usb.c 46 KB

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  1. /*
  2. * drivers/usb/usb.c
  3. *
  4. * (C) Copyright Linus Torvalds 1999
  5. * (C) Copyright Johannes Erdfelt 1999-2001
  6. * (C) Copyright Andreas Gal 1999
  7. * (C) Copyright Gregory P. Smith 1999
  8. * (C) Copyright Deti Fliegl 1999 (new USB architecture)
  9. * (C) Copyright Randy Dunlap 2000
  10. * (C) Copyright David Brownell 2000-2004
  11. * (C) Copyright Yggdrasil Computing, Inc. 2000
  12. * (usb_device_id matching changes by Adam J. Richter)
  13. * (C) Copyright Greg Kroah-Hartman 2002-2003
  14. *
  15. * NOTE! This is not actually a driver at all, rather this is
  16. * just a collection of helper routines that implement the
  17. * generic USB things that the real drivers can use..
  18. *
  19. * Think of this as a "USB library" rather than anything else.
  20. * It should be considered a slave, with no callbacks. Callbacks
  21. * are evil.
  22. */
  23. #include <linux/config.h>
  24. #ifdef CONFIG_USB_DEBUG
  25. #define DEBUG
  26. #else
  27. #undef DEBUG
  28. #endif
  29. #include <linux/module.h>
  30. #include <linux/string.h>
  31. #include <linux/bitops.h>
  32. #include <linux/slab.h>
  33. #include <linux/interrupt.h> /* for in_interrupt() */
  34. #include <linux/kmod.h>
  35. #include <linux/init.h>
  36. #include <linux/spinlock.h>
  37. #include <linux/errno.h>
  38. #include <linux/smp_lock.h>
  39. #include <linux/rwsem.h>
  40. #include <linux/usb.h>
  41. #include <asm/io.h>
  42. #include <asm/scatterlist.h>
  43. #include <linux/mm.h>
  44. #include <linux/dma-mapping.h>
  45. #include "hcd.h"
  46. #include "usb.h"
  47. const char *usbcore_name = "usbcore";
  48. static int nousb; /* Disable USB when built into kernel image */
  49. /* Not honored on modular build */
  50. static DECLARE_RWSEM(usb_all_devices_rwsem);
  51. static int generic_probe (struct device *dev)
  52. {
  53. return 0;
  54. }
  55. static int generic_remove (struct device *dev)
  56. {
  57. return 0;
  58. }
  59. static struct device_driver usb_generic_driver = {
  60. .owner = THIS_MODULE,
  61. .name = "usb",
  62. .bus = &usb_bus_type,
  63. .probe = generic_probe,
  64. .remove = generic_remove,
  65. };
  66. static int usb_generic_driver_data;
  67. /* called from driver core with usb_bus_type.subsys writelock */
  68. static int usb_probe_interface(struct device *dev)
  69. {
  70. struct usb_interface * intf = to_usb_interface(dev);
  71. struct usb_driver * driver = to_usb_driver(dev->driver);
  72. const struct usb_device_id *id;
  73. int error = -ENODEV;
  74. dev_dbg(dev, "%s\n", __FUNCTION__);
  75. if (!driver->probe)
  76. return error;
  77. /* FIXME we'd much prefer to just resume it ... */
  78. if (interface_to_usbdev(intf)->state == USB_STATE_SUSPENDED)
  79. return -EHOSTUNREACH;
  80. id = usb_match_id (intf, driver->id_table);
  81. if (id) {
  82. dev_dbg (dev, "%s - got id\n", __FUNCTION__);
  83. intf->condition = USB_INTERFACE_BINDING;
  84. error = driver->probe (intf, id);
  85. intf->condition = error ? USB_INTERFACE_UNBOUND :
  86. USB_INTERFACE_BOUND;
  87. }
  88. return error;
  89. }
  90. /* called from driver core with usb_bus_type.subsys writelock */
  91. static int usb_unbind_interface(struct device *dev)
  92. {
  93. struct usb_interface *intf = to_usb_interface(dev);
  94. struct usb_driver *driver = to_usb_driver(intf->dev.driver);
  95. intf->condition = USB_INTERFACE_UNBINDING;
  96. /* release all urbs for this interface */
  97. usb_disable_interface(interface_to_usbdev(intf), intf);
  98. if (driver && driver->disconnect)
  99. driver->disconnect(intf);
  100. /* reset other interface state */
  101. usb_set_interface(interface_to_usbdev(intf),
  102. intf->altsetting[0].desc.bInterfaceNumber,
  103. 0);
  104. usb_set_intfdata(intf, NULL);
  105. intf->condition = USB_INTERFACE_UNBOUND;
  106. return 0;
  107. }
  108. /**
  109. * usb_register - register a USB driver
  110. * @new_driver: USB operations for the driver
  111. *
  112. * Registers a USB driver with the USB core. The list of unattached
  113. * interfaces will be rescanned whenever a new driver is added, allowing
  114. * the new driver to attach to any recognized devices.
  115. * Returns a negative error code on failure and 0 on success.
  116. *
  117. * NOTE: if you want your driver to use the USB major number, you must call
  118. * usb_register_dev() to enable that functionality. This function no longer
  119. * takes care of that.
  120. */
  121. int usb_register(struct usb_driver *new_driver)
  122. {
  123. int retval = 0;
  124. if (nousb)
  125. return -ENODEV;
  126. new_driver->driver.name = (char *)new_driver->name;
  127. new_driver->driver.bus = &usb_bus_type;
  128. new_driver->driver.probe = usb_probe_interface;
  129. new_driver->driver.remove = usb_unbind_interface;
  130. new_driver->driver.owner = new_driver->owner;
  131. usb_lock_all_devices();
  132. retval = driver_register(&new_driver->driver);
  133. usb_unlock_all_devices();
  134. if (!retval) {
  135. pr_info("%s: registered new driver %s\n",
  136. usbcore_name, new_driver->name);
  137. usbfs_update_special();
  138. } else {
  139. printk(KERN_ERR "%s: error %d registering driver %s\n",
  140. usbcore_name, retval, new_driver->name);
  141. }
  142. return retval;
  143. }
  144. /**
  145. * usb_deregister - unregister a USB driver
  146. * @driver: USB operations of the driver to unregister
  147. * Context: must be able to sleep
  148. *
  149. * Unlinks the specified driver from the internal USB driver list.
  150. *
  151. * NOTE: If you called usb_register_dev(), you still need to call
  152. * usb_deregister_dev() to clean up your driver's allocated minor numbers,
  153. * this * call will no longer do it for you.
  154. */
  155. void usb_deregister(struct usb_driver *driver)
  156. {
  157. pr_info("%s: deregistering driver %s\n", usbcore_name, driver->name);
  158. usb_lock_all_devices();
  159. driver_unregister (&driver->driver);
  160. usb_unlock_all_devices();
  161. usbfs_update_special();
  162. }
  163. /**
  164. * usb_ifnum_to_if - get the interface object with a given interface number
  165. * @dev: the device whose current configuration is considered
  166. * @ifnum: the desired interface
  167. *
  168. * This walks the device descriptor for the currently active configuration
  169. * and returns a pointer to the interface with that particular interface
  170. * number, or null.
  171. *
  172. * Note that configuration descriptors are not required to assign interface
  173. * numbers sequentially, so that it would be incorrect to assume that
  174. * the first interface in that descriptor corresponds to interface zero.
  175. * This routine helps device drivers avoid such mistakes.
  176. * However, you should make sure that you do the right thing with any
  177. * alternate settings available for this interfaces.
  178. *
  179. * Don't call this function unless you are bound to one of the interfaces
  180. * on this device or you have locked the device!
  181. */
  182. struct usb_interface *usb_ifnum_to_if(struct usb_device *dev, unsigned ifnum)
  183. {
  184. struct usb_host_config *config = dev->actconfig;
  185. int i;
  186. if (!config)
  187. return NULL;
  188. for (i = 0; i < config->desc.bNumInterfaces; i++)
  189. if (config->interface[i]->altsetting[0]
  190. .desc.bInterfaceNumber == ifnum)
  191. return config->interface[i];
  192. return NULL;
  193. }
  194. /**
  195. * usb_altnum_to_altsetting - get the altsetting structure with a given
  196. * alternate setting number.
  197. * @intf: the interface containing the altsetting in question
  198. * @altnum: the desired alternate setting number
  199. *
  200. * This searches the altsetting array of the specified interface for
  201. * an entry with the correct bAlternateSetting value and returns a pointer
  202. * to that entry, or null.
  203. *
  204. * Note that altsettings need not be stored sequentially by number, so
  205. * it would be incorrect to assume that the first altsetting entry in
  206. * the array corresponds to altsetting zero. This routine helps device
  207. * drivers avoid such mistakes.
  208. *
  209. * Don't call this function unless you are bound to the intf interface
  210. * or you have locked the device!
  211. */
  212. struct usb_host_interface *usb_altnum_to_altsetting(struct usb_interface *intf,
  213. unsigned int altnum)
  214. {
  215. int i;
  216. for (i = 0; i < intf->num_altsetting; i++) {
  217. if (intf->altsetting[i].desc.bAlternateSetting == altnum)
  218. return &intf->altsetting[i];
  219. }
  220. return NULL;
  221. }
  222. /**
  223. * usb_driver_claim_interface - bind a driver to an interface
  224. * @driver: the driver to be bound
  225. * @iface: the interface to which it will be bound; must be in the
  226. * usb device's active configuration
  227. * @priv: driver data associated with that interface
  228. *
  229. * This is used by usb device drivers that need to claim more than one
  230. * interface on a device when probing (audio and acm are current examples).
  231. * No device driver should directly modify internal usb_interface or
  232. * usb_device structure members.
  233. *
  234. * Few drivers should need to use this routine, since the most natural
  235. * way to bind to an interface is to return the private data from
  236. * the driver's probe() method.
  237. *
  238. * Callers must own the device lock and the driver model's usb_bus_type.subsys
  239. * writelock. So driver probe() entries don't need extra locking,
  240. * but other call contexts may need to explicitly claim those locks.
  241. */
  242. int usb_driver_claim_interface(struct usb_driver *driver,
  243. struct usb_interface *iface, void* priv)
  244. {
  245. struct device *dev = &iface->dev;
  246. if (dev->driver)
  247. return -EBUSY;
  248. dev->driver = &driver->driver;
  249. usb_set_intfdata(iface, priv);
  250. iface->condition = USB_INTERFACE_BOUND;
  251. /* if interface was already added, bind now; else let
  252. * the future device_add() bind it, bypassing probe()
  253. */
  254. if (!list_empty (&dev->bus_list))
  255. device_bind_driver(dev);
  256. return 0;
  257. }
  258. /**
  259. * usb_driver_release_interface - unbind a driver from an interface
  260. * @driver: the driver to be unbound
  261. * @iface: the interface from which it will be unbound
  262. *
  263. * This can be used by drivers to release an interface without waiting
  264. * for their disconnect() methods to be called. In typical cases this
  265. * also causes the driver disconnect() method to be called.
  266. *
  267. * This call is synchronous, and may not be used in an interrupt context.
  268. * Callers must own the device lock and the driver model's usb_bus_type.subsys
  269. * writelock. So driver disconnect() entries don't need extra locking,
  270. * but other call contexts may need to explicitly claim those locks.
  271. */
  272. void usb_driver_release_interface(struct usb_driver *driver,
  273. struct usb_interface *iface)
  274. {
  275. struct device *dev = &iface->dev;
  276. /* this should never happen, don't release something that's not ours */
  277. if (!dev->driver || dev->driver != &driver->driver)
  278. return;
  279. /* don't disconnect from disconnect(), or before dev_add() */
  280. if (!list_empty (&dev->driver_list) && !list_empty (&dev->bus_list))
  281. device_release_driver(dev);
  282. dev->driver = NULL;
  283. usb_set_intfdata(iface, NULL);
  284. iface->condition = USB_INTERFACE_UNBOUND;
  285. }
  286. /**
  287. * usb_match_id - find first usb_device_id matching device or interface
  288. * @interface: the interface of interest
  289. * @id: array of usb_device_id structures, terminated by zero entry
  290. *
  291. * usb_match_id searches an array of usb_device_id's and returns
  292. * the first one matching the device or interface, or null.
  293. * This is used when binding (or rebinding) a driver to an interface.
  294. * Most USB device drivers will use this indirectly, through the usb core,
  295. * but some layered driver frameworks use it directly.
  296. * These device tables are exported with MODULE_DEVICE_TABLE, through
  297. * modutils and "modules.usbmap", to support the driver loading
  298. * functionality of USB hotplugging.
  299. *
  300. * What Matches:
  301. *
  302. * The "match_flags" element in a usb_device_id controls which
  303. * members are used. If the corresponding bit is set, the
  304. * value in the device_id must match its corresponding member
  305. * in the device or interface descriptor, or else the device_id
  306. * does not match.
  307. *
  308. * "driver_info" is normally used only by device drivers,
  309. * but you can create a wildcard "matches anything" usb_device_id
  310. * as a driver's "modules.usbmap" entry if you provide an id with
  311. * only a nonzero "driver_info" field. If you do this, the USB device
  312. * driver's probe() routine should use additional intelligence to
  313. * decide whether to bind to the specified interface.
  314. *
  315. * What Makes Good usb_device_id Tables:
  316. *
  317. * The match algorithm is very simple, so that intelligence in
  318. * driver selection must come from smart driver id records.
  319. * Unless you have good reasons to use another selection policy,
  320. * provide match elements only in related groups, and order match
  321. * specifiers from specific to general. Use the macros provided
  322. * for that purpose if you can.
  323. *
  324. * The most specific match specifiers use device descriptor
  325. * data. These are commonly used with product-specific matches;
  326. * the USB_DEVICE macro lets you provide vendor and product IDs,
  327. * and you can also match against ranges of product revisions.
  328. * These are widely used for devices with application or vendor
  329. * specific bDeviceClass values.
  330. *
  331. * Matches based on device class/subclass/protocol specifications
  332. * are slightly more general; use the USB_DEVICE_INFO macro, or
  333. * its siblings. These are used with single-function devices
  334. * where bDeviceClass doesn't specify that each interface has
  335. * its own class.
  336. *
  337. * Matches based on interface class/subclass/protocol are the
  338. * most general; they let drivers bind to any interface on a
  339. * multiple-function device. Use the USB_INTERFACE_INFO
  340. * macro, or its siblings, to match class-per-interface style
  341. * devices (as recorded in bDeviceClass).
  342. *
  343. * Within those groups, remember that not all combinations are
  344. * meaningful. For example, don't give a product version range
  345. * without vendor and product IDs; or specify a protocol without
  346. * its associated class and subclass.
  347. */
  348. const struct usb_device_id *
  349. usb_match_id(struct usb_interface *interface, const struct usb_device_id *id)
  350. {
  351. struct usb_host_interface *intf;
  352. struct usb_device *dev;
  353. /* proc_connectinfo in devio.c may call us with id == NULL. */
  354. if (id == NULL)
  355. return NULL;
  356. intf = interface->cur_altsetting;
  357. dev = interface_to_usbdev(interface);
  358. /* It is important to check that id->driver_info is nonzero,
  359. since an entry that is all zeroes except for a nonzero
  360. id->driver_info is the way to create an entry that
  361. indicates that the driver want to examine every
  362. device and interface. */
  363. for (; id->idVendor || id->bDeviceClass || id->bInterfaceClass ||
  364. id->driver_info; id++) {
  365. if ((id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
  366. id->idVendor != le16_to_cpu(dev->descriptor.idVendor))
  367. continue;
  368. if ((id->match_flags & USB_DEVICE_ID_MATCH_PRODUCT) &&
  369. id->idProduct != le16_to_cpu(dev->descriptor.idProduct))
  370. continue;
  371. /* No need to test id->bcdDevice_lo != 0, since 0 is never
  372. greater than any unsigned number. */
  373. if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_LO) &&
  374. (id->bcdDevice_lo > le16_to_cpu(dev->descriptor.bcdDevice)))
  375. continue;
  376. if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_HI) &&
  377. (id->bcdDevice_hi < le16_to_cpu(dev->descriptor.bcdDevice)))
  378. continue;
  379. if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_CLASS) &&
  380. (id->bDeviceClass != dev->descriptor.bDeviceClass))
  381. continue;
  382. if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_SUBCLASS) &&
  383. (id->bDeviceSubClass!= dev->descriptor.bDeviceSubClass))
  384. continue;
  385. if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_PROTOCOL) &&
  386. (id->bDeviceProtocol != dev->descriptor.bDeviceProtocol))
  387. continue;
  388. if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_CLASS) &&
  389. (id->bInterfaceClass != intf->desc.bInterfaceClass))
  390. continue;
  391. if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_SUBCLASS) &&
  392. (id->bInterfaceSubClass != intf->desc.bInterfaceSubClass))
  393. continue;
  394. if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_PROTOCOL) &&
  395. (id->bInterfaceProtocol != intf->desc.bInterfaceProtocol))
  396. continue;
  397. return id;
  398. }
  399. return NULL;
  400. }
  401. /**
  402. * usb_find_interface - find usb_interface pointer for driver and device
  403. * @drv: the driver whose current configuration is considered
  404. * @minor: the minor number of the desired device
  405. *
  406. * This walks the driver device list and returns a pointer to the interface
  407. * with the matching minor. Note, this only works for devices that share the
  408. * USB major number.
  409. */
  410. struct usb_interface *usb_find_interface(struct usb_driver *drv, int minor)
  411. {
  412. struct list_head *entry;
  413. struct device *dev;
  414. struct usb_interface *intf;
  415. list_for_each(entry, &drv->driver.devices) {
  416. dev = container_of(entry, struct device, driver_list);
  417. /* can't look at usb devices, only interfaces */
  418. if (dev->driver == &usb_generic_driver)
  419. continue;
  420. intf = to_usb_interface(dev);
  421. if (intf->minor == -1)
  422. continue;
  423. if (intf->minor == minor)
  424. return intf;
  425. }
  426. /* no device found that matches */
  427. return NULL;
  428. }
  429. static int usb_device_match (struct device *dev, struct device_driver *drv)
  430. {
  431. struct usb_interface *intf;
  432. struct usb_driver *usb_drv;
  433. const struct usb_device_id *id;
  434. /* check for generic driver, which we don't match any device with */
  435. if (drv == &usb_generic_driver)
  436. return 0;
  437. intf = to_usb_interface(dev);
  438. usb_drv = to_usb_driver(drv);
  439. id = usb_match_id (intf, usb_drv->id_table);
  440. if (id)
  441. return 1;
  442. return 0;
  443. }
  444. #ifdef CONFIG_HOTPLUG
  445. /*
  446. * USB hotplugging invokes what /proc/sys/kernel/hotplug says
  447. * (normally /sbin/hotplug) when USB devices get added or removed.
  448. *
  449. * This invokes a user mode policy agent, typically helping to load driver
  450. * or other modules, configure the device, and more. Drivers can provide
  451. * a MODULE_DEVICE_TABLE to help with module loading subtasks.
  452. *
  453. * We're called either from khubd (the typical case) or from root hub
  454. * (init, kapmd, modprobe, rmmod, etc), but the agents need to handle
  455. * delays in event delivery. Use sysfs (and DEVPATH) to make sure the
  456. * device (and this configuration!) are still present.
  457. */
  458. static int usb_hotplug (struct device *dev, char **envp, int num_envp,
  459. char *buffer, int buffer_size)
  460. {
  461. struct usb_interface *intf;
  462. struct usb_device *usb_dev;
  463. int i = 0;
  464. int length = 0;
  465. if (!dev)
  466. return -ENODEV;
  467. /* driver is often null here; dev_dbg() would oops */
  468. pr_debug ("usb %s: hotplug\n", dev->bus_id);
  469. /* Must check driver_data here, as on remove driver is always NULL */
  470. if ((dev->driver == &usb_generic_driver) ||
  471. (dev->driver_data == &usb_generic_driver_data))
  472. return 0;
  473. intf = to_usb_interface(dev);
  474. usb_dev = interface_to_usbdev (intf);
  475. if (usb_dev->devnum < 0) {
  476. pr_debug ("usb %s: already deleted?\n", dev->bus_id);
  477. return -ENODEV;
  478. }
  479. if (!usb_dev->bus) {
  480. pr_debug ("usb %s: bus removed?\n", dev->bus_id);
  481. return -ENODEV;
  482. }
  483. #ifdef CONFIG_USB_DEVICEFS
  484. /* If this is available, userspace programs can directly read
  485. * all the device descriptors we don't tell them about. Or
  486. * even act as usermode drivers.
  487. *
  488. * FIXME reduce hardwired intelligence here
  489. */
  490. if (add_hotplug_env_var(envp, num_envp, &i,
  491. buffer, buffer_size, &length,
  492. "DEVICE=/proc/bus/usb/%03d/%03d",
  493. usb_dev->bus->busnum, usb_dev->devnum))
  494. return -ENOMEM;
  495. #endif
  496. /* per-device configurations are common */
  497. if (add_hotplug_env_var(envp, num_envp, &i,
  498. buffer, buffer_size, &length,
  499. "PRODUCT=%x/%x/%x",
  500. le16_to_cpu(usb_dev->descriptor.idVendor),
  501. le16_to_cpu(usb_dev->descriptor.idProduct),
  502. le16_to_cpu(usb_dev->descriptor.bcdDevice)))
  503. return -ENOMEM;
  504. /* class-based driver binding models */
  505. if (add_hotplug_env_var(envp, num_envp, &i,
  506. buffer, buffer_size, &length,
  507. "TYPE=%d/%d/%d",
  508. usb_dev->descriptor.bDeviceClass,
  509. usb_dev->descriptor.bDeviceSubClass,
  510. usb_dev->descriptor.bDeviceProtocol))
  511. return -ENOMEM;
  512. if (usb_dev->descriptor.bDeviceClass == 0) {
  513. struct usb_host_interface *alt = intf->cur_altsetting;
  514. /* 2.4 only exposed interface zero. in 2.5, hotplug
  515. * agents are called for all interfaces, and can use
  516. * $DEVPATH/bInterfaceNumber if necessary.
  517. */
  518. if (add_hotplug_env_var(envp, num_envp, &i,
  519. buffer, buffer_size, &length,
  520. "INTERFACE=%d/%d/%d",
  521. alt->desc.bInterfaceClass,
  522. alt->desc.bInterfaceSubClass,
  523. alt->desc.bInterfaceProtocol))
  524. return -ENOMEM;
  525. if (add_hotplug_env_var(envp, num_envp, &i,
  526. buffer, buffer_size, &length,
  527. "MODALIAS=usb:v%04Xp%04Xd%04Xdc%02Xdsc%02Xdp%02Xic%02Xisc%02Xip%02X",
  528. le16_to_cpu(usb_dev->descriptor.idVendor),
  529. le16_to_cpu(usb_dev->descriptor.idProduct),
  530. le16_to_cpu(usb_dev->descriptor.bcdDevice),
  531. usb_dev->descriptor.bDeviceClass,
  532. usb_dev->descriptor.bDeviceSubClass,
  533. usb_dev->descriptor.bDeviceProtocol,
  534. alt->desc.bInterfaceClass,
  535. alt->desc.bInterfaceSubClass,
  536. alt->desc.bInterfaceProtocol))
  537. return -ENOMEM;
  538. } else {
  539. if (add_hotplug_env_var(envp, num_envp, &i,
  540. buffer, buffer_size, &length,
  541. "MODALIAS=usb:v%04Xp%04Xd%04Xdc%02Xdsc%02Xdp%02Xic*isc*ip*",
  542. le16_to_cpu(usb_dev->descriptor.idVendor),
  543. le16_to_cpu(usb_dev->descriptor.idProduct),
  544. le16_to_cpu(usb_dev->descriptor.bcdDevice),
  545. usb_dev->descriptor.bDeviceClass,
  546. usb_dev->descriptor.bDeviceSubClass,
  547. usb_dev->descriptor.bDeviceProtocol))
  548. return -ENOMEM;
  549. }
  550. envp[i] = NULL;
  551. return 0;
  552. }
  553. #else
  554. static int usb_hotplug (struct device *dev, char **envp,
  555. int num_envp, char *buffer, int buffer_size)
  556. {
  557. return -ENODEV;
  558. }
  559. #endif /* CONFIG_HOTPLUG */
  560. /**
  561. * usb_release_dev - free a usb device structure when all users of it are finished.
  562. * @dev: device that's been disconnected
  563. *
  564. * Will be called only by the device core when all users of this usb device are
  565. * done.
  566. */
  567. static void usb_release_dev(struct device *dev)
  568. {
  569. struct usb_device *udev;
  570. udev = to_usb_device(dev);
  571. usb_destroy_configuration(udev);
  572. usb_bus_put(udev->bus);
  573. kfree(udev->product);
  574. kfree(udev->manufacturer);
  575. kfree(udev->serial);
  576. kfree(udev);
  577. }
  578. /**
  579. * usb_alloc_dev - usb device constructor (usbcore-internal)
  580. * @parent: hub to which device is connected; null to allocate a root hub
  581. * @bus: bus used to access the device
  582. * @port1: one-based index of port; ignored for root hubs
  583. * Context: !in_interrupt ()
  584. *
  585. * Only hub drivers (including virtual root hub drivers for host
  586. * controllers) should ever call this.
  587. *
  588. * This call may not be used in a non-sleeping context.
  589. */
  590. struct usb_device *
  591. usb_alloc_dev(struct usb_device *parent, struct usb_bus *bus, unsigned port1)
  592. {
  593. struct usb_device *dev;
  594. dev = kmalloc(sizeof(*dev), GFP_KERNEL);
  595. if (!dev)
  596. return NULL;
  597. memset(dev, 0, sizeof(*dev));
  598. bus = usb_bus_get(bus);
  599. if (!bus) {
  600. kfree(dev);
  601. return NULL;
  602. }
  603. device_initialize(&dev->dev);
  604. dev->dev.bus = &usb_bus_type;
  605. dev->dev.dma_mask = bus->controller->dma_mask;
  606. dev->dev.driver_data = &usb_generic_driver_data;
  607. dev->dev.driver = &usb_generic_driver;
  608. dev->dev.release = usb_release_dev;
  609. dev->state = USB_STATE_ATTACHED;
  610. INIT_LIST_HEAD(&dev->ep0.urb_list);
  611. dev->ep0.desc.bLength = USB_DT_ENDPOINT_SIZE;
  612. dev->ep0.desc.bDescriptorType = USB_DT_ENDPOINT;
  613. /* ep0 maxpacket comes later, from device descriptor */
  614. dev->ep_in[0] = dev->ep_out[0] = &dev->ep0;
  615. /* Save readable and stable topology id, distinguishing devices
  616. * by location for diagnostics, tools, driver model, etc. The
  617. * string is a path along hub ports, from the root. Each device's
  618. * dev->devpath will be stable until USB is re-cabled, and hubs
  619. * are often labeled with these port numbers. The bus_id isn't
  620. * as stable: bus->busnum changes easily from modprobe order,
  621. * cardbus or pci hotplugging, and so on.
  622. */
  623. if (unlikely (!parent)) {
  624. dev->devpath [0] = '0';
  625. dev->dev.parent = bus->controller;
  626. sprintf (&dev->dev.bus_id[0], "usb%d", bus->busnum);
  627. } else {
  628. /* match any labeling on the hubs; it's one-based */
  629. if (parent->devpath [0] == '0')
  630. snprintf (dev->devpath, sizeof dev->devpath,
  631. "%d", port1);
  632. else
  633. snprintf (dev->devpath, sizeof dev->devpath,
  634. "%s.%d", parent->devpath, port1);
  635. dev->dev.parent = &parent->dev;
  636. sprintf (&dev->dev.bus_id[0], "%d-%s",
  637. bus->busnum, dev->devpath);
  638. /* hub driver sets up TT records */
  639. }
  640. dev->bus = bus;
  641. dev->parent = parent;
  642. INIT_LIST_HEAD(&dev->filelist);
  643. init_MUTEX(&dev->serialize);
  644. return dev;
  645. }
  646. /**
  647. * usb_get_dev - increments the reference count of the usb device structure
  648. * @dev: the device being referenced
  649. *
  650. * Each live reference to a device should be refcounted.
  651. *
  652. * Drivers for USB interfaces should normally record such references in
  653. * their probe() methods, when they bind to an interface, and release
  654. * them by calling usb_put_dev(), in their disconnect() methods.
  655. *
  656. * A pointer to the device with the incremented reference counter is returned.
  657. */
  658. struct usb_device *usb_get_dev(struct usb_device *dev)
  659. {
  660. if (dev)
  661. get_device(&dev->dev);
  662. return dev;
  663. }
  664. /**
  665. * usb_put_dev - release a use of the usb device structure
  666. * @dev: device that's been disconnected
  667. *
  668. * Must be called when a user of a device is finished with it. When the last
  669. * user of the device calls this function, the memory of the device is freed.
  670. */
  671. void usb_put_dev(struct usb_device *dev)
  672. {
  673. if (dev)
  674. put_device(&dev->dev);
  675. }
  676. /**
  677. * usb_get_intf - increments the reference count of the usb interface structure
  678. * @intf: the interface being referenced
  679. *
  680. * Each live reference to a interface must be refcounted.
  681. *
  682. * Drivers for USB interfaces should normally record such references in
  683. * their probe() methods, when they bind to an interface, and release
  684. * them by calling usb_put_intf(), in their disconnect() methods.
  685. *
  686. * A pointer to the interface with the incremented reference counter is
  687. * returned.
  688. */
  689. struct usb_interface *usb_get_intf(struct usb_interface *intf)
  690. {
  691. if (intf)
  692. get_device(&intf->dev);
  693. return intf;
  694. }
  695. /**
  696. * usb_put_intf - release a use of the usb interface structure
  697. * @intf: interface that's been decremented
  698. *
  699. * Must be called when a user of an interface is finished with it. When the
  700. * last user of the interface calls this function, the memory of the interface
  701. * is freed.
  702. */
  703. void usb_put_intf(struct usb_interface *intf)
  704. {
  705. if (intf)
  706. put_device(&intf->dev);
  707. }
  708. /* USB device locking
  709. *
  710. * Although locking USB devices should be straightforward, it is
  711. * complicated by the way the driver-model core works. When a new USB
  712. * driver is registered or unregistered, the core will automatically
  713. * probe or disconnect all matching interfaces on all USB devices while
  714. * holding the USB subsystem writelock. There's no good way for us to
  715. * tell which devices will be used or to lock them beforehand; our only
  716. * option is to effectively lock all the USB devices.
  717. *
  718. * We do that by using a private rw-semaphore, usb_all_devices_rwsem.
  719. * When locking an individual device you must first acquire the rwsem's
  720. * readlock. When a driver is registered or unregistered the writelock
  721. * must be held. These actions are encapsulated in the subroutines
  722. * below, so all a driver needs to do is call usb_lock_device() and
  723. * usb_unlock_device().
  724. *
  725. * Complications arise when several devices are to be locked at the same
  726. * time. Only hub-aware drivers that are part of usbcore ever have to
  727. * do this; nobody else needs to worry about it. The problem is that
  728. * usb_lock_device() must not be called to lock a second device since it
  729. * would acquire the rwsem's readlock reentrantly, leading to deadlock if
  730. * another thread was waiting for the writelock. The solution is simple:
  731. *
  732. * When locking more than one device, call usb_lock_device()
  733. * to lock the first one. Lock the others by calling
  734. * down(&udev->serialize) directly.
  735. *
  736. * When unlocking multiple devices, use up(&udev->serialize)
  737. * to unlock all but the last one. Unlock the last one by
  738. * calling usb_unlock_device().
  739. *
  740. * When locking both a device and its parent, always lock the
  741. * the parent first.
  742. */
  743. /**
  744. * usb_lock_device - acquire the lock for a usb device structure
  745. * @udev: device that's being locked
  746. *
  747. * Use this routine when you don't hold any other device locks;
  748. * to acquire nested inner locks call down(&udev->serialize) directly.
  749. * This is necessary for proper interaction with usb_lock_all_devices().
  750. */
  751. void usb_lock_device(struct usb_device *udev)
  752. {
  753. down_read(&usb_all_devices_rwsem);
  754. down(&udev->serialize);
  755. }
  756. /**
  757. * usb_trylock_device - attempt to acquire the lock for a usb device structure
  758. * @udev: device that's being locked
  759. *
  760. * Don't use this routine if you already hold a device lock;
  761. * use down_trylock(&udev->serialize) instead.
  762. * This is necessary for proper interaction with usb_lock_all_devices().
  763. *
  764. * Returns 1 if successful, 0 if contention.
  765. */
  766. int usb_trylock_device(struct usb_device *udev)
  767. {
  768. if (!down_read_trylock(&usb_all_devices_rwsem))
  769. return 0;
  770. if (down_trylock(&udev->serialize)) {
  771. up_read(&usb_all_devices_rwsem);
  772. return 0;
  773. }
  774. return 1;
  775. }
  776. /**
  777. * usb_lock_device_for_reset - cautiously acquire the lock for a
  778. * usb device structure
  779. * @udev: device that's being locked
  780. * @iface: interface bound to the driver making the request (optional)
  781. *
  782. * Attempts to acquire the device lock, but fails if the device is
  783. * NOTATTACHED or SUSPENDED, or if iface is specified and the interface
  784. * is neither BINDING nor BOUND. Rather than sleeping to wait for the
  785. * lock, the routine polls repeatedly. This is to prevent deadlock with
  786. * disconnect; in some drivers (such as usb-storage) the disconnect()
  787. * callback will block waiting for a device reset to complete.
  788. *
  789. * Returns a negative error code for failure, otherwise 1 or 0 to indicate
  790. * that the device will or will not have to be unlocked. (0 can be
  791. * returned when an interface is given and is BINDING, because in that
  792. * case the driver already owns the device lock.)
  793. */
  794. int usb_lock_device_for_reset(struct usb_device *udev,
  795. struct usb_interface *iface)
  796. {
  797. if (udev->state == USB_STATE_NOTATTACHED)
  798. return -ENODEV;
  799. if (udev->state == USB_STATE_SUSPENDED)
  800. return -EHOSTUNREACH;
  801. if (iface) {
  802. switch (iface->condition) {
  803. case USB_INTERFACE_BINDING:
  804. return 0;
  805. case USB_INTERFACE_BOUND:
  806. break;
  807. default:
  808. return -EINTR;
  809. }
  810. }
  811. while (!usb_trylock_device(udev)) {
  812. msleep(15);
  813. if (udev->state == USB_STATE_NOTATTACHED)
  814. return -ENODEV;
  815. if (udev->state == USB_STATE_SUSPENDED)
  816. return -EHOSTUNREACH;
  817. if (iface && iface->condition != USB_INTERFACE_BOUND)
  818. return -EINTR;
  819. }
  820. return 1;
  821. }
  822. /**
  823. * usb_unlock_device - release the lock for a usb device structure
  824. * @udev: device that's being unlocked
  825. *
  826. * Use this routine when releasing the only device lock you hold;
  827. * to release inner nested locks call up(&udev->serialize) directly.
  828. * This is necessary for proper interaction with usb_lock_all_devices().
  829. */
  830. void usb_unlock_device(struct usb_device *udev)
  831. {
  832. up(&udev->serialize);
  833. up_read(&usb_all_devices_rwsem);
  834. }
  835. /**
  836. * usb_lock_all_devices - acquire the lock for all usb device structures
  837. *
  838. * This is necessary when registering a new driver or probing a bus,
  839. * since the driver-model core may try to use any usb_device.
  840. */
  841. void usb_lock_all_devices(void)
  842. {
  843. down_write(&usb_all_devices_rwsem);
  844. }
  845. /**
  846. * usb_unlock_all_devices - release the lock for all usb device structures
  847. */
  848. void usb_unlock_all_devices(void)
  849. {
  850. up_write(&usb_all_devices_rwsem);
  851. }
  852. static struct usb_device *match_device(struct usb_device *dev,
  853. u16 vendor_id, u16 product_id)
  854. {
  855. struct usb_device *ret_dev = NULL;
  856. int child;
  857. dev_dbg(&dev->dev, "check for vendor %04x, product %04x ...\n",
  858. le16_to_cpu(dev->descriptor.idVendor),
  859. le16_to_cpu(dev->descriptor.idProduct));
  860. /* see if this device matches */
  861. if ((vendor_id == le16_to_cpu(dev->descriptor.idVendor)) &&
  862. (product_id == le16_to_cpu(dev->descriptor.idProduct))) {
  863. dev_dbg (&dev->dev, "matched this device!\n");
  864. ret_dev = usb_get_dev(dev);
  865. goto exit;
  866. }
  867. /* look through all of the children of this device */
  868. for (child = 0; child < dev->maxchild; ++child) {
  869. if (dev->children[child]) {
  870. down(&dev->children[child]->serialize);
  871. ret_dev = match_device(dev->children[child],
  872. vendor_id, product_id);
  873. up(&dev->children[child]->serialize);
  874. if (ret_dev)
  875. goto exit;
  876. }
  877. }
  878. exit:
  879. return ret_dev;
  880. }
  881. /**
  882. * usb_find_device - find a specific usb device in the system
  883. * @vendor_id: the vendor id of the device to find
  884. * @product_id: the product id of the device to find
  885. *
  886. * Returns a pointer to a struct usb_device if such a specified usb
  887. * device is present in the system currently. The usage count of the
  888. * device will be incremented if a device is found. Make sure to call
  889. * usb_put_dev() when the caller is finished with the device.
  890. *
  891. * If a device with the specified vendor and product id is not found,
  892. * NULL is returned.
  893. */
  894. struct usb_device *usb_find_device(u16 vendor_id, u16 product_id)
  895. {
  896. struct list_head *buslist;
  897. struct usb_bus *bus;
  898. struct usb_device *dev = NULL;
  899. down(&usb_bus_list_lock);
  900. for (buslist = usb_bus_list.next;
  901. buslist != &usb_bus_list;
  902. buslist = buslist->next) {
  903. bus = container_of(buslist, struct usb_bus, bus_list);
  904. if (!bus->root_hub)
  905. continue;
  906. usb_lock_device(bus->root_hub);
  907. dev = match_device(bus->root_hub, vendor_id, product_id);
  908. usb_unlock_device(bus->root_hub);
  909. if (dev)
  910. goto exit;
  911. }
  912. exit:
  913. up(&usb_bus_list_lock);
  914. return dev;
  915. }
  916. /**
  917. * usb_get_current_frame_number - return current bus frame number
  918. * @dev: the device whose bus is being queried
  919. *
  920. * Returns the current frame number for the USB host controller
  921. * used with the given USB device. This can be used when scheduling
  922. * isochronous requests.
  923. *
  924. * Note that different kinds of host controller have different
  925. * "scheduling horizons". While one type might support scheduling only
  926. * 32 frames into the future, others could support scheduling up to
  927. * 1024 frames into the future.
  928. */
  929. int usb_get_current_frame_number(struct usb_device *dev)
  930. {
  931. return dev->bus->op->get_frame_number (dev);
  932. }
  933. /*-------------------------------------------------------------------*/
  934. /*
  935. * __usb_get_extra_descriptor() finds a descriptor of specific type in the
  936. * extra field of the interface and endpoint descriptor structs.
  937. */
  938. int __usb_get_extra_descriptor(char *buffer, unsigned size,
  939. unsigned char type, void **ptr)
  940. {
  941. struct usb_descriptor_header *header;
  942. while (size >= sizeof(struct usb_descriptor_header)) {
  943. header = (struct usb_descriptor_header *)buffer;
  944. if (header->bLength < 2) {
  945. printk(KERN_ERR
  946. "%s: bogus descriptor, type %d length %d\n",
  947. usbcore_name,
  948. header->bDescriptorType,
  949. header->bLength);
  950. return -1;
  951. }
  952. if (header->bDescriptorType == type) {
  953. *ptr = header;
  954. return 0;
  955. }
  956. buffer += header->bLength;
  957. size -= header->bLength;
  958. }
  959. return -1;
  960. }
  961. /**
  962. * usb_buffer_alloc - allocate dma-consistent buffer for URB_NO_xxx_DMA_MAP
  963. * @dev: device the buffer will be used with
  964. * @size: requested buffer size
  965. * @mem_flags: affect whether allocation may block
  966. * @dma: used to return DMA address of buffer
  967. *
  968. * Return value is either null (indicating no buffer could be allocated), or
  969. * the cpu-space pointer to a buffer that may be used to perform DMA to the
  970. * specified device. Such cpu-space buffers are returned along with the DMA
  971. * address (through the pointer provided).
  972. *
  973. * These buffers are used with URB_NO_xxx_DMA_MAP set in urb->transfer_flags
  974. * to avoid behaviors like using "DMA bounce buffers", or tying down I/O
  975. * mapping hardware for long idle periods. The implementation varies between
  976. * platforms, depending on details of how DMA will work to this device.
  977. * Using these buffers also helps prevent cacheline sharing problems on
  978. * architectures where CPU caches are not DMA-coherent.
  979. *
  980. * When the buffer is no longer used, free it with usb_buffer_free().
  981. */
  982. void *usb_buffer_alloc (
  983. struct usb_device *dev,
  984. size_t size,
  985. int mem_flags,
  986. dma_addr_t *dma
  987. )
  988. {
  989. if (!dev || !dev->bus || !dev->bus->op || !dev->bus->op->buffer_alloc)
  990. return NULL;
  991. return dev->bus->op->buffer_alloc (dev->bus, size, mem_flags, dma);
  992. }
  993. /**
  994. * usb_buffer_free - free memory allocated with usb_buffer_alloc()
  995. * @dev: device the buffer was used with
  996. * @size: requested buffer size
  997. * @addr: CPU address of buffer
  998. * @dma: DMA address of buffer
  999. *
  1000. * This reclaims an I/O buffer, letting it be reused. The memory must have
  1001. * been allocated using usb_buffer_alloc(), and the parameters must match
  1002. * those provided in that allocation request.
  1003. */
  1004. void usb_buffer_free (
  1005. struct usb_device *dev,
  1006. size_t size,
  1007. void *addr,
  1008. dma_addr_t dma
  1009. )
  1010. {
  1011. if (!dev || !dev->bus || !dev->bus->op || !dev->bus->op->buffer_free)
  1012. return;
  1013. dev->bus->op->buffer_free (dev->bus, size, addr, dma);
  1014. }
  1015. /**
  1016. * usb_buffer_map - create DMA mapping(s) for an urb
  1017. * @urb: urb whose transfer_buffer/setup_packet will be mapped
  1018. *
  1019. * Return value is either null (indicating no buffer could be mapped), or
  1020. * the parameter. URB_NO_TRANSFER_DMA_MAP and URB_NO_SETUP_DMA_MAP are
  1021. * added to urb->transfer_flags if the operation succeeds. If the device
  1022. * is connected to this system through a non-DMA controller, this operation
  1023. * always succeeds.
  1024. *
  1025. * This call would normally be used for an urb which is reused, perhaps
  1026. * as the target of a large periodic transfer, with usb_buffer_dmasync()
  1027. * calls to synchronize memory and dma state.
  1028. *
  1029. * Reverse the effect of this call with usb_buffer_unmap().
  1030. */
  1031. #if 0
  1032. struct urb *usb_buffer_map (struct urb *urb)
  1033. {
  1034. struct usb_bus *bus;
  1035. struct device *controller;
  1036. if (!urb
  1037. || !urb->dev
  1038. || !(bus = urb->dev->bus)
  1039. || !(controller = bus->controller))
  1040. return NULL;
  1041. if (controller->dma_mask) {
  1042. urb->transfer_dma = dma_map_single (controller,
  1043. urb->transfer_buffer, urb->transfer_buffer_length,
  1044. usb_pipein (urb->pipe)
  1045. ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
  1046. if (usb_pipecontrol (urb->pipe))
  1047. urb->setup_dma = dma_map_single (controller,
  1048. urb->setup_packet,
  1049. sizeof (struct usb_ctrlrequest),
  1050. DMA_TO_DEVICE);
  1051. // FIXME generic api broken like pci, can't report errors
  1052. // if (urb->transfer_dma == DMA_ADDR_INVALID) return 0;
  1053. } else
  1054. urb->transfer_dma = ~0;
  1055. urb->transfer_flags |= (URB_NO_TRANSFER_DMA_MAP
  1056. | URB_NO_SETUP_DMA_MAP);
  1057. return urb;
  1058. }
  1059. #endif /* 0 */
  1060. /* XXX DISABLED, no users currently. If you wish to re-enable this
  1061. * XXX please determine whether the sync is to transfer ownership of
  1062. * XXX the buffer from device to cpu or vice verse, and thusly use the
  1063. * XXX appropriate _for_{cpu,device}() method. -DaveM
  1064. */
  1065. #if 0
  1066. /**
  1067. * usb_buffer_dmasync - synchronize DMA and CPU view of buffer(s)
  1068. * @urb: urb whose transfer_buffer/setup_packet will be synchronized
  1069. */
  1070. void usb_buffer_dmasync (struct urb *urb)
  1071. {
  1072. struct usb_bus *bus;
  1073. struct device *controller;
  1074. if (!urb
  1075. || !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)
  1076. || !urb->dev
  1077. || !(bus = urb->dev->bus)
  1078. || !(controller = bus->controller))
  1079. return;
  1080. if (controller->dma_mask) {
  1081. dma_sync_single (controller,
  1082. urb->transfer_dma, urb->transfer_buffer_length,
  1083. usb_pipein (urb->pipe)
  1084. ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
  1085. if (usb_pipecontrol (urb->pipe))
  1086. dma_sync_single (controller,
  1087. urb->setup_dma,
  1088. sizeof (struct usb_ctrlrequest),
  1089. DMA_TO_DEVICE);
  1090. }
  1091. }
  1092. #endif
  1093. /**
  1094. * usb_buffer_unmap - free DMA mapping(s) for an urb
  1095. * @urb: urb whose transfer_buffer will be unmapped
  1096. *
  1097. * Reverses the effect of usb_buffer_map().
  1098. */
  1099. #if 0
  1100. void usb_buffer_unmap (struct urb *urb)
  1101. {
  1102. struct usb_bus *bus;
  1103. struct device *controller;
  1104. if (!urb
  1105. || !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)
  1106. || !urb->dev
  1107. || !(bus = urb->dev->bus)
  1108. || !(controller = bus->controller))
  1109. return;
  1110. if (controller->dma_mask) {
  1111. dma_unmap_single (controller,
  1112. urb->transfer_dma, urb->transfer_buffer_length,
  1113. usb_pipein (urb->pipe)
  1114. ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
  1115. if (usb_pipecontrol (urb->pipe))
  1116. dma_unmap_single (controller,
  1117. urb->setup_dma,
  1118. sizeof (struct usb_ctrlrequest),
  1119. DMA_TO_DEVICE);
  1120. }
  1121. urb->transfer_flags &= ~(URB_NO_TRANSFER_DMA_MAP
  1122. | URB_NO_SETUP_DMA_MAP);
  1123. }
  1124. #endif /* 0 */
  1125. /**
  1126. * usb_buffer_map_sg - create scatterlist DMA mapping(s) for an endpoint
  1127. * @dev: device to which the scatterlist will be mapped
  1128. * @pipe: endpoint defining the mapping direction
  1129. * @sg: the scatterlist to map
  1130. * @nents: the number of entries in the scatterlist
  1131. *
  1132. * Return value is either < 0 (indicating no buffers could be mapped), or
  1133. * the number of DMA mapping array entries in the scatterlist.
  1134. *
  1135. * The caller is responsible for placing the resulting DMA addresses from
  1136. * the scatterlist into URB transfer buffer pointers, and for setting the
  1137. * URB_NO_TRANSFER_DMA_MAP transfer flag in each of those URBs.
  1138. *
  1139. * Top I/O rates come from queuing URBs, instead of waiting for each one
  1140. * to complete before starting the next I/O. This is particularly easy
  1141. * to do with scatterlists. Just allocate and submit one URB for each DMA
  1142. * mapping entry returned, stopping on the first error or when all succeed.
  1143. * Better yet, use the usb_sg_*() calls, which do that (and more) for you.
  1144. *
  1145. * This call would normally be used when translating scatterlist requests,
  1146. * rather than usb_buffer_map(), since on some hardware (with IOMMUs) it
  1147. * may be able to coalesce mappings for improved I/O efficiency.
  1148. *
  1149. * Reverse the effect of this call with usb_buffer_unmap_sg().
  1150. */
  1151. int usb_buffer_map_sg (struct usb_device *dev, unsigned pipe,
  1152. struct scatterlist *sg, int nents)
  1153. {
  1154. struct usb_bus *bus;
  1155. struct device *controller;
  1156. if (!dev
  1157. || usb_pipecontrol (pipe)
  1158. || !(bus = dev->bus)
  1159. || !(controller = bus->controller)
  1160. || !controller->dma_mask)
  1161. return -1;
  1162. // FIXME generic api broken like pci, can't report errors
  1163. return dma_map_sg (controller, sg, nents,
  1164. usb_pipein (pipe) ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
  1165. }
  1166. /* XXX DISABLED, no users currently. If you wish to re-enable this
  1167. * XXX please determine whether the sync is to transfer ownership of
  1168. * XXX the buffer from device to cpu or vice verse, and thusly use the
  1169. * XXX appropriate _for_{cpu,device}() method. -DaveM
  1170. */
  1171. #if 0
  1172. /**
  1173. * usb_buffer_dmasync_sg - synchronize DMA and CPU view of scatterlist buffer(s)
  1174. * @dev: device to which the scatterlist will be mapped
  1175. * @pipe: endpoint defining the mapping direction
  1176. * @sg: the scatterlist to synchronize
  1177. * @n_hw_ents: the positive return value from usb_buffer_map_sg
  1178. *
  1179. * Use this when you are re-using a scatterlist's data buffers for
  1180. * another USB request.
  1181. */
  1182. void usb_buffer_dmasync_sg (struct usb_device *dev, unsigned pipe,
  1183. struct scatterlist *sg, int n_hw_ents)
  1184. {
  1185. struct usb_bus *bus;
  1186. struct device *controller;
  1187. if (!dev
  1188. || !(bus = dev->bus)
  1189. || !(controller = bus->controller)
  1190. || !controller->dma_mask)
  1191. return;
  1192. dma_sync_sg (controller, sg, n_hw_ents,
  1193. usb_pipein (pipe) ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
  1194. }
  1195. #endif
  1196. /**
  1197. * usb_buffer_unmap_sg - free DMA mapping(s) for a scatterlist
  1198. * @dev: device to which the scatterlist will be mapped
  1199. * @pipe: endpoint defining the mapping direction
  1200. * @sg: the scatterlist to unmap
  1201. * @n_hw_ents: the positive return value from usb_buffer_map_sg
  1202. *
  1203. * Reverses the effect of usb_buffer_map_sg().
  1204. */
  1205. void usb_buffer_unmap_sg (struct usb_device *dev, unsigned pipe,
  1206. struct scatterlist *sg, int n_hw_ents)
  1207. {
  1208. struct usb_bus *bus;
  1209. struct device *controller;
  1210. if (!dev
  1211. || !(bus = dev->bus)
  1212. || !(controller = bus->controller)
  1213. || !controller->dma_mask)
  1214. return;
  1215. dma_unmap_sg (controller, sg, n_hw_ents,
  1216. usb_pipein (pipe) ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
  1217. }
  1218. static int usb_generic_suspend(struct device *dev, pm_message_t message)
  1219. {
  1220. struct usb_interface *intf;
  1221. struct usb_driver *driver;
  1222. if (dev->driver == &usb_generic_driver)
  1223. return usb_suspend_device (to_usb_device(dev), message);
  1224. if ((dev->driver == NULL) ||
  1225. (dev->driver_data == &usb_generic_driver_data))
  1226. return 0;
  1227. intf = to_usb_interface(dev);
  1228. driver = to_usb_driver(dev->driver);
  1229. /* there's only one USB suspend state */
  1230. if (intf->dev.power.power_state)
  1231. return 0;
  1232. if (driver->suspend)
  1233. return driver->suspend(intf, message);
  1234. return 0;
  1235. }
  1236. static int usb_generic_resume(struct device *dev)
  1237. {
  1238. struct usb_interface *intf;
  1239. struct usb_driver *driver;
  1240. /* devices resume through their hub */
  1241. if (dev->driver == &usb_generic_driver)
  1242. return usb_resume_device (to_usb_device(dev));
  1243. if ((dev->driver == NULL) ||
  1244. (dev->driver_data == &usb_generic_driver_data))
  1245. return 0;
  1246. intf = to_usb_interface(dev);
  1247. driver = to_usb_driver(dev->driver);
  1248. if (driver->resume)
  1249. return driver->resume(intf);
  1250. return 0;
  1251. }
  1252. struct bus_type usb_bus_type = {
  1253. .name = "usb",
  1254. .match = usb_device_match,
  1255. .hotplug = usb_hotplug,
  1256. .suspend = usb_generic_suspend,
  1257. .resume = usb_generic_resume,
  1258. };
  1259. #ifndef MODULE
  1260. static int __init usb_setup_disable(char *str)
  1261. {
  1262. nousb = 1;
  1263. return 1;
  1264. }
  1265. /* format to disable USB on kernel command line is: nousb */
  1266. __setup("nousb", usb_setup_disable);
  1267. #endif
  1268. /*
  1269. * for external read access to <nousb>
  1270. */
  1271. int usb_disabled(void)
  1272. {
  1273. return nousb;
  1274. }
  1275. /*
  1276. * Init
  1277. */
  1278. static int __init usb_init(void)
  1279. {
  1280. int retval;
  1281. if (nousb) {
  1282. pr_info ("%s: USB support disabled\n", usbcore_name);
  1283. return 0;
  1284. }
  1285. retval = bus_register(&usb_bus_type);
  1286. if (retval)
  1287. goto out;
  1288. retval = usb_host_init();
  1289. if (retval)
  1290. goto host_init_failed;
  1291. retval = usb_major_init();
  1292. if (retval)
  1293. goto major_init_failed;
  1294. retval = usbfs_init();
  1295. if (retval)
  1296. goto fs_init_failed;
  1297. retval = usb_hub_init();
  1298. if (retval)
  1299. goto hub_init_failed;
  1300. retval = driver_register(&usb_generic_driver);
  1301. if (!retval)
  1302. goto out;
  1303. usb_hub_cleanup();
  1304. hub_init_failed:
  1305. usbfs_cleanup();
  1306. fs_init_failed:
  1307. usb_major_cleanup();
  1308. major_init_failed:
  1309. usb_host_cleanup();
  1310. host_init_failed:
  1311. bus_unregister(&usb_bus_type);
  1312. out:
  1313. return retval;
  1314. }
  1315. /*
  1316. * Cleanup
  1317. */
  1318. static void __exit usb_exit(void)
  1319. {
  1320. /* This will matter if shutdown/reboot does exitcalls. */
  1321. if (nousb)
  1322. return;
  1323. driver_unregister(&usb_generic_driver);
  1324. usb_major_cleanup();
  1325. usbfs_cleanup();
  1326. usb_hub_cleanup();
  1327. usb_host_cleanup();
  1328. bus_unregister(&usb_bus_type);
  1329. }
  1330. subsys_initcall(usb_init);
  1331. module_exit(usb_exit);
  1332. /*
  1333. * USB may be built into the kernel or be built as modules.
  1334. * These symbols are exported for device (or host controller)
  1335. * driver modules to use.
  1336. */
  1337. EXPORT_SYMBOL(usb_register);
  1338. EXPORT_SYMBOL(usb_deregister);
  1339. EXPORT_SYMBOL(usb_disabled);
  1340. EXPORT_SYMBOL(usb_alloc_dev);
  1341. EXPORT_SYMBOL(usb_put_dev);
  1342. EXPORT_SYMBOL(usb_get_dev);
  1343. EXPORT_SYMBOL(usb_hub_tt_clear_buffer);
  1344. EXPORT_SYMBOL(usb_lock_device);
  1345. EXPORT_SYMBOL(usb_trylock_device);
  1346. EXPORT_SYMBOL(usb_lock_device_for_reset);
  1347. EXPORT_SYMBOL(usb_unlock_device);
  1348. EXPORT_SYMBOL(usb_driver_claim_interface);
  1349. EXPORT_SYMBOL(usb_driver_release_interface);
  1350. EXPORT_SYMBOL(usb_match_id);
  1351. EXPORT_SYMBOL(usb_find_interface);
  1352. EXPORT_SYMBOL(usb_ifnum_to_if);
  1353. EXPORT_SYMBOL(usb_altnum_to_altsetting);
  1354. EXPORT_SYMBOL(usb_reset_device);
  1355. EXPORT_SYMBOL(usb_disconnect);
  1356. EXPORT_SYMBOL(__usb_get_extra_descriptor);
  1357. EXPORT_SYMBOL(usb_find_device);
  1358. EXPORT_SYMBOL(usb_get_current_frame_number);
  1359. EXPORT_SYMBOL (usb_buffer_alloc);
  1360. EXPORT_SYMBOL (usb_buffer_free);
  1361. #if 0
  1362. EXPORT_SYMBOL (usb_buffer_map);
  1363. EXPORT_SYMBOL (usb_buffer_dmasync);
  1364. EXPORT_SYMBOL (usb_buffer_unmap);
  1365. #endif
  1366. EXPORT_SYMBOL (usb_buffer_map_sg);
  1367. #if 0
  1368. EXPORT_SYMBOL (usb_buffer_dmasync_sg);
  1369. #endif
  1370. EXPORT_SYMBOL (usb_buffer_unmap_sg);
  1371. MODULE_LICENSE("GPL");