hub.c 83 KB

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  1. /*
  2. * USB hub driver.
  3. *
  4. * (C) Copyright 1999 Linus Torvalds
  5. * (C) Copyright 1999 Johannes Erdfelt
  6. * (C) Copyright 1999 Gregory P. Smith
  7. * (C) Copyright 2001 Brad Hards (bhards@bigpond.net.au)
  8. *
  9. */
  10. #include <linux/config.h>
  11. #include <linux/kernel.h>
  12. #include <linux/errno.h>
  13. #include <linux/module.h>
  14. #include <linux/moduleparam.h>
  15. #include <linux/completion.h>
  16. #include <linux/sched.h>
  17. #include <linux/list.h>
  18. #include <linux/slab.h>
  19. #include <linux/smp_lock.h>
  20. #include <linux/ioctl.h>
  21. #include <linux/usb.h>
  22. #include <linux/usbdevice_fs.h>
  23. #include <linux/kthread.h>
  24. #include <linux/mutex.h>
  25. #include <asm/semaphore.h>
  26. #include <asm/uaccess.h>
  27. #include <asm/byteorder.h>
  28. #include "usb.h"
  29. #include "hcd.h"
  30. #include "hub.h"
  31. /* Protect struct usb_device->state and ->children members
  32. * Note: Both are also protected by ->dev.sem, except that ->state can
  33. * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
  34. static DEFINE_SPINLOCK(device_state_lock);
  35. /* khubd's worklist and its lock */
  36. static DEFINE_SPINLOCK(hub_event_lock);
  37. static LIST_HEAD(hub_event_list); /* List of hubs needing servicing */
  38. /* Wakes up khubd */
  39. static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
  40. static struct task_struct *khubd_task;
  41. /* cycle leds on hubs that aren't blinking for attention */
  42. static int blinkenlights = 0;
  43. module_param (blinkenlights, bool, S_IRUGO);
  44. MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
  45. /*
  46. * As of 2.6.10 we introduce a new USB device initialization scheme which
  47. * closely resembles the way Windows works. Hopefully it will be compatible
  48. * with a wider range of devices than the old scheme. However some previously
  49. * working devices may start giving rise to "device not accepting address"
  50. * errors; if that happens the user can try the old scheme by adjusting the
  51. * following module parameters.
  52. *
  53. * For maximum flexibility there are two boolean parameters to control the
  54. * hub driver's behavior. On the first initialization attempt, if the
  55. * "old_scheme_first" parameter is set then the old scheme will be used,
  56. * otherwise the new scheme is used. If that fails and "use_both_schemes"
  57. * is set, then the driver will make another attempt, using the other scheme.
  58. */
  59. static int old_scheme_first = 0;
  60. module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
  61. MODULE_PARM_DESC(old_scheme_first,
  62. "start with the old device initialization scheme");
  63. static int use_both_schemes = 1;
  64. module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
  65. MODULE_PARM_DESC(use_both_schemes,
  66. "try the other device initialization scheme if the "
  67. "first one fails");
  68. #ifdef DEBUG
  69. static inline char *portspeed (int portstatus)
  70. {
  71. if (portstatus & (1 << USB_PORT_FEAT_HIGHSPEED))
  72. return "480 Mb/s";
  73. else if (portstatus & (1 << USB_PORT_FEAT_LOWSPEED))
  74. return "1.5 Mb/s";
  75. else
  76. return "12 Mb/s";
  77. }
  78. #endif
  79. /* Note that hdev or one of its children must be locked! */
  80. static inline struct usb_hub *hdev_to_hub(struct usb_device *hdev)
  81. {
  82. return usb_get_intfdata(hdev->actconfig->interface[0]);
  83. }
  84. /* USB 2.0 spec Section 11.24.4.5 */
  85. static int get_hub_descriptor(struct usb_device *hdev, void *data, int size)
  86. {
  87. int i, ret;
  88. for (i = 0; i < 3; i++) {
  89. ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
  90. USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
  91. USB_DT_HUB << 8, 0, data, size,
  92. USB_CTRL_GET_TIMEOUT);
  93. if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
  94. return ret;
  95. }
  96. return -EINVAL;
  97. }
  98. /*
  99. * USB 2.0 spec Section 11.24.2.1
  100. */
  101. static int clear_hub_feature(struct usb_device *hdev, int feature)
  102. {
  103. return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
  104. USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
  105. }
  106. /*
  107. * USB 2.0 spec Section 11.24.2.2
  108. */
  109. static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
  110. {
  111. return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
  112. USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
  113. NULL, 0, 1000);
  114. }
  115. /*
  116. * USB 2.0 spec Section 11.24.2.13
  117. */
  118. static int set_port_feature(struct usb_device *hdev, int port1, int feature)
  119. {
  120. return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
  121. USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
  122. NULL, 0, 1000);
  123. }
  124. /*
  125. * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
  126. * for info about using port indicators
  127. */
  128. static void set_port_led(
  129. struct usb_hub *hub,
  130. int port1,
  131. int selector
  132. )
  133. {
  134. int status = set_port_feature(hub->hdev, (selector << 8) | port1,
  135. USB_PORT_FEAT_INDICATOR);
  136. if (status < 0)
  137. dev_dbg (hub->intfdev,
  138. "port %d indicator %s status %d\n",
  139. port1,
  140. ({ char *s; switch (selector) {
  141. case HUB_LED_AMBER: s = "amber"; break;
  142. case HUB_LED_GREEN: s = "green"; break;
  143. case HUB_LED_OFF: s = "off"; break;
  144. case HUB_LED_AUTO: s = "auto"; break;
  145. default: s = "??"; break;
  146. }; s; }),
  147. status);
  148. }
  149. #define LED_CYCLE_PERIOD ((2*HZ)/3)
  150. static void led_work (void *__hub)
  151. {
  152. struct usb_hub *hub = __hub;
  153. struct usb_device *hdev = hub->hdev;
  154. unsigned i;
  155. unsigned changed = 0;
  156. int cursor = -1;
  157. if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
  158. return;
  159. for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
  160. unsigned selector, mode;
  161. /* 30%-50% duty cycle */
  162. switch (hub->indicator[i]) {
  163. /* cycle marker */
  164. case INDICATOR_CYCLE:
  165. cursor = i;
  166. selector = HUB_LED_AUTO;
  167. mode = INDICATOR_AUTO;
  168. break;
  169. /* blinking green = sw attention */
  170. case INDICATOR_GREEN_BLINK:
  171. selector = HUB_LED_GREEN;
  172. mode = INDICATOR_GREEN_BLINK_OFF;
  173. break;
  174. case INDICATOR_GREEN_BLINK_OFF:
  175. selector = HUB_LED_OFF;
  176. mode = INDICATOR_GREEN_BLINK;
  177. break;
  178. /* blinking amber = hw attention */
  179. case INDICATOR_AMBER_BLINK:
  180. selector = HUB_LED_AMBER;
  181. mode = INDICATOR_AMBER_BLINK_OFF;
  182. break;
  183. case INDICATOR_AMBER_BLINK_OFF:
  184. selector = HUB_LED_OFF;
  185. mode = INDICATOR_AMBER_BLINK;
  186. break;
  187. /* blink green/amber = reserved */
  188. case INDICATOR_ALT_BLINK:
  189. selector = HUB_LED_GREEN;
  190. mode = INDICATOR_ALT_BLINK_OFF;
  191. break;
  192. case INDICATOR_ALT_BLINK_OFF:
  193. selector = HUB_LED_AMBER;
  194. mode = INDICATOR_ALT_BLINK;
  195. break;
  196. default:
  197. continue;
  198. }
  199. if (selector != HUB_LED_AUTO)
  200. changed = 1;
  201. set_port_led(hub, i + 1, selector);
  202. hub->indicator[i] = mode;
  203. }
  204. if (!changed && blinkenlights) {
  205. cursor++;
  206. cursor %= hub->descriptor->bNbrPorts;
  207. set_port_led(hub, cursor + 1, HUB_LED_GREEN);
  208. hub->indicator[cursor] = INDICATOR_CYCLE;
  209. changed++;
  210. }
  211. if (changed)
  212. schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
  213. }
  214. /* use a short timeout for hub/port status fetches */
  215. #define USB_STS_TIMEOUT 1000
  216. #define USB_STS_RETRIES 5
  217. /*
  218. * USB 2.0 spec Section 11.24.2.6
  219. */
  220. static int get_hub_status(struct usb_device *hdev,
  221. struct usb_hub_status *data)
  222. {
  223. int i, status = -ETIMEDOUT;
  224. for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
  225. status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
  226. USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
  227. data, sizeof(*data), USB_STS_TIMEOUT);
  228. }
  229. return status;
  230. }
  231. /*
  232. * USB 2.0 spec Section 11.24.2.7
  233. */
  234. static int get_port_status(struct usb_device *hdev, int port1,
  235. struct usb_port_status *data)
  236. {
  237. int i, status = -ETIMEDOUT;
  238. for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
  239. status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
  240. USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
  241. data, sizeof(*data), USB_STS_TIMEOUT);
  242. }
  243. return status;
  244. }
  245. static void kick_khubd(struct usb_hub *hub)
  246. {
  247. unsigned long flags;
  248. spin_lock_irqsave(&hub_event_lock, flags);
  249. if (list_empty(&hub->event_list)) {
  250. list_add_tail(&hub->event_list, &hub_event_list);
  251. wake_up(&khubd_wait);
  252. }
  253. spin_unlock_irqrestore(&hub_event_lock, flags);
  254. }
  255. void usb_kick_khubd(struct usb_device *hdev)
  256. {
  257. kick_khubd(hdev_to_hub(hdev));
  258. }
  259. /* completion function, fires on port status changes and various faults */
  260. static void hub_irq(struct urb *urb, struct pt_regs *regs)
  261. {
  262. struct usb_hub *hub = (struct usb_hub *)urb->context;
  263. int status;
  264. int i;
  265. unsigned long bits;
  266. switch (urb->status) {
  267. case -ENOENT: /* synchronous unlink */
  268. case -ECONNRESET: /* async unlink */
  269. case -ESHUTDOWN: /* hardware going away */
  270. return;
  271. default: /* presumably an error */
  272. /* Cause a hub reset after 10 consecutive errors */
  273. dev_dbg (hub->intfdev, "transfer --> %d\n", urb->status);
  274. if ((++hub->nerrors < 10) || hub->error)
  275. goto resubmit;
  276. hub->error = urb->status;
  277. /* FALL THROUGH */
  278. /* let khubd handle things */
  279. case 0: /* we got data: port status changed */
  280. bits = 0;
  281. for (i = 0; i < urb->actual_length; ++i)
  282. bits |= ((unsigned long) ((*hub->buffer)[i]))
  283. << (i*8);
  284. hub->event_bits[0] = bits;
  285. break;
  286. }
  287. hub->nerrors = 0;
  288. /* Something happened, let khubd figure it out */
  289. kick_khubd(hub);
  290. resubmit:
  291. if (hub->quiescing)
  292. return;
  293. if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
  294. && status != -ENODEV && status != -EPERM)
  295. dev_err (hub->intfdev, "resubmit --> %d\n", status);
  296. }
  297. /* USB 2.0 spec Section 11.24.2.3 */
  298. static inline int
  299. hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
  300. {
  301. return usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
  302. HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
  303. tt, NULL, 0, 1000);
  304. }
  305. /*
  306. * enumeration blocks khubd for a long time. we use keventd instead, since
  307. * long blocking there is the exception, not the rule. accordingly, HCDs
  308. * talking to TTs must queue control transfers (not just bulk and iso), so
  309. * both can talk to the same hub concurrently.
  310. */
  311. static void hub_tt_kevent (void *arg)
  312. {
  313. struct usb_hub *hub = arg;
  314. unsigned long flags;
  315. spin_lock_irqsave (&hub->tt.lock, flags);
  316. while (!list_empty (&hub->tt.clear_list)) {
  317. struct list_head *temp;
  318. struct usb_tt_clear *clear;
  319. struct usb_device *hdev = hub->hdev;
  320. int status;
  321. temp = hub->tt.clear_list.next;
  322. clear = list_entry (temp, struct usb_tt_clear, clear_list);
  323. list_del (&clear->clear_list);
  324. /* drop lock so HCD can concurrently report other TT errors */
  325. spin_unlock_irqrestore (&hub->tt.lock, flags);
  326. status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
  327. spin_lock_irqsave (&hub->tt.lock, flags);
  328. if (status)
  329. dev_err (&hdev->dev,
  330. "clear tt %d (%04x) error %d\n",
  331. clear->tt, clear->devinfo, status);
  332. kfree(clear);
  333. }
  334. spin_unlock_irqrestore (&hub->tt.lock, flags);
  335. }
  336. /**
  337. * usb_hub_tt_clear_buffer - clear control/bulk TT state in high speed hub
  338. * @udev: the device whose split transaction failed
  339. * @pipe: identifies the endpoint of the failed transaction
  340. *
  341. * High speed HCDs use this to tell the hub driver that some split control or
  342. * bulk transaction failed in a way that requires clearing internal state of
  343. * a transaction translator. This is normally detected (and reported) from
  344. * interrupt context.
  345. *
  346. * It may not be possible for that hub to handle additional full (or low)
  347. * speed transactions until that state is fully cleared out.
  348. */
  349. void usb_hub_tt_clear_buffer (struct usb_device *udev, int pipe)
  350. {
  351. struct usb_tt *tt = udev->tt;
  352. unsigned long flags;
  353. struct usb_tt_clear *clear;
  354. /* we've got to cope with an arbitrary number of pending TT clears,
  355. * since each TT has "at least two" buffers that can need it (and
  356. * there can be many TTs per hub). even if they're uncommon.
  357. */
  358. if ((clear = kmalloc (sizeof *clear, SLAB_ATOMIC)) == NULL) {
  359. dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
  360. /* FIXME recover somehow ... RESET_TT? */
  361. return;
  362. }
  363. /* info that CLEAR_TT_BUFFER needs */
  364. clear->tt = tt->multi ? udev->ttport : 1;
  365. clear->devinfo = usb_pipeendpoint (pipe);
  366. clear->devinfo |= udev->devnum << 4;
  367. clear->devinfo |= usb_pipecontrol (pipe)
  368. ? (USB_ENDPOINT_XFER_CONTROL << 11)
  369. : (USB_ENDPOINT_XFER_BULK << 11);
  370. if (usb_pipein (pipe))
  371. clear->devinfo |= 1 << 15;
  372. /* tell keventd to clear state for this TT */
  373. spin_lock_irqsave (&tt->lock, flags);
  374. list_add_tail (&clear->clear_list, &tt->clear_list);
  375. schedule_work (&tt->kevent);
  376. spin_unlock_irqrestore (&tt->lock, flags);
  377. }
  378. static void hub_power_on(struct usb_hub *hub)
  379. {
  380. int port1;
  381. unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
  382. u16 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
  383. /* if hub supports power switching, enable power on each port */
  384. if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2) {
  385. dev_dbg(hub->intfdev, "enabling power on all ports\n");
  386. for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
  387. set_port_feature(hub->hdev, port1,
  388. USB_PORT_FEAT_POWER);
  389. }
  390. /* Wait at least 100 msec for power to become stable */
  391. msleep(max(pgood_delay, (unsigned) 100));
  392. }
  393. static inline void __hub_quiesce(struct usb_hub *hub)
  394. {
  395. /* (nonblocking) khubd and related activity won't re-trigger */
  396. hub->quiescing = 1;
  397. hub->activating = 0;
  398. hub->resume_root_hub = 0;
  399. }
  400. static void hub_quiesce(struct usb_hub *hub)
  401. {
  402. /* (blocking) stop khubd and related activity */
  403. __hub_quiesce(hub);
  404. usb_kill_urb(hub->urb);
  405. if (hub->has_indicators)
  406. cancel_delayed_work(&hub->leds);
  407. if (hub->has_indicators || hub->tt.hub)
  408. flush_scheduled_work();
  409. }
  410. static void hub_activate(struct usb_hub *hub)
  411. {
  412. int status;
  413. hub->quiescing = 0;
  414. hub->activating = 1;
  415. hub->resume_root_hub = 0;
  416. status = usb_submit_urb(hub->urb, GFP_NOIO);
  417. if (status < 0)
  418. dev_err(hub->intfdev, "activate --> %d\n", status);
  419. if (hub->has_indicators && blinkenlights)
  420. schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
  421. /* scan all ports ASAP */
  422. kick_khubd(hub);
  423. }
  424. static int hub_hub_status(struct usb_hub *hub,
  425. u16 *status, u16 *change)
  426. {
  427. int ret;
  428. ret = get_hub_status(hub->hdev, &hub->status->hub);
  429. if (ret < 0)
  430. dev_err (hub->intfdev,
  431. "%s failed (err = %d)\n", __FUNCTION__, ret);
  432. else {
  433. *status = le16_to_cpu(hub->status->hub.wHubStatus);
  434. *change = le16_to_cpu(hub->status->hub.wHubChange);
  435. ret = 0;
  436. }
  437. return ret;
  438. }
  439. static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
  440. {
  441. struct usb_device *hdev = hub->hdev;
  442. int ret;
  443. if (hdev->children[port1-1] && set_state) {
  444. usb_set_device_state(hdev->children[port1-1],
  445. USB_STATE_NOTATTACHED);
  446. }
  447. ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
  448. if (ret)
  449. dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
  450. port1, ret);
  451. return ret;
  452. }
  453. /* caller has locked the hub device */
  454. static void hub_pre_reset(struct usb_hub *hub, int disable_ports)
  455. {
  456. struct usb_device *hdev = hub->hdev;
  457. int port1;
  458. for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
  459. if (hdev->children[port1 - 1]) {
  460. usb_disconnect(&hdev->children[port1 - 1]);
  461. if (disable_ports)
  462. hub_port_disable(hub, port1, 0);
  463. }
  464. }
  465. hub_quiesce(hub);
  466. }
  467. /* caller has locked the hub device */
  468. static void hub_post_reset(struct usb_hub *hub)
  469. {
  470. hub_activate(hub);
  471. hub_power_on(hub);
  472. }
  473. static int hub_configure(struct usb_hub *hub,
  474. struct usb_endpoint_descriptor *endpoint)
  475. {
  476. struct usb_device *hdev = hub->hdev;
  477. struct device *hub_dev = hub->intfdev;
  478. u16 hubstatus, hubchange;
  479. u16 wHubCharacteristics;
  480. unsigned int pipe;
  481. int maxp, ret;
  482. char *message;
  483. hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
  484. &hub->buffer_dma);
  485. if (!hub->buffer) {
  486. message = "can't allocate hub irq buffer";
  487. ret = -ENOMEM;
  488. goto fail;
  489. }
  490. hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
  491. if (!hub->status) {
  492. message = "can't kmalloc hub status buffer";
  493. ret = -ENOMEM;
  494. goto fail;
  495. }
  496. hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
  497. if (!hub->descriptor) {
  498. message = "can't kmalloc hub descriptor";
  499. ret = -ENOMEM;
  500. goto fail;
  501. }
  502. /* Request the entire hub descriptor.
  503. * hub->descriptor can handle USB_MAXCHILDREN ports,
  504. * but the hub can/will return fewer bytes here.
  505. */
  506. ret = get_hub_descriptor(hdev, hub->descriptor,
  507. sizeof(*hub->descriptor));
  508. if (ret < 0) {
  509. message = "can't read hub descriptor";
  510. goto fail;
  511. } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
  512. message = "hub has too many ports!";
  513. ret = -ENODEV;
  514. goto fail;
  515. }
  516. hdev->maxchild = hub->descriptor->bNbrPorts;
  517. dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
  518. (hdev->maxchild == 1) ? "" : "s");
  519. wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
  520. if (wHubCharacteristics & HUB_CHAR_COMPOUND) {
  521. int i;
  522. char portstr [USB_MAXCHILDREN + 1];
  523. for (i = 0; i < hdev->maxchild; i++)
  524. portstr[i] = hub->descriptor->DeviceRemovable
  525. [((i + 1) / 8)] & (1 << ((i + 1) % 8))
  526. ? 'F' : 'R';
  527. portstr[hdev->maxchild] = 0;
  528. dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
  529. } else
  530. dev_dbg(hub_dev, "standalone hub\n");
  531. switch (wHubCharacteristics & HUB_CHAR_LPSM) {
  532. case 0x00:
  533. dev_dbg(hub_dev, "ganged power switching\n");
  534. break;
  535. case 0x01:
  536. dev_dbg(hub_dev, "individual port power switching\n");
  537. break;
  538. case 0x02:
  539. case 0x03:
  540. dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
  541. break;
  542. }
  543. switch (wHubCharacteristics & HUB_CHAR_OCPM) {
  544. case 0x00:
  545. dev_dbg(hub_dev, "global over-current protection\n");
  546. break;
  547. case 0x08:
  548. dev_dbg(hub_dev, "individual port over-current protection\n");
  549. break;
  550. case 0x10:
  551. case 0x18:
  552. dev_dbg(hub_dev, "no over-current protection\n");
  553. break;
  554. }
  555. spin_lock_init (&hub->tt.lock);
  556. INIT_LIST_HEAD (&hub->tt.clear_list);
  557. INIT_WORK (&hub->tt.kevent, hub_tt_kevent, hub);
  558. switch (hdev->descriptor.bDeviceProtocol) {
  559. case 0:
  560. break;
  561. case 1:
  562. dev_dbg(hub_dev, "Single TT\n");
  563. hub->tt.hub = hdev;
  564. break;
  565. case 2:
  566. ret = usb_set_interface(hdev, 0, 1);
  567. if (ret == 0) {
  568. dev_dbg(hub_dev, "TT per port\n");
  569. hub->tt.multi = 1;
  570. } else
  571. dev_err(hub_dev, "Using single TT (err %d)\n",
  572. ret);
  573. hub->tt.hub = hdev;
  574. break;
  575. default:
  576. dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
  577. hdev->descriptor.bDeviceProtocol);
  578. break;
  579. }
  580. /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
  581. switch (wHubCharacteristics & HUB_CHAR_TTTT) {
  582. case HUB_TTTT_8_BITS:
  583. if (hdev->descriptor.bDeviceProtocol != 0) {
  584. hub->tt.think_time = 666;
  585. dev_dbg(hub_dev, "TT requires at most %d "
  586. "FS bit times (%d ns)\n",
  587. 8, hub->tt.think_time);
  588. }
  589. break;
  590. case HUB_TTTT_16_BITS:
  591. hub->tt.think_time = 666 * 2;
  592. dev_dbg(hub_dev, "TT requires at most %d "
  593. "FS bit times (%d ns)\n",
  594. 16, hub->tt.think_time);
  595. break;
  596. case HUB_TTTT_24_BITS:
  597. hub->tt.think_time = 666 * 3;
  598. dev_dbg(hub_dev, "TT requires at most %d "
  599. "FS bit times (%d ns)\n",
  600. 24, hub->tt.think_time);
  601. break;
  602. case HUB_TTTT_32_BITS:
  603. hub->tt.think_time = 666 * 4;
  604. dev_dbg(hub_dev, "TT requires at most %d "
  605. "FS bit times (%d ns)\n",
  606. 32, hub->tt.think_time);
  607. break;
  608. }
  609. /* probe() zeroes hub->indicator[] */
  610. if (wHubCharacteristics & HUB_CHAR_PORTIND) {
  611. hub->has_indicators = 1;
  612. dev_dbg(hub_dev, "Port indicators are supported\n");
  613. }
  614. dev_dbg(hub_dev, "power on to power good time: %dms\n",
  615. hub->descriptor->bPwrOn2PwrGood * 2);
  616. /* power budgeting mostly matters with bus-powered hubs,
  617. * and battery-powered root hubs (may provide just 8 mA).
  618. */
  619. ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
  620. if (ret < 2) {
  621. message = "can't get hub status";
  622. goto fail;
  623. }
  624. le16_to_cpus(&hubstatus);
  625. if (hdev == hdev->bus->root_hub) {
  626. if (hdev->bus_mA == 0 || hdev->bus_mA >= 500)
  627. hub->mA_per_port = 500;
  628. else {
  629. hub->mA_per_port = hdev->bus_mA;
  630. hub->limited_power = 1;
  631. }
  632. } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
  633. dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
  634. hub->descriptor->bHubContrCurrent);
  635. hub->limited_power = 1;
  636. if (hdev->maxchild > 0) {
  637. int remaining = hdev->bus_mA -
  638. hub->descriptor->bHubContrCurrent;
  639. if (remaining < hdev->maxchild * 100)
  640. dev_warn(hub_dev,
  641. "insufficient power available "
  642. "to use all downstream ports\n");
  643. hub->mA_per_port = 100; /* 7.2.1.1 */
  644. }
  645. } else { /* Self-powered external hub */
  646. /* FIXME: What about battery-powered external hubs that
  647. * provide less current per port? */
  648. hub->mA_per_port = 500;
  649. }
  650. if (hub->mA_per_port < 500)
  651. dev_dbg(hub_dev, "%umA bus power budget for each child\n",
  652. hub->mA_per_port);
  653. ret = hub_hub_status(hub, &hubstatus, &hubchange);
  654. if (ret < 0) {
  655. message = "can't get hub status";
  656. goto fail;
  657. }
  658. /* local power status reports aren't always correct */
  659. if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
  660. dev_dbg(hub_dev, "local power source is %s\n",
  661. (hubstatus & HUB_STATUS_LOCAL_POWER)
  662. ? "lost (inactive)" : "good");
  663. if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
  664. dev_dbg(hub_dev, "%sover-current condition exists\n",
  665. (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
  666. /* set up the interrupt endpoint */
  667. pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
  668. maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
  669. if (maxp > sizeof(*hub->buffer))
  670. maxp = sizeof(*hub->buffer);
  671. hub->urb = usb_alloc_urb(0, GFP_KERNEL);
  672. if (!hub->urb) {
  673. message = "couldn't allocate interrupt urb";
  674. ret = -ENOMEM;
  675. goto fail;
  676. }
  677. usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
  678. hub, endpoint->bInterval);
  679. hub->urb->transfer_dma = hub->buffer_dma;
  680. hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
  681. /* maybe cycle the hub leds */
  682. if (hub->has_indicators && blinkenlights)
  683. hub->indicator [0] = INDICATOR_CYCLE;
  684. hub_power_on(hub);
  685. hub_activate(hub);
  686. return 0;
  687. fail:
  688. dev_err (hub_dev, "config failed, %s (err %d)\n",
  689. message, ret);
  690. /* hub_disconnect() frees urb and descriptor */
  691. return ret;
  692. }
  693. static unsigned highspeed_hubs;
  694. static void hub_disconnect(struct usb_interface *intf)
  695. {
  696. struct usb_hub *hub = usb_get_intfdata (intf);
  697. struct usb_device *hdev;
  698. usb_set_intfdata (intf, NULL);
  699. hdev = hub->hdev;
  700. if (hdev->speed == USB_SPEED_HIGH)
  701. highspeed_hubs--;
  702. /* Disconnect all children and quiesce the hub */
  703. hub_pre_reset(hub, 1);
  704. usb_free_urb(hub->urb);
  705. hub->urb = NULL;
  706. spin_lock_irq(&hub_event_lock);
  707. list_del_init(&hub->event_list);
  708. spin_unlock_irq(&hub_event_lock);
  709. kfree(hub->descriptor);
  710. hub->descriptor = NULL;
  711. kfree(hub->status);
  712. hub->status = NULL;
  713. if (hub->buffer) {
  714. usb_buffer_free(hdev, sizeof(*hub->buffer), hub->buffer,
  715. hub->buffer_dma);
  716. hub->buffer = NULL;
  717. }
  718. kfree(hub);
  719. }
  720. static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
  721. {
  722. struct usb_host_interface *desc;
  723. struct usb_endpoint_descriptor *endpoint;
  724. struct usb_device *hdev;
  725. struct usb_hub *hub;
  726. desc = intf->cur_altsetting;
  727. hdev = interface_to_usbdev(intf);
  728. /* Some hubs have a subclass of 1, which AFAICT according to the */
  729. /* specs is not defined, but it works */
  730. if ((desc->desc.bInterfaceSubClass != 0) &&
  731. (desc->desc.bInterfaceSubClass != 1)) {
  732. descriptor_error:
  733. dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
  734. return -EIO;
  735. }
  736. /* Multiple endpoints? What kind of mutant ninja-hub is this? */
  737. if (desc->desc.bNumEndpoints != 1)
  738. goto descriptor_error;
  739. endpoint = &desc->endpoint[0].desc;
  740. /* Output endpoint? Curiouser and curiouser.. */
  741. if (!(endpoint->bEndpointAddress & USB_DIR_IN))
  742. goto descriptor_error;
  743. /* If it's not an interrupt endpoint, we'd better punt! */
  744. if ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
  745. != USB_ENDPOINT_XFER_INT)
  746. goto descriptor_error;
  747. /* We found a hub */
  748. dev_info (&intf->dev, "USB hub found\n");
  749. hub = kzalloc(sizeof(*hub), GFP_KERNEL);
  750. if (!hub) {
  751. dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
  752. return -ENOMEM;
  753. }
  754. INIT_LIST_HEAD(&hub->event_list);
  755. hub->intfdev = &intf->dev;
  756. hub->hdev = hdev;
  757. INIT_WORK(&hub->leds, led_work, hub);
  758. usb_set_intfdata (intf, hub);
  759. if (hdev->speed == USB_SPEED_HIGH)
  760. highspeed_hubs++;
  761. if (hub_configure(hub, endpoint) >= 0)
  762. return 0;
  763. hub_disconnect (intf);
  764. return -ENODEV;
  765. }
  766. static int
  767. hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
  768. {
  769. struct usb_device *hdev = interface_to_usbdev (intf);
  770. /* assert ifno == 0 (part of hub spec) */
  771. switch (code) {
  772. case USBDEVFS_HUB_PORTINFO: {
  773. struct usbdevfs_hub_portinfo *info = user_data;
  774. int i;
  775. spin_lock_irq(&device_state_lock);
  776. if (hdev->devnum <= 0)
  777. info->nports = 0;
  778. else {
  779. info->nports = hdev->maxchild;
  780. for (i = 0; i < info->nports; i++) {
  781. if (hdev->children[i] == NULL)
  782. info->port[i] = 0;
  783. else
  784. info->port[i] =
  785. hdev->children[i]->devnum;
  786. }
  787. }
  788. spin_unlock_irq(&device_state_lock);
  789. return info->nports + 1;
  790. }
  791. default:
  792. return -ENOSYS;
  793. }
  794. }
  795. /* grab device/port lock, returning index of that port (zero based).
  796. * protects the upstream link used by this device from concurrent
  797. * tree operations like suspend, resume, reset, and disconnect, which
  798. * apply to everything downstream of a given port.
  799. */
  800. static int locktree(struct usb_device *udev)
  801. {
  802. int t;
  803. struct usb_device *hdev;
  804. if (!udev)
  805. return -ENODEV;
  806. /* root hub is always the first lock in the series */
  807. hdev = udev->parent;
  808. if (!hdev) {
  809. usb_lock_device(udev);
  810. return 0;
  811. }
  812. /* on the path from root to us, lock everything from
  813. * top down, dropping parent locks when not needed
  814. */
  815. t = locktree(hdev);
  816. if (t < 0)
  817. return t;
  818. /* everything is fail-fast once disconnect
  819. * processing starts
  820. */
  821. if (udev->state == USB_STATE_NOTATTACHED) {
  822. usb_unlock_device(hdev);
  823. return -ENODEV;
  824. }
  825. /* when everyone grabs locks top->bottom,
  826. * non-overlapping work may be concurrent
  827. */
  828. usb_lock_device(udev);
  829. usb_unlock_device(hdev);
  830. return udev->portnum;
  831. }
  832. static void recursively_mark_NOTATTACHED(struct usb_device *udev)
  833. {
  834. int i;
  835. for (i = 0; i < udev->maxchild; ++i) {
  836. if (udev->children[i])
  837. recursively_mark_NOTATTACHED(udev->children[i]);
  838. }
  839. udev->state = USB_STATE_NOTATTACHED;
  840. }
  841. /**
  842. * usb_set_device_state - change a device's current state (usbcore, hcds)
  843. * @udev: pointer to device whose state should be changed
  844. * @new_state: new state value to be stored
  845. *
  846. * udev->state is _not_ fully protected by the device lock. Although
  847. * most transitions are made only while holding the lock, the state can
  848. * can change to USB_STATE_NOTATTACHED at almost any time. This
  849. * is so that devices can be marked as disconnected as soon as possible,
  850. * without having to wait for any semaphores to be released. As a result,
  851. * all changes to any device's state must be protected by the
  852. * device_state_lock spinlock.
  853. *
  854. * Once a device has been added to the device tree, all changes to its state
  855. * should be made using this routine. The state should _not_ be set directly.
  856. *
  857. * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
  858. * Otherwise udev->state is set to new_state, and if new_state is
  859. * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
  860. * to USB_STATE_NOTATTACHED.
  861. */
  862. void usb_set_device_state(struct usb_device *udev,
  863. enum usb_device_state new_state)
  864. {
  865. unsigned long flags;
  866. spin_lock_irqsave(&device_state_lock, flags);
  867. if (udev->state == USB_STATE_NOTATTACHED)
  868. ; /* do nothing */
  869. else if (new_state != USB_STATE_NOTATTACHED) {
  870. udev->state = new_state;
  871. /* root hub wakeup capabilities are managed out-of-band
  872. * and may involve silicon errata ... ignore them here.
  873. */
  874. if (udev->parent) {
  875. if (new_state == USB_STATE_CONFIGURED)
  876. device_init_wakeup(&udev->dev,
  877. (udev->actconfig->desc.bmAttributes
  878. & USB_CONFIG_ATT_WAKEUP));
  879. else if (new_state != USB_STATE_SUSPENDED)
  880. device_init_wakeup(&udev->dev, 0);
  881. }
  882. } else
  883. recursively_mark_NOTATTACHED(udev);
  884. spin_unlock_irqrestore(&device_state_lock, flags);
  885. }
  886. EXPORT_SYMBOL(usb_set_device_state);
  887. #ifdef CONFIG_PM
  888. /**
  889. * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
  890. * @rhdev: struct usb_device for the root hub
  891. *
  892. * The USB host controller driver calls this function when its root hub
  893. * is resumed and Vbus power has been interrupted or the controller
  894. * has been reset. The routine marks all the children of the root hub
  895. * as NOTATTACHED and marks logical connect-change events on their ports.
  896. */
  897. void usb_root_hub_lost_power(struct usb_device *rhdev)
  898. {
  899. struct usb_hub *hub;
  900. int port1;
  901. unsigned long flags;
  902. dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
  903. spin_lock_irqsave(&device_state_lock, flags);
  904. hub = hdev_to_hub(rhdev);
  905. for (port1 = 1; port1 <= rhdev->maxchild; ++port1) {
  906. if (rhdev->children[port1 - 1]) {
  907. recursively_mark_NOTATTACHED(
  908. rhdev->children[port1 - 1]);
  909. set_bit(port1, hub->change_bits);
  910. }
  911. }
  912. spin_unlock_irqrestore(&device_state_lock, flags);
  913. }
  914. EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
  915. #endif
  916. static void choose_address(struct usb_device *udev)
  917. {
  918. int devnum;
  919. struct usb_bus *bus = udev->bus;
  920. /* If khubd ever becomes multithreaded, this will need a lock */
  921. /* Try to allocate the next devnum beginning at bus->devnum_next. */
  922. devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
  923. bus->devnum_next);
  924. if (devnum >= 128)
  925. devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
  926. bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
  927. if (devnum < 128) {
  928. set_bit(devnum, bus->devmap.devicemap);
  929. udev->devnum = devnum;
  930. }
  931. }
  932. static void release_address(struct usb_device *udev)
  933. {
  934. if (udev->devnum > 0) {
  935. clear_bit(udev->devnum, udev->bus->devmap.devicemap);
  936. udev->devnum = -1;
  937. }
  938. }
  939. /**
  940. * usb_disconnect - disconnect a device (usbcore-internal)
  941. * @pdev: pointer to device being disconnected
  942. * Context: !in_interrupt ()
  943. *
  944. * Something got disconnected. Get rid of it and all of its children.
  945. *
  946. * If *pdev is a normal device then the parent hub must already be locked.
  947. * If *pdev is a root hub then this routine will acquire the
  948. * usb_bus_list_lock on behalf of the caller.
  949. *
  950. * Only hub drivers (including virtual root hub drivers for host
  951. * controllers) should ever call this.
  952. *
  953. * This call is synchronous, and may not be used in an interrupt context.
  954. */
  955. void usb_disconnect(struct usb_device **pdev)
  956. {
  957. struct usb_device *udev = *pdev;
  958. int i;
  959. if (!udev) {
  960. pr_debug ("%s nodev\n", __FUNCTION__);
  961. return;
  962. }
  963. /* mark the device as inactive, so any further urb submissions for
  964. * this device (and any of its children) will fail immediately.
  965. * this quiesces everyting except pending urbs.
  966. */
  967. usb_set_device_state(udev, USB_STATE_NOTATTACHED);
  968. dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
  969. usb_lock_device(udev);
  970. /* Free up all the children before we remove this device */
  971. for (i = 0; i < USB_MAXCHILDREN; i++) {
  972. if (udev->children[i])
  973. usb_disconnect(&udev->children[i]);
  974. }
  975. /* deallocate hcd/hardware state ... nuking all pending urbs and
  976. * cleaning up all state associated with the current configuration
  977. * so that the hardware is now fully quiesced.
  978. */
  979. usb_disable_device(udev, 0);
  980. usb_notify_remove_device(udev);
  981. /* Free the device number, remove the /proc/bus/usb entry and
  982. * the sysfs attributes, and delete the parent's children[]
  983. * (or root_hub) pointer.
  984. */
  985. dev_dbg (&udev->dev, "unregistering device\n");
  986. release_address(udev);
  987. usb_remove_sysfs_dev_files(udev);
  988. /* Avoid races with recursively_mark_NOTATTACHED() */
  989. spin_lock_irq(&device_state_lock);
  990. *pdev = NULL;
  991. spin_unlock_irq(&device_state_lock);
  992. usb_unlock_device(udev);
  993. device_unregister(&udev->dev);
  994. }
  995. static inline const char *plural(int n)
  996. {
  997. return (n == 1 ? "" : "s");
  998. }
  999. static int choose_configuration(struct usb_device *udev)
  1000. {
  1001. int i;
  1002. u16 devstatus;
  1003. int bus_powered;
  1004. int num_configs;
  1005. struct usb_host_config *c, *best;
  1006. /* If this fails, assume the device is bus-powered */
  1007. devstatus = 0;
  1008. usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
  1009. le16_to_cpus(&devstatus);
  1010. bus_powered = ((devstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0);
  1011. dev_dbg(&udev->dev, "device is %s-powered\n",
  1012. bus_powered ? "bus" : "self");
  1013. best = NULL;
  1014. c = udev->config;
  1015. num_configs = udev->descriptor.bNumConfigurations;
  1016. for (i = 0; i < num_configs; (i++, c++)) {
  1017. struct usb_interface_descriptor *desc = NULL;
  1018. /* It's possible that a config has no interfaces! */
  1019. if (c->desc.bNumInterfaces > 0)
  1020. desc = &c->intf_cache[0]->altsetting->desc;
  1021. /*
  1022. * HP's USB bus-powered keyboard has only one configuration
  1023. * and it claims to be self-powered; other devices may have
  1024. * similar errors in their descriptors. If the next test
  1025. * were allowed to execute, such configurations would always
  1026. * be rejected and the devices would not work as expected.
  1027. */
  1028. #if 0
  1029. /* Rule out self-powered configs for a bus-powered device */
  1030. if (bus_powered && (c->desc.bmAttributes &
  1031. USB_CONFIG_ATT_SELFPOWER))
  1032. continue;
  1033. #endif
  1034. /*
  1035. * The next test may not be as effective as it should be.
  1036. * Some hubs have errors in their descriptor, claiming
  1037. * to be self-powered when they are really bus-powered.
  1038. * We will overestimate the amount of current such hubs
  1039. * make available for each port.
  1040. *
  1041. * This is a fairly benign sort of failure. It won't
  1042. * cause us to reject configurations that we should have
  1043. * accepted.
  1044. */
  1045. /* Rule out configs that draw too much bus current */
  1046. if (c->desc.bMaxPower * 2 > udev->bus_mA)
  1047. continue;
  1048. /* If the first config's first interface is COMM/2/0xff
  1049. * (MSFT RNDIS), rule it out unless Linux has host-side
  1050. * RNDIS support. */
  1051. if (i == 0 && desc
  1052. && desc->bInterfaceClass == USB_CLASS_COMM
  1053. && desc->bInterfaceSubClass == 2
  1054. && desc->bInterfaceProtocol == 0xff) {
  1055. #ifndef CONFIG_USB_NET_RNDIS
  1056. continue;
  1057. #else
  1058. best = c;
  1059. #endif
  1060. }
  1061. /* From the remaining configs, choose the first one whose
  1062. * first interface is for a non-vendor-specific class.
  1063. * Reason: Linux is more likely to have a class driver
  1064. * than a vendor-specific driver. */
  1065. else if (udev->descriptor.bDeviceClass !=
  1066. USB_CLASS_VENDOR_SPEC &&
  1067. (!desc || desc->bInterfaceClass !=
  1068. USB_CLASS_VENDOR_SPEC)) {
  1069. best = c;
  1070. break;
  1071. }
  1072. /* If all the remaining configs are vendor-specific,
  1073. * choose the first one. */
  1074. else if (!best)
  1075. best = c;
  1076. }
  1077. if (best) {
  1078. i = best->desc.bConfigurationValue;
  1079. dev_info(&udev->dev,
  1080. "configuration #%d chosen from %d choice%s\n",
  1081. i, num_configs, plural(num_configs));
  1082. } else {
  1083. i = -1;
  1084. dev_warn(&udev->dev,
  1085. "no configuration chosen from %d choice%s\n",
  1086. num_configs, plural(num_configs));
  1087. }
  1088. return i;
  1089. }
  1090. #ifdef DEBUG
  1091. static void show_string(struct usb_device *udev, char *id, char *string)
  1092. {
  1093. if (!string)
  1094. return;
  1095. dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
  1096. }
  1097. #else
  1098. static inline void show_string(struct usb_device *udev, char *id, char *string)
  1099. {}
  1100. #endif
  1101. #ifdef CONFIG_USB_OTG
  1102. #include "otg_whitelist.h"
  1103. #endif
  1104. /**
  1105. * usb_new_device - perform initial device setup (usbcore-internal)
  1106. * @udev: newly addressed device (in ADDRESS state)
  1107. *
  1108. * This is called with devices which have been enumerated, but not yet
  1109. * configured. The device descriptor is available, but not descriptors
  1110. * for any device configuration. The caller must have locked either
  1111. * the parent hub (if udev is a normal device) or else the
  1112. * usb_bus_list_lock (if udev is a root hub). The parent's pointer to
  1113. * udev has already been installed, but udev is not yet visible through
  1114. * sysfs or other filesystem code.
  1115. *
  1116. * Returns 0 for success (device is configured and listed, with its
  1117. * interfaces, in sysfs); else a negative errno value.
  1118. *
  1119. * This call is synchronous, and may not be used in an interrupt context.
  1120. *
  1121. * Only the hub driver or root-hub registrar should ever call this.
  1122. */
  1123. int usb_new_device(struct usb_device *udev)
  1124. {
  1125. int err;
  1126. int c;
  1127. err = usb_get_configuration(udev);
  1128. if (err < 0) {
  1129. dev_err(&udev->dev, "can't read configurations, error %d\n",
  1130. err);
  1131. goto fail;
  1132. }
  1133. /* read the standard strings and cache them if present */
  1134. udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
  1135. udev->manufacturer = usb_cache_string(udev,
  1136. udev->descriptor.iManufacturer);
  1137. udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
  1138. /* Tell the world! */
  1139. dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
  1140. "SerialNumber=%d\n",
  1141. udev->descriptor.iManufacturer,
  1142. udev->descriptor.iProduct,
  1143. udev->descriptor.iSerialNumber);
  1144. show_string(udev, "Product", udev->product);
  1145. show_string(udev, "Manufacturer", udev->manufacturer);
  1146. show_string(udev, "SerialNumber", udev->serial);
  1147. #ifdef CONFIG_USB_OTG
  1148. /*
  1149. * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
  1150. * to wake us after we've powered off VBUS; and HNP, switching roles
  1151. * "host" to "peripheral". The OTG descriptor helps figure this out.
  1152. */
  1153. if (!udev->bus->is_b_host
  1154. && udev->config
  1155. && udev->parent == udev->bus->root_hub) {
  1156. struct usb_otg_descriptor *desc = 0;
  1157. struct usb_bus *bus = udev->bus;
  1158. /* descriptor may appear anywhere in config */
  1159. if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
  1160. le16_to_cpu(udev->config[0].desc.wTotalLength),
  1161. USB_DT_OTG, (void **) &desc) == 0) {
  1162. if (desc->bmAttributes & USB_OTG_HNP) {
  1163. unsigned port1 = udev->portnum;
  1164. struct usb_device *root = udev->parent;
  1165. dev_info(&udev->dev,
  1166. "Dual-Role OTG device on %sHNP port\n",
  1167. (port1 == bus->otg_port)
  1168. ? "" : "non-");
  1169. /* enable HNP before suspend, it's simpler */
  1170. if (port1 == bus->otg_port)
  1171. bus->b_hnp_enable = 1;
  1172. err = usb_control_msg(udev,
  1173. usb_sndctrlpipe(udev, 0),
  1174. USB_REQ_SET_FEATURE, 0,
  1175. bus->b_hnp_enable
  1176. ? USB_DEVICE_B_HNP_ENABLE
  1177. : USB_DEVICE_A_ALT_HNP_SUPPORT,
  1178. 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
  1179. if (err < 0) {
  1180. /* OTG MESSAGE: report errors here,
  1181. * customize to match your product.
  1182. */
  1183. dev_info(&udev->dev,
  1184. "can't set HNP mode; %d\n",
  1185. err);
  1186. bus->b_hnp_enable = 0;
  1187. }
  1188. }
  1189. }
  1190. }
  1191. if (!is_targeted(udev)) {
  1192. /* Maybe it can talk to us, though we can't talk to it.
  1193. * (Includes HNP test device.)
  1194. */
  1195. if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
  1196. static int __usb_suspend_device(struct usb_device *,
  1197. int port1);
  1198. err = __usb_suspend_device(udev, udev->bus->otg_port);
  1199. if (err < 0)
  1200. dev_dbg(&udev->dev, "HNP fail, %d\n", err);
  1201. }
  1202. err = -ENODEV;
  1203. goto fail;
  1204. }
  1205. #endif
  1206. /* put device-specific files into sysfs */
  1207. err = device_add (&udev->dev);
  1208. if (err) {
  1209. dev_err(&udev->dev, "can't device_add, error %d\n", err);
  1210. goto fail;
  1211. }
  1212. usb_create_sysfs_dev_files (udev);
  1213. usb_lock_device(udev);
  1214. /* choose and set the configuration. that registers the interfaces
  1215. * with the driver core, and lets usb device drivers bind to them.
  1216. */
  1217. c = choose_configuration(udev);
  1218. if (c >= 0) {
  1219. err = usb_set_configuration(udev, c);
  1220. if (err) {
  1221. dev_err(&udev->dev, "can't set config #%d, error %d\n",
  1222. c, err);
  1223. /* This need not be fatal. The user can try to
  1224. * set other configurations. */
  1225. }
  1226. }
  1227. /* USB device state == configured ... usable */
  1228. usb_notify_add_device(udev);
  1229. usb_unlock_device(udev);
  1230. return 0;
  1231. fail:
  1232. usb_set_device_state(udev, USB_STATE_NOTATTACHED);
  1233. return err;
  1234. }
  1235. static int hub_port_status(struct usb_hub *hub, int port1,
  1236. u16 *status, u16 *change)
  1237. {
  1238. int ret;
  1239. ret = get_port_status(hub->hdev, port1, &hub->status->port);
  1240. if (ret < 0)
  1241. dev_err (hub->intfdev,
  1242. "%s failed (err = %d)\n", __FUNCTION__, ret);
  1243. else {
  1244. *status = le16_to_cpu(hub->status->port.wPortStatus);
  1245. *change = le16_to_cpu(hub->status->port.wPortChange);
  1246. ret = 0;
  1247. }
  1248. return ret;
  1249. }
  1250. #define PORT_RESET_TRIES 5
  1251. #define SET_ADDRESS_TRIES 2
  1252. #define GET_DESCRIPTOR_TRIES 2
  1253. #define SET_CONFIG_TRIES (2 * (use_both_schemes + 1))
  1254. #define USE_NEW_SCHEME(i) ((i) / 2 == old_scheme_first)
  1255. #define HUB_ROOT_RESET_TIME 50 /* times are in msec */
  1256. #define HUB_SHORT_RESET_TIME 10
  1257. #define HUB_LONG_RESET_TIME 200
  1258. #define HUB_RESET_TIMEOUT 500
  1259. static int hub_port_wait_reset(struct usb_hub *hub, int port1,
  1260. struct usb_device *udev, unsigned int delay)
  1261. {
  1262. int delay_time, ret;
  1263. u16 portstatus;
  1264. u16 portchange;
  1265. for (delay_time = 0;
  1266. delay_time < HUB_RESET_TIMEOUT;
  1267. delay_time += delay) {
  1268. /* wait to give the device a chance to reset */
  1269. msleep(delay);
  1270. /* read and decode port status */
  1271. ret = hub_port_status(hub, port1, &portstatus, &portchange);
  1272. if (ret < 0)
  1273. return ret;
  1274. /* Device went away? */
  1275. if (!(portstatus & USB_PORT_STAT_CONNECTION))
  1276. return -ENOTCONN;
  1277. /* bomb out completely if something weird happened */
  1278. if ((portchange & USB_PORT_STAT_C_CONNECTION))
  1279. return -EINVAL;
  1280. /* if we`ve finished resetting, then break out of the loop */
  1281. if (!(portstatus & USB_PORT_STAT_RESET) &&
  1282. (portstatus & USB_PORT_STAT_ENABLE)) {
  1283. if (portstatus & USB_PORT_STAT_HIGH_SPEED)
  1284. udev->speed = USB_SPEED_HIGH;
  1285. else if (portstatus & USB_PORT_STAT_LOW_SPEED)
  1286. udev->speed = USB_SPEED_LOW;
  1287. else
  1288. udev->speed = USB_SPEED_FULL;
  1289. return 0;
  1290. }
  1291. /* switch to the long delay after two short delay failures */
  1292. if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
  1293. delay = HUB_LONG_RESET_TIME;
  1294. dev_dbg (hub->intfdev,
  1295. "port %d not reset yet, waiting %dms\n",
  1296. port1, delay);
  1297. }
  1298. return -EBUSY;
  1299. }
  1300. static int hub_port_reset(struct usb_hub *hub, int port1,
  1301. struct usb_device *udev, unsigned int delay)
  1302. {
  1303. int i, status;
  1304. /* Reset the port */
  1305. for (i = 0; i < PORT_RESET_TRIES; i++) {
  1306. status = set_port_feature(hub->hdev,
  1307. port1, USB_PORT_FEAT_RESET);
  1308. if (status)
  1309. dev_err(hub->intfdev,
  1310. "cannot reset port %d (err = %d)\n",
  1311. port1, status);
  1312. else {
  1313. status = hub_port_wait_reset(hub, port1, udev, delay);
  1314. if (status && status != -ENOTCONN)
  1315. dev_dbg(hub->intfdev,
  1316. "port_wait_reset: err = %d\n",
  1317. status);
  1318. }
  1319. /* return on disconnect or reset */
  1320. switch (status) {
  1321. case 0:
  1322. /* TRSTRCY = 10 ms; plus some extra */
  1323. msleep(10 + 40);
  1324. /* FALL THROUGH */
  1325. case -ENOTCONN:
  1326. case -ENODEV:
  1327. clear_port_feature(hub->hdev,
  1328. port1, USB_PORT_FEAT_C_RESET);
  1329. /* FIXME need disconnect() for NOTATTACHED device */
  1330. usb_set_device_state(udev, status
  1331. ? USB_STATE_NOTATTACHED
  1332. : USB_STATE_DEFAULT);
  1333. return status;
  1334. }
  1335. dev_dbg (hub->intfdev,
  1336. "port %d not enabled, trying reset again...\n",
  1337. port1);
  1338. delay = HUB_LONG_RESET_TIME;
  1339. }
  1340. dev_err (hub->intfdev,
  1341. "Cannot enable port %i. Maybe the USB cable is bad?\n",
  1342. port1);
  1343. return status;
  1344. }
  1345. /*
  1346. * Disable a port and mark a logical connnect-change event, so that some
  1347. * time later khubd will disconnect() any existing usb_device on the port
  1348. * and will re-enumerate if there actually is a device attached.
  1349. */
  1350. static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
  1351. {
  1352. dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
  1353. hub_port_disable(hub, port1, 1);
  1354. /* FIXME let caller ask to power down the port:
  1355. * - some devices won't enumerate without a VBUS power cycle
  1356. * - SRP saves power that way
  1357. * - ... new call, TBD ...
  1358. * That's easy if this hub can switch power per-port, and
  1359. * khubd reactivates the port later (timer, SRP, etc).
  1360. * Powerdown must be optional, because of reset/DFU.
  1361. */
  1362. set_bit(port1, hub->change_bits);
  1363. kick_khubd(hub);
  1364. }
  1365. #ifdef CONFIG_USB_SUSPEND
  1366. /*
  1367. * Selective port suspend reduces power; most suspended devices draw
  1368. * less than 500 uA. It's also used in OTG, along with remote wakeup.
  1369. * All devices below the suspended port are also suspended.
  1370. *
  1371. * Devices leave suspend state when the host wakes them up. Some devices
  1372. * also support "remote wakeup", where the device can activate the USB
  1373. * tree above them to deliver data, such as a keypress or packet. In
  1374. * some cases, this wakes the USB host.
  1375. */
  1376. static int hub_port_suspend(struct usb_hub *hub, int port1,
  1377. struct usb_device *udev)
  1378. {
  1379. int status;
  1380. // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
  1381. /* enable remote wakeup when appropriate; this lets the device
  1382. * wake up the upstream hub (including maybe the root hub).
  1383. *
  1384. * NOTE: OTG devices may issue remote wakeup (or SRP) even when
  1385. * we don't explicitly enable it here.
  1386. */
  1387. if (device_may_wakeup(&udev->dev)) {
  1388. status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
  1389. USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
  1390. USB_DEVICE_REMOTE_WAKEUP, 0,
  1391. NULL, 0,
  1392. USB_CTRL_SET_TIMEOUT);
  1393. if (status)
  1394. dev_dbg(&udev->dev,
  1395. "won't remote wakeup, status %d\n",
  1396. status);
  1397. }
  1398. /* see 7.1.7.6 */
  1399. status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
  1400. if (status) {
  1401. dev_dbg(hub->intfdev,
  1402. "can't suspend port %d, status %d\n",
  1403. port1, status);
  1404. /* paranoia: "should not happen" */
  1405. (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
  1406. USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
  1407. USB_DEVICE_REMOTE_WAKEUP, 0,
  1408. NULL, 0,
  1409. USB_CTRL_SET_TIMEOUT);
  1410. } else {
  1411. /* device has up to 10 msec to fully suspend */
  1412. dev_dbg(&udev->dev, "usb suspend\n");
  1413. usb_set_device_state(udev, USB_STATE_SUSPENDED);
  1414. msleep(10);
  1415. }
  1416. return status;
  1417. }
  1418. /*
  1419. * Devices on USB hub ports have only one "suspend" state, corresponding
  1420. * to ACPI D2, "may cause the device to lose some context".
  1421. * State transitions include:
  1422. *
  1423. * - suspend, resume ... when the VBUS power link stays live
  1424. * - suspend, disconnect ... VBUS lost
  1425. *
  1426. * Once VBUS drop breaks the circuit, the port it's using has to go through
  1427. * normal re-enumeration procedures, starting with enabling VBUS power.
  1428. * Other than re-initializing the hub (plug/unplug, except for root hubs),
  1429. * Linux (2.6) currently has NO mechanisms to initiate that: no khubd
  1430. * timer, no SRP, no requests through sysfs.
  1431. *
  1432. * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
  1433. * the root hub for their bus goes into global suspend ... so we don't
  1434. * (falsely) update the device power state to say it suspended.
  1435. */
  1436. static int __usb_suspend_device (struct usb_device *udev, int port1)
  1437. {
  1438. int status = 0;
  1439. /* caller owns the udev device lock */
  1440. if (port1 < 0)
  1441. return port1;
  1442. if (udev->state == USB_STATE_SUSPENDED
  1443. || udev->state == USB_STATE_NOTATTACHED) {
  1444. return 0;
  1445. }
  1446. /* all interfaces must already be suspended */
  1447. if (udev->actconfig) {
  1448. int i;
  1449. for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
  1450. struct usb_interface *intf;
  1451. intf = udev->actconfig->interface[i];
  1452. if (is_active(intf)) {
  1453. dev_dbg(&intf->dev, "nyet suspended\n");
  1454. return -EBUSY;
  1455. }
  1456. }
  1457. }
  1458. /* we only change a device's upstream USB link.
  1459. * root hubs have no upstream USB link.
  1460. */
  1461. if (udev->parent)
  1462. status = hub_port_suspend(hdev_to_hub(udev->parent), port1,
  1463. udev);
  1464. if (status == 0)
  1465. udev->dev.power.power_state = PMSG_SUSPEND;
  1466. return status;
  1467. }
  1468. #endif
  1469. /*
  1470. * usb_suspend_device - suspend a usb device
  1471. * @udev: device that's no longer in active use
  1472. * Context: must be able to sleep; device not locked; pm locks held
  1473. *
  1474. * Suspends a USB device that isn't in active use, conserving power.
  1475. * Devices may wake out of a suspend, if anything important happens,
  1476. * using the remote wakeup mechanism. They may also be taken out of
  1477. * suspend by the host, using usb_resume_device(). It's also routine
  1478. * to disconnect devices while they are suspended.
  1479. *
  1480. * This only affects the USB hardware for a device; its interfaces
  1481. * (and, for hubs, child devices) must already have been suspended.
  1482. *
  1483. * Suspending OTG devices may trigger HNP, if that's been enabled
  1484. * between a pair of dual-role devices. That will change roles, such
  1485. * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
  1486. *
  1487. * Returns 0 on success, else negative errno.
  1488. */
  1489. int usb_suspend_device(struct usb_device *udev)
  1490. {
  1491. #ifdef CONFIG_USB_SUSPEND
  1492. if (udev->state == USB_STATE_NOTATTACHED)
  1493. return -ENODEV;
  1494. return __usb_suspend_device(udev, udev->portnum);
  1495. #else
  1496. /* NOTE: udev->state unchanged, it's not lying ... */
  1497. udev->dev.power.power_state = PMSG_SUSPEND;
  1498. return 0;
  1499. #endif
  1500. }
  1501. /*
  1502. * If the USB "suspend" state is in use (rather than "global suspend"),
  1503. * many devices will be individually taken out of suspend state using
  1504. * special" resume" signaling. These routines kick in shortly after
  1505. * hardware resume signaling is finished, either because of selective
  1506. * resume (by host) or remote wakeup (by device) ... now see what changed
  1507. * in the tree that's rooted at this device.
  1508. */
  1509. static int finish_device_resume(struct usb_device *udev)
  1510. {
  1511. int status;
  1512. u16 devstatus;
  1513. /* caller owns the udev device lock */
  1514. dev_dbg(&udev->dev, "finish resume\n");
  1515. /* usb ch9 identifies four variants of SUSPENDED, based on what
  1516. * state the device resumes to. Linux currently won't see the
  1517. * first two on the host side; they'd be inside hub_port_init()
  1518. * during many timeouts, but khubd can't suspend until later.
  1519. */
  1520. usb_set_device_state(udev, udev->actconfig
  1521. ? USB_STATE_CONFIGURED
  1522. : USB_STATE_ADDRESS);
  1523. udev->dev.power.power_state = PMSG_ON;
  1524. /* 10.5.4.5 says be sure devices in the tree are still there.
  1525. * For now let's assume the device didn't go crazy on resume,
  1526. * and device drivers will know about any resume quirks.
  1527. */
  1528. status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
  1529. if (status < 2)
  1530. dev_dbg(&udev->dev,
  1531. "gone after usb resume? status %d\n",
  1532. status);
  1533. else if (udev->actconfig) {
  1534. unsigned i;
  1535. int (*resume)(struct device *);
  1536. le16_to_cpus(&devstatus);
  1537. if ((devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP))
  1538. && udev->parent) {
  1539. status = usb_control_msg(udev,
  1540. usb_sndctrlpipe(udev, 0),
  1541. USB_REQ_CLEAR_FEATURE,
  1542. USB_RECIP_DEVICE,
  1543. USB_DEVICE_REMOTE_WAKEUP, 0,
  1544. NULL, 0,
  1545. USB_CTRL_SET_TIMEOUT);
  1546. if (status) {
  1547. dev_dbg(&udev->dev, "disable remote "
  1548. "wakeup, status %d\n", status);
  1549. status = 0;
  1550. }
  1551. }
  1552. /* resume interface drivers; if this is a hub, it
  1553. * may have a child resume event to deal with soon
  1554. */
  1555. resume = udev->dev.bus->resume;
  1556. for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
  1557. struct device *dev =
  1558. &udev->actconfig->interface[i]->dev;
  1559. down(&dev->sem);
  1560. (void) resume(dev);
  1561. up(&dev->sem);
  1562. }
  1563. status = 0;
  1564. } else if (udev->devnum <= 0) {
  1565. dev_dbg(&udev->dev, "bogus resume!\n");
  1566. status = -EINVAL;
  1567. }
  1568. return status;
  1569. }
  1570. #ifdef CONFIG_USB_SUSPEND
  1571. static int
  1572. hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
  1573. {
  1574. int status;
  1575. // dev_dbg(hub->intfdev, "resume port %d\n", port1);
  1576. /* see 7.1.7.7; affects power usage, but not budgeting */
  1577. status = clear_port_feature(hub->hdev,
  1578. port1, USB_PORT_FEAT_SUSPEND);
  1579. if (status) {
  1580. dev_dbg(hub->intfdev,
  1581. "can't resume port %d, status %d\n",
  1582. port1, status);
  1583. } else {
  1584. u16 devstatus;
  1585. u16 portchange;
  1586. /* drive resume for at least 20 msec */
  1587. if (udev)
  1588. dev_dbg(&udev->dev, "RESUME\n");
  1589. msleep(25);
  1590. #define LIVE_FLAGS ( USB_PORT_STAT_POWER \
  1591. | USB_PORT_STAT_ENABLE \
  1592. | USB_PORT_STAT_CONNECTION)
  1593. /* Virtual root hubs can trigger on GET_PORT_STATUS to
  1594. * stop resume signaling. Then finish the resume
  1595. * sequence.
  1596. */
  1597. devstatus = portchange = 0;
  1598. status = hub_port_status(hub, port1,
  1599. &devstatus, &portchange);
  1600. if (status < 0
  1601. || (devstatus & LIVE_FLAGS) != LIVE_FLAGS
  1602. || (devstatus & USB_PORT_STAT_SUSPEND) != 0
  1603. ) {
  1604. dev_dbg(hub->intfdev,
  1605. "port %d status %04x.%04x after resume, %d\n",
  1606. port1, portchange, devstatus, status);
  1607. } else {
  1608. /* TRSMRCY = 10 msec */
  1609. msleep(10);
  1610. if (udev)
  1611. status = finish_device_resume(udev);
  1612. }
  1613. }
  1614. if (status < 0)
  1615. hub_port_logical_disconnect(hub, port1);
  1616. return status;
  1617. }
  1618. #endif
  1619. /*
  1620. * usb_resume_device - re-activate a suspended usb device
  1621. * @udev: device to re-activate
  1622. * Context: must be able to sleep; device not locked; pm locks held
  1623. *
  1624. * This will re-activate the suspended device, increasing power usage
  1625. * while letting drivers communicate again with its endpoints.
  1626. * USB resume explicitly guarantees that the power session between
  1627. * the host and the device is the same as it was when the device
  1628. * suspended.
  1629. *
  1630. * Returns 0 on success, else negative errno.
  1631. */
  1632. int usb_resume_device(struct usb_device *udev)
  1633. {
  1634. int status;
  1635. if (udev->state == USB_STATE_NOTATTACHED)
  1636. return -ENODEV;
  1637. /* selective resume of one downstream hub-to-device port */
  1638. if (udev->parent) {
  1639. #ifdef CONFIG_USB_SUSPEND
  1640. if (udev->state == USB_STATE_SUSPENDED) {
  1641. // NOTE swsusp may bork us, device state being wrong...
  1642. // NOTE this fails if parent is also suspended...
  1643. status = hub_port_resume(hdev_to_hub(udev->parent),
  1644. udev->portnum, udev);
  1645. } else
  1646. #endif
  1647. status = 0;
  1648. } else
  1649. status = finish_device_resume(udev);
  1650. if (status < 0)
  1651. dev_dbg(&udev->dev, "can't resume, status %d\n",
  1652. status);
  1653. /* rebind drivers that had no suspend() */
  1654. if (status == 0) {
  1655. usb_unlock_device(udev);
  1656. bus_rescan_devices(&usb_bus_type);
  1657. usb_lock_device(udev);
  1658. }
  1659. return status;
  1660. }
  1661. static int remote_wakeup(struct usb_device *udev)
  1662. {
  1663. int status = 0;
  1664. #ifdef CONFIG_USB_SUSPEND
  1665. /* don't repeat RESUME sequence if this device
  1666. * was already woken up by some other task
  1667. */
  1668. usb_lock_device(udev);
  1669. if (udev->state == USB_STATE_SUSPENDED) {
  1670. dev_dbg(&udev->dev, "RESUME (wakeup)\n");
  1671. /* TRSMRCY = 10 msec */
  1672. msleep(10);
  1673. status = finish_device_resume(udev);
  1674. }
  1675. usb_unlock_device(udev);
  1676. #endif
  1677. return status;
  1678. }
  1679. static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
  1680. {
  1681. struct usb_hub *hub = usb_get_intfdata (intf);
  1682. struct usb_device *hdev = hub->hdev;
  1683. unsigned port1;
  1684. /* fail if children aren't already suspended */
  1685. for (port1 = 1; port1 <= hdev->maxchild; port1++) {
  1686. struct usb_device *udev;
  1687. udev = hdev->children [port1-1];
  1688. if (udev && (udev->dev.power.power_state.event
  1689. == PM_EVENT_ON
  1690. #ifdef CONFIG_USB_SUSPEND
  1691. || udev->state != USB_STATE_SUSPENDED
  1692. #endif
  1693. )) {
  1694. dev_dbg(&intf->dev, "port %d nyet suspended\n", port1);
  1695. return -EBUSY;
  1696. }
  1697. }
  1698. /* "global suspend" of the downstream HC-to-USB interface */
  1699. if (!hdev->parent) {
  1700. struct usb_bus *bus = hdev->bus;
  1701. if (bus) {
  1702. int status = hcd_bus_suspend (bus);
  1703. if (status != 0) {
  1704. dev_dbg(&hdev->dev, "'global' suspend %d\n",
  1705. status);
  1706. return status;
  1707. }
  1708. } else
  1709. return -EOPNOTSUPP;
  1710. }
  1711. /* stop khubd and related activity */
  1712. hub_quiesce(hub);
  1713. return 0;
  1714. }
  1715. static int hub_resume(struct usb_interface *intf)
  1716. {
  1717. struct usb_device *hdev = interface_to_usbdev(intf);
  1718. struct usb_hub *hub = usb_get_intfdata (intf);
  1719. int status;
  1720. /* "global resume" of the downstream HC-to-USB interface */
  1721. if (!hdev->parent) {
  1722. struct usb_bus *bus = hdev->bus;
  1723. if (bus) {
  1724. status = hcd_bus_resume (bus);
  1725. if (status) {
  1726. dev_dbg(&intf->dev, "'global' resume %d\n",
  1727. status);
  1728. return status;
  1729. }
  1730. } else
  1731. return -EOPNOTSUPP;
  1732. if (status == 0) {
  1733. /* TRSMRCY = 10 msec */
  1734. msleep(10);
  1735. }
  1736. }
  1737. hub_activate(hub);
  1738. /* REVISIT: this recursion probably shouldn't exist. Remove
  1739. * this code sometime, after retesting with different root and
  1740. * external hubs.
  1741. */
  1742. #ifdef CONFIG_USB_SUSPEND
  1743. {
  1744. unsigned port1;
  1745. for (port1 = 1; port1 <= hdev->maxchild; port1++) {
  1746. struct usb_device *udev;
  1747. u16 portstat, portchange;
  1748. udev = hdev->children [port1-1];
  1749. status = hub_port_status(hub, port1, &portstat, &portchange);
  1750. if (status == 0) {
  1751. if (portchange & USB_PORT_STAT_C_SUSPEND) {
  1752. clear_port_feature(hdev, port1,
  1753. USB_PORT_FEAT_C_SUSPEND);
  1754. portchange &= ~USB_PORT_STAT_C_SUSPEND;
  1755. }
  1756. /* let khubd handle disconnects etc */
  1757. if (portchange)
  1758. continue;
  1759. }
  1760. if (!udev || status < 0)
  1761. continue;
  1762. usb_lock_device(udev);
  1763. if (portstat & USB_PORT_STAT_SUSPEND)
  1764. status = hub_port_resume(hub, port1, udev);
  1765. else {
  1766. status = finish_device_resume(udev);
  1767. if (status < 0) {
  1768. dev_dbg(&intf->dev, "resume port %d --> %d\n",
  1769. port1, status);
  1770. hub_port_logical_disconnect(hub, port1);
  1771. }
  1772. }
  1773. usb_unlock_device(udev);
  1774. }
  1775. }
  1776. #endif
  1777. return 0;
  1778. }
  1779. void usb_suspend_root_hub(struct usb_device *hdev)
  1780. {
  1781. struct usb_hub *hub = hdev_to_hub(hdev);
  1782. /* This also makes any led blinker stop retriggering. We're called
  1783. * from irq, so the blinker might still be scheduled. Caller promises
  1784. * that the root hub status URB will be canceled.
  1785. */
  1786. __hub_quiesce(hub);
  1787. mark_quiesced(to_usb_interface(hub->intfdev));
  1788. }
  1789. void usb_resume_root_hub(struct usb_device *hdev)
  1790. {
  1791. struct usb_hub *hub = hdev_to_hub(hdev);
  1792. hub->resume_root_hub = 1;
  1793. kick_khubd(hub);
  1794. }
  1795. /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
  1796. *
  1797. * Between connect detection and reset signaling there must be a delay
  1798. * of 100ms at least for debounce and power-settling. The corresponding
  1799. * timer shall restart whenever the downstream port detects a disconnect.
  1800. *
  1801. * Apparently there are some bluetooth and irda-dongles and a number of
  1802. * low-speed devices for which this debounce period may last over a second.
  1803. * Not covered by the spec - but easy to deal with.
  1804. *
  1805. * This implementation uses a 1500ms total debounce timeout; if the
  1806. * connection isn't stable by then it returns -ETIMEDOUT. It checks
  1807. * every 25ms for transient disconnects. When the port status has been
  1808. * unchanged for 100ms it returns the port status.
  1809. */
  1810. #define HUB_DEBOUNCE_TIMEOUT 1500
  1811. #define HUB_DEBOUNCE_STEP 25
  1812. #define HUB_DEBOUNCE_STABLE 100
  1813. static int hub_port_debounce(struct usb_hub *hub, int port1)
  1814. {
  1815. int ret;
  1816. int total_time, stable_time = 0;
  1817. u16 portchange, portstatus;
  1818. unsigned connection = 0xffff;
  1819. for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
  1820. ret = hub_port_status(hub, port1, &portstatus, &portchange);
  1821. if (ret < 0)
  1822. return ret;
  1823. if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
  1824. (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
  1825. stable_time += HUB_DEBOUNCE_STEP;
  1826. if (stable_time >= HUB_DEBOUNCE_STABLE)
  1827. break;
  1828. } else {
  1829. stable_time = 0;
  1830. connection = portstatus & USB_PORT_STAT_CONNECTION;
  1831. }
  1832. if (portchange & USB_PORT_STAT_C_CONNECTION) {
  1833. clear_port_feature(hub->hdev, port1,
  1834. USB_PORT_FEAT_C_CONNECTION);
  1835. }
  1836. if (total_time >= HUB_DEBOUNCE_TIMEOUT)
  1837. break;
  1838. msleep(HUB_DEBOUNCE_STEP);
  1839. }
  1840. dev_dbg (hub->intfdev,
  1841. "debounce: port %d: total %dms stable %dms status 0x%x\n",
  1842. port1, total_time, stable_time, portstatus);
  1843. if (stable_time < HUB_DEBOUNCE_STABLE)
  1844. return -ETIMEDOUT;
  1845. return portstatus;
  1846. }
  1847. static void ep0_reinit(struct usb_device *udev)
  1848. {
  1849. usb_disable_endpoint(udev, 0 + USB_DIR_IN);
  1850. usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
  1851. udev->ep_in[0] = udev->ep_out[0] = &udev->ep0;
  1852. }
  1853. #define usb_sndaddr0pipe() (PIPE_CONTROL << 30)
  1854. #define usb_rcvaddr0pipe() ((PIPE_CONTROL << 30) | USB_DIR_IN)
  1855. static int hub_set_address(struct usb_device *udev)
  1856. {
  1857. int retval;
  1858. if (udev->devnum == 0)
  1859. return -EINVAL;
  1860. if (udev->state == USB_STATE_ADDRESS)
  1861. return 0;
  1862. if (udev->state != USB_STATE_DEFAULT)
  1863. return -EINVAL;
  1864. retval = usb_control_msg(udev, usb_sndaddr0pipe(),
  1865. USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
  1866. NULL, 0, USB_CTRL_SET_TIMEOUT);
  1867. if (retval == 0) {
  1868. usb_set_device_state(udev, USB_STATE_ADDRESS);
  1869. ep0_reinit(udev);
  1870. }
  1871. return retval;
  1872. }
  1873. /* Reset device, (re)assign address, get device descriptor.
  1874. * Device connection must be stable, no more debouncing needed.
  1875. * Returns device in USB_STATE_ADDRESS, except on error.
  1876. *
  1877. * If this is called for an already-existing device (as part of
  1878. * usb_reset_device), the caller must own the device lock. For a
  1879. * newly detected device that is not accessible through any global
  1880. * pointers, it's not necessary to lock the device.
  1881. */
  1882. static int
  1883. hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
  1884. int retry_counter)
  1885. {
  1886. static DEFINE_MUTEX(usb_address0_mutex);
  1887. struct usb_device *hdev = hub->hdev;
  1888. int i, j, retval;
  1889. unsigned delay = HUB_SHORT_RESET_TIME;
  1890. enum usb_device_speed oldspeed = udev->speed;
  1891. /* root hub ports have a slightly longer reset period
  1892. * (from USB 2.0 spec, section 7.1.7.5)
  1893. */
  1894. if (!hdev->parent) {
  1895. delay = HUB_ROOT_RESET_TIME;
  1896. if (port1 == hdev->bus->otg_port)
  1897. hdev->bus->b_hnp_enable = 0;
  1898. }
  1899. /* Some low speed devices have problems with the quick delay, so */
  1900. /* be a bit pessimistic with those devices. RHbug #23670 */
  1901. if (oldspeed == USB_SPEED_LOW)
  1902. delay = HUB_LONG_RESET_TIME;
  1903. mutex_lock(&usb_address0_mutex);
  1904. /* Reset the device; full speed may morph to high speed */
  1905. retval = hub_port_reset(hub, port1, udev, delay);
  1906. if (retval < 0) /* error or disconnect */
  1907. goto fail;
  1908. /* success, speed is known */
  1909. retval = -ENODEV;
  1910. if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
  1911. dev_dbg(&udev->dev, "device reset changed speed!\n");
  1912. goto fail;
  1913. }
  1914. oldspeed = udev->speed;
  1915. /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
  1916. * it's fixed size except for full speed devices.
  1917. */
  1918. switch (udev->speed) {
  1919. case USB_SPEED_HIGH: /* fixed at 64 */
  1920. udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
  1921. break;
  1922. case USB_SPEED_FULL: /* 8, 16, 32, or 64 */
  1923. /* to determine the ep0 maxpacket size, try to read
  1924. * the device descriptor to get bMaxPacketSize0 and
  1925. * then correct our initial guess.
  1926. */
  1927. udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
  1928. break;
  1929. case USB_SPEED_LOW: /* fixed at 8 */
  1930. udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
  1931. break;
  1932. default:
  1933. goto fail;
  1934. }
  1935. dev_info (&udev->dev,
  1936. "%s %s speed USB device using %s and address %d\n",
  1937. (udev->config) ? "reset" : "new",
  1938. ({ char *speed; switch (udev->speed) {
  1939. case USB_SPEED_LOW: speed = "low"; break;
  1940. case USB_SPEED_FULL: speed = "full"; break;
  1941. case USB_SPEED_HIGH: speed = "high"; break;
  1942. default: speed = "?"; break;
  1943. }; speed;}),
  1944. udev->bus->controller->driver->name,
  1945. udev->devnum);
  1946. /* Set up TT records, if needed */
  1947. if (hdev->tt) {
  1948. udev->tt = hdev->tt;
  1949. udev->ttport = hdev->ttport;
  1950. } else if (udev->speed != USB_SPEED_HIGH
  1951. && hdev->speed == USB_SPEED_HIGH) {
  1952. udev->tt = &hub->tt;
  1953. udev->ttport = port1;
  1954. }
  1955. /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
  1956. * Because device hardware and firmware is sometimes buggy in
  1957. * this area, and this is how Linux has done it for ages.
  1958. * Change it cautiously.
  1959. *
  1960. * NOTE: If USE_NEW_SCHEME() is true we will start by issuing
  1961. * a 64-byte GET_DESCRIPTOR request. This is what Windows does,
  1962. * so it may help with some non-standards-compliant devices.
  1963. * Otherwise we start with SET_ADDRESS and then try to read the
  1964. * first 8 bytes of the device descriptor to get the ep0 maxpacket
  1965. * value.
  1966. */
  1967. for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
  1968. if (USE_NEW_SCHEME(retry_counter)) {
  1969. struct usb_device_descriptor *buf;
  1970. int r = 0;
  1971. #define GET_DESCRIPTOR_BUFSIZE 64
  1972. buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
  1973. if (!buf) {
  1974. retval = -ENOMEM;
  1975. continue;
  1976. }
  1977. /* Use a short timeout the first time through,
  1978. * so that recalcitrant full-speed devices with
  1979. * 8- or 16-byte ep0-maxpackets won't slow things
  1980. * down tremendously by NAKing the unexpectedly
  1981. * early status stage. Also, retry on all errors;
  1982. * some devices are flakey.
  1983. */
  1984. for (j = 0; j < 3; ++j) {
  1985. buf->bMaxPacketSize0 = 0;
  1986. r = usb_control_msg(udev, usb_rcvaddr0pipe(),
  1987. USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
  1988. USB_DT_DEVICE << 8, 0,
  1989. buf, GET_DESCRIPTOR_BUFSIZE,
  1990. (i ? USB_CTRL_GET_TIMEOUT : 1000));
  1991. switch (buf->bMaxPacketSize0) {
  1992. case 8: case 16: case 32: case 64:
  1993. if (buf->bDescriptorType ==
  1994. USB_DT_DEVICE) {
  1995. r = 0;
  1996. break;
  1997. }
  1998. /* FALL THROUGH */
  1999. default:
  2000. if (r == 0)
  2001. r = -EPROTO;
  2002. break;
  2003. }
  2004. if (r == 0)
  2005. break;
  2006. }
  2007. udev->descriptor.bMaxPacketSize0 =
  2008. buf->bMaxPacketSize0;
  2009. kfree(buf);
  2010. retval = hub_port_reset(hub, port1, udev, delay);
  2011. if (retval < 0) /* error or disconnect */
  2012. goto fail;
  2013. if (oldspeed != udev->speed) {
  2014. dev_dbg(&udev->dev,
  2015. "device reset changed speed!\n");
  2016. retval = -ENODEV;
  2017. goto fail;
  2018. }
  2019. if (r) {
  2020. dev_err(&udev->dev, "device descriptor "
  2021. "read/%s, error %d\n",
  2022. "64", r);
  2023. retval = -EMSGSIZE;
  2024. continue;
  2025. }
  2026. #undef GET_DESCRIPTOR_BUFSIZE
  2027. }
  2028. for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
  2029. retval = hub_set_address(udev);
  2030. if (retval >= 0)
  2031. break;
  2032. msleep(200);
  2033. }
  2034. if (retval < 0) {
  2035. dev_err(&udev->dev,
  2036. "device not accepting address %d, error %d\n",
  2037. udev->devnum, retval);
  2038. goto fail;
  2039. }
  2040. /* cope with hardware quirkiness:
  2041. * - let SET_ADDRESS settle, some device hardware wants it
  2042. * - read ep0 maxpacket even for high and low speed,
  2043. */
  2044. msleep(10);
  2045. if (USE_NEW_SCHEME(retry_counter))
  2046. break;
  2047. retval = usb_get_device_descriptor(udev, 8);
  2048. if (retval < 8) {
  2049. dev_err(&udev->dev, "device descriptor "
  2050. "read/%s, error %d\n",
  2051. "8", retval);
  2052. if (retval >= 0)
  2053. retval = -EMSGSIZE;
  2054. } else {
  2055. retval = 0;
  2056. break;
  2057. }
  2058. }
  2059. if (retval)
  2060. goto fail;
  2061. i = udev->descriptor.bMaxPacketSize0;
  2062. if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
  2063. if (udev->speed != USB_SPEED_FULL ||
  2064. !(i == 8 || i == 16 || i == 32 || i == 64)) {
  2065. dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
  2066. retval = -EMSGSIZE;
  2067. goto fail;
  2068. }
  2069. dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
  2070. udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
  2071. ep0_reinit(udev);
  2072. }
  2073. retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
  2074. if (retval < (signed)sizeof(udev->descriptor)) {
  2075. dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
  2076. "all", retval);
  2077. if (retval >= 0)
  2078. retval = -ENOMSG;
  2079. goto fail;
  2080. }
  2081. retval = 0;
  2082. fail:
  2083. if (retval)
  2084. hub_port_disable(hub, port1, 0);
  2085. mutex_unlock(&usb_address0_mutex);
  2086. return retval;
  2087. }
  2088. static void
  2089. check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
  2090. {
  2091. struct usb_qualifier_descriptor *qual;
  2092. int status;
  2093. qual = kmalloc (sizeof *qual, SLAB_KERNEL);
  2094. if (qual == NULL)
  2095. return;
  2096. status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
  2097. qual, sizeof *qual);
  2098. if (status == sizeof *qual) {
  2099. dev_info(&udev->dev, "not running at top speed; "
  2100. "connect to a high speed hub\n");
  2101. /* hub LEDs are probably harder to miss than syslog */
  2102. if (hub->has_indicators) {
  2103. hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
  2104. schedule_work (&hub->leds);
  2105. }
  2106. }
  2107. kfree(qual);
  2108. }
  2109. static unsigned
  2110. hub_power_remaining (struct usb_hub *hub)
  2111. {
  2112. struct usb_device *hdev = hub->hdev;
  2113. int remaining;
  2114. int port1;
  2115. if (!hub->limited_power)
  2116. return 0;
  2117. remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
  2118. for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
  2119. struct usb_device *udev = hdev->children[port1 - 1];
  2120. int delta;
  2121. if (!udev)
  2122. continue;
  2123. /* Unconfigured devices may not use more than 100mA,
  2124. * or 8mA for OTG ports */
  2125. if (udev->actconfig)
  2126. delta = udev->actconfig->desc.bMaxPower * 2;
  2127. else if (port1 != udev->bus->otg_port || hdev->parent)
  2128. delta = 100;
  2129. else
  2130. delta = 8;
  2131. if (delta > hub->mA_per_port)
  2132. dev_warn(&udev->dev, "%dmA is over %umA budget "
  2133. "for port %d!\n",
  2134. delta, hub->mA_per_port, port1);
  2135. remaining -= delta;
  2136. }
  2137. if (remaining < 0) {
  2138. dev_warn(hub->intfdev, "%dmA over power budget!\n",
  2139. - remaining);
  2140. remaining = 0;
  2141. }
  2142. return remaining;
  2143. }
  2144. /* Handle physical or logical connection change events.
  2145. * This routine is called when:
  2146. * a port connection-change occurs;
  2147. * a port enable-change occurs (often caused by EMI);
  2148. * usb_reset_device() encounters changed descriptors (as from
  2149. * a firmware download)
  2150. * caller already locked the hub
  2151. */
  2152. static void hub_port_connect_change(struct usb_hub *hub, int port1,
  2153. u16 portstatus, u16 portchange)
  2154. {
  2155. struct usb_device *hdev = hub->hdev;
  2156. struct device *hub_dev = hub->intfdev;
  2157. u16 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
  2158. int status, i;
  2159. dev_dbg (hub_dev,
  2160. "port %d, status %04x, change %04x, %s\n",
  2161. port1, portstatus, portchange, portspeed (portstatus));
  2162. if (hub->has_indicators) {
  2163. set_port_led(hub, port1, HUB_LED_AUTO);
  2164. hub->indicator[port1-1] = INDICATOR_AUTO;
  2165. }
  2166. /* Disconnect any existing devices under this port */
  2167. if (hdev->children[port1-1])
  2168. usb_disconnect(&hdev->children[port1-1]);
  2169. clear_bit(port1, hub->change_bits);
  2170. #ifdef CONFIG_USB_OTG
  2171. /* during HNP, don't repeat the debounce */
  2172. if (hdev->bus->is_b_host)
  2173. portchange &= ~USB_PORT_STAT_C_CONNECTION;
  2174. #endif
  2175. if (portchange & USB_PORT_STAT_C_CONNECTION) {
  2176. status = hub_port_debounce(hub, port1);
  2177. if (status < 0) {
  2178. dev_err (hub_dev,
  2179. "connect-debounce failed, port %d disabled\n",
  2180. port1);
  2181. goto done;
  2182. }
  2183. portstatus = status;
  2184. }
  2185. /* Return now if nothing is connected */
  2186. if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
  2187. /* maybe switch power back on (e.g. root hub was reset) */
  2188. if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2
  2189. && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
  2190. set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
  2191. if (portstatus & USB_PORT_STAT_ENABLE)
  2192. goto done;
  2193. return;
  2194. }
  2195. #ifdef CONFIG_USB_SUSPEND
  2196. /* If something is connected, but the port is suspended, wake it up. */
  2197. if (portstatus & USB_PORT_STAT_SUSPEND) {
  2198. status = hub_port_resume(hub, port1, NULL);
  2199. if (status < 0) {
  2200. dev_dbg(hub_dev,
  2201. "can't clear suspend on port %d; %d\n",
  2202. port1, status);
  2203. goto done;
  2204. }
  2205. }
  2206. #endif
  2207. for (i = 0; i < SET_CONFIG_TRIES; i++) {
  2208. struct usb_device *udev;
  2209. /* reallocate for each attempt, since references
  2210. * to the previous one can escape in various ways
  2211. */
  2212. udev = usb_alloc_dev(hdev, hdev->bus, port1);
  2213. if (!udev) {
  2214. dev_err (hub_dev,
  2215. "couldn't allocate port %d usb_device\n",
  2216. port1);
  2217. goto done;
  2218. }
  2219. usb_set_device_state(udev, USB_STATE_POWERED);
  2220. udev->speed = USB_SPEED_UNKNOWN;
  2221. udev->bus_mA = hub->mA_per_port;
  2222. /* set the address */
  2223. choose_address(udev);
  2224. if (udev->devnum <= 0) {
  2225. status = -ENOTCONN; /* Don't retry */
  2226. goto loop;
  2227. }
  2228. /* reset and get descriptor */
  2229. status = hub_port_init(hub, udev, port1, i);
  2230. if (status < 0)
  2231. goto loop;
  2232. /* consecutive bus-powered hubs aren't reliable; they can
  2233. * violate the voltage drop budget. if the new child has
  2234. * a "powered" LED, users should notice we didn't enable it
  2235. * (without reading syslog), even without per-port LEDs
  2236. * on the parent.
  2237. */
  2238. if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
  2239. && udev->bus_mA <= 100) {
  2240. u16 devstat;
  2241. status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
  2242. &devstat);
  2243. if (status < 2) {
  2244. dev_dbg(&udev->dev, "get status %d ?\n", status);
  2245. goto loop_disable;
  2246. }
  2247. le16_to_cpus(&devstat);
  2248. if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
  2249. dev_err(&udev->dev,
  2250. "can't connect bus-powered hub "
  2251. "to this port\n");
  2252. if (hub->has_indicators) {
  2253. hub->indicator[port1-1] =
  2254. INDICATOR_AMBER_BLINK;
  2255. schedule_work (&hub->leds);
  2256. }
  2257. status = -ENOTCONN; /* Don't retry */
  2258. goto loop_disable;
  2259. }
  2260. }
  2261. /* check for devices running slower than they could */
  2262. if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
  2263. && udev->speed == USB_SPEED_FULL
  2264. && highspeed_hubs != 0)
  2265. check_highspeed (hub, udev, port1);
  2266. /* Store the parent's children[] pointer. At this point
  2267. * udev becomes globally accessible, although presumably
  2268. * no one will look at it until hdev is unlocked.
  2269. */
  2270. status = 0;
  2271. /* We mustn't add new devices if the parent hub has
  2272. * been disconnected; we would race with the
  2273. * recursively_mark_NOTATTACHED() routine.
  2274. */
  2275. spin_lock_irq(&device_state_lock);
  2276. if (hdev->state == USB_STATE_NOTATTACHED)
  2277. status = -ENOTCONN;
  2278. else
  2279. hdev->children[port1-1] = udev;
  2280. spin_unlock_irq(&device_state_lock);
  2281. /* Run it through the hoops (find a driver, etc) */
  2282. if (!status) {
  2283. status = usb_new_device(udev);
  2284. if (status) {
  2285. spin_lock_irq(&device_state_lock);
  2286. hdev->children[port1-1] = NULL;
  2287. spin_unlock_irq(&device_state_lock);
  2288. }
  2289. }
  2290. if (status)
  2291. goto loop_disable;
  2292. status = hub_power_remaining(hub);
  2293. if (status)
  2294. dev_dbg(hub_dev, "%dmA power budget left\n", status);
  2295. return;
  2296. loop_disable:
  2297. hub_port_disable(hub, port1, 1);
  2298. loop:
  2299. ep0_reinit(udev);
  2300. release_address(udev);
  2301. usb_put_dev(udev);
  2302. if (status == -ENOTCONN)
  2303. break;
  2304. }
  2305. done:
  2306. hub_port_disable(hub, port1, 1);
  2307. }
  2308. static void hub_events(void)
  2309. {
  2310. struct list_head *tmp;
  2311. struct usb_device *hdev;
  2312. struct usb_interface *intf;
  2313. struct usb_hub *hub;
  2314. struct device *hub_dev;
  2315. u16 hubstatus;
  2316. u16 hubchange;
  2317. u16 portstatus;
  2318. u16 portchange;
  2319. int i, ret;
  2320. int connect_change;
  2321. /*
  2322. * We restart the list every time to avoid a deadlock with
  2323. * deleting hubs downstream from this one. This should be
  2324. * safe since we delete the hub from the event list.
  2325. * Not the most efficient, but avoids deadlocks.
  2326. */
  2327. while (1) {
  2328. /* Grab the first entry at the beginning of the list */
  2329. spin_lock_irq(&hub_event_lock);
  2330. if (list_empty(&hub_event_list)) {
  2331. spin_unlock_irq(&hub_event_lock);
  2332. break;
  2333. }
  2334. tmp = hub_event_list.next;
  2335. list_del_init(tmp);
  2336. hub = list_entry(tmp, struct usb_hub, event_list);
  2337. hdev = hub->hdev;
  2338. intf = to_usb_interface(hub->intfdev);
  2339. hub_dev = &intf->dev;
  2340. i = hub->resume_root_hub;
  2341. dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x%s\n",
  2342. hdev->state, hub->descriptor
  2343. ? hub->descriptor->bNbrPorts
  2344. : 0,
  2345. /* NOTE: expects max 15 ports... */
  2346. (u16) hub->change_bits[0],
  2347. (u16) hub->event_bits[0],
  2348. i ? ", resume root" : "");
  2349. usb_get_intf(intf);
  2350. spin_unlock_irq(&hub_event_lock);
  2351. /* Is this is a root hub wanting to reactivate the downstream
  2352. * ports? If so, be sure the interface resumes even if its
  2353. * stub "device" node was never suspended.
  2354. */
  2355. if (i) {
  2356. dpm_runtime_resume(&hdev->dev);
  2357. dpm_runtime_resume(&intf->dev);
  2358. usb_put_intf(intf);
  2359. continue;
  2360. }
  2361. /* Lock the device, then check to see if we were
  2362. * disconnected while waiting for the lock to succeed. */
  2363. if (locktree(hdev) < 0) {
  2364. usb_put_intf(intf);
  2365. continue;
  2366. }
  2367. if (hub != usb_get_intfdata(intf))
  2368. goto loop;
  2369. /* If the hub has died, clean up after it */
  2370. if (hdev->state == USB_STATE_NOTATTACHED) {
  2371. hub_pre_reset(hub, 0);
  2372. goto loop;
  2373. }
  2374. /* If this is an inactive or suspended hub, do nothing */
  2375. if (hub->quiescing)
  2376. goto loop;
  2377. if (hub->error) {
  2378. dev_dbg (hub_dev, "resetting for error %d\n",
  2379. hub->error);
  2380. ret = usb_reset_device(hdev);
  2381. if (ret) {
  2382. dev_dbg (hub_dev,
  2383. "error resetting hub: %d\n", ret);
  2384. goto loop;
  2385. }
  2386. hub->nerrors = 0;
  2387. hub->error = 0;
  2388. }
  2389. /* deal with port status changes */
  2390. for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
  2391. if (test_bit(i, hub->busy_bits))
  2392. continue;
  2393. connect_change = test_bit(i, hub->change_bits);
  2394. if (!test_and_clear_bit(i, hub->event_bits) &&
  2395. !connect_change && !hub->activating)
  2396. continue;
  2397. ret = hub_port_status(hub, i,
  2398. &portstatus, &portchange);
  2399. if (ret < 0)
  2400. continue;
  2401. if (hub->activating && !hdev->children[i-1] &&
  2402. (portstatus &
  2403. USB_PORT_STAT_CONNECTION))
  2404. connect_change = 1;
  2405. if (portchange & USB_PORT_STAT_C_CONNECTION) {
  2406. clear_port_feature(hdev, i,
  2407. USB_PORT_FEAT_C_CONNECTION);
  2408. connect_change = 1;
  2409. }
  2410. if (portchange & USB_PORT_STAT_C_ENABLE) {
  2411. if (!connect_change)
  2412. dev_dbg (hub_dev,
  2413. "port %d enable change, "
  2414. "status %08x\n",
  2415. i, portstatus);
  2416. clear_port_feature(hdev, i,
  2417. USB_PORT_FEAT_C_ENABLE);
  2418. /*
  2419. * EM interference sometimes causes badly
  2420. * shielded USB devices to be shutdown by
  2421. * the hub, this hack enables them again.
  2422. * Works at least with mouse driver.
  2423. */
  2424. if (!(portstatus & USB_PORT_STAT_ENABLE)
  2425. && !connect_change
  2426. && hdev->children[i-1]) {
  2427. dev_err (hub_dev,
  2428. "port %i "
  2429. "disabled by hub (EMI?), "
  2430. "re-enabling...\n",
  2431. i);
  2432. connect_change = 1;
  2433. }
  2434. }
  2435. if (portchange & USB_PORT_STAT_C_SUSPEND) {
  2436. clear_port_feature(hdev, i,
  2437. USB_PORT_FEAT_C_SUSPEND);
  2438. if (hdev->children[i-1]) {
  2439. ret = remote_wakeup(hdev->
  2440. children[i-1]);
  2441. if (ret < 0)
  2442. connect_change = 1;
  2443. } else {
  2444. ret = -ENODEV;
  2445. hub_port_disable(hub, i, 1);
  2446. }
  2447. dev_dbg (hub_dev,
  2448. "resume on port %d, status %d\n",
  2449. i, ret);
  2450. }
  2451. if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
  2452. dev_err (hub_dev,
  2453. "over-current change on port %d\n",
  2454. i);
  2455. clear_port_feature(hdev, i,
  2456. USB_PORT_FEAT_C_OVER_CURRENT);
  2457. hub_power_on(hub);
  2458. }
  2459. if (portchange & USB_PORT_STAT_C_RESET) {
  2460. dev_dbg (hub_dev,
  2461. "reset change on port %d\n",
  2462. i);
  2463. clear_port_feature(hdev, i,
  2464. USB_PORT_FEAT_C_RESET);
  2465. }
  2466. if (connect_change)
  2467. hub_port_connect_change(hub, i,
  2468. portstatus, portchange);
  2469. } /* end for i */
  2470. /* deal with hub status changes */
  2471. if (test_and_clear_bit(0, hub->event_bits) == 0)
  2472. ; /* do nothing */
  2473. else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
  2474. dev_err (hub_dev, "get_hub_status failed\n");
  2475. else {
  2476. if (hubchange & HUB_CHANGE_LOCAL_POWER) {
  2477. dev_dbg (hub_dev, "power change\n");
  2478. clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
  2479. if (hubstatus & HUB_STATUS_LOCAL_POWER)
  2480. /* FIXME: Is this always true? */
  2481. hub->limited_power = 0;
  2482. else
  2483. hub->limited_power = 1;
  2484. }
  2485. if (hubchange & HUB_CHANGE_OVERCURRENT) {
  2486. dev_dbg (hub_dev, "overcurrent change\n");
  2487. msleep(500); /* Cool down */
  2488. clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
  2489. hub_power_on(hub);
  2490. }
  2491. }
  2492. hub->activating = 0;
  2493. /* If this is a root hub, tell the HCD it's okay to
  2494. * re-enable port-change interrupts now. */
  2495. if (!hdev->parent)
  2496. usb_enable_root_hub_irq(hdev->bus);
  2497. loop:
  2498. usb_unlock_device(hdev);
  2499. usb_put_intf(intf);
  2500. } /* end while (1) */
  2501. }
  2502. static int hub_thread(void *__unused)
  2503. {
  2504. do {
  2505. hub_events();
  2506. wait_event_interruptible(khubd_wait,
  2507. !list_empty(&hub_event_list) ||
  2508. kthread_should_stop());
  2509. try_to_freeze();
  2510. } while (!kthread_should_stop() || !list_empty(&hub_event_list));
  2511. pr_debug("%s: khubd exiting\n", usbcore_name);
  2512. return 0;
  2513. }
  2514. static struct usb_device_id hub_id_table [] = {
  2515. { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
  2516. .bDeviceClass = USB_CLASS_HUB},
  2517. { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
  2518. .bInterfaceClass = USB_CLASS_HUB},
  2519. { } /* Terminating entry */
  2520. };
  2521. MODULE_DEVICE_TABLE (usb, hub_id_table);
  2522. static struct usb_driver hub_driver = {
  2523. .name = "hub",
  2524. .probe = hub_probe,
  2525. .disconnect = hub_disconnect,
  2526. .suspend = hub_suspend,
  2527. .resume = hub_resume,
  2528. .ioctl = hub_ioctl,
  2529. .id_table = hub_id_table,
  2530. };
  2531. int usb_hub_init(void)
  2532. {
  2533. if (usb_register(&hub_driver) < 0) {
  2534. printk(KERN_ERR "%s: can't register hub driver\n",
  2535. usbcore_name);
  2536. return -1;
  2537. }
  2538. khubd_task = kthread_run(hub_thread, NULL, "khubd");
  2539. if (!IS_ERR(khubd_task))
  2540. return 0;
  2541. /* Fall through if kernel_thread failed */
  2542. usb_deregister(&hub_driver);
  2543. printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
  2544. return -1;
  2545. }
  2546. void usb_hub_cleanup(void)
  2547. {
  2548. kthread_stop(khubd_task);
  2549. /*
  2550. * Hub resources are freed for us by usb_deregister. It calls
  2551. * usb_driver_purge on every device which in turn calls that
  2552. * devices disconnect function if it is using this driver.
  2553. * The hub_disconnect function takes care of releasing the
  2554. * individual hub resources. -greg
  2555. */
  2556. usb_deregister(&hub_driver);
  2557. } /* usb_hub_cleanup() */
  2558. static int config_descriptors_changed(struct usb_device *udev)
  2559. {
  2560. unsigned index;
  2561. unsigned len = 0;
  2562. struct usb_config_descriptor *buf;
  2563. for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
  2564. if (len < le16_to_cpu(udev->config[index].desc.wTotalLength))
  2565. len = le16_to_cpu(udev->config[index].desc.wTotalLength);
  2566. }
  2567. buf = kmalloc (len, SLAB_KERNEL);
  2568. if (buf == NULL) {
  2569. dev_err(&udev->dev, "no mem to re-read configs after reset\n");
  2570. /* assume the worst */
  2571. return 1;
  2572. }
  2573. for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
  2574. int length;
  2575. int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
  2576. length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
  2577. old_length);
  2578. if (length < old_length) {
  2579. dev_dbg(&udev->dev, "config index %d, error %d\n",
  2580. index, length);
  2581. break;
  2582. }
  2583. if (memcmp (buf, udev->rawdescriptors[index], old_length)
  2584. != 0) {
  2585. dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
  2586. index, buf->bConfigurationValue);
  2587. break;
  2588. }
  2589. }
  2590. kfree(buf);
  2591. return index != udev->descriptor.bNumConfigurations;
  2592. }
  2593. /**
  2594. * usb_reset_device - perform a USB port reset to reinitialize a device
  2595. * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
  2596. *
  2597. * WARNING - don't reset any device unless drivers for all of its
  2598. * interfaces are expecting that reset! Maybe some driver->reset()
  2599. * method should eventually help ensure sufficient cooperation.
  2600. *
  2601. * Do a port reset, reassign the device's address, and establish its
  2602. * former operating configuration. If the reset fails, or the device's
  2603. * descriptors change from their values before the reset, or the original
  2604. * configuration and altsettings cannot be restored, a flag will be set
  2605. * telling khubd to pretend the device has been disconnected and then
  2606. * re-connected. All drivers will be unbound, and the device will be
  2607. * re-enumerated and probed all over again.
  2608. *
  2609. * Returns 0 if the reset succeeded, -ENODEV if the device has been
  2610. * flagged for logical disconnection, or some other negative error code
  2611. * if the reset wasn't even attempted.
  2612. *
  2613. * The caller must own the device lock. For example, it's safe to use
  2614. * this from a driver probe() routine after downloading new firmware.
  2615. * For calls that might not occur during probe(), drivers should lock
  2616. * the device using usb_lock_device_for_reset().
  2617. */
  2618. int usb_reset_device(struct usb_device *udev)
  2619. {
  2620. struct usb_device *parent_hdev = udev->parent;
  2621. struct usb_hub *parent_hub;
  2622. struct usb_device_descriptor descriptor = udev->descriptor;
  2623. struct usb_hub *hub = NULL;
  2624. int i, ret = 0;
  2625. int port1 = udev->portnum;
  2626. if (udev->state == USB_STATE_NOTATTACHED ||
  2627. udev->state == USB_STATE_SUSPENDED) {
  2628. dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
  2629. udev->state);
  2630. return -EINVAL;
  2631. }
  2632. if (!parent_hdev) {
  2633. /* this requires hcd-specific logic; see OHCI hc_restart() */
  2634. dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
  2635. return -EISDIR;
  2636. }
  2637. parent_hub = hdev_to_hub(parent_hdev);
  2638. /* If we're resetting an active hub, take some special actions */
  2639. if (udev->actconfig && udev->actconfig->desc.bNumInterfaces > 0 &&
  2640. udev->actconfig->interface[0]->dev.driver ==
  2641. &hub_driver.driver &&
  2642. (hub = hdev_to_hub(udev)) != NULL) {
  2643. hub_pre_reset(hub, 0);
  2644. }
  2645. set_bit(port1, parent_hub->busy_bits);
  2646. for (i = 0; i < SET_CONFIG_TRIES; ++i) {
  2647. /* ep0 maxpacket size may change; let the HCD know about it.
  2648. * Other endpoints will be handled by re-enumeration. */
  2649. ep0_reinit(udev);
  2650. ret = hub_port_init(parent_hub, udev, port1, i);
  2651. if (ret >= 0)
  2652. break;
  2653. }
  2654. clear_bit(port1, parent_hub->busy_bits);
  2655. if (ret < 0)
  2656. goto re_enumerate;
  2657. /* Device might have changed firmware (DFU or similar) */
  2658. if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
  2659. || config_descriptors_changed (udev)) {
  2660. dev_info(&udev->dev, "device firmware changed\n");
  2661. udev->descriptor = descriptor; /* for disconnect() calls */
  2662. goto re_enumerate;
  2663. }
  2664. if (!udev->actconfig)
  2665. goto done;
  2666. ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
  2667. USB_REQ_SET_CONFIGURATION, 0,
  2668. udev->actconfig->desc.bConfigurationValue, 0,
  2669. NULL, 0, USB_CTRL_SET_TIMEOUT);
  2670. if (ret < 0) {
  2671. dev_err(&udev->dev,
  2672. "can't restore configuration #%d (error=%d)\n",
  2673. udev->actconfig->desc.bConfigurationValue, ret);
  2674. goto re_enumerate;
  2675. }
  2676. usb_set_device_state(udev, USB_STATE_CONFIGURED);
  2677. for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
  2678. struct usb_interface *intf = udev->actconfig->interface[i];
  2679. struct usb_interface_descriptor *desc;
  2680. /* set_interface resets host side toggle even
  2681. * for altsetting zero. the interface may have no driver.
  2682. */
  2683. desc = &intf->cur_altsetting->desc;
  2684. ret = usb_set_interface(udev, desc->bInterfaceNumber,
  2685. desc->bAlternateSetting);
  2686. if (ret < 0) {
  2687. dev_err(&udev->dev, "failed to restore interface %d "
  2688. "altsetting %d (error=%d)\n",
  2689. desc->bInterfaceNumber,
  2690. desc->bAlternateSetting,
  2691. ret);
  2692. goto re_enumerate;
  2693. }
  2694. }
  2695. done:
  2696. if (hub)
  2697. hub_post_reset(hub);
  2698. return 0;
  2699. re_enumerate:
  2700. hub_port_logical_disconnect(parent_hub, port1);
  2701. return -ENODEV;
  2702. }