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