release/src-rt-6.x.4708/linux/linux-2.6.36/drivers/pci/hotplug/cpci_hotplug_core.c

   1 /*
   2  * CompactPCI Hot Plug Driver
   3  *
   4  * Copyright (C) 2002,2005 SOMA Networks, Inc.
   5  * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
   6  * Copyright (C) 2001 IBM Corp.
   7  *
   8  * All rights reserved.
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or (at
  13  * your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful, but
  16  * WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  18  * NON INFRINGEMENT.  See the GNU General Public License for more
  19  * details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  24  *
  25  * Send feedback to <scottm@somanetworks.com>
  26  */
  27
  28 #include <linux/module.h>
  29 #include <linux/kernel.h>
  30 #include <linux/slab.h>
  31 #include <linux/pci.h>
  32 #include <linux/pci_hotplug.h>
  33 #include <linux/init.h>
  34 #include <linux/interrupt.h>
  35 #include <asm/atomic.h>
  36 #include <linux/delay.h>
  37 #include <linux/kthread.h>
  38 #include "cpci_hotplug.h"
  39
  40 #define DRIVER_AUTHOR   "Scott Murray <scottm@somanetworks.com>"
  41 #define DRIVER_DESC     "CompactPCI Hot Plug Core"
  42
  43 #define MY_NAME "cpci_hotplug"
  44
  45 #define dbg(format, arg...)                                     \
  46         do {                                                    \
  47                 if (cpci_debug)                                 \
  48                         printk (KERN_DEBUG "%s: " format "\n",  \
  49                                 MY_NAME , ## arg);              \
  50         } while (0)
  51 #define err(format, arg...) printk(KERN_ERR "%s: " format "\n", MY_NAME , ## arg)
  52 #define info(format, arg...) printk(KERN_INFO "%s: " format "\n", MY_NAME , ## arg)
  53 #define warn(format, arg...) printk(KERN_WARNING "%s: " format "\n", MY_NAME , ## arg)
  54
  55 /* local variables */
  56 static DECLARE_RWSEM(list_rwsem);
  57 static LIST_HEAD(slot_list);
  58 static int slots;
  59 static atomic_t extracting;
  60 int cpci_debug;
  61 static struct cpci_hp_controller *controller;
  62 static struct task_struct *cpci_thread;
  63 static int thread_finished;
  64
  65 static int enable_slot(struct hotplug_slot *slot);
  66 static int disable_slot(struct hotplug_slot *slot);
  67 static int set_attention_status(struct hotplug_slot *slot, u8 value);
  68 static int get_power_status(struct hotplug_slot *slot, u8 * value);
  69 static int get_attention_status(struct hotplug_slot *slot, u8 * value);
  70 static int get_adapter_status(struct hotplug_slot *slot, u8 * value);
  71 static int get_latch_status(struct hotplug_slot *slot, u8 * value);
  72
  73 static struct hotplug_slot_ops cpci_hotplug_slot_ops = {
  74         .enable_slot = enable_slot,
  75         .disable_slot = disable_slot,
  76         .set_attention_status = set_attention_status,
  77         .get_power_status = get_power_status,
  78         .get_attention_status = get_attention_status,
  79         .get_adapter_status = get_adapter_status,
  80         .get_latch_status = get_latch_status,
  81 };
  82
  83 static int
  84 update_latch_status(struct hotplug_slot *hotplug_slot, u8 value)
  85 {
  86         struct hotplug_slot_info info;
  87
  88         memcpy(&info, hotplug_slot->info, sizeof(struct hotplug_slot_info));
  89         info.latch_status = value;
  90         return pci_hp_change_slot_info(hotplug_slot, &info);
  91 }
  92
  93 static int
  94 update_adapter_status(struct hotplug_slot *hotplug_slot, u8 value)
  95 {
  96         struct hotplug_slot_info info;
  97
  98         memcpy(&info, hotplug_slot->info, sizeof(struct hotplug_slot_info));
  99         info.adapter_status = value;
 100         return pci_hp_change_slot_info(hotplug_slot, &info);
 101 }
 102
 103 static int
 104 enable_slot(struct hotplug_slot *hotplug_slot)
 105 {
 106         struct slot *slot = hotplug_slot->private;
 107         int retval = 0;
 108
 109         dbg("%s - physical_slot = %s", __func__, slot_name(slot));
 110
 111         if (controller->ops->set_power)
 112                 retval = controller->ops->set_power(slot, 1);
 113         return retval;
 114 }
 115
 116 static int
 117 disable_slot(struct hotplug_slot *hotplug_slot)
 118 {
 119         struct slot *slot = hotplug_slot->private;
 120         int retval = 0;
 121
 122         dbg("%s - physical_slot = %s", __func__, slot_name(slot));
 123
 124         down_write(&list_rwsem);
 125
 126         /* Unconfigure device */
 127         dbg("%s - unconfiguring slot %s", __func__, slot_name(slot));
 128         if ((retval = cpci_unconfigure_slot(slot))) {
 129                 err("%s - could not unconfigure slot %s",
 130                     __func__, slot_name(slot));
 131                 goto disable_error;
 132         }
 133         dbg("%s - finished unconfiguring slot %s", __func__, slot_name(slot));
 134
 135         /* Clear EXT (by setting it) */
 136         if (cpci_clear_ext(slot)) {
 137                 err("%s - could not clear EXT for slot %s",
 138                     __func__, slot_name(slot));
 139                 retval = -ENODEV;
 140                 goto disable_error;
 141         }
 142         cpci_led_on(slot);
 143
 144         if (controller->ops->set_power)
 145                 if ((retval = controller->ops->set_power(slot, 0)))
 146                         goto disable_error;
 147
 148         if (update_adapter_status(slot->hotplug_slot, 0))
 149                 warn("failure to update adapter file");
 150
 151         if (slot->extracting) {
 152                 slot->extracting = 0;
 153                 atomic_dec(&extracting);
 154         }
 155 disable_error:
 156         up_write(&list_rwsem);
 157         return retval;
 158 }
 159
 160 static u8
 161 cpci_get_power_status(struct slot *slot)
 162 {
 163         u8 power = 1;
 164
 165         if (controller->ops->get_power)
 166                 power = controller->ops->get_power(slot);
 167         return power;
 168 }
 169
 170 static int
 171 get_power_status(struct hotplug_slot *hotplug_slot, u8 * value)
 172 {
 173         struct slot *slot = hotplug_slot->private;
 174
 175         *value = cpci_get_power_status(slot);
 176         return 0;
 177 }
 178
 179 static int
 180 get_attention_status(struct hotplug_slot *hotplug_slot, u8 * value)
 181 {
 182         struct slot *slot = hotplug_slot->private;
 183
 184         *value = cpci_get_attention_status(slot);
 185         return 0;
 186 }
 187
 188 static int
 189 set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
 190 {
 191         return cpci_set_attention_status(hotplug_slot->private, status);
 192 }
 193
 194 static int
 195 get_adapter_status(struct hotplug_slot *hotplug_slot, u8 * value)
 196 {
 197         *value = hotplug_slot->info->adapter_status;
 198         return 0;
 199 }
 200
 201 static int
 202 get_latch_status(struct hotplug_slot *hotplug_slot, u8 * value)
 203 {
 204         *value = hotplug_slot->info->latch_status;
 205         return 0;
 206 }
 207
 208 static void release_slot(struct hotplug_slot *hotplug_slot)
 209 {
 210         struct slot *slot = hotplug_slot->private;
 211
 212         kfree(slot->hotplug_slot->info);
 213         kfree(slot->hotplug_slot);
 214         if (slot->dev)
 215                 pci_dev_put(slot->dev);
 216         kfree(slot);
 217 }
 218
 219 #define SLOT_NAME_SIZE  6
 220
 221 int
 222 cpci_hp_register_bus(struct pci_bus *bus, u8 first, u8 last)
 223 {
 224         struct slot *slot;
 225         struct hotplug_slot *hotplug_slot;
 226         struct hotplug_slot_info *info;
 227         char name[SLOT_NAME_SIZE];
 228         int status = -ENOMEM;
 229         int i;
 230
 231         if (!(controller && bus))
 232                 return -ENODEV;
 233
 234         /*
 235          * Create a structure for each slot, and register that slot
 236          * with the pci_hotplug subsystem.
 237          */
 238         for (i = first; i <= last; ++i) {
 239                 slot = kzalloc(sizeof (struct slot), GFP_KERNEL);
 240                 if (!slot)
 241                         goto error;
 242
 243                 hotplug_slot =
 244                         kzalloc(sizeof (struct hotplug_slot), GFP_KERNEL);
 245                 if (!hotplug_slot)
 246                         goto error_slot;
 247                 slot->hotplug_slot = hotplug_slot;
 248
 249                 info = kzalloc(sizeof (struct hotplug_slot_info), GFP_KERNEL);
 250                 if (!info)
 251                         goto error_hpslot;
 252                 hotplug_slot->info = info;
 253
 254                 slot->bus = bus;
 255                 slot->number = i;
 256                 slot->devfn = PCI_DEVFN(i, 0);
 257
 258                 snprintf(name, SLOT_NAME_SIZE, "%02x:%02x", bus->number, i);
 259
 260                 hotplug_slot->private = slot;
 261                 hotplug_slot->release = &release_slot;
 262                 hotplug_slot->ops = &cpci_hotplug_slot_ops;
 263
 264                 /*
 265                  * Initialize the slot info structure with some known
 266                  * good values.
 267                  */
 268                 dbg("initializing slot %s", name);
 269                 info->power_status = cpci_get_power_status(slot);
 270                 info->attention_status = cpci_get_attention_status(slot);
 271
 272                 dbg("registering slot %s", name);
 273                 status = pci_hp_register(slot->hotplug_slot, bus, i, name);
 274                 if (status) {
 275                         err("pci_hp_register failed with error %d", status);
 276                         goto error_info;
 277                 }
 278                 dbg("slot registered with name: %s", slot_name(slot));
 279
 280                 /* Add slot to our internal list */
 281                 down_write(&list_rwsem);
 282                 list_add(&slot->slot_list, &slot_list);
 283                 slots++;
 284                 up_write(&list_rwsem);
 285         }
 286         return 0;
 287 error_info:
 288         kfree(info);
 289 error_hpslot:
 290         kfree(hotplug_slot);
 291 error_slot:
 292         kfree(slot);
 293 error:
 294         return status;
 295 }
 296
 297 int
 298 cpci_hp_unregister_bus(struct pci_bus *bus)
 299 {
 300         struct slot *slot;
 301         struct slot *tmp;
 302         int status = 0;
 303
 304         down_write(&list_rwsem);
 305         if (!slots) {
 306                 up_write(&list_rwsem);
 307                 return -1;
 308         }
 309         list_for_each_entry_safe(slot, tmp, &slot_list, slot_list) {
 310                 if (slot->bus == bus) {
 311                         list_del(&slot->slot_list);
 312                         slots--;
 313
 314                         dbg("deregistering slot %s", slot_name(slot));
 315                         status = pci_hp_deregister(slot->hotplug_slot);
 316                         if (status) {
 317                                 err("pci_hp_deregister failed with error %d",
 318                                     status);
 319                                 break;
 320                         }
 321                 }
 322         }
 323         up_write(&list_rwsem);
 324         return status;
 325 }
 326
 327 /* This is the interrupt mode interrupt handler */
 328 static irqreturn_t
 329 cpci_hp_intr(int irq, void *data)
 330 {
 331         dbg("entered cpci_hp_intr");
 332
 333         /* Check to see if it was our interrupt */
 334         if ((controller->irq_flags & IRQF_SHARED) &&
 335             !controller->ops->check_irq(controller->dev_id)) {
 336                 dbg("exited cpci_hp_intr, not our interrupt");
 337                 return IRQ_NONE;
 338         }
 339
 340         /* Disable ENUM interrupt */
 341         controller->ops->disable_irq();
 342
 343         /* Trigger processing by the event thread */
 344         wake_up_process(cpci_thread);
 345         return IRQ_HANDLED;
 346 }
 347
 348 /*
 349  * According to PICMG 2.1 R2.0, section 6.3.2, upon
 350  * initialization, the system driver shall clear the
 351  * INS bits of the cold-inserted devices.
 352  */
 353 static int
 354 init_slots(int clear_ins)
 355 {
 356         struct slot *slot;
 357         struct pci_dev* dev;
 358
 359         dbg("%s - enter", __func__);
 360         down_read(&list_rwsem);
 361         if (!slots) {
 362                 up_read(&list_rwsem);
 363                 return -1;
 364         }
 365         list_for_each_entry(slot, &slot_list, slot_list) {
 366                 dbg("%s - looking at slot %s", __func__, slot_name(slot));
 367                 if (clear_ins && cpci_check_and_clear_ins(slot))
 368                         dbg("%s - cleared INS for slot %s",
 369                             __func__, slot_name(slot));
 370                 dev = pci_get_slot(slot->bus, PCI_DEVFN(slot->number, 0));
 371                 if (dev) {
 372                         if (update_adapter_status(slot->hotplug_slot, 1))
 373                                 warn("failure to update adapter file");
 374                         if (update_latch_status(slot->hotplug_slot, 1))
 375                                 warn("failure to update latch file");
 376                         slot->dev = dev;
 377                 }
 378         }
 379         up_read(&list_rwsem);
 380         dbg("%s - exit", __func__);
 381         return 0;
 382 }
 383
 384 static int
 385 check_slots(void)
 386 {
 387         struct slot *slot;
 388         int extracted;
 389         int inserted;
 390         u16 hs_csr;
 391
 392         down_read(&list_rwsem);
 393         if (!slots) {
 394                 up_read(&list_rwsem);
 395                 err("no slots registered, shutting down");
 396                 return -1;
 397         }
 398         extracted = inserted = 0;
 399         list_for_each_entry(slot, &slot_list, slot_list) {
 400                 dbg("%s - looking at slot %s", __func__, slot_name(slot));
 401                 if (cpci_check_and_clear_ins(slot)) {
 402                         /*
 403                          * Some broken hardware (e.g. PLX 9054AB) asserts
 404                          * ENUM# twice...
 405                          */
 406                         if (slot->dev) {
 407                                 warn("slot %s already inserted",
 408                                      slot_name(slot));
 409                                 inserted++;
 410                                 continue;
 411                         }
 412
 413                         /* Process insertion */
 414                         dbg("%s - slot %s inserted", __func__, slot_name(slot));
 415
 416                         /* GSM, debug */
 417                         hs_csr = cpci_get_hs_csr(slot);
 418                         dbg("%s - slot %s HS_CSR (1) = %04x",
 419                             __func__, slot_name(slot), hs_csr);
 420
 421                         /* Configure device */
 422                         dbg("%s - configuring slot %s",
 423                             __func__, slot_name(slot));
 424                         if (cpci_configure_slot(slot)) {
 425                                 err("%s - could not configure slot %s",
 426                                     __func__, slot_name(slot));
 427                                 continue;
 428                         }
 429                         dbg("%s - finished configuring slot %s",
 430                             __func__, slot_name(slot));
 431
 432                         /* GSM, debug */
 433                         hs_csr = cpci_get_hs_csr(slot);
 434                         dbg("%s - slot %s HS_CSR (2) = %04x",
 435                             __func__, slot_name(slot), hs_csr);
 436
 437                         if (update_latch_status(slot->hotplug_slot, 1))
 438                                 warn("failure to update latch file");
 439
 440                         if (update_adapter_status(slot->hotplug_slot, 1))
 441                                 warn("failure to update adapter file");
 442
 443                         cpci_led_off(slot);
 444
 445                         /* GSM, debug */
 446                         hs_csr = cpci_get_hs_csr(slot);
 447                         dbg("%s - slot %s HS_CSR (3) = %04x",
 448                             __func__, slot_name(slot), hs_csr);
 449
 450                         inserted++;
 451                 } else if (cpci_check_ext(slot)) {
 452                         /* Process extraction request */
 453                         dbg("%s - slot %s extracted",
 454                             __func__, slot_name(slot));
 455
 456                         /* GSM, debug */
 457                         hs_csr = cpci_get_hs_csr(slot);
 458                         dbg("%s - slot %s HS_CSR = %04x",
 459                             __func__, slot_name(slot), hs_csr);
 460
 461                         if (!slot->extracting) {
 462                                 if (update_latch_status(slot->hotplug_slot, 0)) {
 463                                         warn("failure to update latch file");
 464                                 }
 465                                 slot->extracting = 1;
 466                                 atomic_inc(&extracting);
 467                         }
 468                         extracted++;
 469                 } else if (slot->extracting) {
 470                         hs_csr = cpci_get_hs_csr(slot);
 471                         if (hs_csr == 0xffff) {
 472                                 /*
 473                                  * Hmmm, we're likely hosed at this point, should we
 474                                  * bother trying to tell the driver or not?
 475                                  */
 476                                 err("card in slot %s was improperly removed",
 477                                     slot_name(slot));
 478                                 if (update_adapter_status(slot->hotplug_slot, 0))
 479                                         warn("failure to update adapter file");
 480                                 slot->extracting = 0;
 481                                 atomic_dec(&extracting);
 482                         }
 483                 }
 484         }
 485         up_read(&list_rwsem);
 486         dbg("inserted=%d, extracted=%d, extracting=%d",
 487             inserted, extracted, atomic_read(&extracting));
 488         if (inserted || extracted)
 489                 return extracted;
 490         else if (!atomic_read(&extracting)) {
 491                 err("cannot find ENUM# source, shutting down");
 492                 return -1;
 493         }
 494         return 0;
 495 }
 496
 497 /* This is the interrupt mode worker thread body */
 498 static int
 499 event_thread(void *data)
 500 {
 501         int rc;
 502
 503         dbg("%s - event thread started", __func__);
 504         while (1) {
 505                 dbg("event thread sleeping");
 506                 set_current_state(TASK_INTERRUPTIBLE);
 507                 schedule();
 508                 if (kthread_should_stop())
 509                         break;
 510                 do {
 511                         rc = check_slots();
 512                         if (rc > 0) {
 513                                 /* Give userspace a chance to handle extraction */
 514                                 msleep(500);
 515                         } else if (rc < 0) {
 516                                 dbg("%s - error checking slots", __func__);
 517                                 thread_finished = 1;
 518                                 goto out;
 519                         }
 520                 } while (atomic_read(&extracting) && !kthread_should_stop());
 521                 if (kthread_should_stop())
 522                         break;
 523
 524                 /* Re-enable ENUM# interrupt */
 525                 dbg("%s - re-enabling irq", __func__);
 526                 controller->ops->enable_irq();
 527         }
 528  out:
 529         return 0;
 530 }
 531
 532 /* This is the polling mode worker thread body */
 533 static int
 534 poll_thread(void *data)
 535 {
 536         int rc;
 537
 538         while (1) {
 539                 if (kthread_should_stop() || signal_pending(current))
 540                         break;
 541                 if (controller->ops->query_enum()) {
 542                         do {
 543                                 rc = check_slots();
 544                                 if (rc > 0) {
 545                                         /* Give userspace a chance to handle extraction */
 546                                         msleep(500);
 547                                 } else if (rc < 0) {
 548                                         dbg("%s - error checking slots", __func__);
 549                                         thread_finished = 1;
 550                                         goto out;
 551                                 }
 552                         } while (atomic_read(&extracting) && !kthread_should_stop());
 553                 }
 554                 msleep(100);
 555         }
 556  out:
 557         return 0;
 558 }
 559
 560 static int
 561 cpci_start_thread(void)
 562 {
 563         if (controller->irq)
 564                 cpci_thread = kthread_run(event_thread, NULL, "cpci_hp_eventd");
 565         else
 566                 cpci_thread = kthread_run(poll_thread, NULL, "cpci_hp_polld");
 567         if (IS_ERR(cpci_thread)) {
 568                 err("Can't start up our thread");
 569                 return PTR_ERR(cpci_thread);
 570         }
 571         thread_finished = 0;
 572         return 0;
 573 }
 574
 575 static void
 576 cpci_stop_thread(void)
 577 {
 578         kthread_stop(cpci_thread);
 579         thread_finished = 1;
 580 }
 581
 582 int
 583 cpci_hp_register_controller(struct cpci_hp_controller *new_controller)
 584 {
 585         int status = 0;
 586
 587         if (controller)
 588                 return -1;
 589         if (!(new_controller && new_controller->ops))
 590                 return -EINVAL;
 591         if (new_controller->irq) {
 592                 if (!(new_controller->ops->enable_irq &&
 593                      new_controller->ops->disable_irq))
 594                         status = -EINVAL;
 595                 if (request_irq(new_controller->irq,
 596                                cpci_hp_intr,
 597                                new_controller->irq_flags,
 598                                MY_NAME,
 599                                new_controller->dev_id)) {
 600                         err("Can't get irq %d for the hotplug cPCI controller",
 601                             new_controller->irq);
 602                         status = -ENODEV;
 603                 }
 604                 dbg("%s - acquired controller irq %d",
 605                     __func__, new_controller->irq);
 606         }
 607         if (!status)
 608                 controller = new_controller;
 609         return status;
 610 }
 611
 612 static void
 613 cleanup_slots(void)
 614 {
 615         struct slot *slot;
 616         struct slot *tmp;
 617
 618         /*
 619          * Unregister all of our slots with the pci_hotplug subsystem,
 620          * and free up all memory that we had allocated.
 621          */
 622         down_write(&list_rwsem);
 623         if (!slots)
 624                 goto cleanup_null;
 625         list_for_each_entry_safe(slot, tmp, &slot_list, slot_list) {
 626                 list_del(&slot->slot_list);
 627                 pci_hp_deregister(slot->hotplug_slot);
 628         }
 629 cleanup_null:
 630         up_write(&list_rwsem);
 631         return;
 632 }
 633
 634 int
 635 cpci_hp_unregister_controller(struct cpci_hp_controller *old_controller)
 636 {
 637         int status = 0;
 638
 639         if (controller) {
 640                 if (!thread_finished)
 641                         cpci_stop_thread();
 642                 if (controller->irq)
 643                         free_irq(controller->irq, controller->dev_id);
 644                 controller = NULL;
 645                 cleanup_slots();
 646         } else
 647                 status = -ENODEV;
 648         return status;
 649 }
 650
 651 int
 652 cpci_hp_start(void)
 653 {
 654         static int first = 1;
 655         int status;
 656
 657         dbg("%s - enter", __func__);
 658         if (!controller)
 659                 return -ENODEV;
 660
 661         down_read(&list_rwsem);
 662         if (list_empty(&slot_list)) {
 663                 up_read(&list_rwsem);
 664                 return -ENODEV;
 665         }
 666         up_read(&list_rwsem);
 667
 668         status = init_slots(first);
 669         if (first)
 670                 first = 0;
 671         if (status)
 672                 return status;
 673
 674         status = cpci_start_thread();
 675         if (status)
 676                 return status;
 677         dbg("%s - thread started", __func__);
 678
 679         if (controller->irq) {
 680                 /* Start enum interrupt processing */
 681                 dbg("%s - enabling irq", __func__);
 682                 controller->ops->enable_irq();
 683         }
 684         dbg("%s - exit", __func__);
 685         return 0;
 686 }
 687
 688 int
 689 cpci_hp_stop(void)
 690 {
 691         if (!controller)
 692                 return -ENODEV;
 693         if (controller->irq) {
 694                 /* Stop enum interrupt processing */
 695                 dbg("%s - disabling irq", __func__);
 696                 controller->ops->disable_irq();
 697         }
 698         cpci_stop_thread();
 699         return 0;
 700 }
 701
 702 int __init
 703 cpci_hotplug_init(int debug)
 704 {
 705         cpci_debug = debug;
 706         return 0;
 707 }
 708
 709 void __exit
 710 cpci_hotplug_exit(void)
 711 {
 712         /*
 713          * Clean everything up.
 714          */
 715         cpci_hp_stop();
 716         cpci_hp_unregister_controller(controller);
 717 }
 718
 719 EXPORT_SYMBOL_GPL(cpci_hp_register_controller);
 720 EXPORT_SYMBOL_GPL(cpci_hp_unregister_controller);
 721 EXPORT_SYMBOL_GPL(cpci_hp_register_bus);
 722 EXPORT_SYMBOL_GPL(cpci_hp_unregister_bus);
 723 EXPORT_SYMBOL_GPL(cpci_hp_start);
 724 EXPORT_SYMBOL_GPL(cpci_hp_stop);