } else {
 378                         list_add_tail(&handler->link, &address_handler_list);
 379                         ret = 0;
 380                         break;
 381                 }
 382         }
 383
 384         spin_unlock_irqrestore(&address_handler_lock, flags);
 385
 386         return ret;
 387 }
 388
 389 EXPORT_SYMBOL(fw_core_add_address_handler);
 390
 391 /**
 392  * Deallocate a range of addresses allocated with fw_allocate.  This
 393  * will call the associated callback one last time with a the special
 394  * tcode TCODE_DEALLOCATE, to let the client destroy the registered
 395  * callback data.  For convenience, the callback parameters offset and
 396  * length are set to the start and the length respectively for the
 397  * deallocated region, payload is set to NULL.
 398  */
 399
 400 void fw_core_remove_address_handler(struct fw_address_handler *handler)
 401 {
 402         unsigned long flags;
 403
 404         spin_lock_irqsave(&address_handler_lock, flags);
 405         list_del(&handler->link);
 406         spin_unlock_irqrestore(&address_handler_lock, flags);
 407 }
 408
 409 EXPORT_SYMBOL(fw_core_remove_address_handler);
 410
 411 struct fw_request {
 412         struct fw_packet response;
 413         int ack;
 414         u32 length;
 415         u32 data[0];
 416 };
 417
 418 static void
 419 free_response_callback(struct fw_packet *packet,
 420                        struct fw_card *card, int status)
 421 {
 422         struct fw_request *request;
 423
 424         request = container_of(packet, struct fw_request, response);
 425         kfree(request);
 426 }
 427
 428 static void
 429 fw_fill_response(struct fw_packet *response,
 430                  u32 *request, u32 *data, size_t length)
 431 {
 432         int tcode, tlabel, extended_tcode, source, destination;
 433
 434         tcode          = header_get_tcode(request[0]);
 435         tlabel         = header_get_tlabel(request[0]);
 436         source         = header_get_destination(request[0]);
 437         destination    = header_get_source(request[1]);
 438         extended_tcode = header_get_extended_tcode(request[3]);
 439
 440         response->header[0] =
 441                 header_retry(RETRY_1) |
 442                 header_tlabel(tlabel) |
 443                 header_destination(destination);
 444         response->header[1] = header_source(source);
 445         response->header[2] = 0;
 446
 447         switch (tcode) {
 448         case TCODE_WRITE_QUADLET_REQUEST:
 449         case TCODE_WRITE_BLOCK_REQUEST:
 450                 response->header[0] |= header_tcode(TCODE_WRITE_RESPONSE);
 451                 response->header_length = 12;
 452                 response->payload_length = 0;
 453                 break;
 454
 455         case TCODE_READ_QUADLET_REQUEST:
 456                 response->header[0] |=
 457                         header_tcode(TCODE_READ_QUADLET_RESPONSE);
 458                 response->header[3] = 0;
 459                 response->header_length = 16;
 460                 response->payload_length = 0;
 461                 break;
 462
 463         case TCODE_READ_BLOCK_REQUEST:
 464         case TCODE_LOCK_REQUEST:
 465                 response->header[0] |= header_tcode(tcode + 2);
 466                 response->header[3] =
 467                         header_data_length(length) |
 468                         header_extended_tcode(extended_tcode);
 469                 response->header_length = 16;
 470                 response->payload = data;
 471                 response->payload_length = length;
 472                 break;
 473
 474         default:
 475                 BUG();
 476                 return;
 477         }
 478 }
 479
 480 static struct fw_request *
 481 allocate_request(u32 *header, int ack,
 482                  int speed, int timestamp, int generation)
 483 {
 484         struct fw_request *request;
 485         u32 *data, length;
 486         int request_tcode;
 487
 488         request_tcode = header_get_tcode(header[0]);
 489         switch (request_tcode) {
 490         case TCODE_WRITE_QUADLET_REQUEST:
 491                 data = &header[3];
 492                 length = 4;
 493                 break;
 494
 495         case TCODE_WRITE_BLOCK_REQUEST:
 496         case TCODE_LOCK_REQUEST:
 497                 data = &header[4];
 498                 length = header_get_data_length(header[3]);
 499                 break;
 500
 501         case TCODE_READ_QUADLET_REQUEST:
 502                 data = NULL;
 503                 length = 4;
 504                 break;
 505
 506         case TCODE_READ_BLOCK_REQUEST:
 507                 data = NULL;
 508                 length = header_get_data_length(header[3]);
 509                 break;
 510
 511         default:
 512                 BUG();
 513                 return NULL;
 514         }
 515
 516         request = kmalloc(sizeof *request + length, GFP_ATOMIC);
 517         if (request == NULL)
 518                 return NULL;
 519
 520         request->response.speed = speed;
 521         request->response.timestamp = timestamp;
 522         request->response.generation = generation;
 523         request->response.callback = free_response_callback;
 524         request->ack = ack;
 525         request->length = length;
 526         if (data)
 527                 memcpy(request->data, data, length);
 528
 529         fw_fill_response(&request->response, header, request->data, length);
 530
 531         return request;
 532 }
 533
 534 void
 535 fw_send_response(struct fw_card *card, struct fw_request *request, int rcode)
 536 {
 537         int response_tcode;
 538
 539         /* Broadcast packets are reported as ACK_COMPLETE, so this
 540          * check is sufficient to ensure we don't send response to
 541          * broadcast packets or posted writes. */
 542         if (request->ack != ACK_PENDING)
 543                 return;
 544
 545         request->response.header[1] |= header_rcode(rcode);
 546         response_tcode = header_get_tcode(request->response.header[0]);
 547         if (rcode != RCODE_COMPLETE)
 548                 /* Clear the data_length field. */
 549                 request->response.header[3] &= 0xffff;
 550         else if (response_tcode == TCODE_READ_QUADLET_RESPONSE)
 551                 request->response.header[3] = request->data[0];
 552
 553         card->driver->send_response(card, &request->response);
 554 }
 555
 556 EXPORT_SYMBOL(fw_send_response);
 557
 558 void
 559 fw_core_handle_request(struct fw_card *card,
 560                        int speed, int ack, int timestamp,
 561                        int generation, u32 length, u32 *header)
 562 {
 563         struct fw_address_handler *handler;
 564         struct fw_request *request;
 565         unsigned long long offset;
 566         unsigned long flags;
 567         int tcode, destination, source, t;
 568
 569         if (length > 2048) {
 570                 /* FIXME: send error response. */
 571                 return;
 572         }
 573
 574         if (ack != ACK_PENDING && ack != ACK_COMPLETE)
 575                 return;
 576
 577         t = (timestamp & 0x1fff) + 4000;
 578         if (t >= 8000)
 579                 t = (timestamp & ~0x1fff) + 0x2000 + t - 8000;
 580         else
 581                 t = (timestamp & ~0x1fff) + t;
 582
 583         request = allocate_request(header, ack, speed, t, generation);
 584         if (request == NULL) {
 585                 /* FIXME: send statically allocated busy packet. */
 586                 return;
 587         }
 588
 589         offset      =
 590                 ((unsigned long long)
 591                  header_get_offset_high(header[1]) << 32) | header[2];
 592         tcode       = header_get_tcode(header[0]);
 593         destination = header_get_destination(header[0]);
 594         source      = header_get_source(header[0]);
 595
 596         spin_lock_irqsave(&address_handler_lock, flags);
 597         handler = lookup_enclosing_address_handler(&address_handler_list,
 598                                                    offset, request->length);
 599         spin_unlock_irqrestore(&address_handler_lock, flags);
 600
 601         /* FIXME: lookup the fw_node corresponding to the sender of
 602          * this request and pass that to the address handler instead
 603          * of the node ID.  We may also want to move the address
 604          * allocations to fw_node so we only do this callback if the
 605          * upper layers registered it for this node. */
 606
 607         if (handler == NULL)
 608                 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
 609         else
 610                 handler->address_callback(card, request,
 611                                           tcode, destination, source,
 612                                           generation, speed, offset,
 613                                           request->data, request->length,
 614                                           handler->callback_data);
 615 }
 616
 617 EXPORT_SYMBOL(fw_core_handle_request);
 618
 619 void
 620 fw_core_handle_response(struct fw_card *card,
 621                         int speed, int ack, int timestamp,
 622                         u32 length, u32 *header)
 623 {
 624         struct fw_transaction *t;
 625         unsigned long flags;
 626         u32 *data;
 627         size_t data_length;
 628         int tcode, tlabel, destination, source, rcode;
 629
 630         tcode       = header_get_tcode(header[0]);
 631         tlabel      = header_get_tlabel(header[0]);
 632         destination = header_get_destination(header[0]);
 633         source      = header_get_source(header[1]);
 634         rcode       = header_get_rcode(header[1]);
 635
 636         spin_lock_irqsave(&card->lock, flags);
 637         list_for_each_entry(t, &card->transaction_list, link) {
 638                 if (t->node_id == source && t->tlabel == tlabel) {
 639                         list_del(&t->link);
 640                         card->tlabel_mask &= ~(1 << t->tlabel);
 641                         break;
 642                 }
 643         }
 644         spin_unlock_irqrestore(&card->lock, flags);
 645
 646         if (&t->link == &card->transaction_list) {
 647                 fw_notify("Unsolicited response\n");
 648                 return;
 649         }
 650
 651         /* FIXME: sanity check packet, is length correct, does tcodes
 652          * and addresses match. */
 653
 654         switch (tcode) {
 655         case TCODE_READ_QUADLET_RESPONSE:
 656                 data = (u32 *) &header[3];
 657                 data_length = 4;
 658                 break;
 659
 660         case TCODE_WRITE_RESPONSE:
 661                 data = NULL;
 662                 data_length = 0;
 663                 break;
 664
 665         case TCODE_READ_BLOCK_RESPONSE:
 666         case TCODE_LOCK_RESPONSE:
 667                 data = &header[4];
 668                 data_length = header_get_data_length(header[3]);
 669                 break;
 670
 671         default:
 672                 /* Should never happen, this is just to shut up gcc. */
 673                 data = NULL;
 674                 data_length = 0;
 675                 break;
 676         }
 677
 678         t->callback(card, rcode, data, data_length, t->callback_data);
 679 }
 680
 681 EXPORT_SYMBOL(fw_core_handle_response);
 682
 683 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
 684 MODULE_DESCRIPTION("Core IEEE1394 transaction logic");
 685 MODULE_LICENSE("GPL");
 686
 687 static u32 vendor_textual_descriptor_data[] = {
 688         /* textual descriptor leaf () */
 689         0x00080000,
 690         0x00000000,
 691         0x00000000,
 692         0x4c696e75,             /* L i n u */
 693         0x78204669,             /* x   F i */
 694         0x72657769,             /* r e w i */
 695         0x72652028,             /* r e   ( */
 696         0x4a554a55,             /* J U J U */
 697         0x29000000,             /* )       */
 698 };
 699
 700 static struct fw_descriptor vendor_textual_descriptor = {
 701         .length = ARRAY_SIZE(vendor_textual_descriptor_data),
 702         .key = 0x81000000,
 703         .data = vendor_textual_descriptor_data
 704 };
 705
 706 static int __init fw_core_init(void)
 707 {
 708         int retval;
 709
 710         retval = bus_register(&fw_bus_type);
 711         if (retval < 0)
 712                 return retval;
 713
 714         /* Add the vendor textual descriptor. */
 715         retval = fw_core_add_descriptor(&vendor_textual_descriptor);
 716         BUG_ON(retval < 0);
 717
 718         return 0;
 719 }
 720
 721 static void __exit fw_core_cleanup(void)
 722 {
 723         bus_unregister(&fw_bus_type);
 724 }
 725
 726 module_init(fw_core_init);
 727 module_exit(fw_core_cleanup);