[PATCH] USB: remove .owner field from struct usb_driver
[linux-2.6.git] / drivers / usb / core / hub.c
1 /*
2  * USB hub driver.
3  *
4  * (C) Copyright 1999 Linus Torvalds
5  * (C) Copyright 1999 Johannes Erdfelt
6  * (C) Copyright 1999 Gregory P. Smith
7  * (C) Copyright 2001 Brad Hards (bhards@bigpond.net.au)
8  *
9  */
10
11 #include <linux/config.h>
12 #include <linux/kernel.h>
13 #include <linux/errno.h>
14 #include <linux/module.h>
15 #include <linux/moduleparam.h>
16 #include <linux/completion.h>
17 #include <linux/sched.h>
18 #include <linux/list.h>
19 #include <linux/slab.h>
20 #include <linux/smp_lock.h>
21 #include <linux/ioctl.h>
22 #include <linux/usb.h>
23 #include <linux/usbdevice_fs.h>
24 #include <linux/kthread.h>
25
26 #include <asm/semaphore.h>
27 #include <asm/uaccess.h>
28 #include <asm/byteorder.h>
29
30 #include "usb.h"
31 #include "hcd.h"
32 #include "hub.h"
33
34 /* Protect struct usb_device->state and ->children members
35  * Note: Both are also protected by ->serialize, except that ->state can
36  * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
37 static DEFINE_SPINLOCK(device_state_lock);
38
39 /* khubd's worklist and its lock */
40 static DEFINE_SPINLOCK(hub_event_lock);
41 static LIST_HEAD(hub_event_list);       /* List of hubs needing servicing */
42
43 /* Wakes up khubd */
44 static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
45
46 static struct task_struct *khubd_task;
47
48 /* cycle leds on hubs that aren't blinking for attention */
49 static int blinkenlights = 0;
50 module_param (blinkenlights, bool, S_IRUGO);
51 MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
52
53 /*
54  * As of 2.6.10 we introduce a new USB device initialization scheme which
55  * closely resembles the way Windows works.  Hopefully it will be compatible
56  * with a wider range of devices than the old scheme.  However some previously
57  * working devices may start giving rise to "device not accepting address"
58  * errors; if that happens the user can try the old scheme by adjusting the
59  * following module parameters.
60  *
61  * For maximum flexibility there are two boolean parameters to control the
62  * hub driver's behavior.  On the first initialization attempt, if the
63  * "old_scheme_first" parameter is set then the old scheme will be used,
64  * otherwise the new scheme is used.  If that fails and "use_both_schemes"
65  * is set, then the driver will make another attempt, using the other scheme.
66  */
67 static int old_scheme_first = 0;
68 module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
69 MODULE_PARM_DESC(old_scheme_first,
70                  "start with the old device initialization scheme");
71
72 static int use_both_schemes = 1;
73 module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
74 MODULE_PARM_DESC(use_both_schemes,
75                 "try the other device initialization scheme if the "
76                 "first one fails");
77
78
79 #ifdef  DEBUG
80 static inline char *portspeed (int portstatus)
81 {
82         if (portstatus & (1 << USB_PORT_FEAT_HIGHSPEED))
83                 return "480 Mb/s";
84         else if (portstatus & (1 << USB_PORT_FEAT_LOWSPEED))
85                 return "1.5 Mb/s";
86         else
87                 return "12 Mb/s";
88 }
89 #endif
90
91 /* Note that hdev or one of its children must be locked! */
92 static inline struct usb_hub *hdev_to_hub(struct usb_device *hdev)
93 {
94         return usb_get_intfdata(hdev->actconfig->interface[0]);
95 }
96
97 /* USB 2.0 spec Section 11.24.4.5 */
98 static int get_hub_descriptor(struct usb_device *hdev, void *data, int size)
99 {
100         int i, ret;
101
102         for (i = 0; i < 3; i++) {
103                 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
104                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
105                         USB_DT_HUB << 8, 0, data, size,
106                         USB_CTRL_GET_TIMEOUT);
107                 if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
108                         return ret;
109         }
110         return -EINVAL;
111 }
112
113 /*
114  * USB 2.0 spec Section 11.24.2.1
115  */
116 static int clear_hub_feature(struct usb_device *hdev, int feature)
117 {
118         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
119                 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
120 }
121
122 /*
123  * USB 2.0 spec Section 11.24.2.2
124  */
125 static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
126 {
127         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
128                 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
129                 NULL, 0, 1000);
130 }
131
132 /*
133  * USB 2.0 spec Section 11.24.2.13
134  */
135 static int set_port_feature(struct usb_device *hdev, int port1, int feature)
136 {
137         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
138                 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
139                 NULL, 0, 1000);
140 }
141
142 /*
143  * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
144  * for info about using port indicators
145  */
146 static void set_port_led(
147         struct usb_hub *hub,
148         int port1,
149         int selector
150 )
151 {
152         int status = set_port_feature(hub->hdev, (selector << 8) | port1,
153                         USB_PORT_FEAT_INDICATOR);
154         if (status < 0)
155                 dev_dbg (hub->intfdev,
156                         "port %d indicator %s status %d\n",
157                         port1,
158                         ({ char *s; switch (selector) {
159                         case HUB_LED_AMBER: s = "amber"; break;
160                         case HUB_LED_GREEN: s = "green"; break;
161                         case HUB_LED_OFF: s = "off"; break;
162                         case HUB_LED_AUTO: s = "auto"; break;
163                         default: s = "??"; break;
164                         }; s; }),
165                         status);
166 }
167
168 #define LED_CYCLE_PERIOD        ((2*HZ)/3)
169
170 static void led_work (void *__hub)
171 {
172         struct usb_hub          *hub = __hub;
173         struct usb_device       *hdev = hub->hdev;
174         unsigned                i;
175         unsigned                changed = 0;
176         int                     cursor = -1;
177
178         if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
179                 return;
180
181         for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
182                 unsigned        selector, mode;
183
184                 /* 30%-50% duty cycle */
185
186                 switch (hub->indicator[i]) {
187                 /* cycle marker */
188                 case INDICATOR_CYCLE:
189                         cursor = i;
190                         selector = HUB_LED_AUTO;
191                         mode = INDICATOR_AUTO;
192                         break;
193                 /* blinking green = sw attention */
194                 case INDICATOR_GREEN_BLINK:
195                         selector = HUB_LED_GREEN;
196                         mode = INDICATOR_GREEN_BLINK_OFF;
197                         break;
198                 case INDICATOR_GREEN_BLINK_OFF:
199                         selector = HUB_LED_OFF;
200                         mode = INDICATOR_GREEN_BLINK;
201                         break;
202                 /* blinking amber = hw attention */
203                 case INDICATOR_AMBER_BLINK:
204                         selector = HUB_LED_AMBER;
205                         mode = INDICATOR_AMBER_BLINK_OFF;
206                         break;
207                 case INDICATOR_AMBER_BLINK_OFF:
208                         selector = HUB_LED_OFF;
209                         mode = INDICATOR_AMBER_BLINK;
210                         break;
211                 /* blink green/amber = reserved */
212                 case INDICATOR_ALT_BLINK:
213                         selector = HUB_LED_GREEN;
214                         mode = INDICATOR_ALT_BLINK_OFF;
215                         break;
216                 case INDICATOR_ALT_BLINK_OFF:
217                         selector = HUB_LED_AMBER;
218                         mode = INDICATOR_ALT_BLINK;
219                         break;
220                 default:
221                         continue;
222                 }
223                 if (selector != HUB_LED_AUTO)
224                         changed = 1;
225                 set_port_led(hub, i + 1, selector);
226                 hub->indicator[i] = mode;
227         }
228         if (!changed && blinkenlights) {
229                 cursor++;
230                 cursor %= hub->descriptor->bNbrPorts;
231                 set_port_led(hub, cursor + 1, HUB_LED_GREEN);
232                 hub->indicator[cursor] = INDICATOR_CYCLE;
233                 changed++;
234         }
235         if (changed)
236                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
237 }
238
239 /* use a short timeout for hub/port status fetches */
240 #define USB_STS_TIMEOUT         1000
241 #define USB_STS_RETRIES         5
242
243 /*
244  * USB 2.0 spec Section 11.24.2.6
245  */
246 static int get_hub_status(struct usb_device *hdev,
247                 struct usb_hub_status *data)
248 {
249         int i, status = -ETIMEDOUT;
250
251         for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
252                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
253                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
254                         data, sizeof(*data), USB_STS_TIMEOUT);
255         }
256         return status;
257 }
258
259 /*
260  * USB 2.0 spec Section 11.24.2.7
261  */
262 static int get_port_status(struct usb_device *hdev, int port1,
263                 struct usb_port_status *data)
264 {
265         int i, status = -ETIMEDOUT;
266
267         for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
268                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
269                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
270                         data, sizeof(*data), USB_STS_TIMEOUT);
271         }
272         return status;
273 }
274
275 static void kick_khubd(struct usb_hub *hub)
276 {
277         unsigned long   flags;
278
279         spin_lock_irqsave(&hub_event_lock, flags);
280         if (list_empty(&hub->event_list)) {
281                 list_add_tail(&hub->event_list, &hub_event_list);
282                 wake_up(&khubd_wait);
283         }
284         spin_unlock_irqrestore(&hub_event_lock, flags);
285 }
286
287 void usb_kick_khubd(struct usb_device *hdev)
288 {
289         kick_khubd(hdev_to_hub(hdev));
290 }
291
292
293 /* completion function, fires on port status changes and various faults */
294 static void hub_irq(struct urb *urb, struct pt_regs *regs)
295 {
296         struct usb_hub *hub = (struct usb_hub *)urb->context;
297         int status;
298         int i;
299         unsigned long bits;
300
301         switch (urb->status) {
302         case -ENOENT:           /* synchronous unlink */
303         case -ECONNRESET:       /* async unlink */
304         case -ESHUTDOWN:        /* hardware going away */
305                 return;
306
307         default:                /* presumably an error */
308                 /* Cause a hub reset after 10 consecutive errors */
309                 dev_dbg (hub->intfdev, "transfer --> %d\n", urb->status);
310                 if ((++hub->nerrors < 10) || hub->error)
311                         goto resubmit;
312                 hub->error = urb->status;
313                 /* FALL THROUGH */
314         
315         /* let khubd handle things */
316         case 0:                 /* we got data:  port status changed */
317                 bits = 0;
318                 for (i = 0; i < urb->actual_length; ++i)
319                         bits |= ((unsigned long) ((*hub->buffer)[i]))
320                                         << (i*8);
321                 hub->event_bits[0] = bits;
322                 break;
323         }
324
325         hub->nerrors = 0;
326
327         /* Something happened, let khubd figure it out */
328         kick_khubd(hub);
329
330 resubmit:
331         if (hub->quiescing)
332                 return;
333
334         if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
335                         && status != -ENODEV && status != -EPERM)
336                 dev_err (hub->intfdev, "resubmit --> %d\n", status);
337 }
338
339 /* USB 2.0 spec Section 11.24.2.3 */
340 static inline int
341 hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
342 {
343         return usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
344                                HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
345                                tt, NULL, 0, 1000);
346 }
347
348 /*
349  * enumeration blocks khubd for a long time. we use keventd instead, since
350  * long blocking there is the exception, not the rule.  accordingly, HCDs
351  * talking to TTs must queue control transfers (not just bulk and iso), so
352  * both can talk to the same hub concurrently.
353  */
354 static void hub_tt_kevent (void *arg)
355 {
356         struct usb_hub          *hub = arg;
357         unsigned long           flags;
358
359         spin_lock_irqsave (&hub->tt.lock, flags);
360         while (!list_empty (&hub->tt.clear_list)) {
361                 struct list_head        *temp;
362                 struct usb_tt_clear     *clear;
363                 struct usb_device       *hdev = hub->hdev;
364                 int                     status;
365
366                 temp = hub->tt.clear_list.next;
367                 clear = list_entry (temp, struct usb_tt_clear, clear_list);
368                 list_del (&clear->clear_list);
369
370                 /* drop lock so HCD can concurrently report other TT errors */
371                 spin_unlock_irqrestore (&hub->tt.lock, flags);
372                 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
373                 spin_lock_irqsave (&hub->tt.lock, flags);
374
375                 if (status)
376                         dev_err (&hdev->dev,
377                                 "clear tt %d (%04x) error %d\n",
378                                 clear->tt, clear->devinfo, status);
379                 kfree(clear);
380         }
381         spin_unlock_irqrestore (&hub->tt.lock, flags);
382 }
383
384 /**
385  * usb_hub_tt_clear_buffer - clear control/bulk TT state in high speed hub
386  * @udev: the device whose split transaction failed
387  * @pipe: identifies the endpoint of the failed transaction
388  *
389  * High speed HCDs use this to tell the hub driver that some split control or
390  * bulk transaction failed in a way that requires clearing internal state of
391  * a transaction translator.  This is normally detected (and reported) from
392  * interrupt context.
393  *
394  * It may not be possible for that hub to handle additional full (or low)
395  * speed transactions until that state is fully cleared out.
396  */
397 void usb_hub_tt_clear_buffer (struct usb_device *udev, int pipe)
398 {
399         struct usb_tt           *tt = udev->tt;
400         unsigned long           flags;
401         struct usb_tt_clear     *clear;
402
403         /* we've got to cope with an arbitrary number of pending TT clears,
404          * since each TT has "at least two" buffers that can need it (and
405          * there can be many TTs per hub).  even if they're uncommon.
406          */
407         if ((clear = kmalloc (sizeof *clear, SLAB_ATOMIC)) == NULL) {
408                 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
409                 /* FIXME recover somehow ... RESET_TT? */
410                 return;
411         }
412
413         /* info that CLEAR_TT_BUFFER needs */
414         clear->tt = tt->multi ? udev->ttport : 1;
415         clear->devinfo = usb_pipeendpoint (pipe);
416         clear->devinfo |= udev->devnum << 4;
417         clear->devinfo |= usb_pipecontrol (pipe)
418                         ? (USB_ENDPOINT_XFER_CONTROL << 11)
419                         : (USB_ENDPOINT_XFER_BULK << 11);
420         if (usb_pipein (pipe))
421                 clear->devinfo |= 1 << 15;
422         
423         /* tell keventd to clear state for this TT */
424         spin_lock_irqsave (&tt->lock, flags);
425         list_add_tail (&clear->clear_list, &tt->clear_list);
426         schedule_work (&tt->kevent);
427         spin_unlock_irqrestore (&tt->lock, flags);
428 }
429
430 static void hub_power_on(struct usb_hub *hub)
431 {
432         int port1;
433         unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
434         u16 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
435
436         /* if hub supports power switching, enable power on each port */
437         if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2) {
438                 dev_dbg(hub->intfdev, "enabling power on all ports\n");
439                 for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
440                         set_port_feature(hub->hdev, port1,
441                                         USB_PORT_FEAT_POWER);
442         }
443
444         /* Wait at least 100 msec for power to become stable */
445         msleep(max(pgood_delay, (unsigned) 100));
446 }
447
448 static inline void __hub_quiesce(struct usb_hub *hub)
449 {
450         /* (nonblocking) khubd and related activity won't re-trigger */
451         hub->quiescing = 1;
452         hub->activating = 0;
453         hub->resume_root_hub = 0;
454 }
455
456 static void hub_quiesce(struct usb_hub *hub)
457 {
458         /* (blocking) stop khubd and related activity */
459         __hub_quiesce(hub);
460         usb_kill_urb(hub->urb);
461         if (hub->has_indicators)
462                 cancel_delayed_work(&hub->leds);
463         if (hub->has_indicators || hub->tt.hub)
464                 flush_scheduled_work();
465 }
466
467 static void hub_activate(struct usb_hub *hub)
468 {
469         int     status;
470
471         hub->quiescing = 0;
472         hub->activating = 1;
473         hub->resume_root_hub = 0;
474         status = usb_submit_urb(hub->urb, GFP_NOIO);
475         if (status < 0)
476                 dev_err(hub->intfdev, "activate --> %d\n", status);
477         if (hub->has_indicators && blinkenlights)
478                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
479
480         /* scan all ports ASAP */
481         kick_khubd(hub);
482 }
483
484 static int hub_hub_status(struct usb_hub *hub,
485                 u16 *status, u16 *change)
486 {
487         int ret;
488
489         ret = get_hub_status(hub->hdev, &hub->status->hub);
490         if (ret < 0)
491                 dev_err (hub->intfdev,
492                         "%s failed (err = %d)\n", __FUNCTION__, ret);
493         else {
494                 *status = le16_to_cpu(hub->status->hub.wHubStatus);
495                 *change = le16_to_cpu(hub->status->hub.wHubChange); 
496                 ret = 0;
497         }
498         return ret;
499 }
500
501 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
502 {
503         struct usb_device *hdev = hub->hdev;
504         int ret;
505
506         if (hdev->children[port1-1] && set_state) {
507                 usb_set_device_state(hdev->children[port1-1],
508                                 USB_STATE_NOTATTACHED);
509         }
510         ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
511         if (ret)
512                 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
513                         port1, ret);
514
515         return ret;
516 }
517
518 static int hub_configure(struct usb_hub *hub,
519         struct usb_endpoint_descriptor *endpoint)
520 {
521         struct usb_device *hdev = hub->hdev;
522         struct device *hub_dev = hub->intfdev;
523         u16 hubstatus, hubchange;
524         u16 wHubCharacteristics;
525         unsigned int pipe;
526         int maxp, ret;
527         char *message;
528
529         hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
530                         &hub->buffer_dma);
531         if (!hub->buffer) {
532                 message = "can't allocate hub irq buffer";
533                 ret = -ENOMEM;
534                 goto fail;
535         }
536
537         hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
538         if (!hub->status) {
539                 message = "can't kmalloc hub status buffer";
540                 ret = -ENOMEM;
541                 goto fail;
542         }
543
544         hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
545         if (!hub->descriptor) {
546                 message = "can't kmalloc hub descriptor";
547                 ret = -ENOMEM;
548                 goto fail;
549         }
550
551         /* Request the entire hub descriptor.
552          * hub->descriptor can handle USB_MAXCHILDREN ports,
553          * but the hub can/will return fewer bytes here.
554          */
555         ret = get_hub_descriptor(hdev, hub->descriptor,
556                         sizeof(*hub->descriptor));
557         if (ret < 0) {
558                 message = "can't read hub descriptor";
559                 goto fail;
560         } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
561                 message = "hub has too many ports!";
562                 ret = -ENODEV;
563                 goto fail;
564         }
565
566         hdev->maxchild = hub->descriptor->bNbrPorts;
567         dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
568                 (hdev->maxchild == 1) ? "" : "s");
569
570         wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
571
572         if (wHubCharacteristics & HUB_CHAR_COMPOUND) {
573                 int     i;
574                 char    portstr [USB_MAXCHILDREN + 1];
575
576                 for (i = 0; i < hdev->maxchild; i++)
577                         portstr[i] = hub->descriptor->DeviceRemovable
578                                     [((i + 1) / 8)] & (1 << ((i + 1) % 8))
579                                 ? 'F' : 'R';
580                 portstr[hdev->maxchild] = 0;
581                 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
582         } else
583                 dev_dbg(hub_dev, "standalone hub\n");
584
585         switch (wHubCharacteristics & HUB_CHAR_LPSM) {
586                 case 0x00:
587                         dev_dbg(hub_dev, "ganged power switching\n");
588                         break;
589                 case 0x01:
590                         dev_dbg(hub_dev, "individual port power switching\n");
591                         break;
592                 case 0x02:
593                 case 0x03:
594                         dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
595                         break;
596         }
597
598         switch (wHubCharacteristics & HUB_CHAR_OCPM) {
599                 case 0x00:
600                         dev_dbg(hub_dev, "global over-current protection\n");
601                         break;
602                 case 0x08:
603                         dev_dbg(hub_dev, "individual port over-current protection\n");
604                         break;
605                 case 0x10:
606                 case 0x18:
607                         dev_dbg(hub_dev, "no over-current protection\n");
608                         break;
609         }
610
611         spin_lock_init (&hub->tt.lock);
612         INIT_LIST_HEAD (&hub->tt.clear_list);
613         INIT_WORK (&hub->tt.kevent, hub_tt_kevent, hub);
614         switch (hdev->descriptor.bDeviceProtocol) {
615                 case 0:
616                         break;
617                 case 1:
618                         dev_dbg(hub_dev, "Single TT\n");
619                         hub->tt.hub = hdev;
620                         break;
621                 case 2:
622                         ret = usb_set_interface(hdev, 0, 1);
623                         if (ret == 0) {
624                                 dev_dbg(hub_dev, "TT per port\n");
625                                 hub->tt.multi = 1;
626                         } else
627                                 dev_err(hub_dev, "Using single TT (err %d)\n",
628                                         ret);
629                         hub->tt.hub = hdev;
630                         break;
631                 default:
632                         dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
633                                 hdev->descriptor.bDeviceProtocol);
634                         break;
635         }
636
637         /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
638         switch (wHubCharacteristics & HUB_CHAR_TTTT) {
639                 case HUB_TTTT_8_BITS:
640                         if (hdev->descriptor.bDeviceProtocol != 0) {
641                                 hub->tt.think_time = 666;
642                                 dev_dbg(hub_dev, "TT requires at most %d "
643                                                 "FS bit times (%d ns)\n",
644                                         8, hub->tt.think_time);
645                         }
646                         break;
647                 case HUB_TTTT_16_BITS:
648                         hub->tt.think_time = 666 * 2;
649                         dev_dbg(hub_dev, "TT requires at most %d "
650                                         "FS bit times (%d ns)\n",
651                                 16, hub->tt.think_time);
652                         break;
653                 case HUB_TTTT_24_BITS:
654                         hub->tt.think_time = 666 * 3;
655                         dev_dbg(hub_dev, "TT requires at most %d "
656                                         "FS bit times (%d ns)\n",
657                                 24, hub->tt.think_time);
658                         break;
659                 case HUB_TTTT_32_BITS:
660                         hub->tt.think_time = 666 * 4;
661                         dev_dbg(hub_dev, "TT requires at most %d "
662                                         "FS bit times (%d ns)\n",
663                                 32, hub->tt.think_time);
664                         break;
665         }
666
667         /* probe() zeroes hub->indicator[] */
668         if (wHubCharacteristics & HUB_CHAR_PORTIND) {
669                 hub->has_indicators = 1;
670                 dev_dbg(hub_dev, "Port indicators are supported\n");
671         }
672
673         dev_dbg(hub_dev, "power on to power good time: %dms\n",
674                 hub->descriptor->bPwrOn2PwrGood * 2);
675
676         /* power budgeting mostly matters with bus-powered hubs,
677          * and battery-powered root hubs (may provide just 8 mA).
678          */
679         ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
680         if (ret < 0) {
681                 message = "can't get hub status";
682                 goto fail;
683         }
684         le16_to_cpus(&hubstatus);
685         if (hdev == hdev->bus->root_hub) {
686                 struct usb_hcd *hcd =
687                                 container_of(hdev->bus, struct usb_hcd, self);
688
689                 hub->power_budget = min(500u, hcd->power_budget) / 2;
690         } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
691                 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
692                         hub->descriptor->bHubContrCurrent);
693                 hub->power_budget = (501 - hub->descriptor->bHubContrCurrent)
694                                         / 2;
695         }
696         if (hub->power_budget)
697                 dev_dbg(hub_dev, "%dmA bus power budget for children\n",
698                         hub->power_budget * 2);
699
700
701         ret = hub_hub_status(hub, &hubstatus, &hubchange);
702         if (ret < 0) {
703                 message = "can't get hub status";
704                 goto fail;
705         }
706
707         /* local power status reports aren't always correct */
708         if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
709                 dev_dbg(hub_dev, "local power source is %s\n",
710                         (hubstatus & HUB_STATUS_LOCAL_POWER)
711                         ? "lost (inactive)" : "good");
712
713         if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
714                 dev_dbg(hub_dev, "%sover-current condition exists\n",
715                         (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
716
717         /* set up the interrupt endpoint */
718         pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
719         maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
720
721         if (maxp > sizeof(*hub->buffer))
722                 maxp = sizeof(*hub->buffer);
723
724         hub->urb = usb_alloc_urb(0, GFP_KERNEL);
725         if (!hub->urb) {
726                 message = "couldn't allocate interrupt urb";
727                 ret = -ENOMEM;
728                 goto fail;
729         }
730
731         usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
732                 hub, endpoint->bInterval);
733         hub->urb->transfer_dma = hub->buffer_dma;
734         hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
735
736         /* maybe cycle the hub leds */
737         if (hub->has_indicators && blinkenlights)
738                 hub->indicator [0] = INDICATOR_CYCLE;
739
740         hub_power_on(hub);
741         hub_activate(hub);
742         return 0;
743
744 fail:
745         dev_err (hub_dev, "config failed, %s (err %d)\n",
746                         message, ret);
747         /* hub_disconnect() frees urb and descriptor */
748         return ret;
749 }
750
751 static unsigned highspeed_hubs;
752
753 /* Called after the hub driver is unbound from a hub with children */
754 static void hub_remove_children_work(void *__hub)
755 {
756         struct usb_hub          *hub = __hub;
757         struct usb_device       *hdev = hub->hdev;
758         int                     i;
759
760         kfree(hub);
761
762         usb_lock_device(hdev);
763         for (i = 0; i < hdev->maxchild; ++i) {
764                 if (hdev->children[i])
765                         usb_disconnect(&hdev->children[i]);
766         }
767         usb_unlock_device(hdev);
768         usb_put_dev(hdev);
769 }
770
771 static void hub_disconnect(struct usb_interface *intf)
772 {
773         struct usb_hub *hub = usb_get_intfdata (intf);
774         struct usb_device *hdev;
775         int n, port1;
776
777         usb_set_intfdata (intf, NULL);
778         hdev = hub->hdev;
779
780         if (hdev->speed == USB_SPEED_HIGH)
781                 highspeed_hubs--;
782
783         hub_quiesce(hub);
784         usb_free_urb(hub->urb);
785         hub->urb = NULL;
786
787         spin_lock_irq(&hub_event_lock);
788         list_del_init(&hub->event_list);
789         spin_unlock_irq(&hub_event_lock);
790
791         kfree(hub->descriptor);
792         hub->descriptor = NULL;
793
794         kfree(hub->status);
795         hub->status = NULL;
796
797         if (hub->buffer) {
798                 usb_buffer_free(hdev, sizeof(*hub->buffer), hub->buffer,
799                                 hub->buffer_dma);
800                 hub->buffer = NULL;
801         }
802
803         /* If there are any children then this is an unbind only, not a
804          * physical disconnection.  The active ports must be disabled
805          * and later on we must call usb_disconnect().  We can't call
806          * it now because we may not hold the hub's device lock.
807          */
808         n = 0;
809         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
810                 if (hdev->children[port1 - 1]) {
811                         ++n;
812                         hub_port_disable(hub, port1, 1);
813                 }
814         }
815
816         if (n == 0)
817                 kfree(hub);
818         else {
819                 /* Reuse the hub->leds work_struct for our own purposes */
820                 INIT_WORK(&hub->leds, hub_remove_children_work, hub);
821                 schedule_work(&hub->leds);
822                 usb_get_dev(hdev);
823         }
824 }
825
826 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
827 {
828         struct usb_host_interface *desc;
829         struct usb_endpoint_descriptor *endpoint;
830         struct usb_device *hdev;
831         struct usb_hub *hub;
832
833         desc = intf->cur_altsetting;
834         hdev = interface_to_usbdev(intf);
835
836         /* Some hubs have a subclass of 1, which AFAICT according to the */
837         /*  specs is not defined, but it works */
838         if ((desc->desc.bInterfaceSubClass != 0) &&
839             (desc->desc.bInterfaceSubClass != 1)) {
840 descriptor_error:
841                 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
842                 return -EIO;
843         }
844
845         /* Multiple endpoints? What kind of mutant ninja-hub is this? */
846         if (desc->desc.bNumEndpoints != 1)
847                 goto descriptor_error;
848
849         endpoint = &desc->endpoint[0].desc;
850
851         /* Output endpoint? Curiouser and curiouser.. */
852         if (!(endpoint->bEndpointAddress & USB_DIR_IN))
853                 goto descriptor_error;
854
855         /* If it's not an interrupt endpoint, we'd better punt! */
856         if ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
857                         != USB_ENDPOINT_XFER_INT)
858                 goto descriptor_error;
859
860         /* We found a hub */
861         dev_info (&intf->dev, "USB hub found\n");
862
863         hub = kzalloc(sizeof(*hub), GFP_KERNEL);
864         if (!hub) {
865                 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
866                 return -ENOMEM;
867         }
868
869         INIT_LIST_HEAD(&hub->event_list);
870         hub->intfdev = &intf->dev;
871         hub->hdev = hdev;
872         INIT_WORK(&hub->leds, led_work, hub);
873
874         usb_set_intfdata (intf, hub);
875
876         if (hdev->speed == USB_SPEED_HIGH)
877                 highspeed_hubs++;
878
879         if (hub_configure(hub, endpoint) >= 0)
880                 return 0;
881
882         hub_disconnect (intf);
883         return -ENODEV;
884 }
885
886 static int
887 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
888 {
889         struct usb_device *hdev = interface_to_usbdev (intf);
890
891         /* assert ifno == 0 (part of hub spec) */
892         switch (code) {
893         case USBDEVFS_HUB_PORTINFO: {
894                 struct usbdevfs_hub_portinfo *info = user_data;
895                 int i;
896
897                 spin_lock_irq(&device_state_lock);
898                 if (hdev->devnum <= 0)
899                         info->nports = 0;
900                 else {
901                         info->nports = hdev->maxchild;
902                         for (i = 0; i < info->nports; i++) {
903                                 if (hdev->children[i] == NULL)
904                                         info->port[i] = 0;
905                                 else
906                                         info->port[i] =
907                                                 hdev->children[i]->devnum;
908                         }
909                 }
910                 spin_unlock_irq(&device_state_lock);
911
912                 return info->nports + 1;
913                 }
914
915         default:
916                 return -ENOSYS;
917         }
918 }
919
920 /* caller has locked the hub device */
921 static void hub_pre_reset(struct usb_hub *hub)
922 {
923         struct usb_device *hdev = hub->hdev;
924         int i;
925
926         for (i = 0; i < hdev->maxchild; ++i) {
927                 if (hdev->children[i])
928                         usb_disconnect(&hdev->children[i]);
929         }
930         hub_quiesce(hub);
931 }
932
933 /* caller has locked the hub device */
934 static void hub_post_reset(struct usb_hub *hub)
935 {
936         hub_activate(hub);
937         hub_power_on(hub);
938 }
939
940
941 /* grab device/port lock, returning index of that port (zero based).
942  * protects the upstream link used by this device from concurrent
943  * tree operations like suspend, resume, reset, and disconnect, which
944  * apply to everything downstream of a given port.
945  */
946 static int locktree(struct usb_device *udev)
947 {
948         int                     t;
949         struct usb_device       *hdev;
950
951         if (!udev)
952                 return -ENODEV;
953
954         /* root hub is always the first lock in the series */
955         hdev = udev->parent;
956         if (!hdev) {
957                 usb_lock_device(udev);
958                 return 0;
959         }
960
961         /* on the path from root to us, lock everything from
962          * top down, dropping parent locks when not needed
963          */
964         t = locktree(hdev);
965         if (t < 0)
966                 return t;
967         for (t = 0; t < hdev->maxchild; t++) {
968                 if (hdev->children[t] == udev) {
969                         /* everything is fail-fast once disconnect
970                          * processing starts
971                          */
972                         if (udev->state == USB_STATE_NOTATTACHED)
973                                 break;
974
975                         /* when everyone grabs locks top->bottom,
976                          * non-overlapping work may be concurrent
977                          */
978                         down(&udev->serialize);
979                         up(&hdev->serialize);
980                         return t + 1;
981                 }
982         }
983         usb_unlock_device(hdev);
984         return -ENODEV;
985 }
986
987 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
988 {
989         int i;
990
991         for (i = 0; i < udev->maxchild; ++i) {
992                 if (udev->children[i])
993                         recursively_mark_NOTATTACHED(udev->children[i]);
994         }
995         udev->state = USB_STATE_NOTATTACHED;
996 }
997
998 /**
999  * usb_set_device_state - change a device's current state (usbcore, hcds)
1000  * @udev: pointer to device whose state should be changed
1001  * @new_state: new state value to be stored
1002  *
1003  * udev->state is _not_ fully protected by the device lock.  Although
1004  * most transitions are made only while holding the lock, the state can
1005  * can change to USB_STATE_NOTATTACHED at almost any time.  This
1006  * is so that devices can be marked as disconnected as soon as possible,
1007  * without having to wait for any semaphores to be released.  As a result,
1008  * all changes to any device's state must be protected by the
1009  * device_state_lock spinlock.
1010  *
1011  * Once a device has been added to the device tree, all changes to its state
1012  * should be made using this routine.  The state should _not_ be set directly.
1013  *
1014  * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1015  * Otherwise udev->state is set to new_state, and if new_state is
1016  * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1017  * to USB_STATE_NOTATTACHED.
1018  */
1019 void usb_set_device_state(struct usb_device *udev,
1020                 enum usb_device_state new_state)
1021 {
1022         unsigned long flags;
1023
1024         spin_lock_irqsave(&device_state_lock, flags);
1025         if (udev->state == USB_STATE_NOTATTACHED)
1026                 ;       /* do nothing */
1027         else if (new_state != USB_STATE_NOTATTACHED) {
1028                 udev->state = new_state;
1029                 if (new_state == USB_STATE_CONFIGURED)
1030                         device_init_wakeup(&udev->dev,
1031                                 (udev->actconfig->desc.bmAttributes
1032                                  & USB_CONFIG_ATT_WAKEUP));
1033                 else if (new_state != USB_STATE_SUSPENDED)
1034                         device_init_wakeup(&udev->dev, 0);
1035         } else
1036                 recursively_mark_NOTATTACHED(udev);
1037         spin_unlock_irqrestore(&device_state_lock, flags);
1038 }
1039 EXPORT_SYMBOL(usb_set_device_state);
1040
1041
1042 #ifdef CONFIG_PM
1043
1044 /**
1045  * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
1046  * @rhdev: struct usb_device for the root hub
1047  *
1048  * The USB host controller driver calls this function when its root hub
1049  * is resumed and Vbus power has been interrupted or the controller
1050  * has been reset.  The routine marks all the children of the root hub
1051  * as NOTATTACHED and marks logical connect-change events on their ports.
1052  */
1053 void usb_root_hub_lost_power(struct usb_device *rhdev)
1054 {
1055         struct usb_hub *hub;
1056         int port1;
1057         unsigned long flags;
1058
1059         dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
1060         spin_lock_irqsave(&device_state_lock, flags);
1061         hub = hdev_to_hub(rhdev);
1062         for (port1 = 1; port1 <= rhdev->maxchild; ++port1) {
1063                 if (rhdev->children[port1 - 1]) {
1064                         recursively_mark_NOTATTACHED(
1065                                         rhdev->children[port1 - 1]);
1066                         set_bit(port1, hub->change_bits);
1067                 }
1068         }
1069         spin_unlock_irqrestore(&device_state_lock, flags);
1070 }
1071 EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
1072
1073 #endif
1074
1075 static void choose_address(struct usb_device *udev)
1076 {
1077         int             devnum;
1078         struct usb_bus  *bus = udev->bus;
1079
1080         /* If khubd ever becomes multithreaded, this will need a lock */
1081
1082         /* Try to allocate the next devnum beginning at bus->devnum_next. */
1083         devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1084                         bus->devnum_next);
1085         if (devnum >= 128)
1086                 devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
1087
1088         bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1089
1090         if (devnum < 128) {
1091                 set_bit(devnum, bus->devmap.devicemap);
1092                 udev->devnum = devnum;
1093         }
1094 }
1095
1096 static void release_address(struct usb_device *udev)
1097 {
1098         if (udev->devnum > 0) {
1099                 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1100                 udev->devnum = -1;
1101         }
1102 }
1103
1104 /**
1105  * usb_disconnect - disconnect a device (usbcore-internal)
1106  * @pdev: pointer to device being disconnected
1107  * Context: !in_interrupt ()
1108  *
1109  * Something got disconnected. Get rid of it and all of its children.
1110  *
1111  * If *pdev is a normal device then the parent hub must already be locked.
1112  * If *pdev is a root hub then this routine will acquire the
1113  * usb_bus_list_lock on behalf of the caller.
1114  *
1115  * Only hub drivers (including virtual root hub drivers for host
1116  * controllers) should ever call this.
1117  *
1118  * This call is synchronous, and may not be used in an interrupt context.
1119  */
1120 void usb_disconnect(struct usb_device **pdev)
1121 {
1122         struct usb_device       *udev = *pdev;
1123         int                     i;
1124
1125         if (!udev) {
1126                 pr_debug ("%s nodev\n", __FUNCTION__);
1127                 return;
1128         }
1129
1130         /* mark the device as inactive, so any further urb submissions for
1131          * this device (and any of its children) will fail immediately.
1132          * this quiesces everyting except pending urbs.
1133          */
1134         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1135
1136         /* lock the bus list on behalf of HCDs unregistering their root hubs */
1137         if (!udev->parent) {
1138                 down(&usb_bus_list_lock);
1139                 usb_lock_device(udev);
1140         } else
1141                 down(&udev->serialize);
1142
1143         dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1144
1145         /* Free up all the children before we remove this device */
1146         for (i = 0; i < USB_MAXCHILDREN; i++) {
1147                 if (udev->children[i])
1148                         usb_disconnect(&udev->children[i]);
1149         }
1150
1151         /* deallocate hcd/hardware state ... nuking all pending urbs and
1152          * cleaning up all state associated with the current configuration
1153          * so that the hardware is now fully quiesced.
1154          */
1155         usb_disable_device(udev, 0);
1156
1157         usb_notify_remove_device(udev);
1158
1159         /* Free the device number, remove the /proc/bus/usb entry and
1160          * the sysfs attributes, and delete the parent's children[]
1161          * (or root_hub) pointer.
1162          */
1163         dev_dbg (&udev->dev, "unregistering device\n");
1164         release_address(udev);
1165         usb_remove_sysfs_dev_files(udev);
1166
1167         /* Avoid races with recursively_mark_NOTATTACHED() */
1168         spin_lock_irq(&device_state_lock);
1169         *pdev = NULL;
1170         spin_unlock_irq(&device_state_lock);
1171
1172         if (!udev->parent) {
1173                 usb_unlock_device(udev);
1174                 up(&usb_bus_list_lock);
1175         } else
1176                 up(&udev->serialize);
1177
1178         device_unregister(&udev->dev);
1179 }
1180
1181 static int choose_configuration(struct usb_device *udev)
1182 {
1183         int c, i;
1184
1185         /* NOTE: this should interact with hub power budgeting */
1186
1187         c = udev->config[0].desc.bConfigurationValue;
1188         if (udev->descriptor.bNumConfigurations != 1) {
1189                 for (i = 0; i < udev->descriptor.bNumConfigurations; i++) {
1190                         struct usb_interface_descriptor *desc;
1191
1192                         /* heuristic:  Linux is more likely to have class
1193                          * drivers, so avoid vendor-specific interfaces.
1194                          */
1195                         desc = &udev->config[i].intf_cache[0]
1196                                         ->altsetting->desc;
1197                         if (desc->bInterfaceClass == USB_CLASS_VENDOR_SPEC)
1198                                 continue;
1199                         /* COMM/2/all is CDC ACM, except 0xff is MSFT RNDIS.
1200                          * MSFT needs this to be the first config; never use
1201                          * it as the default unless Linux has host-side RNDIS.
1202                          * A second config would ideally be CDC-Ethernet, but
1203                          * may instead be the "vendor specific" CDC subset
1204                          * long used by ARM Linux for sa1100 or pxa255.
1205                          */
1206                         if (desc->bInterfaceClass == USB_CLASS_COMM
1207                                         && desc->bInterfaceSubClass == 2
1208                                         && desc->bInterfaceProtocol == 0xff) {
1209                                 c = udev->config[1].desc.bConfigurationValue;
1210                                 continue;
1211                         }
1212                         c = udev->config[i].desc.bConfigurationValue;
1213                         break;
1214                 }
1215                 dev_info(&udev->dev,
1216                         "configuration #%d chosen from %d choices\n",
1217                         c, udev->descriptor.bNumConfigurations);
1218         }
1219         return c;
1220 }
1221
1222 #ifdef DEBUG
1223 static void show_string(struct usb_device *udev, char *id, char *string)
1224 {
1225         if (!string)
1226                 return;
1227         dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1228 }
1229
1230 #else
1231 static inline void show_string(struct usb_device *udev, char *id, char *string)
1232 {}
1233 #endif
1234
1235
1236 #ifdef  CONFIG_USB_OTG
1237 #include "otg_whitelist.h"
1238 #endif
1239
1240 /**
1241  * usb_new_device - perform initial device setup (usbcore-internal)
1242  * @udev: newly addressed device (in ADDRESS state)
1243  *
1244  * This is called with devices which have been enumerated, but not yet
1245  * configured.  The device descriptor is available, but not descriptors
1246  * for any device configuration.  The caller must have locked udev and
1247  * either the parent hub (if udev is a normal device) or else the
1248  * usb_bus_list_lock (if udev is a root hub).  The parent's pointer to
1249  * udev has already been installed, but udev is not yet visible through
1250  * sysfs or other filesystem code.
1251  *
1252  * Returns 0 for success (device is configured and listed, with its
1253  * interfaces, in sysfs); else a negative errno value.
1254  *
1255  * This call is synchronous, and may not be used in an interrupt context.
1256  *
1257  * Only the hub driver should ever call this; root hub registration
1258  * uses it indirectly.
1259  */
1260 int usb_new_device(struct usb_device *udev)
1261 {
1262         int err;
1263         int c;
1264
1265         err = usb_get_configuration(udev);
1266         if (err < 0) {
1267                 dev_err(&udev->dev, "can't read configurations, error %d\n",
1268                         err);
1269                 goto fail;
1270         }
1271
1272         /* read the standard strings and cache them if present */
1273         udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
1274         udev->manufacturer = usb_cache_string(udev,
1275                         udev->descriptor.iManufacturer);
1276         udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
1277
1278         /* Tell the world! */
1279         dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
1280                         "SerialNumber=%d\n",
1281                         udev->descriptor.iManufacturer,
1282                         udev->descriptor.iProduct,
1283                         udev->descriptor.iSerialNumber);
1284         show_string(udev, "Product", udev->product);
1285         show_string(udev, "Manufacturer", udev->manufacturer);
1286         show_string(udev, "SerialNumber", udev->serial);
1287
1288 #ifdef  CONFIG_USB_OTG
1289         /*
1290          * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1291          * to wake us after we've powered off VBUS; and HNP, switching roles
1292          * "host" to "peripheral".  The OTG descriptor helps figure this out.
1293          */
1294         if (!udev->bus->is_b_host
1295                         && udev->config
1296                         && udev->parent == udev->bus->root_hub) {
1297                 struct usb_otg_descriptor       *desc = 0;
1298                 struct usb_bus                  *bus = udev->bus;
1299
1300                 /* descriptor may appear anywhere in config */
1301                 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1302                                         le16_to_cpu(udev->config[0].desc.wTotalLength),
1303                                         USB_DT_OTG, (void **) &desc) == 0) {
1304                         if (desc->bmAttributes & USB_OTG_HNP) {
1305                                 unsigned                port1;
1306                                 struct usb_device       *root = udev->parent;
1307                                 
1308                                 for (port1 = 1; port1 <= root->maxchild;
1309                                                 port1++) {
1310                                         if (root->children[port1-1] == udev)
1311                                                 break;
1312                                 }
1313
1314                                 dev_info(&udev->dev,
1315                                         "Dual-Role OTG device on %sHNP port\n",
1316                                         (port1 == bus->otg_port)
1317                                                 ? "" : "non-");
1318
1319                                 /* enable HNP before suspend, it's simpler */
1320                                 if (port1 == bus->otg_port)
1321                                         bus->b_hnp_enable = 1;
1322                                 err = usb_control_msg(udev,
1323                                         usb_sndctrlpipe(udev, 0),
1324                                         USB_REQ_SET_FEATURE, 0,
1325                                         bus->b_hnp_enable
1326                                                 ? USB_DEVICE_B_HNP_ENABLE
1327                                                 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1328                                         0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1329                                 if (err < 0) {
1330                                         /* OTG MESSAGE: report errors here,
1331                                          * customize to match your product.
1332                                          */
1333                                         dev_info(&udev->dev,
1334                                                 "can't set HNP mode; %d\n",
1335                                                 err);
1336                                         bus->b_hnp_enable = 0;
1337                                 }
1338                         }
1339                 }
1340         }
1341
1342         if (!is_targeted(udev)) {
1343
1344                 /* Maybe it can talk to us, though we can't talk to it.
1345                  * (Includes HNP test device.)
1346                  */
1347                 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1348                         static int __usb_suspend_device(struct usb_device *,
1349                                                 int port1);
1350                         err = __usb_suspend_device(udev, udev->bus->otg_port);
1351                         if (err < 0)
1352                                 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1353                 }
1354                 err = -ENODEV;
1355                 goto fail;
1356         }
1357 #endif
1358
1359         /* put device-specific files into sysfs */
1360         err = device_add (&udev->dev);
1361         if (err) {
1362                 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1363                 goto fail;
1364         }
1365         usb_create_sysfs_dev_files (udev);
1366
1367         /* choose and set the configuration. that registers the interfaces
1368          * with the driver core, and lets usb device drivers bind to them.
1369          */
1370         c = choose_configuration(udev);
1371         if (c < 0)
1372                 dev_warn(&udev->dev,
1373                                 "can't choose an initial configuration\n");
1374         else {
1375                 err = usb_set_configuration(udev, c);
1376                 if (err) {
1377                         dev_err(&udev->dev, "can't set config #%d, error %d\n",
1378                                         c, err);
1379                         usb_remove_sysfs_dev_files(udev);
1380                         device_del(&udev->dev);
1381                         goto fail;
1382                 }
1383         }
1384
1385         /* USB device state == configured ... usable */
1386         usb_notify_add_device(udev);
1387
1388         return 0;
1389
1390 fail:
1391         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1392         return err;
1393 }
1394
1395
1396 static int hub_port_status(struct usb_hub *hub, int port1,
1397                                u16 *status, u16 *change)
1398 {
1399         int ret;
1400
1401         ret = get_port_status(hub->hdev, port1, &hub->status->port);
1402         if (ret < 0)
1403                 dev_err (hub->intfdev,
1404                         "%s failed (err = %d)\n", __FUNCTION__, ret);
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 #define PORT_RESET_TRIES        5
1414 #define SET_ADDRESS_TRIES       2
1415 #define GET_DESCRIPTOR_TRIES    2
1416 #define SET_CONFIG_TRIES        (2 * (use_both_schemes + 1))
1417 #define USE_NEW_SCHEME(i)       ((i) / 2 == old_scheme_first)
1418
1419 #define HUB_ROOT_RESET_TIME     50      /* times are in msec */
1420 #define HUB_SHORT_RESET_TIME    10
1421 #define HUB_LONG_RESET_TIME     200
1422 #define HUB_RESET_TIMEOUT       500
1423
1424 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1425                                 struct usb_device *udev, unsigned int delay)
1426 {
1427         int delay_time, ret;
1428         u16 portstatus;
1429         u16 portchange;
1430
1431         for (delay_time = 0;
1432                         delay_time < HUB_RESET_TIMEOUT;
1433                         delay_time += delay) {
1434                 /* wait to give the device a chance to reset */
1435                 msleep(delay);
1436
1437                 /* read and decode port status */
1438                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1439                 if (ret < 0)
1440                         return ret;
1441
1442                 /* Device went away? */
1443                 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1444                         return -ENOTCONN;
1445
1446                 /* bomb out completely if something weird happened */
1447                 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1448                         return -EINVAL;
1449
1450                 /* if we`ve finished resetting, then break out of the loop */
1451                 if (!(portstatus & USB_PORT_STAT_RESET) &&
1452                     (portstatus & USB_PORT_STAT_ENABLE)) {
1453                         if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1454                                 udev->speed = USB_SPEED_HIGH;
1455                         else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1456                                 udev->speed = USB_SPEED_LOW;
1457                         else
1458                                 udev->speed = USB_SPEED_FULL;
1459                         return 0;
1460                 }
1461
1462                 /* switch to the long delay after two short delay failures */
1463                 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
1464                         delay = HUB_LONG_RESET_TIME;
1465
1466                 dev_dbg (hub->intfdev,
1467                         "port %d not reset yet, waiting %dms\n",
1468                         port1, delay);
1469         }
1470
1471         return -EBUSY;
1472 }
1473
1474 static int hub_port_reset(struct usb_hub *hub, int port1,
1475                                 struct usb_device *udev, unsigned int delay)
1476 {
1477         int i, status;
1478
1479         /* Reset the port */
1480         for (i = 0; i < PORT_RESET_TRIES; i++) {
1481                 status = set_port_feature(hub->hdev,
1482                                 port1, USB_PORT_FEAT_RESET);
1483                 if (status)
1484                         dev_err(hub->intfdev,
1485                                         "cannot reset port %d (err = %d)\n",
1486                                         port1, status);
1487                 else {
1488                         status = hub_port_wait_reset(hub, port1, udev, delay);
1489                         if (status && status != -ENOTCONN)
1490                                 dev_dbg(hub->intfdev,
1491                                                 "port_wait_reset: err = %d\n",
1492                                                 status);
1493                 }
1494
1495                 /* return on disconnect or reset */
1496                 switch (status) {
1497                 case 0:
1498                         /* TRSTRCY = 10 ms; plus some extra */
1499                         msleep(10 + 40);
1500                         /* FALL THROUGH */
1501                 case -ENOTCONN:
1502                 case -ENODEV:
1503                         clear_port_feature(hub->hdev,
1504                                 port1, USB_PORT_FEAT_C_RESET);
1505                         /* FIXME need disconnect() for NOTATTACHED device */
1506                         usb_set_device_state(udev, status
1507                                         ? USB_STATE_NOTATTACHED
1508                                         : USB_STATE_DEFAULT);
1509                         return status;
1510                 }
1511
1512                 dev_dbg (hub->intfdev,
1513                         "port %d not enabled, trying reset again...\n",
1514                         port1);
1515                 delay = HUB_LONG_RESET_TIME;
1516         }
1517
1518         dev_err (hub->intfdev,
1519                 "Cannot enable port %i.  Maybe the USB cable is bad?\n",
1520                 port1);
1521
1522         return status;
1523 }
1524
1525 /*
1526  * Disable a port and mark a logical connnect-change event, so that some
1527  * time later khubd will disconnect() any existing usb_device on the port
1528  * and will re-enumerate if there actually is a device attached.
1529  */
1530 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
1531 {
1532         dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
1533         hub_port_disable(hub, port1, 1);
1534
1535         /* FIXME let caller ask to power down the port:
1536          *  - some devices won't enumerate without a VBUS power cycle
1537          *  - SRP saves power that way
1538          *  - ... new call, TBD ...
1539          * That's easy if this hub can switch power per-port, and
1540          * khubd reactivates the port later (timer, SRP, etc).
1541          * Powerdown must be optional, because of reset/DFU.
1542          */
1543
1544         set_bit(port1, hub->change_bits);
1545         kick_khubd(hub);
1546 }
1547
1548
1549 #ifdef  CONFIG_USB_SUSPEND
1550
1551 /*
1552  * Selective port suspend reduces power; most suspended devices draw
1553  * less than 500 uA.  It's also used in OTG, along with remote wakeup.
1554  * All devices below the suspended port are also suspended.
1555  *
1556  * Devices leave suspend state when the host wakes them up.  Some devices
1557  * also support "remote wakeup", where the device can activate the USB
1558  * tree above them to deliver data, such as a keypress or packet.  In
1559  * some cases, this wakes the USB host.
1560  */
1561 static int hub_port_suspend(struct usb_hub *hub, int port1,
1562                 struct usb_device *udev)
1563 {
1564         int     status;
1565
1566         // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
1567
1568         /* enable remote wakeup when appropriate; this lets the device
1569          * wake up the upstream hub (including maybe the root hub).
1570          *
1571          * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
1572          * we don't explicitly enable it here.
1573          */
1574         if (device_may_wakeup(&udev->dev)) {
1575                 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1576                                 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
1577                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1578                                 NULL, 0,
1579                                 USB_CTRL_SET_TIMEOUT);
1580                 if (status)
1581                         dev_dbg(&udev->dev,
1582                                 "won't remote wakeup, status %d\n",
1583                                 status);
1584         }
1585
1586         /* see 7.1.7.6 */
1587         status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
1588         if (status) {
1589                 dev_dbg(hub->intfdev,
1590                         "can't suspend port %d, status %d\n",
1591                         port1, status);
1592                 /* paranoia:  "should not happen" */
1593                 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1594                                 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
1595                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1596                                 NULL, 0,
1597                                 USB_CTRL_SET_TIMEOUT);
1598         } else {
1599                 /* device has up to 10 msec to fully suspend */
1600                 dev_dbg(&udev->dev, "usb suspend\n");
1601                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1602                 msleep(10);
1603         }
1604         return status;
1605 }
1606
1607 /*
1608  * Devices on USB hub ports have only one "suspend" state, corresponding
1609  * to ACPI D2, "may cause the device to lose some context".
1610  * State transitions include:
1611  *
1612  *   - suspend, resume ... when the VBUS power link stays live
1613  *   - suspend, disconnect ... VBUS lost
1614  *
1615  * Once VBUS drop breaks the circuit, the port it's using has to go through
1616  * normal re-enumeration procedures, starting with enabling VBUS power.
1617  * Other than re-initializing the hub (plug/unplug, except for root hubs),
1618  * Linux (2.6) currently has NO mechanisms to initiate that:  no khubd
1619  * timer, no SRP, no requests through sysfs.
1620  *
1621  * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
1622  * the root hub for their bus goes into global suspend ... so we don't
1623  * (falsely) update the device power state to say it suspended.
1624  */
1625 static int __usb_suspend_device (struct usb_device *udev, int port1)
1626 {
1627         int     status = 0;
1628
1629         /* caller owns the udev device lock */
1630         if (port1 < 0)
1631                 return port1;
1632
1633         if (udev->state == USB_STATE_SUSPENDED
1634                         || udev->state == USB_STATE_NOTATTACHED) {
1635                 return 0;
1636         }
1637
1638         /* all interfaces must already be suspended */
1639         if (udev->actconfig) {
1640                 int     i;
1641
1642                 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1643                         struct usb_interface    *intf;
1644
1645                         intf = udev->actconfig->interface[i];
1646                         if (is_active(intf)) {
1647                                 dev_dbg(&intf->dev, "nyet suspended\n");
1648                                 return -EBUSY;
1649                         }
1650                 }
1651         }
1652
1653         /* we only change a device's upstream USB link.
1654          * root hubs have no upstream USB link.
1655          */
1656         if (udev->parent)
1657                 status = hub_port_suspend(hdev_to_hub(udev->parent), port1,
1658                                 udev);
1659
1660         if (status == 0)
1661                 udev->dev.power.power_state = PMSG_SUSPEND;
1662         return status;
1663 }
1664
1665 #endif
1666
1667 /*
1668  * usb_suspend_device - suspend a usb device
1669  * @udev: device that's no longer in active use
1670  * Context: must be able to sleep; device not locked; pm locks held
1671  *
1672  * Suspends a USB device that isn't in active use, conserving power.
1673  * Devices may wake out of a suspend, if anything important happens,
1674  * using the remote wakeup mechanism.  They may also be taken out of
1675  * suspend by the host, using usb_resume_device().  It's also routine
1676  * to disconnect devices while they are suspended.
1677  *
1678  * This only affects the USB hardware for a device; its interfaces
1679  * (and, for hubs, child devices) must already have been suspended.
1680  *
1681  * Suspending OTG devices may trigger HNP, if that's been enabled
1682  * between a pair of dual-role devices.  That will change roles, such
1683  * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
1684  *
1685  * Returns 0 on success, else negative errno.
1686  */
1687 int usb_suspend_device(struct usb_device *udev)
1688 {
1689 #ifdef  CONFIG_USB_SUSPEND
1690         int     port1, status;
1691
1692         port1 = locktree(udev);
1693         if (port1 < 0)
1694                 return port1;
1695
1696         status = __usb_suspend_device(udev, port1);
1697         usb_unlock_device(udev);
1698         return status;
1699 #else
1700         /* NOTE:  udev->state unchanged, it's not lying ... */
1701         udev->dev.power.power_state = PMSG_SUSPEND;
1702         return 0;
1703 #endif
1704 }
1705
1706 /*
1707  * If the USB "suspend" state is in use (rather than "global suspend"),
1708  * many devices will be individually taken out of suspend state using
1709  * special" resume" signaling.  These routines kick in shortly after
1710  * hardware resume signaling is finished, either because of selective
1711  * resume (by host) or remote wakeup (by device) ... now see what changed
1712  * in the tree that's rooted at this device.
1713  */
1714 static int finish_device_resume(struct usb_device *udev)
1715 {
1716         int     status;
1717         u16     devstatus;
1718
1719         /* caller owns the udev device lock */
1720         dev_dbg(&udev->dev, "finish resume\n");
1721
1722         /* usb ch9 identifies four variants of SUSPENDED, based on what
1723          * state the device resumes to.  Linux currently won't see the
1724          * first two on the host side; they'd be inside hub_port_init()
1725          * during many timeouts, but khubd can't suspend until later.
1726          */
1727         usb_set_device_state(udev, udev->actconfig
1728                         ? USB_STATE_CONFIGURED
1729                         : USB_STATE_ADDRESS);
1730
1731         /* 10.5.4.5 says be sure devices in the tree are still there.
1732          * For now let's assume the device didn't go crazy on resume,
1733          * and device drivers will know about any resume quirks.
1734          */
1735         status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
1736         if (status < 0)
1737                 dev_dbg(&udev->dev,
1738                         "gone after usb resume? status %d\n",
1739                         status);
1740         else if (udev->actconfig) {
1741                 unsigned        i;
1742                 int             (*resume)(struct device *);
1743
1744                 le16_to_cpus(&devstatus);
1745                 if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)
1746                                 && udev->parent) {
1747                         status = usb_control_msg(udev,
1748                                         usb_sndctrlpipe(udev, 0),
1749                                         USB_REQ_CLEAR_FEATURE,
1750                                                 USB_RECIP_DEVICE,
1751                                         USB_DEVICE_REMOTE_WAKEUP, 0,
1752                                         NULL, 0,
1753                                         USB_CTRL_SET_TIMEOUT);
1754                         if (status) {
1755                                 dev_dbg(&udev->dev, "disable remote "
1756                                         "wakeup, status %d\n", status);
1757                                 status = 0;
1758                         }
1759                 }
1760
1761                 /* resume interface drivers; if this is a hub, it
1762                  * may have a child resume event to deal with soon
1763                  */
1764                 resume = udev->dev.bus->resume;
1765                 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++)
1766                         (void) resume(&udev->actconfig->interface[i]->dev);
1767                 status = 0;
1768
1769         } else if (udev->devnum <= 0) {
1770                 dev_dbg(&udev->dev, "bogus resume!\n");
1771                 status = -EINVAL;
1772         }
1773         return status;
1774 }
1775
1776 #ifdef  CONFIG_USB_SUSPEND
1777
1778 static int
1779 hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
1780 {
1781         int     status;
1782
1783         // dev_dbg(hub->intfdev, "resume port %d\n", port1);
1784
1785         /* see 7.1.7.7; affects power usage, but not budgeting */
1786         status = clear_port_feature(hub->hdev,
1787                         port1, USB_PORT_FEAT_SUSPEND);
1788         if (status) {
1789                 dev_dbg(hub->intfdev,
1790                         "can't resume port %d, status %d\n",
1791                         port1, status);
1792         } else {
1793                 u16             devstatus;
1794                 u16             portchange;
1795
1796                 /* drive resume for at least 20 msec */
1797                 if (udev)
1798                         dev_dbg(&udev->dev, "RESUME\n");
1799                 msleep(25);
1800
1801 #define LIVE_FLAGS      ( USB_PORT_STAT_POWER \
1802                         | USB_PORT_STAT_ENABLE \
1803                         | USB_PORT_STAT_CONNECTION)
1804
1805                 /* Virtual root hubs can trigger on GET_PORT_STATUS to
1806                  * stop resume signaling.  Then finish the resume
1807                  * sequence.
1808                  */
1809                 devstatus = portchange = 0;
1810                 status = hub_port_status(hub, port1,
1811                                 &devstatus, &portchange);
1812                 if (status < 0
1813                                 || (devstatus & LIVE_FLAGS) != LIVE_FLAGS
1814                                 || (devstatus & USB_PORT_STAT_SUSPEND) != 0
1815                                 ) {
1816                         dev_dbg(hub->intfdev,
1817                                 "port %d status %04x.%04x after resume, %d\n",
1818                                 port1, portchange, devstatus, status);
1819                 } else {
1820                         /* TRSMRCY = 10 msec */
1821                         msleep(10);
1822                         if (udev)
1823                                 status = finish_device_resume(udev);
1824                 }
1825         }
1826         if (status < 0)
1827                 hub_port_logical_disconnect(hub, port1);
1828
1829         return status;
1830 }
1831
1832 #endif
1833
1834 /*
1835  * usb_resume_device - re-activate a suspended usb device
1836  * @udev: device to re-activate
1837  * Context: must be able to sleep; device not locked; pm locks held
1838  *
1839  * This will re-activate the suspended device, increasing power usage
1840  * while letting drivers communicate again with its endpoints.
1841  * USB resume explicitly guarantees that the power session between
1842  * the host and the device is the same as it was when the device
1843  * suspended.
1844  *
1845  * Returns 0 on success, else negative errno.
1846  */
1847 int usb_resume_device(struct usb_device *udev)
1848 {
1849         int     port1, status;
1850
1851         port1 = locktree(udev);
1852         if (port1 < 0)
1853                 return port1;
1854
1855 #ifdef  CONFIG_USB_SUSPEND
1856         /* selective resume of one downstream hub-to-device port */
1857         if (udev->parent) {
1858                 if (udev->state == USB_STATE_SUSPENDED) {
1859                         // NOTE swsusp may bork us, device state being wrong...
1860                         // NOTE this fails if parent is also suspended...
1861                         status = hub_port_resume(hdev_to_hub(udev->parent),
1862                                         port1, udev);
1863                 } else
1864                         status = 0;
1865         } else
1866 #endif
1867                 status = finish_device_resume(udev);
1868         if (status < 0)
1869                 dev_dbg(&udev->dev, "can't resume, status %d\n",
1870                         status);
1871
1872         usb_unlock_device(udev);
1873
1874         /* rebind drivers that had no suspend() */
1875         if (status == 0) {
1876                 usb_lock_all_devices();
1877                 bus_rescan_devices(&usb_bus_type);
1878                 usb_unlock_all_devices();
1879         }
1880         return status;
1881 }
1882
1883 static int remote_wakeup(struct usb_device *udev)
1884 {
1885         int     status = 0;
1886
1887 #ifdef  CONFIG_USB_SUSPEND
1888
1889         /* don't repeat RESUME sequence if this device
1890          * was already woken up by some other task
1891          */
1892         down(&udev->serialize);
1893         if (udev->state == USB_STATE_SUSPENDED) {
1894                 dev_dbg(&udev->dev, "RESUME (wakeup)\n");
1895                 /* TRSMRCY = 10 msec */
1896                 msleep(10);
1897                 status = finish_device_resume(udev);
1898         }
1899         up(&udev->serialize);
1900 #endif
1901         return status;
1902 }
1903
1904 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
1905 {
1906         struct usb_hub          *hub = usb_get_intfdata (intf);
1907         struct usb_device       *hdev = hub->hdev;
1908         unsigned                port1;
1909
1910         /* fail if children aren't already suspended */
1911         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1912                 struct usb_device       *udev;
1913
1914                 udev = hdev->children [port1-1];
1915                 if (udev && (udev->dev.power.power_state.event
1916                                         == PM_EVENT_ON
1917 #ifdef  CONFIG_USB_SUSPEND
1918                                 || udev->state != USB_STATE_SUSPENDED
1919 #endif
1920                                 )) {
1921                         dev_dbg(&intf->dev, "port %d nyet suspended\n", port1);
1922                         return -EBUSY;
1923                 }
1924         }
1925
1926         /* "global suspend" of the downstream HC-to-USB interface */
1927         if (!hdev->parent) {
1928                 struct usb_bus  *bus = hdev->bus;
1929                 if (bus) {
1930                         int     status = hcd_bus_suspend (bus);
1931
1932                         if (status != 0) {
1933                                 dev_dbg(&hdev->dev, "'global' suspend %d\n",
1934                                         status);
1935                                 return status;
1936                         }
1937                 } else
1938                         return -EOPNOTSUPP;
1939         }
1940
1941         /* stop khubd and related activity */
1942         hub_quiesce(hub);
1943         return 0;
1944 }
1945
1946 static int hub_resume(struct usb_interface *intf)
1947 {
1948         struct usb_device       *hdev = interface_to_usbdev(intf);
1949         struct usb_hub          *hub = usb_get_intfdata (intf);
1950         int                     status;
1951
1952         /* "global resume" of the downstream HC-to-USB interface */
1953         if (!hdev->parent) {
1954                 struct usb_bus  *bus = hdev->bus;
1955                 if (bus) {
1956                         status = hcd_bus_resume (bus);
1957                         if (status) {
1958                                 dev_dbg(&intf->dev, "'global' resume %d\n",
1959                                         status);
1960                                 return status;
1961                         }
1962                 } else
1963                         return -EOPNOTSUPP;
1964                 if (status == 0) {
1965                         /* TRSMRCY = 10 msec */
1966                         msleep(10);
1967                 }
1968         }
1969
1970         hub_activate(hub);
1971
1972         /* REVISIT:  this recursion probably shouldn't exist.  Remove
1973          * this code sometime, after retesting with different root and
1974          * external hubs.
1975          */
1976 #ifdef  CONFIG_USB_SUSPEND
1977         {
1978         unsigned                port1;
1979
1980         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1981                 struct usb_device       *udev;
1982                 u16                     portstat, portchange;
1983
1984                 udev = hdev->children [port1-1];
1985                 status = hub_port_status(hub, port1, &portstat, &portchange);
1986                 if (status == 0) {
1987                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
1988                                 clear_port_feature(hdev, port1,
1989                                         USB_PORT_FEAT_C_SUSPEND);
1990                                 portchange &= ~USB_PORT_STAT_C_SUSPEND;
1991                         }
1992
1993                         /* let khubd handle disconnects etc */
1994                         if (portchange)
1995                                 continue;
1996                 }
1997
1998                 if (!udev || status < 0)
1999                         continue;
2000                 down (&udev->serialize);
2001                 if (portstat & USB_PORT_STAT_SUSPEND)
2002                         status = hub_port_resume(hub, port1, udev);
2003                 else {
2004                         status = finish_device_resume(udev);
2005                         if (status < 0) {
2006                                 dev_dbg(&intf->dev, "resume port %d --> %d\n",
2007                                         port1, status);
2008                                 hub_port_logical_disconnect(hub, port1);
2009                         }
2010                 }
2011                 up(&udev->serialize);
2012         }
2013         }
2014 #endif
2015         return 0;
2016 }
2017
2018 void usb_suspend_root_hub(struct usb_device *hdev)
2019 {
2020         struct usb_hub *hub = hdev_to_hub(hdev);
2021
2022         /* This also makes any led blinker stop retriggering.  We're called
2023          * from irq, so the blinker might still be scheduled.  Caller promises
2024          * that the root hub status URB will be canceled.
2025          */
2026         __hub_quiesce(hub);
2027         mark_quiesced(to_usb_interface(hub->intfdev));
2028 }
2029
2030 void usb_resume_root_hub(struct usb_device *hdev)
2031 {
2032         struct usb_hub *hub = hdev_to_hub(hdev);
2033
2034         hub->resume_root_hub = 1;
2035         kick_khubd(hub);
2036 }
2037
2038
2039 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
2040  *
2041  * Between connect detection and reset signaling there must be a delay
2042  * of 100ms at least for debounce and power-settling.  The corresponding
2043  * timer shall restart whenever the downstream port detects a disconnect.
2044  * 
2045  * Apparently there are some bluetooth and irda-dongles and a number of
2046  * low-speed devices for which this debounce period may last over a second.
2047  * Not covered by the spec - but easy to deal with.
2048  *
2049  * This implementation uses a 1500ms total debounce timeout; if the
2050  * connection isn't stable by then it returns -ETIMEDOUT.  It checks
2051  * every 25ms for transient disconnects.  When the port status has been
2052  * unchanged for 100ms it returns the port status.
2053  */
2054
2055 #define HUB_DEBOUNCE_TIMEOUT    1500
2056 #define HUB_DEBOUNCE_STEP         25
2057 #define HUB_DEBOUNCE_STABLE      100
2058
2059 static int hub_port_debounce(struct usb_hub *hub, int port1)
2060 {
2061         int ret;
2062         int total_time, stable_time = 0;
2063         u16 portchange, portstatus;
2064         unsigned connection = 0xffff;
2065
2066         for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
2067                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2068                 if (ret < 0)
2069                         return ret;
2070
2071                 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
2072                      (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2073                         stable_time += HUB_DEBOUNCE_STEP;
2074                         if (stable_time >= HUB_DEBOUNCE_STABLE)
2075                                 break;
2076                 } else {
2077                         stable_time = 0;
2078                         connection = portstatus & USB_PORT_STAT_CONNECTION;
2079                 }
2080
2081                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2082                         clear_port_feature(hub->hdev, port1,
2083                                         USB_PORT_FEAT_C_CONNECTION);
2084                 }
2085
2086                 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2087                         break;
2088                 msleep(HUB_DEBOUNCE_STEP);
2089         }
2090
2091         dev_dbg (hub->intfdev,
2092                 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2093                 port1, total_time, stable_time, portstatus);
2094
2095         if (stable_time < HUB_DEBOUNCE_STABLE)
2096                 return -ETIMEDOUT;
2097         return portstatus;
2098 }
2099
2100 static void ep0_reinit(struct usb_device *udev)
2101 {
2102         usb_disable_endpoint(udev, 0 + USB_DIR_IN);
2103         usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
2104         udev->ep_in[0] = udev->ep_out[0] = &udev->ep0;
2105 }
2106
2107 #define usb_sndaddr0pipe()      (PIPE_CONTROL << 30)
2108 #define usb_rcvaddr0pipe()      ((PIPE_CONTROL << 30) | USB_DIR_IN)
2109
2110 static int hub_set_address(struct usb_device *udev)
2111 {
2112         int retval;
2113
2114         if (udev->devnum == 0)
2115                 return -EINVAL;
2116         if (udev->state == USB_STATE_ADDRESS)
2117                 return 0;
2118         if (udev->state != USB_STATE_DEFAULT)
2119                 return -EINVAL;
2120         retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2121                 USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
2122                 NULL, 0, USB_CTRL_SET_TIMEOUT);
2123         if (retval == 0) {
2124                 usb_set_device_state(udev, USB_STATE_ADDRESS);
2125                 ep0_reinit(udev);
2126         }
2127         return retval;
2128 }
2129
2130 /* Reset device, (re)assign address, get device descriptor.
2131  * Device connection must be stable, no more debouncing needed.
2132  * Returns device in USB_STATE_ADDRESS, except on error.
2133  *
2134  * If this is called for an already-existing device (as part of
2135  * usb_reset_device), the caller must own the device lock.  For a
2136  * newly detected device that is not accessible through any global
2137  * pointers, it's not necessary to lock the device.
2138  */
2139 static int
2140 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2141                 int retry_counter)
2142 {
2143         static DECLARE_MUTEX(usb_address0_sem);
2144
2145         struct usb_device       *hdev = hub->hdev;
2146         int                     i, j, retval;
2147         unsigned                delay = HUB_SHORT_RESET_TIME;
2148         enum usb_device_speed   oldspeed = udev->speed;
2149
2150         /* root hub ports have a slightly longer reset period
2151          * (from USB 2.0 spec, section 7.1.7.5)
2152          */
2153         if (!hdev->parent) {
2154                 delay = HUB_ROOT_RESET_TIME;
2155                 if (port1 == hdev->bus->otg_port)
2156                         hdev->bus->b_hnp_enable = 0;
2157         }
2158
2159         /* Some low speed devices have problems with the quick delay, so */
2160         /*  be a bit pessimistic with those devices. RHbug #23670 */
2161         if (oldspeed == USB_SPEED_LOW)
2162                 delay = HUB_LONG_RESET_TIME;
2163
2164         down(&usb_address0_sem);
2165
2166         /* Reset the device; full speed may morph to high speed */
2167         retval = hub_port_reset(hub, port1, udev, delay);
2168         if (retval < 0)         /* error or disconnect */
2169                 goto fail;
2170                                 /* success, speed is known */
2171         retval = -ENODEV;
2172
2173         if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2174                 dev_dbg(&udev->dev, "device reset changed speed!\n");
2175                 goto fail;
2176         }
2177         oldspeed = udev->speed;
2178   
2179         /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2180          * it's fixed size except for full speed devices.
2181          */
2182         switch (udev->speed) {
2183         case USB_SPEED_HIGH:            /* fixed at 64 */
2184                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2185                 break;
2186         case USB_SPEED_FULL:            /* 8, 16, 32, or 64 */
2187                 /* to determine the ep0 maxpacket size, try to read
2188                  * the device descriptor to get bMaxPacketSize0 and
2189                  * then correct our initial guess.
2190                  */
2191                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2192                 break;
2193         case USB_SPEED_LOW:             /* fixed at 8 */
2194                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
2195                 break;
2196         default:
2197                 goto fail;
2198         }
2199  
2200         dev_info (&udev->dev,
2201                         "%s %s speed USB device using %s and address %d\n",
2202                         (udev->config) ? "reset" : "new",
2203                         ({ char *speed; switch (udev->speed) {
2204                         case USB_SPEED_LOW:     speed = "low";  break;
2205                         case USB_SPEED_FULL:    speed = "full"; break;
2206                         case USB_SPEED_HIGH:    speed = "high"; break;
2207                         default:                speed = "?";    break;
2208                         }; speed;}),
2209                         udev->bus->controller->driver->name,
2210                         udev->devnum);
2211
2212         /* Set up TT records, if needed  */
2213         if (hdev->tt) {
2214                 udev->tt = hdev->tt;
2215                 udev->ttport = hdev->ttport;
2216         } else if (udev->speed != USB_SPEED_HIGH
2217                         && hdev->speed == USB_SPEED_HIGH) {
2218                 udev->tt = &hub->tt;
2219                 udev->ttport = port1;
2220         }
2221  
2222         /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2223          * Because device hardware and firmware is sometimes buggy in
2224          * this area, and this is how Linux has done it for ages.
2225          * Change it cautiously.
2226          *
2227          * NOTE:  If USE_NEW_SCHEME() is true we will start by issuing
2228          * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
2229          * so it may help with some non-standards-compliant devices.
2230          * Otherwise we start with SET_ADDRESS and then try to read the
2231          * first 8 bytes of the device descriptor to get the ep0 maxpacket
2232          * value.
2233          */
2234         for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2235                 if (USE_NEW_SCHEME(retry_counter)) {
2236                         struct usb_device_descriptor *buf;
2237                         int r = 0;
2238
2239 #define GET_DESCRIPTOR_BUFSIZE  64
2240                         buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2241                         if (!buf) {
2242                                 retval = -ENOMEM;
2243                                 continue;
2244                         }
2245
2246                         /* Use a short timeout the first time through,
2247                          * so that recalcitrant full-speed devices with
2248                          * 8- or 16-byte ep0-maxpackets won't slow things
2249                          * down tremendously by NAKing the unexpectedly
2250                          * early status stage.  Also, retry on all errors;
2251                          * some devices are flakey.
2252                          */
2253                         for (j = 0; j < 3; ++j) {
2254                                 buf->bMaxPacketSize0 = 0;
2255                                 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2256                                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2257                                         USB_DT_DEVICE << 8, 0,
2258                                         buf, GET_DESCRIPTOR_BUFSIZE,
2259                                         (i ? USB_CTRL_GET_TIMEOUT : 1000));
2260                                 switch (buf->bMaxPacketSize0) {
2261                                 case 8: case 16: case 32: case 64:
2262                                         if (buf->bDescriptorType ==
2263                                                         USB_DT_DEVICE) {
2264                                                 r = 0;
2265                                                 break;
2266                                         }
2267                                         /* FALL THROUGH */
2268                                 default:
2269                                         if (r == 0)
2270                                                 r = -EPROTO;
2271                                         break;
2272                                 }
2273                                 if (r == 0)
2274                                         break;
2275                         }
2276                         udev->descriptor.bMaxPacketSize0 =
2277                                         buf->bMaxPacketSize0;
2278                         kfree(buf);
2279
2280                         retval = hub_port_reset(hub, port1, udev, delay);
2281                         if (retval < 0)         /* error or disconnect */
2282                                 goto fail;
2283                         if (oldspeed != udev->speed) {
2284                                 dev_dbg(&udev->dev,
2285                                         "device reset changed speed!\n");
2286                                 retval = -ENODEV;
2287                                 goto fail;
2288                         }
2289                         if (r) {
2290                                 dev_err(&udev->dev, "device descriptor "
2291                                                 "read/%s, error %d\n",
2292                                                 "64", r);
2293                                 retval = -EMSGSIZE;
2294                                 continue;
2295                         }
2296 #undef GET_DESCRIPTOR_BUFSIZE
2297                 }
2298
2299                 for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2300                         retval = hub_set_address(udev);
2301                         if (retval >= 0)
2302                                 break;
2303                         msleep(200);
2304                 }
2305                 if (retval < 0) {
2306                         dev_err(&udev->dev,
2307                                 "device not accepting address %d, error %d\n",
2308                                 udev->devnum, retval);
2309                         goto fail;
2310                 }
2311  
2312                 /* cope with hardware quirkiness:
2313                  *  - let SET_ADDRESS settle, some device hardware wants it
2314                  *  - read ep0 maxpacket even for high and low speed,
2315                  */
2316                 msleep(10);
2317                 if (USE_NEW_SCHEME(retry_counter))
2318                         break;
2319
2320                 retval = usb_get_device_descriptor(udev, 8);
2321                 if (retval < 8) {
2322                         dev_err(&udev->dev, "device descriptor "
2323                                         "read/%s, error %d\n",
2324                                         "8", retval);
2325                         if (retval >= 0)
2326                                 retval = -EMSGSIZE;
2327                 } else {
2328                         retval = 0;
2329                         break;
2330                 }
2331         }
2332         if (retval)
2333                 goto fail;
2334
2335         i = udev->descriptor.bMaxPacketSize0;
2336         if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2337                 if (udev->speed != USB_SPEED_FULL ||
2338                                 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2339                         dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
2340                         retval = -EMSGSIZE;
2341                         goto fail;
2342                 }
2343                 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2344                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2345                 ep0_reinit(udev);
2346         }
2347   
2348         retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2349         if (retval < (signed)sizeof(udev->descriptor)) {
2350                 dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
2351                         "all", retval);
2352                 if (retval >= 0)
2353                         retval = -ENOMSG;
2354                 goto fail;
2355         }
2356
2357         retval = 0;
2358
2359 fail:
2360         if (retval)
2361                 hub_port_disable(hub, port1, 0);
2362         up(&usb_address0_sem);
2363         return retval;
2364 }
2365
2366 static void
2367 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2368 {
2369         struct usb_qualifier_descriptor *qual;
2370         int                             status;
2371
2372         qual = kmalloc (sizeof *qual, SLAB_KERNEL);
2373         if (qual == NULL)
2374                 return;
2375
2376         status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2377                         qual, sizeof *qual);
2378         if (status == sizeof *qual) {
2379                 dev_info(&udev->dev, "not running at top speed; "
2380                         "connect to a high speed hub\n");
2381                 /* hub LEDs are probably harder to miss than syslog */
2382                 if (hub->has_indicators) {
2383                         hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2384                         schedule_work (&hub->leds);
2385                 }
2386         }
2387         kfree(qual);
2388 }
2389
2390 static unsigned
2391 hub_power_remaining (struct usb_hub *hub)
2392 {
2393         struct usb_device *hdev = hub->hdev;
2394         int remaining;
2395         unsigned i;
2396
2397         remaining = hub->power_budget;
2398         if (!remaining)         /* self-powered */
2399                 return 0;
2400
2401         for (i = 0; i < hdev->maxchild; i++) {
2402                 struct usb_device       *udev = hdev->children[i];
2403                 int                     delta, ceiling;
2404
2405                 if (!udev)
2406                         continue;
2407
2408                 /* 100mA per-port ceiling, or 8mA for OTG ports */
2409                 if (i != (udev->bus->otg_port - 1) || hdev->parent)
2410                         ceiling = 50;
2411                 else
2412                         ceiling = 4;
2413
2414                 if (udev->actconfig)
2415                         delta = udev->actconfig->desc.bMaxPower;
2416                 else
2417                         delta = ceiling;
2418                 // dev_dbg(&udev->dev, "budgeted %dmA\n", 2 * delta);
2419                 if (delta > ceiling)
2420                         dev_warn(&udev->dev, "%dmA over %dmA budget!\n",
2421                                 2 * (delta - ceiling), 2 * ceiling);
2422                 remaining -= delta;
2423         }
2424         if (remaining < 0) {
2425                 dev_warn(hub->intfdev,
2426                         "%dmA over power budget!\n",
2427                         -2 * remaining);
2428                 remaining = 0;
2429         }
2430         return remaining;
2431 }
2432
2433 /* Handle physical or logical connection change events.
2434  * This routine is called when:
2435  *      a port connection-change occurs;
2436  *      a port enable-change occurs (often caused by EMI);
2437  *      usb_reset_device() encounters changed descriptors (as from
2438  *              a firmware download)
2439  * caller already locked the hub
2440  */
2441 static void hub_port_connect_change(struct usb_hub *hub, int port1,
2442                                         u16 portstatus, u16 portchange)
2443 {
2444         struct usb_device *hdev = hub->hdev;
2445         struct device *hub_dev = hub->intfdev;
2446         u16 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
2447         int status, i;
2448  
2449         dev_dbg (hub_dev,
2450                 "port %d, status %04x, change %04x, %s\n",
2451                 port1, portstatus, portchange, portspeed (portstatus));
2452
2453         if (hub->has_indicators) {
2454                 set_port_led(hub, port1, HUB_LED_AUTO);
2455                 hub->indicator[port1-1] = INDICATOR_AUTO;
2456         }
2457  
2458         /* Disconnect any existing devices under this port */
2459         if (hdev->children[port1-1])
2460                 usb_disconnect(&hdev->children[port1-1]);
2461         clear_bit(port1, hub->change_bits);
2462
2463 #ifdef  CONFIG_USB_OTG
2464         /* during HNP, don't repeat the debounce */
2465         if (hdev->bus->is_b_host)
2466                 portchange &= ~USB_PORT_STAT_C_CONNECTION;
2467 #endif
2468
2469         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2470                 status = hub_port_debounce(hub, port1);
2471                 if (status < 0) {
2472                         dev_err (hub_dev,
2473                                 "connect-debounce failed, port %d disabled\n",
2474                                 port1);
2475                         goto done;
2476                 }
2477                 portstatus = status;
2478         }
2479
2480         /* Return now if nothing is connected */
2481         if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2482
2483                 /* maybe switch power back on (e.g. root hub was reset) */
2484                 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2
2485                                 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
2486                         set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
2487  
2488                 if (portstatus & USB_PORT_STAT_ENABLE)
2489                         goto done;
2490                 return;
2491         }
2492
2493 #ifdef  CONFIG_USB_SUSPEND
2494         /* If something is connected, but the port is suspended, wake it up. */
2495         if (portstatus & USB_PORT_STAT_SUSPEND) {
2496                 status = hub_port_resume(hub, port1, NULL);
2497                 if (status < 0) {
2498                         dev_dbg(hub_dev,
2499                                 "can't clear suspend on port %d; %d\n",
2500                                 port1, status);
2501                         goto done;
2502                 }
2503         }
2504 #endif
2505
2506         for (i = 0; i < SET_CONFIG_TRIES; i++) {
2507                 struct usb_device *udev;
2508
2509                 /* reallocate for each attempt, since references
2510                  * to the previous one can escape in various ways
2511                  */
2512                 udev = usb_alloc_dev(hdev, hdev->bus, port1);
2513                 if (!udev) {
2514                         dev_err (hub_dev,
2515                                 "couldn't allocate port %d usb_device\n",
2516                                 port1);
2517                         goto done;
2518                 }
2519
2520                 usb_set_device_state(udev, USB_STATE_POWERED);
2521                 udev->speed = USB_SPEED_UNKNOWN;
2522  
2523                 /* set the address */
2524                 choose_address(udev);
2525                 if (udev->devnum <= 0) {
2526                         status = -ENOTCONN;     /* Don't retry */
2527                         goto loop;
2528                 }
2529
2530                 /* reset and get descriptor */
2531                 status = hub_port_init(hub, udev, port1, i);
2532                 if (status < 0)
2533                         goto loop;
2534
2535                 /* consecutive bus-powered hubs aren't reliable; they can
2536                  * violate the voltage drop budget.  if the new child has
2537                  * a "powered" LED, users should notice we didn't enable it
2538                  * (without reading syslog), even without per-port LEDs
2539                  * on the parent.
2540                  */
2541                 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
2542                                 && hub->power_budget) {
2543                         u16     devstat;
2544
2545                         status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
2546                                         &devstat);
2547                         if (status < 0) {
2548                                 dev_dbg(&udev->dev, "get status %d ?\n", status);
2549                                 goto loop_disable;
2550                         }
2551                         cpu_to_le16s(&devstat);
2552                         if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
2553                                 dev_err(&udev->dev,
2554                                         "can't connect bus-powered hub "
2555                                         "to this port\n");
2556                                 if (hub->has_indicators) {
2557                                         hub->indicator[port1-1] =
2558                                                 INDICATOR_AMBER_BLINK;
2559                                         schedule_work (&hub->leds);
2560                                 }
2561                                 status = -ENOTCONN;     /* Don't retry */
2562                                 goto loop_disable;
2563                         }
2564                 }
2565  
2566                 /* check for devices running slower than they could */
2567                 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
2568                                 && udev->speed == USB_SPEED_FULL
2569                                 && highspeed_hubs != 0)
2570                         check_highspeed (hub, udev, port1);
2571
2572                 /* Store the parent's children[] pointer.  At this point
2573                  * udev becomes globally accessible, although presumably
2574                  * no one will look at it until hdev is unlocked.
2575                  */
2576                 down (&udev->serialize);
2577                 status = 0;
2578
2579                 /* We mustn't add new devices if the parent hub has
2580                  * been disconnected; we would race with the
2581                  * recursively_mark_NOTATTACHED() routine.
2582                  */
2583                 spin_lock_irq(&device_state_lock);
2584                 if (hdev->state == USB_STATE_NOTATTACHED)
2585                         status = -ENOTCONN;
2586                 else
2587                         hdev->children[port1-1] = udev;
2588                 spin_unlock_irq(&device_state_lock);
2589
2590                 /* Run it through the hoops (find a driver, etc) */
2591                 if (!status) {
2592                         status = usb_new_device(udev);
2593                         if (status) {
2594                                 spin_lock_irq(&device_state_lock);
2595                                 hdev->children[port1-1] = NULL;
2596                                 spin_unlock_irq(&device_state_lock);
2597                         }
2598                 }
2599
2600                 up (&udev->serialize);
2601                 if (status)
2602                         goto loop_disable;
2603
2604                 status = hub_power_remaining(hub);
2605                 if (status)
2606                         dev_dbg(hub_dev,
2607                                 "%dmA power budget left\n",
2608                                 2 * status);
2609
2610                 return;
2611
2612 loop_disable:
2613                 hub_port_disable(hub, port1, 1);
2614 loop:
2615                 ep0_reinit(udev);
2616                 release_address(udev);
2617                 usb_put_dev(udev);
2618                 if (status == -ENOTCONN)
2619                         break;
2620         }
2621  
2622 done:
2623         hub_port_disable(hub, port1, 1);
2624 }
2625
2626 static void hub_events(void)
2627 {
2628         struct list_head *tmp;
2629         struct usb_device *hdev;
2630         struct usb_interface *intf;
2631         struct usb_hub *hub;
2632         struct device *hub_dev;
2633         u16 hubstatus;
2634         u16 hubchange;
2635         u16 portstatus;
2636         u16 portchange;
2637         int i, ret;
2638         int connect_change;
2639
2640         /*
2641          *  We restart the list every time to avoid a deadlock with
2642          * deleting hubs downstream from this one. This should be
2643          * safe since we delete the hub from the event list.
2644          * Not the most efficient, but avoids deadlocks.
2645          */
2646         while (1) {
2647
2648                 /* Grab the first entry at the beginning of the list */
2649                 spin_lock_irq(&hub_event_lock);
2650                 if (list_empty(&hub_event_list)) {
2651                         spin_unlock_irq(&hub_event_lock);
2652                         break;
2653                 }
2654
2655                 tmp = hub_event_list.next;
2656                 list_del_init(tmp);
2657
2658                 hub = list_entry(tmp, struct usb_hub, event_list);
2659                 hdev = hub->hdev;
2660                 intf = to_usb_interface(hub->intfdev);
2661                 hub_dev = &intf->dev;
2662
2663                 i = hub->resume_root_hub;
2664
2665                 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x%s\n",
2666                                 hdev->state, hub->descriptor
2667                                         ? hub->descriptor->bNbrPorts
2668                                         : 0,
2669                                 /* NOTE: expects max 15 ports... */
2670                                 (u16) hub->change_bits[0],
2671                                 (u16) hub->event_bits[0],
2672                                 i ? ", resume root" : "");
2673
2674                 usb_get_intf(intf);
2675                 spin_unlock_irq(&hub_event_lock);
2676
2677                 /* Is this is a root hub wanting to reactivate the downstream
2678                  * ports?  If so, be sure the interface resumes even if its
2679                  * stub "device" node was never suspended.
2680                  */
2681                 if (i) {
2682                         dpm_runtime_resume(&hdev->dev);
2683                         dpm_runtime_resume(&intf->dev);
2684                 }
2685
2686                 /* Lock the device, then check to see if we were
2687                  * disconnected while waiting for the lock to succeed. */
2688                 if (locktree(hdev) < 0) {
2689                         usb_put_intf(intf);
2690                         continue;
2691                 }
2692                 if (hub != usb_get_intfdata(intf))
2693                         goto loop;
2694
2695                 /* If the hub has died, clean up after it */
2696                 if (hdev->state == USB_STATE_NOTATTACHED) {
2697                         hub_pre_reset(hub);
2698                         goto loop;
2699                 }
2700
2701                 /* If this is an inactive or suspended hub, do nothing */
2702                 if (hub->quiescing)
2703                         goto loop;
2704
2705                 if (hub->error) {
2706                         dev_dbg (hub_dev, "resetting for error %d\n",
2707                                 hub->error);
2708
2709                         ret = usb_reset_device(hdev);
2710                         if (ret) {
2711                                 dev_dbg (hub_dev,
2712                                         "error resetting hub: %d\n", ret);
2713                                 goto loop;
2714                         }
2715
2716                         hub->nerrors = 0;
2717                         hub->error = 0;
2718                 }
2719
2720                 /* deal with port status changes */
2721                 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
2722                         if (test_bit(i, hub->busy_bits))
2723                                 continue;
2724                         connect_change = test_bit(i, hub->change_bits);
2725                         if (!test_and_clear_bit(i, hub->event_bits) &&
2726                                         !connect_change && !hub->activating)
2727                                 continue;
2728
2729                         ret = hub_port_status(hub, i,
2730                                         &portstatus, &portchange);
2731                         if (ret < 0)
2732                                 continue;
2733
2734                         if (hub->activating && !hdev->children[i-1] &&
2735                                         (portstatus &
2736                                                 USB_PORT_STAT_CONNECTION))
2737                                 connect_change = 1;
2738
2739                         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2740                                 clear_port_feature(hdev, i,
2741                                         USB_PORT_FEAT_C_CONNECTION);
2742                                 connect_change = 1;
2743                         }
2744
2745                         if (portchange & USB_PORT_STAT_C_ENABLE) {
2746                                 if (!connect_change)
2747                                         dev_dbg (hub_dev,
2748                                                 "port %d enable change, "
2749                                                 "status %08x\n",
2750                                                 i, portstatus);
2751                                 clear_port_feature(hdev, i,
2752                                         USB_PORT_FEAT_C_ENABLE);
2753
2754                                 /*
2755                                  * EM interference sometimes causes badly
2756                                  * shielded USB devices to be shutdown by
2757                                  * the hub, this hack enables them again.
2758                                  * Works at least with mouse driver. 
2759                                  */
2760                                 if (!(portstatus & USB_PORT_STAT_ENABLE)
2761                                     && !connect_change
2762                                     && hdev->children[i-1]) {
2763                                         dev_err (hub_dev,
2764                                             "port %i "
2765                                             "disabled by hub (EMI?), "
2766                                             "re-enabling...\n",
2767                                                 i);
2768                                         connect_change = 1;
2769                                 }
2770                         }
2771
2772                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
2773                                 clear_port_feature(hdev, i,
2774                                         USB_PORT_FEAT_C_SUSPEND);
2775                                 if (hdev->children[i-1]) {
2776                                         ret = remote_wakeup(hdev->
2777                                                         children[i-1]);
2778                                         if (ret < 0)
2779                                                 connect_change = 1;
2780                                 } else {
2781                                         ret = -ENODEV;
2782                                         hub_port_disable(hub, i, 1);
2783                                 }
2784                                 dev_dbg (hub_dev,
2785                                         "resume on port %d, status %d\n",
2786                                         i, ret);
2787                         }
2788                         
2789                         if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
2790                                 dev_err (hub_dev,
2791                                         "over-current change on port %d\n",
2792                                         i);
2793                                 clear_port_feature(hdev, i,
2794                                         USB_PORT_FEAT_C_OVER_CURRENT);
2795                                 hub_power_on(hub);
2796                         }
2797
2798                         if (portchange & USB_PORT_STAT_C_RESET) {
2799                                 dev_dbg (hub_dev,
2800                                         "reset change on port %d\n",
2801                                         i);
2802                                 clear_port_feature(hdev, i,
2803                                         USB_PORT_FEAT_C_RESET);
2804                         }
2805
2806                         if (connect_change)
2807                                 hub_port_connect_change(hub, i,
2808                                                 portstatus, portchange);
2809                 } /* end for i */
2810
2811                 /* deal with hub status changes */
2812                 if (test_and_clear_bit(0, hub->event_bits) == 0)
2813                         ;       /* do nothing */
2814                 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
2815                         dev_err (hub_dev, "get_hub_status failed\n");
2816                 else {
2817                         if (hubchange & HUB_CHANGE_LOCAL_POWER) {
2818                                 dev_dbg (hub_dev, "power change\n");
2819                                 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
2820                         }
2821                         if (hubchange & HUB_CHANGE_OVERCURRENT) {
2822                                 dev_dbg (hub_dev, "overcurrent change\n");
2823                                 msleep(500);    /* Cool down */
2824                                 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
2825                                 hub_power_on(hub);
2826                         }
2827                 }
2828
2829                 hub->activating = 0;
2830
2831                 /* If this is a root hub, tell the HCD it's okay to
2832                  * re-enable port-change interrupts now. */
2833                 if (!hdev->parent)
2834                         usb_enable_root_hub_irq(hdev->bus);
2835
2836 loop:
2837                 usb_unlock_device(hdev);
2838                 usb_put_intf(intf);
2839
2840         } /* end while (1) */
2841 }
2842
2843 static int hub_thread(void *__unused)
2844 {
2845         do {
2846                 hub_events();
2847                 wait_event_interruptible(khubd_wait,
2848                                 !list_empty(&hub_event_list) ||
2849                                 kthread_should_stop());
2850                 try_to_freeze();
2851         } while (!kthread_should_stop() || !list_empty(&hub_event_list));
2852
2853         pr_debug("%s: khubd exiting\n", usbcore_name);
2854         return 0;
2855 }
2856
2857 static struct usb_device_id hub_id_table [] = {
2858     { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
2859       .bDeviceClass = USB_CLASS_HUB},
2860     { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
2861       .bInterfaceClass = USB_CLASS_HUB},
2862     { }                                         /* Terminating entry */
2863 };
2864
2865 MODULE_DEVICE_TABLE (usb, hub_id_table);
2866
2867 static struct usb_driver hub_driver = {
2868         .name =         "hub",
2869         .probe =        hub_probe,
2870         .disconnect =   hub_disconnect,
2871         .suspend =      hub_suspend,
2872         .resume =       hub_resume,
2873         .ioctl =        hub_ioctl,
2874         .id_table =     hub_id_table,
2875 };
2876
2877 int usb_hub_init(void)
2878 {
2879         if (usb_register(&hub_driver) < 0) {
2880                 printk(KERN_ERR "%s: can't register hub driver\n",
2881                         usbcore_name);
2882                 return -1;
2883         }
2884
2885         khubd_task = kthread_run(hub_thread, NULL, "khubd");
2886         if (!IS_ERR(khubd_task))
2887                 return 0;
2888
2889         /* Fall through if kernel_thread failed */
2890         usb_deregister(&hub_driver);
2891         printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
2892
2893         return -1;
2894 }
2895
2896 void usb_hub_cleanup(void)
2897 {
2898         kthread_stop(khubd_task);
2899
2900         /*
2901          * Hub resources are freed for us by usb_deregister. It calls
2902          * usb_driver_purge on every device which in turn calls that
2903          * devices disconnect function if it is using this driver.
2904          * The hub_disconnect function takes care of releasing the
2905          * individual hub resources. -greg
2906          */
2907         usb_deregister(&hub_driver);
2908 } /* usb_hub_cleanup() */
2909
2910 static int config_descriptors_changed(struct usb_device *udev)
2911 {
2912         unsigned                        index;
2913         unsigned                        len = 0;
2914         struct usb_config_descriptor    *buf;
2915
2916         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2917                 if (len < le16_to_cpu(udev->config[index].desc.wTotalLength))
2918                         len = le16_to_cpu(udev->config[index].desc.wTotalLength);
2919         }
2920         buf = kmalloc (len, SLAB_KERNEL);
2921         if (buf == NULL) {
2922                 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
2923                 /* assume the worst */
2924                 return 1;
2925         }
2926         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2927                 int length;
2928                 int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
2929
2930                 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
2931                                 old_length);
2932                 if (length < old_length) {
2933                         dev_dbg(&udev->dev, "config index %d, error %d\n",
2934                                         index, length);
2935                         break;
2936                 }
2937                 if (memcmp (buf, udev->rawdescriptors[index], old_length)
2938                                 != 0) {
2939                         dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
2940                                 index, buf->bConfigurationValue);
2941                         break;
2942                 }
2943         }
2944         kfree(buf);
2945         return index != udev->descriptor.bNumConfigurations;
2946 }
2947
2948 /**
2949  * usb_reset_device - perform a USB port reset to reinitialize a device
2950  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2951  *
2952  * WARNING - don't reset any device unless drivers for all of its
2953  * interfaces are expecting that reset!  Maybe some driver->reset()
2954  * method should eventually help ensure sufficient cooperation.
2955  *
2956  * Do a port reset, reassign the device's address, and establish its
2957  * former operating configuration.  If the reset fails, or the device's
2958  * descriptors change from their values before the reset, or the original
2959  * configuration and altsettings cannot be restored, a flag will be set
2960  * telling khubd to pretend the device has been disconnected and then
2961  * re-connected.  All drivers will be unbound, and the device will be
2962  * re-enumerated and probed all over again.
2963  *
2964  * Returns 0 if the reset succeeded, -ENODEV if the device has been
2965  * flagged for logical disconnection, or some other negative error code
2966  * if the reset wasn't even attempted.
2967  *
2968  * The caller must own the device lock.  For example, it's safe to use
2969  * this from a driver probe() routine after downloading new firmware.
2970  * For calls that might not occur during probe(), drivers should lock
2971  * the device using usb_lock_device_for_reset().
2972  */
2973 int usb_reset_device(struct usb_device *udev)
2974 {
2975         struct usb_device               *parent_hdev = udev->parent;
2976         struct usb_hub                  *parent_hub;
2977         struct usb_device_descriptor    descriptor = udev->descriptor;
2978         struct usb_hub                  *hub = NULL;
2979         int                             i, ret = 0, port1 = -1;
2980
2981         if (udev->state == USB_STATE_NOTATTACHED ||
2982                         udev->state == USB_STATE_SUSPENDED) {
2983                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
2984                                 udev->state);
2985                 return -EINVAL;
2986         }
2987
2988         if (!parent_hdev) {
2989                 /* this requires hcd-specific logic; see OHCI hc_restart() */
2990                 dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
2991                 return -EISDIR;
2992         }
2993
2994         for (i = 0; i < parent_hdev->maxchild; i++)
2995                 if (parent_hdev->children[i] == udev) {
2996                         port1 = i + 1;
2997                         break;
2998                 }
2999
3000         if (port1 < 0) {
3001                 /* If this ever happens, it's very bad */
3002                 dev_err(&udev->dev, "Can't locate device's port!\n");
3003                 return -ENOENT;
3004         }
3005         parent_hub = hdev_to_hub(parent_hdev);
3006
3007         /* If we're resetting an active hub, take some special actions */
3008         if (udev->actconfig &&
3009                         udev->actconfig->interface[0]->dev.driver ==
3010                                 &hub_driver.driver &&
3011                         (hub = hdev_to_hub(udev)) != NULL) {
3012                 hub_pre_reset(hub);
3013         }
3014
3015         set_bit(port1, parent_hub->busy_bits);
3016         for (i = 0; i < SET_CONFIG_TRIES; ++i) {
3017
3018                 /* ep0 maxpacket size may change; let the HCD know about it.
3019                  * Other endpoints will be handled by re-enumeration. */
3020                 ep0_reinit(udev);
3021                 ret = hub_port_init(parent_hub, udev, port1, i);
3022                 if (ret >= 0)
3023                         break;
3024         }
3025         clear_bit(port1, parent_hub->busy_bits);
3026         if (ret < 0)
3027                 goto re_enumerate;
3028  
3029         /* Device might have changed firmware (DFU or similar) */
3030         if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
3031                         || config_descriptors_changed (udev)) {
3032                 dev_info(&udev->dev, "device firmware changed\n");
3033                 udev->descriptor = descriptor;  /* for disconnect() calls */
3034                 goto re_enumerate;
3035         }
3036   
3037         if (!udev->actconfig)
3038                 goto done;
3039
3040         ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3041                         USB_REQ_SET_CONFIGURATION, 0,
3042                         udev->actconfig->desc.bConfigurationValue, 0,
3043                         NULL, 0, USB_CTRL_SET_TIMEOUT);
3044         if (ret < 0) {
3045                 dev_err(&udev->dev,
3046                         "can't restore configuration #%d (error=%d)\n",
3047                         udev->actconfig->desc.bConfigurationValue, ret);
3048                 goto re_enumerate;
3049         }
3050         usb_set_device_state(udev, USB_STATE_CONFIGURED);
3051
3052         for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
3053                 struct usb_interface *intf = udev->actconfig->interface[i];
3054                 struct usb_interface_descriptor *desc;
3055
3056                 /* set_interface resets host side toggle even
3057                  * for altsetting zero.  the interface may have no driver.
3058                  */
3059                 desc = &intf->cur_altsetting->desc;
3060                 ret = usb_set_interface(udev, desc->bInterfaceNumber,
3061                         desc->bAlternateSetting);
3062                 if (ret < 0) {
3063                         dev_err(&udev->dev, "failed to restore interface %d "
3064                                 "altsetting %d (error=%d)\n",
3065                                 desc->bInterfaceNumber,
3066                                 desc->bAlternateSetting,
3067                                 ret);
3068                         goto re_enumerate;
3069                 }
3070         }
3071
3072 done:
3073         if (hub)
3074                 hub_post_reset(hub);
3075         return 0;
3076  
3077 re_enumerate:
3078         hub_port_logical_disconnect(parent_hub, port1);
3079         return -ENODEV;
3080 }