drivers/pci/hotplug/pci_hotplug_core.c

   1 /*
   2  * PCI HotPlug Controller Core
   3  *
   4  * Copyright (C) 2001-2002 Greg Kroah-Hartman (greg@kroah.com)
   5  * Copyright (C) 2001-2002 IBM Corp.
   6  *
   7  * All rights reserved.
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or (at
  12  * your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful, but
  15  * WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  17  * NON INFRINGEMENT.  See the GNU General Public License for more
  18  * details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  23  *
  24  * Send feedback to <kristen.c.accardi@intel.com>
  25  *
  26  */
  27
  28 #include <linux/module.h>
  29 #include <linux/moduleparam.h>
  30 #include <linux/kernel.h>
  31 #include <linux/types.h>
  32 #include <linux/list.h>
  33 #include <linux/kobject.h>
  34 #include <linux/sysfs.h>
  35 #include <linux/pagemap.h>
  36 #include <linux/slab.h>
  37 #include <linux/init.h>
  38 #include <linux/mount.h>
  39 #include <linux/namei.h>
  40 #include <linux/pci.h>
  41 #include <linux/pci_hotplug.h>
  42 #include <asm/uaccess.h>
  43
  44 #define MY_NAME "pci_hotplug"
  45
  46 #define dbg(fmt, arg...) do { if (debug) printk(KERN_DEBUG "%s: %s: " fmt , MY_NAME , __FUNCTION__ , ## arg); } while (0)
  47 #define err(format, arg...) printk(KERN_ERR "%s: " format , MY_NAME , ## arg)
  48 #define info(format, arg...) printk(KERN_INFO "%s: " format , MY_NAME , ## arg)
  49 #define warn(format, arg...) printk(KERN_WARNING "%s: " format , MY_NAME , ## arg)
  50
  51
  52 /* local variables */
  53 static int debug;
  54
  55 #define DRIVER_VERSION  "0.5"
  56 #define DRIVER_AUTHOR   "Greg Kroah-Hartman <greg@kroah.com>, Scott Murray <scottm@somanetworks.com>"
  57 #define DRIVER_DESC     "PCI Hot Plug PCI Core"
  58
  59
  60 //////////////////////////////////////////////////////////////////
  61
  62 static LIST_HEAD(pci_hotplug_slot_list);
  63
  64 struct kset *pci_hotplug_slots_kset;
  65
  66 static ssize_t hotplug_slot_attr_show(struct kobject *kobj,
  67                 struct attribute *attr, char *buf)
  68 {
  69         struct hotplug_slot *slot = to_hotplug_slot(kobj);
  70         struct hotplug_slot_attribute *attribute = to_hotplug_attr(attr);
  71         return attribute->show ? attribute->show(slot, buf) : -EIO;
  72 }
  73
  74 static ssize_t hotplug_slot_attr_store(struct kobject *kobj,
  75                 struct attribute *attr, const char *buf, size_t len)
  76 {
  77         struct hotplug_slot *slot = to_hotplug_slot(kobj);
  78         struct hotplug_slot_attribute *attribute = to_hotplug_attr(attr);
  79         return attribute->store ? attribute->store(slot, buf, len) : -EIO;
  80 }
  81
  82 static struct sysfs_ops hotplug_slot_sysfs_ops = {
  83         .show = hotplug_slot_attr_show,
  84         .store = hotplug_slot_attr_store,
  85 };
  86
  87 static void hotplug_slot_release(struct kobject *kobj)
  88 {
  89         struct hotplug_slot *slot = to_hotplug_slot(kobj);
  90         if (slot->release)
  91                 slot->release(slot);
  92 }
  93
  94 static struct kobj_type hotplug_slot_ktype = {
  95         .sysfs_ops = &hotplug_slot_sysfs_ops,
  96         .release = &hotplug_slot_release,
  97 };
  98
  99 /* these strings match up with the values in pci_bus_speed */
 100 static char *pci_bus_speed_strings[] = {
 101         "33 MHz PCI",           /* 0x00 */
 102         "66 MHz PCI",           /* 0x01 */
 103         "66 MHz PCIX",          /* 0x02 */
 104         "100 MHz PCIX",         /* 0x03 */
 105         "133 MHz PCIX",         /* 0x04 */
 106         NULL,                   /* 0x05 */
 107         NULL,                   /* 0x06 */
 108         NULL,                   /* 0x07 */
 109         NULL,                   /* 0x08 */
 110         "66 MHz PCIX 266",      /* 0x09 */
 111         "100 MHz PCIX 266",     /* 0x0a */
 112         "133 MHz PCIX 266",     /* 0x0b */
 113         NULL,                   /* 0x0c */
 114         NULL,                   /* 0x0d */
 115         NULL,                   /* 0x0e */
 116         NULL,                   /* 0x0f */
 117         NULL,                   /* 0x10 */
 118         "66 MHz PCIX 533",      /* 0x11 */
 119         "100 MHz PCIX 533",     /* 0x12 */
 120         "133 MHz PCIX 533",     /* 0x13 */
 121         "25 GBps PCI-E",        /* 0x14 */
 122 };
 123
 124 #ifdef CONFIG_HOTPLUG_PCI_CPCI
 125 extern int cpci_hotplug_init(int debug);
 126 extern void cpci_hotplug_exit(void);
 127 #else
 128 static inline int cpci_hotplug_init(int debug) { return 0; }
 129 static inline void cpci_hotplug_exit(void) { }
 130 #endif
 131
 132 /* Weee, fun with macros... */
 133 #define GET_STATUS(name,type)   \
 134 static int get_##name (struct hotplug_slot *slot, type *value)          \
 135 {                                                                       \
 136         struct hotplug_slot_ops *ops = slot->ops;                       \
 137         int retval = 0;                                                 \
 138         if (try_module_get(ops->owner)) {                               \
 139                 if (ops->get_##name)                                    \
 140                         retval = ops->get_##name (slot, value);         \
 141                 else                                                    \
 142                         *value = slot->info->name;                      \
 143                 module_put(ops->owner);                                 \
 144         }                                                               \
 145         return retval;                                                  \
 146 }
 147
 148 GET_STATUS(power_status, u8)
 149 GET_STATUS(attention_status, u8)
 150 GET_STATUS(latch_status, u8)
 151 GET_STATUS(adapter_status, u8)
 152 GET_STATUS(address, u32)
 153 GET_STATUS(max_bus_speed, enum pci_bus_speed)
 154 GET_STATUS(cur_bus_speed, enum pci_bus_speed)
 155
 156 static ssize_t power_read_file (struct hotplug_slot *slot, char *buf)
 157 {
 158         int retval;
 159         u8 value;
 160
 161         retval = get_power_status (slot, &value);
 162         if (retval)
 163                 goto exit;
 164         retval = sprintf (buf, "%d\n", value);
 165 exit:
 166         return retval;
 167 }
 168
 169 static ssize_t power_write_file (struct hotplug_slot *slot, const char *buf,
 170                 size_t count)
 171 {
 172         unsigned long lpower;
 173         u8 power;
 174         int retval = 0;
 175
 176         lpower = simple_strtoul (buf, NULL, 10);
 177         power = (u8)(lpower & 0xff);
 178         dbg ("power = %d\n", power);
 179
 180         if (!try_module_get(slot->ops->owner)) {
 181                 retval = -ENODEV;
 182                 goto exit;
 183         }
 184         switch (power) {
 185                 case 0:
 186                         if (slot->ops->disable_slot)
 187                                 retval = slot->ops->disable_slot(slot);
 188                         break;
 189
 190                 case 1:
 191                         if (slot->ops->enable_slot)
 192                                 retval = slot->ops->enable_slot(slot);
 193                         break;
 194
 195                 default:
 196                         err ("Illegal value specified for power\n");
 197                         retval = -EINVAL;
 198         }
 199         module_put(slot->ops->owner);
 200
 201 exit:
 202         if (retval)
 203                 return retval;
 204         return count;
 205 }
 206
 207 static struct hotplug_slot_attribute hotplug_slot_attr_power = {
 208         .attr = {.name = "power", .mode = S_IFREG | S_IRUGO | S_IWUSR},
 209         .show = power_read_file,
 210         .store = power_write_file
 211 };
 212
 213 static ssize_t attention_read_file (struct hotplug_slot *slot, char *buf)
 214 {
 215         int retval;
 216         u8 value;
 217
 218         retval = get_attention_status (slot, &value);
 219         if (retval)
 220                 goto exit;
 221         retval = sprintf (buf, "%d\n", value);
 222
 223 exit:
 224         return retval;
 225 }
 226
 227 static ssize_t attention_write_file (struct hotplug_slot *slot, const char *buf,
 228                 size_t count)
 229 {
 230         unsigned long lattention;
 231         u8 attention;
 232         int retval = 0;
 233
 234         lattention = simple_strtoul (buf, NULL, 10);
 235         attention = (u8)(lattention & 0xff);
 236         dbg (" - attention = %d\n", attention);
 237
 238         if (!try_module_get(slot->ops->owner)) {
 239                 retval = -ENODEV;
 240                 goto exit;
 241         }
 242         if (slot->ops->set_attention_status)
 243                 retval = slot->ops->set_attention_status(slot, attention);
 244         module_put(slot->ops->owner);
 245
 246 exit:
 247         if (retval)
 248                 return retval;
 249         return count;
 250 }
 251
 252 static struct hotplug_slot_attribute hotplug_slot_attr_attention = {
 253         .attr = {.name = "attention", .mode = S_IFREG | S_IRUGO | S_IWUSR},
 254         .show = attention_read_file,
 255         .store = attention_write_file
 256 };
 257
 258 static ssize_t latch_read_file (struct hotplug_slot *slot, char *buf)
 259 {
 260         int retval;
 261         u8 value;
 262
 263         retval = get_latch_status (slot, &value);
 264         if (retval)
 265                 goto exit;
 266         retval = sprintf (buf, "%d\n", value);
 267
 268 exit:
 269         return retval;
 270 }
 271
 272 static struct hotplug_slot_attribute hotplug_slot_attr_latch = {
 273         .attr = {.name = "latch", .mode = S_IFREG | S_IRUGO},
 274         .show = latch_read_file,
 275 };
 276
 277 static ssize_t presence_read_file (struct hotplug_slot *slot, char *buf)
 278 {
 279         int retval;
 280         u8 value;
 281
 282         retval = get_adapter_status (slot, &value);
 283         if (retval)
 284                 goto exit;
 285         retval = sprintf (buf, "%d\n", value);
 286
 287 exit:
 288         return retval;
 289 }
 290
 291 static struct hotplug_slot_attribute hotplug_slot_attr_presence = {
 292         .attr = {.name = "adapter", .mode = S_IFREG | S_IRUGO},
 293         .show = presence_read_file,
 294 };
 295
 296 static ssize_t address_read_file (struct hotplug_slot *slot, char *buf)
 297 {
 298         int retval;
 299         u32 address;
 300
 301         retval = get_address (slot, &address);
 302         if (retval)
 303                 goto exit;
 304         retval = sprintf (buf, "%04x:%02x:%02x\n",
 305                           (address >> 16) & 0xffff,
 306                           (address >> 8) & 0xff,
 307                           address & 0xff);
 308
 309 exit:
 310         return retval;
 311 }
 312
 313 static struct hotplug_slot_attribute hotplug_slot_attr_address = {
 314         .attr = {.name = "address", .mode = S_IFREG | S_IRUGO},
 315         .show = address_read_file,
 316 };
 317
 318 static char *unknown_speed = "Unknown bus speed";
 319
 320 static ssize_t max_bus_speed_read_file (struct hotplug_slot *slot, char *buf)
 321 {
 322         char *speed_string;
 323         int retval;
 324         enum pci_bus_speed value;
 325
 326         retval = get_max_bus_speed (slot, &value);
 327         if (retval)
 328                 goto exit;
 329
 330         if (value == PCI_SPEED_UNKNOWN)
 331                 speed_string = unknown_speed;
 332         else
 333                 speed_string = pci_bus_speed_strings[value];
 334
 335         retval = sprintf (buf, "%s\n", speed_string);
 336
 337 exit:
 338         return retval;
 339 }
 340
 341 static struct hotplug_slot_attribute hotplug_slot_attr_max_bus_speed = {
 342         .attr = {.name = "max_bus_speed", .mode = S_IFREG | S_IRUGO},
 343         .show = max_bus_speed_read_file,
 344 };
 345
 346 static ssize_t cur_bus_speed_read_file (struct hotplug_slot *slot, char *buf)
 347 {
 348         char *speed_string;
 349         int retval;
 350         enum pci_bus_speed value;
 351
 352         retval = get_cur_bus_speed (slot, &value);
 353         if (retval)
 354                 goto exit;
 355
 356         if (value == PCI_SPEED_UNKNOWN)
 357                 speed_string = unknown_speed;
 358         else
 359                 speed_string = pci_bus_speed_strings[value];
 360
 361         retval = sprintf (buf, "%s\n", speed_string);
 362
 363 exit:
 364         return retval;
 365 }
 366
 367 static struct hotplug_slot_attribute hotplug_slot_attr_cur_bus_speed = {
 368         .attr = {.name = "cur_bus_speed", .mode = S_IFREG | S_IRUGO},
 369         .show = cur_bus_speed_read_file,
 370 };
 371
 372 static ssize_t test_write_file (struct hotplug_slot *slot, const char *buf,
 373                 size_t count)
 374 {
 375         unsigned long ltest;
 376         u32 test;
 377         int retval = 0;
 378
 379         ltest = simple_strtoul (buf, NULL, 10);
 380         test = (u32)(ltest & 0xffffffff);
 381         dbg ("test = %d\n", test);
 382
 383         if (!try_module_get(slot->ops->owner)) {
 384                 retval = -ENODEV;
 385                 goto exit;
 386         }
 387         if (slot->ops->hardware_test)
 388                 retval = slot->ops->hardware_test(slot, test);
 389         module_put(slot->ops->owner);
 390
 391 exit:
 392         if (retval)
 393                 return retval;
 394         return count;
 395 }
 396
 397 static struct hotplug_slot_attribute hotplug_slot_attr_test = {
 398         .attr = {.name = "test", .mode = S_IFREG | S_IRUGO | S_IWUSR},
 399         .store = test_write_file
 400 };
 401
 402 static int has_power_file (struct hotplug_slot *slot)
 403 {
 404         if ((!slot) || (!slot->ops))
 405                 return -ENODEV;
 406         if ((slot->ops->enable_slot) ||
 407             (slot->ops->disable_slot) ||
 408             (slot->ops->get_power_status))
 409                 return 0;
 410         return -ENOENT;
 411 }
 412
 413 static int has_attention_file (struct hotplug_slot *slot)
 414 {
 415         if ((!slot) || (!slot->ops))
 416                 return -ENODEV;
 417         if ((slot->ops->set_attention_status) ||
 418             (slot->ops->get_attention_status))
 419                 return 0;
 420         return -ENOENT;
 421 }
 422
 423 static int has_latch_file (struct hotplug_slot *slot)
 424 {
 425         if ((!slot) || (!slot->ops))
 426                 return -ENODEV;
 427         if (slot->ops->get_latch_status)
 428                 return 0;
 429         return -ENOENT;
 430 }
 431
 432 static int has_adapter_file (struct hotplug_slot *slot)
 433 {
 434         if ((!slot) || (!slot->ops))
 435                 return -ENODEV;
 436         if (slot->ops->get_adapter_status)
 437                 return 0;
 438         return -ENOENT;
 439 }
 440
 441 static int has_address_file (struct hotplug_slot *slot)
 442 {
 443         if ((!slot) || (!slot->ops))
 444                 return -ENODEV;
 445         if (slot->ops->get_address)
 446                 return 0;
 447         return -ENOENT;
 448 }
 449
 450 static int has_max_bus_speed_file (struct hotplug_slot *slot)
 451 {
 452         if ((!slot) || (!slot->ops))
 453                 return -ENODEV;
 454         if (slot->ops->get_max_bus_speed)
 455                 return 0;
 456         return -ENOENT;
 457 }
 458
 459 static int has_cur_bus_speed_file (struct hotplug_slot *slot)
 460 {
 461         if ((!slot) || (!slot->ops))
 462                 return -ENODEV;
 463         if (slot->ops->get_cur_bus_speed)
 464                 return 0;
 465         return -ENOENT;
 466 }
 467
 468 static int has_test_file (struct hotplug_slot *slot)
 469 {
 470         if ((!slot) || (!slot->ops))
 471                 return -ENODEV;
 472         if (slot->ops->hardware_test)
 473                 return 0;
 474         return -ENOENT;
 475 }
 476
 477 static int fs_add_slot (struct hotplug_slot *slot)
 478 {
 479         int retval = 0;
 480
 481         if (has_power_file(slot) == 0) {
 482                 retval = sysfs_create_file(&slot->kobj, &hotplug_slot_attr_power.attr);
 483                 if (retval)
 484                         goto exit_power;
 485         }
 486
 487         if (has_attention_file(slot) == 0) {
 488                 retval = sysfs_create_file(&slot->kobj,
 489                                            &hotplug_slot_attr_attention.attr);
 490                 if (retval)
 491                         goto exit_attention;
 492         }
 493
 494         if (has_latch_file(slot) == 0) {
 495                 retval = sysfs_create_file(&slot->kobj,
 496                                            &hotplug_slot_attr_latch.attr);
 497                 if (retval)
 498                         goto exit_latch;
 499         }
 500
 501         if (has_adapter_file(slot) == 0) {
 502                 retval = sysfs_create_file(&slot->kobj,
 503                                            &hotplug_slot_attr_presence.attr);
 504                 if (retval)
 505                         goto exit_adapter;
 506         }
 507
 508         if (has_address_file(slot) == 0) {
 509                 retval = sysfs_create_file(&slot->kobj,
 510                                            &hotplug_slot_attr_address.attr);
 511                 if (retval)
 512                         goto exit_address;
 513         }
 514
 515         if (has_max_bus_speed_file(slot) == 0) {
 516                 retval = sysfs_create_file(&slot->kobj,
 517                                            &hotplug_slot_attr_max_bus_speed.attr);
 518                 if (retval)
 519                         goto exit_max_speed;
 520         }
 521
 522         if (has_cur_bus_speed_file(slot) == 0) {
 523                 retval = sysfs_create_file(&slot->kobj,
 524                                            &hotplug_slot_attr_cur_bus_speed.attr);
 525                 if (retval)
 526                         goto exit_cur_speed;
 527         }
 528
 529         if (has_test_file(slot) == 0) {
 530                 retval = sysfs_create_file(&slot->kobj,
 531                                            &hotplug_slot_attr_test.attr);
 532                 if (retval)
 533                         goto exit_test;
 534         }
 535
 536         goto exit;
 537
 538 exit_test:
 539         if (has_cur_bus_speed_file(slot) == 0)
 540                 sysfs_remove_file(&slot->kobj, &hotplug_slot_attr_cur_bus_speed.attr);
 541
 542 exit_cur_speed:
 543         if (has_max_bus_speed_file(slot) == 0)
 544                 sysfs_remove_file(&slot->kobj, &hotplug_slot_attr_max_bus_speed.attr);
 545
 546 exit_max_speed:
 547         if (has_address_file(slot) == 0)
 548                 sysfs_remove_file(&slot->kobj, &hotplug_slot_attr_address.attr);
 549
 550 exit_address:
 551         if (has_adapter_file(slot) == 0)
 552                 sysfs_remove_file(&slot->kobj, &hotplug_slot_attr_presence.attr);
 553
 554 exit_adapter:
 555         if (has_latch_file(slot) == 0)
 556                 sysfs_remove_file(&slot->kobj, &hotplug_slot_attr_latch.attr);
 557
 558 exit_latch:
 559         if (has_attention_file(slot) == 0)
 560                 sysfs_remove_file(&slot->kobj, &hotplug_slot_attr_attention.attr);
 561
 562 exit_attention:
 563         if (has_power_file(slot) == 0)
 564                 sysfs_remove_file(&slot->kobj, &hotplug_slot_attr_power.attr);
 565 exit_power:
 566 exit:
 567         return retval;
 568 }
 569
 570 static void fs_remove_slot (struct hotplug_slot *slot)
 571 {
 572         if (has_power_file(slot) == 0)
 573                 sysfs_remove_file(&slot->kobj, &hotplug_slot_attr_power.attr);
 574
 575         if (has_attention_file(slot) == 0)
 576                 sysfs_remove_file(&slot->kobj, &hotplug_slot_attr_attention.attr);
 577
 578         if (has_latch_file(slot) == 0)
 579                 sysfs_remove_file(&slot->kobj, &hotplug_slot_attr_latch.attr);
 580
 581         if (has_adapter_file(slot) == 0)
 582                 sysfs_remove_file(&slot->kobj, &hotplug_slot_attr_presence.attr);
 583
 584         if (has_address_file(slot) == 0)
 585                 sysfs_remove_file(&slot->kobj, &hotplug_slot_attr_address.attr);
 586
 587         if (has_max_bus_speed_file(slot) == 0)
 588                 sysfs_remove_file(&slot->kobj, &hotplug_slot_attr_max_bus_speed.attr);
 589
 590         if (has_cur_bus_speed_file(slot) == 0)
 591                 sysfs_remove_file(&slot->kobj, &hotplug_slot_attr_cur_bus_speed.attr);
 592
 593         if (has_test_file(slot) == 0)
 594                 sysfs_remove_file(&slot->kobj, &hotplug_slot_attr_test.attr);
 595 }
 596
 597 static struct hotplug_slot *get_slot_from_name (const char *name)
 598 {
 599         struct hotplug_slot *slot;
 600         struct list_head *tmp;
 601
 602         list_for_each (tmp, &pci_hotplug_slot_list) {
 603                 slot = list_entry (tmp, struct hotplug_slot, slot_list);
 604                 if (strcmp(slot->name, name) == 0)
 605                         return slot;
 606         }
 607         return NULL;
 608 }
 609
 610 /**
 611  * pci_hp_register - register a hotplug_slot with the PCI hotplug subsystem
 612  * @slot: pointer to the &struct hotplug_slot to register
 613  *
 614  * Registers a hotplug slot with the pci hotplug subsystem, which will allow
 615  * userspace interaction to the slot.
 616  *
 617  * Returns 0 if successful, anything else for an error.
 618  */
 619 int pci_hp_register (struct hotplug_slot *slot)
 620 {
 621         int result;
 622
 623         if (slot == NULL)
 624                 return -ENODEV;
 625         if ((slot->info == NULL) || (slot->ops == NULL))
 626                 return -EINVAL;
 627         if (slot->release == NULL) {
 628                 dbg("Why are you trying to register a hotplug slot"
 629                     "without a proper release function?\n");
 630                 return -EINVAL;
 631         }
 632
 633         kobject_set_name(&slot->kobj, "%s", slot->name);
 634         slot->kobj.kset = pci_hotplug_slots_kset;
 635         slot->kobj.ktype = &hotplug_slot_ktype;
 636
 637         /* this can fail if we have already registered a slot with the same name */
 638         if (kobject_register(&slot->kobj)) {
 639                 err("Unable to register kobject");
 640                 return -EINVAL;
 641         }
 642
 643         list_add (&slot->slot_list, &pci_hotplug_slot_list);
 644
 645         result = fs_add_slot (slot);
 646         dbg ("Added slot %s to the list\n", slot->name);
 647         return result;
 648 }
 649
 650 /**
 651  * pci_hp_deregister - deregister a hotplug_slot with the PCI hotplug subsystem
 652  * @slot: pointer to the &struct hotplug_slot to deregister
 653  *
 654  * The @slot must have been registered with the pci hotplug subsystem
 655  * previously with a call to pci_hp_register().
 656  *
 657  * Returns 0 if successful, anything else for an error.
 658  */
 659 int pci_hp_deregister (struct hotplug_slot *slot)
 660 {
 661         struct hotplug_slot *temp;
 662
 663         if (slot == NULL)
 664                 return -ENODEV;
 665
 666         temp = get_slot_from_name (slot->name);
 667         if (temp != slot) {
 668                 return -ENODEV;
 669         }
 670         list_del (&slot->slot_list);
 671
 672         fs_remove_slot (slot);
 673         dbg ("Removed slot %s from the list\n", slot->name);
 674         kobject_unregister(&slot->kobj);
 675         return 0;
 676 }
 677
 678 /**
 679  * pci_hp_change_slot_info - changes the slot's information structure in the core
 680  * @slot: pointer to the slot whose info has changed
 681  * @info: pointer to the info copy into the slot's info structure
 682  *
 683  * @slot must have been registered with the pci
 684  * hotplug subsystem previously with a call to pci_hp_register().
 685  *
 686  * Returns 0 if successful, anything else for an error.
 687  */
 688 int __must_check pci_hp_change_slot_info(struct hotplug_slot *slot,
 689                                          struct hotplug_slot_info *info)
 690 {
 691         if ((slot == NULL) || (info == NULL))
 692                 return -ENODEV;
 693
 694         memcpy (slot->info, info, sizeof (struct hotplug_slot_info));
 695
 696         return 0;
 697 }
 698
 699 static int __init pci_hotplug_init (void)
 700 {
 701         int result;
 702
 703         pci_hotplug_slots_kset = kset_create_and_add("slots", NULL,
 704                                                      &pci_bus_type.subsys.kobj);
 705         if (!pci_hotplug_slots_kset) {
 706                 result = -ENOMEM;
 707                 err("Register subsys error\n");
 708                 goto exit;
 709         }
 710         result = cpci_hotplug_init(debug);
 711         if (result) {
 712                 err ("cpci_hotplug_init with error %d\n", result);
 713                 goto err_subsys;
 714         }
 715
 716         info (DRIVER_DESC " version: " DRIVER_VERSION "\n");
 717         goto exit;
 718
 719 err_subsys:
 720         kset_unregister(pci_hotplug_slots_kset);
 721 exit:
 722         return result;
 723 }
 724
 725 static void __exit pci_hotplug_exit (void)
 726 {
 727         cpci_hotplug_exit();
 728         kset_unregister(pci_hotplug_slots_kset);
 729 }
 730
 731 module_init(pci_hotplug_init);
 732 module_exit(pci_hotplug_exit);
 733
 734 MODULE_AUTHOR(DRIVER_AUTHOR);
 735 MODULE_DESCRIPTION(DRIVER_DESC);
 736 MODULE_LICENSE("GPL");
 737 module_param(debug, bool, 0644);
 738 MODULE_PARM_DESC(debug, "Debugging mode enabled or not");
 739
 740 EXPORT_SYMBOL_GPL(pci_hotplug_slots_kset);
 741 EXPORT_SYMBOL_GPL(pci_hp_register);
 742 EXPORT_SYMBOL_GPL(pci_hp_deregister);
 743 EXPORT_SYMBOL_GPL(pci_hp_change_slot_info);