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/config.h>
  29 #include <linux/module.h>
  30 #include <linux/kernel.h>
  31 #include <linux/slab.h>
  32 #include <linux/pci.h>
  33 #include <linux/init.h>
  34 #include <linux/interrupt.h>
  35 #include <linux/smp_lock.h>
  36 #include <asm/atomic.h>
  37 #include <linux/delay.h>
  38 #include "pci_hotplug.h"
  39 #include "cpci_hotplug.h"
  40
  41 #define DRIVER_AUTHOR   "Scott Murray <scottm@somanetworks.com>"
  42 #define DRIVER_DESC     "CompactPCI Hot Plug Core"
  43
  44 #define MY_NAME "cpci_hotplug"
  45
  46 #define dbg(format, arg...)                                     \
  47         do {                                                    \
  48                 if (cpci_debug)                                 \
  49                         printk (KERN_DEBUG "%s: " format "\n",  \
  50                                 MY_NAME , ## arg);              \
  51         } while (0)
  52 #define err(format, arg...) printk(KERN_ERR "%s: " format "\n", MY_NAME , ## arg)
  53 #define info(format, arg...) printk(KERN_INFO "%s: " format "\n", MY_NAME , ## arg)
  54 #define warn(format, arg...) printk(KERN_WARNING "%s: " format "\n", MY_NAME , ## arg)
  55
  56 /* local variables */
  57 static DECLARE_RWSEM(list_rwsem);
  58 static LIST_HEAD(slot_list);
  59 static int slots;
  60 static atomic_t extracting;
  61 int cpci_debug;
  62 static struct cpci_hp_controller *controller;
  63 static struct semaphore event_semaphore;        /* mutex for process loop (up if something to process) */
  64 static struct semaphore thread_exit;            /* guard ensure thread has exited before calling it quits */
  65 static int thread_finished = 1;
  66
  67 static int enable_slot(struct hotplug_slot *slot);
  68 static int disable_slot(struct hotplug_slot *slot);
  69 static int set_attention_status(struct hotplug_slot *slot, u8 value);
  70 static int get_power_status(struct hotplug_slot *slot, u8 * value);
  71 static int get_attention_status(struct hotplug_slot *slot, u8 * value);
  72 static int get_adapter_status(struct hotplug_slot *slot, u8 * value);
  73 static int get_latch_status(struct hotplug_slot *slot, u8 * value);
  74
  75 static struct hotplug_slot_ops cpci_hotplug_slot_ops = {
  76         .owner = THIS_MODULE,
  77         .enable_slot = enable_slot,
  78         .disable_slot = disable_slot,
  79         .set_attention_status = set_attention_status,
  80         .get_power_status = get_power_status,
  81         .get_attention_status = get_attention_status,
  82         .get_adapter_status = get_adapter_status,
  83         .get_latch_status = get_latch_status,
  84 };
  85
  86 static int
  87 update_latch_status(struct hotplug_slot *hotplug_slot, u8 value)
  88 {
  89         struct hotplug_slot_info info;
  90
  91         memcpy(&info, hotplug_slot->info, sizeof(struct hotplug_slot_info));
  92         info.latch_status = value;
  93         return pci_hp_change_slot_info(hotplug_slot, &info);
  94 }
  95
  96 static int
  97 update_adapter_status(struct hotplug_slot *hotplug_slot, u8 value)
  98 {
  99         struct hotplug_slot_info info;
 100
 101         memcpy(&info, hotplug_slot->info, sizeof(struct hotplug_slot_info));
 102         info.adapter_status = value;
 103         return pci_hp_change_slot_info(hotplug_slot, &info);
 104 }
 105
 106 static int
 107 enable_slot(struct hotplug_slot *hotplug_slot)
 108 {
 109         struct slot *slot = hotplug_slot->private;
 110         int retval = 0;
 111
 112         dbg("%s - physical_slot = %s", __FUNCTION__, hotplug_slot->name);
 113
 114         if (controller->ops->set_power)
 115                 retval = controller->ops->set_power(slot, 1);
 116         return retval;
 117 }
 118
 119 static int
 120 disable_slot(struct hotplug_slot *hotplug_slot)
 121 {
 122         struct slot *slot = hotplug_slot->private;
 123         int retval = 0;
 124
 125         dbg("%s - physical_slot = %s", __FUNCTION__, hotplug_slot->name);
 126
 127         down_write(&list_rwsem);
 128
 129         /* Unconfigure device */
 130         dbg("%s - unconfiguring slot %s",
 131             __FUNCTION__, slot->hotplug_slot->name);
 132         if ((retval = cpci_unconfigure_slot(slot))) {
 133                 err("%s - could not unconfigure slot %s",
 134                     __FUNCTION__, slot->hotplug_slot->name);
 135                 goto disable_error;
 136         }
 137         dbg("%s - finished unconfiguring slot %s",
 138             __FUNCTION__, slot->hotplug_slot->name);
 139
 140         /* Clear EXT (by setting it) */
 141         if (cpci_clear_ext(slot)) {
 142                 err("%s - could not clear EXT for slot %s",
 143                     __FUNCTION__, slot->hotplug_slot->name);
 144                 retval = -ENODEV;
 145                 goto disable_error;
 146         }
 147         cpci_led_on(slot);
 148
 149         if (controller->ops->set_power)
 150                 if ((retval = controller->ops->set_power(slot, 0)))
 151                         goto disable_error;
 152
 153         if (update_adapter_status(slot->hotplug_slot, 0))
 154                 warn("failure to update adapter file");
 155
 156         if (slot->extracting) {
 157                 slot->extracting = 0;
 158                 atomic_dec(&extracting);
 159         }
 160 disable_error:
 161         up_write(&list_rwsem);
 162         return retval;
 163 }
 164
 165 static u8
 166 cpci_get_power_status(struct slot *slot)
 167 {
 168         u8 power = 1;
 169
 170         if (controller->ops->get_power)
 171                 power = controller->ops->get_power(slot);
 172         return power;
 173 }
 174
 175 static int
 176 get_power_status(struct hotplug_slot *hotplug_slot, u8 * value)
 177 {
 178         struct slot *slot = hotplug_slot->private;
 179
 180         *value = cpci_get_power_status(slot);
 181         return 0;
 182 }
 183
 184 static int
 185 get_attention_status(struct hotplug_slot *hotplug_slot, u8 * value)
 186 {
 187         struct slot *slot = hotplug_slot->private;
 188
 189         *value = cpci_get_attention_status(slot);
 190         return 0;
 191 }
 192
 193 static int
 194 set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
 195 {
 196         return cpci_set_attention_status(hotplug_slot->private, status);
 197 }
 198
 199 static int
 200 get_adapter_status(struct hotplug_slot *hotplug_slot, u8 * value)
 201 {
 202         *value = hotplug_slot->info->adapter_status;
 203         return 0;
 204 }
 205
 206 static int
 207 get_latch_status(struct hotplug_slot *hotplug_slot, u8 * value)
 208 {
 209         *value = hotplug_slot->info->latch_status;
 210         return 0;
 211 }
 212
 213 static void release_slot(struct hotplug_slot *hotplug_slot)
 214 {
 215         struct slot *slot = hotplug_slot->private;
 216
 217         kfree(slot->hotplug_slot->info);
 218         kfree(slot->hotplug_slot->name);
 219         kfree(slot->hotplug_slot);
 220         kfree(slot);
 221 }
 222
 223 #define SLOT_NAME_SIZE  6
 224 static void
 225 make_slot_name(struct slot *slot)
 226 {
 227         snprintf(slot->hotplug_slot->name,
 228                  SLOT_NAME_SIZE, "%02x:%02x", slot->bus->number, slot->number);
 229 }
 230
 231 int
 232 cpci_hp_register_bus(struct pci_bus *bus, u8 first, u8 last)
 233 {
 234         struct slot *slot;
 235         struct hotplug_slot *hotplug_slot;
 236         struct hotplug_slot_info *info;
 237         char *name;
 238         int status = -ENOMEM;
 239         int i;
 240
 241         if (!(controller && bus))
 242                 return -ENODEV;
 243
 244         /*
 245          * Create a structure for each slot, and register that slot
 246          * with the pci_hotplug subsystem.
 247          */
 248         for (i = first; i <= last; ++i) {
 249                 slot = kmalloc(sizeof (struct slot), GFP_KERNEL);
 250                 if (!slot)
 251                         goto error;
 252                 memset(slot, 0, sizeof (struct slot));
 253
 254                 hotplug_slot =
 255                     kmalloc(sizeof (struct hotplug_slot), GFP_KERNEL);
 256                 if (!hotplug_slot)
 257                         goto error_slot;
 258                 memset(hotplug_slot, 0, sizeof (struct hotplug_slot));
 259                 slot->hotplug_slot = hotplug_slot;
 260
 261                 info = kmalloc(sizeof (struct hotplug_slot_info), GFP_KERNEL);
 262                 if (!info)
 263                         goto error_hpslot;
 264                 memset(info, 0, sizeof (struct hotplug_slot_info));
 265                 hotplug_slot->info = info;
 266
 267                 name = kmalloc(SLOT_NAME_SIZE, GFP_KERNEL);
 268                 if (!name)
 269                         goto error_info;
 270                 hotplug_slot->name = name;
 271
 272                 slot->bus = bus;
 273                 slot->number = i;
 274                 slot->devfn = PCI_DEVFN(i, 0);
 275
 276                 hotplug_slot->private = slot;
 277                 hotplug_slot->release = &release_slot;
 278                 make_slot_name(slot);
 279                 hotplug_slot->ops = &cpci_hotplug_slot_ops;
 280
 281                 /*
 282                  * Initialize the slot info structure with some known
 283                  * good values.
 284                  */
 285                 dbg("initializing slot %s", slot->hotplug_slot->name);
 286                 info->power_status = cpci_get_power_status(slot);
 287                 info->attention_status = cpci_get_attention_status(slot);
 288
 289                 dbg("registering slot %s", slot->hotplug_slot->name);
 290                 status = pci_hp_register(slot->hotplug_slot);
 291                 if (status) {
 292                         err("pci_hp_register failed with error %d", status);
 293                         goto error_name;
 294                 }
 295
 296                 /* Add slot to our internal list */
 297                 down_write(&list_rwsem);
 298                 list_add(&slot->slot_list, &slot_list);
 299                 slots++;
 300                 up_write(&list_rwsem);
 301         }
 302         return 0;
 303 error_name:
 304         kfree(name);
 305 error_info:
 306         kfree(info);
 307 error_hpslot:
 308         kfree(hotplug_slot);
 309 error_slot:
 310         kfree(slot);
 311 error:
 312         return status;
 313 }
 314
 315 int
 316 cpci_hp_unregister_bus(struct pci_bus *bus)
 317 {
 318         struct slot *slot;
 319         struct slot *tmp;
 320         int status = 0;
 321
 322         down_write(&list_rwsem);
 323         if (!slots) {
 324                 up_write(&list_rwsem);
 325                 return -1;
 326         }
 327         list_for_each_entry_safe(slot, tmp, &slot_list, slot_list) {
 328                 if (slot->bus == bus) {
 329                         list_del(&slot->slot_list);
 330                         slots--;
 331
 332                         dbg("deregistering slot %s", slot->hotplug_slot->name);
 333                         status = pci_hp_deregister(slot->hotplug_slot);
 334                         if (status) {
 335                                 err("pci_hp_deregister failed with error %d",
 336                                     status);
 337                                 break;
 338                         }
 339                 }
 340         }
 341         up_write(&list_rwsem);
 342         return status;
 343 }
 344
 345 /* This is the interrupt mode interrupt handler */
 346 static irqreturn_t
 347 cpci_hp_intr(int irq, void *data, struct pt_regs *regs)
 348 {
 349         dbg("entered cpci_hp_intr");
 350
 351         /* Check to see if it was our interrupt */
 352         if ((controller->irq_flags & SA_SHIRQ) &&
 353             !controller->ops->check_irq(controller->dev_id)) {
 354                 dbg("exited cpci_hp_intr, not our interrupt");
 355                 return IRQ_NONE;
 356         }
 357
 358         /* Disable ENUM interrupt */
 359         controller->ops->disable_irq();
 360
 361         /* Trigger processing by the event thread */
 362         dbg("Signal event_semaphore");
 363         up(&event_semaphore);
 364         dbg("exited cpci_hp_intr");
 365         return IRQ_HANDLED;
 366 }
 367
 368 /*
 369  * According to PICMG 2.1 R2.0, section 6.3.2, upon
 370  * initialization, the system driver shall clear the
 371  * INS bits of the cold-inserted devices.
 372  */
 373 static int
 374 init_slots(int clear_ins)
 375 {
 376         struct slot *slot;
 377         struct pci_dev* dev;
 378
 379         dbg("%s - enter", __FUNCTION__);
 380         down_read(&list_rwsem);
 381         if (!slots) {
 382                 up_read(&list_rwsem);
 383                 return -1;
 384         }
 385         list_for_each_entry(slot, &slot_list, slot_list) {
 386                 dbg("%s - looking at slot %s",
 387                     __FUNCTION__, slot->hotplug_slot->name);
 388                 if (clear_ins && cpci_check_and_clear_ins(slot))
 389                         dbg("%s - cleared INS for slot %s",
 390                             __FUNCTION__, slot->hotplug_slot->name);
 391                 dev = pci_get_slot(slot->bus, PCI_DEVFN(slot->number, 0));
 392                 if (dev) {
 393                         if (update_adapter_status(slot->hotplug_slot, 1))
 394                                 warn("failure to update adapter file");
 395                         if (update_latch_status(slot->hotplug_slot, 1))
 396                                 warn("failure to update latch file");
 397                         slot->dev = dev;
 398                 }
 399         }
 400         up_read(&list_rwsem);
 401         dbg("%s - exit", __FUNCTION__);
 402         return 0;
 403 }
 404
 405 static int
 406 check_slots(void)
 407 {
 408         struct slot *slot;
 409         int extracted;
 410         int inserted;
 411         u16 hs_csr;
 412
 413         down_read(&list_rwsem);
 414         if (!slots) {
 415                 up_read(&list_rwsem);
 416                 err("no slots registered, shutting down");
 417                 return -1;
 418         }
 419         extracted = inserted = 0;
 420         list_for_each_entry(slot, &slot_list, slot_list) {
 421                 dbg("%s - looking at slot %s",
 422                     __FUNCTION__, slot->hotplug_slot->name);
 423                 if (cpci_check_and_clear_ins(slot)) {
 424                         /*
 425                          * Some broken hardware (e.g. PLX 9054AB) asserts
 426                          * ENUM# twice...
 427                          */
 428                         if (slot->dev) {
 429                                 warn("slot %s already inserted",
 430                                      slot->hotplug_slot->name);
 431                                 inserted++;
 432                                 continue;
 433                         }
 434
 435                         /* Process insertion */
 436                         dbg("%s - slot %s inserted",
 437                             __FUNCTION__, slot->hotplug_slot->name);
 438
 439                         /* GSM, debug */
 440                         hs_csr = cpci_get_hs_csr(slot);
 441                         dbg("%s - slot %s HS_CSR (1) = %04x",
 442                             __FUNCTION__, slot->hotplug_slot->name, hs_csr);
 443
 444                         /* Configure device */
 445                         dbg("%s - configuring slot %s",
 446                             __FUNCTION__, slot->hotplug_slot->name);
 447                         if (cpci_configure_slot(slot)) {
 448                                 err("%s - could not configure slot %s",
 449                                     __FUNCTION__, slot->hotplug_slot->name);
 450                                 continue;
 451                         }
 452                         dbg("%s - finished configuring slot %s",
 453                             __FUNCTION__, slot->hotplug_slot->name);
 454
 455                         /* GSM, debug */
 456                         hs_csr = cpci_get_hs_csr(slot);
 457                         dbg("%s - slot %s HS_CSR (2) = %04x",
 458                             __FUNCTION__, slot->hotplug_slot->name, hs_csr);
 459
 460                         if (update_latch_status(slot->hotplug_slot, 1))
 461                                 warn("failure to update latch file");
 462
 463                         if (update_adapter_status(slot->hotplug_slot, 1))
 464                                 warn("failure to update adapter file");
 465
 466                         cpci_led_off(slot);
 467
 468                         /* GSM, debug */
 469                         hs_csr = cpci_get_hs_csr(slot);
 470                         dbg("%s - slot %s HS_CSR (3) = %04x",
 471                             __FUNCTION__, slot->hotplug_slot->name, hs_csr);
 472
 473                         inserted++;
 474                 } else if (cpci_check_ext(slot)) {
 475                         /* Process extraction request */
 476                         dbg("%s - slot %s extracted",
 477                             __FUNCTION__, slot->hotplug_slot->name);
 478
 479                         /* GSM, debug */
 480                         hs_csr = cpci_get_hs_csr(slot);
 481                         dbg("%s - slot %s HS_CSR = %04x",
 482                             __FUNCTION__, slot->hotplug_slot->name, hs_csr);
 483
 484                         if (!slot->extracting) {
 485                                 if (update_latch_status(slot->hotplug_slot, 0)) {
 486                                         warn("failure to update latch file");
 487                                 }
 488                                 slot->extracting = 1;
 489                                 atomic_inc(&extracting);
 490                         }
 491                         extracted++;
 492                 } else if (slot->extracting) {
 493                         hs_csr = cpci_get_hs_csr(slot);
 494                         if (hs_csr == 0xffff) {
 495                                 /*
 496                                  * Hmmm, we're likely hosed at this point, should we
 497                                  * bother trying to tell the driver or not?
 498                                  */
 499                                 err("card in slot %s was improperly removed",
 500                                     slot->hotplug_slot->name);
 501                                 if (update_adapter_status(slot->hotplug_slot, 0))
 502                                         warn("failure to update adapter file");
 503                                 slot->extracting = 0;
 504                                 atomic_dec(&extracting);
 505                         }
 506                 }
 507         }
 508         up_read(&list_rwsem);
 509         dbg("inserted=%d, extracted=%d, extracting=%d",
 510             inserted, extracted, atomic_read(&extracting));
 511         if (inserted || extracted)
 512                 return extracted;
 513         else if (!atomic_read(&extracting)) {
 514                 err("cannot find ENUM# source, shutting down");
 515                 return -1;
 516         }
 517         return 0;
 518 }
 519
 520 /* This is the interrupt mode worker thread body */
 521 static int
 522 event_thread(void *data)
 523 {
 524         int rc;
 525
 526         lock_kernel();
 527         daemonize("cpci_hp_eventd");
 528         unlock_kernel();
 529
 530         dbg("%s - event thread started", __FUNCTION__);
 531         while (1) {
 532                 dbg("event thread sleeping");
 533                 down_interruptible(&event_semaphore);
 534                 dbg("event thread woken, thread_finished = %d",
 535                     thread_finished);
 536                 if (thread_finished || signal_pending(current))
 537                         break;
 538                 do {
 539                         rc = check_slots();
 540                         if (rc > 0) {
 541                                 /* Give userspace a chance to handle extraction */
 542                                 msleep(500);
 543                         } else if (rc < 0) {
 544                                 dbg("%s - error checking slots", __FUNCTION__);
 545                                 thread_finished = 1;
 546                                 break;
 547                         }
 548                 } while (atomic_read(&extracting) && !thread_finished);
 549                 if (thread_finished)
 550                         break;
 551
 552                 /* Re-enable ENUM# interrupt */
 553                 dbg("%s - re-enabling irq", __FUNCTION__);
 554                 controller->ops->enable_irq();
 555         }
 556         dbg("%s - event thread signals exit", __FUNCTION__);
 557         up(&thread_exit);
 558         return 0;
 559 }
 560
 561 /* This is the polling mode worker thread body */
 562 static int
 563 poll_thread(void *data)
 564 {
 565         int rc;
 566
 567         lock_kernel();
 568         daemonize("cpci_hp_polld");
 569         unlock_kernel();
 570
 571         while (1) {
 572                 if (thread_finished || signal_pending(current))
 573                         break;
 574                 if (controller->ops->query_enum()) {
 575                         do {
 576                                 rc = check_slots();
 577                                 if (rc > 0) {
 578                                         /* Give userspace a chance to handle extraction */
 579                                         msleep(500);
 580                                 } else if (rc < 0) {
 581                                         dbg("%s - error checking slots", __FUNCTION__);
 582                                         thread_finished = 1;
 583                                         break;
 584                                 }
 585                         } while (atomic_read(&extracting) && !thread_finished);
 586                 }
 587                 msleep(100);
 588         }
 589         dbg("poll thread signals exit");
 590         up(&thread_exit);
 591         return 0;
 592 }
 593
 594 static int
 595 cpci_start_thread(void)
 596 {
 597         int pid;
 598
 599         /* initialize our semaphores */
 600         init_MUTEX_LOCKED(&event_semaphore);
 601         init_MUTEX_LOCKED(&thread_exit);
 602         thread_finished = 0;
 603
 604         if (controller->irq)
 605                 pid = kernel_thread(event_thread, NULL, 0);
 606         else
 607                 pid = kernel_thread(poll_thread, NULL, 0);
 608         if (pid < 0) {
 609                 err("Can't start up our thread");
 610                 return -1;
 611         }
 612         dbg("Our thread pid = %d", pid);
 613         return 0;
 614 }
 615
 616 static void
 617 cpci_stop_thread(void)
 618 {
 619         thread_finished = 1;
 620         dbg("thread finish command given");
 621         if (controller->irq)
 622                 up(&event_semaphore);
 623         dbg("wait for thread to exit");
 624         down(&thread_exit);
 625 }
 626
 627 int
 628 cpci_hp_register_controller(struct cpci_hp_controller *new_controller)
 629 {
 630         int status = 0;
 631
 632         if (controller)
 633                 return -1;
 634         if (!(new_controller && new_controller->ops))
 635                 return -EINVAL;
 636         if (new_controller->irq) {
 637                 if (!(new_controller->ops->enable_irq &&
 638                      new_controller->ops->disable_irq))
 639                         status = -EINVAL;
 640                 if (request_irq(new_controller->irq,
 641                                cpci_hp_intr,
 642                                new_controller->irq_flags,
 643                                MY_NAME,
 644                                new_controller->dev_id)) {
 645                         err("Can't get irq %d for the hotplug cPCI controller",
 646                             new_controller->irq);
 647                         status = -ENODEV;
 648                 }
 649                 dbg("%s - acquired controller irq %d",
 650                     __FUNCTION__, new_controller->irq);
 651         }
 652         if (!status)
 653                 controller = new_controller;
 654         return status;
 655 }
 656
 657 static void
 658 cleanup_slots(void)
 659 {
 660         struct slot *slot;
 661         struct slot *tmp;
 662
 663         /*
 664          * Unregister all of our slots with the pci_hotplug subsystem,
 665          * and free up all memory that we had allocated.
 666          */
 667         down_write(&list_rwsem);
 668         if (!slots)
 669                 goto cleanup_null;
 670         list_for_each_entry_safe(slot, tmp, &slot_list, slot_list) {
 671                 list_del(&slot->slot_list);
 672                 pci_hp_deregister(slot->hotplug_slot);
 673         }
 674 cleanup_null:
 675         up_write(&list_rwsem);
 676         return;
 677 }
 678
 679 int
 680 cpci_hp_unregister_controller(struct cpci_hp_controller *old_controller)
 681 {
 682         int status = 0;
 683
 684         if (controller) {
 685                 if (!thread_finished)
 686                         cpci_stop_thread();
 687                 if (controller->irq)
 688                         free_irq(controller->irq, controller->dev_id);
 689                 controller = NULL;
 690                 cleanup_slots();
 691         } else
 692                 status = -ENODEV;
 693         return status;
 694 }
 695
 696 int
 697 cpci_hp_start(void)
 698 {
 699         static int first = 1;
 700         int status;
 701
 702         dbg("%s - enter", __FUNCTION__);
 703         if (!controller)
 704                 return -ENODEV;
 705
 706         down_read(&list_rwsem);
 707         if (list_empty(&slot_list)) {
 708                 up_read(&list_rwsem);
 709                 return -ENODEV;
 710         }
 711         up_read(&list_rwsem);
 712
 713         status = init_slots(first);
 714         if (first)
 715                 first = 0;
 716         if (status)
 717                 return status;
 718
 719         status = cpci_start_thread();
 720         if (status)
 721                 return status;
 722         dbg("%s - thread started", __FUNCTION__);
 723
 724         if (controller->irq) {
 725                 /* Start enum interrupt processing */
 726                 dbg("%s - enabling irq", __FUNCTION__);
 727                 controller->ops->enable_irq();
 728         }
 729         dbg("%s - exit", __FUNCTION__);
 730         return 0;
 731 }
 732
 733 int
 734 cpci_hp_stop(void)
 735 {
 736         if (!controller)
 737                 return -ENODEV;
 738         if (controller->irq) {
 739                 /* Stop enum interrupt processing */
 740                 dbg("%s - disabling irq", __FUNCTION__);
 741                 controller->ops->disable_irq();
 742         }
 743         cpci_stop_thread();
 744         return 0;
 745 }
 746
 747 int __init
 748 cpci_hotplug_init(int debug)
 749 {
 750         cpci_debug = debug;
 751         return 0;
 752 }
 753
 754 void __exit
 755 cpci_hotplug_exit(void)
 756 {
 757         /*
 758          * Clean everything up.
 759          */
 760         cpci_hp_stop();
 761         cpci_hp_unregister_controller(controller);
 762 }
 763
 764 EXPORT_SYMBOL_GPL(cpci_hp_register_controller);
 765 EXPORT_SYMBOL_GPL(cpci_hp_unregister_controller);
 766 EXPORT_SYMBOL_GPL(cpci_hp_register_bus);
 767 EXPORT_SYMBOL_GPL(cpci_hp_unregister_bus);
 768 EXPORT_SYMBOL_GPL(cpci_hp_start);
 769 EXPORT_SYMBOL_GPL(cpci_hp_stop);