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> /* try_module_get & module_put */ 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/init.h> 37 #include <linux/mount.h> 38 #include <linux/namei.h> 39 #include <linux/mutex.h> 40 #include <linux/pci.h> 41 #include <linux/pci_hotplug.h> 42 #include <asm/uaccess.h> 43 #include "../pci.h" 44 #include "cpci_hotplug.h" 45 46 #define MY_NAME "pci_hotplug" 47 48 #define dbg(fmt, arg...) do { if (debug) printk(KERN_DEBUG "%s: %s: " fmt, MY_NAME, __func__, ## arg); } while (0) 49 #define err(format, arg...) printk(KERN_ERR "%s: " format, MY_NAME, ## arg) 50 #define info(format, arg...) printk(KERN_INFO "%s: " format, MY_NAME, ## arg) 51 #define warn(format, arg...) printk(KERN_WARNING "%s: " format, MY_NAME, ## arg) 52 53 54 /* local variables */ 55 static bool debug; 56 57 #define DRIVER_VERSION "0.5" 58 #define DRIVER_AUTHOR "Greg Kroah-Hartman <greg@kroah.com>, Scott Murray <scottm@somanetworks.com>" 59 #define DRIVER_DESC "PCI Hot Plug PCI Core" 60 61 62 static LIST_HEAD(pci_hotplug_slot_list); 63 static DEFINE_MUTEX(pci_hp_mutex); 64 65 /* Weee, fun with macros... */ 66 #define GET_STATUS(name, type) \ 67 static int get_##name(struct hotplug_slot *slot, type *value) \ 68 { \ 69 struct hotplug_slot_ops *ops = slot->ops; \ 70 int retval = 0; \ 71 if (!try_module_get(ops->owner)) \ 72 return -ENODEV; \ 73 if (ops->get_##name) \ 74 retval = ops->get_##name(slot, value); \ 75 else \ 76 *value = slot->info->name; \ 77 module_put(ops->owner); \ 78 return retval; \ 79 } 80 81 GET_STATUS(power_status, u8) 82 GET_STATUS(attention_status, u8) 83 GET_STATUS(latch_status, u8) 84 GET_STATUS(adapter_status, u8) 85 86 static ssize_t power_read_file(struct pci_slot *pci_slot, char *buf) 87 { 88 int retval; 89 u8 value; 90 91 retval = get_power_status(pci_slot->hotplug, &value); 92 if (retval) 93 return retval; 94 95 return sprintf(buf, "%d\n", value); 96 } 97 98 static ssize_t power_write_file(struct pci_slot *pci_slot, const char *buf, 99 size_t count) 100 { 101 struct hotplug_slot *slot = pci_slot->hotplug; 102 unsigned long lpower; 103 u8 power; 104 int retval = 0; 105 106 lpower = simple_strtoul(buf, NULL, 10); 107 power = (u8)(lpower & 0xff); 108 dbg("power = %d\n", power); 109 110 if (!try_module_get(slot->ops->owner)) { 111 retval = -ENODEV; 112 goto exit; 113 } 114 switch (power) { 115 case 0: 116 if (slot->ops->disable_slot) 117 retval = slot->ops->disable_slot(slot); 118 break; 119 120 case 1: 121 if (slot->ops->enable_slot) 122 retval = slot->ops->enable_slot(slot); 123 break; 124 125 default: 126 err("Illegal value specified for power\n"); 127 retval = -EINVAL; 128 } 129 module_put(slot->ops->owner); 130 131 exit: 132 if (retval) 133 return retval; 134 return count; 135 } 136 137 static struct pci_slot_attribute hotplug_slot_attr_power = { 138 .attr = {.name = "power", .mode = S_IFREG | S_IRUGO | S_IWUSR}, 139 .show = power_read_file, 140 .store = power_write_file 141 }; 142 143 static ssize_t attention_read_file(struct pci_slot *pci_slot, char *buf) 144 { 145 int retval; 146 u8 value; 147 148 retval = get_attention_status(pci_slot->hotplug, &value); 149 if (retval) 150 return retval; 151 152 return sprintf(buf, "%d\n", value); 153 } 154 155 static ssize_t attention_write_file(struct pci_slot *pci_slot, const char *buf, 156 size_t count) 157 { 158 struct hotplug_slot_ops *ops = pci_slot->hotplug->ops; 159 unsigned long lattention; 160 u8 attention; 161 int retval = 0; 162 163 lattention = simple_strtoul(buf, NULL, 10); 164 attention = (u8)(lattention & 0xff); 165 dbg(" - attention = %d\n", attention); 166 167 if (!try_module_get(ops->owner)) { 168 retval = -ENODEV; 169 goto exit; 170 } 171 if (ops->set_attention_status) 172 retval = ops->set_attention_status(pci_slot->hotplug, attention); 173 module_put(ops->owner); 174 175 exit: 176 if (retval) 177 return retval; 178 return count; 179 } 180 181 static struct pci_slot_attribute hotplug_slot_attr_attention = { 182 .attr = {.name = "attention", .mode = S_IFREG | S_IRUGO | S_IWUSR}, 183 .show = attention_read_file, 184 .store = attention_write_file 185 }; 186 187 static ssize_t latch_read_file(struct pci_slot *pci_slot, char *buf) 188 { 189 int retval; 190 u8 value; 191 192 retval = get_latch_status(pci_slot->hotplug, &value); 193 if (retval) 194 return retval; 195 196 return sprintf(buf, "%d\n", value); 197 } 198 199 static struct pci_slot_attribute hotplug_slot_attr_latch = { 200 .attr = {.name = "latch", .mode = S_IFREG | S_IRUGO}, 201 .show = latch_read_file, 202 }; 203 204 static ssize_t presence_read_file(struct pci_slot *pci_slot, char *buf) 205 { 206 int retval; 207 u8 value; 208 209 retval = get_adapter_status(pci_slot->hotplug, &value); 210 if (retval) 211 return retval; 212 213 return sprintf(buf, "%d\n", value); 214 } 215 216 static struct pci_slot_attribute hotplug_slot_attr_presence = { 217 .attr = {.name = "adapter", .mode = S_IFREG | S_IRUGO}, 218 .show = presence_read_file, 219 }; 220 221 static ssize_t test_write_file(struct pci_slot *pci_slot, const char *buf, 222 size_t count) 223 { 224 struct hotplug_slot *slot = pci_slot->hotplug; 225 unsigned long ltest; 226 u32 test; 227 int retval = 0; 228 229 ltest = simple_strtoul(buf, NULL, 10); 230 test = (u32)(ltest & 0xffffffff); 231 dbg("test = %d\n", test); 232 233 if (!try_module_get(slot->ops->owner)) { 234 retval = -ENODEV; 235 goto exit; 236 } 237 if (slot->ops->hardware_test) 238 retval = slot->ops->hardware_test(slot, test); 239 module_put(slot->ops->owner); 240 241 exit: 242 if (retval) 243 return retval; 244 return count; 245 } 246 247 static struct pci_slot_attribute hotplug_slot_attr_test = { 248 .attr = {.name = "test", .mode = S_IFREG | S_IRUGO | S_IWUSR}, 249 .store = test_write_file 250 }; 251 252 static bool has_power_file(struct pci_slot *pci_slot) 253 { 254 struct hotplug_slot *slot = pci_slot->hotplug; 255 256 if ((!slot) || (!slot->ops)) 257 return false; 258 if ((slot->ops->enable_slot) || 259 (slot->ops->disable_slot) || 260 (slot->ops->get_power_status)) 261 return true; 262 return false; 263 } 264 265 static bool has_attention_file(struct pci_slot *pci_slot) 266 { 267 struct hotplug_slot *slot = pci_slot->hotplug; 268 269 if ((!slot) || (!slot->ops)) 270 return false; 271 if ((slot->ops->set_attention_status) || 272 (slot->ops->get_attention_status)) 273 return true; 274 return false; 275 } 276 277 static bool has_latch_file(struct pci_slot *pci_slot) 278 { 279 struct hotplug_slot *slot = pci_slot->hotplug; 280 281 if ((!slot) || (!slot->ops)) 282 return false; 283 if (slot->ops->get_latch_status) 284 return true; 285 return false; 286 } 287 288 static bool has_adapter_file(struct pci_slot *pci_slot) 289 { 290 struct hotplug_slot *slot = pci_slot->hotplug; 291 292 if ((!slot) || (!slot->ops)) 293 return false; 294 if (slot->ops->get_adapter_status) 295 return true; 296 return false; 297 } 298 299 static bool has_test_file(struct pci_slot *pci_slot) 300 { 301 struct hotplug_slot *slot = pci_slot->hotplug; 302 303 if ((!slot) || (!slot->ops)) 304 return false; 305 if (slot->ops->hardware_test) 306 return true; 307 return false; 308 } 309 310 static int fs_add_slot(struct pci_slot *pci_slot) 311 { 312 int retval = 0; 313 314 /* Create symbolic link to the hotplug driver module */ 315 pci_hp_create_module_link(pci_slot); 316 317 if (has_power_file(pci_slot)) { 318 retval = sysfs_create_file(&pci_slot->kobj, 319 &hotplug_slot_attr_power.attr); 320 if (retval) 321 goto exit_power; 322 } 323 324 if (has_attention_file(pci_slot)) { 325 retval = sysfs_create_file(&pci_slot->kobj, 326 &hotplug_slot_attr_attention.attr); 327 if (retval) 328 goto exit_attention; 329 } 330 331 if (has_latch_file(pci_slot)) { 332 retval = sysfs_create_file(&pci_slot->kobj, 333 &hotplug_slot_attr_latch.attr); 334 if (retval) 335 goto exit_latch; 336 } 337 338 if (has_adapter_file(pci_slot)) { 339 retval = sysfs_create_file(&pci_slot->kobj, 340 &hotplug_slot_attr_presence.attr); 341 if (retval) 342 goto exit_adapter; 343 } 344 345 if (has_test_file(pci_slot)) { 346 retval = sysfs_create_file(&pci_slot->kobj, 347 &hotplug_slot_attr_test.attr); 348 if (retval) 349 goto exit_test; 350 } 351 352 goto exit; 353 354 exit_test: 355 if (has_adapter_file(pci_slot)) 356 sysfs_remove_file(&pci_slot->kobj, 357 &hotplug_slot_attr_presence.attr); 358 exit_adapter: 359 if (has_latch_file(pci_slot)) 360 sysfs_remove_file(&pci_slot->kobj, &hotplug_slot_attr_latch.attr); 361 exit_latch: 362 if (has_attention_file(pci_slot)) 363 sysfs_remove_file(&pci_slot->kobj, 364 &hotplug_slot_attr_attention.attr); 365 exit_attention: 366 if (has_power_file(pci_slot)) 367 sysfs_remove_file(&pci_slot->kobj, &hotplug_slot_attr_power.attr); 368 exit_power: 369 pci_hp_remove_module_link(pci_slot); 370 exit: 371 return retval; 372 } 373 374 static void fs_remove_slot(struct pci_slot *pci_slot) 375 { 376 if (has_power_file(pci_slot)) 377 sysfs_remove_file(&pci_slot->kobj, &hotplug_slot_attr_power.attr); 378 379 if (has_attention_file(pci_slot)) 380 sysfs_remove_file(&pci_slot->kobj, 381 &hotplug_slot_attr_attention.attr); 382 383 if (has_latch_file(pci_slot)) 384 sysfs_remove_file(&pci_slot->kobj, &hotplug_slot_attr_latch.attr); 385 386 if (has_adapter_file(pci_slot)) 387 sysfs_remove_file(&pci_slot->kobj, 388 &hotplug_slot_attr_presence.attr); 389 390 if (has_test_file(pci_slot)) 391 sysfs_remove_file(&pci_slot->kobj, &hotplug_slot_attr_test.attr); 392 393 pci_hp_remove_module_link(pci_slot); 394 } 395 396 static struct hotplug_slot *get_slot_from_name(const char *name) 397 { 398 struct hotplug_slot *slot; 399 400 list_for_each_entry(slot, &pci_hotplug_slot_list, slot_list) { 401 if (strcmp(hotplug_slot_name(slot), name) == 0) 402 return slot; 403 } 404 return NULL; 405 } 406 407 /** 408 * __pci_hp_register - register a hotplug_slot with the PCI hotplug subsystem 409 * @bus: bus this slot is on 410 * @slot: pointer to the &struct hotplug_slot to register 411 * @devnr: device number 412 * @name: name registered with kobject core 413 * @owner: caller module owner 414 * @mod_name: caller module name 415 * 416 * Registers a hotplug slot with the pci hotplug subsystem, which will allow 417 * userspace interaction to the slot. 418 * 419 * Returns 0 if successful, anything else for an error. 420 */ 421 int __pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, 422 int devnr, const char *name, 423 struct module *owner, const char *mod_name) 424 { 425 int result; 426 struct pci_slot *pci_slot; 427 428 if (slot == NULL) 429 return -ENODEV; 430 if ((slot->info == NULL) || (slot->ops == NULL)) 431 return -EINVAL; 432 if (slot->release == NULL) { 433 dbg("Why are you trying to register a hotplug slot without a proper release function?\n"); 434 return -EINVAL; 435 } 436 437 slot->ops->owner = owner; 438 slot->ops->mod_name = mod_name; 439 440 mutex_lock(&pci_hp_mutex); 441 /* 442 * No problems if we call this interface from both ACPI_PCI_SLOT 443 * driver and call it here again. If we've already created the 444 * pci_slot, the interface will simply bump the refcount. 445 */ 446 pci_slot = pci_create_slot(bus, devnr, name, slot); 447 if (IS_ERR(pci_slot)) { 448 result = PTR_ERR(pci_slot); 449 goto out; 450 } 451 452 slot->pci_slot = pci_slot; 453 pci_slot->hotplug = slot; 454 455 list_add(&slot->slot_list, &pci_hotplug_slot_list); 456 457 result = fs_add_slot(pci_slot); 458 kobject_uevent(&pci_slot->kobj, KOBJ_ADD); 459 dbg("Added slot %s to the list\n", name); 460 out: 461 mutex_unlock(&pci_hp_mutex); 462 return result; 463 } 464 EXPORT_SYMBOL_GPL(__pci_hp_register); 465 466 /** 467 * pci_hp_deregister - deregister a hotplug_slot with the PCI hotplug subsystem 468 * @slot: pointer to the &struct hotplug_slot to deregister 469 * 470 * The @slot must have been registered with the pci hotplug subsystem 471 * previously with a call to pci_hp_register(). 472 * 473 * Returns 0 if successful, anything else for an error. 474 */ 475 int pci_hp_deregister(struct hotplug_slot *slot) 476 { 477 struct hotplug_slot *temp; 478 struct pci_slot *pci_slot; 479 480 if (!slot) 481 return -ENODEV; 482 483 mutex_lock(&pci_hp_mutex); 484 temp = get_slot_from_name(hotplug_slot_name(slot)); 485 if (temp != slot) { 486 mutex_unlock(&pci_hp_mutex); 487 return -ENODEV; 488 } 489 490 list_del(&slot->slot_list); 491 492 pci_slot = slot->pci_slot; 493 fs_remove_slot(pci_slot); 494 dbg("Removed slot %s from the list\n", hotplug_slot_name(slot)); 495 496 slot->release(slot); 497 pci_slot->hotplug = NULL; 498 pci_destroy_slot(pci_slot); 499 mutex_unlock(&pci_hp_mutex); 500 501 return 0; 502 } 503 EXPORT_SYMBOL_GPL(pci_hp_deregister); 504 505 /** 506 * pci_hp_change_slot_info - changes the slot's information structure in the core 507 * @slot: pointer to the slot whose info has changed 508 * @info: pointer to the info copy into the slot's info structure 509 * 510 * @slot must have been registered with the pci 511 * hotplug subsystem previously with a call to pci_hp_register(). 512 * 513 * Returns 0 if successful, anything else for an error. 514 */ 515 int pci_hp_change_slot_info(struct hotplug_slot *slot, 516 struct hotplug_slot_info *info) 517 { 518 if (!slot || !info) 519 return -ENODEV; 520 521 memcpy(slot->info, info, sizeof(struct hotplug_slot_info)); 522 523 return 0; 524 } 525 EXPORT_SYMBOL_GPL(pci_hp_change_slot_info); 526 527 static int __init pci_hotplug_init(void) 528 { 529 int result; 530 531 result = cpci_hotplug_init(debug); 532 if (result) { 533 err("cpci_hotplug_init with error %d\n", result); 534 return result; 535 } 536 537 info(DRIVER_DESC " version: " DRIVER_VERSION "\n"); 538 return result; 539 } 540 device_initcall(pci_hotplug_init); 541 542 /* 543 * not really modular, but the easiest way to keep compat with existing 544 * bootargs behaviour is to continue using module_param here. 545 */ 546 module_param(debug, bool, 0644); 547 MODULE_PARM_DESC(debug, "Debugging mode enabled or not"); 548