746f26f222ab2567b8767eb8e007d416f0f5a45b
[linux-2.6.git] / drivers / usb / core / hub.c
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
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/ioctl.h>
20 #include <linux/usb.h>
21 #include <linux/usbdevice_fs.h>
22 #include <linux/kthread.h>
23 #include <linux/mutex.h>
24 #include <linux/freezer.h>
25
26 #include <asm/uaccess.h>
27 #include <asm/byteorder.h>
28
29 #include "usb.h"
30 #include "hcd.h"
31 #include "hub.h"
32
33 /* if we are in debug mode, always announce new devices */
34 #ifdef DEBUG
35 #ifndef CONFIG_USB_ANNOUNCE_NEW_DEVICES
36 #define CONFIG_USB_ANNOUNCE_NEW_DEVICES
37 #endif
38 #endif
39
40 struct usb_hub {
41         struct device           *intfdev;       /* the "interface" device */
42         struct usb_device       *hdev;
43         struct kref             kref;
44         struct urb              *urb;           /* for interrupt polling pipe */
45
46         /* buffer for urb ... with extra space in case of babble */
47         char                    (*buffer)[8];
48         union {
49                 struct usb_hub_status   hub;
50                 struct usb_port_status  port;
51         }                       *status;        /* buffer for status reports */
52         struct mutex            status_mutex;   /* for the status buffer */
53
54         int                     error;          /* last reported error */
55         int                     nerrors;        /* track consecutive errors */
56
57         struct list_head        event_list;     /* hubs w/data or errs ready */
58         unsigned long           event_bits[1];  /* status change bitmask */
59         unsigned long           change_bits[1]; /* ports with logical connect
60                                                         status change */
61         unsigned long           busy_bits[1];   /* ports being reset or
62                                                         resumed */
63         unsigned long           removed_bits[1]; /* ports with a "removed"
64                                                         device present */
65 #if USB_MAXCHILDREN > 31 /* 8*sizeof(unsigned long) - 1 */
66 #error event_bits[] is too short!
67 #endif
68
69         struct usb_hub_descriptor *descriptor;  /* class descriptor */
70         struct usb_tt           tt;             /* Transaction Translator */
71
72         unsigned                mA_per_port;    /* current for each child */
73
74         unsigned                init_done:1;
75         unsigned                limited_power:1;
76         unsigned                quiescing:1;
77         unsigned                disconnected:1;
78
79         unsigned                has_indicators:1;
80         u8                      indicator[USB_MAXCHILDREN];
81         struct delayed_work     leds;
82         struct delayed_work     init_work;
83         void                    **port_owners;
84 };
85
86
87 /* Protect struct usb_device->state and ->children members
88  * Note: Both are also protected by ->dev.sem, except that ->state can
89  * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
90 static DEFINE_SPINLOCK(device_state_lock);
91
92 /* khubd's worklist and its lock */
93 static DEFINE_SPINLOCK(hub_event_lock);
94 static LIST_HEAD(hub_event_list);       /* List of hubs needing servicing */
95
96 /* Wakes up khubd */
97 static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
98
99 static struct task_struct *khubd_task;
100
101 /* cycle leds on hubs that aren't blinking for attention */
102 static int blinkenlights = 0;
103 module_param (blinkenlights, bool, S_IRUGO);
104 MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
105
106 /*
107  * Device SATA8000 FW1.0 from DATAST0R Technology Corp requires about
108  * 10 seconds to send reply for the initial 64-byte descriptor request.
109  */
110 /* define initial 64-byte descriptor request timeout in milliseconds */
111 static int initial_descriptor_timeout = USB_CTRL_GET_TIMEOUT;
112 module_param(initial_descriptor_timeout, int, S_IRUGO|S_IWUSR);
113 MODULE_PARM_DESC(initial_descriptor_timeout,
114                 "initial 64-byte descriptor request timeout in milliseconds "
115                 "(default 5000 - 5.0 seconds)");
116
117 /*
118  * As of 2.6.10 we introduce a new USB device initialization scheme which
119  * closely resembles the way Windows works.  Hopefully it will be compatible
120  * with a wider range of devices than the old scheme.  However some previously
121  * working devices may start giving rise to "device not accepting address"
122  * errors; if that happens the user can try the old scheme by adjusting the
123  * following module parameters.
124  *
125  * For maximum flexibility there are two boolean parameters to control the
126  * hub driver's behavior.  On the first initialization attempt, if the
127  * "old_scheme_first" parameter is set then the old scheme will be used,
128  * otherwise the new scheme is used.  If that fails and "use_both_schemes"
129  * is set, then the driver will make another attempt, using the other scheme.
130  */
131 static int old_scheme_first = 0;
132 module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
133 MODULE_PARM_DESC(old_scheme_first,
134                  "start with the old device initialization scheme");
135
136 static int use_both_schemes = 1;
137 module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
138 MODULE_PARM_DESC(use_both_schemes,
139                 "try the other device initialization scheme if the "
140                 "first one fails");
141
142 /* Mutual exclusion for EHCI CF initialization.  This interferes with
143  * port reset on some companion controllers.
144  */
145 DECLARE_RWSEM(ehci_cf_port_reset_rwsem);
146 EXPORT_SYMBOL_GPL(ehci_cf_port_reset_rwsem);
147
148 #define HUB_DEBOUNCE_TIMEOUT    1500
149 #define HUB_DEBOUNCE_STEP         25
150 #define HUB_DEBOUNCE_STABLE      100
151
152
153 static int usb_reset_and_verify_device(struct usb_device *udev);
154
155 static inline char *portspeed(int portstatus)
156 {
157         if (portstatus & (1 << USB_PORT_FEAT_HIGHSPEED))
158                 return "480 Mb/s";
159         else if (portstatus & (1 << USB_PORT_FEAT_LOWSPEED))
160                 return "1.5 Mb/s";
161         else if (portstatus & (1 << USB_PORT_FEAT_SUPERSPEED))
162                 return "5.0 Gb/s";
163         else
164                 return "12 Mb/s";
165 }
166
167 /* Note that hdev or one of its children must be locked! */
168 static struct usb_hub *hdev_to_hub(struct usb_device *hdev)
169 {
170         if (!hdev || !hdev->actconfig)
171                 return NULL;
172         return usb_get_intfdata(hdev->actconfig->interface[0]);
173 }
174
175 /* USB 2.0 spec Section 11.24.4.5 */
176 static int get_hub_descriptor(struct usb_device *hdev, void *data, int size)
177 {
178         int i, ret;
179
180         for (i = 0; i < 3; i++) {
181                 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
182                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
183                         USB_DT_HUB << 8, 0, data, size,
184                         USB_CTRL_GET_TIMEOUT);
185                 if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
186                         return ret;
187         }
188         return -EINVAL;
189 }
190
191 /*
192  * USB 2.0 spec Section 11.24.2.1
193  */
194 static int clear_hub_feature(struct usb_device *hdev, int feature)
195 {
196         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
197                 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
198 }
199
200 /*
201  * USB 2.0 spec Section 11.24.2.2
202  */
203 static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
204 {
205         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
206                 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
207                 NULL, 0, 1000);
208 }
209
210 /*
211  * USB 2.0 spec Section 11.24.2.13
212  */
213 static int set_port_feature(struct usb_device *hdev, int port1, int feature)
214 {
215         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
216                 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
217                 NULL, 0, 1000);
218 }
219
220 /*
221  * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
222  * for info about using port indicators
223  */
224 static void set_port_led(
225         struct usb_hub *hub,
226         int port1,
227         int selector
228 )
229 {
230         int status = set_port_feature(hub->hdev, (selector << 8) | port1,
231                         USB_PORT_FEAT_INDICATOR);
232         if (status < 0)
233                 dev_dbg (hub->intfdev,
234                         "port %d indicator %s status %d\n",
235                         port1,
236                         ({ char *s; switch (selector) {
237                         case HUB_LED_AMBER: s = "amber"; break;
238                         case HUB_LED_GREEN: s = "green"; break;
239                         case HUB_LED_OFF: s = "off"; break;
240                         case HUB_LED_AUTO: s = "auto"; break;
241                         default: s = "??"; break;
242                         }; s; }),
243                         status);
244 }
245
246 #define LED_CYCLE_PERIOD        ((2*HZ)/3)
247
248 static void led_work (struct work_struct *work)
249 {
250         struct usb_hub          *hub =
251                 container_of(work, struct usb_hub, leds.work);
252         struct usb_device       *hdev = hub->hdev;
253         unsigned                i;
254         unsigned                changed = 0;
255         int                     cursor = -1;
256
257         if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
258                 return;
259
260         for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
261                 unsigned        selector, mode;
262
263                 /* 30%-50% duty cycle */
264
265                 switch (hub->indicator[i]) {
266                 /* cycle marker */
267                 case INDICATOR_CYCLE:
268                         cursor = i;
269                         selector = HUB_LED_AUTO;
270                         mode = INDICATOR_AUTO;
271                         break;
272                 /* blinking green = sw attention */
273                 case INDICATOR_GREEN_BLINK:
274                         selector = HUB_LED_GREEN;
275                         mode = INDICATOR_GREEN_BLINK_OFF;
276                         break;
277                 case INDICATOR_GREEN_BLINK_OFF:
278                         selector = HUB_LED_OFF;
279                         mode = INDICATOR_GREEN_BLINK;
280                         break;
281                 /* blinking amber = hw attention */
282                 case INDICATOR_AMBER_BLINK:
283                         selector = HUB_LED_AMBER;
284                         mode = INDICATOR_AMBER_BLINK_OFF;
285                         break;
286                 case INDICATOR_AMBER_BLINK_OFF:
287                         selector = HUB_LED_OFF;
288                         mode = INDICATOR_AMBER_BLINK;
289                         break;
290                 /* blink green/amber = reserved */
291                 case INDICATOR_ALT_BLINK:
292                         selector = HUB_LED_GREEN;
293                         mode = INDICATOR_ALT_BLINK_OFF;
294                         break;
295                 case INDICATOR_ALT_BLINK_OFF:
296                         selector = HUB_LED_AMBER;
297                         mode = INDICATOR_ALT_BLINK;
298                         break;
299                 default:
300                         continue;
301                 }
302                 if (selector != HUB_LED_AUTO)
303                         changed = 1;
304                 set_port_led(hub, i + 1, selector);
305                 hub->indicator[i] = mode;
306         }
307         if (!changed && blinkenlights) {
308                 cursor++;
309                 cursor %= hub->descriptor->bNbrPorts;
310                 set_port_led(hub, cursor + 1, HUB_LED_GREEN);
311                 hub->indicator[cursor] = INDICATOR_CYCLE;
312                 changed++;
313         }
314         if (changed)
315                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
316 }
317
318 /* use a short timeout for hub/port status fetches */
319 #define USB_STS_TIMEOUT         1000
320 #define USB_STS_RETRIES         5
321
322 /*
323  * USB 2.0 spec Section 11.24.2.6
324  */
325 static int get_hub_status(struct usb_device *hdev,
326                 struct usb_hub_status *data)
327 {
328         int i, status = -ETIMEDOUT;
329
330         for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
331                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
332                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
333                         data, sizeof(*data), USB_STS_TIMEOUT);
334         }
335         return status;
336 }
337
338 /*
339  * USB 2.0 spec Section 11.24.2.7
340  */
341 static int get_port_status(struct usb_device *hdev, int port1,
342                 struct usb_port_status *data)
343 {
344         int i, status = -ETIMEDOUT;
345
346         for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
347                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
348                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
349                         data, sizeof(*data), USB_STS_TIMEOUT);
350         }
351         return status;
352 }
353
354 static int hub_port_status(struct usb_hub *hub, int port1,
355                 u16 *status, u16 *change)
356 {
357         int ret;
358
359         mutex_lock(&hub->status_mutex);
360         ret = get_port_status(hub->hdev, port1, &hub->status->port);
361         if (ret < 4) {
362                 dev_err(hub->intfdev,
363                         "%s failed (err = %d)\n", __func__, ret);
364                 if (ret >= 0)
365                         ret = -EIO;
366         } else {
367                 *status = le16_to_cpu(hub->status->port.wPortStatus);
368                 *change = le16_to_cpu(hub->status->port.wPortChange);
369                 ret = 0;
370         }
371         mutex_unlock(&hub->status_mutex);
372         return ret;
373 }
374
375 static void kick_khubd(struct usb_hub *hub)
376 {
377         unsigned long   flags;
378
379         spin_lock_irqsave(&hub_event_lock, flags);
380         if (!hub->disconnected && list_empty(&hub->event_list)) {
381                 list_add_tail(&hub->event_list, &hub_event_list);
382
383                 /* Suppress autosuspend until khubd runs */
384                 usb_autopm_get_interface_no_resume(
385                                 to_usb_interface(hub->intfdev));
386                 wake_up(&khubd_wait);
387         }
388         spin_unlock_irqrestore(&hub_event_lock, flags);
389 }
390
391 void usb_kick_khubd(struct usb_device *hdev)
392 {
393         struct usb_hub *hub = hdev_to_hub(hdev);
394
395         if (hub)
396                 kick_khubd(hub);
397 }
398
399
400 /* completion function, fires on port status changes and various faults */
401 static void hub_irq(struct urb *urb)
402 {
403         struct usb_hub *hub = urb->context;
404         int status = urb->status;
405         unsigned i;
406         unsigned long bits;
407
408         switch (status) {
409         case -ENOENT:           /* synchronous unlink */
410         case -ECONNRESET:       /* async unlink */
411         case -ESHUTDOWN:        /* hardware going away */
412                 return;
413
414         default:                /* presumably an error */
415                 /* Cause a hub reset after 10 consecutive errors */
416                 dev_dbg (hub->intfdev, "transfer --> %d\n", status);
417                 if ((++hub->nerrors < 10) || hub->error)
418                         goto resubmit;
419                 hub->error = status;
420                 /* FALL THROUGH */
421
422         /* let khubd handle things */
423         case 0:                 /* we got data:  port status changed */
424                 bits = 0;
425                 for (i = 0; i < urb->actual_length; ++i)
426                         bits |= ((unsigned long) ((*hub->buffer)[i]))
427                                         << (i*8);
428                 hub->event_bits[0] = bits;
429                 break;
430         }
431
432         hub->nerrors = 0;
433
434         /* Something happened, let khubd figure it out */
435         kick_khubd(hub);
436
437 resubmit:
438         if (hub->quiescing)
439                 return;
440
441         if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
442                         && status != -ENODEV && status != -EPERM)
443                 dev_err (hub->intfdev, "resubmit --> %d\n", status);
444 }
445
446 /* USB 2.0 spec Section 11.24.2.3 */
447 static inline int
448 hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
449 {
450         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
451                                HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
452                                tt, NULL, 0, 1000);
453 }
454
455 /*
456  * enumeration blocks khubd for a long time. we use keventd instead, since
457  * long blocking there is the exception, not the rule.  accordingly, HCDs
458  * talking to TTs must queue control transfers (not just bulk and iso), so
459  * both can talk to the same hub concurrently.
460  */
461 static void hub_tt_work(struct work_struct *work)
462 {
463         struct usb_hub          *hub =
464                 container_of(work, struct usb_hub, tt.clear_work);
465         unsigned long           flags;
466         int                     limit = 100;
467
468         spin_lock_irqsave (&hub->tt.lock, flags);
469         while (--limit && !list_empty (&hub->tt.clear_list)) {
470                 struct list_head        *next;
471                 struct usb_tt_clear     *clear;
472                 struct usb_device       *hdev = hub->hdev;
473                 const struct hc_driver  *drv;
474                 int                     status;
475
476                 next = hub->tt.clear_list.next;
477                 clear = list_entry (next, struct usb_tt_clear, clear_list);
478                 list_del (&clear->clear_list);
479
480                 /* drop lock so HCD can concurrently report other TT errors */
481                 spin_unlock_irqrestore (&hub->tt.lock, flags);
482                 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
483                 if (status)
484                         dev_err (&hdev->dev,
485                                 "clear tt %d (%04x) error %d\n",
486                                 clear->tt, clear->devinfo, status);
487
488                 /* Tell the HCD, even if the operation failed */
489                 drv = clear->hcd->driver;
490                 if (drv->clear_tt_buffer_complete)
491                         (drv->clear_tt_buffer_complete)(clear->hcd, clear->ep);
492
493                 kfree(clear);
494                 spin_lock_irqsave(&hub->tt.lock, flags);
495         }
496         spin_unlock_irqrestore (&hub->tt.lock, flags);
497 }
498
499 /**
500  * usb_hub_clear_tt_buffer - clear control/bulk TT state in high speed hub
501  * @urb: an URB associated with the failed or incomplete split transaction
502  *
503  * High speed HCDs use this to tell the hub driver that some split control or
504  * bulk transaction failed in a way that requires clearing internal state of
505  * a transaction translator.  This is normally detected (and reported) from
506  * interrupt context.
507  *
508  * It may not be possible for that hub to handle additional full (or low)
509  * speed transactions until that state is fully cleared out.
510  */
511 int usb_hub_clear_tt_buffer(struct urb *urb)
512 {
513         struct usb_device       *udev = urb->dev;
514         int                     pipe = urb->pipe;
515         struct usb_tt           *tt = udev->tt;
516         unsigned long           flags;
517         struct usb_tt_clear     *clear;
518
519         /* we've got to cope with an arbitrary number of pending TT clears,
520          * since each TT has "at least two" buffers that can need it (and
521          * there can be many TTs per hub).  even if they're uncommon.
522          */
523         if ((clear = kmalloc (sizeof *clear, GFP_ATOMIC)) == NULL) {
524                 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
525                 /* FIXME recover somehow ... RESET_TT? */
526                 return -ENOMEM;
527         }
528
529         /* info that CLEAR_TT_BUFFER needs */
530         clear->tt = tt->multi ? udev->ttport : 1;
531         clear->devinfo = usb_pipeendpoint (pipe);
532         clear->devinfo |= udev->devnum << 4;
533         clear->devinfo |= usb_pipecontrol (pipe)
534                         ? (USB_ENDPOINT_XFER_CONTROL << 11)
535                         : (USB_ENDPOINT_XFER_BULK << 11);
536         if (usb_pipein (pipe))
537                 clear->devinfo |= 1 << 15;
538
539         /* info for completion callback */
540         clear->hcd = bus_to_hcd(udev->bus);
541         clear->ep = urb->ep;
542
543         /* tell keventd to clear state for this TT */
544         spin_lock_irqsave (&tt->lock, flags);
545         list_add_tail (&clear->clear_list, &tt->clear_list);
546         schedule_work(&tt->clear_work);
547         spin_unlock_irqrestore (&tt->lock, flags);
548         return 0;
549 }
550 EXPORT_SYMBOL_GPL(usb_hub_clear_tt_buffer);
551
552 /* If do_delay is false, return the number of milliseconds the caller
553  * needs to delay.
554  */
555 static unsigned hub_power_on(struct usb_hub *hub, bool do_delay)
556 {
557         int port1;
558         unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
559         unsigned delay;
560         u16 wHubCharacteristics =
561                         le16_to_cpu(hub->descriptor->wHubCharacteristics);
562
563         /* Enable power on each port.  Some hubs have reserved values
564          * of LPSM (> 2) in their descriptors, even though they are
565          * USB 2.0 hubs.  Some hubs do not implement port-power switching
566          * but only emulate it.  In all cases, the ports won't work
567          * unless we send these messages to the hub.
568          */
569         if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2)
570                 dev_dbg(hub->intfdev, "enabling power on all ports\n");
571         else
572                 dev_dbg(hub->intfdev, "trying to enable port power on "
573                                 "non-switchable hub\n");
574         for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
575                 set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
576
577         /* Wait at least 100 msec for power to become stable */
578         delay = max(pgood_delay, (unsigned) 100);
579         if (do_delay)
580                 msleep(delay);
581         return delay;
582 }
583
584 static int hub_hub_status(struct usb_hub *hub,
585                 u16 *status, u16 *change)
586 {
587         int ret;
588
589         mutex_lock(&hub->status_mutex);
590         ret = get_hub_status(hub->hdev, &hub->status->hub);
591         if (ret < 0)
592                 dev_err (hub->intfdev,
593                         "%s failed (err = %d)\n", __func__, ret);
594         else {
595                 *status = le16_to_cpu(hub->status->hub.wHubStatus);
596                 *change = le16_to_cpu(hub->status->hub.wHubChange); 
597                 ret = 0;
598         }
599         mutex_unlock(&hub->status_mutex);
600         return ret;
601 }
602
603 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
604 {
605         struct usb_device *hdev = hub->hdev;
606         int ret = 0;
607
608         if (hdev->children[port1-1] && set_state)
609                 usb_set_device_state(hdev->children[port1-1],
610                                 USB_STATE_NOTATTACHED);
611         if (!hub->error)
612                 ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
613         if (ret)
614                 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
615                                 port1, ret);
616         return ret;
617 }
618
619 /*
620  * Disable a port and mark a logical connnect-change event, so that some
621  * time later khubd will disconnect() any existing usb_device on the port
622  * and will re-enumerate if there actually is a device attached.
623  */
624 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
625 {
626         dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
627         hub_port_disable(hub, port1, 1);
628
629         /* FIXME let caller ask to power down the port:
630          *  - some devices won't enumerate without a VBUS power cycle
631          *  - SRP saves power that way
632          *  - ... new call, TBD ...
633          * That's easy if this hub can switch power per-port, and
634          * khubd reactivates the port later (timer, SRP, etc).
635          * Powerdown must be optional, because of reset/DFU.
636          */
637
638         set_bit(port1, hub->change_bits);
639         kick_khubd(hub);
640 }
641
642 /**
643  * usb_remove_device - disable a device's port on its parent hub
644  * @udev: device to be disabled and removed
645  * Context: @udev locked, must be able to sleep.
646  *
647  * After @udev's port has been disabled, khubd is notified and it will
648  * see that the device has been disconnected.  When the device is
649  * physically unplugged and something is plugged in, the events will
650  * be received and processed normally.
651  */
652 int usb_remove_device(struct usb_device *udev)
653 {
654         struct usb_hub *hub;
655         struct usb_interface *intf;
656
657         if (!udev->parent)      /* Can't remove a root hub */
658                 return -EINVAL;
659         hub = hdev_to_hub(udev->parent);
660         intf = to_usb_interface(hub->intfdev);
661
662         usb_autopm_get_interface(intf);
663         set_bit(udev->portnum, hub->removed_bits);
664         hub_port_logical_disconnect(hub, udev->portnum);
665         usb_autopm_put_interface(intf);
666         return 0;
667 }
668
669 enum hub_activation_type {
670         HUB_INIT, HUB_INIT2, HUB_INIT3,         /* INITs must come first */
671         HUB_POST_RESET, HUB_RESUME, HUB_RESET_RESUME,
672 };
673
674 static void hub_init_func2(struct work_struct *ws);
675 static void hub_init_func3(struct work_struct *ws);
676
677 static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
678 {
679         struct usb_device *hdev = hub->hdev;
680         int port1;
681         int status;
682         bool need_debounce_delay = false;
683         unsigned delay;
684
685         /* Continue a partial initialization */
686         if (type == HUB_INIT2)
687                 goto init2;
688         if (type == HUB_INIT3)
689                 goto init3;
690
691         /* After a resume, port power should still be on.
692          * For any other type of activation, turn it on.
693          */
694         if (type != HUB_RESUME) {
695
696                 /* Speed up system boot by using a delayed_work for the
697                  * hub's initial power-up delays.  This is pretty awkward
698                  * and the implementation looks like a home-brewed sort of
699                  * setjmp/longjmp, but it saves at least 100 ms for each
700                  * root hub (assuming usbcore is compiled into the kernel
701                  * rather than as a module).  It adds up.
702                  *
703                  * This can't be done for HUB_RESUME or HUB_RESET_RESUME
704                  * because for those activation types the ports have to be
705                  * operational when we return.  In theory this could be done
706                  * for HUB_POST_RESET, but it's easier not to.
707                  */
708                 if (type == HUB_INIT) {
709                         delay = hub_power_on(hub, false);
710                         PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func2);
711                         schedule_delayed_work(&hub->init_work,
712                                         msecs_to_jiffies(delay));
713
714                         /* Suppress autosuspend until init is done */
715                         usb_autopm_get_interface_no_resume(
716                                         to_usb_interface(hub->intfdev));
717                         return;         /* Continues at init2: below */
718                 } else {
719                         hub_power_on(hub, true);
720                 }
721         }
722  init2:
723
724         /* Check each port and set hub->change_bits to let khubd know
725          * which ports need attention.
726          */
727         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
728                 struct usb_device *udev = hdev->children[port1-1];
729                 u16 portstatus, portchange;
730
731                 portstatus = portchange = 0;
732                 status = hub_port_status(hub, port1, &portstatus, &portchange);
733                 if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
734                         dev_dbg(hub->intfdev,
735                                         "port %d: status %04x change %04x\n",
736                                         port1, portstatus, portchange);
737
738                 /* After anything other than HUB_RESUME (i.e., initialization
739                  * or any sort of reset), every port should be disabled.
740                  * Unconnected ports should likewise be disabled (paranoia),
741                  * and so should ports for which we have no usb_device.
742                  */
743                 if ((portstatus & USB_PORT_STAT_ENABLE) && (
744                                 type != HUB_RESUME ||
745                                 !(portstatus & USB_PORT_STAT_CONNECTION) ||
746                                 !udev ||
747                                 udev->state == USB_STATE_NOTATTACHED)) {
748                         clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
749                         portstatus &= ~USB_PORT_STAT_ENABLE;
750                 }
751
752                 /* Clear status-change flags; we'll debounce later */
753                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
754                         need_debounce_delay = true;
755                         clear_port_feature(hub->hdev, port1,
756                                         USB_PORT_FEAT_C_CONNECTION);
757                 }
758                 if (portchange & USB_PORT_STAT_C_ENABLE) {
759                         need_debounce_delay = true;
760                         clear_port_feature(hub->hdev, port1,
761                                         USB_PORT_FEAT_C_ENABLE);
762                 }
763
764                 /* We can forget about a "removed" device when there's a
765                  * physical disconnect or the connect status changes.
766                  */
767                 if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
768                                 (portchange & USB_PORT_STAT_C_CONNECTION))
769                         clear_bit(port1, hub->removed_bits);
770
771                 if (!udev || udev->state == USB_STATE_NOTATTACHED) {
772                         /* Tell khubd to disconnect the device or
773                          * check for a new connection
774                          */
775                         if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
776                                 set_bit(port1, hub->change_bits);
777
778                 } else if (portstatus & USB_PORT_STAT_ENABLE) {
779                         /* The power session apparently survived the resume.
780                          * If there was an overcurrent or suspend change
781                          * (i.e., remote wakeup request), have khubd
782                          * take care of it.
783                          */
784                         if (portchange)
785                                 set_bit(port1, hub->change_bits);
786
787                 } else if (udev->persist_enabled) {
788 #ifdef CONFIG_PM
789                         udev->reset_resume = 1;
790 #endif
791                         set_bit(port1, hub->change_bits);
792
793                 } else {
794                         /* The power session is gone; tell khubd */
795                         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
796                         set_bit(port1, hub->change_bits);
797                 }
798         }
799
800         /* If no port-status-change flags were set, we don't need any
801          * debouncing.  If flags were set we can try to debounce the
802          * ports all at once right now, instead of letting khubd do them
803          * one at a time later on.
804          *
805          * If any port-status changes do occur during this delay, khubd
806          * will see them later and handle them normally.
807          */
808         if (need_debounce_delay) {
809                 delay = HUB_DEBOUNCE_STABLE;
810
811                 /* Don't do a long sleep inside a workqueue routine */
812                 if (type == HUB_INIT2) {
813                         PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func3);
814                         schedule_delayed_work(&hub->init_work,
815                                         msecs_to_jiffies(delay));
816                         return;         /* Continues at init3: below */
817                 } else {
818                         msleep(delay);
819                 }
820         }
821  init3:
822         hub->quiescing = 0;
823         hub->init_done = 1;
824
825         status = usb_submit_urb(hub->urb, GFP_NOIO);
826         if (status < 0)
827                 dev_err(hub->intfdev, "activate --> %d\n", status);
828         if (hub->has_indicators && blinkenlights)
829                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
830
831         /* Scan all ports that need attention */
832         kick_khubd(hub);
833
834         /* Allow autosuspend if it was suppressed */
835         if (type <= HUB_INIT3)
836                 usb_autopm_put_interface_async(to_usb_interface(hub->intfdev));
837 }
838
839 /* Implement the continuations for the delays above */
840 static void hub_init_func2(struct work_struct *ws)
841 {
842         struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
843
844         hub_activate(hub, HUB_INIT2);
845 }
846
847 static void hub_init_func3(struct work_struct *ws)
848 {
849         struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
850
851         hub_activate(hub, HUB_INIT3);
852 }
853
854 enum hub_quiescing_type {
855         HUB_DISCONNECT, HUB_PRE_RESET, HUB_SUSPEND
856 };
857
858 static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type)
859 {
860         struct usb_device *hdev = hub->hdev;
861         int i;
862
863         cancel_delayed_work_sync(&hub->init_work);
864         if (!hub->init_done) {
865                 hub->init_done = 1;
866                 usb_autopm_put_interface_no_suspend(
867                                 to_usb_interface(hub->intfdev));
868         }
869
870         /* khubd and related activity won't re-trigger */
871         hub->quiescing = 1;
872
873         if (type != HUB_SUSPEND) {
874                 /* Disconnect all the children */
875                 for (i = 0; i < hdev->maxchild; ++i) {
876                         if (hdev->children[i])
877                                 usb_disconnect(&hdev->children[i]);
878                 }
879         }
880
881         /* Stop khubd and related activity */
882         usb_kill_urb(hub->urb);
883         if (hub->has_indicators)
884                 cancel_delayed_work_sync(&hub->leds);
885         if (hub->tt.hub)
886                 cancel_work_sync(&hub->tt.clear_work);
887 }
888
889 /* caller has locked the hub device */
890 static int hub_pre_reset(struct usb_interface *intf)
891 {
892         struct usb_hub *hub = usb_get_intfdata(intf);
893
894         hub_quiesce(hub, HUB_PRE_RESET);
895         return 0;
896 }
897
898 /* caller has locked the hub device */
899 static int hub_post_reset(struct usb_interface *intf)
900 {
901         struct usb_hub *hub = usb_get_intfdata(intf);
902
903         hub_activate(hub, HUB_POST_RESET);
904         return 0;
905 }
906
907 static int hub_configure(struct usb_hub *hub,
908         struct usb_endpoint_descriptor *endpoint)
909 {
910         struct usb_hcd *hcd;
911         struct usb_device *hdev = hub->hdev;
912         struct device *hub_dev = hub->intfdev;
913         u16 hubstatus, hubchange;
914         u16 wHubCharacteristics;
915         unsigned int pipe;
916         int maxp, ret;
917         char *message = "out of memory";
918
919         hub->buffer = kmalloc(sizeof(*hub->buffer), GFP_KERNEL);
920         if (!hub->buffer) {
921                 ret = -ENOMEM;
922                 goto fail;
923         }
924
925         hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
926         if (!hub->status) {
927                 ret = -ENOMEM;
928                 goto fail;
929         }
930         mutex_init(&hub->status_mutex);
931
932         hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
933         if (!hub->descriptor) {
934                 ret = -ENOMEM;
935                 goto fail;
936         }
937
938         /* Request the entire hub descriptor.
939          * hub->descriptor can handle USB_MAXCHILDREN ports,
940          * but the hub can/will return fewer bytes here.
941          */
942         ret = get_hub_descriptor(hdev, hub->descriptor,
943                         sizeof(*hub->descriptor));
944         if (ret < 0) {
945                 message = "can't read hub descriptor";
946                 goto fail;
947         } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
948                 message = "hub has too many ports!";
949                 ret = -ENODEV;
950                 goto fail;
951         }
952
953         hdev->maxchild = hub->descriptor->bNbrPorts;
954         dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
955                 (hdev->maxchild == 1) ? "" : "s");
956
957         hub->port_owners = kzalloc(hdev->maxchild * sizeof(void *), GFP_KERNEL);
958         if (!hub->port_owners) {
959                 ret = -ENOMEM;
960                 goto fail;
961         }
962
963         wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
964
965         if (wHubCharacteristics & HUB_CHAR_COMPOUND) {
966                 int     i;
967                 char    portstr [USB_MAXCHILDREN + 1];
968
969                 for (i = 0; i < hdev->maxchild; i++)
970                         portstr[i] = hub->descriptor->DeviceRemovable
971                                     [((i + 1) / 8)] & (1 << ((i + 1) % 8))
972                                 ? 'F' : 'R';
973                 portstr[hdev->maxchild] = 0;
974                 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
975         } else
976                 dev_dbg(hub_dev, "standalone hub\n");
977
978         switch (wHubCharacteristics & HUB_CHAR_LPSM) {
979                 case 0x00:
980                         dev_dbg(hub_dev, "ganged power switching\n");
981                         break;
982                 case 0x01:
983                         dev_dbg(hub_dev, "individual port power switching\n");
984                         break;
985                 case 0x02:
986                 case 0x03:
987                         dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
988                         break;
989         }
990
991         switch (wHubCharacteristics & HUB_CHAR_OCPM) {
992                 case 0x00:
993                         dev_dbg(hub_dev, "global over-current protection\n");
994                         break;
995                 case 0x08:
996                         dev_dbg(hub_dev, "individual port over-current protection\n");
997                         break;
998                 case 0x10:
999                 case 0x18:
1000                         dev_dbg(hub_dev, "no over-current protection\n");
1001                         break;
1002         }
1003
1004         spin_lock_init (&hub->tt.lock);
1005         INIT_LIST_HEAD (&hub->tt.clear_list);
1006         INIT_WORK(&hub->tt.clear_work, hub_tt_work);
1007         switch (hdev->descriptor.bDeviceProtocol) {
1008                 case 0:
1009                         break;
1010                 case 1:
1011                         dev_dbg(hub_dev, "Single TT\n");
1012                         hub->tt.hub = hdev;
1013                         break;
1014                 case 2:
1015                         ret = usb_set_interface(hdev, 0, 1);
1016                         if (ret == 0) {
1017                                 dev_dbg(hub_dev, "TT per port\n");
1018                                 hub->tt.multi = 1;
1019                         } else
1020                                 dev_err(hub_dev, "Using single TT (err %d)\n",
1021                                         ret);
1022                         hub->tt.hub = hdev;
1023                         break;
1024                 case 3:
1025                         /* USB 3.0 hubs don't have a TT */
1026                         break;
1027                 default:
1028                         dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
1029                                 hdev->descriptor.bDeviceProtocol);
1030                         break;
1031         }
1032
1033         /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
1034         switch (wHubCharacteristics & HUB_CHAR_TTTT) {
1035                 case HUB_TTTT_8_BITS:
1036                         if (hdev->descriptor.bDeviceProtocol != 0) {
1037                                 hub->tt.think_time = 666;
1038                                 dev_dbg(hub_dev, "TT requires at most %d "
1039                                                 "FS bit times (%d ns)\n",
1040                                         8, hub->tt.think_time);
1041                         }
1042                         break;
1043                 case HUB_TTTT_16_BITS:
1044                         hub->tt.think_time = 666 * 2;
1045                         dev_dbg(hub_dev, "TT requires at most %d "
1046                                         "FS bit times (%d ns)\n",
1047                                 16, hub->tt.think_time);
1048                         break;
1049                 case HUB_TTTT_24_BITS:
1050                         hub->tt.think_time = 666 * 3;
1051                         dev_dbg(hub_dev, "TT requires at most %d "
1052                                         "FS bit times (%d ns)\n",
1053                                 24, hub->tt.think_time);
1054                         break;
1055                 case HUB_TTTT_32_BITS:
1056                         hub->tt.think_time = 666 * 4;
1057                         dev_dbg(hub_dev, "TT requires at most %d "
1058                                         "FS bit times (%d ns)\n",
1059                                 32, hub->tt.think_time);
1060                         break;
1061         }
1062
1063         /* probe() zeroes hub->indicator[] */
1064         if (wHubCharacteristics & HUB_CHAR_PORTIND) {
1065                 hub->has_indicators = 1;
1066                 dev_dbg(hub_dev, "Port indicators are supported\n");
1067         }
1068
1069         dev_dbg(hub_dev, "power on to power good time: %dms\n",
1070                 hub->descriptor->bPwrOn2PwrGood * 2);
1071
1072         /* power budgeting mostly matters with bus-powered hubs,
1073          * and battery-powered root hubs (may provide just 8 mA).
1074          */
1075         ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
1076         if (ret < 2) {
1077                 message = "can't get hub status";
1078                 goto fail;
1079         }
1080         le16_to_cpus(&hubstatus);
1081         if (hdev == hdev->bus->root_hub) {
1082                 if (hdev->bus_mA == 0 || hdev->bus_mA >= 500)
1083                         hub->mA_per_port = 500;
1084                 else {
1085                         hub->mA_per_port = hdev->bus_mA;
1086                         hub->limited_power = 1;
1087                 }
1088         } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
1089                 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
1090                         hub->descriptor->bHubContrCurrent);
1091                 hub->limited_power = 1;
1092                 if (hdev->maxchild > 0) {
1093                         int remaining = hdev->bus_mA -
1094                                         hub->descriptor->bHubContrCurrent;
1095
1096                         if (remaining < hdev->maxchild * 100)
1097                                 dev_warn(hub_dev,
1098                                         "insufficient power available "
1099                                         "to use all downstream ports\n");
1100                         hub->mA_per_port = 100;         /* 7.2.1.1 */
1101                 }
1102         } else {        /* Self-powered external hub */
1103                 /* FIXME: What about battery-powered external hubs that
1104                  * provide less current per port? */
1105                 hub->mA_per_port = 500;
1106         }
1107         if (hub->mA_per_port < 500)
1108                 dev_dbg(hub_dev, "%umA bus power budget for each child\n",
1109                                 hub->mA_per_port);
1110
1111         /* Update the HCD's internal representation of this hub before khubd
1112          * starts getting port status changes for devices under the hub.
1113          */
1114         hcd = bus_to_hcd(hdev->bus);
1115         if (hcd->driver->update_hub_device) {
1116                 ret = hcd->driver->update_hub_device(hcd, hdev,
1117                                 &hub->tt, GFP_KERNEL);
1118                 if (ret < 0) {
1119                         message = "can't update HCD hub info";
1120                         goto fail;
1121                 }
1122         }
1123
1124         ret = hub_hub_status(hub, &hubstatus, &hubchange);
1125         if (ret < 0) {
1126                 message = "can't get hub status";
1127                 goto fail;
1128         }
1129
1130         /* local power status reports aren't always correct */
1131         if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
1132                 dev_dbg(hub_dev, "local power source is %s\n",
1133                         (hubstatus & HUB_STATUS_LOCAL_POWER)
1134                         ? "lost (inactive)" : "good");
1135
1136         if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
1137                 dev_dbg(hub_dev, "%sover-current condition exists\n",
1138                         (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
1139
1140         /* set up the interrupt endpoint
1141          * We use the EP's maxpacket size instead of (PORTS+1+7)/8
1142          * bytes as USB2.0[11.12.3] says because some hubs are known
1143          * to send more data (and thus cause overflow). For root hubs,
1144          * maxpktsize is defined in hcd.c's fake endpoint descriptors
1145          * to be big enough for at least USB_MAXCHILDREN ports. */
1146         pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
1147         maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
1148
1149         if (maxp > sizeof(*hub->buffer))
1150                 maxp = sizeof(*hub->buffer);
1151
1152         hub->urb = usb_alloc_urb(0, GFP_KERNEL);
1153         if (!hub->urb) {
1154                 ret = -ENOMEM;
1155                 goto fail;
1156         }
1157
1158         usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
1159                 hub, endpoint->bInterval);
1160
1161         /* maybe cycle the hub leds */
1162         if (hub->has_indicators && blinkenlights)
1163                 hub->indicator [0] = INDICATOR_CYCLE;
1164
1165         hub_activate(hub, HUB_INIT);
1166         return 0;
1167
1168 fail:
1169         dev_err (hub_dev, "config failed, %s (err %d)\n",
1170                         message, ret);
1171         /* hub_disconnect() frees urb and descriptor */
1172         return ret;
1173 }
1174
1175 static void hub_release(struct kref *kref)
1176 {
1177         struct usb_hub *hub = container_of(kref, struct usb_hub, kref);
1178
1179         usb_put_intf(to_usb_interface(hub->intfdev));
1180         kfree(hub);
1181 }
1182
1183 static unsigned highspeed_hubs;
1184
1185 static void hub_disconnect(struct usb_interface *intf)
1186 {
1187         struct usb_hub *hub = usb_get_intfdata (intf);
1188
1189         /* Take the hub off the event list and don't let it be added again */
1190         spin_lock_irq(&hub_event_lock);
1191         if (!list_empty(&hub->event_list)) {
1192                 list_del_init(&hub->event_list);
1193                 usb_autopm_put_interface_no_suspend(intf);
1194         }
1195         hub->disconnected = 1;
1196         spin_unlock_irq(&hub_event_lock);
1197
1198         /* Disconnect all children and quiesce the hub */
1199         hub->error = 0;
1200         hub_quiesce(hub, HUB_DISCONNECT);
1201
1202         usb_set_intfdata (intf, NULL);
1203         hub->hdev->maxchild = 0;
1204
1205         if (hub->hdev->speed == USB_SPEED_HIGH)
1206                 highspeed_hubs--;
1207
1208         usb_free_urb(hub->urb);
1209         kfree(hub->port_owners);
1210         kfree(hub->descriptor);
1211         kfree(hub->status);
1212         kfree(hub->buffer);
1213
1214         kref_put(&hub->kref, hub_release);
1215 }
1216
1217 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
1218 {
1219         struct usb_host_interface *desc;
1220         struct usb_endpoint_descriptor *endpoint;
1221         struct usb_device *hdev;
1222         struct usb_hub *hub;
1223
1224         desc = intf->cur_altsetting;
1225         hdev = interface_to_usbdev(intf);
1226
1227         /* Hubs have proper suspend/resume support */
1228         usb_enable_autosuspend(hdev);
1229
1230         if (hdev->level == MAX_TOPO_LEVEL) {
1231                 dev_err(&intf->dev,
1232                         "Unsupported bus topology: hub nested too deep\n");
1233                 return -E2BIG;
1234         }
1235
1236 #ifdef  CONFIG_USB_OTG_BLACKLIST_HUB
1237         if (hdev->parent) {
1238                 dev_warn(&intf->dev, "ignoring external hub\n");
1239                 return -ENODEV;
1240         }
1241 #endif
1242
1243         /* Some hubs have a subclass of 1, which AFAICT according to the */
1244         /*  specs is not defined, but it works */
1245         if ((desc->desc.bInterfaceSubClass != 0) &&
1246             (desc->desc.bInterfaceSubClass != 1)) {
1247 descriptor_error:
1248                 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
1249                 return -EIO;
1250         }
1251
1252         /* Multiple endpoints? What kind of mutant ninja-hub is this? */
1253         if (desc->desc.bNumEndpoints != 1)
1254                 goto descriptor_error;
1255
1256         endpoint = &desc->endpoint[0].desc;
1257
1258         /* If it's not an interrupt in endpoint, we'd better punt! */
1259         if (!usb_endpoint_is_int_in(endpoint))
1260                 goto descriptor_error;
1261
1262         /* We found a hub */
1263         dev_info (&intf->dev, "USB hub found\n");
1264
1265         hub = kzalloc(sizeof(*hub), GFP_KERNEL);
1266         if (!hub) {
1267                 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
1268                 return -ENOMEM;
1269         }
1270
1271         kref_init(&hub->kref);
1272         INIT_LIST_HEAD(&hub->event_list);
1273         hub->intfdev = &intf->dev;
1274         hub->hdev = hdev;
1275         INIT_DELAYED_WORK(&hub->leds, led_work);
1276         INIT_DELAYED_WORK(&hub->init_work, NULL);
1277         usb_get_intf(intf);
1278
1279         usb_set_intfdata (intf, hub);
1280         intf->needs_remote_wakeup = 1;
1281
1282         if (hdev->speed == USB_SPEED_HIGH)
1283                 highspeed_hubs++;
1284
1285         if (hub_configure(hub, endpoint) >= 0)
1286                 return 0;
1287
1288         hub_disconnect (intf);
1289         return -ENODEV;
1290 }
1291
1292 static int
1293 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
1294 {
1295         struct usb_device *hdev = interface_to_usbdev (intf);
1296
1297         /* assert ifno == 0 (part of hub spec) */
1298         switch (code) {
1299         case USBDEVFS_HUB_PORTINFO: {
1300                 struct usbdevfs_hub_portinfo *info = user_data;
1301                 int i;
1302
1303                 spin_lock_irq(&device_state_lock);
1304                 if (hdev->devnum <= 0)
1305                         info->nports = 0;
1306                 else {
1307                         info->nports = hdev->maxchild;
1308                         for (i = 0; i < info->nports; i++) {
1309                                 if (hdev->children[i] == NULL)
1310                                         info->port[i] = 0;
1311                                 else
1312                                         info->port[i] =
1313                                                 hdev->children[i]->devnum;
1314                         }
1315                 }
1316                 spin_unlock_irq(&device_state_lock);
1317
1318                 return info->nports + 1;
1319                 }
1320
1321         default:
1322                 return -ENOSYS;
1323         }
1324 }
1325
1326 /*
1327  * Allow user programs to claim ports on a hub.  When a device is attached
1328  * to one of these "claimed" ports, the program will "own" the device.
1329  */
1330 static int find_port_owner(struct usb_device *hdev, unsigned port1,
1331                 void ***ppowner)
1332 {
1333         if (hdev->state == USB_STATE_NOTATTACHED)
1334                 return -ENODEV;
1335         if (port1 == 0 || port1 > hdev->maxchild)
1336                 return -EINVAL;
1337
1338         /* This assumes that devices not managed by the hub driver
1339          * will always have maxchild equal to 0.
1340          */
1341         *ppowner = &(hdev_to_hub(hdev)->port_owners[port1 - 1]);
1342         return 0;
1343 }
1344
1345 /* In the following three functions, the caller must hold hdev's lock */
1346 int usb_hub_claim_port(struct usb_device *hdev, unsigned port1, void *owner)
1347 {
1348         int rc;
1349         void **powner;
1350
1351         rc = find_port_owner(hdev, port1, &powner);
1352         if (rc)
1353                 return rc;
1354         if (*powner)
1355                 return -EBUSY;
1356         *powner = owner;
1357         return rc;
1358 }
1359
1360 int usb_hub_release_port(struct usb_device *hdev, unsigned port1, void *owner)
1361 {
1362         int rc;
1363         void **powner;
1364
1365         rc = find_port_owner(hdev, port1, &powner);
1366         if (rc)
1367                 return rc;
1368         if (*powner != owner)
1369                 return -ENOENT;
1370         *powner = NULL;
1371         return rc;
1372 }
1373
1374 void usb_hub_release_all_ports(struct usb_device *hdev, void *owner)
1375 {
1376         int n;
1377         void **powner;
1378
1379         n = find_port_owner(hdev, 1, &powner);
1380         if (n == 0) {
1381                 for (; n < hdev->maxchild; (++n, ++powner)) {
1382                         if (*powner == owner)
1383                                 *powner = NULL;
1384                 }
1385         }
1386 }
1387
1388 /* The caller must hold udev's lock */
1389 bool usb_device_is_owned(struct usb_device *udev)
1390 {
1391         struct usb_hub *hub;
1392
1393         if (udev->state == USB_STATE_NOTATTACHED || !udev->parent)
1394                 return false;
1395         hub = hdev_to_hub(udev->parent);
1396         return !!hub->port_owners[udev->portnum - 1];
1397 }
1398
1399
1400 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
1401 {
1402         int i;
1403
1404         for (i = 0; i < udev->maxchild; ++i) {
1405                 if (udev->children[i])
1406                         recursively_mark_NOTATTACHED(udev->children[i]);
1407         }
1408         if (udev->state == USB_STATE_SUSPENDED) {
1409                 udev->discon_suspended = 1;
1410                 udev->active_duration -= jiffies;
1411         }
1412         udev->state = USB_STATE_NOTATTACHED;
1413 }
1414
1415 /**
1416  * usb_set_device_state - change a device's current state (usbcore, hcds)
1417  * @udev: pointer to device whose state should be changed
1418  * @new_state: new state value to be stored
1419  *
1420  * udev->state is _not_ fully protected by the device lock.  Although
1421  * most transitions are made only while holding the lock, the state can
1422  * can change to USB_STATE_NOTATTACHED at almost any time.  This
1423  * is so that devices can be marked as disconnected as soon as possible,
1424  * without having to wait for any semaphores to be released.  As a result,
1425  * all changes to any device's state must be protected by the
1426  * device_state_lock spinlock.
1427  *
1428  * Once a device has been added to the device tree, all changes to its state
1429  * should be made using this routine.  The state should _not_ be set directly.
1430  *
1431  * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1432  * Otherwise udev->state is set to new_state, and if new_state is
1433  * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1434  * to USB_STATE_NOTATTACHED.
1435  */
1436 void usb_set_device_state(struct usb_device *udev,
1437                 enum usb_device_state new_state)
1438 {
1439         unsigned long flags;
1440
1441         spin_lock_irqsave(&device_state_lock, flags);
1442         if (udev->state == USB_STATE_NOTATTACHED)
1443                 ;       /* do nothing */
1444         else if (new_state != USB_STATE_NOTATTACHED) {
1445
1446                 /* root hub wakeup capabilities are managed out-of-band
1447                  * and may involve silicon errata ... ignore them here.
1448                  */
1449                 if (udev->parent) {
1450                         if (udev->state == USB_STATE_SUSPENDED
1451                                         || new_state == USB_STATE_SUSPENDED)
1452                                 ;       /* No change to wakeup settings */
1453                         else if (new_state == USB_STATE_CONFIGURED)
1454                                 device_set_wakeup_capable(&udev->dev,
1455                                         (udev->actconfig->desc.bmAttributes
1456                                          & USB_CONFIG_ATT_WAKEUP));
1457                         else
1458                                 device_set_wakeup_capable(&udev->dev, 0);
1459                 }
1460                 if (udev->state == USB_STATE_SUSPENDED &&
1461                         new_state != USB_STATE_SUSPENDED)
1462                         udev->active_duration -= jiffies;
1463                 else if (new_state == USB_STATE_SUSPENDED &&
1464                                 udev->state != USB_STATE_SUSPENDED)
1465                         udev->active_duration += jiffies;
1466                 udev->state = new_state;
1467         } else
1468                 recursively_mark_NOTATTACHED(udev);
1469         spin_unlock_irqrestore(&device_state_lock, flags);
1470 }
1471 EXPORT_SYMBOL_GPL(usb_set_device_state);
1472
1473 /*
1474  * WUSB devices are simple: they have no hubs behind, so the mapping
1475  * device <-> virtual port number becomes 1:1. Why? to simplify the
1476  * life of the device connection logic in
1477  * drivers/usb/wusbcore/devconnect.c. When we do the initial secret
1478  * handshake we need to assign a temporary address in the unauthorized
1479  * space. For simplicity we use the first virtual port number found to
1480  * be free [drivers/usb/wusbcore/devconnect.c:wusbhc_devconnect_ack()]
1481  * and that becomes it's address [X < 128] or its unauthorized address
1482  * [X | 0x80].
1483  *
1484  * We add 1 as an offset to the one-based USB-stack port number
1485  * (zero-based wusb virtual port index) for two reasons: (a) dev addr
1486  * 0 is reserved by USB for default address; (b) Linux's USB stack
1487  * uses always #1 for the root hub of the controller. So USB stack's
1488  * port #1, which is wusb virtual-port #0 has address #2.
1489  *
1490  * Devices connected under xHCI are not as simple.  The host controller
1491  * supports virtualization, so the hardware assigns device addresses and
1492  * the HCD must setup data structures before issuing a set address
1493  * command to the hardware.
1494  */
1495 static void choose_address(struct usb_device *udev)
1496 {
1497         int             devnum;
1498         struct usb_bus  *bus = udev->bus;
1499
1500         /* If khubd ever becomes multithreaded, this will need a lock */
1501         if (udev->wusb) {
1502                 devnum = udev->portnum + 1;
1503                 BUG_ON(test_bit(devnum, bus->devmap.devicemap));
1504         } else {
1505                 /* Try to allocate the next devnum beginning at
1506                  * bus->devnum_next. */
1507                 devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1508                                             bus->devnum_next);
1509                 if (devnum >= 128)
1510                         devnum = find_next_zero_bit(bus->devmap.devicemap,
1511                                                     128, 1);
1512                 bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1513         }
1514         if (devnum < 128) {
1515                 set_bit(devnum, bus->devmap.devicemap);
1516                 udev->devnum = devnum;
1517         }
1518 }
1519
1520 static void release_address(struct usb_device *udev)
1521 {
1522         if (udev->devnum > 0) {
1523                 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1524                 udev->devnum = -1;
1525         }
1526 }
1527
1528 static void update_address(struct usb_device *udev, int devnum)
1529 {
1530         /* The address for a WUSB device is managed by wusbcore. */
1531         if (!udev->wusb)
1532                 udev->devnum = devnum;
1533 }
1534
1535 #ifdef  CONFIG_USB_SUSPEND
1536
1537 static void usb_stop_pm(struct usb_device *udev)
1538 {
1539         /* Synchronize with the ksuspend thread to prevent any more
1540          * autosuspend requests from being submitted, and decrement
1541          * the parent's count of unsuspended children.
1542          */
1543         usb_pm_lock(udev);
1544         if (udev->parent && !udev->discon_suspended)
1545                 usb_autosuspend_device(udev->parent);
1546         usb_pm_unlock(udev);
1547
1548         /* Stop any autosuspend or autoresume requests already submitted */
1549         cancel_delayed_work_sync(&udev->autosuspend);
1550         cancel_work_sync(&udev->autoresume);
1551 }
1552
1553 #else
1554
1555 static inline void usb_stop_pm(struct usb_device *udev)
1556 { }
1557
1558 #endif
1559
1560 /**
1561  * usb_disconnect - disconnect a device (usbcore-internal)
1562  * @pdev: pointer to device being disconnected
1563  * Context: !in_interrupt ()
1564  *
1565  * Something got disconnected. Get rid of it and all of its children.
1566  *
1567  * If *pdev is a normal device then the parent hub must already be locked.
1568  * If *pdev is a root hub then this routine will acquire the
1569  * usb_bus_list_lock on behalf of the caller.
1570  *
1571  * Only hub drivers (including virtual root hub drivers for host
1572  * controllers) should ever call this.
1573  *
1574  * This call is synchronous, and may not be used in an interrupt context.
1575  */
1576 void usb_disconnect(struct usb_device **pdev)
1577 {
1578         struct usb_device       *udev = *pdev;
1579         int                     i;
1580
1581         if (!udev) {
1582                 pr_debug ("%s nodev\n", __func__);
1583                 return;
1584         }
1585
1586         /* mark the device as inactive, so any further urb submissions for
1587          * this device (and any of its children) will fail immediately.
1588          * this quiesces everyting except pending urbs.
1589          */
1590         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1591         dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1592
1593         usb_lock_device(udev);
1594
1595         /* Free up all the children before we remove this device */
1596         for (i = 0; i < USB_MAXCHILDREN; i++) {
1597                 if (udev->children[i])
1598                         usb_disconnect(&udev->children[i]);
1599         }
1600
1601         /* deallocate hcd/hardware state ... nuking all pending urbs and
1602          * cleaning up all state associated with the current configuration
1603          * so that the hardware is now fully quiesced.
1604          */
1605         dev_dbg (&udev->dev, "unregistering device\n");
1606         usb_disable_device(udev, 0);
1607         usb_hcd_synchronize_unlinks(udev);
1608
1609         usb_remove_ep_devs(&udev->ep0);
1610         usb_unlock_device(udev);
1611
1612         /* Unregister the device.  The device driver is responsible
1613          * for de-configuring the device and invoking the remove-device
1614          * notifier chain (used by usbfs and possibly others).
1615          */
1616         device_del(&udev->dev);
1617
1618         /* Free the device number and delete the parent's children[]
1619          * (or root_hub) pointer.
1620          */
1621         release_address(udev);
1622
1623         /* Avoid races with recursively_mark_NOTATTACHED() */
1624         spin_lock_irq(&device_state_lock);
1625         *pdev = NULL;
1626         spin_unlock_irq(&device_state_lock);
1627
1628         usb_stop_pm(udev);
1629
1630         put_device(&udev->dev);
1631 }
1632
1633 #ifdef CONFIG_USB_ANNOUNCE_NEW_DEVICES
1634 static void show_string(struct usb_device *udev, char *id, char *string)
1635 {
1636         if (!string)
1637                 return;
1638         dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1639 }
1640
1641 static void announce_device(struct usb_device *udev)
1642 {
1643         dev_info(&udev->dev, "New USB device found, idVendor=%04x, idProduct=%04x\n",
1644                 le16_to_cpu(udev->descriptor.idVendor),
1645                 le16_to_cpu(udev->descriptor.idProduct));
1646         dev_info(&udev->dev,
1647                 "New USB device strings: Mfr=%d, Product=%d, SerialNumber=%d\n",
1648                 udev->descriptor.iManufacturer,
1649                 udev->descriptor.iProduct,
1650                 udev->descriptor.iSerialNumber);
1651         show_string(udev, "Product", udev->product);
1652         show_string(udev, "Manufacturer", udev->manufacturer);
1653         show_string(udev, "SerialNumber", udev->serial);
1654 }
1655 #else
1656 static inline void announce_device(struct usb_device *udev) { }
1657 #endif
1658
1659 #ifdef  CONFIG_USB_OTG
1660 #include "otg_whitelist.h"
1661 #endif
1662
1663 /**
1664  * usb_enumerate_device_otg - FIXME (usbcore-internal)
1665  * @udev: newly addressed device (in ADDRESS state)
1666  *
1667  * Finish enumeration for On-The-Go devices
1668  */
1669 static int usb_enumerate_device_otg(struct usb_device *udev)
1670 {
1671         int err = 0;
1672
1673 #ifdef  CONFIG_USB_OTG
1674         /*
1675          * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1676          * to wake us after we've powered off VBUS; and HNP, switching roles
1677          * "host" to "peripheral".  The OTG descriptor helps figure this out.
1678          */
1679         if (!udev->bus->is_b_host
1680                         && udev->config
1681                         && udev->parent == udev->bus->root_hub) {
1682                 struct usb_otg_descriptor       *desc = NULL;
1683                 struct usb_bus                  *bus = udev->bus;
1684
1685                 /* descriptor may appear anywhere in config */
1686                 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1687                                         le16_to_cpu(udev->config[0].desc.wTotalLength),
1688                                         USB_DT_OTG, (void **) &desc) == 0) {
1689                         if (desc->bmAttributes & USB_OTG_HNP) {
1690                                 unsigned                port1 = udev->portnum;
1691
1692                                 dev_info(&udev->dev,
1693                                         "Dual-Role OTG device on %sHNP port\n",
1694                                         (port1 == bus->otg_port)
1695                                                 ? "" : "non-");
1696
1697                                 /* enable HNP before suspend, it's simpler */
1698                                 if (port1 == bus->otg_port)
1699                                         bus->b_hnp_enable = 1;
1700                                 err = usb_control_msg(udev,
1701                                         usb_sndctrlpipe(udev, 0),
1702                                         USB_REQ_SET_FEATURE, 0,
1703                                         bus->b_hnp_enable
1704                                                 ? USB_DEVICE_B_HNP_ENABLE
1705                                                 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1706                                         0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1707                                 if (err < 0) {
1708                                         /* OTG MESSAGE: report errors here,
1709                                          * customize to match your product.
1710                                          */
1711                                         dev_info(&udev->dev,
1712                                                 "can't set HNP mode: %d\n",
1713                                                 err);
1714                                         bus->b_hnp_enable = 0;
1715                                 }
1716                         }
1717                 }
1718         }
1719
1720         if (!is_targeted(udev)) {
1721
1722                 /* Maybe it can talk to us, though we can't talk to it.
1723                  * (Includes HNP test device.)
1724                  */
1725                 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1726                         err = usb_port_suspend(udev, PMSG_SUSPEND);
1727                         if (err < 0)
1728                                 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1729                 }
1730                 err = -ENOTSUPP;
1731                 goto fail;
1732         }
1733 fail:
1734 #endif
1735         return err;
1736 }
1737
1738
1739 /**
1740  * usb_enumerate_device - Read device configs/intfs/otg (usbcore-internal)
1741  * @udev: newly addressed device (in ADDRESS state)
1742  *
1743  * This is only called by usb_new_device() and usb_authorize_device()
1744  * and FIXME -- all comments that apply to them apply here wrt to
1745  * environment.
1746  *
1747  * If the device is WUSB and not authorized, we don't attempt to read
1748  * the string descriptors, as they will be errored out by the device
1749  * until it has been authorized.
1750  */
1751 static int usb_enumerate_device(struct usb_device *udev)
1752 {
1753         int err;
1754
1755         if (udev->config == NULL) {
1756                 err = usb_get_configuration(udev);
1757                 if (err < 0) {
1758                         dev_err(&udev->dev, "can't read configurations, error %d\n",
1759                                 err);
1760                         goto fail;
1761                 }
1762         }
1763         if (udev->wusb == 1 && udev->authorized == 0) {
1764                 udev->product = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1765                 udev->manufacturer = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1766                 udev->serial = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1767         }
1768         else {
1769                 /* read the standard strings and cache them if present */
1770                 udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
1771                 udev->manufacturer = usb_cache_string(udev,
1772                                                       udev->descriptor.iManufacturer);
1773                 udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
1774         }
1775         err = usb_enumerate_device_otg(udev);
1776 fail:
1777         return err;
1778 }
1779
1780
1781 /**
1782  * usb_new_device - perform initial device setup (usbcore-internal)
1783  * @udev: newly addressed device (in ADDRESS state)
1784  *
1785  * This is called with devices which have been detected but not fully
1786  * enumerated.  The device descriptor is available, but not descriptors
1787  * for any device configuration.  The caller must have locked either
1788  * the parent hub (if udev is a normal device) or else the
1789  * usb_bus_list_lock (if udev is a root hub).  The parent's pointer to
1790  * udev has already been installed, but udev is not yet visible through
1791  * sysfs or other filesystem code.
1792  *
1793  * It will return if the device is configured properly or not.  Zero if
1794  * the interface was registered with the driver core; else a negative
1795  * errno value.
1796  *
1797  * This call is synchronous, and may not be used in an interrupt context.
1798  *
1799  * Only the hub driver or root-hub registrar should ever call this.
1800  */
1801 int usb_new_device(struct usb_device *udev)
1802 {
1803         int err;
1804
1805         if (udev->parent) {
1806                 /* Increment the parent's count of unsuspended children */
1807                 usb_autoresume_device(udev->parent);
1808
1809                 /* Initialize non-root-hub device wakeup to disabled;
1810                  * device (un)configuration controls wakeup capable
1811                  * sysfs power/wakeup controls wakeup enabled/disabled
1812                  */
1813                 device_init_wakeup(&udev->dev, 0);
1814                 device_set_wakeup_enable(&udev->dev, 1);
1815         }
1816
1817         usb_detect_quirks(udev);
1818         err = usb_enumerate_device(udev);       /* Read descriptors */
1819         if (err < 0)
1820                 goto fail;
1821         dev_dbg(&udev->dev, "udev %d, busnum %d, minor = %d\n",
1822                         udev->devnum, udev->bus->busnum,
1823                         (((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
1824         /* export the usbdev device-node for libusb */
1825         udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
1826                         (((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
1827
1828         /* Tell the world! */
1829         announce_device(udev);
1830
1831         device_enable_async_suspend(&udev->dev);
1832         /* Register the device.  The device driver is responsible
1833          * for configuring the device and invoking the add-device
1834          * notifier chain (used by usbfs and possibly others).
1835          */
1836         err = device_add(&udev->dev);
1837         if (err) {
1838                 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1839                 goto fail;
1840         }
1841
1842         (void) usb_create_ep_devs(&udev->dev, &udev->ep0, udev);
1843         return err;
1844
1845 fail:
1846         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1847         usb_stop_pm(udev);
1848         return err;
1849 }
1850
1851
1852 /**
1853  * usb_deauthorize_device - deauthorize a device (usbcore-internal)
1854  * @usb_dev: USB device
1855  *
1856  * Move the USB device to a very basic state where interfaces are disabled
1857  * and the device is in fact unconfigured and unusable.
1858  *
1859  * We share a lock (that we have) with device_del(), so we need to
1860  * defer its call.
1861  */
1862 int usb_deauthorize_device(struct usb_device *usb_dev)
1863 {
1864         usb_lock_device(usb_dev);
1865         if (usb_dev->authorized == 0)
1866                 goto out_unauthorized;
1867
1868         usb_dev->authorized = 0;
1869         usb_set_configuration(usb_dev, -1);
1870
1871         kfree(usb_dev->product);
1872         usb_dev->product = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1873         kfree(usb_dev->manufacturer);
1874         usb_dev->manufacturer = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1875         kfree(usb_dev->serial);
1876         usb_dev->serial = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1877
1878         usb_destroy_configuration(usb_dev);
1879         usb_dev->descriptor.bNumConfigurations = 0;
1880
1881 out_unauthorized:
1882         usb_unlock_device(usb_dev);
1883         return 0;
1884 }
1885
1886
1887 int usb_authorize_device(struct usb_device *usb_dev)
1888 {
1889         int result = 0, c;
1890
1891         usb_lock_device(usb_dev);
1892         if (usb_dev->authorized == 1)
1893                 goto out_authorized;
1894
1895         result = usb_autoresume_device(usb_dev);
1896         if (result < 0) {
1897                 dev_err(&usb_dev->dev,
1898                         "can't autoresume for authorization: %d\n", result);
1899                 goto error_autoresume;
1900         }
1901         result = usb_get_device_descriptor(usb_dev, sizeof(usb_dev->descriptor));
1902         if (result < 0) {
1903                 dev_err(&usb_dev->dev, "can't re-read device descriptor for "
1904                         "authorization: %d\n", result);
1905                 goto error_device_descriptor;
1906         }
1907
1908         kfree(usb_dev->product);
1909         usb_dev->product = NULL;
1910         kfree(usb_dev->manufacturer);
1911         usb_dev->manufacturer = NULL;
1912         kfree(usb_dev->serial);
1913         usb_dev->serial = NULL;
1914
1915         usb_dev->authorized = 1;
1916         result = usb_enumerate_device(usb_dev);
1917         if (result < 0)
1918                 goto error_enumerate;
1919         /* Choose and set the configuration.  This registers the interfaces
1920          * with the driver core and lets interface drivers bind to them.
1921          */
1922         c = usb_choose_configuration(usb_dev);
1923         if (c >= 0) {
1924                 result = usb_set_configuration(usb_dev, c);
1925                 if (result) {
1926                         dev_err(&usb_dev->dev,
1927                                 "can't set config #%d, error %d\n", c, result);
1928                         /* This need not be fatal.  The user can try to
1929                          * set other configurations. */
1930                 }
1931         }
1932         dev_info(&usb_dev->dev, "authorized to connect\n");
1933
1934 error_enumerate:
1935 error_device_descriptor:
1936         usb_autosuspend_device(usb_dev);
1937 error_autoresume:
1938 out_authorized:
1939         usb_unlock_device(usb_dev);     // complements locktree
1940         return result;
1941 }
1942
1943
1944 /* Returns 1 if @hub is a WUSB root hub, 0 otherwise */
1945 static unsigned hub_is_wusb(struct usb_hub *hub)
1946 {
1947         struct usb_hcd *hcd;
1948         if (hub->hdev->parent != NULL)  /* not a root hub? */
1949                 return 0;
1950         hcd = container_of(hub->hdev->bus, struct usb_hcd, self);
1951         return hcd->wireless;
1952 }
1953
1954
1955 #define PORT_RESET_TRIES        5
1956 #define SET_ADDRESS_TRIES       2
1957 #define GET_DESCRIPTOR_TRIES    2
1958 #define SET_CONFIG_TRIES        (2 * (use_both_schemes + 1))
1959 #define USE_NEW_SCHEME(i)       ((i) / 2 == old_scheme_first)
1960
1961 #define HUB_ROOT_RESET_TIME     50      /* times are in msec */
1962 #define HUB_SHORT_RESET_TIME    10
1963 #define HUB_LONG_RESET_TIME     200
1964 #define HUB_RESET_TIMEOUT       500
1965
1966 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1967                                 struct usb_device *udev, unsigned int delay)
1968 {
1969         int delay_time, ret;
1970         u16 portstatus;
1971         u16 portchange;
1972
1973         for (delay_time = 0;
1974                         delay_time < HUB_RESET_TIMEOUT;
1975                         delay_time += delay) {
1976                 /* wait to give the device a chance to reset */
1977                 msleep(delay);
1978
1979                 /* read and decode port status */
1980                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1981                 if (ret < 0)
1982                         return ret;
1983
1984                 /* Device went away? */
1985                 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1986                         return -ENOTCONN;
1987
1988                 /* bomb out completely if the connection bounced */
1989                 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1990                         return -ENOTCONN;
1991
1992                 /* if we`ve finished resetting, then break out of the loop */
1993                 if (!(portstatus & USB_PORT_STAT_RESET) &&
1994                     (portstatus & USB_PORT_STAT_ENABLE)) {
1995                         if (hub_is_wusb(hub))
1996                                 udev->speed = USB_SPEED_WIRELESS;
1997                         else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1998                                 udev->speed = USB_SPEED_HIGH;
1999                         else if (portstatus & USB_PORT_STAT_LOW_SPEED)
2000                                 udev->speed = USB_SPEED_LOW;
2001                         else
2002                                 udev->speed = USB_SPEED_FULL;
2003                         return 0;
2004                 }
2005
2006                 /* switch to the long delay after two short delay failures */
2007                 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
2008                         delay = HUB_LONG_RESET_TIME;
2009
2010                 dev_dbg (hub->intfdev,
2011                         "port %d not reset yet, waiting %dms\n",
2012                         port1, delay);
2013         }
2014
2015         return -EBUSY;
2016 }
2017
2018 static int hub_port_reset(struct usb_hub *hub, int port1,
2019                                 struct usb_device *udev, unsigned int delay)
2020 {
2021         int i, status;
2022         struct usb_hcd *hcd;
2023
2024         hcd = bus_to_hcd(udev->bus);
2025         /* Block EHCI CF initialization during the port reset.
2026          * Some companion controllers don't like it when they mix.
2027          */
2028         down_read(&ehci_cf_port_reset_rwsem);
2029
2030         /* Reset the port */
2031         for (i = 0; i < PORT_RESET_TRIES; i++) {
2032                 status = set_port_feature(hub->hdev,
2033                                 port1, USB_PORT_FEAT_RESET);
2034                 if (status)
2035                         dev_err(hub->intfdev,
2036                                         "cannot reset port %d (err = %d)\n",
2037                                         port1, status);
2038                 else {
2039                         status = hub_port_wait_reset(hub, port1, udev, delay);
2040                         if (status && status != -ENOTCONN)
2041                                 dev_dbg(hub->intfdev,
2042                                                 "port_wait_reset: err = %d\n",
2043                                                 status);
2044                 }
2045
2046                 /* return on disconnect or reset */
2047                 switch (status) {
2048                 case 0:
2049                         /* TRSTRCY = 10 ms; plus some extra */
2050                         msleep(10 + 40);
2051                         update_address(udev, 0);
2052                         if (hcd->driver->reset_device) {
2053                                 status = hcd->driver->reset_device(hcd, udev);
2054                                 if (status < 0) {
2055                                         dev_err(&udev->dev, "Cannot reset "
2056                                                         "HCD device state\n");
2057                                         break;
2058                                 }
2059                         }
2060                         /* FALL THROUGH */
2061                 case -ENOTCONN:
2062                 case -ENODEV:
2063                         clear_port_feature(hub->hdev,
2064                                 port1, USB_PORT_FEAT_C_RESET);
2065                         /* FIXME need disconnect() for NOTATTACHED device */
2066                         usb_set_device_state(udev, status
2067                                         ? USB_STATE_NOTATTACHED
2068                                         : USB_STATE_DEFAULT);
2069                         goto done;
2070                 }
2071
2072                 dev_dbg (hub->intfdev,
2073                         "port %d not enabled, trying reset again...\n",
2074                         port1);
2075                 delay = HUB_LONG_RESET_TIME;
2076         }
2077
2078         dev_err (hub->intfdev,
2079                 "Cannot enable port %i.  Maybe the USB cable is bad?\n",
2080                 port1);
2081
2082  done:
2083         up_read(&ehci_cf_port_reset_rwsem);
2084         return status;
2085 }
2086
2087 #ifdef  CONFIG_PM
2088
2089 #define MASK_BITS       (USB_PORT_STAT_POWER | USB_PORT_STAT_CONNECTION | \
2090                                 USB_PORT_STAT_SUSPEND)
2091 #define WANT_BITS       (USB_PORT_STAT_POWER | USB_PORT_STAT_CONNECTION)
2092
2093 /* Determine whether the device on a port is ready for a normal resume,
2094  * is ready for a reset-resume, or should be disconnected.
2095  */
2096 static int check_port_resume_type(struct usb_device *udev,
2097                 struct usb_hub *hub, int port1,
2098                 int status, unsigned portchange, unsigned portstatus)
2099 {
2100         /* Is the device still present? */
2101         if (status || (portstatus & MASK_BITS) != WANT_BITS) {
2102                 if (status >= 0)
2103                         status = -ENODEV;
2104         }
2105
2106         /* Can't do a normal resume if the port isn't enabled,
2107          * so try a reset-resume instead.
2108          */
2109         else if (!(portstatus & USB_PORT_STAT_ENABLE) && !udev->reset_resume) {
2110                 if (udev->persist_enabled)
2111                         udev->reset_resume = 1;
2112                 else
2113                         status = -ENODEV;
2114         }
2115
2116         if (status) {
2117                 dev_dbg(hub->intfdev,
2118                                 "port %d status %04x.%04x after resume, %d\n",
2119                                 port1, portchange, portstatus, status);
2120         } else if (udev->reset_resume) {
2121
2122                 /* Late port handoff can set status-change bits */
2123                 if (portchange & USB_PORT_STAT_C_CONNECTION)
2124                         clear_port_feature(hub->hdev, port1,
2125                                         USB_PORT_FEAT_C_CONNECTION);
2126                 if (portchange & USB_PORT_STAT_C_ENABLE)
2127                         clear_port_feature(hub->hdev, port1,
2128                                         USB_PORT_FEAT_C_ENABLE);
2129         }
2130
2131         return status;
2132 }
2133
2134 #ifdef  CONFIG_USB_SUSPEND
2135
2136 /*
2137  * usb_port_suspend - suspend a usb device's upstream port
2138  * @udev: device that's no longer in active use, not a root hub
2139  * Context: must be able to sleep; device not locked; pm locks held
2140  *
2141  * Suspends a USB device that isn't in active use, conserving power.
2142  * Devices may wake out of a suspend, if anything important happens,
2143  * using the remote wakeup mechanism.  They may also be taken out of
2144  * suspend by the host, using usb_port_resume().  It's also routine
2145  * to disconnect devices while they are suspended.
2146  *
2147  * This only affects the USB hardware for a device; its interfaces
2148  * (and, for hubs, child devices) must already have been suspended.
2149  *
2150  * Selective port suspend reduces power; most suspended devices draw
2151  * less than 500 uA.  It's also used in OTG, along with remote wakeup.
2152  * All devices below the suspended port are also suspended.
2153  *
2154  * Devices leave suspend state when the host wakes them up.  Some devices
2155  * also support "remote wakeup", where the device can activate the USB
2156  * tree above them to deliver data, such as a keypress or packet.  In
2157  * some cases, this wakes the USB host.
2158  *
2159  * Suspending OTG devices may trigger HNP, if that's been enabled
2160  * between a pair of dual-role devices.  That will change roles, such
2161  * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
2162  *
2163  * Devices on USB hub ports have only one "suspend" state, corresponding
2164  * to ACPI D2, "may cause the device to lose some context".
2165  * State transitions include:
2166  *
2167  *   - suspend, resume ... when the VBUS power link stays live
2168  *   - suspend, disconnect ... VBUS lost
2169  *
2170  * Once VBUS drop breaks the circuit, the port it's using has to go through
2171  * normal re-enumeration procedures, starting with enabling VBUS power.
2172  * Other than re-initializing the hub (plug/unplug, except for root hubs),
2173  * Linux (2.6) currently has NO mechanisms to initiate that:  no khubd
2174  * timer, no SRP, no requests through sysfs.
2175  *
2176  * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
2177  * the root hub for their bus goes into global suspend ... so we don't
2178  * (falsely) update the device power state to say it suspended.
2179  *
2180  * Returns 0 on success, else negative errno.
2181  */
2182 int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
2183 {
2184         struct usb_hub  *hub = hdev_to_hub(udev->parent);
2185         int             port1 = udev->portnum;
2186         int             status;
2187
2188         // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
2189
2190         /* enable remote wakeup when appropriate; this lets the device
2191          * wake up the upstream hub (including maybe the root hub).
2192          *
2193          * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
2194          * we don't explicitly enable it here.
2195          */
2196         if (udev->do_remote_wakeup) {
2197                 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2198                                 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
2199                                 USB_DEVICE_REMOTE_WAKEUP, 0,
2200                                 NULL, 0,
2201                                 USB_CTRL_SET_TIMEOUT);
2202                 if (status) {
2203                         dev_dbg(&udev->dev, "won't remote wakeup, status %d\n",
2204                                         status);
2205                         /* bail if autosuspend is requested */
2206                         if (msg.event & PM_EVENT_AUTO)
2207                                 return status;
2208                 }
2209         }
2210
2211         /* see 7.1.7.6 */
2212         status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
2213         if (status) {
2214                 dev_dbg(hub->intfdev, "can't suspend port %d, status %d\n",
2215                                 port1, status);
2216                 /* paranoia:  "should not happen" */
2217                 if (udev->do_remote_wakeup)
2218                         (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2219                                 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
2220                                 USB_DEVICE_REMOTE_WAKEUP, 0,
2221                                 NULL, 0,
2222                                 USB_CTRL_SET_TIMEOUT);
2223         } else {
2224                 /* device has up to 10 msec to fully suspend */
2225                 dev_dbg(&udev->dev, "usb %ssuspend\n",
2226                                 (msg.event & PM_EVENT_AUTO ? "auto-" : ""));
2227                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
2228                 msleep(10);
2229         }
2230         return status;
2231 }
2232
2233 /*
2234  * If the USB "suspend" state is in use (rather than "global suspend"),
2235  * many devices will be individually taken out of suspend state using
2236  * special "resume" signaling.  This routine kicks in shortly after
2237  * hardware resume signaling is finished, either because of selective
2238  * resume (by host) or remote wakeup (by device) ... now see what changed
2239  * in the tree that's rooted at this device.
2240  *
2241  * If @udev->reset_resume is set then the device is reset before the
2242  * status check is done.
2243  */
2244 static int finish_port_resume(struct usb_device *udev)
2245 {
2246         int     status = 0;
2247         u16     devstatus;
2248
2249         /* caller owns the udev device lock */
2250         dev_dbg(&udev->dev, "%s\n",
2251                 udev->reset_resume ? "finish reset-resume" : "finish resume");
2252
2253         /* usb ch9 identifies four variants of SUSPENDED, based on what
2254          * state the device resumes to.  Linux currently won't see the
2255          * first two on the host side; they'd be inside hub_port_init()
2256          * during many timeouts, but khubd can't suspend until later.
2257          */
2258         usb_set_device_state(udev, udev->actconfig
2259                         ? USB_STATE_CONFIGURED
2260                         : USB_STATE_ADDRESS);
2261
2262         /* 10.5.4.5 says not to reset a suspended port if the attached
2263          * device is enabled for remote wakeup.  Hence the reset
2264          * operation is carried out here, after the port has been
2265          * resumed.
2266          */
2267         if (udev->reset_resume)
2268  retry_reset_resume:
2269                 status = usb_reset_and_verify_device(udev);
2270
2271         /* 10.5.4.5 says be sure devices in the tree are still there.
2272          * For now let's assume the device didn't go crazy on resume,
2273          * and device drivers will know about any resume quirks.
2274          */
2275         if (status == 0) {
2276                 devstatus = 0;
2277                 status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
2278                 if (status >= 0)
2279                         status = (status > 0 ? 0 : -ENODEV);
2280
2281                 /* If a normal resume failed, try doing a reset-resume */
2282                 if (status && !udev->reset_resume && udev->persist_enabled) {
2283                         dev_dbg(&udev->dev, "retry with reset-resume\n");
2284                         udev->reset_resume = 1;
2285                         goto retry_reset_resume;
2286                 }
2287         }
2288
2289         if (status) {
2290                 dev_dbg(&udev->dev, "gone after usb resume? status %d\n",
2291                                 status);
2292         } else if (udev->actconfig) {
2293                 le16_to_cpus(&devstatus);
2294                 if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
2295                         status = usb_control_msg(udev,
2296                                         usb_sndctrlpipe(udev, 0),
2297                                         USB_REQ_CLEAR_FEATURE,
2298                                                 USB_RECIP_DEVICE,
2299                                         USB_DEVICE_REMOTE_WAKEUP, 0,
2300                                         NULL, 0,
2301                                         USB_CTRL_SET_TIMEOUT);
2302                         if (status)
2303                                 dev_dbg(&udev->dev,
2304                                         "disable remote wakeup, status %d\n",
2305                                         status);
2306                 }
2307                 status = 0;
2308         }
2309         return status;
2310 }
2311
2312 /*
2313  * usb_port_resume - re-activate a suspended usb device's upstream port
2314  * @udev: device to re-activate, not a root hub
2315  * Context: must be able to sleep; device not locked; pm locks held
2316  *
2317  * This will re-activate the suspended device, increasing power usage
2318  * while letting drivers communicate again with its endpoints.
2319  * USB resume explicitly guarantees that the power session between
2320  * the host and the device is the same as it was when the device
2321  * suspended.
2322  *
2323  * If @udev->reset_resume is set then this routine won't check that the
2324  * port is still enabled.  Furthermore, finish_port_resume() above will
2325  * reset @udev.  The end result is that a broken power session can be
2326  * recovered and @udev will appear to persist across a loss of VBUS power.
2327  *
2328  * For example, if a host controller doesn't maintain VBUS suspend current
2329  * during a system sleep or is reset when the system wakes up, all the USB
2330  * power sessions below it will be broken.  This is especially troublesome
2331  * for mass-storage devices containing mounted filesystems, since the
2332  * device will appear to have disconnected and all the memory mappings
2333  * to it will be lost.  Using the USB_PERSIST facility, the device can be
2334  * made to appear as if it had not disconnected.
2335  *
2336  * This facility can be dangerous.  Although usb_reset_and_verify_device() makes
2337  * every effort to insure that the same device is present after the
2338  * reset as before, it cannot provide a 100% guarantee.  Furthermore it's
2339  * quite possible for a device to remain unaltered but its media to be
2340  * changed.  If the user replaces a flash memory card while the system is
2341  * asleep, he will have only himself to blame when the filesystem on the
2342  * new card is corrupted and the system crashes.
2343  *
2344  * Returns 0 on success, else negative errno.
2345  */
2346 int usb_port_resume(struct usb_device *udev, pm_message_t msg)
2347 {
2348         struct usb_hub  *hub = hdev_to_hub(udev->parent);
2349         int             port1 = udev->portnum;
2350         int             status;
2351         u16             portchange, portstatus;
2352
2353         /* Skip the initial Clear-Suspend step for a remote wakeup */
2354         status = hub_port_status(hub, port1, &portstatus, &portchange);
2355         if (status == 0 && !(portstatus & USB_PORT_STAT_SUSPEND))
2356                 goto SuspendCleared;
2357
2358         // dev_dbg(hub->intfdev, "resume port %d\n", port1);
2359
2360         set_bit(port1, hub->busy_bits);
2361
2362         /* see 7.1.7.7; affects power usage, but not budgeting */
2363         status = clear_port_feature(hub->hdev,
2364                         port1, USB_PORT_FEAT_SUSPEND);
2365         if (status) {
2366                 dev_dbg(hub->intfdev, "can't resume port %d, status %d\n",
2367                                 port1, status);
2368         } else {
2369                 /* drive resume for at least 20 msec */
2370                 dev_dbg(&udev->dev, "usb %sresume\n",
2371                                 (msg.event & PM_EVENT_AUTO ? "auto-" : ""));
2372                 msleep(25);
2373
2374                 /* Virtual root hubs can trigger on GET_PORT_STATUS to
2375                  * stop resume signaling.  Then finish the resume
2376                  * sequence.
2377                  */
2378                 status = hub_port_status(hub, port1, &portstatus, &portchange);
2379
2380                 /* TRSMRCY = 10 msec */
2381                 msleep(10);
2382         }
2383
2384  SuspendCleared:
2385         if (status == 0) {
2386                 if (portchange & USB_PORT_STAT_C_SUSPEND)
2387                         clear_port_feature(hub->hdev, port1,
2388                                         USB_PORT_FEAT_C_SUSPEND);
2389         }
2390
2391         clear_bit(port1, hub->busy_bits);
2392
2393         status = check_port_resume_type(udev,
2394                         hub, port1, status, portchange, portstatus);
2395         if (status == 0)
2396                 status = finish_port_resume(udev);
2397         if (status < 0) {
2398                 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
2399                 hub_port_logical_disconnect(hub, port1);
2400         }
2401         return status;
2402 }
2403
2404 /* caller has locked udev */
2405 int usb_remote_wakeup(struct usb_device *udev)
2406 {
2407         int     status = 0;
2408
2409         if (udev->state == USB_STATE_SUSPENDED) {
2410                 dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
2411                 usb_mark_last_busy(udev);
2412                 status = usb_external_resume_device(udev, PMSG_REMOTE_RESUME);
2413         }
2414         return status;
2415 }
2416
2417 #else   /* CONFIG_USB_SUSPEND */
2418
2419 /* When CONFIG_USB_SUSPEND isn't set, we never suspend or resume any ports. */
2420
2421 int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
2422 {
2423         return 0;
2424 }
2425
2426 /* However we may need to do a reset-resume */
2427
2428 int usb_port_resume(struct usb_device *udev, pm_message_t msg)
2429 {
2430         struct usb_hub  *hub = hdev_to_hub(udev->parent);
2431         int             port1 = udev->portnum;
2432         int             status;
2433         u16             portchange, portstatus;
2434
2435         status = hub_port_status(hub, port1, &portstatus, &portchange);
2436         status = check_port_resume_type(udev,
2437                         hub, port1, status, portchange, portstatus);
2438
2439         if (status) {
2440                 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
2441                 hub_port_logical_disconnect(hub, port1);
2442         } else if (udev->reset_resume) {
2443                 dev_dbg(&udev->dev, "reset-resume\n");
2444                 status = usb_reset_and_verify_device(udev);
2445         }
2446         return status;
2447 }
2448
2449 int usb_remote_wakeup(struct usb_device *udev)
2450 {
2451         return 0;
2452 }
2453
2454 #endif
2455
2456 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
2457 {
2458         struct usb_hub          *hub = usb_get_intfdata (intf);
2459         struct usb_device       *hdev = hub->hdev;
2460         unsigned                port1;
2461
2462         /* fail if children aren't already suspended */
2463         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
2464                 struct usb_device       *udev;
2465
2466                 udev = hdev->children [port1-1];
2467                 if (udev && udev->can_submit) {
2468                         if (!(msg.event & PM_EVENT_AUTO))
2469                                 dev_dbg(&intf->dev, "port %d nyet suspended\n",
2470                                                 port1);
2471                         return -EBUSY;
2472                 }
2473         }
2474
2475         dev_dbg(&intf->dev, "%s\n", __func__);
2476
2477         /* stop khubd and related activity */
2478         hub_quiesce(hub, HUB_SUSPEND);
2479         return 0;
2480 }
2481
2482 static int hub_resume(struct usb_interface *intf)
2483 {
2484         struct usb_hub *hub = usb_get_intfdata(intf);
2485
2486         dev_dbg(&intf->dev, "%s\n", __func__);
2487         hub_activate(hub, HUB_RESUME);
2488         return 0;
2489 }
2490
2491 static int hub_reset_resume(struct usb_interface *intf)
2492 {
2493         struct usb_hub *hub = usb_get_intfdata(intf);
2494
2495         dev_dbg(&intf->dev, "%s\n", __func__);
2496         hub_activate(hub, HUB_RESET_RESUME);
2497         return 0;
2498 }
2499
2500 /**
2501  * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
2502  * @rhdev: struct usb_device for the root hub
2503  *
2504  * The USB host controller driver calls this function when its root hub
2505  * is resumed and Vbus power has been interrupted or the controller
2506  * has been reset.  The routine marks @rhdev as having lost power.
2507  * When the hub driver is resumed it will take notice and carry out
2508  * power-session recovery for all the "USB-PERSIST"-enabled child devices;
2509  * the others will be disconnected.
2510  */
2511 void usb_root_hub_lost_power(struct usb_device *rhdev)
2512 {
2513         dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
2514         rhdev->reset_resume = 1;
2515 }
2516 EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
2517
2518 #else   /* CONFIG_PM */
2519
2520 #define hub_suspend             NULL
2521 #define hub_resume              NULL
2522 #define hub_reset_resume        NULL
2523 #endif
2524
2525
2526 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
2527  *
2528  * Between connect detection and reset signaling there must be a delay
2529  * of 100ms at least for debounce and power-settling.  The corresponding
2530  * timer shall restart whenever the downstream port detects a disconnect.
2531  * 
2532  * Apparently there are some bluetooth and irda-dongles and a number of
2533  * low-speed devices for which this debounce period may last over a second.
2534  * Not covered by the spec - but easy to deal with.
2535  *
2536  * This implementation uses a 1500ms total debounce timeout; if the
2537  * connection isn't stable by then it returns -ETIMEDOUT.  It checks
2538  * every 25ms for transient disconnects.  When the port status has been
2539  * unchanged for 100ms it returns the port status.
2540  */
2541 static int hub_port_debounce(struct usb_hub *hub, int port1)
2542 {
2543         int ret;
2544         int total_time, stable_time = 0;
2545         u16 portchange, portstatus;
2546         unsigned connection = 0xffff;
2547
2548         for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
2549                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2550                 if (ret < 0)
2551                         return ret;
2552
2553                 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
2554                      (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2555                         stable_time += HUB_DEBOUNCE_STEP;
2556                         if (stable_time >= HUB_DEBOUNCE_STABLE)
2557                                 break;
2558                 } else {
2559                         stable_time = 0;
2560                         connection = portstatus & USB_PORT_STAT_CONNECTION;
2561                 }
2562
2563                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2564                         clear_port_feature(hub->hdev, port1,
2565                                         USB_PORT_FEAT_C_CONNECTION);
2566                 }
2567
2568                 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2569                         break;
2570                 msleep(HUB_DEBOUNCE_STEP);
2571         }
2572
2573         dev_dbg (hub->intfdev,
2574                 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2575                 port1, total_time, stable_time, portstatus);
2576
2577         if (stable_time < HUB_DEBOUNCE_STABLE)
2578                 return -ETIMEDOUT;
2579         return portstatus;
2580 }
2581
2582 void usb_ep0_reinit(struct usb_device *udev)
2583 {
2584         usb_disable_endpoint(udev, 0 + USB_DIR_IN, true);
2585         usb_disable_endpoint(udev, 0 + USB_DIR_OUT, true);
2586         usb_enable_endpoint(udev, &udev->ep0, true);
2587 }
2588 EXPORT_SYMBOL_GPL(usb_ep0_reinit);
2589
2590 #define usb_sndaddr0pipe()      (PIPE_CONTROL << 30)
2591 #define usb_rcvaddr0pipe()      ((PIPE_CONTROL << 30) | USB_DIR_IN)
2592
2593 static int hub_set_address(struct usb_device *udev, int devnum)
2594 {
2595         int retval;
2596         struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2597
2598         /*
2599          * The host controller will choose the device address,
2600          * instead of the core having chosen it earlier
2601          */
2602         if (!hcd->driver->address_device && devnum <= 1)
2603                 return -EINVAL;
2604         if (udev->state == USB_STATE_ADDRESS)
2605                 return 0;
2606         if (udev->state != USB_STATE_DEFAULT)
2607                 return -EINVAL;
2608         if (hcd->driver->address_device) {
2609                 retval = hcd->driver->address_device(hcd, udev);
2610         } else {
2611                 retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2612                                 USB_REQ_SET_ADDRESS, 0, devnum, 0,
2613                                 NULL, 0, USB_CTRL_SET_TIMEOUT);
2614                 if (retval == 0)
2615                         update_address(udev, devnum);
2616         }
2617         if (retval == 0) {
2618                 /* Device now using proper address. */
2619                 usb_set_device_state(udev, USB_STATE_ADDRESS);
2620                 usb_ep0_reinit(udev);
2621         }
2622         return retval;
2623 }
2624
2625 /* Reset device, (re)assign address, get device descriptor.
2626  * Device connection must be stable, no more debouncing needed.
2627  * Returns device in USB_STATE_ADDRESS, except on error.
2628  *
2629  * If this is called for an already-existing device (as part of
2630  * usb_reset_and_verify_device), the caller must own the device lock.  For a
2631  * newly detected device that is not accessible through any global
2632  * pointers, it's not necessary to lock the device.
2633  */
2634 static int
2635 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2636                 int retry_counter)
2637 {
2638         static DEFINE_MUTEX(usb_address0_mutex);
2639
2640         struct usb_device       *hdev = hub->hdev;
2641         struct usb_hcd          *hcd = bus_to_hcd(hdev->bus);
2642         int                     i, j, retval;
2643         unsigned                delay = HUB_SHORT_RESET_TIME;
2644         enum usb_device_speed   oldspeed = udev->speed;
2645         char                    *speed, *type;
2646         int                     devnum = udev->devnum;
2647
2648         /* root hub ports have a slightly longer reset period
2649          * (from USB 2.0 spec, section 7.1.7.5)
2650          */
2651         if (!hdev->parent) {
2652                 delay = HUB_ROOT_RESET_TIME;
2653                 if (port1 == hdev->bus->otg_port)
2654                         hdev->bus->b_hnp_enable = 0;
2655         }
2656
2657         /* Some low speed devices have problems with the quick delay, so */
2658         /*  be a bit pessimistic with those devices. RHbug #23670 */
2659         if (oldspeed == USB_SPEED_LOW)
2660                 delay = HUB_LONG_RESET_TIME;
2661
2662         mutex_lock(&usb_address0_mutex);
2663
2664         if (!udev->config && oldspeed == USB_SPEED_SUPER) {
2665                 /* Don't reset USB 3.0 devices during an initial setup */
2666                 usb_set_device_state(udev, USB_STATE_DEFAULT);
2667         } else {
2668                 /* Reset the device; full speed may morph to high speed */
2669                 /* FIXME a USB 2.0 device may morph into SuperSpeed on reset. */
2670                 retval = hub_port_reset(hub, port1, udev, delay);
2671                 if (retval < 0)         /* error or disconnect */
2672                         goto fail;
2673                 /* success, speed is known */
2674         }
2675         retval = -ENODEV;
2676
2677         if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2678                 dev_dbg(&udev->dev, "device reset changed speed!\n");
2679                 goto fail;
2680         }
2681         oldspeed = udev->speed;
2682
2683         /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2684          * it's fixed size except for full speed devices.
2685          * For Wireless USB devices, ep0 max packet is always 512 (tho
2686          * reported as 0xff in the device descriptor). WUSB1.0[4.8.1].
2687          */
2688         switch (udev->speed) {
2689         case USB_SPEED_SUPER:
2690         case USB_SPEED_WIRELESS:        /* fixed at 512 */
2691                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(512);
2692                 break;
2693         case USB_SPEED_HIGH:            /* fixed at 64 */
2694                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
2695                 break;
2696         case USB_SPEED_FULL:            /* 8, 16, 32, or 64 */
2697                 /* to determine the ep0 maxpacket size, try to read
2698                  * the device descriptor to get bMaxPacketSize0 and
2699                  * then correct our initial guess.
2700                  */
2701                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
2702                 break;
2703         case USB_SPEED_LOW:             /* fixed at 8 */
2704                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(8);
2705                 break;
2706         default:
2707                 goto fail;
2708         }
2709  
2710         type = "";
2711         switch (udev->speed) {
2712         case USB_SPEED_LOW:     speed = "low";  break;
2713         case USB_SPEED_FULL:    speed = "full"; break;
2714         case USB_SPEED_HIGH:    speed = "high"; break;
2715         case USB_SPEED_SUPER:
2716                                 speed = "super";
2717                                 break;
2718         case USB_SPEED_WIRELESS:
2719                                 speed = "variable";
2720                                 type = "Wireless ";
2721                                 break;
2722         default:                speed = "?";    break;
2723         }
2724         if (udev->speed != USB_SPEED_SUPER)
2725                 dev_info(&udev->dev,
2726                                 "%s %s speed %sUSB device using %s and address %d\n",
2727                                 (udev->config) ? "reset" : "new", speed, type,
2728                                 udev->bus->controller->driver->name, devnum);
2729
2730         /* Set up TT records, if needed  */
2731         if (hdev->tt) {
2732                 udev->tt = hdev->tt;
2733                 udev->ttport = hdev->ttport;
2734         } else if (udev->speed != USB_SPEED_HIGH
2735                         && hdev->speed == USB_SPEED_HIGH) {
2736                 udev->tt = &hub->tt;
2737                 udev->ttport = port1;
2738         }
2739  
2740         /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2741          * Because device hardware and firmware is sometimes buggy in
2742          * this area, and this is how Linux has done it for ages.
2743          * Change it cautiously.
2744          *
2745          * NOTE:  If USE_NEW_SCHEME() is true we will start by issuing
2746          * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
2747          * so it may help with some non-standards-compliant devices.
2748          * Otherwise we start with SET_ADDRESS and then try to read the
2749          * first 8 bytes of the device descriptor to get the ep0 maxpacket
2750          * value.
2751          */
2752         for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2753                 /*
2754                  * An xHCI controller cannot send any packets to a device until
2755                  * a set address command successfully completes.
2756                  */
2757                 if (USE_NEW_SCHEME(retry_counter) && !(hcd->driver->flags & HCD_USB3)) {
2758                         struct usb_device_descriptor *buf;
2759                         int r = 0;
2760
2761 #define GET_DESCRIPTOR_BUFSIZE  64
2762                         buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2763                         if (!buf) {
2764                                 retval = -ENOMEM;
2765                                 continue;
2766                         }
2767
2768                         /* Retry on all errors; some devices are flakey.
2769                          * 255 is for WUSB devices, we actually need to use
2770                          * 512 (WUSB1.0[4.8.1]).
2771                          */
2772                         for (j = 0; j < 3; ++j) {
2773                                 buf->bMaxPacketSize0 = 0;
2774                                 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2775                                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2776                                         USB_DT_DEVICE << 8, 0,
2777                                         buf, GET_DESCRIPTOR_BUFSIZE,
2778                                         initial_descriptor_timeout);
2779                                 switch (buf->bMaxPacketSize0) {
2780                                 case 8: case 16: case 32: case 64: case 255:
2781                                         if (buf->bDescriptorType ==
2782                                                         USB_DT_DEVICE) {
2783                                                 r = 0;
2784                                                 break;
2785                                         }
2786                                         /* FALL THROUGH */
2787                                 default:
2788                                         if (r == 0)
2789                                                 r = -EPROTO;
2790                                         break;
2791                                 }
2792                                 if (r == 0)
2793                                         break;
2794                         }
2795                         udev->descriptor.bMaxPacketSize0 =
2796                                         buf->bMaxPacketSize0;
2797                         kfree(buf);
2798
2799                         retval = hub_port_reset(hub, port1, udev, delay);
2800                         if (retval < 0)         /* error or disconnect */
2801                                 goto fail;
2802                         if (oldspeed != udev->speed) {
2803                                 dev_dbg(&udev->dev,
2804                                         "device reset changed speed!\n");
2805                                 retval = -ENODEV;
2806                                 goto fail;
2807                         }
2808                         if (r) {
2809                                 dev_err(&udev->dev,
2810                                         "device descriptor read/64, error %d\n",
2811                                         r);
2812                                 retval = -EMSGSIZE;
2813                                 continue;
2814                         }
2815 #undef GET_DESCRIPTOR_BUFSIZE
2816                 }
2817
2818                 /*
2819                  * If device is WUSB, we already assigned an
2820                  * unauthorized address in the Connect Ack sequence;
2821                  * authorization will assign the final address.
2822                  */
2823                 if (udev->wusb == 0) {
2824                         for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2825                                 retval = hub_set_address(udev, devnum);
2826                                 if (retval >= 0)
2827                                         break;
2828                                 msleep(200);
2829                         }
2830                         if (retval < 0) {
2831                                 dev_err(&udev->dev,
2832                                         "device not accepting address %d, error %d\n",
2833                                         devnum, retval);
2834                                 goto fail;
2835                         }
2836                         if (udev->speed == USB_SPEED_SUPER) {
2837                                 devnum = udev->devnum;
2838                                 dev_info(&udev->dev,
2839                                                 "%s SuperSpeed USB device using %s and address %d\n",
2840                                                 (udev->config) ? "reset" : "new",
2841                                                 udev->bus->controller->driver->name, devnum);
2842                         }
2843
2844                         /* cope with hardware quirkiness:
2845                          *  - let SET_ADDRESS settle, some device hardware wants it
2846                          *  - read ep0 maxpacket even for high and low speed,
2847                          */
2848                         msleep(10);
2849                         if (USE_NEW_SCHEME(retry_counter) && !(hcd->driver->flags & HCD_USB3))
2850                                 break;
2851                 }
2852
2853                 retval = usb_get_device_descriptor(udev, 8);
2854                 if (retval < 8) {
2855                         dev_err(&udev->dev,
2856                                         "device descriptor read/8, error %d\n",
2857                                         retval);
2858                         if (retval >= 0)
2859                                 retval = -EMSGSIZE;
2860                 } else {
2861                         retval = 0;
2862                         break;
2863                 }
2864         }
2865         if (retval)
2866                 goto fail;
2867
2868         if (udev->descriptor.bMaxPacketSize0 == 0xff ||
2869                         udev->speed == USB_SPEED_SUPER)
2870                 i = 512;
2871         else
2872                 i = udev->descriptor.bMaxPacketSize0;
2873         if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2874                 if (udev->speed != USB_SPEED_FULL ||
2875                                 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2876                         dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
2877                         retval = -EMSGSIZE;
2878                         goto fail;
2879                 }
2880                 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2881                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2882                 usb_ep0_reinit(udev);
2883         }
2884   
2885         retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2886         if (retval < (signed)sizeof(udev->descriptor)) {
2887                 dev_err(&udev->dev, "device descriptor read/all, error %d\n",
2888                         retval);
2889                 if (retval >= 0)
2890                         retval = -ENOMSG;
2891                 goto fail;
2892         }
2893
2894         retval = 0;
2895
2896 fail:
2897         if (retval) {
2898                 hub_port_disable(hub, port1, 0);
2899                 update_address(udev, devnum);   /* for disconnect processing */
2900         }
2901         mutex_unlock(&usb_address0_mutex);
2902         return retval;
2903 }
2904
2905 static void
2906 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2907 {
2908         struct usb_qualifier_descriptor *qual;
2909         int                             status;
2910
2911         qual = kmalloc (sizeof *qual, GFP_KERNEL);
2912         if (qual == NULL)
2913                 return;
2914
2915         status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2916                         qual, sizeof *qual);
2917         if (status == sizeof *qual) {
2918                 dev_info(&udev->dev, "not running at top speed; "
2919                         "connect to a high speed hub\n");
2920                 /* hub LEDs are probably harder to miss than syslog */
2921                 if (hub->has_indicators) {
2922                         hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2923                         schedule_delayed_work (&hub->leds, 0);
2924                 }
2925         }
2926         kfree(qual);
2927 }
2928
2929 static unsigned
2930 hub_power_remaining (struct usb_hub *hub)
2931 {
2932         struct usb_device *hdev = hub->hdev;
2933         int remaining;
2934         int port1;
2935
2936         if (!hub->limited_power)
2937                 return 0;
2938
2939         remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
2940         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
2941                 struct usb_device       *udev = hdev->children[port1 - 1];
2942                 int                     delta;
2943
2944                 if (!udev)
2945                         continue;
2946
2947                 /* Unconfigured devices may not use more than 100mA,
2948                  * or 8mA for OTG ports */
2949                 if (udev->actconfig)
2950                         delta = udev->actconfig->desc.bMaxPower * 2;
2951                 else if (port1 != udev->bus->otg_port || hdev->parent)
2952                         delta = 100;
2953                 else
2954                         delta = 8;
2955                 if (delta > hub->mA_per_port)
2956                         dev_warn(&udev->dev,
2957                                  "%dmA is over %umA budget for port %d!\n",
2958                                  delta, hub->mA_per_port, port1);
2959                 remaining -= delta;
2960         }
2961         if (remaining < 0) {
2962                 dev_warn(hub->intfdev, "%dmA over power budget!\n",
2963                         - remaining);
2964                 remaining = 0;
2965         }
2966         return remaining;
2967 }
2968
2969 /* Handle physical or logical connection change events.
2970  * This routine is called when:
2971  *      a port connection-change occurs;
2972  *      a port enable-change occurs (often caused by EMI);
2973  *      usb_reset_and_verify_device() encounters changed descriptors (as from
2974  *              a firmware download)
2975  * caller already locked the hub
2976  */
2977 static void hub_port_connect_change(struct usb_hub *hub, int port1,
2978                                         u16 portstatus, u16 portchange)
2979 {
2980         struct usb_device *hdev = hub->hdev;
2981         struct device *hub_dev = hub->intfdev;
2982         struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
2983         unsigned wHubCharacteristics =
2984                         le16_to_cpu(hub->descriptor->wHubCharacteristics);
2985         struct usb_device *udev;
2986         int status, i;
2987
2988         dev_dbg (hub_dev,
2989                 "port %d, status %04x, change %04x, %s\n",
2990                 port1, portstatus, portchange, portspeed (portstatus));
2991
2992         if (hub->has_indicators) {
2993                 set_port_led(hub, port1, HUB_LED_AUTO);
2994                 hub->indicator[port1-1] = INDICATOR_AUTO;
2995         }
2996
2997 #ifdef  CONFIG_USB_OTG
2998         /* during HNP, don't repeat the debounce */
2999         if (hdev->bus->is_b_host)
3000                 portchange &= ~(USB_PORT_STAT_C_CONNECTION |
3001                                 USB_PORT_STAT_C_ENABLE);
3002 #endif
3003
3004         /* Try to resuscitate an existing device */
3005         udev = hdev->children[port1-1];
3006         if ((portstatus & USB_PORT_STAT_CONNECTION) && udev &&
3007                         udev->state != USB_STATE_NOTATTACHED) {
3008                 usb_lock_device(udev);
3009                 if (portstatus & USB_PORT_STAT_ENABLE) {
3010                         status = 0;             /* Nothing to do */
3011
3012 #ifdef CONFIG_USB_SUSPEND
3013                 } else if (udev->state == USB_STATE_SUSPENDED &&
3014                                 udev->persist_enabled) {
3015                         /* For a suspended device, treat this as a
3016                          * remote wakeup event.
3017                          */
3018                         status = usb_remote_wakeup(udev);
3019 #endif
3020
3021                 } else {
3022                         status = -ENODEV;       /* Don't resuscitate */
3023                 }
3024                 usb_unlock_device(udev);
3025
3026                 if (status == 0) {
3027                         clear_bit(port1, hub->change_bits);
3028                         return;
3029                 }
3030         }
3031
3032         /* Disconnect any existing devices under this port */
3033         if (udev)
3034                 usb_disconnect(&hdev->children[port1-1]);
3035         clear_bit(port1, hub->change_bits);
3036
3037         /* We can forget about a "removed" device when there's a physical
3038          * disconnect or the connect status changes.
3039          */
3040         if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
3041                         (portchange & USB_PORT_STAT_C_CONNECTION))
3042                 clear_bit(port1, hub->removed_bits);
3043
3044         if (portchange & (USB_PORT_STAT_C_CONNECTION |
3045                                 USB_PORT_STAT_C_ENABLE)) {
3046                 status = hub_port_debounce(hub, port1);
3047                 if (status < 0) {
3048                         if (printk_ratelimit())
3049                                 dev_err(hub_dev, "connect-debounce failed, "
3050                                                 "port %d disabled\n", port1);
3051                         portstatus &= ~USB_PORT_STAT_CONNECTION;
3052                 } else {
3053                         portstatus = status;
3054                 }
3055         }
3056
3057         /* Return now if debouncing failed or nothing is connected or
3058          * the device was "removed".
3059          */
3060         if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
3061                         test_bit(port1, hub->removed_bits)) {
3062
3063                 /* maybe switch power back on (e.g. root hub was reset) */
3064                 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2
3065                                 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
3066                         set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
3067
3068                 if (portstatus & USB_PORT_STAT_ENABLE)
3069                         goto done;
3070                 return;
3071         }
3072
3073         for (i = 0; i < SET_CONFIG_TRIES; i++) {
3074
3075                 /* reallocate for each attempt, since references
3076                  * to the previous one can escape in various ways
3077                  */
3078                 udev = usb_alloc_dev(hdev, hdev->bus, port1);
3079                 if (!udev) {
3080                         dev_err (hub_dev,
3081                                 "couldn't allocate port %d usb_device\n",
3082                                 port1);
3083                         goto done;
3084                 }
3085
3086                 usb_set_device_state(udev, USB_STATE_POWERED);
3087                 udev->bus_mA = hub->mA_per_port;
3088                 udev->level = hdev->level + 1;
3089                 udev->wusb = hub_is_wusb(hub);
3090
3091                 /*
3092                  * USB 3.0 devices are reset automatically before the connect
3093                  * port status change appears, and the root hub port status
3094                  * shows the correct speed.  We also get port change
3095                  * notifications for USB 3.0 devices from the USB 3.0 portion of
3096                  * an external USB 3.0 hub, but this isn't handled correctly yet
3097                  * FIXME.
3098                  */
3099
3100                 if (!(hcd->driver->flags & HCD_USB3))
3101                         udev->speed = USB_SPEED_UNKNOWN;
3102                 else if ((hdev->parent == NULL) &&
3103                                 (portstatus & (1 << USB_PORT_FEAT_SUPERSPEED)))
3104                         udev->speed = USB_SPEED_SUPER;
3105                 else
3106                         udev->speed = USB_SPEED_UNKNOWN;
3107
3108                 /*
3109                  * xHCI needs to issue an address device command later
3110                  * in the hub_port_init sequence for SS/HS/FS/LS devices.
3111                  */
3112                 if (!(hcd->driver->flags & HCD_USB3)) {
3113                         /* set the address */
3114                         choose_address(udev);
3115                         if (udev->devnum <= 0) {
3116                                 status = -ENOTCONN;     /* Don't retry */
3117                                 goto loop;
3118                         }
3119                 }
3120
3121                 /* reset (non-USB 3.0 devices) and get descriptor */
3122                 status = hub_port_init(hub, udev, port1, i);
3123                 if (status < 0)
3124                         goto loop;
3125
3126                 /* consecutive bus-powered hubs aren't reliable; they can
3127                  * violate the voltage drop budget.  if the new child has
3128                  * a "powered" LED, users should notice we didn't enable it
3129                  * (without reading syslog), even without per-port LEDs
3130                  * on the parent.
3131                  */
3132                 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
3133                                 && udev->bus_mA <= 100) {
3134                         u16     devstat;
3135
3136                         status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
3137                                         &devstat);
3138                         if (status < 2) {
3139                                 dev_dbg(&udev->dev, "get status %d ?\n", status);
3140                                 goto loop_disable;
3141                         }
3142                         le16_to_cpus(&devstat);
3143                         if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
3144                                 dev_err(&udev->dev,
3145                                         "can't connect bus-powered hub "
3146                                         "to this port\n");
3147                                 if (hub->has_indicators) {
3148                                         hub->indicator[port1-1] =
3149                                                 INDICATOR_AMBER_BLINK;
3150                                         schedule_delayed_work (&hub->leds, 0);
3151                                 }
3152                                 status = -ENOTCONN;     /* Don't retry */
3153                                 goto loop_disable;
3154                         }
3155                 }
3156  
3157                 /* check for devices running slower than they could */
3158                 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
3159                                 && udev->speed == USB_SPEED_FULL
3160                                 && highspeed_hubs != 0)
3161                         check_highspeed (hub, udev, port1);
3162
3163                 /* Store the parent's children[] pointer.  At this point
3164                  * udev becomes globally accessible, although presumably
3165                  * no one will look at it until hdev is unlocked.
3166                  */
3167                 status = 0;
3168
3169                 /* We mustn't add new devices if the parent hub has
3170                  * been disconnected; we would race with the
3171                  * recursively_mark_NOTATTACHED() routine.
3172                  */
3173                 spin_lock_irq(&device_state_lock);
3174                 if (hdev->state == USB_STATE_NOTATTACHED)
3175                         status = -ENOTCONN;
3176                 else
3177                         hdev->children[port1-1] = udev;
3178                 spin_unlock_irq(&device_state_lock);
3179
3180                 /* Run it through the hoops (find a driver, etc) */
3181                 if (!status) {
3182                         status = usb_new_device(udev);
3183                         if (status) {
3184                                 spin_lock_irq(&device_state_lock);
3185                                 hdev->children[port1-1] = NULL;
3186                                 spin_unlock_irq(&device_state_lock);
3187                         }
3188                 }
3189
3190                 if (status)
3191                         goto loop_disable;
3192
3193                 status = hub_power_remaining(hub);
3194                 if (status)
3195                         dev_dbg(hub_dev, "%dmA power budget left\n", status);
3196
3197                 return;
3198
3199 loop_disable:
3200                 hub_port_disable(hub, port1, 1);
3201 loop:
3202                 usb_ep0_reinit(udev);
3203                 release_address(udev);
3204                 usb_put_dev(udev);
3205                 if ((status == -ENOTCONN) || (status == -ENOTSUPP))
3206                         break;
3207         }
3208         if (hub->hdev->parent ||
3209                         !hcd->driver->port_handed_over ||
3210                         !(hcd->driver->port_handed_over)(hcd, port1))
3211                 dev_err(hub_dev, "unable to enumerate USB device on port %d\n",
3212                                 port1);
3213  
3214 done:
3215         hub_port_disable(hub, port1, 1);
3216         if (hcd->driver->relinquish_port && !hub->hdev->parent)
3217                 hcd->driver->relinquish_port(hcd, port1);
3218 }
3219
3220 static void hub_events(void)
3221 {
3222         struct list_head *tmp;
3223         struct usb_device *hdev;
3224         struct usb_interface *intf;
3225         struct usb_hub *hub;
3226         struct device *hub_dev;
3227         u16 hubstatus;
3228         u16 hubchange;
3229         u16 portstatus;
3230         u16 portchange;
3231         int i, ret;
3232         int connect_change;
3233
3234         /*
3235          *  We restart the list every time to avoid a deadlock with
3236          * deleting hubs downstream from this one. This should be
3237          * safe since we delete the hub from the event list.
3238          * Not the most efficient, but avoids deadlocks.
3239          */
3240         while (1) {
3241
3242                 /* Grab the first entry at the beginning of the list */
3243                 spin_lock_irq(&hub_event_lock);
3244                 if (list_empty(&hub_event_list)) {
3245                         spin_unlock_irq(&hub_event_lock);
3246                         break;
3247                 }
3248
3249                 tmp = hub_event_list.next;
3250                 list_del_init(tmp);
3251
3252                 hub = list_entry(tmp, struct usb_hub, event_list);
3253                 kref_get(&hub->kref);
3254                 spin_unlock_irq(&hub_event_lock);
3255
3256                 hdev = hub->hdev;
3257                 hub_dev = hub->intfdev;
3258                 intf = to_usb_interface(hub_dev);
3259                 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
3260                                 hdev->state, hub->descriptor
3261                                         ? hub->descriptor->bNbrPorts
3262                                         : 0,
3263                                 /* NOTE: expects max 15 ports... */
3264                                 (u16) hub->change_bits[0],
3265                                 (u16) hub->event_bits[0]);
3266
3267                 /* Lock the device, then check to see if we were
3268                  * disconnected while waiting for the lock to succeed. */
3269                 usb_lock_device(hdev);
3270                 if (unlikely(hub->disconnected))
3271                         goto loop2;
3272
3273                 /* If the hub has died, clean up after it */
3274                 if (hdev->state == USB_STATE_NOTATTACHED) {
3275                         hub->error = -ENODEV;
3276                         hub_quiesce(hub, HUB_DISCONNECT);
3277                         goto loop;
3278                 }
3279
3280                 /* Autoresume */
3281                 ret = usb_autopm_get_interface(intf);
3282                 if (ret) {
3283                         dev_dbg(hub_dev, "Can't autoresume: %d\n", ret);
3284                         goto loop;
3285                 }
3286
3287                 /* If this is an inactive hub, do nothing */
3288                 if (hub->quiescing)
3289                         goto loop_autopm;
3290
3291                 if (hub->error) {
3292                         dev_dbg (hub_dev, "resetting for error %d\n",
3293                                 hub->error);
3294
3295                         ret = usb_reset_device(hdev);
3296                         if (ret) {
3297                                 dev_dbg (hub_dev,
3298                                         "error resetting hub: %d\n", ret);
3299                                 goto loop_autopm;
3300                         }
3301
3302                         hub->nerrors = 0;
3303                         hub->error = 0;
3304                 }
3305
3306                 /* deal with port status changes */
3307                 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
3308                         if (test_bit(i, hub->busy_bits))
3309                                 continue;
3310                         connect_change = test_bit(i, hub->change_bits);
3311                         if (!test_and_clear_bit(i, hub->event_bits) &&
3312                                         !connect_change)
3313                                 continue;
3314
3315                         ret = hub_port_status(hub, i,
3316                                         &portstatus, &portchange);
3317                         if (ret < 0)
3318                                 continue;
3319
3320                         if (portchange & USB_PORT_STAT_C_CONNECTION) {
3321                                 clear_port_feature(hdev, i,
3322                                         USB_PORT_FEAT_C_CONNECTION);
3323                                 connect_change = 1;
3324                         }
3325
3326                         if (portchange & USB_PORT_STAT_C_ENABLE) {
3327                                 if (!connect_change)
3328                                         dev_dbg (hub_dev,
3329                                                 "port %d enable change, "
3330                                                 "status %08x\n",
3331                                                 i, portstatus);
3332                                 clear_port_feature(hdev, i,
3333                                         USB_PORT_FEAT_C_ENABLE);
3334
3335                                 /*
3336                                  * EM interference sometimes causes badly
3337                                  * shielded USB devices to be shutdown by
3338                                  * the hub, this hack enables them again.
3339                                  * Works at least with mouse driver. 
3340                                  */
3341                                 if (!(portstatus & USB_PORT_STAT_ENABLE)
3342                                     && !connect_change
3343                                     && hdev->children[i-1]) {
3344                                         dev_err (hub_dev,
3345                                             "port %i "
3346                                             "disabled by hub (EMI?), "
3347                                             "re-enabling...\n",
3348                                                 i);
3349                                         connect_change = 1;
3350                                 }
3351                         }
3352
3353                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
3354                                 struct usb_device *udev;
3355
3356                                 clear_port_feature(hdev, i,
3357                                         USB_PORT_FEAT_C_SUSPEND);
3358                                 udev = hdev->children[i-1];
3359                                 if (udev) {
3360                                         /* TRSMRCY = 10 msec */
3361                                         msleep(10);
3362
3363                                         usb_lock_device(udev);
3364                                         ret = usb_remote_wakeup(hdev->
3365                                                         children[i-1]);
3366                                         usb_unlock_device(udev);
3367                                         if (ret < 0)
3368                                                 connect_change = 1;
3369                                 } else {
3370                                         ret = -ENODEV;
3371                                         hub_port_disable(hub, i, 1);
3372                                 }
3373                                 dev_dbg (hub_dev,
3374                                         "resume on port %d, status %d\n",
3375                                         i, ret);
3376                         }
3377                         
3378                         if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
3379                                 dev_err (hub_dev,
3380                                         "over-current change on port %d\n",
3381                                         i);
3382                                 clear_port_feature(hdev, i,
3383                                         USB_PORT_FEAT_C_OVER_CURRENT);
3384                                 hub_power_on(hub, true);
3385                         }
3386
3387                         if (portchange & USB_PORT_STAT_C_RESET) {
3388                                 dev_dbg (hub_dev,
3389                                         "reset change on port %d\n",
3390                                         i);
3391                                 clear_port_feature(hdev, i,
3392                                         USB_PORT_FEAT_C_RESET);
3393                         }
3394
3395                         if (connect_change)
3396                                 hub_port_connect_change(hub, i,
3397                                                 portstatus, portchange);
3398                 } /* end for i */
3399
3400                 /* deal with hub status changes */
3401                 if (test_and_clear_bit(0, hub->event_bits) == 0)
3402                         ;       /* do nothing */
3403                 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
3404                         dev_err (hub_dev, "get_hub_status failed\n");
3405                 else {
3406                         if (hubchange & HUB_CHANGE_LOCAL_POWER) {
3407                                 dev_dbg (hub_dev, "power change\n");
3408                                 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
3409                                 if (hubstatus & HUB_STATUS_LOCAL_POWER)
3410                                         /* FIXME: Is this always true? */
3411                                         hub->limited_power = 1;
3412                                 else
3413                                         hub->limited_power = 0;
3414                         }
3415                         if (hubchange & HUB_CHANGE_OVERCURRENT) {
3416                                 dev_dbg (hub_dev, "overcurrent change\n");
3417                                 msleep(500);    /* Cool down */
3418                                 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
3419                                 hub_power_on(hub, true);
3420                         }
3421                 }
3422
3423  loop_autopm:
3424                 /* Balance the usb_autopm_get_interface() above */
3425                 usb_autopm_put_interface_no_suspend(intf);
3426  loop:
3427                 /* Balance the usb_autopm_get_interface_no_resume() in
3428                  * kick_khubd() and allow autosuspend.
3429                  */
3430                 usb_autopm_put_interface(intf);
3431  loop2:
3432                 usb_unlock_device(hdev);
3433                 kref_put(&hub->kref, hub_release);
3434
3435         } /* end while (1) */
3436 }
3437
3438 static int hub_thread(void *__unused)
3439 {
3440         /* khubd needs to be freezable to avoid intefering with USB-PERSIST
3441          * port handover.  Otherwise it might see that a full-speed device
3442          * was gone before the EHCI controller had handed its port over to
3443          * the companion full-speed controller.
3444          */
3445         set_freezable();
3446
3447         do {
3448                 hub_events();
3449                 wait_event_freezable(khubd_wait,
3450                                 !list_empty(&hub_event_list) ||
3451                                 kthread_should_stop());
3452         } while (!kthread_should_stop() || !list_empty(&hub_event_list));
3453
3454         pr_debug("%s: khubd exiting\n", usbcore_name);
3455         return 0;
3456 }
3457
3458 static struct usb_device_id hub_id_table [] = {
3459     { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
3460       .bDeviceClass = USB_CLASS_HUB},
3461     { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
3462       .bInterfaceClass = USB_CLASS_HUB},
3463     { }                                         /* Terminating entry */
3464 };
3465
3466 MODULE_DEVICE_TABLE (usb, hub_id_table);
3467
3468 static struct usb_driver hub_driver = {
3469         .name =         "hub",
3470         .probe =        hub_probe,
3471         .disconnect =   hub_disconnect,
3472         .suspend =      hub_suspend,
3473         .resume =       hub_resume,
3474         .reset_resume = hub_reset_resume,
3475         .pre_reset =    hub_pre_reset,
3476         .post_reset =   hub_post_reset,
3477         .ioctl =        hub_ioctl,
3478         .id_table =     hub_id_table,
3479         .supports_autosuspend = 1,
3480 };
3481
3482 int usb_hub_init(void)
3483 {
3484         if (usb_register(&hub_driver) < 0) {
3485                 printk(KERN_ERR "%s: can't register hub driver\n",
3486                         usbcore_name);
3487                 return -1;
3488         }
3489
3490         khubd_task = kthread_run(hub_thread, NULL, "khubd");
3491         if (!IS_ERR(khubd_task))
3492                 return 0;
3493
3494         /* Fall through if kernel_thread failed */
3495         usb_deregister(&hub_driver);
3496         printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
3497
3498         return -1;
3499 }
3500
3501 void usb_hub_cleanup(void)
3502 {
3503         kthread_stop(khubd_task);
3504
3505         /*
3506          * Hub resources are freed for us by usb_deregister. It calls
3507          * usb_driver_purge on every device which in turn calls that
3508          * devices disconnect function if it is using this driver.
3509          * The hub_disconnect function takes care of releasing the
3510          * individual hub resources. -greg
3511          */
3512         usb_deregister(&hub_driver);
3513 } /* usb_hub_cleanup() */
3514
3515 static int descriptors_changed(struct usb_device *udev,
3516                 struct usb_device_descriptor *old_device_descriptor)
3517 {
3518         int             changed = 0;
3519         unsigned        index;
3520         unsigned        serial_len = 0;
3521         unsigned        len;
3522         unsigned        old_length;
3523         int             length;
3524         char            *buf;
3525
3526         if (memcmp(&udev->descriptor, old_device_descriptor,
3527                         sizeof(*old_device_descriptor)) != 0)
3528                 return 1;
3529
3530         /* Since the idVendor, idProduct, and bcdDevice values in the
3531          * device descriptor haven't changed, we will assume the
3532          * Manufacturer and Product strings haven't changed either.
3533          * But the SerialNumber string could be different (e.g., a
3534          * different flash card of the same brand).
3535          */
3536         if (udev->serial)
3537                 serial_len = strlen(udev->serial) + 1;
3538
3539         len = serial_len;
3540         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
3541                 old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
3542                 len = max(len, old_length);
3543         }
3544
3545         buf = kmalloc(len, GFP_NOIO);
3546         if (buf == NULL) {
3547                 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
3548                 /* assume the worst */
3549                 return 1;
3550         }
3551         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
3552                 old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
3553                 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
3554                                 old_length);
3555                 if (length != old_length) {
3556                         dev_dbg(&udev->dev, "config index %d, error %d\n",
3557                                         index, length);
3558                         changed = 1;
3559                         break;
3560                 }
3561                 if (memcmp (buf, udev->rawdescriptors[index], old_length)
3562                                 != 0) {
3563                         dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
3564                                 index,
3565                                 ((struct usb_config_descriptor *) buf)->
3566                                         bConfigurationValue);
3567                         changed = 1;
3568                         break;
3569                 }
3570         }
3571
3572         if (!changed && serial_len) {
3573                 length = usb_string(udev, udev->descriptor.iSerialNumber,
3574                                 buf, serial_len);
3575                 if (length + 1 != serial_len) {
3576                         dev_dbg(&udev->dev, "serial string error %d\n",
3577                                         length);
3578                         changed = 1;
3579                 } else if (memcmp(buf, udev->serial, length) != 0) {
3580                         dev_dbg(&udev->dev, "serial string changed\n");
3581                         changed = 1;
3582                 }
3583         }
3584
3585         kfree(buf);
3586         return changed;
3587 }
3588
3589 /**
3590  * usb_reset_and_verify_device - perform a USB port reset to reinitialize a device
3591  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
3592  *
3593  * WARNING - don't use this routine to reset a composite device
3594  * (one with multiple interfaces owned by separate drivers)!
3595  * Use usb_reset_device() instead.
3596  *
3597  * Do a port reset, reassign the device's address, and establish its
3598  * former operating configuration.  If the reset fails, or the device's
3599  * descriptors change from their values before the reset, or the original
3600  * configuration and altsettings cannot be restored, a flag will be set
3601  * telling khubd to pretend the device has been disconnected and then
3602  * re-connected.  All drivers will be unbound, and the device will be
3603  * re-enumerated and probed all over again.
3604  *
3605  * Returns 0 if the reset succeeded, -ENODEV if the device has been
3606  * flagged for logical disconnection, or some other negative error code
3607  * if the reset wasn't even attempted.
3608  *
3609  * The caller must own the device lock.  For example, it's safe to use
3610  * this from a driver probe() routine after downloading new firmware.
3611  * For calls that might not occur during probe(), drivers should lock
3612  * the device using usb_lock_device_for_reset().
3613  *
3614  * Locking exception: This routine may also be called from within an
3615  * autoresume handler.  Such usage won't conflict with other tasks
3616  * holding the device lock because these tasks should always call
3617  * usb_autopm_resume_device(), thereby preventing any unwanted autoresume.
3618  */
3619 static int usb_reset_and_verify_device(struct usb_device *udev)
3620 {
3621         struct usb_device               *parent_hdev = udev->parent;
3622         struct usb_hub                  *parent_hub;
3623         struct usb_hcd                  *hcd = bus_to_hcd(udev->bus);
3624         struct usb_device_descriptor    descriptor = udev->descriptor;
3625         int                             i, ret = 0;
3626         int                             port1 = udev->portnum;
3627
3628         if (udev->state == USB_STATE_NOTATTACHED ||
3629                         udev->state == USB_STATE_SUSPENDED) {
3630                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
3631                                 udev->state);
3632                 return -EINVAL;
3633         }
3634
3635         if (!parent_hdev) {
3636                 /* this requires hcd-specific logic; see OHCI hc_restart() */
3637                 dev_dbg(&udev->dev, "%s for root hub!\n", __func__);
3638                 return -EISDIR;
3639         }
3640         parent_hub = hdev_to_hub(parent_hdev);
3641
3642         set_bit(port1, parent_hub->busy_bits);
3643         for (i = 0; i < SET_CONFIG_TRIES; ++i) {
3644
3645                 /* ep0 maxpacket size may change; let the HCD know about it.
3646                  * Other endpoints will be handled by re-enumeration. */
3647                 usb_ep0_reinit(udev);
3648                 ret = hub_port_init(parent_hub, udev, port1, i);
3649                 if (ret >= 0 || ret == -ENOTCONN || ret == -ENODEV)
3650                         break;
3651         }
3652         clear_bit(port1, parent_hub->busy_bits);
3653
3654         if (ret < 0)
3655                 goto re_enumerate;
3656  
3657         /* Device might have changed firmware (DFU or similar) */
3658         if (descriptors_changed(udev, &descriptor)) {
3659                 dev_info(&udev->dev, "device firmware changed\n");
3660                 udev->descriptor = descriptor;  /* for disconnect() calls */
3661                 goto re_enumerate;
3662         }
3663
3664         /* Restore the device's previous configuration */
3665         if (!udev->actconfig)
3666                 goto done;
3667
3668         mutex_lock(&hcd->bandwidth_mutex);
3669         ret = usb_hcd_alloc_bandwidth(udev, udev->actconfig, NULL, NULL);
3670         if (ret < 0) {
3671                 dev_warn(&udev->dev,
3672                                 "Busted HC?  Not enough HCD resources for "
3673                                 "old configuration.\n");
3674                 mutex_unlock(&hcd->bandwidth_mutex);
3675                 goto re_enumerate;
3676         }
3677         ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3678                         USB_REQ_SET_CONFIGURATION, 0,
3679                         udev->actconfig->desc.bConfigurationValue, 0,
3680                         NULL, 0, USB_CTRL_SET_TIMEOUT);
3681         if (ret < 0) {
3682                 dev_err(&udev->dev,
3683                         "can't restore configuration #%d (error=%d)\n",
3684                         udev->actconfig->desc.bConfigurationValue, ret);
3685                 mutex_unlock(&hcd->bandwidth_mutex);
3686                 goto re_enumerate;
3687         }
3688         mutex_unlock(&hcd->bandwidth_mutex);
3689         usb_set_device_state(udev, USB_STATE_CONFIGURED);
3690
3691         /* Put interfaces back into the same altsettings as before.
3692          * Don't bother to send the Set-Interface request for interfaces
3693          * that were already in altsetting 0; besides being unnecessary,
3694          * many devices can't handle it.  Instead just reset the host-side
3695          * endpoint state.
3696          */
3697         for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
3698                 struct usb_host_config *config = udev->actconfig;
3699                 struct usb_interface *intf = config->interface[i];
3700                 struct usb_interface_descriptor *desc;
3701
3702                 desc = &intf->cur_altsetting->desc;
3703                 if (desc->bAlternateSetting == 0) {
3704                         usb_disable_interface(udev, intf, true);
3705                         usb_enable_interface(udev, intf, true);
3706                         ret = 0;
3707                 } else {
3708                         /* Let the bandwidth allocation function know that this
3709                          * device has been reset, and it will have to use
3710                          * alternate setting 0 as the current alternate setting.
3711                          */
3712                         intf->resetting_device = 1;
3713                         ret = usb_set_interface(udev, desc->bInterfaceNumber,
3714                                         desc->bAlternateSetting);
3715                         intf->resetting_device = 0;
3716                 }
3717                 if (ret < 0) {
3718                         dev_err(&udev->dev, "failed to restore interface %d "
3719                                 "altsetting %d (error=%d)\n",
3720                                 desc->bInterfaceNumber,
3721                                 desc->bAlternateSetting,
3722                                 ret);
3723                         goto re_enumerate;
3724                 }
3725         }
3726
3727 done:
3728         return 0;
3729  
3730 re_enumerate:
3731         hub_port_logical_disconnect(parent_hub, port1);
3732         return -ENODEV;
3733 }
3734
3735 /**
3736  * usb_reset_device - warn interface drivers and perform a USB port reset
3737  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
3738  *
3739  * Warns all drivers bound to registered interfaces (using their pre_reset
3740  * method), performs the port reset, and then lets the drivers know that
3741  * the reset is over (using their post_reset method).
3742  *
3743  * Return value is the same as for usb_reset_and_verify_device().
3744  *
3745  * The caller must own the device lock.  For example, it's safe to use
3746  * this from a driver probe() routine after downloading new firmware.
3747  * For calls that might not occur during probe(), drivers should lock
3748  * the device using usb_lock_device_for_reset().
3749  *
3750  * If an interface is currently being probed or disconnected, we assume
3751  * its driver knows how to handle resets.  For all other interfaces,
3752  * if the driver doesn't have pre_reset and post_reset methods then
3753  * we attempt to unbind it and rebind afterward.
3754  */
3755 int usb_reset_device(struct usb_device *udev)
3756 {
3757         int ret;
3758         int i;
3759         struct usb_host_config *config = udev->actconfig;
3760
3761         if (udev->state == USB_STATE_NOTATTACHED ||
3762                         udev->state == USB_STATE_SUSPENDED) {
3763                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
3764                                 udev->state);
3765                 return -EINVAL;
3766         }
3767
3768         /* Prevent autosuspend during the reset */
3769         usb_autoresume_device(udev);
3770
3771         if (config) {
3772                 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
3773                         struct usb_interface *cintf = config->interface[i];
3774                         struct usb_driver *drv;
3775                         int unbind = 0;
3776
3777                         if (cintf->dev.driver) {
3778                                 drv = to_usb_driver(cintf->dev.driver);
3779                                 if (drv->pre_reset && drv->post_reset)
3780                                         unbind = (drv->pre_reset)(cintf);
3781                                 else if (cintf->condition ==
3782                                                 USB_INTERFACE_BOUND)
3783                                         unbind = 1;
3784                                 if (unbind)
3785                                         usb_forced_unbind_intf(cintf);
3786                         }
3787                 }
3788         }
3789
3790         ret = usb_reset_and_verify_device(udev);
3791
3792         if (config) {
3793                 for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
3794                         struct usb_interface *cintf = config->interface[i];
3795                         struct usb_driver *drv;
3796                         int rebind = cintf->needs_binding;
3797
3798                         if (!rebind && cintf->dev.driver) {
3799                                 drv = to_usb_driver(cintf->dev.driver);
3800                                 if (drv->post_reset)
3801                                         rebind = (drv->post_reset)(cintf);
3802                                 else if (cintf->condition ==
3803                                                 USB_INTERFACE_BOUND)
3804                                         rebind = 1;
3805                         }
3806                         if (ret == 0 && rebind)
3807                                 usb_rebind_intf(cintf);
3808                 }
3809         }
3810
3811         usb_autosuspend_device(udev);
3812         return ret;
3813 }
3814 EXPORT_SYMBOL_GPL(usb_reset_device);
3815
3816
3817 /**
3818  * usb_queue_reset_device - Reset a USB device from an atomic context
3819  * @iface: USB interface belonging to the device to reset
3820  *
3821  * This function can be used to reset a USB device from an atomic
3822  * context, where usb_reset_device() won't work (as it blocks).
3823  *
3824  * Doing a reset via this method is functionally equivalent to calling
3825  * usb_reset_device(), except for the fact that it is delayed to a
3826  * workqueue. This means that any drivers bound to other interfaces
3827  * might be unbound, as well as users from usbfs in user space.
3828  *
3829  * Corner cases:
3830  *
3831  * - Scheduling two resets at the same time from two different drivers
3832  *   attached to two different interfaces of the same device is
3833  *   possible; depending on how the driver attached to each interface
3834  *   handles ->pre_reset(), the second reset might happen or not.
3835  *
3836  * - If a driver is unbound and it had a pending reset, the reset will
3837  *   be cancelled.
3838  *
3839  * - This function can be called during .probe() or .disconnect()
3840  *   times. On return from .disconnect(), any pending resets will be
3841  *   cancelled.
3842  *
3843  * There is no no need to lock/unlock the @reset_ws as schedule_work()
3844  * does its own.
3845  *
3846  * NOTE: We don't do any reference count tracking because it is not
3847  *     needed. The lifecycle of the work_struct is tied to the
3848  *     usb_interface. Before destroying the interface we cancel the
3849  *     work_struct, so the fact that work_struct is queued and or
3850  *     running means the interface (and thus, the device) exist and
3851  *     are referenced.
3852  */
3853 void usb_queue_reset_device(struct usb_interface *iface)
3854 {
3855         schedule_work(&iface->reset_ws);
3856 }
3857 EXPORT_SYMBOL_GPL(usb_queue_reset_device);