pci-driver.c revision 50b0075520a0acba9cabab5203bbce918b966d9a
1/* 2 * drivers/pci/pci-driver.c 3 * 4 */ 5 6#include <linux/pci.h> 7#include <linux/module.h> 8#include <linux/init.h> 9#include <linux/device.h> 10#include <linux/mempolicy.h> 11#include <linux/string.h> 12#include <linux/slab.h> 13#include <linux/sched.h> 14#include "pci.h" 15 16/* 17 * Registration of PCI drivers and handling of hot-pluggable devices. 18 */ 19 20/* multithreaded probe logic */ 21static int pci_multithread_probe = 22#ifdef CONFIG_PCI_MULTITHREAD_PROBE 23 1; 24#else 25 0; 26#endif 27__module_param_call("", pci_multithread_probe, param_set_bool, param_get_bool, &pci_multithread_probe, 0644); 28 29 30/* 31 * Dynamic device IDs are disabled for !CONFIG_HOTPLUG 32 */ 33 34struct pci_dynid { 35 struct list_head node; 36 struct pci_device_id id; 37}; 38 39#ifdef CONFIG_HOTPLUG 40 41/** 42 * store_new_id - add a new PCI device ID to this driver and re-probe devices 43 * @driver: target device driver 44 * @buf: buffer for scanning device ID data 45 * @count: input size 46 * 47 * Adds a new dynamic pci device ID to this driver, 48 * and causes the driver to probe for all devices again. 49 */ 50static ssize_t 51store_new_id(struct device_driver *driver, const char *buf, size_t count) 52{ 53 struct pci_dynid *dynid; 54 struct pci_driver *pdrv = to_pci_driver(driver); 55 __u32 vendor=PCI_ANY_ID, device=PCI_ANY_ID, subvendor=PCI_ANY_ID, 56 subdevice=PCI_ANY_ID, class=0, class_mask=0; 57 unsigned long driver_data=0; 58 int fields=0; 59 int retval = 0; 60 61 fields = sscanf(buf, "%x %x %x %x %x %x %lux", 62 &vendor, &device, &subvendor, &subdevice, 63 &class, &class_mask, &driver_data); 64 if (fields < 0) 65 return -EINVAL; 66 67 dynid = kzalloc(sizeof(*dynid), GFP_KERNEL); 68 if (!dynid) 69 return -ENOMEM; 70 71 INIT_LIST_HEAD(&dynid->node); 72 dynid->id.vendor = vendor; 73 dynid->id.device = device; 74 dynid->id.subvendor = subvendor; 75 dynid->id.subdevice = subdevice; 76 dynid->id.class = class; 77 dynid->id.class_mask = class_mask; 78 dynid->id.driver_data = pdrv->dynids.use_driver_data ? 79 driver_data : 0UL; 80 81 spin_lock(&pdrv->dynids.lock); 82 list_add_tail(&pdrv->dynids.list, &dynid->node); 83 spin_unlock(&pdrv->dynids.lock); 84 85 if (get_driver(&pdrv->driver)) { 86 retval = driver_attach(&pdrv->driver); 87 put_driver(&pdrv->driver); 88 } 89 90 if (retval) 91 return retval; 92 return count; 93} 94static DRIVER_ATTR(new_id, S_IWUSR, NULL, store_new_id); 95 96static void 97pci_free_dynids(struct pci_driver *drv) 98{ 99 struct pci_dynid *dynid, *n; 100 101 spin_lock(&drv->dynids.lock); 102 list_for_each_entry_safe(dynid, n, &drv->dynids.list, node) { 103 list_del(&dynid->node); 104 kfree(dynid); 105 } 106 spin_unlock(&drv->dynids.lock); 107} 108 109static int 110pci_create_newid_file(struct pci_driver *drv) 111{ 112 int error = 0; 113 if (drv->probe != NULL) 114 error = sysfs_create_file(&drv->driver.kobj, 115 &driver_attr_new_id.attr); 116 return error; 117} 118 119#else /* !CONFIG_HOTPLUG */ 120static inline void pci_free_dynids(struct pci_driver *drv) {} 121static inline int pci_create_newid_file(struct pci_driver *drv) 122{ 123 return 0; 124} 125#endif 126 127/** 128 * pci_match_id - See if a pci device matches a given pci_id table 129 * @ids: array of PCI device id structures to search in 130 * @dev: the PCI device structure to match against. 131 * 132 * Used by a driver to check whether a PCI device present in the 133 * system is in its list of supported devices. Returns the matching 134 * pci_device_id structure or %NULL if there is no match. 135 * 136 * Depreciated, don't use this as it will not catch any dynamic ids 137 * that a driver might want to check for. 138 */ 139const struct pci_device_id *pci_match_id(const struct pci_device_id *ids, 140 struct pci_dev *dev) 141{ 142 if (ids) { 143 while (ids->vendor || ids->subvendor || ids->class_mask) { 144 if (pci_match_one_device(ids, dev)) 145 return ids; 146 ids++; 147 } 148 } 149 return NULL; 150} 151 152/** 153 * pci_match_device - Tell if a PCI device structure has a matching 154 * PCI device id structure 155 * @drv: the PCI driver to match against 156 * @dev: the PCI device structure to match against 157 * 158 * Used by a driver to check whether a PCI device present in the 159 * system is in its list of supported devices. Returns the matching 160 * pci_device_id structure or %NULL if there is no match. 161 */ 162const struct pci_device_id *pci_match_device(struct pci_driver *drv, 163 struct pci_dev *dev) 164{ 165 const struct pci_device_id *id; 166 struct pci_dynid *dynid; 167 168 id = pci_match_id(drv->id_table, dev); 169 if (id) 170 return id; 171 172 /* static ids didn't match, lets look at the dynamic ones */ 173 spin_lock(&drv->dynids.lock); 174 list_for_each_entry(dynid, &drv->dynids.list, node) { 175 if (pci_match_one_device(&dynid->id, dev)) { 176 spin_unlock(&drv->dynids.lock); 177 return &dynid->id; 178 } 179 } 180 spin_unlock(&drv->dynids.lock); 181 return NULL; 182} 183 184static int pci_call_probe(struct pci_driver *drv, struct pci_dev *dev, 185 const struct pci_device_id *id) 186{ 187 int error; 188#ifdef CONFIG_NUMA 189 /* Execute driver initialization on node where the 190 device's bus is attached to. This way the driver likely 191 allocates its local memory on the right node without 192 any need to change it. */ 193 struct mempolicy *oldpol; 194 cpumask_t oldmask = current->cpus_allowed; 195 int node = pcibus_to_node(dev->bus); 196 if (node >= 0 && node_online(node)) 197 set_cpus_allowed(current, node_to_cpumask(node)); 198 /* And set default memory allocation policy */ 199 oldpol = current->mempolicy; 200 current->mempolicy = &default_policy; 201 mpol_get(current->mempolicy); 202#endif 203 error = drv->probe(dev, id); 204#ifdef CONFIG_NUMA 205 set_cpus_allowed(current, oldmask); 206 mpol_free(current->mempolicy); 207 current->mempolicy = oldpol; 208#endif 209 return error; 210} 211 212/** 213 * __pci_device_probe() 214 * @drv: driver to call to check if it wants the PCI device 215 * @pci_dev: PCI device being probed 216 * 217 * returns 0 on success, else error. 218 * side-effect: pci_dev->driver is set to drv when drv claims pci_dev. 219 */ 220static int 221__pci_device_probe(struct pci_driver *drv, struct pci_dev *pci_dev) 222{ 223 const struct pci_device_id *id; 224 int error = 0; 225 226 if (!pci_dev->driver && drv->probe) { 227 error = -ENODEV; 228 229 id = pci_match_device(drv, pci_dev); 230 if (id) 231 error = pci_call_probe(drv, pci_dev, id); 232 if (error >= 0) { 233 pci_dev->driver = drv; 234 error = 0; 235 } 236 } 237 return error; 238} 239 240static int pci_device_probe(struct device * dev) 241{ 242 int error = 0; 243 struct pci_driver *drv; 244 struct pci_dev *pci_dev; 245 246 drv = to_pci_driver(dev->driver); 247 pci_dev = to_pci_dev(dev); 248 pci_dev_get(pci_dev); 249 error = __pci_device_probe(drv, pci_dev); 250 if (error) 251 pci_dev_put(pci_dev); 252 253 return error; 254} 255 256static int pci_device_remove(struct device * dev) 257{ 258 struct pci_dev * pci_dev = to_pci_dev(dev); 259 struct pci_driver * drv = pci_dev->driver; 260 261 if (drv) { 262 if (drv->remove) 263 drv->remove(pci_dev); 264 pci_dev->driver = NULL; 265 } 266 267 /* 268 * We would love to complain here if pci_dev->is_enabled is set, that 269 * the driver should have called pci_disable_device(), but the 270 * unfortunate fact is there are too many odd BIOS and bridge setups 271 * that don't like drivers doing that all of the time. 272 * Oh well, we can dream of sane hardware when we sleep, no matter how 273 * horrible the crap we have to deal with is when we are awake... 274 */ 275 276 pci_dev_put(pci_dev); 277 return 0; 278} 279 280static int pci_device_suspend(struct device * dev, pm_message_t state) 281{ 282 struct pci_dev * pci_dev = to_pci_dev(dev); 283 struct pci_driver * drv = pci_dev->driver; 284 int i = 0; 285 286 if (drv && drv->suspend) { 287 i = drv->suspend(pci_dev, state); 288 suspend_report_result(drv->suspend, i); 289 } else { 290 pci_save_state(pci_dev); 291 } 292 return i; 293} 294 295static int pci_device_suspend_late(struct device * dev, pm_message_t state) 296{ 297 struct pci_dev * pci_dev = to_pci_dev(dev); 298 struct pci_driver * drv = pci_dev->driver; 299 int i = 0; 300 301 if (drv && drv->suspend_late) { 302 i = drv->suspend_late(pci_dev, state); 303 suspend_report_result(drv->suspend_late, i); 304 } 305 return i; 306} 307 308/* 309 * Default resume method for devices that have no driver provided resume, 310 * or not even a driver at all. 311 */ 312static int pci_default_resume(struct pci_dev *pci_dev) 313{ 314 int retval = 0; 315 316 /* restore the PCI config space */ 317 pci_restore_state(pci_dev); 318 /* if the device was enabled before suspend, reenable */ 319 if (pci_dev->is_enabled) 320 retval = pci_enable_device(pci_dev); 321 /* if the device was busmaster before the suspend, make it busmaster again */ 322 if (pci_dev->is_busmaster) 323 pci_set_master(pci_dev); 324 325 return retval; 326} 327 328static int pci_device_resume(struct device * dev) 329{ 330 int error; 331 struct pci_dev * pci_dev = to_pci_dev(dev); 332 struct pci_driver * drv = pci_dev->driver; 333 334 if (drv && drv->resume) 335 error = drv->resume(pci_dev); 336 else 337 error = pci_default_resume(pci_dev); 338 return error; 339} 340 341static int pci_device_resume_early(struct device * dev) 342{ 343 int error = 0; 344 struct pci_dev * pci_dev = to_pci_dev(dev); 345 struct pci_driver * drv = pci_dev->driver; 346 347 if (drv && drv->resume_early) 348 error = drv->resume_early(pci_dev); 349 return error; 350} 351 352static void pci_device_shutdown(struct device *dev) 353{ 354 struct pci_dev *pci_dev = to_pci_dev(dev); 355 struct pci_driver *drv = pci_dev->driver; 356 357 if (drv && drv->shutdown) 358 drv->shutdown(pci_dev); 359} 360 361#define kobj_to_pci_driver(obj) container_of(obj, struct device_driver, kobj) 362#define attr_to_driver_attribute(obj) container_of(obj, struct driver_attribute, attr) 363 364static ssize_t 365pci_driver_attr_show(struct kobject * kobj, struct attribute *attr, char *buf) 366{ 367 struct device_driver *driver = kobj_to_pci_driver(kobj); 368 struct driver_attribute *dattr = attr_to_driver_attribute(attr); 369 ssize_t ret; 370 371 if (!get_driver(driver)) 372 return -ENODEV; 373 374 ret = dattr->show ? dattr->show(driver, buf) : -EIO; 375 376 put_driver(driver); 377 return ret; 378} 379 380static ssize_t 381pci_driver_attr_store(struct kobject * kobj, struct attribute *attr, 382 const char *buf, size_t count) 383{ 384 struct device_driver *driver = kobj_to_pci_driver(kobj); 385 struct driver_attribute *dattr = attr_to_driver_attribute(attr); 386 ssize_t ret; 387 388 if (!get_driver(driver)) 389 return -ENODEV; 390 391 ret = dattr->store ? dattr->store(driver, buf, count) : -EIO; 392 393 put_driver(driver); 394 return ret; 395} 396 397static struct sysfs_ops pci_driver_sysfs_ops = { 398 .show = pci_driver_attr_show, 399 .store = pci_driver_attr_store, 400}; 401static struct kobj_type pci_driver_kobj_type = { 402 .sysfs_ops = &pci_driver_sysfs_ops, 403}; 404 405/** 406 * __pci_register_driver - register a new pci driver 407 * @drv: the driver structure to register 408 * @owner: owner module of drv 409 * 410 * Adds the driver structure to the list of registered drivers. 411 * Returns a negative value on error, otherwise 0. 412 * If no error occurred, the driver remains registered even if 413 * no device was claimed during registration. 414 */ 415int __pci_register_driver(struct pci_driver *drv, struct module *owner) 416{ 417 int error; 418 419 /* initialize common driver fields */ 420 drv->driver.name = drv->name; 421 drv->driver.bus = &pci_bus_type; 422 drv->driver.owner = owner; 423 drv->driver.kobj.ktype = &pci_driver_kobj_type; 424 425 if (pci_multithread_probe) 426 drv->driver.multithread_probe = pci_multithread_probe; 427 else 428 drv->driver.multithread_probe = drv->multithread_probe; 429 430 spin_lock_init(&drv->dynids.lock); 431 INIT_LIST_HEAD(&drv->dynids.list); 432 433 /* register with core */ 434 error = driver_register(&drv->driver); 435 436 if (!error) 437 error = pci_create_newid_file(drv); 438 439 return error; 440} 441 442/** 443 * pci_unregister_driver - unregister a pci driver 444 * @drv: the driver structure to unregister 445 * 446 * Deletes the driver structure from the list of registered PCI drivers, 447 * gives it a chance to clean up by calling its remove() function for 448 * each device it was responsible for, and marks those devices as 449 * driverless. 450 */ 451 452void 453pci_unregister_driver(struct pci_driver *drv) 454{ 455 driver_unregister(&drv->driver); 456 pci_free_dynids(drv); 457} 458 459static struct pci_driver pci_compat_driver = { 460 .name = "compat" 461}; 462 463/** 464 * pci_dev_driver - get the pci_driver of a device 465 * @dev: the device to query 466 * 467 * Returns the appropriate pci_driver structure or %NULL if there is no 468 * registered driver for the device. 469 */ 470struct pci_driver * 471pci_dev_driver(const struct pci_dev *dev) 472{ 473 if (dev->driver) 474 return dev->driver; 475 else { 476 int i; 477 for(i=0; i<=PCI_ROM_RESOURCE; i++) 478 if (dev->resource[i].flags & IORESOURCE_BUSY) 479 return &pci_compat_driver; 480 } 481 return NULL; 482} 483 484/** 485 * pci_bus_match - Tell if a PCI device structure has a matching PCI device id structure 486 * @dev: the PCI device structure to match against 487 * @drv: the device driver to search for matching PCI device id structures 488 * 489 * Used by a driver to check whether a PCI device present in the 490 * system is in its list of supported devices. Returns the matching 491 * pci_device_id structure or %NULL if there is no match. 492 */ 493static int pci_bus_match(struct device *dev, struct device_driver *drv) 494{ 495 struct pci_dev *pci_dev = to_pci_dev(dev); 496 struct pci_driver *pci_drv = to_pci_driver(drv); 497 const struct pci_device_id *found_id; 498 499 found_id = pci_match_device(pci_drv, pci_dev); 500 if (found_id) 501 return 1; 502 503 return 0; 504} 505 506/** 507 * pci_dev_get - increments the reference count of the pci device structure 508 * @dev: the device being referenced 509 * 510 * Each live reference to a device should be refcounted. 511 * 512 * Drivers for PCI devices should normally record such references in 513 * their probe() methods, when they bind to a device, and release 514 * them by calling pci_dev_put(), in their disconnect() methods. 515 * 516 * A pointer to the device with the incremented reference counter is returned. 517 */ 518struct pci_dev *pci_dev_get(struct pci_dev *dev) 519{ 520 if (dev) 521 get_device(&dev->dev); 522 return dev; 523} 524 525/** 526 * pci_dev_put - release a use of the pci device structure 527 * @dev: device that's been disconnected 528 * 529 * Must be called when a user of a device is finished with it. When the last 530 * user of the device calls this function, the memory of the device is freed. 531 */ 532void pci_dev_put(struct pci_dev *dev) 533{ 534 if (dev) 535 put_device(&dev->dev); 536} 537 538#ifndef CONFIG_HOTPLUG 539int pci_uevent(struct device *dev, char **envp, int num_envp, 540 char *buffer, int buffer_size) 541{ 542 return -ENODEV; 543} 544#endif 545 546struct bus_type pci_bus_type = { 547 .name = "pci", 548 .match = pci_bus_match, 549 .uevent = pci_uevent, 550 .probe = pci_device_probe, 551 .remove = pci_device_remove, 552 .suspend = pci_device_suspend, 553 .suspend_late = pci_device_suspend_late, 554 .resume_early = pci_device_resume_early, 555 .resume = pci_device_resume, 556 .shutdown = pci_device_shutdown, 557 .dev_attrs = pci_dev_attrs, 558}; 559 560static int __init pci_driver_init(void) 561{ 562 return bus_register(&pci_bus_type); 563} 564 565postcore_initcall(pci_driver_init); 566 567EXPORT_SYMBOL(pci_match_id); 568EXPORT_SYMBOL(pci_match_device); 569EXPORT_SYMBOL(__pci_register_driver); 570EXPORT_SYMBOL(pci_unregister_driver); 571EXPORT_SYMBOL(pci_dev_driver); 572EXPORT_SYMBOL(pci_bus_type); 573EXPORT_SYMBOL(pci_dev_get); 574EXPORT_SYMBOL(pci_dev_put); 575