Merge branch 'linus'
[linux-2.6] / 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/smp_lock.h>
20 #include <linux/ioctl.h>
21 #include <linux/usb.h>
22 #include <linux/usbdevice_fs.h>
23 #include <linux/kthread.h>
24 #include <linux/mutex.h>
25 #include <linux/freezer.h>
26
27 #include <asm/semaphore.h>
28 #include <asm/uaccess.h>
29 #include <asm/byteorder.h>
30
31 #include "usb.h"
32 #include "hcd.h"
33 #include "hub.h"
34
35 struct usb_hub {
36         struct device           *intfdev;       /* the "interface" device */
37         struct usb_device       *hdev;
38         struct urb              *urb;           /* for interrupt polling pipe */
39
40         /* buffer for urb ... with extra space in case of babble */
41         char                    (*buffer)[8];
42         dma_addr_t              buffer_dma;     /* DMA address for buffer */
43         union {
44                 struct usb_hub_status   hub;
45                 struct usb_port_status  port;
46         }                       *status;        /* buffer for status reports */
47
48         int                     error;          /* last reported error */
49         int                     nerrors;        /* track consecutive errors */
50
51         struct list_head        event_list;     /* hubs w/data or errs ready */
52         unsigned long           event_bits[1];  /* status change bitmask */
53         unsigned long           change_bits[1]; /* ports with logical connect
54                                                         status change */
55         unsigned long           busy_bits[1];   /* ports being reset or
56                                                         resumed */
57 #if USB_MAXCHILDREN > 31 /* 8*sizeof(unsigned long) - 1 */
58 #error event_bits[] is too short!
59 #endif
60
61         struct usb_hub_descriptor *descriptor;  /* class descriptor */
62         struct usb_tt           tt;             /* Transaction Translator */
63
64         unsigned                mA_per_port;    /* current for each child */
65
66         unsigned                limited_power:1;
67         unsigned                quiescing:1;
68         unsigned                activating:1;
69
70         unsigned                has_indicators:1;
71         u8                      indicator[USB_MAXCHILDREN];
72         struct delayed_work     leds;
73 };
74
75
76 /* Protect struct usb_device->state and ->children members
77  * Note: Both are also protected by ->dev.sem, except that ->state can
78  * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
79 static DEFINE_SPINLOCK(device_state_lock);
80
81 /* khubd's worklist and its lock */
82 static DEFINE_SPINLOCK(hub_event_lock);
83 static LIST_HEAD(hub_event_list);       /* List of hubs needing servicing */
84
85 /* Wakes up khubd */
86 static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
87
88 static struct task_struct *khubd_task;
89
90 /* cycle leds on hubs that aren't blinking for attention */
91 static int blinkenlights = 0;
92 module_param (blinkenlights, bool, S_IRUGO);
93 MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
94
95 /*
96  * As of 2.6.10 we introduce a new USB device initialization scheme which
97  * closely resembles the way Windows works.  Hopefully it will be compatible
98  * with a wider range of devices than the old scheme.  However some previously
99  * working devices may start giving rise to "device not accepting address"
100  * errors; if that happens the user can try the old scheme by adjusting the
101  * following module parameters.
102  *
103  * For maximum flexibility there are two boolean parameters to control the
104  * hub driver's behavior.  On the first initialization attempt, if the
105  * "old_scheme_first" parameter is set then the old scheme will be used,
106  * otherwise the new scheme is used.  If that fails and "use_both_schemes"
107  * is set, then the driver will make another attempt, using the other scheme.
108  */
109 static int old_scheme_first = 0;
110 module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
111 MODULE_PARM_DESC(old_scheme_first,
112                  "start with the old device initialization scheme");
113
114 static int use_both_schemes = 1;
115 module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
116 MODULE_PARM_DESC(use_both_schemes,
117                 "try the other device initialization scheme if the "
118                 "first one fails");
119
120
121 #ifdef  DEBUG
122 static inline char *portspeed (int portstatus)
123 {
124         if (portstatus & (1 << USB_PORT_FEAT_HIGHSPEED))
125                 return "480 Mb/s";
126         else if (portstatus & (1 << USB_PORT_FEAT_LOWSPEED))
127                 return "1.5 Mb/s";
128         else
129                 return "12 Mb/s";
130 }
131 #endif
132
133 /* Note that hdev or one of its children must be locked! */
134 static inline struct usb_hub *hdev_to_hub(struct usb_device *hdev)
135 {
136         return usb_get_intfdata(hdev->actconfig->interface[0]);
137 }
138
139 /* USB 2.0 spec Section 11.24.4.5 */
140 static int get_hub_descriptor(struct usb_device *hdev, void *data, int size)
141 {
142         int i, ret;
143
144         for (i = 0; i < 3; i++) {
145                 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
146                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
147                         USB_DT_HUB << 8, 0, data, size,
148                         USB_CTRL_GET_TIMEOUT);
149                 if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
150                         return ret;
151         }
152         return -EINVAL;
153 }
154
155 /*
156  * USB 2.0 spec Section 11.24.2.1
157  */
158 static int clear_hub_feature(struct usb_device *hdev, int feature)
159 {
160         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
161                 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
162 }
163
164 /*
165  * USB 2.0 spec Section 11.24.2.2
166  */
167 static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
168 {
169         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
170                 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
171                 NULL, 0, 1000);
172 }
173
174 /*
175  * USB 2.0 spec Section 11.24.2.13
176  */
177 static int set_port_feature(struct usb_device *hdev, int port1, int feature)
178 {
179         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
180                 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
181                 NULL, 0, 1000);
182 }
183
184 /*
185  * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
186  * for info about using port indicators
187  */
188 static void set_port_led(
189         struct usb_hub *hub,
190         int port1,
191         int selector
192 )
193 {
194         int status = set_port_feature(hub->hdev, (selector << 8) | port1,
195                         USB_PORT_FEAT_INDICATOR);
196         if (status < 0)
197                 dev_dbg (hub->intfdev,
198                         "port %d indicator %s status %d\n",
199                         port1,
200                         ({ char *s; switch (selector) {
201                         case HUB_LED_AMBER: s = "amber"; break;
202                         case HUB_LED_GREEN: s = "green"; break;
203                         case HUB_LED_OFF: s = "off"; break;
204                         case HUB_LED_AUTO: s = "auto"; break;
205                         default: s = "??"; break;
206                         }; s; }),
207                         status);
208 }
209
210 #define LED_CYCLE_PERIOD        ((2*HZ)/3)
211
212 static void led_work (struct work_struct *work)
213 {
214         struct usb_hub          *hub =
215                 container_of(work, struct usb_hub, leds.work);
216         struct usb_device       *hdev = hub->hdev;
217         unsigned                i;
218         unsigned                changed = 0;
219         int                     cursor = -1;
220
221         if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
222                 return;
223
224         for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
225                 unsigned        selector, mode;
226
227                 /* 30%-50% duty cycle */
228
229                 switch (hub->indicator[i]) {
230                 /* cycle marker */
231                 case INDICATOR_CYCLE:
232                         cursor = i;
233                         selector = HUB_LED_AUTO;
234                         mode = INDICATOR_AUTO;
235                         break;
236                 /* blinking green = sw attention */
237                 case INDICATOR_GREEN_BLINK:
238                         selector = HUB_LED_GREEN;
239                         mode = INDICATOR_GREEN_BLINK_OFF;
240                         break;
241                 case INDICATOR_GREEN_BLINK_OFF:
242                         selector = HUB_LED_OFF;
243                         mode = INDICATOR_GREEN_BLINK;
244                         break;
245                 /* blinking amber = hw attention */
246                 case INDICATOR_AMBER_BLINK:
247                         selector = HUB_LED_AMBER;
248                         mode = INDICATOR_AMBER_BLINK_OFF;
249                         break;
250                 case INDICATOR_AMBER_BLINK_OFF:
251                         selector = HUB_LED_OFF;
252                         mode = INDICATOR_AMBER_BLINK;
253                         break;
254                 /* blink green/amber = reserved */
255                 case INDICATOR_ALT_BLINK:
256                         selector = HUB_LED_GREEN;
257                         mode = INDICATOR_ALT_BLINK_OFF;
258                         break;
259                 case INDICATOR_ALT_BLINK_OFF:
260                         selector = HUB_LED_AMBER;
261                         mode = INDICATOR_ALT_BLINK;
262                         break;
263                 default:
264                         continue;
265                 }
266                 if (selector != HUB_LED_AUTO)
267                         changed = 1;
268                 set_port_led(hub, i + 1, selector);
269                 hub->indicator[i] = mode;
270         }
271         if (!changed && blinkenlights) {
272                 cursor++;
273                 cursor %= hub->descriptor->bNbrPorts;
274                 set_port_led(hub, cursor + 1, HUB_LED_GREEN);
275                 hub->indicator[cursor] = INDICATOR_CYCLE;
276                 changed++;
277         }
278         if (changed)
279                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
280 }
281
282 /* use a short timeout for hub/port status fetches */
283 #define USB_STS_TIMEOUT         1000
284 #define USB_STS_RETRIES         5
285
286 /*
287  * USB 2.0 spec Section 11.24.2.6
288  */
289 static int get_hub_status(struct usb_device *hdev,
290                 struct usb_hub_status *data)
291 {
292         int i, status = -ETIMEDOUT;
293
294         for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
295                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
296                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
297                         data, sizeof(*data), USB_STS_TIMEOUT);
298         }
299         return status;
300 }
301
302 /*
303  * USB 2.0 spec Section 11.24.2.7
304  */
305 static int get_port_status(struct usb_device *hdev, int port1,
306                 struct usb_port_status *data)
307 {
308         int i, status = -ETIMEDOUT;
309
310         for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
311                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
312                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
313                         data, sizeof(*data), USB_STS_TIMEOUT);
314         }
315         return status;
316 }
317
318 static void kick_khubd(struct usb_hub *hub)
319 {
320         unsigned long   flags;
321
322         /* Suppress autosuspend until khubd runs */
323         to_usb_interface(hub->intfdev)->pm_usage_cnt = 1;
324
325         spin_lock_irqsave(&hub_event_lock, flags);
326         if (list_empty(&hub->event_list)) {
327                 list_add_tail(&hub->event_list, &hub_event_list);
328                 wake_up(&khubd_wait);
329         }
330         spin_unlock_irqrestore(&hub_event_lock, flags);
331 }
332
333 void usb_kick_khubd(struct usb_device *hdev)
334 {
335         kick_khubd(hdev_to_hub(hdev));
336 }
337
338
339 /* completion function, fires on port status changes and various faults */
340 static void hub_irq(struct urb *urb)
341 {
342         struct usb_hub *hub = urb->context;
343         int status;
344         int i;
345         unsigned long bits;
346
347         switch (urb->status) {
348         case -ENOENT:           /* synchronous unlink */
349         case -ECONNRESET:       /* async unlink */
350         case -ESHUTDOWN:        /* hardware going away */
351                 return;
352
353         default:                /* presumably an error */
354                 /* Cause a hub reset after 10 consecutive errors */
355                 dev_dbg (hub->intfdev, "transfer --> %d\n", urb->status);
356                 if ((++hub->nerrors < 10) || hub->error)
357                         goto resubmit;
358                 hub->error = urb->status;
359                 /* FALL THROUGH */
360
361         /* let khubd handle things */
362         case 0:                 /* we got data:  port status changed */
363                 bits = 0;
364                 for (i = 0; i < urb->actual_length; ++i)
365                         bits |= ((unsigned long) ((*hub->buffer)[i]))
366                                         << (i*8);
367                 hub->event_bits[0] = bits;
368                 break;
369         }
370
371         hub->nerrors = 0;
372
373         /* Something happened, let khubd figure it out */
374         kick_khubd(hub);
375
376 resubmit:
377         if (hub->quiescing)
378                 return;
379
380         if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
381                         && status != -ENODEV && status != -EPERM)
382                 dev_err (hub->intfdev, "resubmit --> %d\n", status);
383 }
384
385 /* USB 2.0 spec Section 11.24.2.3 */
386 static inline int
387 hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
388 {
389         return usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
390                                HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
391                                tt, NULL, 0, 1000);
392 }
393
394 /*
395  * enumeration blocks khubd for a long time. we use keventd instead, since
396  * long blocking there is the exception, not the rule.  accordingly, HCDs
397  * talking to TTs must queue control transfers (not just bulk and iso), so
398  * both can talk to the same hub concurrently.
399  */
400 static void hub_tt_kevent (struct work_struct *work)
401 {
402         struct usb_hub          *hub =
403                 container_of(work, struct usb_hub, tt.kevent);
404         unsigned long           flags;
405
406         spin_lock_irqsave (&hub->tt.lock, flags);
407         while (!list_empty (&hub->tt.clear_list)) {
408                 struct list_head        *temp;
409                 struct usb_tt_clear     *clear;
410                 struct usb_device       *hdev = hub->hdev;
411                 int                     status;
412
413                 temp = hub->tt.clear_list.next;
414                 clear = list_entry (temp, struct usb_tt_clear, clear_list);
415                 list_del (&clear->clear_list);
416
417                 /* drop lock so HCD can concurrently report other TT errors */
418                 spin_unlock_irqrestore (&hub->tt.lock, flags);
419                 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
420                 spin_lock_irqsave (&hub->tt.lock, flags);
421
422                 if (status)
423                         dev_err (&hdev->dev,
424                                 "clear tt %d (%04x) error %d\n",
425                                 clear->tt, clear->devinfo, status);
426                 kfree(clear);
427         }
428         spin_unlock_irqrestore (&hub->tt.lock, flags);
429 }
430
431 /**
432  * usb_hub_tt_clear_buffer - clear control/bulk TT state in high speed hub
433  * @udev: the device whose split transaction failed
434  * @pipe: identifies the endpoint of the failed transaction
435  *
436  * High speed HCDs use this to tell the hub driver that some split control or
437  * bulk transaction failed in a way that requires clearing internal state of
438  * a transaction translator.  This is normally detected (and reported) from
439  * interrupt context.
440  *
441  * It may not be possible for that hub to handle additional full (or low)
442  * speed transactions until that state is fully cleared out.
443  */
444 void usb_hub_tt_clear_buffer (struct usb_device *udev, int pipe)
445 {
446         struct usb_tt           *tt = udev->tt;
447         unsigned long           flags;
448         struct usb_tt_clear     *clear;
449
450         /* we've got to cope with an arbitrary number of pending TT clears,
451          * since each TT has "at least two" buffers that can need it (and
452          * there can be many TTs per hub).  even if they're uncommon.
453          */
454         if ((clear = kmalloc (sizeof *clear, GFP_ATOMIC)) == NULL) {
455                 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
456                 /* FIXME recover somehow ... RESET_TT? */
457                 return;
458         }
459
460         /* info that CLEAR_TT_BUFFER needs */
461         clear->tt = tt->multi ? udev->ttport : 1;
462         clear->devinfo = usb_pipeendpoint (pipe);
463         clear->devinfo |= udev->devnum << 4;
464         clear->devinfo |= usb_pipecontrol (pipe)
465                         ? (USB_ENDPOINT_XFER_CONTROL << 11)
466                         : (USB_ENDPOINT_XFER_BULK << 11);
467         if (usb_pipein (pipe))
468                 clear->devinfo |= 1 << 15;
469         
470         /* tell keventd to clear state for this TT */
471         spin_lock_irqsave (&tt->lock, flags);
472         list_add_tail (&clear->clear_list, &tt->clear_list);
473         schedule_work (&tt->kevent);
474         spin_unlock_irqrestore (&tt->lock, flags);
475 }
476
477 static void hub_power_on(struct usb_hub *hub)
478 {
479         int port1;
480         unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
481         u16 wHubCharacteristics =
482                         le16_to_cpu(hub->descriptor->wHubCharacteristics);
483
484         /* Enable power on each port.  Some hubs have reserved values
485          * of LPSM (> 2) in their descriptors, even though they are
486          * USB 2.0 hubs.  Some hubs do not implement port-power switching
487          * but only emulate it.  In all cases, the ports won't work
488          * unless we send these messages to the hub.
489          */
490         if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2)
491                 dev_dbg(hub->intfdev, "enabling power on all ports\n");
492         else
493                 dev_dbg(hub->intfdev, "trying to enable port power on "
494                                 "non-switchable hub\n");
495         for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
496                 set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
497
498         /* Wait at least 100 msec for power to become stable */
499         msleep(max(pgood_delay, (unsigned) 100));
500 }
501
502 static void hub_quiesce(struct usb_hub *hub)
503 {
504         /* (nonblocking) khubd and related activity won't re-trigger */
505         hub->quiescing = 1;
506         hub->activating = 0;
507
508         /* (blocking) stop khubd and related activity */
509         usb_kill_urb(hub->urb);
510         if (hub->has_indicators)
511                 cancel_delayed_work(&hub->leds);
512         if (hub->has_indicators || hub->tt.hub)
513                 flush_scheduled_work();
514 }
515
516 static void hub_activate(struct usb_hub *hub)
517 {
518         int     status;
519
520         hub->quiescing = 0;
521         hub->activating = 1;
522
523         status = usb_submit_urb(hub->urb, GFP_NOIO);
524         if (status < 0)
525                 dev_err(hub->intfdev, "activate --> %d\n", status);
526         if (hub->has_indicators && blinkenlights)
527                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
528
529         /* scan all ports ASAP */
530         kick_khubd(hub);
531 }
532
533 static int hub_hub_status(struct usb_hub *hub,
534                 u16 *status, u16 *change)
535 {
536         int ret;
537
538         ret = get_hub_status(hub->hdev, &hub->status->hub);
539         if (ret < 0)
540                 dev_err (hub->intfdev,
541                         "%s failed (err = %d)\n", __FUNCTION__, ret);
542         else {
543                 *status = le16_to_cpu(hub->status->hub.wHubStatus);
544                 *change = le16_to_cpu(hub->status->hub.wHubChange); 
545                 ret = 0;
546         }
547         return ret;
548 }
549
550 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
551 {
552         struct usb_device *hdev = hub->hdev;
553         int ret;
554
555         if (hdev->children[port1-1] && set_state) {
556                 usb_set_device_state(hdev->children[port1-1],
557                                 USB_STATE_NOTATTACHED);
558         }
559         ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
560         if (ret)
561                 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
562                         port1, ret);
563
564         return ret;
565 }
566
567
568 /* caller has locked the hub device */
569 static void hub_pre_reset(struct usb_interface *intf)
570 {
571         struct usb_hub *hub = usb_get_intfdata(intf);
572         struct usb_device *hdev = hub->hdev;
573         int port1;
574
575         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
576                 if (hdev->children[port1 - 1]) {
577                         usb_disconnect(&hdev->children[port1 - 1]);
578                         if (hub->error == 0)
579                                 hub_port_disable(hub, port1, 0);
580                 }
581         }
582         hub_quiesce(hub);
583 }
584
585 /* caller has locked the hub device */
586 static void hub_post_reset(struct usb_interface *intf)
587 {
588         struct usb_hub *hub = usb_get_intfdata(intf);
589
590         hub_activate(hub);
591         hub_power_on(hub);
592 }
593
594
595 static int hub_configure(struct usb_hub *hub,
596         struct usb_endpoint_descriptor *endpoint)
597 {
598         struct usb_device *hdev = hub->hdev;
599         struct device *hub_dev = hub->intfdev;
600         u16 hubstatus, hubchange;
601         u16 wHubCharacteristics;
602         unsigned int pipe;
603         int maxp, ret;
604         char *message;
605
606         hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
607                         &hub->buffer_dma);
608         if (!hub->buffer) {
609                 message = "can't allocate hub irq buffer";
610                 ret = -ENOMEM;
611                 goto fail;
612         }
613
614         hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
615         if (!hub->status) {
616                 message = "can't kmalloc hub status buffer";
617                 ret = -ENOMEM;
618                 goto fail;
619         }
620
621         hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
622         if (!hub->descriptor) {
623                 message = "can't kmalloc hub descriptor";
624                 ret = -ENOMEM;
625                 goto fail;
626         }
627
628         /* Request the entire hub descriptor.
629          * hub->descriptor can handle USB_MAXCHILDREN ports,
630          * but the hub can/will return fewer bytes here.
631          */
632         ret = get_hub_descriptor(hdev, hub->descriptor,
633                         sizeof(*hub->descriptor));
634         if (ret < 0) {
635                 message = "can't read hub descriptor";
636                 goto fail;
637         } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
638                 message = "hub has too many ports!";
639                 ret = -ENODEV;
640                 goto fail;
641         }
642
643         hdev->maxchild = hub->descriptor->bNbrPorts;
644         dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
645                 (hdev->maxchild == 1) ? "" : "s");
646
647         wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
648
649         if (wHubCharacteristics & HUB_CHAR_COMPOUND) {
650                 int     i;
651                 char    portstr [USB_MAXCHILDREN + 1];
652
653                 for (i = 0; i < hdev->maxchild; i++)
654                         portstr[i] = hub->descriptor->DeviceRemovable
655                                     [((i + 1) / 8)] & (1 << ((i + 1) % 8))
656                                 ? 'F' : 'R';
657                 portstr[hdev->maxchild] = 0;
658                 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
659         } else
660                 dev_dbg(hub_dev, "standalone hub\n");
661
662         switch (wHubCharacteristics & HUB_CHAR_LPSM) {
663                 case 0x00:
664                         dev_dbg(hub_dev, "ganged power switching\n");
665                         break;
666                 case 0x01:
667                         dev_dbg(hub_dev, "individual port power switching\n");
668                         break;
669                 case 0x02:
670                 case 0x03:
671                         dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
672                         break;
673         }
674
675         switch (wHubCharacteristics & HUB_CHAR_OCPM) {
676                 case 0x00:
677                         dev_dbg(hub_dev, "global over-current protection\n");
678                         break;
679                 case 0x08:
680                         dev_dbg(hub_dev, "individual port over-current protection\n");
681                         break;
682                 case 0x10:
683                 case 0x18:
684                         dev_dbg(hub_dev, "no over-current protection\n");
685                         break;
686         }
687
688         spin_lock_init (&hub->tt.lock);
689         INIT_LIST_HEAD (&hub->tt.clear_list);
690         INIT_WORK (&hub->tt.kevent, hub_tt_kevent);
691         switch (hdev->descriptor.bDeviceProtocol) {
692                 case 0:
693                         break;
694                 case 1:
695                         dev_dbg(hub_dev, "Single TT\n");
696                         hub->tt.hub = hdev;
697                         break;
698                 case 2:
699                         ret = usb_set_interface(hdev, 0, 1);
700                         if (ret == 0) {
701                                 dev_dbg(hub_dev, "TT per port\n");
702                                 hub->tt.multi = 1;
703                         } else
704                                 dev_err(hub_dev, "Using single TT (err %d)\n",
705                                         ret);
706                         hub->tt.hub = hdev;
707                         break;
708                 default:
709                         dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
710                                 hdev->descriptor.bDeviceProtocol);
711                         break;
712         }
713
714         /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
715         switch (wHubCharacteristics & HUB_CHAR_TTTT) {
716                 case HUB_TTTT_8_BITS:
717                         if (hdev->descriptor.bDeviceProtocol != 0) {
718                                 hub->tt.think_time = 666;
719                                 dev_dbg(hub_dev, "TT requires at most %d "
720                                                 "FS bit times (%d ns)\n",
721                                         8, hub->tt.think_time);
722                         }
723                         break;
724                 case HUB_TTTT_16_BITS:
725                         hub->tt.think_time = 666 * 2;
726                         dev_dbg(hub_dev, "TT requires at most %d "
727                                         "FS bit times (%d ns)\n",
728                                 16, hub->tt.think_time);
729                         break;
730                 case HUB_TTTT_24_BITS:
731                         hub->tt.think_time = 666 * 3;
732                         dev_dbg(hub_dev, "TT requires at most %d "
733                                         "FS bit times (%d ns)\n",
734                                 24, hub->tt.think_time);
735                         break;
736                 case HUB_TTTT_32_BITS:
737                         hub->tt.think_time = 666 * 4;
738                         dev_dbg(hub_dev, "TT requires at most %d "
739                                         "FS bit times (%d ns)\n",
740                                 32, hub->tt.think_time);
741                         break;
742         }
743
744         /* probe() zeroes hub->indicator[] */
745         if (wHubCharacteristics & HUB_CHAR_PORTIND) {
746                 hub->has_indicators = 1;
747                 dev_dbg(hub_dev, "Port indicators are supported\n");
748         }
749
750         dev_dbg(hub_dev, "power on to power good time: %dms\n",
751                 hub->descriptor->bPwrOn2PwrGood * 2);
752
753         /* power budgeting mostly matters with bus-powered hubs,
754          * and battery-powered root hubs (may provide just 8 mA).
755          */
756         ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
757         if (ret < 2) {
758                 message = "can't get hub status";
759                 goto fail;
760         }
761         le16_to_cpus(&hubstatus);
762         if (hdev == hdev->bus->root_hub) {
763                 if (hdev->bus_mA == 0 || hdev->bus_mA >= 500)
764                         hub->mA_per_port = 500;
765                 else {
766                         hub->mA_per_port = hdev->bus_mA;
767                         hub->limited_power = 1;
768                 }
769         } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
770                 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
771                         hub->descriptor->bHubContrCurrent);
772                 hub->limited_power = 1;
773                 if (hdev->maxchild > 0) {
774                         int remaining = hdev->bus_mA -
775                                         hub->descriptor->bHubContrCurrent;
776
777                         if (remaining < hdev->maxchild * 100)
778                                 dev_warn(hub_dev,
779                                         "insufficient power available "
780                                         "to use all downstream ports\n");
781                         hub->mA_per_port = 100;         /* 7.2.1.1 */
782                 }
783         } else {        /* Self-powered external hub */
784                 /* FIXME: What about battery-powered external hubs that
785                  * provide less current per port? */
786                 hub->mA_per_port = 500;
787         }
788         if (hub->mA_per_port < 500)
789                 dev_dbg(hub_dev, "%umA bus power budget for each child\n",
790                                 hub->mA_per_port);
791
792         ret = hub_hub_status(hub, &hubstatus, &hubchange);
793         if (ret < 0) {
794                 message = "can't get hub status";
795                 goto fail;
796         }
797
798         /* local power status reports aren't always correct */
799         if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
800                 dev_dbg(hub_dev, "local power source is %s\n",
801                         (hubstatus & HUB_STATUS_LOCAL_POWER)
802                         ? "lost (inactive)" : "good");
803
804         if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
805                 dev_dbg(hub_dev, "%sover-current condition exists\n",
806                         (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
807
808         /* set up the interrupt endpoint
809          * We use the EP's maxpacket size instead of (PORTS+1+7)/8
810          * bytes as USB2.0[11.12.3] says because some hubs are known
811          * to send more data (and thus cause overflow). For root hubs,
812          * maxpktsize is defined in hcd.c's fake endpoint descriptors
813          * to be big enough for at least USB_MAXCHILDREN ports. */
814         pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
815         maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
816
817         if (maxp > sizeof(*hub->buffer))
818                 maxp = sizeof(*hub->buffer);
819
820         hub->urb = usb_alloc_urb(0, GFP_KERNEL);
821         if (!hub->urb) {
822                 message = "couldn't allocate interrupt urb";
823                 ret = -ENOMEM;
824                 goto fail;
825         }
826
827         usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
828                 hub, endpoint->bInterval);
829         hub->urb->transfer_dma = hub->buffer_dma;
830         hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
831
832         /* maybe cycle the hub leds */
833         if (hub->has_indicators && blinkenlights)
834                 hub->indicator [0] = INDICATOR_CYCLE;
835
836         hub_power_on(hub);
837         hub_activate(hub);
838         return 0;
839
840 fail:
841         dev_err (hub_dev, "config failed, %s (err %d)\n",
842                         message, ret);
843         /* hub_disconnect() frees urb and descriptor */
844         return ret;
845 }
846
847 static unsigned highspeed_hubs;
848
849 static void hub_disconnect(struct usb_interface *intf)
850 {
851         struct usb_hub *hub = usb_get_intfdata (intf);
852         struct usb_device *hdev;
853
854         /* Disconnect all children and quiesce the hub */
855         hub->error = 0;
856         hub_pre_reset(intf);
857
858         usb_set_intfdata (intf, NULL);
859         hdev = hub->hdev;
860
861         if (hdev->speed == USB_SPEED_HIGH)
862                 highspeed_hubs--;
863
864         usb_free_urb(hub->urb);
865         hub->urb = NULL;
866
867         spin_lock_irq(&hub_event_lock);
868         list_del_init(&hub->event_list);
869         spin_unlock_irq(&hub_event_lock);
870
871         kfree(hub->descriptor);
872         hub->descriptor = NULL;
873
874         kfree(hub->status);
875         hub->status = NULL;
876
877         if (hub->buffer) {
878                 usb_buffer_free(hdev, sizeof(*hub->buffer), hub->buffer,
879                                 hub->buffer_dma);
880                 hub->buffer = NULL;
881         }
882
883         kfree(hub);
884 }
885
886 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
887 {
888         struct usb_host_interface *desc;
889         struct usb_endpoint_descriptor *endpoint;
890         struct usb_device *hdev;
891         struct usb_hub *hub;
892
893         desc = intf->cur_altsetting;
894         hdev = interface_to_usbdev(intf);
895
896 #ifdef  CONFIG_USB_OTG_BLACKLIST_HUB
897         if (hdev->parent) {
898                 dev_warn(&intf->dev, "ignoring external hub\n");
899                 return -ENODEV;
900         }
901 #endif
902
903         /* Some hubs have a subclass of 1, which AFAICT according to the */
904         /*  specs is not defined, but it works */
905         if ((desc->desc.bInterfaceSubClass != 0) &&
906             (desc->desc.bInterfaceSubClass != 1)) {
907 descriptor_error:
908                 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
909                 return -EIO;
910         }
911
912         /* Multiple endpoints? What kind of mutant ninja-hub is this? */
913         if (desc->desc.bNumEndpoints != 1)
914                 goto descriptor_error;
915
916         endpoint = &desc->endpoint[0].desc;
917
918         /* If it's not an interrupt in endpoint, we'd better punt! */
919         if (!usb_endpoint_is_int_in(endpoint))
920                 goto descriptor_error;
921
922         /* We found a hub */
923         dev_info (&intf->dev, "USB hub found\n");
924
925         hub = kzalloc(sizeof(*hub), GFP_KERNEL);
926         if (!hub) {
927                 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
928                 return -ENOMEM;
929         }
930
931         INIT_LIST_HEAD(&hub->event_list);
932         hub->intfdev = &intf->dev;
933         hub->hdev = hdev;
934         INIT_DELAYED_WORK(&hub->leds, led_work);
935
936         usb_set_intfdata (intf, hub);
937         intf->needs_remote_wakeup = 1;
938
939         if (hdev->speed == USB_SPEED_HIGH)
940                 highspeed_hubs++;
941
942         if (hub_configure(hub, endpoint) >= 0)
943                 return 0;
944
945         hub_disconnect (intf);
946         return -ENODEV;
947 }
948
949 static int
950 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
951 {
952         struct usb_device *hdev = interface_to_usbdev (intf);
953
954         /* assert ifno == 0 (part of hub spec) */
955         switch (code) {
956         case USBDEVFS_HUB_PORTINFO: {
957                 struct usbdevfs_hub_portinfo *info = user_data;
958                 int i;
959
960                 spin_lock_irq(&device_state_lock);
961                 if (hdev->devnum <= 0)
962                         info->nports = 0;
963                 else {
964                         info->nports = hdev->maxchild;
965                         for (i = 0; i < info->nports; i++) {
966                                 if (hdev->children[i] == NULL)
967                                         info->port[i] = 0;
968                                 else
969                                         info->port[i] =
970                                                 hdev->children[i]->devnum;
971                         }
972                 }
973                 spin_unlock_irq(&device_state_lock);
974
975                 return info->nports + 1;
976                 }
977
978         default:
979                 return -ENOSYS;
980         }
981 }
982
983
984 /* grab device/port lock, returning index of that port (zero based).
985  * protects the upstream link used by this device from concurrent
986  * tree operations like suspend, resume, reset, and disconnect, which
987  * apply to everything downstream of a given port.
988  */
989 static int locktree(struct usb_device *udev)
990 {
991         int                     t;
992         struct usb_device       *hdev;
993
994         if (!udev)
995                 return -ENODEV;
996
997         /* root hub is always the first lock in the series */
998         hdev = udev->parent;
999         if (!hdev) {
1000                 usb_lock_device(udev);
1001                 return 0;
1002         }
1003
1004         /* on the path from root to us, lock everything from
1005          * top down, dropping parent locks when not needed
1006          */
1007         t = locktree(hdev);
1008         if (t < 0)
1009                 return t;
1010
1011         /* everything is fail-fast once disconnect
1012          * processing starts
1013          */
1014         if (udev->state == USB_STATE_NOTATTACHED) {
1015                 usb_unlock_device(hdev);
1016                 return -ENODEV;
1017         }
1018
1019         /* when everyone grabs locks top->bottom,
1020          * non-overlapping work may be concurrent
1021          */
1022         usb_lock_device(udev);
1023         usb_unlock_device(hdev);
1024         return udev->portnum;
1025 }
1026
1027 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
1028 {
1029         int i;
1030
1031         for (i = 0; i < udev->maxchild; ++i) {
1032                 if (udev->children[i])
1033                         recursively_mark_NOTATTACHED(udev->children[i]);
1034         }
1035         if (udev->state == USB_STATE_SUSPENDED)
1036                 udev->discon_suspended = 1;
1037         udev->state = USB_STATE_NOTATTACHED;
1038 }
1039
1040 /**
1041  * usb_set_device_state - change a device's current state (usbcore, hcds)
1042  * @udev: pointer to device whose state should be changed
1043  * @new_state: new state value to be stored
1044  *
1045  * udev->state is _not_ fully protected by the device lock.  Although
1046  * most transitions are made only while holding the lock, the state can
1047  * can change to USB_STATE_NOTATTACHED at almost any time.  This
1048  * is so that devices can be marked as disconnected as soon as possible,
1049  * without having to wait for any semaphores to be released.  As a result,
1050  * all changes to any device's state must be protected by the
1051  * device_state_lock spinlock.
1052  *
1053  * Once a device has been added to the device tree, all changes to its state
1054  * should be made using this routine.  The state should _not_ be set directly.
1055  *
1056  * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1057  * Otherwise udev->state is set to new_state, and if new_state is
1058  * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1059  * to USB_STATE_NOTATTACHED.
1060  */
1061 void usb_set_device_state(struct usb_device *udev,
1062                 enum usb_device_state new_state)
1063 {
1064         unsigned long flags;
1065
1066         spin_lock_irqsave(&device_state_lock, flags);
1067         if (udev->state == USB_STATE_NOTATTACHED)
1068                 ;       /* do nothing */
1069         else if (new_state != USB_STATE_NOTATTACHED) {
1070
1071                 /* root hub wakeup capabilities are managed out-of-band
1072                  * and may involve silicon errata ... ignore them here.
1073                  */
1074                 if (udev->parent) {
1075                         if (udev->state == USB_STATE_SUSPENDED
1076                                         || new_state == USB_STATE_SUSPENDED)
1077                                 ;       /* No change to wakeup settings */
1078                         else if (new_state == USB_STATE_CONFIGURED)
1079                                 device_init_wakeup(&udev->dev,
1080                                         (udev->actconfig->desc.bmAttributes
1081                                          & USB_CONFIG_ATT_WAKEUP));
1082                         else
1083                                 device_init_wakeup(&udev->dev, 0);
1084                 }
1085                 udev->state = new_state;
1086         } else
1087                 recursively_mark_NOTATTACHED(udev);
1088         spin_unlock_irqrestore(&device_state_lock, flags);
1089 }
1090
1091
1092 #ifdef  CONFIG_PM
1093
1094 /**
1095  * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
1096  * @rhdev: struct usb_device for the root hub
1097  *
1098  * The USB host controller driver calls this function when its root hub
1099  * is resumed and Vbus power has been interrupted or the controller
1100  * has been reset.  The routine marks all the children of the root hub
1101  * as NOTATTACHED and marks logical connect-change events on their ports.
1102  */
1103 void usb_root_hub_lost_power(struct usb_device *rhdev)
1104 {
1105         struct usb_hub *hub;
1106         int port1;
1107         unsigned long flags;
1108
1109         dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
1110
1111         /* Make sure no potential wakeup events get lost,
1112          * by forcing the root hub to be resumed.
1113          */
1114         rhdev->dev.power.prev_state.event = PM_EVENT_ON;
1115
1116         spin_lock_irqsave(&device_state_lock, flags);
1117         hub = hdev_to_hub(rhdev);
1118         for (port1 = 1; port1 <= rhdev->maxchild; ++port1) {
1119                 if (rhdev->children[port1 - 1]) {
1120                         recursively_mark_NOTATTACHED(
1121                                         rhdev->children[port1 - 1]);
1122                         set_bit(port1, hub->change_bits);
1123                 }
1124         }
1125         spin_unlock_irqrestore(&device_state_lock, flags);
1126 }
1127 EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
1128
1129 #endif  /* CONFIG_PM */
1130
1131 static void choose_address(struct usb_device *udev)
1132 {
1133         int             devnum;
1134         struct usb_bus  *bus = udev->bus;
1135
1136         /* If khubd ever becomes multithreaded, this will need a lock */
1137
1138         /* Try to allocate the next devnum beginning at bus->devnum_next. */
1139         devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1140                         bus->devnum_next);
1141         if (devnum >= 128)
1142                 devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
1143
1144         bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1145
1146         if (devnum < 128) {
1147                 set_bit(devnum, bus->devmap.devicemap);
1148                 udev->devnum = devnum;
1149         }
1150 }
1151
1152 static void release_address(struct usb_device *udev)
1153 {
1154         if (udev->devnum > 0) {
1155                 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1156                 udev->devnum = -1;
1157         }
1158 }
1159
1160 /**
1161  * usb_disconnect - disconnect a device (usbcore-internal)
1162  * @pdev: pointer to device being disconnected
1163  * Context: !in_interrupt ()
1164  *
1165  * Something got disconnected. Get rid of it and all of its children.
1166  *
1167  * If *pdev is a normal device then the parent hub must already be locked.
1168  * If *pdev is a root hub then this routine will acquire the
1169  * usb_bus_list_lock on behalf of the caller.
1170  *
1171  * Only hub drivers (including virtual root hub drivers for host
1172  * controllers) should ever call this.
1173  *
1174  * This call is synchronous, and may not be used in an interrupt context.
1175  */
1176 void usb_disconnect(struct usb_device **pdev)
1177 {
1178         struct usb_device       *udev = *pdev;
1179         int                     i;
1180
1181         if (!udev) {
1182                 pr_debug ("%s nodev\n", __FUNCTION__);
1183                 return;
1184         }
1185
1186         /* mark the device as inactive, so any further urb submissions for
1187          * this device (and any of its children) will fail immediately.
1188          * this quiesces everyting except pending urbs.
1189          */
1190         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1191         dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1192
1193         usb_lock_device(udev);
1194
1195         /* Free up all the children before we remove this device */
1196         for (i = 0; i < USB_MAXCHILDREN; i++) {
1197                 if (udev->children[i])
1198                         usb_disconnect(&udev->children[i]);
1199         }
1200
1201         /* deallocate hcd/hardware state ... nuking all pending urbs and
1202          * cleaning up all state associated with the current configuration
1203          * so that the hardware is now fully quiesced.
1204          */
1205         dev_dbg (&udev->dev, "unregistering device\n");
1206         usb_disable_device(udev, 0);
1207
1208         usb_unlock_device(udev);
1209
1210         /* Unregister the device.  The device driver is responsible
1211          * for removing the device files from usbfs and sysfs and for
1212          * de-configuring the device.
1213          */
1214         device_del(&udev->dev);
1215
1216         /* Free the device number and delete the parent's children[]
1217          * (or root_hub) pointer.
1218          */
1219         release_address(udev);
1220
1221         /* Avoid races with recursively_mark_NOTATTACHED() */
1222         spin_lock_irq(&device_state_lock);
1223         *pdev = NULL;
1224         spin_unlock_irq(&device_state_lock);
1225
1226         /* Decrement the parent's count of unsuspended children */
1227         if (udev->parent) {
1228                 usb_pm_lock(udev);
1229                 if (!udev->discon_suspended)
1230                         usb_autosuspend_device(udev->parent);
1231                 usb_pm_unlock(udev);
1232         }
1233
1234         put_device(&udev->dev);
1235 }
1236
1237 #ifdef DEBUG
1238 static void show_string(struct usb_device *udev, char *id, char *string)
1239 {
1240         if (!string)
1241                 return;
1242         dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1243 }
1244
1245 #else
1246 static inline void show_string(struct usb_device *udev, char *id, char *string)
1247 {}
1248 #endif
1249
1250
1251 #ifdef  CONFIG_USB_OTG
1252 #include "otg_whitelist.h"
1253 static int __usb_port_suspend(struct usb_device *, int port1);
1254 #endif
1255
1256 /**
1257  * usb_new_device - perform initial device setup (usbcore-internal)
1258  * @udev: newly addressed device (in ADDRESS state)
1259  *
1260  * This is called with devices which have been enumerated, but not yet
1261  * configured.  The device descriptor is available, but not descriptors
1262  * for any device configuration.  The caller must have locked either
1263  * the parent hub (if udev is a normal device) or else the
1264  * usb_bus_list_lock (if udev is a root hub).  The parent's pointer to
1265  * udev has already been installed, but udev is not yet visible through
1266  * sysfs or other filesystem code.
1267  *
1268  * It will return if the device is configured properly or not.  Zero if
1269  * the interface was registered with the driver core; else a negative
1270  * errno value.
1271  *
1272  * This call is synchronous, and may not be used in an interrupt context.
1273  *
1274  * Only the hub driver or root-hub registrar should ever call this.
1275  */
1276 int usb_new_device(struct usb_device *udev)
1277 {
1278         int err;
1279
1280         /* Lock ourself into memory in order to keep a probe sequence
1281          * sleeping in a new thread from allowing us to be unloaded.
1282          */
1283         if (!try_module_get(THIS_MODULE))
1284                 return -EINVAL;
1285
1286         err = usb_get_configuration(udev);
1287         if (err < 0) {
1288                 dev_err(&udev->dev, "can't read configurations, error %d\n",
1289                         err);
1290                 goto fail;
1291         }
1292
1293         /* read the standard strings and cache them if present */
1294         udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
1295         udev->manufacturer = usb_cache_string(udev,
1296                         udev->descriptor.iManufacturer);
1297         udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
1298
1299         /* Tell the world! */
1300         dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
1301                         "SerialNumber=%d\n",
1302                         udev->descriptor.iManufacturer,
1303                         udev->descriptor.iProduct,
1304                         udev->descriptor.iSerialNumber);
1305         show_string(udev, "Product", udev->product);
1306         show_string(udev, "Manufacturer", udev->manufacturer);
1307         show_string(udev, "SerialNumber", udev->serial);
1308
1309 #ifdef  CONFIG_USB_OTG
1310         /*
1311          * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1312          * to wake us after we've powered off VBUS; and HNP, switching roles
1313          * "host" to "peripheral".  The OTG descriptor helps figure this out.
1314          */
1315         if (!udev->bus->is_b_host
1316                         && udev->config
1317                         && udev->parent == udev->bus->root_hub) {
1318                 struct usb_otg_descriptor       *desc = 0;
1319                 struct usb_bus                  *bus = udev->bus;
1320
1321                 /* descriptor may appear anywhere in config */
1322                 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1323                                         le16_to_cpu(udev->config[0].desc.wTotalLength),
1324                                         USB_DT_OTG, (void **) &desc) == 0) {
1325                         if (desc->bmAttributes & USB_OTG_HNP) {
1326                                 unsigned                port1 = udev->portnum;
1327
1328                                 dev_info(&udev->dev,
1329                                         "Dual-Role OTG device on %sHNP port\n",
1330                                         (port1 == bus->otg_port)
1331                                                 ? "" : "non-");
1332
1333                                 /* enable HNP before suspend, it's simpler */
1334                                 if (port1 == bus->otg_port)
1335                                         bus->b_hnp_enable = 1;
1336                                 err = usb_control_msg(udev,
1337                                         usb_sndctrlpipe(udev, 0),
1338                                         USB_REQ_SET_FEATURE, 0,
1339                                         bus->b_hnp_enable
1340                                                 ? USB_DEVICE_B_HNP_ENABLE
1341                                                 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1342                                         0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1343                                 if (err < 0) {
1344                                         /* OTG MESSAGE: report errors here,
1345                                          * customize to match your product.
1346                                          */
1347                                         dev_info(&udev->dev,
1348                                                 "can't set HNP mode; %d\n",
1349                                                 err);
1350                                         bus->b_hnp_enable = 0;
1351                                 }
1352                         }
1353                 }
1354         }
1355
1356         if (!is_targeted(udev)) {
1357
1358                 /* Maybe it can talk to us, though we can't talk to it.
1359                  * (Includes HNP test device.)
1360                  */
1361                 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1362                         err = __usb_port_suspend(udev, udev->bus->otg_port);
1363                         if (err < 0)
1364                                 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1365                 }
1366                 err = -ENODEV;
1367                 goto fail;
1368         }
1369 #endif
1370
1371         /* Register the device.  The device driver is responsible
1372          * for adding the device files to usbfs and sysfs and for
1373          * configuring the device.
1374          */
1375         err = device_add (&udev->dev);
1376         if (err) {
1377                 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1378                 goto fail;
1379         }
1380
1381         /* Increment the parent's count of unsuspended children */
1382         if (udev->parent)
1383                 usb_autoresume_device(udev->parent);
1384
1385 exit:
1386         module_put(THIS_MODULE);
1387         return err;
1388
1389 fail:
1390         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1391         goto exit;
1392 }
1393
1394 static int hub_port_status(struct usb_hub *hub, int port1,
1395                                u16 *status, u16 *change)
1396 {
1397         int ret;
1398
1399         ret = get_port_status(hub->hdev, port1, &hub->status->port);
1400         if (ret < 4) {
1401                 dev_err (hub->intfdev,
1402                         "%s failed (err = %d)\n", __FUNCTION__, ret);
1403                 if (ret >= 0)
1404                         ret = -EIO;
1405         } else {
1406                 *status = le16_to_cpu(hub->status->port.wPortStatus);
1407                 *change = le16_to_cpu(hub->status->port.wPortChange); 
1408                 ret = 0;
1409         }
1410         return ret;
1411 }
1412
1413
1414 /* Returns 1 if @hub is a WUSB root hub, 0 otherwise */
1415 static unsigned hub_is_wusb(struct usb_hub *hub)
1416 {
1417         struct usb_hcd *hcd;
1418         if (hub->hdev->parent != NULL)  /* not a root hub? */
1419                 return 0;
1420         hcd = container_of(hub->hdev->bus, struct usb_hcd, self);
1421         return hcd->wireless;
1422 }
1423
1424
1425 #define PORT_RESET_TRIES        5
1426 #define SET_ADDRESS_TRIES       2
1427 #define GET_DESCRIPTOR_TRIES    2
1428 #define SET_CONFIG_TRIES        (2 * (use_both_schemes + 1))
1429 #define USE_NEW_SCHEME(i)       ((i) / 2 == old_scheme_first)
1430
1431 #define HUB_ROOT_RESET_TIME     50      /* times are in msec */
1432 #define HUB_SHORT_RESET_TIME    10
1433 #define HUB_LONG_RESET_TIME     200
1434 #define HUB_RESET_TIMEOUT       500
1435
1436 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1437                                 struct usb_device *udev, unsigned int delay)
1438 {
1439         int delay_time, ret;
1440         u16 portstatus;
1441         u16 portchange;
1442
1443         for (delay_time = 0;
1444                         delay_time < HUB_RESET_TIMEOUT;
1445                         delay_time += delay) {
1446                 /* wait to give the device a chance to reset */
1447                 msleep(delay);
1448
1449                 /* read and decode port status */
1450                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1451                 if (ret < 0)
1452                         return ret;
1453
1454                 /* Device went away? */
1455                 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1456                         return -ENOTCONN;
1457
1458                 /* bomb out completely if something weird happened */
1459                 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1460                         return -EINVAL;
1461
1462                 /* if we`ve finished resetting, then break out of the loop */
1463                 if (!(portstatus & USB_PORT_STAT_RESET) &&
1464                     (portstatus & USB_PORT_STAT_ENABLE)) {
1465                         if (hub_is_wusb(hub))
1466                                 udev->speed = USB_SPEED_VARIABLE;
1467                         else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1468                                 udev->speed = USB_SPEED_HIGH;
1469                         else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1470                                 udev->speed = USB_SPEED_LOW;
1471                         else
1472                                 udev->speed = USB_SPEED_FULL;
1473                         return 0;
1474                 }
1475
1476                 /* switch to the long delay after two short delay failures */
1477                 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
1478                         delay = HUB_LONG_RESET_TIME;
1479
1480                 dev_dbg (hub->intfdev,
1481                         "port %d not reset yet, waiting %dms\n",
1482                         port1, delay);
1483         }
1484
1485         return -EBUSY;
1486 }
1487
1488 static int hub_port_reset(struct usb_hub *hub, int port1,
1489                                 struct usb_device *udev, unsigned int delay)
1490 {
1491         int i, status;
1492
1493         /* Reset the port */
1494         for (i = 0; i < PORT_RESET_TRIES; i++) {
1495                 status = set_port_feature(hub->hdev,
1496                                 port1, USB_PORT_FEAT_RESET);
1497                 if (status)
1498                         dev_err(hub->intfdev,
1499                                         "cannot reset port %d (err = %d)\n",
1500                                         port1, status);
1501                 else {
1502                         status = hub_port_wait_reset(hub, port1, udev, delay);
1503                         if (status && status != -ENOTCONN)
1504                                 dev_dbg(hub->intfdev,
1505                                                 "port_wait_reset: err = %d\n",
1506                                                 status);
1507                 }
1508
1509                 /* return on disconnect or reset */
1510                 switch (status) {
1511                 case 0:
1512                         /* TRSTRCY = 10 ms; plus some extra */
1513                         msleep(10 + 40);
1514                         /* FALL THROUGH */
1515                 case -ENOTCONN:
1516                 case -ENODEV:
1517                         clear_port_feature(hub->hdev,
1518                                 port1, USB_PORT_FEAT_C_RESET);
1519                         /* FIXME need disconnect() for NOTATTACHED device */
1520                         usb_set_device_state(udev, status
1521                                         ? USB_STATE_NOTATTACHED
1522                                         : USB_STATE_DEFAULT);
1523                         return status;
1524                 }
1525
1526                 dev_dbg (hub->intfdev,
1527                         "port %d not enabled, trying reset again...\n",
1528                         port1);
1529                 delay = HUB_LONG_RESET_TIME;
1530         }
1531
1532         dev_err (hub->intfdev,
1533                 "Cannot enable port %i.  Maybe the USB cable is bad?\n",
1534                 port1);
1535
1536         return status;
1537 }
1538
1539 /*
1540  * Disable a port and mark a logical connnect-change event, so that some
1541  * time later khubd will disconnect() any existing usb_device on the port
1542  * and will re-enumerate if there actually is a device attached.
1543  */
1544 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
1545 {
1546         dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
1547         hub_port_disable(hub, port1, 1);
1548
1549         /* FIXME let caller ask to power down the port:
1550          *  - some devices won't enumerate without a VBUS power cycle
1551          *  - SRP saves power that way
1552          *  - ... new call, TBD ...
1553          * That's easy if this hub can switch power per-port, and
1554          * khubd reactivates the port later (timer, SRP, etc).
1555          * Powerdown must be optional, because of reset/DFU.
1556          */
1557
1558         set_bit(port1, hub->change_bits);
1559         kick_khubd(hub);
1560 }
1561
1562 #ifdef  CONFIG_PM
1563
1564 #ifdef  CONFIG_USB_SUSPEND
1565
1566 /*
1567  * Selective port suspend reduces power; most suspended devices draw
1568  * less than 500 uA.  It's also used in OTG, along with remote wakeup.
1569  * All devices below the suspended port are also suspended.
1570  *
1571  * Devices leave suspend state when the host wakes them up.  Some devices
1572  * also support "remote wakeup", where the device can activate the USB
1573  * tree above them to deliver data, such as a keypress or packet.  In
1574  * some cases, this wakes the USB host.
1575  */
1576 static int hub_port_suspend(struct usb_hub *hub, int port1,
1577                 struct usb_device *udev)
1578 {
1579         int     status;
1580
1581         // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
1582
1583         /* enable remote wakeup when appropriate; this lets the device
1584          * wake up the upstream hub (including maybe the root hub).
1585          *
1586          * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
1587          * we don't explicitly enable it here.
1588          */
1589         if (udev->do_remote_wakeup) {
1590                 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1591                                 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
1592                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1593                                 NULL, 0,
1594                                 USB_CTRL_SET_TIMEOUT);
1595                 if (status)
1596                         dev_dbg(&udev->dev,
1597                                 "won't remote wakeup, status %d\n",
1598                                 status);
1599         }
1600
1601         /* see 7.1.7.6 */
1602         status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
1603         if (status) {
1604                 dev_dbg(hub->intfdev,
1605                         "can't suspend port %d, status %d\n",
1606                         port1, status);
1607                 /* paranoia:  "should not happen" */
1608                 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1609                                 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
1610                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1611                                 NULL, 0,
1612                                 USB_CTRL_SET_TIMEOUT);
1613         } else {
1614                 /* device has up to 10 msec to fully suspend */
1615                 dev_dbg(&udev->dev, "usb %ssuspend\n",
1616                                 udev->auto_pm ? "auto-" : "");
1617                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1618                 msleep(10);
1619         }
1620         return status;
1621 }
1622
1623 /*
1624  * Devices on USB hub ports have only one "suspend" state, corresponding
1625  * to ACPI D2, "may cause the device to lose some context".
1626  * State transitions include:
1627  *
1628  *   - suspend, resume ... when the VBUS power link stays live
1629  *   - suspend, disconnect ... VBUS lost
1630  *
1631  * Once VBUS drop breaks the circuit, the port it's using has to go through
1632  * normal re-enumeration procedures, starting with enabling VBUS power.
1633  * Other than re-initializing the hub (plug/unplug, except for root hubs),
1634  * Linux (2.6) currently has NO mechanisms to initiate that:  no khubd
1635  * timer, no SRP, no requests through sysfs.
1636  *
1637  * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
1638  * the root hub for their bus goes into global suspend ... so we don't
1639  * (falsely) update the device power state to say it suspended.
1640  */
1641 static int __usb_port_suspend (struct usb_device *udev, int port1)
1642 {
1643         int     status = 0;
1644
1645         /* caller owns the udev device lock */
1646         if (port1 < 0)
1647                 return port1;
1648
1649         /* we change the device's upstream USB link,
1650          * but root hubs have no upstream USB link.
1651          */
1652         if (udev->parent)
1653                 status = hub_port_suspend(hdev_to_hub(udev->parent), port1,
1654                                 udev);
1655         else {
1656                 dev_dbg(&udev->dev, "usb %ssuspend\n",
1657                                 udev->auto_pm ? "auto-" : "");
1658                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1659         }
1660         return status;
1661 }
1662
1663 /*
1664  * usb_port_suspend - suspend a usb device's upstream port
1665  * @udev: device that's no longer in active use
1666  * Context: must be able to sleep; device not locked; pm locks held
1667  *
1668  * Suspends a USB device that isn't in active use, conserving power.
1669  * Devices may wake out of a suspend, if anything important happens,
1670  * using the remote wakeup mechanism.  They may also be taken out of
1671  * suspend by the host, using usb_port_resume().  It's also routine
1672  * to disconnect devices while they are suspended.
1673  *
1674  * This only affects the USB hardware for a device; its interfaces
1675  * (and, for hubs, child devices) must already have been suspended.
1676  *
1677  * Suspending OTG devices may trigger HNP, if that's been enabled
1678  * between a pair of dual-role devices.  That will change roles, such
1679  * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
1680  *
1681  * Returns 0 on success, else negative errno.
1682  */
1683 int usb_port_suspend(struct usb_device *udev)
1684 {
1685         return __usb_port_suspend(udev, udev->portnum);
1686 }
1687
1688 /*
1689  * If the USB "suspend" state is in use (rather than "global suspend"),
1690  * many devices will be individually taken out of suspend state using
1691  * special" resume" signaling.  These routines kick in shortly after
1692  * hardware resume signaling is finished, either because of selective
1693  * resume (by host) or remote wakeup (by device) ... now see what changed
1694  * in the tree that's rooted at this device.
1695  */
1696 static int finish_port_resume(struct usb_device *udev)
1697 {
1698         int     status;
1699         u16     devstatus;
1700
1701         /* caller owns the udev device lock */
1702         dev_dbg(&udev->dev, "finish resume\n");
1703
1704         /* usb ch9 identifies four variants of SUSPENDED, based on what
1705          * state the device resumes to.  Linux currently won't see the
1706          * first two on the host side; they'd be inside hub_port_init()
1707          * during many timeouts, but khubd can't suspend until later.
1708          */
1709         usb_set_device_state(udev, udev->actconfig
1710                         ? USB_STATE_CONFIGURED
1711                         : USB_STATE_ADDRESS);
1712
1713         /* 10.5.4.5 says be sure devices in the tree are still there.
1714          * For now let's assume the device didn't go crazy on resume,
1715          * and device drivers will know about any resume quirks.
1716          */
1717         status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
1718         if (status >= 0)
1719                 status = (status == 2 ? 0 : -ENODEV);
1720
1721         if (status)
1722                 dev_dbg(&udev->dev,
1723                         "gone after usb resume? status %d\n",
1724                         status);
1725         else if (udev->actconfig) {
1726                 le16_to_cpus(&devstatus);
1727                 if ((devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP))
1728                                 && udev->parent) {
1729                         status = usb_control_msg(udev,
1730                                         usb_sndctrlpipe(udev, 0),
1731                                         USB_REQ_CLEAR_FEATURE,
1732                                                 USB_RECIP_DEVICE,
1733                                         USB_DEVICE_REMOTE_WAKEUP, 0,
1734                                         NULL, 0,
1735                                         USB_CTRL_SET_TIMEOUT);
1736                         if (status)
1737                                 dev_dbg(&udev->dev, "disable remote "
1738                                         "wakeup, status %d\n", status);
1739                 }
1740                 status = 0;
1741
1742         } else if (udev->devnum <= 0) {
1743                 dev_dbg(&udev->dev, "bogus resume!\n");
1744                 status = -EINVAL;
1745         }
1746         return status;
1747 }
1748
1749 static int
1750 hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
1751 {
1752         int     status;
1753         u16     portchange, portstatus;
1754
1755         /* Skip the initial Clear-Suspend step for a remote wakeup */
1756         status = hub_port_status(hub, port1, &portstatus, &portchange);
1757         if (status == 0 && !(portstatus & USB_PORT_STAT_SUSPEND))
1758                 goto SuspendCleared;
1759
1760         // dev_dbg(hub->intfdev, "resume port %d\n", port1);
1761
1762         set_bit(port1, hub->busy_bits);
1763
1764         /* see 7.1.7.7; affects power usage, but not budgeting */
1765         status = clear_port_feature(hub->hdev,
1766                         port1, USB_PORT_FEAT_SUSPEND);
1767         if (status) {
1768                 dev_dbg(hub->intfdev,
1769                         "can't resume port %d, status %d\n",
1770                         port1, status);
1771         } else {
1772                 /* drive resume for at least 20 msec */
1773                 if (udev)
1774                         dev_dbg(&udev->dev, "usb %sresume\n",
1775                                         udev->auto_pm ? "auto-" : "");
1776                 msleep(25);
1777
1778 #define LIVE_FLAGS      ( USB_PORT_STAT_POWER \
1779                         | USB_PORT_STAT_ENABLE \
1780                         | USB_PORT_STAT_CONNECTION)
1781
1782                 /* Virtual root hubs can trigger on GET_PORT_STATUS to
1783                  * stop resume signaling.  Then finish the resume
1784                  * sequence.
1785                  */
1786                 status = hub_port_status(hub, port1, &portstatus, &portchange);
1787 SuspendCleared:
1788                 if (status < 0
1789                                 || (portstatus & LIVE_FLAGS) != LIVE_FLAGS
1790                                 || (portstatus & USB_PORT_STAT_SUSPEND) != 0
1791                                 ) {
1792                         dev_dbg(hub->intfdev,
1793                                 "port %d status %04x.%04x after resume, %d\n",
1794                                 port1, portchange, portstatus, status);
1795                         if (status >= 0)
1796                                 status = -ENODEV;
1797                 } else {
1798                         if (portchange & USB_PORT_STAT_C_SUSPEND)
1799                                 clear_port_feature(hub->hdev, port1,
1800                                                 USB_PORT_FEAT_C_SUSPEND);
1801                         /* TRSMRCY = 10 msec */
1802                         msleep(10);
1803                         if (udev)
1804                                 status = finish_port_resume(udev);
1805                 }
1806         }
1807         if (status < 0)
1808                 hub_port_logical_disconnect(hub, port1);
1809
1810         clear_bit(port1, hub->busy_bits);
1811         if (!hub->hdev->parent && !hub->busy_bits[0])
1812                 usb_enable_root_hub_irq(hub->hdev->bus);
1813
1814         return status;
1815 }
1816
1817 /*
1818  * usb_port_resume - re-activate a suspended usb device's upstream port
1819  * @udev: device to re-activate
1820  * Context: must be able to sleep; device not locked; pm locks held
1821  *
1822  * This will re-activate the suspended device, increasing power usage
1823  * while letting drivers communicate again with its endpoints.
1824  * USB resume explicitly guarantees that the power session between
1825  * the host and the device is the same as it was when the device
1826  * suspended.
1827  *
1828  * Returns 0 on success, else negative errno.
1829  */
1830 int usb_port_resume(struct usb_device *udev)
1831 {
1832         int     status;
1833
1834         /* we change the device's upstream USB link,
1835          * but root hubs have no upstream USB link.
1836          */
1837         if (udev->parent) {
1838                 // NOTE this fails if parent is also suspended...
1839                 status = hub_port_resume(hdev_to_hub(udev->parent),
1840                                 udev->portnum, udev);
1841         } else {
1842                 dev_dbg(&udev->dev, "usb %sresume\n",
1843                                 udev->auto_pm ? "auto-" : "");
1844                 status = finish_port_resume(udev);
1845         }
1846         if (status < 0)
1847                 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
1848         return status;
1849 }
1850
1851 static int remote_wakeup(struct usb_device *udev)
1852 {
1853         int     status = 0;
1854
1855         usb_lock_device(udev);
1856         if (udev->state == USB_STATE_SUSPENDED) {
1857                 dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
1858                 status = usb_autoresume_device(udev);
1859
1860                 /* Give the interface drivers a chance to do something,
1861                  * then autosuspend the device again. */
1862                 if (status == 0)
1863                         usb_autosuspend_device(udev);
1864         }
1865         usb_unlock_device(udev);
1866         return status;
1867 }
1868
1869 #else   /* CONFIG_USB_SUSPEND */
1870
1871 /* When CONFIG_USB_SUSPEND isn't set, we never suspend or resume any ports. */
1872
1873 int usb_port_suspend(struct usb_device *udev)
1874 {
1875         return 0;
1876 }
1877
1878 static inline int
1879 finish_port_resume(struct usb_device *udev)
1880 {
1881         return 0;
1882 }
1883
1884 static inline int
1885 hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
1886 {
1887         return 0;
1888 }
1889
1890 int usb_port_resume(struct usb_device *udev)
1891 {
1892         return 0;
1893 }
1894
1895 static inline int remote_wakeup(struct usb_device *udev)
1896 {
1897         return 0;
1898 }
1899
1900 #endif
1901
1902 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
1903 {
1904         struct usb_hub          *hub = usb_get_intfdata (intf);
1905         struct usb_device       *hdev = hub->hdev;
1906         unsigned                port1;
1907
1908         /* fail if children aren't already suspended */
1909         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1910                 struct usb_device       *udev;
1911
1912                 udev = hdev->children [port1-1];
1913                 if (udev && msg.event == PM_EVENT_SUSPEND &&
1914 #ifdef  CONFIG_USB_SUSPEND
1915                                 udev->state != USB_STATE_SUSPENDED
1916 #else
1917                                 udev->dev.power.power_state.event
1918                                         == PM_EVENT_ON
1919 #endif
1920                                 ) {
1921                         if (!hdev->auto_pm)
1922                                 dev_dbg(&intf->dev, "port %d nyet suspended\n",
1923                                                 port1);
1924                         return -EBUSY;
1925                 }
1926         }
1927
1928         dev_dbg(&intf->dev, "%s\n", __FUNCTION__);
1929
1930         /* "global suspend" of the downstream HC-to-USB interface */
1931         if (!hdev->parent) {
1932                 struct usb_bus  *bus = hdev->bus;
1933                 if (bus) {
1934                         int     status = hcd_bus_suspend (bus);
1935
1936                         if (status != 0) {
1937                                 dev_dbg(&hdev->dev, "'global' suspend %d\n",
1938                                         status);
1939                                 return status;
1940                         }
1941                 } else
1942                         return -EOPNOTSUPP;
1943         }
1944
1945         /* stop khubd and related activity */
1946         hub_quiesce(hub);
1947         return 0;
1948 }
1949
1950 static int hub_resume(struct usb_interface *intf)
1951 {
1952         struct usb_hub          *hub = usb_get_intfdata (intf);
1953         struct usb_device       *hdev = hub->hdev;
1954         int                     status;
1955
1956         dev_dbg(&intf->dev, "%s\n", __FUNCTION__);
1957
1958         /* "global resume" of the downstream HC-to-USB interface */
1959         if (!hdev->parent) {
1960                 struct usb_bus  *bus = hdev->bus;
1961                 if (bus) {
1962                         status = hcd_bus_resume (bus);
1963                         if (status) {
1964                                 dev_dbg(&intf->dev, "'global' resume %d\n",
1965                                         status);
1966                                 return status;
1967                         }
1968                 } else
1969                         return -EOPNOTSUPP;
1970                 if (status == 0) {
1971                         /* TRSMRCY = 10 msec */
1972                         msleep(10);
1973                 }
1974         }
1975
1976         /* tell khubd to look for changes on this hub */
1977         hub_activate(hub);
1978         return 0;
1979 }
1980
1981 #else   /* CONFIG_PM */
1982
1983 static inline int remote_wakeup(struct usb_device *udev)
1984 {
1985         return 0;
1986 }
1987
1988 #define hub_suspend NULL
1989 #define hub_resume NULL
1990 #endif
1991
1992 void usb_resume_root_hub(struct usb_device *hdev)
1993 {
1994         struct usb_hub *hub = hdev_to_hub(hdev);
1995
1996         kick_khubd(hub);
1997 }
1998
1999
2000 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
2001  *
2002  * Between connect detection and reset signaling there must be a delay
2003  * of 100ms at least for debounce and power-settling.  The corresponding
2004  * timer shall restart whenever the downstream port detects a disconnect.
2005  * 
2006  * Apparently there are some bluetooth and irda-dongles and a number of
2007  * low-speed devices for which this debounce period may last over a second.
2008  * Not covered by the spec - but easy to deal with.
2009  *
2010  * This implementation uses a 1500ms total debounce timeout; if the
2011  * connection isn't stable by then it returns -ETIMEDOUT.  It checks
2012  * every 25ms for transient disconnects.  When the port status has been
2013  * unchanged for 100ms it returns the port status.
2014  */
2015
2016 #define HUB_DEBOUNCE_TIMEOUT    1500
2017 #define HUB_DEBOUNCE_STEP         25
2018 #define HUB_DEBOUNCE_STABLE      100
2019
2020 static int hub_port_debounce(struct usb_hub *hub, int port1)
2021 {
2022         int ret;
2023         int total_time, stable_time = 0;
2024         u16 portchange, portstatus;
2025         unsigned connection = 0xffff;
2026
2027         for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
2028                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2029                 if (ret < 0)
2030                         return ret;
2031
2032                 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
2033                      (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2034                         stable_time += HUB_DEBOUNCE_STEP;
2035                         if (stable_time >= HUB_DEBOUNCE_STABLE)
2036                                 break;
2037                 } else {
2038                         stable_time = 0;
2039                         connection = portstatus & USB_PORT_STAT_CONNECTION;
2040                 }
2041
2042                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2043                         clear_port_feature(hub->hdev, port1,
2044                                         USB_PORT_FEAT_C_CONNECTION);
2045                 }
2046
2047                 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2048                         break;
2049                 msleep(HUB_DEBOUNCE_STEP);
2050         }
2051
2052         dev_dbg (hub->intfdev,
2053                 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2054                 port1, total_time, stable_time, portstatus);
2055
2056         if (stable_time < HUB_DEBOUNCE_STABLE)
2057                 return -ETIMEDOUT;
2058         return portstatus;
2059 }
2060
2061 static void ep0_reinit(struct usb_device *udev)
2062 {
2063         usb_disable_endpoint(udev, 0 + USB_DIR_IN);
2064         usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
2065         udev->ep_in[0] = udev->ep_out[0] = &udev->ep0;
2066 }
2067
2068 #define usb_sndaddr0pipe()      (PIPE_CONTROL << 30)
2069 #define usb_rcvaddr0pipe()      ((PIPE_CONTROL << 30) | USB_DIR_IN)
2070
2071 static int hub_set_address(struct usb_device *udev)
2072 {
2073         int retval;
2074
2075         if (udev->devnum == 0)
2076                 return -EINVAL;
2077         if (udev->state == USB_STATE_ADDRESS)
2078                 return 0;
2079         if (udev->state != USB_STATE_DEFAULT)
2080                 return -EINVAL;
2081         retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2082                 USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
2083                 NULL, 0, USB_CTRL_SET_TIMEOUT);
2084         if (retval == 0) {
2085                 usb_set_device_state(udev, USB_STATE_ADDRESS);
2086                 ep0_reinit(udev);
2087         }
2088         return retval;
2089 }
2090
2091 /* Reset device, (re)assign address, get device descriptor.
2092  * Device connection must be stable, no more debouncing needed.
2093  * Returns device in USB_STATE_ADDRESS, except on error.
2094  *
2095  * If this is called for an already-existing device (as part of
2096  * usb_reset_device), the caller must own the device lock.  For a
2097  * newly detected device that is not accessible through any global
2098  * pointers, it's not necessary to lock the device.
2099  */
2100 static int
2101 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2102                 int retry_counter)
2103 {
2104         static DEFINE_MUTEX(usb_address0_mutex);
2105
2106         struct usb_device       *hdev = hub->hdev;
2107         int                     i, j, retval;
2108         unsigned                delay = HUB_SHORT_RESET_TIME;
2109         enum usb_device_speed   oldspeed = udev->speed;
2110         char                    *speed, *type;
2111
2112         /* root hub ports have a slightly longer reset period
2113          * (from USB 2.0 spec, section 7.1.7.5)
2114          */
2115         if (!hdev->parent) {
2116                 delay = HUB_ROOT_RESET_TIME;
2117                 if (port1 == hdev->bus->otg_port)
2118                         hdev->bus->b_hnp_enable = 0;
2119         }
2120
2121         /* Some low speed devices have problems with the quick delay, so */
2122         /*  be a bit pessimistic with those devices. RHbug #23670 */
2123         if (oldspeed == USB_SPEED_LOW)
2124                 delay = HUB_LONG_RESET_TIME;
2125
2126         mutex_lock(&usb_address0_mutex);
2127
2128         /* Reset the device; full speed may morph to high speed */
2129         retval = hub_port_reset(hub, port1, udev, delay);
2130         if (retval < 0)         /* error or disconnect */
2131                 goto fail;
2132                                 /* success, speed is known */
2133         retval = -ENODEV;
2134
2135         if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2136                 dev_dbg(&udev->dev, "device reset changed speed!\n");
2137                 goto fail;
2138         }
2139         oldspeed = udev->speed;
2140   
2141         /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2142          * it's fixed size except for full speed devices.
2143          * For Wireless USB devices, ep0 max packet is always 512 (tho
2144          * reported as 0xff in the device descriptor). WUSB1.0[4.8.1].
2145          */
2146         switch (udev->speed) {
2147         case USB_SPEED_VARIABLE:        /* fixed at 512 */
2148                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(512);
2149                 break;
2150         case USB_SPEED_HIGH:            /* fixed at 64 */
2151                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2152                 break;
2153         case USB_SPEED_FULL:            /* 8, 16, 32, or 64 */
2154                 /* to determine the ep0 maxpacket size, try to read
2155                  * the device descriptor to get bMaxPacketSize0 and
2156                  * then correct our initial guess.
2157                  */
2158                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2159                 break;
2160         case USB_SPEED_LOW:             /* fixed at 8 */
2161                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
2162                 break;
2163         default:
2164                 goto fail;
2165         }
2166  
2167         type = "";
2168         switch (udev->speed) {
2169         case USB_SPEED_LOW:     speed = "low";  break;
2170         case USB_SPEED_FULL:    speed = "full"; break;
2171         case USB_SPEED_HIGH:    speed = "high"; break;
2172         case USB_SPEED_VARIABLE:
2173                                 speed = "variable";
2174                                 type = "Wireless ";
2175                                 break;
2176         default:                speed = "?";    break;
2177         }
2178         dev_info (&udev->dev,
2179                   "%s %s speed %sUSB device using %s and address %d\n",
2180                   (udev->config) ? "reset" : "new", speed, type,
2181                   udev->bus->controller->driver->name, udev->devnum);
2182
2183         /* Set up TT records, if needed  */
2184         if (hdev->tt) {
2185                 udev->tt = hdev->tt;
2186                 udev->ttport = hdev->ttport;
2187         } else if (udev->speed != USB_SPEED_HIGH
2188                         && hdev->speed == USB_SPEED_HIGH) {
2189                 udev->tt = &hub->tt;
2190                 udev->ttport = port1;
2191         }
2192  
2193         /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2194          * Because device hardware and firmware is sometimes buggy in
2195          * this area, and this is how Linux has done it for ages.
2196          * Change it cautiously.
2197          *
2198          * NOTE:  If USE_NEW_SCHEME() is true we will start by issuing
2199          * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
2200          * so it may help with some non-standards-compliant devices.
2201          * Otherwise we start with SET_ADDRESS and then try to read the
2202          * first 8 bytes of the device descriptor to get the ep0 maxpacket
2203          * value.
2204          */
2205         for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2206                 if (USE_NEW_SCHEME(retry_counter)) {
2207                         struct usb_device_descriptor *buf;
2208                         int r = 0;
2209
2210 #define GET_DESCRIPTOR_BUFSIZE  64
2211                         buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2212                         if (!buf) {
2213                                 retval = -ENOMEM;
2214                                 continue;
2215                         }
2216
2217                         /* Use a short timeout the first time through,
2218                          * so that recalcitrant full-speed devices with
2219                          * 8- or 16-byte ep0-maxpackets won't slow things
2220                          * down tremendously by NAKing the unexpectedly
2221                          * early status stage.  Also, retry on all errors;
2222                          * some devices are flakey.
2223                          * 255 is for WUSB devices, we actually need to use 512.
2224                          * WUSB1.0[4.8.1].
2225                          */
2226                         for (j = 0; j < 3; ++j) {
2227                                 buf->bMaxPacketSize0 = 0;
2228                                 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2229                                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2230                                         USB_DT_DEVICE << 8, 0,
2231                                         buf, GET_DESCRIPTOR_BUFSIZE,
2232                                         (i ? USB_CTRL_GET_TIMEOUT : 1000));
2233                                 switch (buf->bMaxPacketSize0) {
2234                                 case 8: case 16: case 32: case 64: case 255:
2235                                         if (buf->bDescriptorType ==
2236                                                         USB_DT_DEVICE) {
2237                                                 r = 0;
2238                                                 break;
2239                                         }
2240                                         /* FALL THROUGH */
2241                                 default:
2242                                         if (r == 0)
2243                                                 r = -EPROTO;
2244                                         break;
2245                                 }
2246                                 if (r == 0)
2247                                         break;
2248                         }
2249                         udev->descriptor.bMaxPacketSize0 =
2250                                         buf->bMaxPacketSize0;
2251                         kfree(buf);
2252
2253                         retval = hub_port_reset(hub, port1, udev, delay);
2254                         if (retval < 0)         /* error or disconnect */
2255                                 goto fail;
2256                         if (oldspeed != udev->speed) {
2257                                 dev_dbg(&udev->dev,
2258                                         "device reset changed speed!\n");
2259                                 retval = -ENODEV;
2260                                 goto fail;
2261                         }
2262                         if (r) {
2263                                 dev_err(&udev->dev, "device descriptor "
2264                                                 "read/%s, error %d\n",
2265                                                 "64", r);
2266                                 retval = -EMSGSIZE;
2267                                 continue;
2268                         }
2269 #undef GET_DESCRIPTOR_BUFSIZE
2270                 }
2271
2272                 for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2273                         retval = hub_set_address(udev);
2274                         if (retval >= 0)
2275                                 break;
2276                         msleep(200);
2277                 }
2278                 if (retval < 0) {
2279                         dev_err(&udev->dev,
2280                                 "device not accepting address %d, error %d\n",
2281                                 udev->devnum, retval);
2282                         goto fail;
2283                 }
2284  
2285                 /* cope with hardware quirkiness:
2286                  *  - let SET_ADDRESS settle, some device hardware wants it
2287                  *  - read ep0 maxpacket even for high and low speed,
2288                  */
2289                 msleep(10);
2290                 if (USE_NEW_SCHEME(retry_counter))
2291                         break;
2292
2293                 retval = usb_get_device_descriptor(udev, 8);
2294                 if (retval < 8) {
2295                         dev_err(&udev->dev, "device descriptor "
2296                                         "read/%s, error %d\n",
2297                                         "8", retval);
2298                         if (retval >= 0)
2299                                 retval = -EMSGSIZE;
2300                 } else {
2301                         retval = 0;
2302                         break;
2303                 }
2304         }
2305         if (retval)
2306                 goto fail;
2307
2308         i = udev->descriptor.bMaxPacketSize0 == 0xff?
2309             512 : udev->descriptor.bMaxPacketSize0;
2310         if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2311                 if (udev->speed != USB_SPEED_FULL ||
2312                                 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2313                         dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
2314                         retval = -EMSGSIZE;
2315                         goto fail;
2316                 }
2317                 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2318                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2319                 ep0_reinit(udev);
2320         }
2321   
2322         retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2323         if (retval < (signed)sizeof(udev->descriptor)) {
2324                 dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
2325                         "all", retval);
2326                 if (retval >= 0)
2327                         retval = -ENOMSG;
2328                 goto fail;
2329         }
2330
2331         retval = 0;
2332
2333 fail:
2334         if (retval)
2335                 hub_port_disable(hub, port1, 0);
2336         mutex_unlock(&usb_address0_mutex);
2337         return retval;
2338 }
2339
2340 static void
2341 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2342 {
2343         struct usb_qualifier_descriptor *qual;
2344         int                             status;
2345
2346         qual = kmalloc (sizeof *qual, GFP_KERNEL);
2347         if (qual == NULL)
2348                 return;
2349
2350         status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2351                         qual, sizeof *qual);
2352         if (status == sizeof *qual) {
2353                 dev_info(&udev->dev, "not running at top speed; "
2354                         "connect to a high speed hub\n");
2355                 /* hub LEDs are probably harder to miss than syslog */
2356                 if (hub->has_indicators) {
2357                         hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2358                         schedule_delayed_work (&hub->leds, 0);
2359                 }
2360         }
2361         kfree(qual);
2362 }
2363
2364 static unsigned
2365 hub_power_remaining (struct usb_hub *hub)
2366 {
2367         struct usb_device *hdev = hub->hdev;
2368         int remaining;
2369         int port1;
2370
2371         if (!hub->limited_power)
2372                 return 0;
2373
2374         remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
2375         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
2376                 struct usb_device       *udev = hdev->children[port1 - 1];
2377                 int                     delta;
2378
2379                 if (!udev)
2380                         continue;
2381
2382                 /* Unconfigured devices may not use more than 100mA,
2383                  * or 8mA for OTG ports */
2384                 if (udev->actconfig)
2385                         delta = udev->actconfig->desc.bMaxPower * 2;
2386                 else if (port1 != udev->bus->otg_port || hdev->parent)
2387                         delta = 100;
2388                 else
2389                         delta = 8;
2390                 if (delta > hub->mA_per_port)
2391                         dev_warn(&udev->dev, "%dmA is over %umA budget "
2392                                         "for port %d!\n",
2393                                         delta, hub->mA_per_port, port1);
2394                 remaining -= delta;
2395         }
2396         if (remaining < 0) {
2397                 dev_warn(hub->intfdev, "%dmA over power budget!\n",
2398                         - remaining);
2399                 remaining = 0;
2400         }
2401         return remaining;
2402 }
2403
2404 /* Handle physical or logical connection change events.
2405  * This routine is called when:
2406  *      a port connection-change occurs;
2407  *      a port enable-change occurs (often caused by EMI);
2408  *      usb_reset_device() encounters changed descriptors (as from
2409  *              a firmware download)
2410  * caller already locked the hub
2411  */
2412 static void hub_port_connect_change(struct usb_hub *hub, int port1,
2413                                         u16 portstatus, u16 portchange)
2414 {
2415         struct usb_device *hdev = hub->hdev;
2416         struct device *hub_dev = hub->intfdev;
2417         u16 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
2418         int status, i;
2419  
2420         dev_dbg (hub_dev,
2421                 "port %d, status %04x, change %04x, %s\n",
2422                 port1, portstatus, portchange, portspeed (portstatus));
2423
2424         if (hub->has_indicators) {
2425                 set_port_led(hub, port1, HUB_LED_AUTO);
2426                 hub->indicator[port1-1] = INDICATOR_AUTO;
2427         }
2428  
2429         /* Disconnect any existing devices under this port */
2430         if (hdev->children[port1-1])
2431                 usb_disconnect(&hdev->children[port1-1]);
2432         clear_bit(port1, hub->change_bits);
2433
2434 #ifdef  CONFIG_USB_OTG
2435         /* during HNP, don't repeat the debounce */
2436         if (hdev->bus->is_b_host)
2437                 portchange &= ~USB_PORT_STAT_C_CONNECTION;
2438 #endif
2439
2440         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2441                 status = hub_port_debounce(hub, port1);
2442                 if (status < 0) {
2443                         dev_err (hub_dev,
2444                                 "connect-debounce failed, port %d disabled\n",
2445                                 port1);
2446                         goto done;
2447                 }
2448                 portstatus = status;
2449         }
2450
2451         /* Return now if nothing is connected */
2452         if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2453
2454                 /* maybe switch power back on (e.g. root hub was reset) */
2455                 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2
2456                                 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
2457                         set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
2458  
2459                 if (portstatus & USB_PORT_STAT_ENABLE)
2460                         goto done;
2461                 return;
2462         }
2463
2464 #ifdef  CONFIG_USB_SUSPEND
2465         /* If something is connected, but the port is suspended, wake it up. */
2466         if (portstatus & USB_PORT_STAT_SUSPEND) {
2467                 status = hub_port_resume(hub, port1, NULL);
2468                 if (status < 0) {
2469                         dev_dbg(hub_dev,
2470                                 "can't clear suspend on port %d; %d\n",
2471                                 port1, status);
2472                         goto done;
2473                 }
2474         }
2475 #endif
2476
2477         for (i = 0; i < SET_CONFIG_TRIES; i++) {
2478                 struct usb_device *udev;
2479
2480                 /* reallocate for each attempt, since references
2481                  * to the previous one can escape in various ways
2482                  */
2483                 udev = usb_alloc_dev(hdev, hdev->bus, port1);
2484                 if (!udev) {
2485                         dev_err (hub_dev,
2486                                 "couldn't allocate port %d usb_device\n",
2487                                 port1);
2488                         goto done;
2489                 }
2490
2491                 usb_set_device_state(udev, USB_STATE_POWERED);
2492                 udev->speed = USB_SPEED_UNKNOWN;
2493                 udev->bus_mA = hub->mA_per_port;
2494                 udev->level = hdev->level + 1;
2495
2496                 /* set the address */
2497                 choose_address(udev);
2498                 if (udev->devnum <= 0) {
2499                         status = -ENOTCONN;     /* Don't retry */
2500                         goto loop;
2501                 }
2502
2503                 /* reset and get descriptor */
2504                 status = hub_port_init(hub, udev, port1, i);
2505                 if (status < 0)
2506                         goto loop;
2507
2508                 /* consecutive bus-powered hubs aren't reliable; they can
2509                  * violate the voltage drop budget.  if the new child has
2510                  * a "powered" LED, users should notice we didn't enable it
2511                  * (without reading syslog), even without per-port LEDs
2512                  * on the parent.
2513                  */
2514                 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
2515                                 && udev->bus_mA <= 100) {
2516                         u16     devstat;
2517
2518                         status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
2519                                         &devstat);
2520                         if (status < 2) {
2521                                 dev_dbg(&udev->dev, "get status %d ?\n", status);
2522                                 goto loop_disable;
2523                         }
2524                         le16_to_cpus(&devstat);
2525                         if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
2526                                 dev_err(&udev->dev,
2527                                         "can't connect bus-powered hub "
2528                                         "to this port\n");
2529                                 if (hub->has_indicators) {
2530                                         hub->indicator[port1-1] =
2531                                                 INDICATOR_AMBER_BLINK;
2532                                         schedule_delayed_work (&hub->leds, 0);
2533                                 }
2534                                 status = -ENOTCONN;     /* Don't retry */
2535                                 goto loop_disable;
2536                         }
2537                 }
2538  
2539                 /* check for devices running slower than they could */
2540                 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
2541                                 && udev->speed == USB_SPEED_FULL
2542                                 && highspeed_hubs != 0)
2543                         check_highspeed (hub, udev, port1);
2544
2545                 /* Store the parent's children[] pointer.  At this point
2546                  * udev becomes globally accessible, although presumably
2547                  * no one will look at it until hdev is unlocked.
2548                  */
2549                 status = 0;
2550
2551                 /* We mustn't add new devices if the parent hub has
2552                  * been disconnected; we would race with the
2553                  * recursively_mark_NOTATTACHED() routine.
2554                  */
2555                 spin_lock_irq(&device_state_lock);
2556                 if (hdev->state == USB_STATE_NOTATTACHED)
2557                         status = -ENOTCONN;
2558                 else
2559                         hdev->children[port1-1] = udev;
2560                 spin_unlock_irq(&device_state_lock);
2561
2562                 /* Run it through the hoops (find a driver, etc) */
2563                 if (!status) {
2564                         status = usb_new_device(udev);
2565                         if (status) {
2566                                 spin_lock_irq(&device_state_lock);
2567                                 hdev->children[port1-1] = NULL;
2568                                 spin_unlock_irq(&device_state_lock);
2569                         }
2570                 }
2571
2572                 if (status)
2573                         goto loop_disable;
2574
2575                 status = hub_power_remaining(hub);
2576                 if (status)
2577                         dev_dbg(hub_dev, "%dmA power budget left\n", status);
2578
2579                 return;
2580
2581 loop_disable:
2582                 hub_port_disable(hub, port1, 1);
2583 loop:
2584                 ep0_reinit(udev);
2585                 release_address(udev);
2586                 usb_put_dev(udev);
2587                 if (status == -ENOTCONN)
2588                         break;
2589         }
2590  
2591 done:
2592         hub_port_disable(hub, port1, 1);
2593 }
2594
2595 static void hub_events(void)
2596 {
2597         struct list_head *tmp;
2598         struct usb_device *hdev;
2599         struct usb_interface *intf;
2600         struct usb_hub *hub;
2601         struct device *hub_dev;
2602         u16 hubstatus;
2603         u16 hubchange;
2604         u16 portstatus;
2605         u16 portchange;
2606         int i, ret;
2607         int connect_change;
2608
2609         /*
2610          *  We restart the list every time to avoid a deadlock with
2611          * deleting hubs downstream from this one. This should be
2612          * safe since we delete the hub from the event list.
2613          * Not the most efficient, but avoids deadlocks.
2614          */
2615         while (1) {
2616
2617                 /* Grab the first entry at the beginning of the list */
2618                 spin_lock_irq(&hub_event_lock);
2619                 if (list_empty(&hub_event_list)) {
2620                         spin_unlock_irq(&hub_event_lock);
2621                         break;
2622                 }
2623
2624                 tmp = hub_event_list.next;
2625                 list_del_init(tmp);
2626
2627                 hub = list_entry(tmp, struct usb_hub, event_list);
2628                 hdev = hub->hdev;
2629                 intf = to_usb_interface(hub->intfdev);
2630                 hub_dev = &intf->dev;
2631
2632                 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
2633                                 hdev->state, hub->descriptor
2634                                         ? hub->descriptor->bNbrPorts
2635                                         : 0,
2636                                 /* NOTE: expects max 15 ports... */
2637                                 (u16) hub->change_bits[0],
2638                                 (u16) hub->event_bits[0]);
2639
2640                 usb_get_intf(intf);
2641                 spin_unlock_irq(&hub_event_lock);
2642
2643                 /* Lock the device, then check to see if we were
2644                  * disconnected while waiting for the lock to succeed. */
2645                 if (locktree(hdev) < 0) {
2646                         usb_put_intf(intf);
2647                         continue;
2648                 }
2649                 if (hub != usb_get_intfdata(intf))
2650                         goto loop;
2651
2652                 /* If the hub has died, clean up after it */
2653                 if (hdev->state == USB_STATE_NOTATTACHED) {
2654                         hub->error = -ENODEV;
2655                         hub_pre_reset(intf);
2656                         goto loop;
2657                 }
2658
2659                 /* Autoresume */
2660                 ret = usb_autopm_get_interface(intf);
2661                 if (ret) {
2662                         dev_dbg(hub_dev, "Can't autoresume: %d\n", ret);
2663                         goto loop;
2664                 }
2665
2666                 /* If this is an inactive hub, do nothing */
2667                 if (hub->quiescing)
2668                         goto loop_autopm;
2669
2670                 if (hub->error) {
2671                         dev_dbg (hub_dev, "resetting for error %d\n",
2672                                 hub->error);
2673
2674                         ret = usb_reset_composite_device(hdev, intf);
2675                         if (ret) {
2676                                 dev_dbg (hub_dev,
2677                                         "error resetting hub: %d\n", ret);
2678                                 goto loop_autopm;
2679                         }
2680
2681                         hub->nerrors = 0;
2682                         hub->error = 0;
2683                 }
2684
2685                 /* deal with port status changes */
2686                 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
2687                         if (test_bit(i, hub->busy_bits))
2688                                 continue;
2689                         connect_change = test_bit(i, hub->change_bits);
2690                         if (!test_and_clear_bit(i, hub->event_bits) &&
2691                                         !connect_change && !hub->activating)
2692                                 continue;
2693
2694                         ret = hub_port_status(hub, i,
2695                                         &portstatus, &portchange);
2696                         if (ret < 0)
2697                                 continue;
2698
2699                         if (hub->activating && !hdev->children[i-1] &&
2700                                         (portstatus &
2701                                                 USB_PORT_STAT_CONNECTION))
2702                                 connect_change = 1;
2703
2704                         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2705                                 clear_port_feature(hdev, i,
2706                                         USB_PORT_FEAT_C_CONNECTION);
2707                                 connect_change = 1;
2708                         }
2709
2710                         if (portchange & USB_PORT_STAT_C_ENABLE) {
2711                                 if (!connect_change)
2712                                         dev_dbg (hub_dev,
2713                                                 "port %d enable change, "
2714                                                 "status %08x\n",
2715                                                 i, portstatus);
2716                                 clear_port_feature(hdev, i,
2717                                         USB_PORT_FEAT_C_ENABLE);
2718
2719                                 /*
2720                                  * EM interference sometimes causes badly
2721                                  * shielded USB devices to be shutdown by
2722                                  * the hub, this hack enables them again.
2723                                  * Works at least with mouse driver. 
2724                                  */
2725                                 if (!(portstatus & USB_PORT_STAT_ENABLE)
2726                                     && !connect_change
2727                                     && hdev->children[i-1]) {
2728                                         dev_err (hub_dev,
2729                                             "port %i "
2730                                             "disabled by hub (EMI?), "
2731                                             "re-enabling...\n",
2732                                                 i);
2733                                         connect_change = 1;
2734                                 }
2735                         }
2736
2737                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
2738                                 clear_port_feature(hdev, i,
2739                                         USB_PORT_FEAT_C_SUSPEND);
2740                                 if (hdev->children[i-1]) {
2741                                         ret = remote_wakeup(hdev->
2742                                                         children[i-1]);
2743                                         if (ret < 0)
2744                                                 connect_change = 1;
2745                                 } else {
2746                                         ret = -ENODEV;
2747                                         hub_port_disable(hub, i, 1);
2748                                 }
2749                                 dev_dbg (hub_dev,
2750                                         "resume on port %d, status %d\n",
2751                                         i, ret);
2752                         }
2753                         
2754                         if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
2755                                 dev_err (hub_dev,
2756                                         "over-current change on port %d\n",
2757                                         i);
2758                                 clear_port_feature(hdev, i,
2759                                         USB_PORT_FEAT_C_OVER_CURRENT);
2760                                 hub_power_on(hub);
2761                         }
2762
2763                         if (portchange & USB_PORT_STAT_C_RESET) {
2764                                 dev_dbg (hub_dev,
2765                                         "reset change on port %d\n",
2766                                         i);
2767                                 clear_port_feature(hdev, i,
2768                                         USB_PORT_FEAT_C_RESET);
2769                         }
2770
2771                         if (connect_change)
2772                                 hub_port_connect_change(hub, i,
2773                                                 portstatus, portchange);
2774                 } /* end for i */
2775
2776                 /* deal with hub status changes */
2777                 if (test_and_clear_bit(0, hub->event_bits) == 0)
2778                         ;       /* do nothing */
2779                 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
2780                         dev_err (hub_dev, "get_hub_status failed\n");
2781                 else {
2782                         if (hubchange & HUB_CHANGE_LOCAL_POWER) {
2783                                 dev_dbg (hub_dev, "power change\n");
2784                                 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
2785                                 if (hubstatus & HUB_STATUS_LOCAL_POWER)
2786                                         /* FIXME: Is this always true? */
2787                                         hub->limited_power = 0;
2788                                 else
2789                                         hub->limited_power = 1;
2790                         }
2791                         if (hubchange & HUB_CHANGE_OVERCURRENT) {
2792                                 dev_dbg (hub_dev, "overcurrent change\n");
2793                                 msleep(500);    /* Cool down */
2794                                 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
2795                                 hub_power_on(hub);
2796                         }
2797                 }
2798
2799                 hub->activating = 0;
2800
2801                 /* If this is a root hub, tell the HCD it's okay to
2802                  * re-enable port-change interrupts now. */
2803                 if (!hdev->parent && !hub->busy_bits[0])
2804                         usb_enable_root_hub_irq(hdev->bus);
2805
2806 loop_autopm:
2807                 /* Allow autosuspend if we're not going to run again */
2808                 if (list_empty(&hub->event_list))
2809                         usb_autopm_enable(intf);
2810 loop:
2811                 usb_unlock_device(hdev);
2812                 usb_put_intf(intf);
2813
2814         } /* end while (1) */
2815 }
2816
2817 static int hub_thread(void *__unused)
2818 {
2819         do {
2820                 hub_events();
2821                 wait_event_interruptible(khubd_wait,
2822                                 !list_empty(&hub_event_list) ||
2823                                 kthread_should_stop());
2824                 try_to_freeze();
2825         } while (!kthread_should_stop() || !list_empty(&hub_event_list));
2826
2827         pr_debug("%s: khubd exiting\n", usbcore_name);
2828         return 0;
2829 }
2830
2831 static struct usb_device_id hub_id_table [] = {
2832     { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
2833       .bDeviceClass = USB_CLASS_HUB},
2834     { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
2835       .bInterfaceClass = USB_CLASS_HUB},
2836     { }                                         /* Terminating entry */
2837 };
2838
2839 MODULE_DEVICE_TABLE (usb, hub_id_table);
2840
2841 static struct usb_driver hub_driver = {
2842         .name =         "hub",
2843         .probe =        hub_probe,
2844         .disconnect =   hub_disconnect,
2845         .suspend =      hub_suspend,
2846         .resume =       hub_resume,
2847         .pre_reset =    hub_pre_reset,
2848         .post_reset =   hub_post_reset,
2849         .ioctl =        hub_ioctl,
2850         .id_table =     hub_id_table,
2851         .supports_autosuspend = 1,
2852 };
2853
2854 int usb_hub_init(void)
2855 {
2856         if (usb_register(&hub_driver) < 0) {
2857                 printk(KERN_ERR "%s: can't register hub driver\n",
2858                         usbcore_name);
2859                 return -1;
2860         }
2861
2862         khubd_task = kthread_run(hub_thread, NULL, "khubd");
2863         if (!IS_ERR(khubd_task))
2864                 return 0;
2865
2866         /* Fall through if kernel_thread failed */
2867         usb_deregister(&hub_driver);
2868         printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
2869
2870         return -1;
2871 }
2872
2873 void usb_hub_cleanup(void)
2874 {
2875         kthread_stop(khubd_task);
2876
2877         /*
2878          * Hub resources are freed for us by usb_deregister. It calls
2879          * usb_driver_purge on every device which in turn calls that
2880          * devices disconnect function if it is using this driver.
2881          * The hub_disconnect function takes care of releasing the
2882          * individual hub resources. -greg
2883          */
2884         usb_deregister(&hub_driver);
2885 } /* usb_hub_cleanup() */
2886
2887 static int config_descriptors_changed(struct usb_device *udev)
2888 {
2889         unsigned                        index;
2890         unsigned                        len = 0;
2891         struct usb_config_descriptor    *buf;
2892
2893         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2894                 if (len < le16_to_cpu(udev->config[index].desc.wTotalLength))
2895                         len = le16_to_cpu(udev->config[index].desc.wTotalLength);
2896         }
2897         buf = kmalloc (len, GFP_KERNEL);
2898         if (buf == NULL) {
2899                 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
2900                 /* assume the worst */
2901                 return 1;
2902         }
2903         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2904                 int length;
2905                 int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
2906
2907                 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
2908                                 old_length);
2909                 if (length < old_length) {
2910                         dev_dbg(&udev->dev, "config index %d, error %d\n",
2911                                         index, length);
2912                         break;
2913                 }
2914                 if (memcmp (buf, udev->rawdescriptors[index], old_length)
2915                                 != 0) {
2916                         dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
2917                                 index, buf->bConfigurationValue);
2918                         break;
2919                 }
2920         }
2921         kfree(buf);
2922         return index != udev->descriptor.bNumConfigurations;
2923 }
2924
2925 /**
2926  * usb_reset_device - perform a USB port reset to reinitialize a device
2927  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2928  *
2929  * WARNING - don't use this routine to reset a composite device
2930  * (one with multiple interfaces owned by separate drivers)!
2931  * Use usb_reset_composite_device() instead.
2932  *
2933  * Do a port reset, reassign the device's address, and establish its
2934  * former operating configuration.  If the reset fails, or the device's
2935  * descriptors change from their values before the reset, or the original
2936  * configuration and altsettings cannot be restored, a flag will be set
2937  * telling khubd to pretend the device has been disconnected and then
2938  * re-connected.  All drivers will be unbound, and the device will be
2939  * re-enumerated and probed all over again.
2940  *
2941  * Returns 0 if the reset succeeded, -ENODEV if the device has been
2942  * flagged for logical disconnection, or some other negative error code
2943  * if the reset wasn't even attempted.
2944  *
2945  * The caller must own the device lock.  For example, it's safe to use
2946  * this from a driver probe() routine after downloading new firmware.
2947  * For calls that might not occur during probe(), drivers should lock
2948  * the device using usb_lock_device_for_reset().
2949  */
2950 int usb_reset_device(struct usb_device *udev)
2951 {
2952         struct usb_device               *parent_hdev = udev->parent;
2953         struct usb_hub                  *parent_hub;
2954         struct usb_device_descriptor    descriptor = udev->descriptor;
2955         int                             i, ret = 0;
2956         int                             port1 = udev->portnum;
2957
2958         if (udev->state == USB_STATE_NOTATTACHED ||
2959                         udev->state == USB_STATE_SUSPENDED) {
2960                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
2961                                 udev->state);
2962                 return -EINVAL;
2963         }
2964
2965         if (!parent_hdev) {
2966                 /* this requires hcd-specific logic; see OHCI hc_restart() */
2967                 dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
2968                 return -EISDIR;
2969         }
2970         parent_hub = hdev_to_hub(parent_hdev);
2971
2972         set_bit(port1, parent_hub->busy_bits);
2973         for (i = 0; i < SET_CONFIG_TRIES; ++i) {
2974
2975                 /* ep0 maxpacket size may change; let the HCD know about it.
2976                  * Other endpoints will be handled by re-enumeration. */
2977                 ep0_reinit(udev);
2978                 ret = hub_port_init(parent_hub, udev, port1, i);
2979                 if (ret >= 0)
2980                         break;
2981         }
2982         clear_bit(port1, parent_hub->busy_bits);
2983         if (!parent_hdev->parent && !parent_hub->busy_bits[0])
2984                 usb_enable_root_hub_irq(parent_hdev->bus);
2985
2986         if (ret < 0)
2987                 goto re_enumerate;
2988  
2989         /* Device might have changed firmware (DFU or similar) */
2990         if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
2991                         || config_descriptors_changed (udev)) {
2992                 dev_info(&udev->dev, "device firmware changed\n");
2993                 udev->descriptor = descriptor;  /* for disconnect() calls */
2994                 goto re_enumerate;
2995         }
2996   
2997         if (!udev->actconfig)
2998                 goto done;
2999
3000         ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3001                         USB_REQ_SET_CONFIGURATION, 0,
3002                         udev->actconfig->desc.bConfigurationValue, 0,
3003                         NULL, 0, USB_CTRL_SET_TIMEOUT);
3004         if (ret < 0) {
3005                 dev_err(&udev->dev,
3006                         "can't restore configuration #%d (error=%d)\n",
3007                         udev->actconfig->desc.bConfigurationValue, ret);
3008                 goto re_enumerate;
3009         }
3010         usb_set_device_state(udev, USB_STATE_CONFIGURED);
3011
3012         for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
3013                 struct usb_interface *intf = udev->actconfig->interface[i];
3014                 struct usb_interface_descriptor *desc;
3015
3016                 /* set_interface resets host side toggle even
3017                  * for altsetting zero.  the interface may have no driver.
3018                  */
3019                 desc = &intf->cur_altsetting->desc;
3020                 ret = usb_set_interface(udev, desc->bInterfaceNumber,
3021                         desc->bAlternateSetting);
3022                 if (ret < 0) {
3023                         dev_err(&udev->dev, "failed to restore interface %d "
3024                                 "altsetting %d (error=%d)\n",
3025                                 desc->bInterfaceNumber,
3026                                 desc->bAlternateSetting,
3027                                 ret);
3028                         goto re_enumerate;
3029                 }
3030         }
3031
3032 done:
3033         return 0;
3034  
3035 re_enumerate:
3036         hub_port_logical_disconnect(parent_hub, port1);
3037         return -ENODEV;
3038 }
3039 EXPORT_SYMBOL(usb_reset_device);
3040
3041 /**
3042  * usb_reset_composite_device - warn interface drivers and perform a USB port reset
3043  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
3044  * @iface: interface bound to the driver making the request (optional)
3045  *
3046  * Warns all drivers bound to registered interfaces (using their pre_reset
3047  * method), performs the port reset, and then lets the drivers know that
3048  * the reset is over (using their post_reset method).
3049  *
3050  * Return value is the same as for usb_reset_device().
3051  *
3052  * The caller must own the device lock.  For example, it's safe to use
3053  * this from a driver probe() routine after downloading new firmware.
3054  * For calls that might not occur during probe(), drivers should lock
3055  * the device using usb_lock_device_for_reset().
3056  *
3057  * The interface locks are acquired during the pre_reset stage and released
3058  * during the post_reset stage.  However if iface is not NULL and is
3059  * currently being probed, we assume that the caller already owns its
3060  * lock.
3061  */
3062 int usb_reset_composite_device(struct usb_device *udev,
3063                 struct usb_interface *iface)
3064 {
3065         int ret;
3066         struct usb_host_config *config = udev->actconfig;
3067
3068         if (udev->state == USB_STATE_NOTATTACHED ||
3069                         udev->state == USB_STATE_SUSPENDED) {
3070                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
3071                                 udev->state);
3072                 return -EINVAL;
3073         }
3074
3075         /* Prevent autosuspend during the reset */
3076         usb_autoresume_device(udev);
3077
3078         if (iface && iface->condition != USB_INTERFACE_BINDING)
3079                 iface = NULL;
3080
3081         if (config) {
3082                 int i;
3083                 struct usb_interface *cintf;
3084                 struct usb_driver *drv;
3085
3086                 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
3087                         cintf = config->interface[i];
3088                         if (cintf != iface)
3089                                 down(&cintf->dev.sem);
3090                         if (device_is_registered(&cintf->dev) &&
3091                                         cintf->dev.driver) {
3092                                 drv = to_usb_driver(cintf->dev.driver);
3093                                 if (drv->pre_reset)
3094                                         (drv->pre_reset)(cintf);
3095                         }
3096                 }
3097         }
3098
3099         ret = usb_reset_device(udev);
3100
3101         if (config) {
3102                 int i;
3103                 struct usb_interface *cintf;
3104                 struct usb_driver *drv;
3105
3106                 for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
3107                         cintf = config->interface[i];
3108                         if (device_is_registered(&cintf->dev) &&
3109                                         cintf->dev.driver) {
3110                                 drv = to_usb_driver(cintf->dev.driver);
3111                                 if (drv->post_reset)
3112                                         (drv->post_reset)(cintf);
3113                         }
3114                         if (cintf != iface)
3115                                 up(&cintf->dev.sem);
3116                 }
3117         }
3118
3119         usb_autosuspend_device(udev);
3120         return ret;
3121 }
3122 EXPORT_SYMBOL(usb_reset_composite_device);