pci-driver.c revision 21c7f30b1d3f8a3de3128478daca3ce203fc8733
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 PCI device id structure 154 * @drv: the PCI driver to match against 155 * @dev: the PCI device structure to match against 156 * 157 * Used by a driver to check whether a PCI device present in the 158 * system is in its list of supported devices. Returns the matching 159 * pci_device_id structure or %NULL if there is no match. 160 */ 161const struct pci_device_id *pci_match_device(struct pci_driver *drv, 162 struct pci_dev *dev) 163{ 164 struct pci_dynid *dynid; 165 166 /* Look at the dynamic ids first, before the static ones */ 167 spin_lock(&drv->dynids.lock); 168 list_for_each_entry(dynid, &drv->dynids.list, node) { 169 if (pci_match_one_device(&dynid->id, dev)) { 170 spin_unlock(&drv->dynids.lock); 171 return &dynid->id; 172 } 173 } 174 spin_unlock(&drv->dynids.lock); 175 176 return pci_match_id(drv->id_table, dev); 177} 178 179static int pci_call_probe(struct pci_driver *drv, struct pci_dev *dev, 180 const struct pci_device_id *id) 181{ 182 int error; 183#ifdef CONFIG_NUMA 184 /* Execute driver initialization on node where the 185 device's bus is attached to. This way the driver likely 186 allocates its local memory on the right node without 187 any need to change it. */ 188 struct mempolicy *oldpol; 189 cpumask_t oldmask = current->cpus_allowed; 190 int node = pcibus_to_node(dev->bus); 191 if (node >= 0 && node_online(node)) 192 set_cpus_allowed(current, node_to_cpumask(node)); 193 /* And set default memory allocation policy */ 194 oldpol = current->mempolicy; 195 current->mempolicy = &default_policy; 196 mpol_get(current->mempolicy); 197#endif 198 error = drv->probe(dev, id); 199#ifdef CONFIG_NUMA 200 set_cpus_allowed(current, oldmask); 201 mpol_free(current->mempolicy); 202 current->mempolicy = oldpol; 203#endif 204 return error; 205} 206 207/** 208 * __pci_device_probe() 209 * @drv: driver to call to check if it wants the PCI device 210 * @pci_dev: PCI device being probed 211 * 212 * returns 0 on success, else error. 213 * side-effect: pci_dev->driver is set to drv when drv claims pci_dev. 214 */ 215static int 216__pci_device_probe(struct pci_driver *drv, struct pci_dev *pci_dev) 217{ 218 const struct pci_device_id *id; 219 int error = 0; 220 221 if (!pci_dev->driver && drv->probe) { 222 error = -ENODEV; 223 224 id = pci_match_device(drv, pci_dev); 225 if (id) 226 error = pci_call_probe(drv, pci_dev, id); 227 if (error >= 0) { 228 pci_dev->driver = drv; 229 error = 0; 230 } 231 } 232 return error; 233} 234 235static int pci_device_probe(struct device * dev) 236{ 237 int error = 0; 238 struct pci_driver *drv; 239 struct pci_dev *pci_dev; 240 241 drv = to_pci_driver(dev->driver); 242 pci_dev = to_pci_dev(dev); 243 pci_dev_get(pci_dev); 244 error = __pci_device_probe(drv, pci_dev); 245 if (error) 246 pci_dev_put(pci_dev); 247 248 return error; 249} 250 251static int pci_device_remove(struct device * dev) 252{ 253 struct pci_dev * pci_dev = to_pci_dev(dev); 254 struct pci_driver * drv = pci_dev->driver; 255 256 if (drv) { 257 if (drv->remove) 258 drv->remove(pci_dev); 259 pci_dev->driver = NULL; 260 } 261 262 /* 263 * If the device is still on, set the power state as "unknown", 264 * since it might change by the next time we load the driver. 265 */ 266 if (pci_dev->current_state == PCI_D0) 267 pci_dev->current_state = PCI_UNKNOWN; 268 269 /* 270 * We would love to complain here if pci_dev->is_enabled is set, that 271 * the driver should have called pci_disable_device(), but the 272 * unfortunate fact is there are too many odd BIOS and bridge setups 273 * that don't like drivers doing that all of the time. 274 * Oh well, we can dream of sane hardware when we sleep, no matter how 275 * horrible the crap we have to deal with is when we are awake... 276 */ 277 278 pci_dev_put(pci_dev); 279 return 0; 280} 281 282static int pci_device_suspend(struct device * dev, pm_message_t state) 283{ 284 struct pci_dev * pci_dev = to_pci_dev(dev); 285 struct pci_driver * drv = pci_dev->driver; 286 int i = 0; 287 288 if (drv && drv->suspend) { 289 i = drv->suspend(pci_dev, state); 290 suspend_report_result(drv->suspend, i); 291 } else { 292 pci_save_state(pci_dev); 293 /* 294 * mark its power state as "unknown", since we don't know if 295 * e.g. the BIOS will change its device state when we suspend. 296 */ 297 if (pci_dev->current_state == PCI_D0) 298 pci_dev->current_state = PCI_UNKNOWN; 299 } 300 return i; 301} 302 303static int pci_device_suspend_late(struct device * dev, pm_message_t state) 304{ 305 struct pci_dev * pci_dev = to_pci_dev(dev); 306 struct pci_driver * drv = pci_dev->driver; 307 int i = 0; 308 309 if (drv && drv->suspend_late) { 310 i = drv->suspend_late(pci_dev, state); 311 suspend_report_result(drv->suspend_late, i); 312 } 313 return i; 314} 315 316/* 317 * Default resume method for devices that have no driver provided resume, 318 * or not even a driver at all. 319 */ 320static int pci_default_resume(struct pci_dev *pci_dev) 321{ 322 int retval = 0; 323 324 /* restore the PCI config space */ 325 pci_restore_state(pci_dev); 326 /* if the device was enabled before suspend, reenable */ 327 retval = __pci_reenable_device(pci_dev); 328 /* if the device was busmaster before the suspend, make it busmaster again */ 329 if (pci_dev->is_busmaster) 330 pci_set_master(pci_dev); 331 332 return retval; 333} 334 335static int pci_device_resume(struct device * dev) 336{ 337 int error; 338 struct pci_dev * pci_dev = to_pci_dev(dev); 339 struct pci_driver * drv = pci_dev->driver; 340 341 if (drv && drv->resume) 342 error = drv->resume(pci_dev); 343 else 344 error = pci_default_resume(pci_dev); 345 return error; 346} 347 348static int pci_device_resume_early(struct device * dev) 349{ 350 int error = 0; 351 struct pci_dev * pci_dev = to_pci_dev(dev); 352 struct pci_driver * drv = pci_dev->driver; 353 354 pci_fixup_device(pci_fixup_resume, pci_dev); 355 356 if (drv && drv->resume_early) 357 error = drv->resume_early(pci_dev); 358 return error; 359} 360 361static void pci_device_shutdown(struct device *dev) 362{ 363 struct pci_dev *pci_dev = to_pci_dev(dev); 364 struct pci_driver *drv = pci_dev->driver; 365 366 if (drv && drv->shutdown) 367 drv->shutdown(pci_dev); 368} 369 370#define kobj_to_pci_driver(obj) container_of(obj, struct device_driver, kobj) 371#define attr_to_driver_attribute(obj) container_of(obj, struct driver_attribute, attr) 372 373static ssize_t 374pci_driver_attr_show(struct kobject * kobj, struct attribute *attr, char *buf) 375{ 376 struct device_driver *driver = kobj_to_pci_driver(kobj); 377 struct driver_attribute *dattr = attr_to_driver_attribute(attr); 378 ssize_t ret; 379 380 if (!get_driver(driver)) 381 return -ENODEV; 382 383 ret = dattr->show ? dattr->show(driver, buf) : -EIO; 384 385 put_driver(driver); 386 return ret; 387} 388 389static ssize_t 390pci_driver_attr_store(struct kobject * kobj, struct attribute *attr, 391 const char *buf, size_t count) 392{ 393 struct device_driver *driver = kobj_to_pci_driver(kobj); 394 struct driver_attribute *dattr = attr_to_driver_attribute(attr); 395 ssize_t ret; 396 397 if (!get_driver(driver)) 398 return -ENODEV; 399 400 ret = dattr->store ? dattr->store(driver, buf, count) : -EIO; 401 402 put_driver(driver); 403 return ret; 404} 405 406static struct sysfs_ops pci_driver_sysfs_ops = { 407 .show = pci_driver_attr_show, 408 .store = pci_driver_attr_store, 409}; 410static struct kobj_type pci_driver_kobj_type = { 411 .sysfs_ops = &pci_driver_sysfs_ops, 412}; 413 414/** 415 * __pci_register_driver - register a new pci driver 416 * @drv: the driver structure to register 417 * @owner: owner module of drv 418 * @mod_name: module name string 419 * 420 * Adds the driver structure to the list of registered drivers. 421 * Returns a negative value on error, otherwise 0. 422 * If no error occurred, the driver remains registered even if 423 * no device was claimed during registration. 424 */ 425int __pci_register_driver(struct pci_driver *drv, struct module *owner, 426 const char *mod_name) 427{ 428 int error; 429 430 /* initialize common driver fields */ 431 drv->driver.name = drv->name; 432 drv->driver.bus = &pci_bus_type; 433 drv->driver.owner = owner; 434 drv->driver.mod_name = mod_name; 435 drv->driver.kobj.ktype = &pci_driver_kobj_type; 436 437 spin_lock_init(&drv->dynids.lock); 438 INIT_LIST_HEAD(&drv->dynids.list); 439 440 /* register with core */ 441 error = driver_register(&drv->driver); 442 if (error) 443 return error; 444 445 error = pci_create_newid_file(drv); 446 if (error) 447 driver_unregister(&drv->driver); 448 449 return error; 450} 451 452/** 453 * pci_unregister_driver - unregister a pci driver 454 * @drv: the driver structure to unregister 455 * 456 * Deletes the driver structure from the list of registered PCI drivers, 457 * gives it a chance to clean up by calling its remove() function for 458 * each device it was responsible for, and marks those devices as 459 * driverless. 460 */ 461 462void 463pci_unregister_driver(struct pci_driver *drv) 464{ 465 driver_unregister(&drv->driver); 466 pci_free_dynids(drv); 467} 468 469static struct pci_driver pci_compat_driver = { 470 .name = "compat" 471}; 472 473/** 474 * pci_dev_driver - get the pci_driver of a device 475 * @dev: the device to query 476 * 477 * Returns the appropriate pci_driver structure or %NULL if there is no 478 * registered driver for the device. 479 */ 480struct pci_driver * 481pci_dev_driver(const struct pci_dev *dev) 482{ 483 if (dev->driver) 484 return dev->driver; 485 else { 486 int i; 487 for(i=0; i<=PCI_ROM_RESOURCE; i++) 488 if (dev->resource[i].flags & IORESOURCE_BUSY) 489 return &pci_compat_driver; 490 } 491 return NULL; 492} 493 494/** 495 * pci_bus_match - Tell if a PCI device structure has a matching PCI device id structure 496 * @dev: the PCI device structure to match against 497 * @drv: the device driver to search for matching PCI device id structures 498 * 499 * Used by a driver to check whether a PCI device present in the 500 * system is in its list of supported devices. Returns the matching 501 * pci_device_id structure or %NULL if there is no match. 502 */ 503static int pci_bus_match(struct device *dev, struct device_driver *drv) 504{ 505 struct pci_dev *pci_dev = to_pci_dev(dev); 506 struct pci_driver *pci_drv = to_pci_driver(drv); 507 const struct pci_device_id *found_id; 508 509 found_id = pci_match_device(pci_drv, pci_dev); 510 if (found_id) 511 return 1; 512 513 return 0; 514} 515 516/** 517 * pci_dev_get - increments the reference count of the pci device structure 518 * @dev: the device being referenced 519 * 520 * Each live reference to a device should be refcounted. 521 * 522 * Drivers for PCI devices should normally record such references in 523 * their probe() methods, when they bind to a device, and release 524 * them by calling pci_dev_put(), in their disconnect() methods. 525 * 526 * A pointer to the device with the incremented reference counter is returned. 527 */ 528struct pci_dev *pci_dev_get(struct pci_dev *dev) 529{ 530 if (dev) 531 get_device(&dev->dev); 532 return dev; 533} 534 535/** 536 * pci_dev_put - release a use of the pci device structure 537 * @dev: device that's been disconnected 538 * 539 * Must be called when a user of a device is finished with it. When the last 540 * user of the device calls this function, the memory of the device is freed. 541 */ 542void pci_dev_put(struct pci_dev *dev) 543{ 544 if (dev) 545 put_device(&dev->dev); 546} 547 548#ifndef CONFIG_HOTPLUG 549int pci_uevent(struct device *dev, char **envp, int num_envp, 550 char *buffer, int buffer_size) 551{ 552 return -ENODEV; 553} 554#endif 555 556struct bus_type pci_bus_type = { 557 .name = "pci", 558 .match = pci_bus_match, 559 .uevent = pci_uevent, 560 .probe = pci_device_probe, 561 .remove = pci_device_remove, 562 .suspend = pci_device_suspend, 563 .suspend_late = pci_device_suspend_late, 564 .resume_early = pci_device_resume_early, 565 .resume = pci_device_resume, 566 .shutdown = pci_device_shutdown, 567 .dev_attrs = pci_dev_attrs, 568}; 569 570static int __init pci_driver_init(void) 571{ 572 pci_bus_type.multithread_probe = pci_multithread_probe; 573 return bus_register(&pci_bus_type); 574} 575 576postcore_initcall(pci_driver_init); 577 578EXPORT_SYMBOL(pci_match_id); 579EXPORT_SYMBOL(pci_match_device); 580EXPORT_SYMBOL(__pci_register_driver); 581EXPORT_SYMBOL(pci_unregister_driver); 582EXPORT_SYMBOL(pci_dev_driver); 583EXPORT_SYMBOL(pci_bus_type); 584EXPORT_SYMBOL(pci_dev_get); 585EXPORT_SYMBOL(pci_dev_put); 586