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 "pci.h"
  14
  15 /*
  16  *  Registration of PCI drivers and handling of hot-pluggable devices.
  17  */
  18
  19 /*
  20  * Dynamic device IDs are disabled for !CONFIG_HOTPLUG
  21  */
  22
  23 struct pci_dynid {
  24         struct list_head node;
  25         struct pci_device_id id;
  26 };
  27
  28 #ifdef CONFIG_HOTPLUG
  29
  30 /**
  31  * store_new_id - add a new PCI device ID to this driver and re-probe devices
  32  * @driver: target device driver
  33  * @buf: buffer for scanning device ID data
  34  * @count: input size
  35  *
  36  * Adds a new dynamic pci device ID to this driver,
  37  * and causes the driver to probe for all devices again.
  38  */
  39 static inline ssize_t
  40 store_new_id(struct device_driver *driver, const char *buf, size_t count)
  41 {
  42         struct pci_dynid *dynid;
  43         struct pci_driver *pdrv = to_pci_driver(driver);
  44         __u32 vendor=PCI_ANY_ID, device=PCI_ANY_ID, subvendor=PCI_ANY_ID,
  45                 subdevice=PCI_ANY_ID, class=0, class_mask=0;
  46         unsigned long driver_data=0;
  47         int fields=0;
  48
  49         fields = sscanf(buf, "%x %x %x %x %x %x %lux",
  50                         &vendor, &device, &subvendor, &subdevice,
  51                         &class, &class_mask, &driver_data);
  52         if (fields < 0)
  53                 return -EINVAL;
  54
  55         dynid = kmalloc(sizeof(*dynid), GFP_KERNEL);
  56         if (!dynid)
  57                 return -ENOMEM;
  58
  59         memset(dynid, 0, sizeof(*dynid));
  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         else
 277                 pci_save_state(pci_dev);
 278         return i;
 279 }
 280
 281
 282 /*
 283  * Default resume method for devices that have no driver provided resume,
 284  * or not even a driver at all.
 285  */
 286 static void pci_default_resume(struct pci_dev *pci_dev)
 287 {
 288         int retval;
 289
 290         /* restore the PCI config space */
 291         pci_restore_state(pci_dev);
 292         /* if the device was enabled before suspend, reenable */
 293         if (pci_dev->is_enabled)
 294                 retval = pci_enable_device(pci_dev);
 295         /* if the device was busmaster before the suspend, make it busmaster again */
 296         if (pci_dev->is_busmaster)
 297                 pci_set_master(pci_dev);
 298 }
 299
 300 static int pci_device_resume(struct device * dev)
 301 {
 302         struct pci_dev * pci_dev = to_pci_dev(dev);
 303         struct pci_driver * drv = pci_dev->driver;
 304
 305         if (drv && drv->resume)
 306                 drv->resume(pci_dev);
 307         else
 308                 pci_default_resume(pci_dev);
 309         return 0;
 310 }
 311
 312 static void pci_device_shutdown(struct device *dev)
 313 {
 314         struct pci_dev *pci_dev = to_pci_dev(dev);
 315         struct pci_driver *drv = pci_dev->driver;
 316
 317         if (drv && drv->shutdown)
 318                 drv->shutdown(pci_dev);
 319 }
 320
 321 #define kobj_to_pci_driver(obj) container_of(obj, struct device_driver, kobj)
 322 #define attr_to_driver_attribute(obj) container_of(obj, struct driver_attribute, attr)
 323
 324 static ssize_t
 325 pci_driver_attr_show(struct kobject * kobj, struct attribute *attr, char *buf)
 326 {
 327         struct device_driver *driver = kobj_to_pci_driver(kobj);
 328         struct driver_attribute *dattr = attr_to_driver_attribute(attr);
 329         ssize_t ret;
 330
 331         if (!get_driver(driver))
 332                 return -ENODEV;
 333
 334         ret = dattr->show ? dattr->show(driver, buf) : -EIO;
 335
 336         put_driver(driver);
 337         return ret;
 338 }
 339
 340 static ssize_t
 341 pci_driver_attr_store(struct kobject * kobj, struct attribute *attr,
 342                       const char *buf, size_t count)
 343 {
 344         struct device_driver *driver = kobj_to_pci_driver(kobj);
 345         struct driver_attribute *dattr = attr_to_driver_attribute(attr);
 346         ssize_t ret;
 347
 348         if (!get_driver(driver))
 349                 return -ENODEV;
 350
 351         ret = dattr->store ? dattr->store(driver, buf, count) : -EIO;
 352
 353         put_driver(driver);
 354         return ret;
 355 }
 356
 357 static struct sysfs_ops pci_driver_sysfs_ops = {
 358         .show = pci_driver_attr_show,
 359         .store = pci_driver_attr_store,
 360 };
 361 static struct kobj_type pci_driver_kobj_type = {
 362         .sysfs_ops = &pci_driver_sysfs_ops,
 363 };
 364
 365 /**
 366  * pci_register_driver - register a new pci driver
 367  * @drv: the driver structure to register
 368  *
 369  * Adds the driver structure to the list of registered drivers.
 370  * Returns a negative value on error, otherwise 0.
 371  * If no error occurred, the driver remains registered even if
 372  * no device was claimed during registration.
 373  */
 374 int pci_register_driver(struct pci_driver *drv)
 375 {
 376         int error;
 377
 378         /* initialize common driver fields */
 379         drv->driver.name = drv->name;
 380         drv->driver.bus = &pci_bus_type;
 381         drv->driver.probe = pci_device_probe;
 382         drv->driver.remove = pci_device_remove;
 383         /* FIXME, once all of the existing PCI drivers have been fixed to set
 384          * the pci shutdown function, this test can go away. */
 385         if (!drv->driver.shutdown)
 386                 drv->driver.shutdown = pci_device_shutdown;
 387         else
 388                 printk(KERN_WARNING "Warning: PCI driver %s has a struct "
 389                         "device_driver shutdown method, please update!\n",
 390                         drv->name);
 391         drv->driver.owner = drv->owner;
 392         drv->driver.kobj.ktype = &pci_driver_kobj_type;
 393
 394         spin_lock_init(&drv->dynids.lock);
 395         INIT_LIST_HEAD(&drv->dynids.list);
 396
 397         /* register with core */
 398         error = driver_register(&drv->driver);
 399
 400         if (!error)
 401                 error = pci_create_newid_file(drv);
 402
 403         return error;
 404 }
 405
 406 /**
 407  * pci_unregister_driver - unregister a pci driver
 408  * @drv: the driver structure to unregister
 409  *
 410  * Deletes the driver structure from the list of registered PCI drivers,
 411  * gives it a chance to clean up by calling its remove() function for
 412  * each device it was responsible for, and marks those devices as
 413  * driverless.
 414  */
 415
 416 void
 417 pci_unregister_driver(struct pci_driver *drv)
 418 {
 419         driver_unregister(&drv->driver);
 420         pci_free_dynids(drv);
 421 }
 422
 423 static struct pci_driver pci_compat_driver = {
 424         .name = "compat"
 425 };
 426
 427 /**
 428  * pci_dev_driver - get the pci_driver of a device
 429  * @dev: the device to query
 430  *
 431  * Returns the appropriate pci_driver structure or %NULL if there is no
 432  * registered driver for the device.
 433  */
 434 struct pci_driver *
 435 pci_dev_driver(const struct pci_dev *dev)
 436 {
 437         if (dev->driver)
 438                 return dev->driver;
 439         else {
 440                 int i;
 441                 for(i=0; i<=PCI_ROM_RESOURCE; i++)
 442                         if (dev->resource[i].flags & IORESOURCE_BUSY)
 443                                 return &pci_compat_driver;
 444         }
 445         return NULL;
 446 }
 447
 448 /**
 449  * pci_bus_match - Tell if a PCI device structure has a matching PCI device id structure
 450  * @dev: the PCI device structure to match against
 451  * @drv: the device driver to search for matching PCI device id structures
 452  *
 453  * Used by a driver to check whether a PCI device present in the
 454  * system is in its list of supported devices. Returns the matching
 455  * pci_device_id structure or %NULL if there is no match.
 456  */
 457 static int pci_bus_match(struct device *dev, struct device_driver *drv)
 458 {
 459         struct pci_dev *pci_dev = to_pci_dev(dev);
 460         struct pci_driver *pci_drv = to_pci_driver(drv);
 461         const struct pci_device_id *found_id;
 462
 463         found_id = pci_match_device(pci_drv, pci_dev);
 464         if (found_id)
 465                 return 1;
 466
 467         return 0;
 468 }
 469
 470 /**
 471  * pci_dev_get - increments the reference count of the pci device structure
 472  * @dev: the device being referenced
 473  *
 474  * Each live reference to a device should be refcounted.
 475  *
 476  * Drivers for PCI devices should normally record such references in
 477  * their probe() methods, when they bind to a device, and release
 478  * them by calling pci_dev_put(), in their disconnect() methods.
 479  *
 480  * A pointer to the device with the incremented reference counter is returned.
 481  */
 482 struct pci_dev *pci_dev_get(struct pci_dev *dev)
 483 {
 484         if (dev)
 485                 get_device(&dev->dev);
 486         return dev;
 487 }
 488
 489 /**
 490  * pci_dev_put - release a use of the pci device structure
 491  * @dev: device that's been disconnected
 492  *
 493  * Must be called when a user of a device is finished with it.  When the last
 494  * user of the device calls this function, the memory of the device is freed.
 495  */
 496 void pci_dev_put(struct pci_dev *dev)
 497 {
 498         if (dev)
 499                 put_device(&dev->dev);
 500 }
 501
 502 #ifndef CONFIG_HOTPLUG
 503 int pci_hotplug (struct device *dev, char **envp, int num_envp,
 504                  char *buffer, int buffer_size)
 505 {
 506         return -ENODEV;
 507 }
 508 #endif
 509
 510 struct bus_type pci_bus_type = {
 511         .name           = "pci",
 512         .match          = pci_bus_match,
 513         .hotplug        = pci_hotplug,
 514         .suspend        = pci_device_suspend,
 515         .resume         = pci_device_resume,
 516         .dev_attrs      = pci_dev_attrs,
 517 };
 518
 519 static int __init pci_driver_init(void)
 520 {
 521         return bus_register(&pci_bus_type);
 522 }
 523
 524 postcore_initcall(pci_driver_init);
 525
 526 EXPORT_SYMBOL(pci_match_id);
 527 EXPORT_SYMBOL(pci_match_device);
 528 EXPORT_SYMBOL(pci_register_driver);
 529 EXPORT_SYMBOL(pci_unregister_driver);
 530 EXPORT_SYMBOL(pci_dev_driver);
 531 EXPORT_SYMBOL(pci_bus_type);
 532 EXPORT_SYMBOL(pci_dev_get);
 533 EXPORT_SYMBOL(pci_dev_put);