hcd.c 66 KB

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  1. /*
  2. * (C) Copyright Linus Torvalds 1999
  3. * (C) Copyright Johannes Erdfelt 1999-2001
  4. * (C) Copyright Andreas Gal 1999
  5. * (C) Copyright Gregory P. Smith 1999
  6. * (C) Copyright Deti Fliegl 1999
  7. * (C) Copyright Randy Dunlap 2000
  8. * (C) Copyright David Brownell 2000-2002
  9. *
  10. * This program is free software; you can redistribute it and/or modify it
  11. * under the terms of the GNU General Public License as published by the
  12. * Free Software Foundation; either version 2 of the License, or (at your
  13. * option) any later version.
  14. *
  15. * This program is distributed in the hope that it will be useful, but
  16. * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  17. * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
  18. * for more details.
  19. *
  20. * You should have received a copy of the GNU General Public License
  21. * along with this program; if not, write to the Free Software Foundation,
  22. * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  23. */
  24. #include <linux/module.h>
  25. #include <linux/version.h>
  26. #include <linux/kernel.h>
  27. #include <linux/slab.h>
  28. #include <linux/completion.h>
  29. #include <linux/utsname.h>
  30. #include <linux/mm.h>
  31. #include <asm/io.h>
  32. #include <linux/device.h>
  33. #include <linux/dma-mapping.h>
  34. #include <linux/mutex.h>
  35. #include <asm/irq.h>
  36. #include <asm/byteorder.h>
  37. #include <asm/unaligned.h>
  38. #include <linux/platform_device.h>
  39. #include <linux/workqueue.h>
  40. #include <linux/mutex.h>
  41. #include <linux/usb.h>
  42. #include "usb.h"
  43. #include "hcd.h"
  44. #include "hub.h"
  45. /*-------------------------------------------------------------------------*/
  46. /*
  47. * USB Host Controller Driver framework
  48. *
  49. * Plugs into usbcore (usb_bus) and lets HCDs share code, minimizing
  50. * HCD-specific behaviors/bugs.
  51. *
  52. * This does error checks, tracks devices and urbs, and delegates to a
  53. * "hc_driver" only for code (and data) that really needs to know about
  54. * hardware differences. That includes root hub registers, i/o queues,
  55. * and so on ... but as little else as possible.
  56. *
  57. * Shared code includes most of the "root hub" code (these are emulated,
  58. * though each HC's hardware works differently) and PCI glue, plus request
  59. * tracking overhead. The HCD code should only block on spinlocks or on
  60. * hardware handshaking; blocking on software events (such as other kernel
  61. * threads releasing resources, or completing actions) is all generic.
  62. *
  63. * Happens the USB 2.0 spec says this would be invisible inside the "USBD",
  64. * and includes mostly a "HCDI" (HCD Interface) along with some APIs used
  65. * only by the hub driver ... and that neither should be seen or used by
  66. * usb client device drivers.
  67. *
  68. * Contributors of ideas or unattributed patches include: David Brownell,
  69. * Roman Weissgaerber, Rory Bolt, Greg Kroah-Hartman, ...
  70. *
  71. * HISTORY:
  72. * 2002-02-21 Pull in most of the usb_bus support from usb.c; some
  73. * associated cleanup. "usb_hcd" still != "usb_bus".
  74. * 2001-12-12 Initial patch version for Linux 2.5.1 kernel.
  75. */
  76. /*-------------------------------------------------------------------------*/
  77. /* Keep track of which host controller drivers are loaded */
  78. unsigned long usb_hcds_loaded;
  79. EXPORT_SYMBOL_GPL(usb_hcds_loaded);
  80. /* host controllers we manage */
  81. LIST_HEAD (usb_bus_list);
  82. EXPORT_SYMBOL_GPL (usb_bus_list);
  83. /* used when allocating bus numbers */
  84. #define USB_MAXBUS 64
  85. struct usb_busmap {
  86. unsigned long busmap [USB_MAXBUS / (8*sizeof (unsigned long))];
  87. };
  88. static struct usb_busmap busmap;
  89. /* used when updating list of hcds */
  90. DEFINE_MUTEX(usb_bus_list_lock); /* exported only for usbfs */
  91. EXPORT_SYMBOL_GPL (usb_bus_list_lock);
  92. /* used for controlling access to virtual root hubs */
  93. static DEFINE_SPINLOCK(hcd_root_hub_lock);
  94. /* used when updating an endpoint's URB list */
  95. static DEFINE_SPINLOCK(hcd_urb_list_lock);
  96. /* used to protect against unlinking URBs after the device is gone */
  97. static DEFINE_SPINLOCK(hcd_urb_unlink_lock);
  98. /* wait queue for synchronous unlinks */
  99. DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue);
  100. static inline int is_root_hub(struct usb_device *udev)
  101. {
  102. return (udev->parent == NULL);
  103. }
  104. /*-------------------------------------------------------------------------*/
  105. /*
  106. * Sharable chunks of root hub code.
  107. */
  108. /*-------------------------------------------------------------------------*/
  109. #define KERNEL_REL ((LINUX_VERSION_CODE >> 16) & 0x0ff)
  110. #define KERNEL_VER ((LINUX_VERSION_CODE >> 8) & 0x0ff)
  111. /* usb 3.0 root hub device descriptor */
  112. static const u8 usb3_rh_dev_descriptor[18] = {
  113. 0x12, /* __u8 bLength; */
  114. 0x01, /* __u8 bDescriptorType; Device */
  115. 0x00, 0x03, /* __le16 bcdUSB; v3.0 */
  116. 0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */
  117. 0x00, /* __u8 bDeviceSubClass; */
  118. 0x03, /* __u8 bDeviceProtocol; USB 3.0 hub */
  119. 0x09, /* __u8 bMaxPacketSize0; 2^9 = 512 Bytes */
  120. 0x6b, 0x1d, /* __le16 idVendor; Linux Foundation */
  121. 0x02, 0x00, /* __le16 idProduct; device 0x0002 */
  122. KERNEL_VER, KERNEL_REL, /* __le16 bcdDevice */
  123. 0x03, /* __u8 iManufacturer; */
  124. 0x02, /* __u8 iProduct; */
  125. 0x01, /* __u8 iSerialNumber; */
  126. 0x01 /* __u8 bNumConfigurations; */
  127. };
  128. /* usb 2.0 root hub device descriptor */
  129. static const u8 usb2_rh_dev_descriptor [18] = {
  130. 0x12, /* __u8 bLength; */
  131. 0x01, /* __u8 bDescriptorType; Device */
  132. 0x00, 0x02, /* __le16 bcdUSB; v2.0 */
  133. 0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */
  134. 0x00, /* __u8 bDeviceSubClass; */
  135. 0x00, /* __u8 bDeviceProtocol; [ usb 2.0 no TT ] */
  136. 0x40, /* __u8 bMaxPacketSize0; 64 Bytes */
  137. 0x6b, 0x1d, /* __le16 idVendor; Linux Foundation */
  138. 0x02, 0x00, /* __le16 idProduct; device 0x0002 */
  139. KERNEL_VER, KERNEL_REL, /* __le16 bcdDevice */
  140. 0x03, /* __u8 iManufacturer; */
  141. 0x02, /* __u8 iProduct; */
  142. 0x01, /* __u8 iSerialNumber; */
  143. 0x01 /* __u8 bNumConfigurations; */
  144. };
  145. /* no usb 2.0 root hub "device qualifier" descriptor: one speed only */
  146. /* usb 1.1 root hub device descriptor */
  147. static const u8 usb11_rh_dev_descriptor [18] = {
  148. 0x12, /* __u8 bLength; */
  149. 0x01, /* __u8 bDescriptorType; Device */
  150. 0x10, 0x01, /* __le16 bcdUSB; v1.1 */
  151. 0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */
  152. 0x00, /* __u8 bDeviceSubClass; */
  153. 0x00, /* __u8 bDeviceProtocol; [ low/full speeds only ] */
  154. 0x40, /* __u8 bMaxPacketSize0; 64 Bytes */
  155. 0x6b, 0x1d, /* __le16 idVendor; Linux Foundation */
  156. 0x01, 0x00, /* __le16 idProduct; device 0x0001 */
  157. KERNEL_VER, KERNEL_REL, /* __le16 bcdDevice */
  158. 0x03, /* __u8 iManufacturer; */
  159. 0x02, /* __u8 iProduct; */
  160. 0x01, /* __u8 iSerialNumber; */
  161. 0x01 /* __u8 bNumConfigurations; */
  162. };
  163. /*-------------------------------------------------------------------------*/
  164. /* Configuration descriptors for our root hubs */
  165. static const u8 fs_rh_config_descriptor [] = {
  166. /* one configuration */
  167. 0x09, /* __u8 bLength; */
  168. 0x02, /* __u8 bDescriptorType; Configuration */
  169. 0x19, 0x00, /* __le16 wTotalLength; */
  170. 0x01, /* __u8 bNumInterfaces; (1) */
  171. 0x01, /* __u8 bConfigurationValue; */
  172. 0x00, /* __u8 iConfiguration; */
  173. 0xc0, /* __u8 bmAttributes;
  174. Bit 7: must be set,
  175. 6: Self-powered,
  176. 5: Remote wakeup,
  177. 4..0: resvd */
  178. 0x00, /* __u8 MaxPower; */
  179. /* USB 1.1:
  180. * USB 2.0, single TT organization (mandatory):
  181. * one interface, protocol 0
  182. *
  183. * USB 2.0, multiple TT organization (optional):
  184. * two interfaces, protocols 1 (like single TT)
  185. * and 2 (multiple TT mode) ... config is
  186. * sometimes settable
  187. * NOT IMPLEMENTED
  188. */
  189. /* one interface */
  190. 0x09, /* __u8 if_bLength; */
  191. 0x04, /* __u8 if_bDescriptorType; Interface */
  192. 0x00, /* __u8 if_bInterfaceNumber; */
  193. 0x00, /* __u8 if_bAlternateSetting; */
  194. 0x01, /* __u8 if_bNumEndpoints; */
  195. 0x09, /* __u8 if_bInterfaceClass; HUB_CLASSCODE */
  196. 0x00, /* __u8 if_bInterfaceSubClass; */
  197. 0x00, /* __u8 if_bInterfaceProtocol; [usb1.1 or single tt] */
  198. 0x00, /* __u8 if_iInterface; */
  199. /* one endpoint (status change endpoint) */
  200. 0x07, /* __u8 ep_bLength; */
  201. 0x05, /* __u8 ep_bDescriptorType; Endpoint */
  202. 0x81, /* __u8 ep_bEndpointAddress; IN Endpoint 1 */
  203. 0x03, /* __u8 ep_bmAttributes; Interrupt */
  204. 0x02, 0x00, /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */
  205. 0xff /* __u8 ep_bInterval; (255ms -- usb 2.0 spec) */
  206. };
  207. static const u8 hs_rh_config_descriptor [] = {
  208. /* one configuration */
  209. 0x09, /* __u8 bLength; */
  210. 0x02, /* __u8 bDescriptorType; Configuration */
  211. 0x19, 0x00, /* __le16 wTotalLength; */
  212. 0x01, /* __u8 bNumInterfaces; (1) */
  213. 0x01, /* __u8 bConfigurationValue; */
  214. 0x00, /* __u8 iConfiguration; */
  215. 0xc0, /* __u8 bmAttributes;
  216. Bit 7: must be set,
  217. 6: Self-powered,
  218. 5: Remote wakeup,
  219. 4..0: resvd */
  220. 0x00, /* __u8 MaxPower; */
  221. /* USB 1.1:
  222. * USB 2.0, single TT organization (mandatory):
  223. * one interface, protocol 0
  224. *
  225. * USB 2.0, multiple TT organization (optional):
  226. * two interfaces, protocols 1 (like single TT)
  227. * and 2 (multiple TT mode) ... config is
  228. * sometimes settable
  229. * NOT IMPLEMENTED
  230. */
  231. /* one interface */
  232. 0x09, /* __u8 if_bLength; */
  233. 0x04, /* __u8 if_bDescriptorType; Interface */
  234. 0x00, /* __u8 if_bInterfaceNumber; */
  235. 0x00, /* __u8 if_bAlternateSetting; */
  236. 0x01, /* __u8 if_bNumEndpoints; */
  237. 0x09, /* __u8 if_bInterfaceClass; HUB_CLASSCODE */
  238. 0x00, /* __u8 if_bInterfaceSubClass; */
  239. 0x00, /* __u8 if_bInterfaceProtocol; [usb1.1 or single tt] */
  240. 0x00, /* __u8 if_iInterface; */
  241. /* one endpoint (status change endpoint) */
  242. 0x07, /* __u8 ep_bLength; */
  243. 0x05, /* __u8 ep_bDescriptorType; Endpoint */
  244. 0x81, /* __u8 ep_bEndpointAddress; IN Endpoint 1 */
  245. 0x03, /* __u8 ep_bmAttributes; Interrupt */
  246. /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
  247. * see hub.c:hub_configure() for details. */
  248. (USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
  249. 0x0c /* __u8 ep_bInterval; (256ms -- usb 2.0 spec) */
  250. };
  251. static const u8 ss_rh_config_descriptor[] = {
  252. /* one configuration */
  253. 0x09, /* __u8 bLength; */
  254. 0x02, /* __u8 bDescriptorType; Configuration */
  255. 0x19, 0x00, /* __le16 wTotalLength; FIXME */
  256. 0x01, /* __u8 bNumInterfaces; (1) */
  257. 0x01, /* __u8 bConfigurationValue; */
  258. 0x00, /* __u8 iConfiguration; */
  259. 0xc0, /* __u8 bmAttributes;
  260. Bit 7: must be set,
  261. 6: Self-powered,
  262. 5: Remote wakeup,
  263. 4..0: resvd */
  264. 0x00, /* __u8 MaxPower; */
  265. /* one interface */
  266. 0x09, /* __u8 if_bLength; */
  267. 0x04, /* __u8 if_bDescriptorType; Interface */
  268. 0x00, /* __u8 if_bInterfaceNumber; */
  269. 0x00, /* __u8 if_bAlternateSetting; */
  270. 0x01, /* __u8 if_bNumEndpoints; */
  271. 0x09, /* __u8 if_bInterfaceClass; HUB_CLASSCODE */
  272. 0x00, /* __u8 if_bInterfaceSubClass; */
  273. 0x00, /* __u8 if_bInterfaceProtocol; */
  274. 0x00, /* __u8 if_iInterface; */
  275. /* one endpoint (status change endpoint) */
  276. 0x07, /* __u8 ep_bLength; */
  277. 0x05, /* __u8 ep_bDescriptorType; Endpoint */
  278. 0x81, /* __u8 ep_bEndpointAddress; IN Endpoint 1 */
  279. 0x03, /* __u8 ep_bmAttributes; Interrupt */
  280. /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
  281. * see hub.c:hub_configure() for details. */
  282. (USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
  283. 0x0c /* __u8 ep_bInterval; (256ms -- usb 2.0 spec) */
  284. /*
  285. * All 3.0 hubs should have an endpoint companion descriptor,
  286. * but we're ignoring that for now. FIXME?
  287. */
  288. };
  289. /*-------------------------------------------------------------------------*/
  290. /**
  291. * ascii2desc() - Helper routine for producing UTF-16LE string descriptors
  292. * @s: Null-terminated ASCII (actually ISO-8859-1) string
  293. * @buf: Buffer for USB string descriptor (header + UTF-16LE)
  294. * @len: Length (in bytes; may be odd) of descriptor buffer.
  295. *
  296. * The return value is the number of bytes filled in: 2 + 2*strlen(s) or
  297. * buflen, whichever is less.
  298. *
  299. * USB String descriptors can contain at most 126 characters; input
  300. * strings longer than that are truncated.
  301. */
  302. static unsigned
  303. ascii2desc(char const *s, u8 *buf, unsigned len)
  304. {
  305. unsigned n, t = 2 + 2*strlen(s);
  306. if (t > 254)
  307. t = 254; /* Longest possible UTF string descriptor */
  308. if (len > t)
  309. len = t;
  310. t += USB_DT_STRING << 8; /* Now t is first 16 bits to store */
  311. n = len;
  312. while (n--) {
  313. *buf++ = t;
  314. if (!n--)
  315. break;
  316. *buf++ = t >> 8;
  317. t = (unsigned char)*s++;
  318. }
  319. return len;
  320. }
  321. /**
  322. * rh_string() - provides string descriptors for root hub
  323. * @id: the string ID number (0: langids, 1: serial #, 2: product, 3: vendor)
  324. * @hcd: the host controller for this root hub
  325. * @data: buffer for output packet
  326. * @len: length of the provided buffer
  327. *
  328. * Produces either a manufacturer, product or serial number string for the
  329. * virtual root hub device.
  330. * Returns the number of bytes filled in: the length of the descriptor or
  331. * of the provided buffer, whichever is less.
  332. */
  333. static unsigned
  334. rh_string(int id, struct usb_hcd const *hcd, u8 *data, unsigned len)
  335. {
  336. char buf[100];
  337. char const *s;
  338. static char const langids[4] = {4, USB_DT_STRING, 0x09, 0x04};
  339. // language ids
  340. switch (id) {
  341. case 0:
  342. /* Array of LANGID codes (0x0409 is MSFT-speak for "en-us") */
  343. /* See http://www.usb.org/developers/docs/USB_LANGIDs.pdf */
  344. if (len > 4)
  345. len = 4;
  346. memcpy(data, langids, len);
  347. return len;
  348. case 1:
  349. /* Serial number */
  350. s = hcd->self.bus_name;
  351. break;
  352. case 2:
  353. /* Product name */
  354. s = hcd->product_desc;
  355. break;
  356. case 3:
  357. /* Manufacturer */
  358. snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname,
  359. init_utsname()->release, hcd->driver->description);
  360. s = buf;
  361. break;
  362. default:
  363. /* Can't happen; caller guarantees it */
  364. return 0;
  365. }
  366. return ascii2desc(s, data, len);
  367. }
  368. /* Root hub control transfers execute synchronously */
  369. static int rh_call_control (struct usb_hcd *hcd, struct urb *urb)
  370. {
  371. struct usb_ctrlrequest *cmd;
  372. u16 typeReq, wValue, wIndex, wLength;
  373. u8 *ubuf = urb->transfer_buffer;
  374. u8 tbuf [sizeof (struct usb_hub_descriptor)]
  375. __attribute__((aligned(4)));
  376. const u8 *bufp = tbuf;
  377. unsigned len = 0;
  378. int status;
  379. u8 patch_wakeup = 0;
  380. u8 patch_protocol = 0;
  381. might_sleep();
  382. spin_lock_irq(&hcd_root_hub_lock);
  383. status = usb_hcd_link_urb_to_ep(hcd, urb);
  384. spin_unlock_irq(&hcd_root_hub_lock);
  385. if (status)
  386. return status;
  387. urb->hcpriv = hcd; /* Indicate it's queued */
  388. cmd = (struct usb_ctrlrequest *) urb->setup_packet;
  389. typeReq = (cmd->bRequestType << 8) | cmd->bRequest;
  390. wValue = le16_to_cpu (cmd->wValue);
  391. wIndex = le16_to_cpu (cmd->wIndex);
  392. wLength = le16_to_cpu (cmd->wLength);
  393. if (wLength > urb->transfer_buffer_length)
  394. goto error;
  395. urb->actual_length = 0;
  396. switch (typeReq) {
  397. /* DEVICE REQUESTS */
  398. /* The root hub's remote wakeup enable bit is implemented using
  399. * driver model wakeup flags. If this system supports wakeup
  400. * through USB, userspace may change the default "allow wakeup"
  401. * policy through sysfs or these calls.
  402. *
  403. * Most root hubs support wakeup from downstream devices, for
  404. * runtime power management (disabling USB clocks and reducing
  405. * VBUS power usage). However, not all of them do so; silicon,
  406. * board, and BIOS bugs here are not uncommon, so these can't
  407. * be treated quite like external hubs.
  408. *
  409. * Likewise, not all root hubs will pass wakeup events upstream,
  410. * to wake up the whole system. So don't assume root hub and
  411. * controller capabilities are identical.
  412. */
  413. case DeviceRequest | USB_REQ_GET_STATUS:
  414. tbuf [0] = (device_may_wakeup(&hcd->self.root_hub->dev)
  415. << USB_DEVICE_REMOTE_WAKEUP)
  416. | (1 << USB_DEVICE_SELF_POWERED);
  417. tbuf [1] = 0;
  418. len = 2;
  419. break;
  420. case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
  421. if (wValue == USB_DEVICE_REMOTE_WAKEUP)
  422. device_set_wakeup_enable(&hcd->self.root_hub->dev, 0);
  423. else
  424. goto error;
  425. break;
  426. case DeviceOutRequest | USB_REQ_SET_FEATURE:
  427. if (device_can_wakeup(&hcd->self.root_hub->dev)
  428. && wValue == USB_DEVICE_REMOTE_WAKEUP)
  429. device_set_wakeup_enable(&hcd->self.root_hub->dev, 1);
  430. else
  431. goto error;
  432. break;
  433. case DeviceRequest | USB_REQ_GET_CONFIGURATION:
  434. tbuf [0] = 1;
  435. len = 1;
  436. /* FALLTHROUGH */
  437. case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
  438. break;
  439. case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
  440. switch (wValue & 0xff00) {
  441. case USB_DT_DEVICE << 8:
  442. switch (hcd->driver->flags & HCD_MASK) {
  443. case HCD_USB3:
  444. bufp = usb3_rh_dev_descriptor;
  445. break;
  446. case HCD_USB2:
  447. bufp = usb2_rh_dev_descriptor;
  448. break;
  449. case HCD_USB11:
  450. bufp = usb11_rh_dev_descriptor;
  451. break;
  452. default:
  453. goto error;
  454. }
  455. len = 18;
  456. if (hcd->has_tt)
  457. patch_protocol = 1;
  458. break;
  459. case USB_DT_CONFIG << 8:
  460. switch (hcd->driver->flags & HCD_MASK) {
  461. case HCD_USB3:
  462. bufp = ss_rh_config_descriptor;
  463. len = sizeof ss_rh_config_descriptor;
  464. break;
  465. case HCD_USB2:
  466. bufp = hs_rh_config_descriptor;
  467. len = sizeof hs_rh_config_descriptor;
  468. break;
  469. case HCD_USB11:
  470. bufp = fs_rh_config_descriptor;
  471. len = sizeof fs_rh_config_descriptor;
  472. break;
  473. default:
  474. goto error;
  475. }
  476. if (device_can_wakeup(&hcd->self.root_hub->dev))
  477. patch_wakeup = 1;
  478. break;
  479. case USB_DT_STRING << 8:
  480. if ((wValue & 0xff) < 4)
  481. urb->actual_length = rh_string(wValue & 0xff,
  482. hcd, ubuf, wLength);
  483. else /* unsupported IDs --> "protocol stall" */
  484. goto error;
  485. break;
  486. default:
  487. goto error;
  488. }
  489. break;
  490. case DeviceRequest | USB_REQ_GET_INTERFACE:
  491. tbuf [0] = 0;
  492. len = 1;
  493. /* FALLTHROUGH */
  494. case DeviceOutRequest | USB_REQ_SET_INTERFACE:
  495. break;
  496. case DeviceOutRequest | USB_REQ_SET_ADDRESS:
  497. // wValue == urb->dev->devaddr
  498. dev_dbg (hcd->self.controller, "root hub device address %d\n",
  499. wValue);
  500. break;
  501. /* INTERFACE REQUESTS (no defined feature/status flags) */
  502. /* ENDPOINT REQUESTS */
  503. case EndpointRequest | USB_REQ_GET_STATUS:
  504. // ENDPOINT_HALT flag
  505. tbuf [0] = 0;
  506. tbuf [1] = 0;
  507. len = 2;
  508. /* FALLTHROUGH */
  509. case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
  510. case EndpointOutRequest | USB_REQ_SET_FEATURE:
  511. dev_dbg (hcd->self.controller, "no endpoint features yet\n");
  512. break;
  513. /* CLASS REQUESTS (and errors) */
  514. default:
  515. /* non-generic request */
  516. switch (typeReq) {
  517. case GetHubStatus:
  518. case GetPortStatus:
  519. len = 4;
  520. break;
  521. case GetHubDescriptor:
  522. len = sizeof (struct usb_hub_descriptor);
  523. break;
  524. }
  525. status = hcd->driver->hub_control (hcd,
  526. typeReq, wValue, wIndex,
  527. tbuf, wLength);
  528. break;
  529. error:
  530. /* "protocol stall" on error */
  531. status = -EPIPE;
  532. }
  533. if (status) {
  534. len = 0;
  535. if (status != -EPIPE) {
  536. dev_dbg (hcd->self.controller,
  537. "CTRL: TypeReq=0x%x val=0x%x "
  538. "idx=0x%x len=%d ==> %d\n",
  539. typeReq, wValue, wIndex,
  540. wLength, status);
  541. }
  542. }
  543. if (len) {
  544. if (urb->transfer_buffer_length < len)
  545. len = urb->transfer_buffer_length;
  546. urb->actual_length = len;
  547. // always USB_DIR_IN, toward host
  548. memcpy (ubuf, bufp, len);
  549. /* report whether RH hardware supports remote wakeup */
  550. if (patch_wakeup &&
  551. len > offsetof (struct usb_config_descriptor,
  552. bmAttributes))
  553. ((struct usb_config_descriptor *)ubuf)->bmAttributes
  554. |= USB_CONFIG_ATT_WAKEUP;
  555. /* report whether RH hardware has an integrated TT */
  556. if (patch_protocol &&
  557. len > offsetof(struct usb_device_descriptor,
  558. bDeviceProtocol))
  559. ((struct usb_device_descriptor *) ubuf)->
  560. bDeviceProtocol = 1;
  561. }
  562. /* any errors get returned through the urb completion */
  563. spin_lock_irq(&hcd_root_hub_lock);
  564. usb_hcd_unlink_urb_from_ep(hcd, urb);
  565. /* This peculiar use of spinlocks echoes what real HC drivers do.
  566. * Avoiding calls to local_irq_disable/enable makes the code
  567. * RT-friendly.
  568. */
  569. spin_unlock(&hcd_root_hub_lock);
  570. usb_hcd_giveback_urb(hcd, urb, status);
  571. spin_lock(&hcd_root_hub_lock);
  572. spin_unlock_irq(&hcd_root_hub_lock);
  573. return 0;
  574. }
  575. /*-------------------------------------------------------------------------*/
  576. /*
  577. * Root Hub interrupt transfers are polled using a timer if the
  578. * driver requests it; otherwise the driver is responsible for
  579. * calling usb_hcd_poll_rh_status() when an event occurs.
  580. *
  581. * Completions are called in_interrupt(), but they may or may not
  582. * be in_irq().
  583. */
  584. void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
  585. {
  586. struct urb *urb;
  587. int length;
  588. unsigned long flags;
  589. char buffer[6]; /* Any root hubs with > 31 ports? */
  590. if (unlikely(!hcd->rh_registered))
  591. return;
  592. if (!hcd->uses_new_polling && !hcd->status_urb)
  593. return;
  594. length = hcd->driver->hub_status_data(hcd, buffer);
  595. if (length > 0) {
  596. /* try to complete the status urb */
  597. spin_lock_irqsave(&hcd_root_hub_lock, flags);
  598. urb = hcd->status_urb;
  599. if (urb) {
  600. hcd->poll_pending = 0;
  601. hcd->status_urb = NULL;
  602. urb->actual_length = length;
  603. memcpy(urb->transfer_buffer, buffer, length);
  604. usb_hcd_unlink_urb_from_ep(hcd, urb);
  605. spin_unlock(&hcd_root_hub_lock);
  606. usb_hcd_giveback_urb(hcd, urb, 0);
  607. spin_lock(&hcd_root_hub_lock);
  608. } else {
  609. length = 0;
  610. hcd->poll_pending = 1;
  611. }
  612. spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
  613. }
  614. /* The USB 2.0 spec says 256 ms. This is close enough and won't
  615. * exceed that limit if HZ is 100. The math is more clunky than
  616. * maybe expected, this is to make sure that all timers for USB devices
  617. * fire at the same time to give the CPU a break inbetween */
  618. if (hcd->uses_new_polling ? hcd->poll_rh :
  619. (length == 0 && hcd->status_urb != NULL))
  620. mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
  621. }
  622. EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status);
  623. /* timer callback */
  624. static void rh_timer_func (unsigned long _hcd)
  625. {
  626. usb_hcd_poll_rh_status((struct usb_hcd *) _hcd);
  627. }
  628. /*-------------------------------------------------------------------------*/
  629. static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb)
  630. {
  631. int retval;
  632. unsigned long flags;
  633. unsigned len = 1 + (urb->dev->maxchild / 8);
  634. spin_lock_irqsave (&hcd_root_hub_lock, flags);
  635. if (hcd->status_urb || urb->transfer_buffer_length < len) {
  636. dev_dbg (hcd->self.controller, "not queuing rh status urb\n");
  637. retval = -EINVAL;
  638. goto done;
  639. }
  640. retval = usb_hcd_link_urb_to_ep(hcd, urb);
  641. if (retval)
  642. goto done;
  643. hcd->status_urb = urb;
  644. urb->hcpriv = hcd; /* indicate it's queued */
  645. if (!hcd->uses_new_polling)
  646. mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
  647. /* If a status change has already occurred, report it ASAP */
  648. else if (hcd->poll_pending)
  649. mod_timer(&hcd->rh_timer, jiffies);
  650. retval = 0;
  651. done:
  652. spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
  653. return retval;
  654. }
  655. static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb)
  656. {
  657. if (usb_endpoint_xfer_int(&urb->ep->desc))
  658. return rh_queue_status (hcd, urb);
  659. if (usb_endpoint_xfer_control(&urb->ep->desc))
  660. return rh_call_control (hcd, urb);
  661. return -EINVAL;
  662. }
  663. /*-------------------------------------------------------------------------*/
  664. /* Unlinks of root-hub control URBs are legal, but they don't do anything
  665. * since these URBs always execute synchronously.
  666. */
  667. static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
  668. {
  669. unsigned long flags;
  670. int rc;
  671. spin_lock_irqsave(&hcd_root_hub_lock, flags);
  672. rc = usb_hcd_check_unlink_urb(hcd, urb, status);
  673. if (rc)
  674. goto done;
  675. if (usb_endpoint_num(&urb->ep->desc) == 0) { /* Control URB */
  676. ; /* Do nothing */
  677. } else { /* Status URB */
  678. if (!hcd->uses_new_polling)
  679. del_timer (&hcd->rh_timer);
  680. if (urb == hcd->status_urb) {
  681. hcd->status_urb = NULL;
  682. usb_hcd_unlink_urb_from_ep(hcd, urb);
  683. spin_unlock(&hcd_root_hub_lock);
  684. usb_hcd_giveback_urb(hcd, urb, status);
  685. spin_lock(&hcd_root_hub_lock);
  686. }
  687. }
  688. done:
  689. spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
  690. return rc;
  691. }
  692. /*
  693. * Show & store the current value of authorized_default
  694. */
  695. static ssize_t usb_host_authorized_default_show(struct device *dev,
  696. struct device_attribute *attr,
  697. char *buf)
  698. {
  699. struct usb_device *rh_usb_dev = to_usb_device(dev);
  700. struct usb_bus *usb_bus = rh_usb_dev->bus;
  701. struct usb_hcd *usb_hcd;
  702. if (usb_bus == NULL) /* FIXME: not sure if this case is possible */
  703. return -ENODEV;
  704. usb_hcd = bus_to_hcd(usb_bus);
  705. return snprintf(buf, PAGE_SIZE, "%u\n", usb_hcd->authorized_default);
  706. }
  707. static ssize_t usb_host_authorized_default_store(struct device *dev,
  708. struct device_attribute *attr,
  709. const char *buf, size_t size)
  710. {
  711. ssize_t result;
  712. unsigned val;
  713. struct usb_device *rh_usb_dev = to_usb_device(dev);
  714. struct usb_bus *usb_bus = rh_usb_dev->bus;
  715. struct usb_hcd *usb_hcd;
  716. if (usb_bus == NULL) /* FIXME: not sure if this case is possible */
  717. return -ENODEV;
  718. usb_hcd = bus_to_hcd(usb_bus);
  719. result = sscanf(buf, "%u\n", &val);
  720. if (result == 1) {
  721. usb_hcd->authorized_default = val? 1 : 0;
  722. result = size;
  723. }
  724. else
  725. result = -EINVAL;
  726. return result;
  727. }
  728. static DEVICE_ATTR(authorized_default, 0644,
  729. usb_host_authorized_default_show,
  730. usb_host_authorized_default_store);
  731. /* Group all the USB bus attributes */
  732. static struct attribute *usb_bus_attrs[] = {
  733. &dev_attr_authorized_default.attr,
  734. NULL,
  735. };
  736. static struct attribute_group usb_bus_attr_group = {
  737. .name = NULL, /* we want them in the same directory */
  738. .attrs = usb_bus_attrs,
  739. };
  740. /*-------------------------------------------------------------------------*/
  741. /**
  742. * usb_bus_init - shared initialization code
  743. * @bus: the bus structure being initialized
  744. *
  745. * This code is used to initialize a usb_bus structure, memory for which is
  746. * separately managed.
  747. */
  748. static void usb_bus_init (struct usb_bus *bus)
  749. {
  750. memset (&bus->devmap, 0, sizeof(struct usb_devmap));
  751. bus->devnum_next = 1;
  752. bus->root_hub = NULL;
  753. bus->busnum = -1;
  754. bus->bandwidth_allocated = 0;
  755. bus->bandwidth_int_reqs = 0;
  756. bus->bandwidth_isoc_reqs = 0;
  757. INIT_LIST_HEAD (&bus->bus_list);
  758. }
  759. /*-------------------------------------------------------------------------*/
  760. /**
  761. * usb_register_bus - registers the USB host controller with the usb core
  762. * @bus: pointer to the bus to register
  763. * Context: !in_interrupt()
  764. *
  765. * Assigns a bus number, and links the controller into usbcore data
  766. * structures so that it can be seen by scanning the bus list.
  767. */
  768. static int usb_register_bus(struct usb_bus *bus)
  769. {
  770. int result = -E2BIG;
  771. int busnum;
  772. mutex_lock(&usb_bus_list_lock);
  773. busnum = find_next_zero_bit (busmap.busmap, USB_MAXBUS, 1);
  774. if (busnum >= USB_MAXBUS) {
  775. printk (KERN_ERR "%s: too many buses\n", usbcore_name);
  776. goto error_find_busnum;
  777. }
  778. set_bit (busnum, busmap.busmap);
  779. bus->busnum = busnum;
  780. /* Add it to the local list of buses */
  781. list_add (&bus->bus_list, &usb_bus_list);
  782. mutex_unlock(&usb_bus_list_lock);
  783. usb_notify_add_bus(bus);
  784. dev_info (bus->controller, "new USB bus registered, assigned bus "
  785. "number %d\n", bus->busnum);
  786. return 0;
  787. error_find_busnum:
  788. mutex_unlock(&usb_bus_list_lock);
  789. return result;
  790. }
  791. /**
  792. * usb_deregister_bus - deregisters the USB host controller
  793. * @bus: pointer to the bus to deregister
  794. * Context: !in_interrupt()
  795. *
  796. * Recycles the bus number, and unlinks the controller from usbcore data
  797. * structures so that it won't be seen by scanning the bus list.
  798. */
  799. static void usb_deregister_bus (struct usb_bus *bus)
  800. {
  801. dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum);
  802. /*
  803. * NOTE: make sure that all the devices are removed by the
  804. * controller code, as well as having it call this when cleaning
  805. * itself up
  806. */
  807. mutex_lock(&usb_bus_list_lock);
  808. list_del (&bus->bus_list);
  809. mutex_unlock(&usb_bus_list_lock);
  810. usb_notify_remove_bus(bus);
  811. clear_bit (bus->busnum, busmap.busmap);
  812. }
  813. /**
  814. * register_root_hub - called by usb_add_hcd() to register a root hub
  815. * @hcd: host controller for this root hub
  816. *
  817. * This function registers the root hub with the USB subsystem. It sets up
  818. * the device properly in the device tree and then calls usb_new_device()
  819. * to register the usb device. It also assigns the root hub's USB address
  820. * (always 1).
  821. */
  822. static int register_root_hub(struct usb_hcd *hcd)
  823. {
  824. struct device *parent_dev = hcd->self.controller;
  825. struct usb_device *usb_dev = hcd->self.root_hub;
  826. const int devnum = 1;
  827. int retval;
  828. usb_dev->devnum = devnum;
  829. usb_dev->bus->devnum_next = devnum + 1;
  830. memset (&usb_dev->bus->devmap.devicemap, 0,
  831. sizeof usb_dev->bus->devmap.devicemap);
  832. set_bit (devnum, usb_dev->bus->devmap.devicemap);
  833. usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
  834. mutex_lock(&usb_bus_list_lock);
  835. usb_dev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
  836. retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE);
  837. if (retval != sizeof usb_dev->descriptor) {
  838. mutex_unlock(&usb_bus_list_lock);
  839. dev_dbg (parent_dev, "can't read %s device descriptor %d\n",
  840. dev_name(&usb_dev->dev), retval);
  841. return (retval < 0) ? retval : -EMSGSIZE;
  842. }
  843. retval = usb_new_device (usb_dev);
  844. if (retval) {
  845. dev_err (parent_dev, "can't register root hub for %s, %d\n",
  846. dev_name(&usb_dev->dev), retval);
  847. }
  848. mutex_unlock(&usb_bus_list_lock);
  849. if (retval == 0) {
  850. spin_lock_irq (&hcd_root_hub_lock);
  851. hcd->rh_registered = 1;
  852. spin_unlock_irq (&hcd_root_hub_lock);
  853. /* Did the HC die before the root hub was registered? */
  854. if (hcd->state == HC_STATE_HALT)
  855. usb_hc_died (hcd); /* This time clean up */
  856. }
  857. return retval;
  858. }
  859. /*-------------------------------------------------------------------------*/
  860. /**
  861. * usb_calc_bus_time - approximate periodic transaction time in nanoseconds
  862. * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH}
  863. * @is_input: true iff the transaction sends data to the host
  864. * @isoc: true for isochronous transactions, false for interrupt ones
  865. * @bytecount: how many bytes in the transaction.
  866. *
  867. * Returns approximate bus time in nanoseconds for a periodic transaction.
  868. * See USB 2.0 spec section 5.11.3; only periodic transfers need to be
  869. * scheduled in software, this function is only used for such scheduling.
  870. */
  871. long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount)
  872. {
  873. unsigned long tmp;
  874. switch (speed) {
  875. case USB_SPEED_LOW: /* INTR only */
  876. if (is_input) {
  877. tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L;
  878. return (64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp);
  879. } else {
  880. tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L;
  881. return (64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp);
  882. }
  883. case USB_SPEED_FULL: /* ISOC or INTR */
  884. if (isoc) {
  885. tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
  886. return (((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp);
  887. } else {
  888. tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
  889. return (9107L + BW_HOST_DELAY + tmp);
  890. }
  891. case USB_SPEED_HIGH: /* ISOC or INTR */
  892. // FIXME adjust for input vs output
  893. if (isoc)
  894. tmp = HS_NSECS_ISO (bytecount);
  895. else
  896. tmp = HS_NSECS (bytecount);
  897. return tmp;
  898. default:
  899. pr_debug ("%s: bogus device speed!\n", usbcore_name);
  900. return -1;
  901. }
  902. }
  903. EXPORT_SYMBOL_GPL(usb_calc_bus_time);
  904. /*-------------------------------------------------------------------------*/
  905. /*
  906. * Generic HC operations.
  907. */
  908. /*-------------------------------------------------------------------------*/
  909. /**
  910. * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue
  911. * @hcd: host controller to which @urb was submitted
  912. * @urb: URB being submitted
  913. *
  914. * Host controller drivers should call this routine in their enqueue()
  915. * method. The HCD's private spinlock must be held and interrupts must
  916. * be disabled. The actions carried out here are required for URB
  917. * submission, as well as for endpoint shutdown and for usb_kill_urb.
  918. *
  919. * Returns 0 for no error, otherwise a negative error code (in which case
  920. * the enqueue() method must fail). If no error occurs but enqueue() fails
  921. * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing
  922. * the private spinlock and returning.
  923. */
  924. int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb)
  925. {
  926. int rc = 0;
  927. spin_lock(&hcd_urb_list_lock);
  928. /* Check that the URB isn't being killed */
  929. if (unlikely(atomic_read(&urb->reject))) {
  930. rc = -EPERM;
  931. goto done;
  932. }
  933. if (unlikely(!urb->ep->enabled)) {
  934. rc = -ENOENT;
  935. goto done;
  936. }
  937. if (unlikely(!urb->dev->can_submit)) {
  938. rc = -EHOSTUNREACH;
  939. goto done;
  940. }
  941. /*
  942. * Check the host controller's state and add the URB to the
  943. * endpoint's queue.
  944. */
  945. switch (hcd->state) {
  946. case HC_STATE_RUNNING:
  947. case HC_STATE_RESUMING:
  948. urb->unlinked = 0;
  949. list_add_tail(&urb->urb_list, &urb->ep->urb_list);
  950. break;
  951. default:
  952. rc = -ESHUTDOWN;
  953. goto done;
  954. }
  955. done:
  956. spin_unlock(&hcd_urb_list_lock);
  957. return rc;
  958. }
  959. EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep);
  960. /**
  961. * usb_hcd_check_unlink_urb - check whether an URB may be unlinked
  962. * @hcd: host controller to which @urb was submitted
  963. * @urb: URB being checked for unlinkability
  964. * @status: error code to store in @urb if the unlink succeeds
  965. *
  966. * Host controller drivers should call this routine in their dequeue()
  967. * method. The HCD's private spinlock must be held and interrupts must
  968. * be disabled. The actions carried out here are required for making
  969. * sure than an unlink is valid.
  970. *
  971. * Returns 0 for no error, otherwise a negative error code (in which case
  972. * the dequeue() method must fail). The possible error codes are:
  973. *
  974. * -EIDRM: @urb was not submitted or has already completed.
  975. * The completion function may not have been called yet.
  976. *
  977. * -EBUSY: @urb has already been unlinked.
  978. */
  979. int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb,
  980. int status)
  981. {
  982. struct list_head *tmp;
  983. /* insist the urb is still queued */
  984. list_for_each(tmp, &urb->ep->urb_list) {
  985. if (tmp == &urb->urb_list)
  986. break;
  987. }
  988. if (tmp != &urb->urb_list)
  989. return -EIDRM;
  990. /* Any status except -EINPROGRESS means something already started to
  991. * unlink this URB from the hardware. So there's no more work to do.
  992. */
  993. if (urb->unlinked)
  994. return -EBUSY;
  995. urb->unlinked = status;
  996. /* IRQ setup can easily be broken so that USB controllers
  997. * never get completion IRQs ... maybe even the ones we need to
  998. * finish unlinking the initial failed usb_set_address()
  999. * or device descriptor fetch.
  1000. */
  1001. if (!test_bit(HCD_FLAG_SAW_IRQ, &hcd->flags) &&
  1002. !is_root_hub(urb->dev)) {
  1003. dev_warn(hcd->self.controller, "Unlink after no-IRQ? "
  1004. "Controller is probably using the wrong IRQ.\n");
  1005. set_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);
  1006. }
  1007. return 0;
  1008. }
  1009. EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb);
  1010. /**
  1011. * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue
  1012. * @hcd: host controller to which @urb was submitted
  1013. * @urb: URB being unlinked
  1014. *
  1015. * Host controller drivers should call this routine before calling
  1016. * usb_hcd_giveback_urb(). The HCD's private spinlock must be held and
  1017. * interrupts must be disabled. The actions carried out here are required
  1018. * for URB completion.
  1019. */
  1020. void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb)
  1021. {
  1022. /* clear all state linking urb to this dev (and hcd) */
  1023. spin_lock(&hcd_urb_list_lock);
  1024. list_del_init(&urb->urb_list);
  1025. spin_unlock(&hcd_urb_list_lock);
  1026. }
  1027. EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep);
  1028. /*
  1029. * Some usb host controllers can only perform dma using a small SRAM area.
  1030. * The usb core itself is however optimized for host controllers that can dma
  1031. * using regular system memory - like pci devices doing bus mastering.
  1032. *
  1033. * To support host controllers with limited dma capabilites we provide dma
  1034. * bounce buffers. This feature can be enabled using the HCD_LOCAL_MEM flag.
  1035. * For this to work properly the host controller code must first use the
  1036. * function dma_declare_coherent_memory() to point out which memory area
  1037. * that should be used for dma allocations.
  1038. *
  1039. * The HCD_LOCAL_MEM flag then tells the usb code to allocate all data for
  1040. * dma using dma_alloc_coherent() which in turn allocates from the memory
  1041. * area pointed out with dma_declare_coherent_memory().
  1042. *
  1043. * So, to summarize...
  1044. *
  1045. * - We need "local" memory, canonical example being
  1046. * a small SRAM on a discrete controller being the
  1047. * only memory that the controller can read ...
  1048. * (a) "normal" kernel memory is no good, and
  1049. * (b) there's not enough to share
  1050. *
  1051. * - The only *portable* hook for such stuff in the
  1052. * DMA framework is dma_declare_coherent_memory()
  1053. *
  1054. * - So we use that, even though the primary requirement
  1055. * is that the memory be "local" (hence addressible
  1056. * by that device), not "coherent".
  1057. *
  1058. */
  1059. static int hcd_alloc_coherent(struct usb_bus *bus,
  1060. gfp_t mem_flags, dma_addr_t *dma_handle,
  1061. void **vaddr_handle, size_t size,
  1062. enum dma_data_direction dir)
  1063. {
  1064. unsigned char *vaddr;
  1065. vaddr = hcd_buffer_alloc(bus, size + sizeof(vaddr),
  1066. mem_flags, dma_handle);
  1067. if (!vaddr)
  1068. return -ENOMEM;
  1069. /*
  1070. * Store the virtual address of the buffer at the end
  1071. * of the allocated dma buffer. The size of the buffer
  1072. * may be uneven so use unaligned functions instead
  1073. * of just rounding up. It makes sense to optimize for
  1074. * memory footprint over access speed since the amount
  1075. * of memory available for dma may be limited.
  1076. */
  1077. put_unaligned((unsigned long)*vaddr_handle,
  1078. (unsigned long *)(vaddr + size));
  1079. if (dir == DMA_TO_DEVICE)
  1080. memcpy(vaddr, *vaddr_handle, size);
  1081. *vaddr_handle = vaddr;
  1082. return 0;
  1083. }
  1084. static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle,
  1085. void **vaddr_handle, size_t size,
  1086. enum dma_data_direction dir)
  1087. {
  1088. unsigned char *vaddr = *vaddr_handle;
  1089. vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size));
  1090. if (dir == DMA_FROM_DEVICE)
  1091. memcpy(vaddr, *vaddr_handle, size);
  1092. hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle);
  1093. *vaddr_handle = vaddr;
  1094. *dma_handle = 0;
  1095. }
  1096. static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
  1097. gfp_t mem_flags)
  1098. {
  1099. enum dma_data_direction dir;
  1100. int ret = 0;
  1101. /* Map the URB's buffers for DMA access.
  1102. * Lower level HCD code should use *_dma exclusively,
  1103. * unless it uses pio or talks to another transport,
  1104. * or uses the provided scatter gather list for bulk.
  1105. */
  1106. if (is_root_hub(urb->dev))
  1107. return 0;
  1108. if (usb_endpoint_xfer_control(&urb->ep->desc)
  1109. && !(urb->transfer_flags & URB_NO_SETUP_DMA_MAP)) {
  1110. if (hcd->self.uses_dma) {
  1111. urb->setup_dma = dma_map_single(
  1112. hcd->self.controller,
  1113. urb->setup_packet,
  1114. sizeof(struct usb_ctrlrequest),
  1115. DMA_TO_DEVICE);
  1116. if (dma_mapping_error(hcd->self.controller,
  1117. urb->setup_dma))
  1118. return -EAGAIN;
  1119. } else if (hcd->driver->flags & HCD_LOCAL_MEM)
  1120. ret = hcd_alloc_coherent(
  1121. urb->dev->bus, mem_flags,
  1122. &urb->setup_dma,
  1123. (void **)&urb->setup_packet,
  1124. sizeof(struct usb_ctrlrequest),
  1125. DMA_TO_DEVICE);
  1126. }
  1127. dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
  1128. if (ret == 0 && urb->transfer_buffer_length != 0
  1129. && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
  1130. if (hcd->self.uses_dma) {
  1131. urb->transfer_dma = dma_map_single (
  1132. hcd->self.controller,
  1133. urb->transfer_buffer,
  1134. urb->transfer_buffer_length,
  1135. dir);
  1136. if (dma_mapping_error(hcd->self.controller,
  1137. urb->transfer_dma))
  1138. return -EAGAIN;
  1139. } else if (hcd->driver->flags & HCD_LOCAL_MEM) {
  1140. ret = hcd_alloc_coherent(
  1141. urb->dev->bus, mem_flags,
  1142. &urb->transfer_dma,
  1143. &urb->transfer_buffer,
  1144. urb->transfer_buffer_length,
  1145. dir);
  1146. if (ret && usb_endpoint_xfer_control(&urb->ep->desc)
  1147. && !(urb->transfer_flags & URB_NO_SETUP_DMA_MAP))
  1148. hcd_free_coherent(urb->dev->bus,
  1149. &urb->setup_dma,
  1150. (void **)&urb->setup_packet,
  1151. sizeof(struct usb_ctrlrequest),
  1152. DMA_TO_DEVICE);
  1153. }
  1154. }
  1155. return ret;
  1156. }
  1157. static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
  1158. {
  1159. enum dma_data_direction dir;
  1160. if (is_root_hub(urb->dev))
  1161. return;
  1162. if (usb_endpoint_xfer_control(&urb->ep->desc)
  1163. && !(urb->transfer_flags & URB_NO_SETUP_DMA_MAP)) {
  1164. if (hcd->self.uses_dma)
  1165. dma_unmap_single(hcd->self.controller, urb->setup_dma,
  1166. sizeof(struct usb_ctrlrequest),
  1167. DMA_TO_DEVICE);
  1168. else if (hcd->driver->flags & HCD_LOCAL_MEM)
  1169. hcd_free_coherent(urb->dev->bus, &urb->setup_dma,
  1170. (void **)&urb->setup_packet,
  1171. sizeof(struct usb_ctrlrequest),
  1172. DMA_TO_DEVICE);
  1173. }
  1174. dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
  1175. if (urb->transfer_buffer_length != 0
  1176. && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
  1177. if (hcd->self.uses_dma)
  1178. dma_unmap_single(hcd->self.controller,
  1179. urb->transfer_dma,
  1180. urb->transfer_buffer_length,
  1181. dir);
  1182. else if (hcd->driver->flags & HCD_LOCAL_MEM)
  1183. hcd_free_coherent(urb->dev->bus, &urb->transfer_dma,
  1184. &urb->transfer_buffer,
  1185. urb->transfer_buffer_length,
  1186. dir);
  1187. }
  1188. }
  1189. /*-------------------------------------------------------------------------*/
  1190. /* may be called in any context with a valid urb->dev usecount
  1191. * caller surrenders "ownership" of urb
  1192. * expects usb_submit_urb() to have sanity checked and conditioned all
  1193. * inputs in the urb
  1194. */
  1195. int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
  1196. {
  1197. int status;
  1198. struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus);
  1199. /* increment urb's reference count as part of giving it to the HCD
  1200. * (which will control it). HCD guarantees that it either returns
  1201. * an error or calls giveback(), but not both.
  1202. */
  1203. usb_get_urb(urb);
  1204. atomic_inc(&urb->use_count);
  1205. atomic_inc(&urb->dev->urbnum);
  1206. usbmon_urb_submit(&hcd->self, urb);
  1207. /* NOTE requirements on root-hub callers (usbfs and the hub
  1208. * driver, for now): URBs' urb->transfer_buffer must be
  1209. * valid and usb_buffer_{sync,unmap}() not be needed, since
  1210. * they could clobber root hub response data. Also, control
  1211. * URBs must be submitted in process context with interrupts
  1212. * enabled.
  1213. */
  1214. status = map_urb_for_dma(hcd, urb, mem_flags);
  1215. if (unlikely(status)) {
  1216. usbmon_urb_submit_error(&hcd->self, urb, status);
  1217. goto error;
  1218. }
  1219. if (is_root_hub(urb->dev))
  1220. status = rh_urb_enqueue(hcd, urb);
  1221. else
  1222. status = hcd->driver->urb_enqueue(hcd, urb, mem_flags);
  1223. if (unlikely(status)) {
  1224. usbmon_urb_submit_error(&hcd->self, urb, status);
  1225. unmap_urb_for_dma(hcd, urb);
  1226. error:
  1227. urb->hcpriv = NULL;
  1228. INIT_LIST_HEAD(&urb->urb_list);
  1229. atomic_dec(&urb->use_count);
  1230. atomic_dec(&urb->dev->urbnum);
  1231. if (atomic_read(&urb->reject))
  1232. wake_up(&usb_kill_urb_queue);
  1233. usb_put_urb(urb);
  1234. }
  1235. return status;
  1236. }
  1237. /*-------------------------------------------------------------------------*/
  1238. /* this makes the hcd giveback() the urb more quickly, by kicking it
  1239. * off hardware queues (which may take a while) and returning it as
  1240. * soon as practical. we've already set up the urb's return status,
  1241. * but we can't know if the callback completed already.
  1242. */
  1243. static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status)
  1244. {
  1245. int value;
  1246. if (is_root_hub(urb->dev))
  1247. value = usb_rh_urb_dequeue(hcd, urb, status);
  1248. else {
  1249. /* The only reason an HCD might fail this call is if
  1250. * it has not yet fully queued the urb to begin with.
  1251. * Such failures should be harmless. */
  1252. value = hcd->driver->urb_dequeue(hcd, urb, status);
  1253. }
  1254. return value;
  1255. }
  1256. /*
  1257. * called in any context
  1258. *
  1259. * caller guarantees urb won't be recycled till both unlink()
  1260. * and the urb's completion function return
  1261. */
  1262. int usb_hcd_unlink_urb (struct urb *urb, int status)
  1263. {
  1264. struct usb_hcd *hcd;
  1265. int retval = -EIDRM;
  1266. unsigned long flags;
  1267. /* Prevent the device and bus from going away while
  1268. * the unlink is carried out. If they are already gone
  1269. * then urb->use_count must be 0, since disconnected
  1270. * devices can't have any active URBs.
  1271. */
  1272. spin_lock_irqsave(&hcd_urb_unlink_lock, flags);
  1273. if (atomic_read(&urb->use_count) > 0) {
  1274. retval = 0;
  1275. usb_get_dev(urb->dev);
  1276. }
  1277. spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags);
  1278. if (retval == 0) {
  1279. hcd = bus_to_hcd(urb->dev->bus);
  1280. retval = unlink1(hcd, urb, status);
  1281. usb_put_dev(urb->dev);
  1282. }
  1283. if (retval == 0)
  1284. retval = -EINPROGRESS;
  1285. else if (retval != -EIDRM && retval != -EBUSY)
  1286. dev_dbg(&urb->dev->dev, "hcd_unlink_urb %p fail %d\n",
  1287. urb, retval);
  1288. return retval;
  1289. }
  1290. /*-------------------------------------------------------------------------*/
  1291. /**
  1292. * usb_hcd_giveback_urb - return URB from HCD to device driver
  1293. * @hcd: host controller returning the URB
  1294. * @urb: urb being returned to the USB device driver.
  1295. * @status: completion status code for the URB.
  1296. * Context: in_interrupt()
  1297. *
  1298. * This hands the URB from HCD to its USB device driver, using its
  1299. * completion function. The HCD has freed all per-urb resources
  1300. * (and is done using urb->hcpriv). It also released all HCD locks;
  1301. * the device driver won't cause problems if it frees, modifies,
  1302. * or resubmits this URB.
  1303. *
  1304. * If @urb was unlinked, the value of @status will be overridden by
  1305. * @urb->unlinked. Erroneous short transfers are detected in case
  1306. * the HCD hasn't checked for them.
  1307. */
  1308. void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
  1309. {
  1310. urb->hcpriv = NULL;
  1311. if (unlikely(urb->unlinked))
  1312. status = urb->unlinked;
  1313. else if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
  1314. urb->actual_length < urb->transfer_buffer_length &&
  1315. !status))
  1316. status = -EREMOTEIO;
  1317. unmap_urb_for_dma(hcd, urb);
  1318. usbmon_urb_complete(&hcd->self, urb, status);
  1319. usb_unanchor_urb(urb);
  1320. /* pass ownership to the completion handler */
  1321. urb->status = status;
  1322. urb->complete (urb);
  1323. atomic_dec (&urb->use_count);
  1324. if (unlikely(atomic_read(&urb->reject)))
  1325. wake_up (&usb_kill_urb_queue);
  1326. usb_put_urb (urb);
  1327. }
  1328. EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb);
  1329. /*-------------------------------------------------------------------------*/
  1330. /* Cancel all URBs pending on this endpoint and wait for the endpoint's
  1331. * queue to drain completely. The caller must first insure that no more
  1332. * URBs can be submitted for this endpoint.
  1333. */
  1334. void usb_hcd_flush_endpoint(struct usb_device *udev,
  1335. struct usb_host_endpoint *ep)
  1336. {
  1337. struct usb_hcd *hcd;
  1338. struct urb *urb;
  1339. if (!ep)
  1340. return;
  1341. might_sleep();
  1342. hcd = bus_to_hcd(udev->bus);
  1343. /* No more submits can occur */
  1344. spin_lock_irq(&hcd_urb_list_lock);
  1345. rescan:
  1346. list_for_each_entry (urb, &ep->urb_list, urb_list) {
  1347. int is_in;
  1348. if (urb->unlinked)
  1349. continue;
  1350. usb_get_urb (urb);
  1351. is_in = usb_urb_dir_in(urb);
  1352. spin_unlock(&hcd_urb_list_lock);
  1353. /* kick hcd */
  1354. unlink1(hcd, urb, -ESHUTDOWN);
  1355. dev_dbg (hcd->self.controller,
  1356. "shutdown urb %p ep%d%s%s\n",
  1357. urb, usb_endpoint_num(&ep->desc),
  1358. is_in ? "in" : "out",
  1359. ({ char *s;
  1360. switch (usb_endpoint_type(&ep->desc)) {
  1361. case USB_ENDPOINT_XFER_CONTROL:
  1362. s = ""; break;
  1363. case USB_ENDPOINT_XFER_BULK:
  1364. s = "-bulk"; break;
  1365. case USB_ENDPOINT_XFER_INT:
  1366. s = "-intr"; break;
  1367. default:
  1368. s = "-iso"; break;
  1369. };
  1370. s;
  1371. }));
  1372. usb_put_urb (urb);
  1373. /* list contents may have changed */
  1374. spin_lock(&hcd_urb_list_lock);
  1375. goto rescan;
  1376. }
  1377. spin_unlock_irq(&hcd_urb_list_lock);
  1378. /* Wait until the endpoint queue is completely empty */
  1379. while (!list_empty (&ep->urb_list)) {
  1380. spin_lock_irq(&hcd_urb_list_lock);
  1381. /* The list may have changed while we acquired the spinlock */
  1382. urb = NULL;
  1383. if (!list_empty (&ep->urb_list)) {
  1384. urb = list_entry (ep->urb_list.prev, struct urb,
  1385. urb_list);
  1386. usb_get_urb (urb);
  1387. }
  1388. spin_unlock_irq(&hcd_urb_list_lock);
  1389. if (urb) {
  1390. usb_kill_urb (urb);
  1391. usb_put_urb (urb);
  1392. }
  1393. }
  1394. }
  1395. /**
  1396. * Check whether a new bandwidth setting exceeds the bus bandwidth.
  1397. * @new_config: new configuration to install
  1398. * @cur_alt: the current alternate interface setting
  1399. * @new_alt: alternate interface setting that is being installed
  1400. *
  1401. * To change configurations, pass in the new configuration in new_config,
  1402. * and pass NULL for cur_alt and new_alt.
  1403. *
  1404. * To reset a device's configuration (put the device in the ADDRESSED state),
  1405. * pass in NULL for new_config, cur_alt, and new_alt.
  1406. *
  1407. * To change alternate interface settings, pass in NULL for new_config,
  1408. * pass in the current alternate interface setting in cur_alt,
  1409. * and pass in the new alternate interface setting in new_alt.
  1410. *
  1411. * Returns an error if the requested bandwidth change exceeds the
  1412. * bus bandwidth or host controller internal resources.
  1413. */
  1414. int usb_hcd_alloc_bandwidth(struct usb_device *udev,
  1415. struct usb_host_config *new_config,
  1416. struct usb_host_interface *cur_alt,
  1417. struct usb_host_interface *new_alt)
  1418. {
  1419. int num_intfs, i, j;
  1420. struct usb_host_interface *alt = NULL;
  1421. int ret = 0;
  1422. struct usb_hcd *hcd;
  1423. struct usb_host_endpoint *ep;
  1424. hcd = bus_to_hcd(udev->bus);
  1425. if (!hcd->driver->check_bandwidth)
  1426. return 0;
  1427. /* Configuration is being removed - set configuration 0 */
  1428. if (!new_config && !cur_alt) {
  1429. for (i = 1; i < 16; ++i) {
  1430. ep = udev->ep_out[i];
  1431. if (ep)
  1432. hcd->driver->drop_endpoint(hcd, udev, ep);
  1433. ep = udev->ep_in[i];
  1434. if (ep)
  1435. hcd->driver->drop_endpoint(hcd, udev, ep);
  1436. }
  1437. hcd->driver->check_bandwidth(hcd, udev);
  1438. return 0;
  1439. }
  1440. /* Check if the HCD says there's enough bandwidth. Enable all endpoints
  1441. * each interface's alt setting 0 and ask the HCD to check the bandwidth
  1442. * of the bus. There will always be bandwidth for endpoint 0, so it's
  1443. * ok to exclude it.
  1444. */
  1445. if (new_config) {
  1446. num_intfs = new_config->desc.bNumInterfaces;
  1447. /* Remove endpoints (except endpoint 0, which is always on the
  1448. * schedule) from the old config from the schedule
  1449. */
  1450. for (i = 1; i < 16; ++i) {
  1451. ep = udev->ep_out[i];
  1452. if (ep) {
  1453. ret = hcd->driver->drop_endpoint(hcd, udev, ep);
  1454. if (ret < 0)
  1455. goto reset;
  1456. }
  1457. ep = udev->ep_in[i];
  1458. if (ep) {
  1459. ret = hcd->driver->drop_endpoint(hcd, udev, ep);
  1460. if (ret < 0)
  1461. goto reset;
  1462. }
  1463. }
  1464. for (i = 0; i < num_intfs; ++i) {
  1465. /* Set up endpoints for alternate interface setting 0 */
  1466. alt = usb_find_alt_setting(new_config, i, 0);
  1467. if (!alt)
  1468. /* No alt setting 0? Pick the first setting. */
  1469. alt = &new_config->intf_cache[i]->altsetting[0];
  1470. for (j = 0; j < alt->desc.bNumEndpoints; j++) {
  1471. ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]);
  1472. if (ret < 0)
  1473. goto reset;
  1474. }
  1475. }
  1476. }
  1477. if (cur_alt && new_alt) {
  1478. /* Drop all the endpoints in the current alt setting */
  1479. for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) {
  1480. ret = hcd->driver->drop_endpoint(hcd, udev,
  1481. &cur_alt->endpoint[i]);
  1482. if (ret < 0)
  1483. goto reset;
  1484. }
  1485. /* Add all the endpoints in the new alt setting */
  1486. for (i = 0; i < new_alt->desc.bNumEndpoints; i++) {
  1487. ret = hcd->driver->add_endpoint(hcd, udev,
  1488. &new_alt->endpoint[i]);
  1489. if (ret < 0)
  1490. goto reset;
  1491. }
  1492. }
  1493. ret = hcd->driver->check_bandwidth(hcd, udev);
  1494. reset:
  1495. if (ret < 0)
  1496. hcd->driver->reset_bandwidth(hcd, udev);
  1497. return ret;
  1498. }
  1499. /* Disables the endpoint: synchronizes with the hcd to make sure all
  1500. * endpoint state is gone from hardware. usb_hcd_flush_endpoint() must
  1501. * have been called previously. Use for set_configuration, set_interface,
  1502. * driver removal, physical disconnect.
  1503. *
  1504. * example: a qh stored in ep->hcpriv, holding state related to endpoint
  1505. * type, maxpacket size, toggle, halt status, and scheduling.
  1506. */
  1507. void usb_hcd_disable_endpoint(struct usb_device *udev,
  1508. struct usb_host_endpoint *ep)
  1509. {
  1510. struct usb_hcd *hcd;
  1511. might_sleep();
  1512. hcd = bus_to_hcd(udev->bus);
  1513. if (hcd->driver->endpoint_disable)
  1514. hcd->driver->endpoint_disable(hcd, ep);
  1515. }
  1516. /**
  1517. * usb_hcd_reset_endpoint - reset host endpoint state
  1518. * @udev: USB device.
  1519. * @ep: the endpoint to reset.
  1520. *
  1521. * Resets any host endpoint state such as the toggle bit, sequence
  1522. * number and current window.
  1523. */
  1524. void usb_hcd_reset_endpoint(struct usb_device *udev,
  1525. struct usb_host_endpoint *ep)
  1526. {
  1527. struct usb_hcd *hcd = bus_to_hcd(udev->bus);
  1528. if (hcd->driver->endpoint_reset)
  1529. hcd->driver->endpoint_reset(hcd, ep);
  1530. else {
  1531. int epnum = usb_endpoint_num(&ep->desc);
  1532. int is_out = usb_endpoint_dir_out(&ep->desc);
  1533. int is_control = usb_endpoint_xfer_control(&ep->desc);
  1534. usb_settoggle(udev, epnum, is_out, 0);
  1535. if (is_control)
  1536. usb_settoggle(udev, epnum, !is_out, 0);
  1537. }
  1538. }
  1539. /* Protect against drivers that try to unlink URBs after the device
  1540. * is gone, by waiting until all unlinks for @udev are finished.
  1541. * Since we don't currently track URBs by device, simply wait until
  1542. * nothing is running in the locked region of usb_hcd_unlink_urb().
  1543. */
  1544. void usb_hcd_synchronize_unlinks(struct usb_device *udev)
  1545. {
  1546. spin_lock_irq(&hcd_urb_unlink_lock);
  1547. spin_unlock_irq(&hcd_urb_unlink_lock);
  1548. }
  1549. /*-------------------------------------------------------------------------*/
  1550. /* called in any context */
  1551. int usb_hcd_get_frame_number (struct usb_device *udev)
  1552. {
  1553. struct usb_hcd *hcd = bus_to_hcd(udev->bus);
  1554. if (!HC_IS_RUNNING (hcd->state))
  1555. return -ESHUTDOWN;
  1556. return hcd->driver->get_frame_number (hcd);
  1557. }
  1558. /*-------------------------------------------------------------------------*/
  1559. #ifdef CONFIG_PM
  1560. int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg)
  1561. {
  1562. struct usb_hcd *hcd = container_of(rhdev->bus, struct usb_hcd, self);
  1563. int status;
  1564. int old_state = hcd->state;
  1565. dev_dbg(&rhdev->dev, "bus %s%s\n",
  1566. (msg.event & PM_EVENT_AUTO ? "auto-" : ""), "suspend");
  1567. if (!hcd->driver->bus_suspend) {
  1568. status = -ENOENT;
  1569. } else {
  1570. hcd->state = HC_STATE_QUIESCING;
  1571. status = hcd->driver->bus_suspend(hcd);
  1572. }
  1573. if (status == 0) {
  1574. usb_set_device_state(rhdev, USB_STATE_SUSPENDED);
  1575. hcd->state = HC_STATE_SUSPENDED;
  1576. } else {
  1577. hcd->state = old_state;
  1578. dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
  1579. "suspend", status);
  1580. }
  1581. return status;
  1582. }
  1583. int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
  1584. {
  1585. struct usb_hcd *hcd = container_of(rhdev->bus, struct usb_hcd, self);
  1586. int status;
  1587. int old_state = hcd->state;
  1588. dev_dbg(&rhdev->dev, "usb %s%s\n",
  1589. (msg.event & PM_EVENT_AUTO ? "auto-" : ""), "resume");
  1590. if (!hcd->driver->bus_resume)
  1591. return -ENOENT;
  1592. if (hcd->state == HC_STATE_RUNNING)
  1593. return 0;
  1594. hcd->state = HC_STATE_RESUMING;
  1595. status = hcd->driver->bus_resume(hcd);
  1596. if (status == 0) {
  1597. /* TRSMRCY = 10 msec */
  1598. msleep(10);
  1599. usb_set_device_state(rhdev, rhdev->actconfig
  1600. ? USB_STATE_CONFIGURED
  1601. : USB_STATE_ADDRESS);
  1602. hcd->state = HC_STATE_RUNNING;
  1603. } else {
  1604. hcd->state = old_state;
  1605. dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
  1606. "resume", status);
  1607. if (status != -ESHUTDOWN)
  1608. usb_hc_died(hcd);
  1609. }
  1610. return status;
  1611. }
  1612. /* Workqueue routine for root-hub remote wakeup */
  1613. static void hcd_resume_work(struct work_struct *work)
  1614. {
  1615. struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work);
  1616. struct usb_device *udev = hcd->self.root_hub;
  1617. usb_lock_device(udev);
  1618. usb_mark_last_busy(udev);
  1619. usb_external_resume_device(udev, PMSG_REMOTE_RESUME);
  1620. usb_unlock_device(udev);
  1621. }
  1622. /**
  1623. * usb_hcd_resume_root_hub - called by HCD to resume its root hub
  1624. * @hcd: host controller for this root hub
  1625. *
  1626. * The USB host controller calls this function when its root hub is
  1627. * suspended (with the remote wakeup feature enabled) and a remote
  1628. * wakeup request is received. The routine submits a workqueue request
  1629. * to resume the root hub (that is, manage its downstream ports again).
  1630. */
  1631. void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
  1632. {
  1633. unsigned long flags;
  1634. spin_lock_irqsave (&hcd_root_hub_lock, flags);
  1635. if (hcd->rh_registered)
  1636. queue_work(ksuspend_usb_wq, &hcd->wakeup_work);
  1637. spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
  1638. }
  1639. EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
  1640. #endif
  1641. /*-------------------------------------------------------------------------*/
  1642. #ifdef CONFIG_USB_OTG
  1643. /**
  1644. * usb_bus_start_enum - start immediate enumeration (for OTG)
  1645. * @bus: the bus (must use hcd framework)
  1646. * @port_num: 1-based number of port; usually bus->otg_port
  1647. * Context: in_interrupt()
  1648. *
  1649. * Starts enumeration, with an immediate reset followed later by
  1650. * khubd identifying and possibly configuring the device.
  1651. * This is needed by OTG controller drivers, where it helps meet
  1652. * HNP protocol timing requirements for starting a port reset.
  1653. */
  1654. int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
  1655. {
  1656. struct usb_hcd *hcd;
  1657. int status = -EOPNOTSUPP;
  1658. /* NOTE: since HNP can't start by grabbing the bus's address0_sem,
  1659. * boards with root hubs hooked up to internal devices (instead of
  1660. * just the OTG port) may need more attention to resetting...
  1661. */
  1662. hcd = container_of (bus, struct usb_hcd, self);
  1663. if (port_num && hcd->driver->start_port_reset)
  1664. status = hcd->driver->start_port_reset(hcd, port_num);
  1665. /* run khubd shortly after (first) root port reset finishes;
  1666. * it may issue others, until at least 50 msecs have passed.
  1667. */
  1668. if (status == 0)
  1669. mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
  1670. return status;
  1671. }
  1672. EXPORT_SYMBOL_GPL(usb_bus_start_enum);
  1673. #endif
  1674. /*-------------------------------------------------------------------------*/
  1675. /**
  1676. * usb_hcd_irq - hook IRQs to HCD framework (bus glue)
  1677. * @irq: the IRQ being raised
  1678. * @__hcd: pointer to the HCD whose IRQ is being signaled
  1679. *
  1680. * If the controller isn't HALTed, calls the driver's irq handler.
  1681. * Checks whether the controller is now dead.
  1682. */
  1683. irqreturn_t usb_hcd_irq (int irq, void *__hcd)
  1684. {
  1685. struct usb_hcd *hcd = __hcd;
  1686. unsigned long flags;
  1687. irqreturn_t rc;
  1688. /* IRQF_DISABLED doesn't work correctly with shared IRQs
  1689. * when the first handler doesn't use it. So let's just
  1690. * assume it's never used.
  1691. */
  1692. local_irq_save(flags);
  1693. if (unlikely(hcd->state == HC_STATE_HALT ||
  1694. !test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags))) {
  1695. rc = IRQ_NONE;
  1696. } else if (hcd->driver->irq(hcd) == IRQ_NONE) {
  1697. rc = IRQ_NONE;
  1698. } else {
  1699. set_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);
  1700. if (unlikely(hcd->state == HC_STATE_HALT))
  1701. usb_hc_died(hcd);
  1702. rc = IRQ_HANDLED;
  1703. }
  1704. local_irq_restore(flags);
  1705. return rc;
  1706. }
  1707. /*-------------------------------------------------------------------------*/
  1708. /**
  1709. * usb_hc_died - report abnormal shutdown of a host controller (bus glue)
  1710. * @hcd: pointer to the HCD representing the controller
  1711. *
  1712. * This is called by bus glue to report a USB host controller that died
  1713. * while operations may still have been pending. It's called automatically
  1714. * by the PCI glue, so only glue for non-PCI busses should need to call it.
  1715. */
  1716. void usb_hc_died (struct usb_hcd *hcd)
  1717. {
  1718. unsigned long flags;
  1719. dev_err (hcd->self.controller, "HC died; cleaning up\n");
  1720. spin_lock_irqsave (&hcd_root_hub_lock, flags);
  1721. if (hcd->rh_registered) {
  1722. hcd->poll_rh = 0;
  1723. /* make khubd clean up old urbs and devices */
  1724. usb_set_device_state (hcd->self.root_hub,
  1725. USB_STATE_NOTATTACHED);
  1726. usb_kick_khubd (hcd->self.root_hub);
  1727. }
  1728. spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
  1729. }
  1730. EXPORT_SYMBOL_GPL (usb_hc_died);
  1731. /*-------------------------------------------------------------------------*/
  1732. /**
  1733. * usb_create_hcd - create and initialize an HCD structure
  1734. * @driver: HC driver that will use this hcd
  1735. * @dev: device for this HC, stored in hcd->self.controller
  1736. * @bus_name: value to store in hcd->self.bus_name
  1737. * Context: !in_interrupt()
  1738. *
  1739. * Allocate a struct usb_hcd, with extra space at the end for the
  1740. * HC driver's private data. Initialize the generic members of the
  1741. * hcd structure.
  1742. *
  1743. * If memory is unavailable, returns NULL.
  1744. */
  1745. struct usb_hcd *usb_create_hcd (const struct hc_driver *driver,
  1746. struct device *dev, const char *bus_name)
  1747. {
  1748. struct usb_hcd *hcd;
  1749. hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
  1750. if (!hcd) {
  1751. dev_dbg (dev, "hcd alloc failed\n");
  1752. return NULL;
  1753. }
  1754. dev_set_drvdata(dev, hcd);
  1755. kref_init(&hcd->kref);
  1756. usb_bus_init(&hcd->self);
  1757. hcd->self.controller = dev;
  1758. hcd->self.bus_name = bus_name;
  1759. hcd->self.uses_dma = (dev->dma_mask != NULL);
  1760. init_timer(&hcd->rh_timer);
  1761. hcd->rh_timer.function = rh_timer_func;
  1762. hcd->rh_timer.data = (unsigned long) hcd;
  1763. #ifdef CONFIG_PM
  1764. INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
  1765. #endif
  1766. mutex_init(&hcd->bandwidth_mutex);
  1767. hcd->driver = driver;
  1768. hcd->product_desc = (driver->product_desc) ? driver->product_desc :
  1769. "USB Host Controller";
  1770. return hcd;
  1771. }
  1772. EXPORT_SYMBOL_GPL(usb_create_hcd);
  1773. static void hcd_release (struct kref *kref)
  1774. {
  1775. struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref);
  1776. kfree(hcd);
  1777. }
  1778. struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd)
  1779. {
  1780. if (hcd)
  1781. kref_get (&hcd->kref);
  1782. return hcd;
  1783. }
  1784. EXPORT_SYMBOL_GPL(usb_get_hcd);
  1785. void usb_put_hcd (struct usb_hcd *hcd)
  1786. {
  1787. if (hcd)
  1788. kref_put (&hcd->kref, hcd_release);
  1789. }
  1790. EXPORT_SYMBOL_GPL(usb_put_hcd);
  1791. /**
  1792. * usb_add_hcd - finish generic HCD structure initialization and register
  1793. * @hcd: the usb_hcd structure to initialize
  1794. * @irqnum: Interrupt line to allocate
  1795. * @irqflags: Interrupt type flags
  1796. *
  1797. * Finish the remaining parts of generic HCD initialization: allocate the
  1798. * buffers of consistent memory, register the bus, request the IRQ line,
  1799. * and call the driver's reset() and start() routines.
  1800. */
  1801. int usb_add_hcd(struct usb_hcd *hcd,
  1802. unsigned int irqnum, unsigned long irqflags)
  1803. {
  1804. int retval;
  1805. struct usb_device *rhdev;
  1806. dev_info(hcd->self.controller, "%s\n", hcd->product_desc);
  1807. hcd->authorized_default = hcd->wireless? 0 : 1;
  1808. set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
  1809. /* HC is in reset state, but accessible. Now do the one-time init,
  1810. * bottom up so that hcds can customize the root hubs before khubd
  1811. * starts talking to them. (Note, bus id is assigned early too.)
  1812. */
  1813. if ((retval = hcd_buffer_create(hcd)) != 0) {
  1814. dev_dbg(hcd->self.controller, "pool alloc failed\n");
  1815. return retval;
  1816. }
  1817. if ((retval = usb_register_bus(&hcd->self)) < 0)
  1818. goto err_register_bus;
  1819. if ((rhdev = usb_alloc_dev(NULL, &hcd->self, 0)) == NULL) {
  1820. dev_err(hcd->self.controller, "unable to allocate root hub\n");
  1821. retval = -ENOMEM;
  1822. goto err_allocate_root_hub;
  1823. }
  1824. switch (hcd->driver->flags & HCD_MASK) {
  1825. case HCD_USB11:
  1826. rhdev->speed = USB_SPEED_FULL;
  1827. break;
  1828. case HCD_USB2:
  1829. rhdev->speed = USB_SPEED_HIGH;
  1830. break;
  1831. case HCD_USB3:
  1832. rhdev->speed = USB_SPEED_SUPER;
  1833. break;
  1834. default:
  1835. goto err_allocate_root_hub;
  1836. }
  1837. hcd->self.root_hub = rhdev;
  1838. /* wakeup flag init defaults to "everything works" for root hubs,
  1839. * but drivers can override it in reset() if needed, along with
  1840. * recording the overall controller's system wakeup capability.
  1841. */
  1842. device_init_wakeup(&rhdev->dev, 1);
  1843. /* "reset" is misnamed; its role is now one-time init. the controller
  1844. * should already have been reset (and boot firmware kicked off etc).
  1845. */
  1846. if (hcd->driver->reset && (retval = hcd->driver->reset(hcd)) < 0) {
  1847. dev_err(hcd->self.controller, "can't setup\n");
  1848. goto err_hcd_driver_setup;
  1849. }
  1850. /* NOTE: root hub and controller capabilities may not be the same */
  1851. if (device_can_wakeup(hcd->self.controller)
  1852. && device_can_wakeup(&hcd->self.root_hub->dev))
  1853. dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
  1854. /* enable irqs just before we start the controller */
  1855. if (hcd->driver->irq) {
  1856. /* IRQF_DISABLED doesn't work as advertised when used together
  1857. * with IRQF_SHARED. As usb_hcd_irq() will always disable
  1858. * interrupts we can remove it here.
  1859. */
  1860. if (irqflags & IRQF_SHARED)
  1861. irqflags &= ~IRQF_DISABLED;
  1862. snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
  1863. hcd->driver->description, hcd->self.busnum);
  1864. if ((retval = request_irq(irqnum, &usb_hcd_irq, irqflags,
  1865. hcd->irq_descr, hcd)) != 0) {
  1866. dev_err(hcd->self.controller,
  1867. "request interrupt %d failed\n", irqnum);
  1868. goto err_request_irq;
  1869. }
  1870. hcd->irq = irqnum;
  1871. dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum,
  1872. (hcd->driver->flags & HCD_MEMORY) ?
  1873. "io mem" : "io base",
  1874. (unsigned long long)hcd->rsrc_start);
  1875. } else {
  1876. hcd->irq = -1;
  1877. if (hcd->rsrc_start)
  1878. dev_info(hcd->self.controller, "%s 0x%08llx\n",
  1879. (hcd->driver->flags & HCD_MEMORY) ?
  1880. "io mem" : "io base",
  1881. (unsigned long long)hcd->rsrc_start);
  1882. }
  1883. if ((retval = hcd->driver->start(hcd)) < 0) {
  1884. dev_err(hcd->self.controller, "startup error %d\n", retval);
  1885. goto err_hcd_driver_start;
  1886. }
  1887. /* starting here, usbcore will pay attention to this root hub */
  1888. rhdev->bus_mA = min(500u, hcd->power_budget);
  1889. if ((retval = register_root_hub(hcd)) != 0)
  1890. goto err_register_root_hub;
  1891. retval = sysfs_create_group(&rhdev->dev.kobj, &usb_bus_attr_group);
  1892. if (retval < 0) {
  1893. printk(KERN_ERR "Cannot register USB bus sysfs attributes: %d\n",
  1894. retval);
  1895. goto error_create_attr_group;
  1896. }
  1897. if (hcd->uses_new_polling && hcd->poll_rh)
  1898. usb_hcd_poll_rh_status(hcd);
  1899. return retval;
  1900. error_create_attr_group:
  1901. mutex_lock(&usb_bus_list_lock);
  1902. usb_disconnect(&hcd->self.root_hub);
  1903. mutex_unlock(&usb_bus_list_lock);
  1904. err_register_root_hub:
  1905. hcd->driver->stop(hcd);
  1906. err_hcd_driver_start:
  1907. if (hcd->irq >= 0)
  1908. free_irq(irqnum, hcd);
  1909. err_request_irq:
  1910. err_hcd_driver_setup:
  1911. hcd->self.root_hub = NULL;
  1912. usb_put_dev(rhdev);
  1913. err_allocate_root_hub:
  1914. usb_deregister_bus(&hcd->self);
  1915. err_register_bus:
  1916. hcd_buffer_destroy(hcd);
  1917. return retval;
  1918. }
  1919. EXPORT_SYMBOL_GPL(usb_add_hcd);
  1920. /**
  1921. * usb_remove_hcd - shutdown processing for generic HCDs
  1922. * @hcd: the usb_hcd structure to remove
  1923. * Context: !in_interrupt()
  1924. *
  1925. * Disconnects the root hub, then reverses the effects of usb_add_hcd(),
  1926. * invoking the HCD's stop() method.
  1927. */
  1928. void usb_remove_hcd(struct usb_hcd *hcd)
  1929. {
  1930. dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);
  1931. if (HC_IS_RUNNING (hcd->state))
  1932. hcd->state = HC_STATE_QUIESCING;
  1933. dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
  1934. spin_lock_irq (&hcd_root_hub_lock);
  1935. hcd->rh_registered = 0;
  1936. spin_unlock_irq (&hcd_root_hub_lock);
  1937. #ifdef CONFIG_PM
  1938. cancel_work_sync(&hcd->wakeup_work);
  1939. #endif
  1940. sysfs_remove_group(&hcd->self.root_hub->dev.kobj, &usb_bus_attr_group);
  1941. mutex_lock(&usb_bus_list_lock);
  1942. usb_disconnect(&hcd->self.root_hub);
  1943. mutex_unlock(&usb_bus_list_lock);
  1944. hcd->driver->stop(hcd);
  1945. hcd->state = HC_STATE_HALT;
  1946. hcd->poll_rh = 0;
  1947. del_timer_sync(&hcd->rh_timer);
  1948. if (hcd->irq >= 0)
  1949. free_irq(hcd->irq, hcd);
  1950. usb_deregister_bus(&hcd->self);
  1951. hcd_buffer_destroy(hcd);
  1952. }
  1953. EXPORT_SYMBOL_GPL(usb_remove_hcd);
  1954. void
  1955. usb_hcd_platform_shutdown(struct platform_device* dev)
  1956. {
  1957. struct usb_hcd *hcd = platform_get_drvdata(dev);
  1958. if (hcd->driver->shutdown)
  1959. hcd->driver->shutdown(hcd);
  1960. }
  1961. EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown);
  1962. /*-------------------------------------------------------------------------*/
  1963. #if defined(CONFIG_USB_MON) || defined(CONFIG_USB_MON_MODULE)
  1964. struct usb_mon_operations *mon_ops;
  1965. /*
  1966. * The registration is unlocked.
  1967. * We do it this way because we do not want to lock in hot paths.
  1968. *
  1969. * Notice that the code is minimally error-proof. Because usbmon needs
  1970. * symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
  1971. */
  1972. int usb_mon_register (struct usb_mon_operations *ops)
  1973. {
  1974. if (mon_ops)
  1975. return -EBUSY;
  1976. mon_ops = ops;
  1977. mb();
  1978. return 0;
  1979. }
  1980. EXPORT_SYMBOL_GPL (usb_mon_register);
  1981. void usb_mon_deregister (void)
  1982. {
  1983. if (mon_ops == NULL) {
  1984. printk(KERN_ERR "USB: monitor was not registered\n");
  1985. return;
  1986. }
  1987. mon_ops = NULL;
  1988. mb();
  1989. }
  1990. EXPORT_SYMBOL_GPL (usb_mon_deregister);
  1991. #endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */