drivers/pci/pci-driver.c

   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 */
  21 static 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
  34 struct 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  */
  50 static ssize_t
  51 store_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 }
  94 static DRIVER_ATTR(new_id, S_IWUSR, NULL, store_new_id);
  95
  96 static void
  97 pci_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
 109 static int
 110 pci_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 */
 120 static inline void pci_free_dynids(struct pci_driver *drv) {}
 121 static 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  */
 139 const 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  */
 161 const 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
 179 static 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  */
 215 static 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
 235 static 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
 251 static 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
 282 static 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
 303 static 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  */
 320 static 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
 335 static 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
 348 static 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
 361 static 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
 373 static ssize_t
 374 pci_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
 389 static ssize_t
 390 pci_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
 406 static struct sysfs_ops pci_driver_sysfs_ops = {
 407         .show = pci_driver_attr_show,
 408         .store = pci_driver_attr_store,
 409 };
 410 static 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  */
 425 int __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
 462 void
 463 pci_unregister_driver(struct pci_driver *drv)
 464 {
 465         driver_unregister(&drv->driver);
 466         pci_free_dynids(drv);
 467 }
 468
 469 static 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  */
 480 struct pci_driver *
 481 pci_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  */
 503 static 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  */
 528 struct 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  */
 542 void pci_dev_put(struct pci_dev *dev)
 543 {
 544         if (dev)
 545                 put_device(&dev->dev);
 546 }
 547
 548 #ifndef CONFIG_HOTPLUG
 549 int pci_uevent(struct device *dev, char **envp, int num_envp,
 550                char *buffer, int buffer_size)
 551 {
 552         return -ENODEV;
 553 }
 554 #endif
 555
 556 struct 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
 570 static 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
 576 postcore_initcall(pci_driver_init);
 577
 578 EXPORT_SYMBOL(pci_match_id);
 579 EXPORT_SYMBOL(pci_match_device);
 580 EXPORT_SYMBOL(__pci_register_driver);
 581 EXPORT_SYMBOL(pci_unregister_driver);
 582 EXPORT_SYMBOL(pci_dev_driver);
 583 EXPORT_SYMBOL(pci_bus_type);
 584 EXPORT_SYMBOL(pci_dev_get);
 585 EXPORT_SYMBOL(pci_dev_put);