[PATCH] USB: add notifier functions to the USB core for devices and busses
[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 #ifdef CONFIG_USB_DEBUG
13         #define DEBUG
14 #else
15         #undef DEBUG
16 #endif
17 #include <linux/kernel.h>
18 #include <linux/errno.h>
19 #include <linux/module.h>
20 #include <linux/moduleparam.h>
21 #include <linux/completion.h>
22 #include <linux/sched.h>
23 #include <linux/list.h>
24 #include <linux/slab.h>
25 #include <linux/smp_lock.h>
26 #include <linux/ioctl.h>
27 #include <linux/usb.h>
28 #include <linux/usbdevice_fs.h>
29 #include <linux/kthread.h>
30
31 #include <asm/semaphore.h>
32 #include <asm/uaccess.h>
33 #include <asm/byteorder.h>
34
35 #include "usb.h"
36 #include "hcd.h"
37 #include "hub.h"
38
39 /* Protect struct usb_device->state and ->children members
40  * Note: Both are also protected by ->serialize, except that ->state can
41  * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
42 static DEFINE_SPINLOCK(device_state_lock);
43
44 /* khubd's worklist and its lock */
45 static DEFINE_SPINLOCK(hub_event_lock);
46 static LIST_HEAD(hub_event_list);       /* List of hubs needing servicing */
47
48 /* Wakes up khubd */
49 static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
50
51 static struct task_struct *khubd_task;
52
53 /* cycle leds on hubs that aren't blinking for attention */
54 static int blinkenlights = 0;
55 module_param (blinkenlights, bool, S_IRUGO);
56 MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
57
58 /*
59  * As of 2.6.10 we introduce a new USB device initialization scheme which
60  * closely resembles the way Windows works.  Hopefully it will be compatible
61  * with a wider range of devices than the old scheme.  However some previously
62  * working devices may start giving rise to "device not accepting address"
63  * errors; if that happens the user can try the old scheme by adjusting the
64  * following module parameters.
65  *
66  * For maximum flexibility there are two boolean parameters to control the
67  * hub driver's behavior.  On the first initialization attempt, if the
68  * "old_scheme_first" parameter is set then the old scheme will be used,
69  * otherwise the new scheme is used.  If that fails and "use_both_schemes"
70  * is set, then the driver will make another attempt, using the other scheme.
71  */
72 static int old_scheme_first = 0;
73 module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
74 MODULE_PARM_DESC(old_scheme_first,
75                  "start with the old device initialization scheme");
76
77 static int use_both_schemes = 1;
78 module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
79 MODULE_PARM_DESC(use_both_schemes,
80                 "try the other device initialization scheme if the "
81                 "first one fails");
82
83
84 #ifdef  DEBUG
85 static inline char *portspeed (int portstatus)
86 {
87         if (portstatus & (1 << USB_PORT_FEAT_HIGHSPEED))
88                 return "480 Mb/s";
89         else if (portstatus & (1 << USB_PORT_FEAT_LOWSPEED))
90                 return "1.5 Mb/s";
91         else
92                 return "12 Mb/s";
93 }
94 #endif
95
96 /* Note that hdev or one of its children must be locked! */
97 static inline struct usb_hub *hdev_to_hub(struct usb_device *hdev)
98 {
99         return usb_get_intfdata(hdev->actconfig->interface[0]);
100 }
101
102 /* USB 2.0 spec Section 11.24.4.5 */
103 static int get_hub_descriptor(struct usb_device *hdev, void *data, int size)
104 {
105         int i, ret;
106
107         for (i = 0; i < 3; i++) {
108                 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
109                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
110                         USB_DT_HUB << 8, 0, data, size,
111                         USB_CTRL_GET_TIMEOUT);
112                 if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
113                         return ret;
114         }
115         return -EINVAL;
116 }
117
118 /*
119  * USB 2.0 spec Section 11.24.2.1
120  */
121 static int clear_hub_feature(struct usb_device *hdev, int feature)
122 {
123         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
124                 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
125 }
126
127 /*
128  * USB 2.0 spec Section 11.24.2.2
129  */
130 static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
131 {
132         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
133                 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
134                 NULL, 0, 1000);
135 }
136
137 /*
138  * USB 2.0 spec Section 11.24.2.13
139  */
140 static int set_port_feature(struct usb_device *hdev, int port1, int feature)
141 {
142         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
143                 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
144                 NULL, 0, 1000);
145 }
146
147 /*
148  * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
149  * for info about using port indicators
150  */
151 static void set_port_led(
152         struct usb_hub *hub,
153         int port1,
154         int selector
155 )
156 {
157         int status = set_port_feature(hub->hdev, (selector << 8) | port1,
158                         USB_PORT_FEAT_INDICATOR);
159         if (status < 0)
160                 dev_dbg (hub->intfdev,
161                         "port %d indicator %s status %d\n",
162                         port1,
163                         ({ char *s; switch (selector) {
164                         case HUB_LED_AMBER: s = "amber"; break;
165                         case HUB_LED_GREEN: s = "green"; break;
166                         case HUB_LED_OFF: s = "off"; break;
167                         case HUB_LED_AUTO: s = "auto"; break;
168                         default: s = "??"; break;
169                         }; s; }),
170                         status);
171 }
172
173 #define LED_CYCLE_PERIOD        ((2*HZ)/3)
174
175 static void led_work (void *__hub)
176 {
177         struct usb_hub          *hub = __hub;
178         struct usb_device       *hdev = hub->hdev;
179         unsigned                i;
180         unsigned                changed = 0;
181         int                     cursor = -1;
182
183         if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
184                 return;
185
186         for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
187                 unsigned        selector, mode;
188
189                 /* 30%-50% duty cycle */
190
191                 switch (hub->indicator[i]) {
192                 /* cycle marker */
193                 case INDICATOR_CYCLE:
194                         cursor = i;
195                         selector = HUB_LED_AUTO;
196                         mode = INDICATOR_AUTO;
197                         break;
198                 /* blinking green = sw attention */
199                 case INDICATOR_GREEN_BLINK:
200                         selector = HUB_LED_GREEN;
201                         mode = INDICATOR_GREEN_BLINK_OFF;
202                         break;
203                 case INDICATOR_GREEN_BLINK_OFF:
204                         selector = HUB_LED_OFF;
205                         mode = INDICATOR_GREEN_BLINK;
206                         break;
207                 /* blinking amber = hw attention */
208                 case INDICATOR_AMBER_BLINK:
209                         selector = HUB_LED_AMBER;
210                         mode = INDICATOR_AMBER_BLINK_OFF;
211                         break;
212                 case INDICATOR_AMBER_BLINK_OFF:
213                         selector = HUB_LED_OFF;
214                         mode = INDICATOR_AMBER_BLINK;
215                         break;
216                 /* blink green/amber = reserved */
217                 case INDICATOR_ALT_BLINK:
218                         selector = HUB_LED_GREEN;
219                         mode = INDICATOR_ALT_BLINK_OFF;
220                         break;
221                 case INDICATOR_ALT_BLINK_OFF:
222                         selector = HUB_LED_AMBER;
223                         mode = INDICATOR_ALT_BLINK;
224                         break;
225                 default:
226                         continue;
227                 }
228                 if (selector != HUB_LED_AUTO)
229                         changed = 1;
230                 set_port_led(hub, i + 1, selector);
231                 hub->indicator[i] = mode;
232         }
233         if (!changed && blinkenlights) {
234                 cursor++;
235                 cursor %= hub->descriptor->bNbrPorts;
236                 set_port_led(hub, cursor + 1, HUB_LED_GREEN);
237                 hub->indicator[cursor] = INDICATOR_CYCLE;
238                 changed++;
239         }
240         if (changed)
241                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
242 }
243
244 /* use a short timeout for hub/port status fetches */
245 #define USB_STS_TIMEOUT         1000
246 #define USB_STS_RETRIES         5
247
248 /*
249  * USB 2.0 spec Section 11.24.2.6
250  */
251 static int get_hub_status(struct usb_device *hdev,
252                 struct usb_hub_status *data)
253 {
254         int i, status = -ETIMEDOUT;
255
256         for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
257                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
258                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
259                         data, sizeof(*data), USB_STS_TIMEOUT);
260         }
261         return status;
262 }
263
264 /*
265  * USB 2.0 spec Section 11.24.2.7
266  */
267 static int get_port_status(struct usb_device *hdev, int port1,
268                 struct usb_port_status *data)
269 {
270         int i, status = -ETIMEDOUT;
271
272         for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
273                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
274                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
275                         data, sizeof(*data), USB_STS_TIMEOUT);
276         }
277         return status;
278 }
279
280 static void kick_khubd(struct usb_hub *hub)
281 {
282         unsigned long   flags;
283
284         spin_lock_irqsave(&hub_event_lock, flags);
285         if (list_empty(&hub->event_list)) {
286                 list_add_tail(&hub->event_list, &hub_event_list);
287                 wake_up(&khubd_wait);
288         }
289         spin_unlock_irqrestore(&hub_event_lock, flags);
290 }
291
292 void usb_kick_khubd(struct usb_device *hdev)
293 {
294         kick_khubd(hdev_to_hub(hdev));
295 }
296
297
298 /* completion function, fires on port status changes and various faults */
299 static void hub_irq(struct urb *urb, struct pt_regs *regs)
300 {
301         struct usb_hub *hub = (struct usb_hub *)urb->context;
302         int status;
303         int i;
304         unsigned long bits;
305
306         switch (urb->status) {
307         case -ENOENT:           /* synchronous unlink */
308         case -ECONNRESET:       /* async unlink */
309         case -ESHUTDOWN:        /* hardware going away */
310                 return;
311
312         default:                /* presumably an error */
313                 /* Cause a hub reset after 10 consecutive errors */
314                 dev_dbg (hub->intfdev, "transfer --> %d\n", urb->status);
315                 if ((++hub->nerrors < 10) || hub->error)
316                         goto resubmit;
317                 hub->error = urb->status;
318                 /* FALL THROUGH */
319         
320         /* let khubd handle things */
321         case 0:                 /* we got data:  port status changed */
322                 bits = 0;
323                 for (i = 0; i < urb->actual_length; ++i)
324                         bits |= ((unsigned long) ((*hub->buffer)[i]))
325                                         << (i*8);
326                 hub->event_bits[0] = bits;
327                 break;
328         }
329
330         hub->nerrors = 0;
331
332         /* Something happened, let khubd figure it out */
333         kick_khubd(hub);
334
335 resubmit:
336         if (hub->quiescing)
337                 return;
338
339         if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
340                         && status != -ENODEV && status != -EPERM)
341                 dev_err (hub->intfdev, "resubmit --> %d\n", status);
342 }
343
344 /* USB 2.0 spec Section 11.24.2.3 */
345 static inline int
346 hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
347 {
348         return usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
349                                HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
350                                tt, NULL, 0, 1000);
351 }
352
353 /*
354  * enumeration blocks khubd for a long time. we use keventd instead, since
355  * long blocking there is the exception, not the rule.  accordingly, HCDs
356  * talking to TTs must queue control transfers (not just bulk and iso), so
357  * both can talk to the same hub concurrently.
358  */
359 static void hub_tt_kevent (void *arg)
360 {
361         struct usb_hub          *hub = arg;
362         unsigned long           flags;
363
364         spin_lock_irqsave (&hub->tt.lock, flags);
365         while (!list_empty (&hub->tt.clear_list)) {
366                 struct list_head        *temp;
367                 struct usb_tt_clear     *clear;
368                 struct usb_device       *hdev = hub->hdev;
369                 int                     status;
370
371                 temp = hub->tt.clear_list.next;
372                 clear = list_entry (temp, struct usb_tt_clear, clear_list);
373                 list_del (&clear->clear_list);
374
375                 /* drop lock so HCD can concurrently report other TT errors */
376                 spin_unlock_irqrestore (&hub->tt.lock, flags);
377                 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
378                 spin_lock_irqsave (&hub->tt.lock, flags);
379
380                 if (status)
381                         dev_err (&hdev->dev,
382                                 "clear tt %d (%04x) error %d\n",
383                                 clear->tt, clear->devinfo, status);
384                 kfree(clear);
385         }
386         spin_unlock_irqrestore (&hub->tt.lock, flags);
387 }
388
389 /**
390  * usb_hub_tt_clear_buffer - clear control/bulk TT state in high speed hub
391  * @udev: the device whose split transaction failed
392  * @pipe: identifies the endpoint of the failed transaction
393  *
394  * High speed HCDs use this to tell the hub driver that some split control or
395  * bulk transaction failed in a way that requires clearing internal state of
396  * a transaction translator.  This is normally detected (and reported) from
397  * interrupt context.
398  *
399  * It may not be possible for that hub to handle additional full (or low)
400  * speed transactions until that state is fully cleared out.
401  */
402 void usb_hub_tt_clear_buffer (struct usb_device *udev, int pipe)
403 {
404         struct usb_tt           *tt = udev->tt;
405         unsigned long           flags;
406         struct usb_tt_clear     *clear;
407
408         /* we've got to cope with an arbitrary number of pending TT clears,
409          * since each TT has "at least two" buffers that can need it (and
410          * there can be many TTs per hub).  even if they're uncommon.
411          */
412         if ((clear = kmalloc (sizeof *clear, SLAB_ATOMIC)) == NULL) {
413                 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
414                 /* FIXME recover somehow ... RESET_TT? */
415                 return;
416         }
417
418         /* info that CLEAR_TT_BUFFER needs */
419         clear->tt = tt->multi ? udev->ttport : 1;
420         clear->devinfo = usb_pipeendpoint (pipe);
421         clear->devinfo |= udev->devnum << 4;
422         clear->devinfo |= usb_pipecontrol (pipe)
423                         ? (USB_ENDPOINT_XFER_CONTROL << 11)
424                         : (USB_ENDPOINT_XFER_BULK << 11);
425         if (usb_pipein (pipe))
426                 clear->devinfo |= 1 << 15;
427         
428         /* tell keventd to clear state for this TT */
429         spin_lock_irqsave (&tt->lock, flags);
430         list_add_tail (&clear->clear_list, &tt->clear_list);
431         schedule_work (&tt->kevent);
432         spin_unlock_irqrestore (&tt->lock, flags);
433 }
434
435 static void hub_power_on(struct usb_hub *hub)
436 {
437         int port1;
438         unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
439         u16 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
440
441         /* if hub supports power switching, enable power on each port */
442         if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2) {
443                 dev_dbg(hub->intfdev, "enabling power on all ports\n");
444                 for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
445                         set_port_feature(hub->hdev, port1,
446                                         USB_PORT_FEAT_POWER);
447         }
448
449         /* Wait at least 100 msec for power to become stable */
450         msleep(max(pgood_delay, (unsigned) 100));
451 }
452
453 static inline void __hub_quiesce(struct usb_hub *hub)
454 {
455         /* (nonblocking) khubd and related activity won't re-trigger */
456         hub->quiescing = 1;
457         hub->activating = 0;
458         hub->resume_root_hub = 0;
459 }
460
461 static void hub_quiesce(struct usb_hub *hub)
462 {
463         /* (blocking) stop khubd and related activity */
464         __hub_quiesce(hub);
465         usb_kill_urb(hub->urb);
466         if (hub->has_indicators)
467                 cancel_delayed_work(&hub->leds);
468         if (hub->has_indicators || hub->tt.hub)
469                 flush_scheduled_work();
470 }
471
472 static void hub_activate(struct usb_hub *hub)
473 {
474         int     status;
475
476         hub->quiescing = 0;
477         hub->activating = 1;
478         hub->resume_root_hub = 0;
479         status = usb_submit_urb(hub->urb, GFP_NOIO);
480         if (status < 0)
481                 dev_err(hub->intfdev, "activate --> %d\n", status);
482         if (hub->has_indicators && blinkenlights)
483                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
484
485         /* scan all ports ASAP */
486         kick_khubd(hub);
487 }
488
489 static int hub_hub_status(struct usb_hub *hub,
490                 u16 *status, u16 *change)
491 {
492         int ret;
493
494         ret = get_hub_status(hub->hdev, &hub->status->hub);
495         if (ret < 0)
496                 dev_err (hub->intfdev,
497                         "%s failed (err = %d)\n", __FUNCTION__, ret);
498         else {
499                 *status = le16_to_cpu(hub->status->hub.wHubStatus);
500                 *change = le16_to_cpu(hub->status->hub.wHubChange); 
501                 ret = 0;
502         }
503         return ret;
504 }
505
506 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
507 {
508         struct usb_device *hdev = hub->hdev;
509         int ret;
510
511         if (hdev->children[port1-1] && set_state) {
512                 usb_set_device_state(hdev->children[port1-1],
513                                 USB_STATE_NOTATTACHED);
514         }
515         ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
516         if (ret)
517                 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
518                         port1, ret);
519
520         return ret;
521 }
522
523 static int hub_configure(struct usb_hub *hub,
524         struct usb_endpoint_descriptor *endpoint)
525 {
526         struct usb_device *hdev = hub->hdev;
527         struct device *hub_dev = hub->intfdev;
528         u16 hubstatus, hubchange;
529         u16 wHubCharacteristics;
530         unsigned int pipe;
531         int maxp, ret;
532         char *message;
533
534         hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
535                         &hub->buffer_dma);
536         if (!hub->buffer) {
537                 message = "can't allocate hub irq buffer";
538                 ret = -ENOMEM;
539                 goto fail;
540         }
541
542         hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
543         if (!hub->status) {
544                 message = "can't kmalloc hub status buffer";
545                 ret = -ENOMEM;
546                 goto fail;
547         }
548
549         hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
550         if (!hub->descriptor) {
551                 message = "can't kmalloc hub descriptor";
552                 ret = -ENOMEM;
553                 goto fail;
554         }
555
556         /* Request the entire hub descriptor.
557          * hub->descriptor can handle USB_MAXCHILDREN ports,
558          * but the hub can/will return fewer bytes here.
559          */
560         ret = get_hub_descriptor(hdev, hub->descriptor,
561                         sizeof(*hub->descriptor));
562         if (ret < 0) {
563                 message = "can't read hub descriptor";
564                 goto fail;
565         } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
566                 message = "hub has too many ports!";
567                 ret = -ENODEV;
568                 goto fail;
569         }
570
571         hdev->maxchild = hub->descriptor->bNbrPorts;
572         dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
573                 (hdev->maxchild == 1) ? "" : "s");
574
575         wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
576
577         if (wHubCharacteristics & HUB_CHAR_COMPOUND) {
578                 int     i;
579                 char    portstr [USB_MAXCHILDREN + 1];
580
581                 for (i = 0; i < hdev->maxchild; i++)
582                         portstr[i] = hub->descriptor->DeviceRemovable
583                                     [((i + 1) / 8)] & (1 << ((i + 1) % 8))
584                                 ? 'F' : 'R';
585                 portstr[hdev->maxchild] = 0;
586                 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
587         } else
588                 dev_dbg(hub_dev, "standalone hub\n");
589
590         switch (wHubCharacteristics & HUB_CHAR_LPSM) {
591                 case 0x00:
592                         dev_dbg(hub_dev, "ganged power switching\n");
593                         break;
594                 case 0x01:
595                         dev_dbg(hub_dev, "individual port power switching\n");
596                         break;
597                 case 0x02:
598                 case 0x03:
599                         dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
600                         break;
601         }
602
603         switch (wHubCharacteristics & HUB_CHAR_OCPM) {
604                 case 0x00:
605                         dev_dbg(hub_dev, "global over-current protection\n");
606                         break;
607                 case 0x08:
608                         dev_dbg(hub_dev, "individual port over-current protection\n");
609                         break;
610                 case 0x10:
611                 case 0x18:
612                         dev_dbg(hub_dev, "no over-current protection\n");
613                         break;
614         }
615
616         spin_lock_init (&hub->tt.lock);
617         INIT_LIST_HEAD (&hub->tt.clear_list);
618         INIT_WORK (&hub->tt.kevent, hub_tt_kevent, hub);
619         switch (hdev->descriptor.bDeviceProtocol) {
620                 case 0:
621                         break;
622                 case 1:
623                         dev_dbg(hub_dev, "Single TT\n");
624                         hub->tt.hub = hdev;
625                         break;
626                 case 2:
627                         ret = usb_set_interface(hdev, 0, 1);
628                         if (ret == 0) {
629                                 dev_dbg(hub_dev, "TT per port\n");
630                                 hub->tt.multi = 1;
631                         } else
632                                 dev_err(hub_dev, "Using single TT (err %d)\n",
633                                         ret);
634                         hub->tt.hub = hdev;
635                         break;
636                 default:
637                         dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
638                                 hdev->descriptor.bDeviceProtocol);
639                         break;
640         }
641
642         /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
643         switch (wHubCharacteristics & HUB_CHAR_TTTT) {
644                 case HUB_TTTT_8_BITS:
645                         if (hdev->descriptor.bDeviceProtocol != 0) {
646                                 hub->tt.think_time = 666;
647                                 dev_dbg(hub_dev, "TT requires at most %d "
648                                                 "FS bit times (%d ns)\n",
649                                         8, hub->tt.think_time);
650                         }
651                         break;
652                 case HUB_TTTT_16_BITS:
653                         hub->tt.think_time = 666 * 2;
654                         dev_dbg(hub_dev, "TT requires at most %d "
655                                         "FS bit times (%d ns)\n",
656                                 16, hub->tt.think_time);
657                         break;
658                 case HUB_TTTT_24_BITS:
659                         hub->tt.think_time = 666 * 3;
660                         dev_dbg(hub_dev, "TT requires at most %d "
661                                         "FS bit times (%d ns)\n",
662                                 24, hub->tt.think_time);
663                         break;
664                 case HUB_TTTT_32_BITS:
665                         hub->tt.think_time = 666 * 4;
666                         dev_dbg(hub_dev, "TT requires at most %d "
667                                         "FS bit times (%d ns)\n",
668                                 32, hub->tt.think_time);
669                         break;
670         }
671
672         /* probe() zeroes hub->indicator[] */
673         if (wHubCharacteristics & HUB_CHAR_PORTIND) {
674                 hub->has_indicators = 1;
675                 dev_dbg(hub_dev, "Port indicators are supported\n");
676         }
677
678         dev_dbg(hub_dev, "power on to power good time: %dms\n",
679                 hub->descriptor->bPwrOn2PwrGood * 2);
680
681         /* power budgeting mostly matters with bus-powered hubs,
682          * and battery-powered root hubs (may provide just 8 mA).
683          */
684         ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
685         if (ret < 0) {
686                 message = "can't get hub status";
687                 goto fail;
688         }
689         le16_to_cpus(&hubstatus);
690         if (hdev == hdev->bus->root_hub) {
691                 struct usb_hcd *hcd =
692                                 container_of(hdev->bus, struct usb_hcd, self);
693
694                 hub->power_budget = min(500u, hcd->power_budget) / 2;
695         } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
696                 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
697                         hub->descriptor->bHubContrCurrent);
698                 hub->power_budget = (501 - hub->descriptor->bHubContrCurrent)
699                                         / 2;
700         }
701         if (hub->power_budget)
702                 dev_dbg(hub_dev, "%dmA bus power budget for children\n",
703                         hub->power_budget * 2);
704
705
706         ret = hub_hub_status(hub, &hubstatus, &hubchange);
707         if (ret < 0) {
708                 message = "can't get hub status";
709                 goto fail;
710         }
711
712         /* local power status reports aren't always correct */
713         if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
714                 dev_dbg(hub_dev, "local power source is %s\n",
715                         (hubstatus & HUB_STATUS_LOCAL_POWER)
716                         ? "lost (inactive)" : "good");
717
718         if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
719                 dev_dbg(hub_dev, "%sover-current condition exists\n",
720                         (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
721
722         /* set up the interrupt endpoint */
723         pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
724         maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
725
726         if (maxp > sizeof(*hub->buffer))
727                 maxp = sizeof(*hub->buffer);
728
729         hub->urb = usb_alloc_urb(0, GFP_KERNEL);
730         if (!hub->urb) {
731                 message = "couldn't allocate interrupt urb";
732                 ret = -ENOMEM;
733                 goto fail;
734         }
735
736         usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
737                 hub, endpoint->bInterval);
738         hub->urb->transfer_dma = hub->buffer_dma;
739         hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
740
741         /* maybe cycle the hub leds */
742         if (hub->has_indicators && blinkenlights)
743                 hub->indicator [0] = INDICATOR_CYCLE;
744
745         hub_power_on(hub);
746         hub_activate(hub);
747         return 0;
748
749 fail:
750         dev_err (hub_dev, "config failed, %s (err %d)\n",
751                         message, ret);
752         /* hub_disconnect() frees urb and descriptor */
753         return ret;
754 }
755
756 static unsigned highspeed_hubs;
757
758 /* Called after the hub driver is unbound from a hub with children */
759 static void hub_remove_children_work(void *__hub)
760 {
761         struct usb_hub          *hub = __hub;
762         struct usb_device       *hdev = hub->hdev;
763         int                     i;
764
765         kfree(hub);
766
767         usb_lock_device(hdev);
768         for (i = 0; i < hdev->maxchild; ++i) {
769                 if (hdev->children[i])
770                         usb_disconnect(&hdev->children[i]);
771         }
772         usb_unlock_device(hdev);
773         usb_put_dev(hdev);
774 }
775
776 static void hub_disconnect(struct usb_interface *intf)
777 {
778         struct usb_hub *hub = usb_get_intfdata (intf);
779         struct usb_device *hdev;
780         int n, port1;
781
782         usb_set_intfdata (intf, NULL);
783         hdev = hub->hdev;
784
785         if (hdev->speed == USB_SPEED_HIGH)
786                 highspeed_hubs--;
787
788         hub_quiesce(hub);
789         usb_free_urb(hub->urb);
790         hub->urb = NULL;
791
792         spin_lock_irq(&hub_event_lock);
793         list_del_init(&hub->event_list);
794         spin_unlock_irq(&hub_event_lock);
795
796         kfree(hub->descriptor);
797         hub->descriptor = NULL;
798
799         kfree(hub->status);
800         hub->status = NULL;
801
802         if (hub->buffer) {
803                 usb_buffer_free(hdev, sizeof(*hub->buffer), hub->buffer,
804                                 hub->buffer_dma);
805                 hub->buffer = NULL;
806         }
807
808         /* If there are any children then this is an unbind only, not a
809          * physical disconnection.  The active ports must be disabled
810          * and later on we must call usb_disconnect().  We can't call
811          * it now because we may not hold the hub's device lock.
812          */
813         n = 0;
814         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
815                 if (hdev->children[port1 - 1]) {
816                         ++n;
817                         hub_port_disable(hub, port1, 1);
818                 }
819         }
820
821         if (n == 0)
822                 kfree(hub);
823         else {
824                 /* Reuse the hub->leds work_struct for our own purposes */
825                 INIT_WORK(&hub->leds, hub_remove_children_work, hub);
826                 schedule_work(&hub->leds);
827                 usb_get_dev(hdev);
828         }
829 }
830
831 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
832 {
833         struct usb_host_interface *desc;
834         struct usb_endpoint_descriptor *endpoint;
835         struct usb_device *hdev;
836         struct usb_hub *hub;
837
838         desc = intf->cur_altsetting;
839         hdev = interface_to_usbdev(intf);
840
841         /* Some hubs have a subclass of 1, which AFAICT according to the */
842         /*  specs is not defined, but it works */
843         if ((desc->desc.bInterfaceSubClass != 0) &&
844             (desc->desc.bInterfaceSubClass != 1)) {
845 descriptor_error:
846                 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
847                 return -EIO;
848         }
849
850         /* Multiple endpoints? What kind of mutant ninja-hub is this? */
851         if (desc->desc.bNumEndpoints != 1)
852                 goto descriptor_error;
853
854         endpoint = &desc->endpoint[0].desc;
855
856         /* Output endpoint? Curiouser and curiouser.. */
857         if (!(endpoint->bEndpointAddress & USB_DIR_IN))
858                 goto descriptor_error;
859
860         /* If it's not an interrupt endpoint, we'd better punt! */
861         if ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
862                         != USB_ENDPOINT_XFER_INT)
863                 goto descriptor_error;
864
865         /* We found a hub */
866         dev_info (&intf->dev, "USB hub found\n");
867
868         hub = kmalloc(sizeof(*hub), GFP_KERNEL);
869         if (!hub) {
870                 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
871                 return -ENOMEM;
872         }
873
874         memset(hub, 0, sizeof(*hub));
875
876         INIT_LIST_HEAD(&hub->event_list);
877         hub->intfdev = &intf->dev;
878         hub->hdev = hdev;
879         INIT_WORK(&hub->leds, led_work, hub);
880
881         usb_set_intfdata (intf, hub);
882
883         if (hdev->speed == USB_SPEED_HIGH)
884                 highspeed_hubs++;
885
886         if (hub_configure(hub, endpoint) >= 0)
887                 return 0;
888
889         hub_disconnect (intf);
890         return -ENODEV;
891 }
892
893 static int
894 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
895 {
896         struct usb_device *hdev = interface_to_usbdev (intf);
897
898         /* assert ifno == 0 (part of hub spec) */
899         switch (code) {
900         case USBDEVFS_HUB_PORTINFO: {
901                 struct usbdevfs_hub_portinfo *info = user_data;
902                 int i;
903
904                 spin_lock_irq(&device_state_lock);
905                 if (hdev->devnum <= 0)
906                         info->nports = 0;
907                 else {
908                         info->nports = hdev->maxchild;
909                         for (i = 0; i < info->nports; i++) {
910                                 if (hdev->children[i] == NULL)
911                                         info->port[i] = 0;
912                                 else
913                                         info->port[i] =
914                                                 hdev->children[i]->devnum;
915                         }
916                 }
917                 spin_unlock_irq(&device_state_lock);
918
919                 return info->nports + 1;
920                 }
921
922         default:
923                 return -ENOSYS;
924         }
925 }
926
927 /* caller has locked the hub device */
928 static void hub_pre_reset(struct usb_hub *hub)
929 {
930         struct usb_device *hdev = hub->hdev;
931         int i;
932
933         for (i = 0; i < hdev->maxchild; ++i) {
934                 if (hdev->children[i])
935                         usb_disconnect(&hdev->children[i]);
936         }
937         hub_quiesce(hub);
938 }
939
940 /* caller has locked the hub device */
941 static void hub_post_reset(struct usb_hub *hub)
942 {
943         hub_activate(hub);
944         hub_power_on(hub);
945 }
946
947
948 /* grab device/port lock, returning index of that port (zero based).
949  * protects the upstream link used by this device from concurrent
950  * tree operations like suspend, resume, reset, and disconnect, which
951  * apply to everything downstream of a given port.
952  */
953 static int locktree(struct usb_device *udev)
954 {
955         int                     t;
956         struct usb_device       *hdev;
957
958         if (!udev)
959                 return -ENODEV;
960
961         /* root hub is always the first lock in the series */
962         hdev = udev->parent;
963         if (!hdev) {
964                 usb_lock_device(udev);
965                 return 0;
966         }
967
968         /* on the path from root to us, lock everything from
969          * top down, dropping parent locks when not needed
970          */
971         t = locktree(hdev);
972         if (t < 0)
973                 return t;
974         for (t = 0; t < hdev->maxchild; t++) {
975                 if (hdev->children[t] == udev) {
976                         /* everything is fail-fast once disconnect
977                          * processing starts
978                          */
979                         if (udev->state == USB_STATE_NOTATTACHED)
980                                 break;
981
982                         /* when everyone grabs locks top->bottom,
983                          * non-overlapping work may be concurrent
984                          */
985                         down(&udev->serialize);
986                         up(&hdev->serialize);
987                         return t + 1;
988                 }
989         }
990         usb_unlock_device(hdev);
991         return -ENODEV;
992 }
993
994 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
995 {
996         int i;
997
998         for (i = 0; i < udev->maxchild; ++i) {
999                 if (udev->children[i])
1000                         recursively_mark_NOTATTACHED(udev->children[i]);
1001         }
1002         udev->state = USB_STATE_NOTATTACHED;
1003 }
1004
1005 /**
1006  * usb_set_device_state - change a device's current state (usbcore, hcds)
1007  * @udev: pointer to device whose state should be changed
1008  * @new_state: new state value to be stored
1009  *
1010  * udev->state is _not_ fully protected by the device lock.  Although
1011  * most transitions are made only while holding the lock, the state can
1012  * can change to USB_STATE_NOTATTACHED at almost any time.  This
1013  * is so that devices can be marked as disconnected as soon as possible,
1014  * without having to wait for any semaphores to be released.  As a result,
1015  * all changes to any device's state must be protected by the
1016  * device_state_lock spinlock.
1017  *
1018  * Once a device has been added to the device tree, all changes to its state
1019  * should be made using this routine.  The state should _not_ be set directly.
1020  *
1021  * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1022  * Otherwise udev->state is set to new_state, and if new_state is
1023  * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1024  * to USB_STATE_NOTATTACHED.
1025  */
1026 void usb_set_device_state(struct usb_device *udev,
1027                 enum usb_device_state new_state)
1028 {
1029         unsigned long flags;
1030
1031         spin_lock_irqsave(&device_state_lock, flags);
1032         if (udev->state == USB_STATE_NOTATTACHED)
1033                 ;       /* do nothing */
1034         else if (new_state != USB_STATE_NOTATTACHED) {
1035                 udev->state = new_state;
1036                 if (new_state == USB_STATE_CONFIGURED)
1037                         device_init_wakeup(&udev->dev,
1038                                 (udev->actconfig->desc.bmAttributes
1039                                  & USB_CONFIG_ATT_WAKEUP));
1040                 else if (new_state != USB_STATE_SUSPENDED)
1041                         device_init_wakeup(&udev->dev, 0);
1042         } else
1043                 recursively_mark_NOTATTACHED(udev);
1044         spin_unlock_irqrestore(&device_state_lock, flags);
1045 }
1046 EXPORT_SYMBOL(usb_set_device_state);
1047
1048
1049 static void choose_address(struct usb_device *udev)
1050 {
1051         int             devnum;
1052         struct usb_bus  *bus = udev->bus;
1053
1054         /* If khubd ever becomes multithreaded, this will need a lock */
1055
1056         /* Try to allocate the next devnum beginning at bus->devnum_next. */
1057         devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1058                         bus->devnum_next);
1059         if (devnum >= 128)
1060                 devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
1061
1062         bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1063
1064         if (devnum < 128) {
1065                 set_bit(devnum, bus->devmap.devicemap);
1066                 udev->devnum = devnum;
1067         }
1068 }
1069
1070 static void release_address(struct usb_device *udev)
1071 {
1072         if (udev->devnum > 0) {
1073                 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1074                 udev->devnum = -1;
1075         }
1076 }
1077
1078 /**
1079  * usb_disconnect - disconnect a device (usbcore-internal)
1080  * @pdev: pointer to device being disconnected
1081  * Context: !in_interrupt ()
1082  *
1083  * Something got disconnected. Get rid of it and all of its children.
1084  *
1085  * If *pdev is a normal device then the parent hub must already be locked.
1086  * If *pdev is a root hub then this routine will acquire the
1087  * usb_bus_list_lock on behalf of the caller.
1088  *
1089  * Only hub drivers (including virtual root hub drivers for host
1090  * controllers) should ever call this.
1091  *
1092  * This call is synchronous, and may not be used in an interrupt context.
1093  */
1094 void usb_disconnect(struct usb_device **pdev)
1095 {
1096         struct usb_device       *udev = *pdev;
1097         int                     i;
1098
1099         if (!udev) {
1100                 pr_debug ("%s nodev\n", __FUNCTION__);
1101                 return;
1102         }
1103
1104         /* mark the device as inactive, so any further urb submissions for
1105          * this device (and any of its children) will fail immediately.
1106          * this quiesces everyting except pending urbs.
1107          */
1108         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1109
1110         /* lock the bus list on behalf of HCDs unregistering their root hubs */
1111         if (!udev->parent) {
1112                 down(&usb_bus_list_lock);
1113                 usb_lock_device(udev);
1114         } else
1115                 down(&udev->serialize);
1116
1117         dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1118
1119         /* Free up all the children before we remove this device */
1120         for (i = 0; i < USB_MAXCHILDREN; i++) {
1121                 if (udev->children[i])
1122                         usb_disconnect(&udev->children[i]);
1123         }
1124
1125         /* deallocate hcd/hardware state ... nuking all pending urbs and
1126          * cleaning up all state associated with the current configuration
1127          * so that the hardware is now fully quiesced.
1128          */
1129         usb_disable_device(udev, 0);
1130
1131         usb_notify_remove_device(udev);
1132
1133         /* Free the device number, remove the /proc/bus/usb entry and
1134          * the sysfs attributes, and delete the parent's children[]
1135          * (or root_hub) pointer.
1136          */
1137         dev_dbg (&udev->dev, "unregistering device\n");
1138         release_address(udev);
1139         usbfs_remove_device(udev);
1140         usbdev_remove(udev);
1141         usb_remove_sysfs_dev_files(udev);
1142
1143         /* Avoid races with recursively_mark_NOTATTACHED() */
1144         spin_lock_irq(&device_state_lock);
1145         *pdev = NULL;
1146         spin_unlock_irq(&device_state_lock);
1147
1148         if (!udev->parent) {
1149                 usb_unlock_device(udev);
1150                 up(&usb_bus_list_lock);
1151         } else
1152                 up(&udev->serialize);
1153
1154         device_unregister(&udev->dev);
1155 }
1156
1157 static int choose_configuration(struct usb_device *udev)
1158 {
1159         int c, i;
1160
1161         /* NOTE: this should interact with hub power budgeting */
1162
1163         c = udev->config[0].desc.bConfigurationValue;
1164         if (udev->descriptor.bNumConfigurations != 1) {
1165                 for (i = 0; i < udev->descriptor.bNumConfigurations; i++) {
1166                         struct usb_interface_descriptor *desc;
1167
1168                         /* heuristic:  Linux is more likely to have class
1169                          * drivers, so avoid vendor-specific interfaces.
1170                          */
1171                         desc = &udev->config[i].intf_cache[0]
1172                                         ->altsetting->desc;
1173                         if (desc->bInterfaceClass == USB_CLASS_VENDOR_SPEC)
1174                                 continue;
1175                         /* COMM/2/all is CDC ACM, except 0xff is MSFT RNDIS.
1176                          * MSFT needs this to be the first config; never use
1177                          * it as the default unless Linux has host-side RNDIS.
1178                          * A second config would ideally be CDC-Ethernet, but
1179                          * may instead be the "vendor specific" CDC subset
1180                          * long used by ARM Linux for sa1100 or pxa255.
1181                          */
1182                         if (desc->bInterfaceClass == USB_CLASS_COMM
1183                                         && desc->bInterfaceSubClass == 2
1184                                         && desc->bInterfaceProtocol == 0xff) {
1185                                 c = udev->config[1].desc.bConfigurationValue;
1186                                 continue;
1187                         }
1188                         c = udev->config[i].desc.bConfigurationValue;
1189                         break;
1190                 }
1191                 dev_info(&udev->dev,
1192                         "configuration #%d chosen from %d choices\n",
1193                         c, udev->descriptor.bNumConfigurations);
1194         }
1195         return c;
1196 }
1197
1198 #ifdef DEBUG
1199 static void show_string(struct usb_device *udev, char *id, char *string)
1200 {
1201         if (!string)
1202                 return;
1203         dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1204 }
1205
1206 #else
1207 static inline void show_string(struct usb_device *udev, char *id, char *string)
1208 {}
1209 #endif
1210
1211 static void get_string(struct usb_device *udev, char **string, int index)
1212 {
1213         char *buf;
1214
1215         if (!index)
1216                 return;
1217         buf = kmalloc(256, GFP_KERNEL);
1218         if (!buf)
1219                 return;
1220         if (usb_string(udev, index, buf, 256) > 0)
1221                 *string = buf;
1222         else
1223                 kfree(buf);
1224 }
1225
1226
1227 #ifdef  CONFIG_USB_OTG
1228 #include "otg_whitelist.h"
1229 #endif
1230
1231 /**
1232  * usb_new_device - perform initial device setup (usbcore-internal)
1233  * @udev: newly addressed device (in ADDRESS state)
1234  *
1235  * This is called with devices which have been enumerated, but not yet
1236  * configured.  The device descriptor is available, but not descriptors
1237  * for any device configuration.  The caller must have locked udev and
1238  * either the parent hub (if udev is a normal device) or else the
1239  * usb_bus_list_lock (if udev is a root hub).  The parent's pointer to
1240  * udev has already been installed, but udev is not yet visible through
1241  * sysfs or other filesystem code.
1242  *
1243  * Returns 0 for success (device is configured and listed, with its
1244  * interfaces, in sysfs); else a negative errno value.
1245  *
1246  * This call is synchronous, and may not be used in an interrupt context.
1247  *
1248  * Only the hub driver should ever call this; root hub registration
1249  * uses it indirectly.
1250  */
1251 int usb_new_device(struct usb_device *udev)
1252 {
1253         int err;
1254         int c;
1255
1256         err = usb_get_configuration(udev);
1257         if (err < 0) {
1258                 dev_err(&udev->dev, "can't read configurations, error %d\n",
1259                         err);
1260                 goto fail;
1261         }
1262
1263         /* read the standard strings and cache them if present */
1264         get_string(udev, &udev->product, udev->descriptor.iProduct);
1265         get_string(udev, &udev->manufacturer, udev->descriptor.iManufacturer);
1266         get_string(udev, &udev->serial, udev->descriptor.iSerialNumber);
1267
1268         /* Tell the world! */
1269         dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
1270                         "SerialNumber=%d\n",
1271                         udev->descriptor.iManufacturer,
1272                         udev->descriptor.iProduct,
1273                         udev->descriptor.iSerialNumber);
1274         show_string(udev, "Product", udev->product);
1275         show_string(udev, "Manufacturer", udev->manufacturer);
1276         show_string(udev, "SerialNumber", udev->serial);
1277
1278 #ifdef  CONFIG_USB_OTG
1279         /*
1280          * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1281          * to wake us after we've powered off VBUS; and HNP, switching roles
1282          * "host" to "peripheral".  The OTG descriptor helps figure this out.
1283          */
1284         if (!udev->bus->is_b_host
1285                         && udev->config
1286                         && udev->parent == udev->bus->root_hub) {
1287                 struct usb_otg_descriptor       *desc = 0;
1288                 struct usb_bus                  *bus = udev->bus;
1289
1290                 /* descriptor may appear anywhere in config */
1291                 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1292                                         le16_to_cpu(udev->config[0].desc.wTotalLength),
1293                                         USB_DT_OTG, (void **) &desc) == 0) {
1294                         if (desc->bmAttributes & USB_OTG_HNP) {
1295                                 unsigned                port1;
1296                                 struct usb_device       *root = udev->parent;
1297                                 
1298                                 for (port1 = 1; port1 <= root->maxchild;
1299                                                 port1++) {
1300                                         if (root->children[port1-1] == udev)
1301                                                 break;
1302                                 }
1303
1304                                 dev_info(&udev->dev,
1305                                         "Dual-Role OTG device on %sHNP port\n",
1306                                         (port1 == bus->otg_port)
1307                                                 ? "" : "non-");
1308
1309                                 /* enable HNP before suspend, it's simpler */
1310                                 if (port1 == bus->otg_port)
1311                                         bus->b_hnp_enable = 1;
1312                                 err = usb_control_msg(udev,
1313                                         usb_sndctrlpipe(udev, 0),
1314                                         USB_REQ_SET_FEATURE, 0,
1315                                         bus->b_hnp_enable
1316                                                 ? USB_DEVICE_B_HNP_ENABLE
1317                                                 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1318                                         0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1319                                 if (err < 0) {
1320                                         /* OTG MESSAGE: report errors here,
1321                                          * customize to match your product.
1322                                          */
1323                                         dev_info(&udev->dev,
1324                                                 "can't set HNP mode; %d\n",
1325                                                 err);
1326                                         bus->b_hnp_enable = 0;
1327                                 }
1328                         }
1329                 }
1330         }
1331
1332         if (!is_targeted(udev)) {
1333
1334                 /* Maybe it can talk to us, though we can't talk to it.
1335                  * (Includes HNP test device.)
1336                  */
1337                 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1338                         static int __usb_suspend_device(struct usb_device *,
1339                                                 int port1);
1340                         err = __usb_suspend_device(udev, udev->bus->otg_port);
1341                         if (err < 0)
1342                                 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1343                 }
1344                 err = -ENODEV;
1345                 goto fail;
1346         }
1347 #endif
1348
1349         /* put device-specific files into sysfs */
1350         err = device_add (&udev->dev);
1351         if (err) {
1352                 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1353                 goto fail;
1354         }
1355         usb_create_sysfs_dev_files (udev);
1356
1357         /* choose and set the configuration. that registers the interfaces
1358          * with the driver core, and lets usb device drivers bind to them.
1359          */
1360         c = choose_configuration(udev);
1361         if (c < 0)
1362                 dev_warn(&udev->dev,
1363                                 "can't choose an initial configuration\n");
1364         else {
1365                 err = usb_set_configuration(udev, c);
1366                 if (err) {
1367                         dev_err(&udev->dev, "can't set config #%d, error %d\n",
1368                                         c, err);
1369                         usb_remove_sysfs_dev_files(udev);
1370                         device_del(&udev->dev);
1371                         goto fail;
1372                 }
1373         }
1374
1375         /* USB device state == configured ... usable */
1376         usb_notify_add_device(udev);
1377
1378         /* add a /proc/bus/usb entry */
1379         usbdev_add(udev);
1380         usbfs_add_device(udev);
1381         return 0;
1382
1383 fail:
1384         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1385         return err;
1386 }
1387
1388
1389 static int hub_port_status(struct usb_hub *hub, int port1,
1390                                u16 *status, u16 *change)
1391 {
1392         int ret;
1393
1394         ret = get_port_status(hub->hdev, port1, &hub->status->port);
1395         if (ret < 0)
1396                 dev_err (hub->intfdev,
1397                         "%s failed (err = %d)\n", __FUNCTION__, ret);
1398         else {
1399                 *status = le16_to_cpu(hub->status->port.wPortStatus);
1400                 *change = le16_to_cpu(hub->status->port.wPortChange); 
1401                 ret = 0;
1402         }
1403         return ret;
1404 }
1405
1406 #define PORT_RESET_TRIES        5
1407 #define SET_ADDRESS_TRIES       2
1408 #define GET_DESCRIPTOR_TRIES    2
1409 #define SET_CONFIG_TRIES        (2 * (use_both_schemes + 1))
1410 #define USE_NEW_SCHEME(i)       ((i) / 2 == old_scheme_first)
1411
1412 #define HUB_ROOT_RESET_TIME     50      /* times are in msec */
1413 #define HUB_SHORT_RESET_TIME    10
1414 #define HUB_LONG_RESET_TIME     200
1415 #define HUB_RESET_TIMEOUT       500
1416
1417 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1418                                 struct usb_device *udev, unsigned int delay)
1419 {
1420         int delay_time, ret;
1421         u16 portstatus;
1422         u16 portchange;
1423
1424         for (delay_time = 0;
1425                         delay_time < HUB_RESET_TIMEOUT;
1426                         delay_time += delay) {
1427                 /* wait to give the device a chance to reset */
1428                 msleep(delay);
1429
1430                 /* read and decode port status */
1431                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1432                 if (ret < 0)
1433                         return ret;
1434
1435                 /* Device went away? */
1436                 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1437                         return -ENOTCONN;
1438
1439                 /* bomb out completely if something weird happened */
1440                 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1441                         return -EINVAL;
1442
1443                 /* if we`ve finished resetting, then break out of the loop */
1444                 if (!(portstatus & USB_PORT_STAT_RESET) &&
1445                     (portstatus & USB_PORT_STAT_ENABLE)) {
1446                         if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1447                                 udev->speed = USB_SPEED_HIGH;
1448                         else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1449                                 udev->speed = USB_SPEED_LOW;
1450                         else
1451                                 udev->speed = USB_SPEED_FULL;
1452                         return 0;
1453                 }
1454
1455                 /* switch to the long delay after two short delay failures */
1456                 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
1457                         delay = HUB_LONG_RESET_TIME;
1458
1459                 dev_dbg (hub->intfdev,
1460                         "port %d not reset yet, waiting %dms\n",
1461                         port1, delay);
1462         }
1463
1464         return -EBUSY;
1465 }
1466
1467 static int hub_port_reset(struct usb_hub *hub, int port1,
1468                                 struct usb_device *udev, unsigned int delay)
1469 {
1470         int i, status;
1471
1472         /* Reset the port */
1473         for (i = 0; i < PORT_RESET_TRIES; i++) {
1474                 status = set_port_feature(hub->hdev,
1475                                 port1, USB_PORT_FEAT_RESET);
1476                 if (status)
1477                         dev_err(hub->intfdev,
1478                                         "cannot reset port %d (err = %d)\n",
1479                                         port1, status);
1480                 else {
1481                         status = hub_port_wait_reset(hub, port1, udev, delay);
1482                         if (status && status != -ENOTCONN)
1483                                 dev_dbg(hub->intfdev,
1484                                                 "port_wait_reset: err = %d\n",
1485                                                 status);
1486                 }
1487
1488                 /* return on disconnect or reset */
1489                 switch (status) {
1490                 case 0:
1491                         /* TRSTRCY = 10 ms; plus some extra */
1492                         msleep(10 + 40);
1493                         /* FALL THROUGH */
1494                 case -ENOTCONN:
1495                 case -ENODEV:
1496                         clear_port_feature(hub->hdev,
1497                                 port1, USB_PORT_FEAT_C_RESET);
1498                         /* FIXME need disconnect() for NOTATTACHED device */
1499                         usb_set_device_state(udev, status
1500                                         ? USB_STATE_NOTATTACHED
1501                                         : USB_STATE_DEFAULT);
1502                         return status;
1503                 }
1504
1505                 dev_dbg (hub->intfdev,
1506                         "port %d not enabled, trying reset again...\n",
1507                         port1);
1508                 delay = HUB_LONG_RESET_TIME;
1509         }
1510
1511         dev_err (hub->intfdev,
1512                 "Cannot enable port %i.  Maybe the USB cable is bad?\n",
1513                 port1);
1514
1515         return status;
1516 }
1517
1518 /*
1519  * Disable a port and mark a logical connnect-change event, so that some
1520  * time later khubd will disconnect() any existing usb_device on the port
1521  * and will re-enumerate if there actually is a device attached.
1522  */
1523 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
1524 {
1525         dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
1526         hub_port_disable(hub, port1, 1);
1527
1528         /* FIXME let caller ask to power down the port:
1529          *  - some devices won't enumerate without a VBUS power cycle
1530          *  - SRP saves power that way
1531          *  - ... new call, TBD ...
1532          * That's easy if this hub can switch power per-port, and
1533          * khubd reactivates the port later (timer, SRP, etc).
1534          * Powerdown must be optional, because of reset/DFU.
1535          */
1536
1537         set_bit(port1, hub->change_bits);
1538         kick_khubd(hub);
1539 }
1540
1541
1542 #ifdef  CONFIG_USB_SUSPEND
1543
1544 /*
1545  * Selective port suspend reduces power; most suspended devices draw
1546  * less than 500 uA.  It's also used in OTG, along with remote wakeup.
1547  * All devices below the suspended port are also suspended.
1548  *
1549  * Devices leave suspend state when the host wakes them up.  Some devices
1550  * also support "remote wakeup", where the device can activate the USB
1551  * tree above them to deliver data, such as a keypress or packet.  In
1552  * some cases, this wakes the USB host.
1553  */
1554 static int hub_port_suspend(struct usb_hub *hub, int port1,
1555                 struct usb_device *udev)
1556 {
1557         int     status;
1558
1559         // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
1560
1561         /* enable remote wakeup when appropriate; this lets the device
1562          * wake up the upstream hub (including maybe the root hub).
1563          *
1564          * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
1565          * we don't explicitly enable it here.
1566          */
1567         if (device_may_wakeup(&udev->dev)) {
1568                 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1569                                 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
1570                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1571                                 NULL, 0,
1572                                 USB_CTRL_SET_TIMEOUT);
1573                 if (status)
1574                         dev_dbg(&udev->dev,
1575                                 "won't remote wakeup, status %d\n",
1576                                 status);
1577         }
1578
1579         /* see 7.1.7.6 */
1580         status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
1581         if (status) {
1582                 dev_dbg(hub->intfdev,
1583                         "can't suspend port %d, status %d\n",
1584                         port1, status);
1585                 /* paranoia:  "should not happen" */
1586                 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1587                                 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
1588                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1589                                 NULL, 0,
1590                                 USB_CTRL_SET_TIMEOUT);
1591         } else {
1592                 /* device has up to 10 msec to fully suspend */
1593                 dev_dbg(&udev->dev, "usb suspend\n");
1594                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1595                 msleep(10);
1596         }
1597         return status;
1598 }
1599
1600 /*
1601  * Devices on USB hub ports have only one "suspend" state, corresponding
1602  * to ACPI D2, "may cause the device to lose some context".
1603  * State transitions include:
1604  *
1605  *   - suspend, resume ... when the VBUS power link stays live
1606  *   - suspend, disconnect ... VBUS lost
1607  *
1608  * Once VBUS drop breaks the circuit, the port it's using has to go through
1609  * normal re-enumeration procedures, starting with enabling VBUS power.
1610  * Other than re-initializing the hub (plug/unplug, except for root hubs),
1611  * Linux (2.6) currently has NO mechanisms to initiate that:  no khubd
1612  * timer, no SRP, no requests through sysfs.
1613  *
1614  * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
1615  * the root hub for their bus goes into global suspend ... so we don't
1616  * (falsely) update the device power state to say it suspended.
1617  */
1618 static int __usb_suspend_device (struct usb_device *udev, int port1)
1619 {
1620         int     status = 0;
1621
1622         /* caller owns the udev device lock */
1623         if (port1 < 0)
1624                 return port1;
1625
1626         if (udev->state == USB_STATE_SUSPENDED
1627                         || udev->state == USB_STATE_NOTATTACHED) {
1628                 return 0;
1629         }
1630
1631         /* all interfaces must already be suspended */
1632         if (udev->actconfig) {
1633                 int     i;
1634
1635                 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1636                         struct usb_interface    *intf;
1637
1638                         intf = udev->actconfig->interface[i];
1639                         if (is_active(intf)) {
1640                                 dev_dbg(&intf->dev, "nyet suspended\n");
1641                                 return -EBUSY;
1642                         }
1643                 }
1644         }
1645
1646         /* we only change a device's upstream USB link.
1647          * root hubs have no upstream USB link.
1648          */
1649         if (udev->parent)
1650                 status = hub_port_suspend(hdev_to_hub(udev->parent), port1,
1651                                 udev);
1652
1653         if (status == 0)
1654                 udev->dev.power.power_state = PMSG_SUSPEND;
1655         return status;
1656 }
1657
1658 #endif
1659
1660 /*
1661  * usb_suspend_device - suspend a usb device
1662  * @udev: device that's no longer in active use
1663  * Context: must be able to sleep; device not locked; pm locks held
1664  *
1665  * Suspends a USB device that isn't in active use, conserving power.
1666  * Devices may wake out of a suspend, if anything important happens,
1667  * using the remote wakeup mechanism.  They may also be taken out of
1668  * suspend by the host, using usb_resume_device().  It's also routine
1669  * to disconnect devices while they are suspended.
1670  *
1671  * This only affects the USB hardware for a device; its interfaces
1672  * (and, for hubs, child devices) must already have been suspended.
1673  *
1674  * Suspending OTG devices may trigger HNP, if that's been enabled
1675  * between a pair of dual-role devices.  That will change roles, such
1676  * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
1677  *
1678  * Returns 0 on success, else negative errno.
1679  */
1680 int usb_suspend_device(struct usb_device *udev)
1681 {
1682 #ifdef  CONFIG_USB_SUSPEND
1683         int     port1, status;
1684
1685         port1 = locktree(udev);
1686         if (port1 < 0)
1687                 return port1;
1688
1689         status = __usb_suspend_device(udev, port1);
1690         usb_unlock_device(udev);
1691         return status;
1692 #else
1693         /* NOTE:  udev->state unchanged, it's not lying ... */
1694         udev->dev.power.power_state = PMSG_SUSPEND;
1695         return 0;
1696 #endif
1697 }
1698
1699
1700 /*
1701  * If the USB "suspend" state is in use (rather than "global suspend"),
1702  * many devices will be individually taken out of suspend state using
1703  * special" resume" signaling.  These routines kick in shortly after
1704  * hardware resume signaling is finished, either because of selective
1705  * resume (by host) or remote wakeup (by device) ... now see what changed
1706  * in the tree that's rooted at this device.
1707  */
1708 static int finish_device_resume(struct usb_device *udev)
1709 {
1710         int     status;
1711         u16     devstatus;
1712
1713         /* caller owns the udev device lock */
1714         dev_dbg(&udev->dev, "finish resume\n");
1715
1716         /* usb ch9 identifies four variants of SUSPENDED, based on what
1717          * state the device resumes to.  Linux currently won't see the
1718          * first two on the host side; they'd be inside hub_port_init()
1719          * during many timeouts, but khubd can't suspend until later.
1720          */
1721         usb_set_device_state(udev, udev->actconfig
1722                         ? USB_STATE_CONFIGURED
1723                         : USB_STATE_ADDRESS);
1724
1725         /* 10.5.4.5 says be sure devices in the tree are still there.
1726          * For now let's assume the device didn't go crazy on resume,
1727          * and device drivers will know about any resume quirks.
1728          */
1729         status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
1730         if (status < 0)
1731                 dev_dbg(&udev->dev,
1732                         "gone after usb resume? status %d\n",
1733                         status);
1734         else if (udev->actconfig) {
1735                 unsigned        i;
1736                 int             (*resume)(struct device *);
1737
1738                 le16_to_cpus(&devstatus);
1739                 if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)
1740                                 && udev->parent) {
1741                         status = usb_control_msg(udev,
1742                                         usb_sndctrlpipe(udev, 0),
1743                                         USB_REQ_CLEAR_FEATURE,
1744                                                 USB_RECIP_DEVICE,
1745                                         USB_DEVICE_REMOTE_WAKEUP, 0,
1746                                         NULL, 0,
1747                                         USB_CTRL_SET_TIMEOUT);
1748                         if (status) {
1749                                 dev_dbg(&udev->dev, "disable remote "
1750                                         "wakeup, status %d\n", status);
1751                                 status = 0;
1752                         }
1753                 }
1754
1755                 /* resume interface drivers; if this is a hub, it
1756                  * may have a child resume event to deal with soon
1757                  */
1758                 resume = udev->dev.bus->resume;
1759                 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++)
1760                         (void) resume(&udev->actconfig->interface[i]->dev);
1761                 status = 0;
1762
1763         } else if (udev->devnum <= 0) {
1764                 dev_dbg(&udev->dev, "bogus resume!\n");
1765                 status = -EINVAL;
1766         }
1767         return status;
1768 }
1769
1770 #ifdef  CONFIG_USB_SUSPEND
1771
1772 static int
1773 hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
1774 {
1775         int     status;
1776
1777         // dev_dbg(hub->intfdev, "resume port %d\n", port1);
1778
1779         /* see 7.1.7.7; affects power usage, but not budgeting */
1780         status = clear_port_feature(hub->hdev,
1781                         port1, USB_PORT_FEAT_SUSPEND);
1782         if (status) {
1783                 dev_dbg(hub->intfdev,
1784                         "can't resume port %d, status %d\n",
1785                         port1, status);
1786         } else {
1787                 u16             devstatus;
1788                 u16             portchange;
1789
1790                 /* drive resume for at least 20 msec */
1791                 if (udev)
1792                         dev_dbg(&udev->dev, "RESUME\n");
1793                 msleep(25);
1794
1795 #define LIVE_FLAGS      ( USB_PORT_STAT_POWER \
1796                         | USB_PORT_STAT_ENABLE \
1797                         | USB_PORT_STAT_CONNECTION)
1798
1799                 /* Virtual root hubs can trigger on GET_PORT_STATUS to
1800                  * stop resume signaling.  Then finish the resume
1801                  * sequence.
1802                  */
1803                 devstatus = portchange = 0;
1804                 status = hub_port_status(hub, port1,
1805                                 &devstatus, &portchange);
1806                 if (status < 0
1807                                 || (devstatus & LIVE_FLAGS) != LIVE_FLAGS
1808                                 || (devstatus & USB_PORT_STAT_SUSPEND) != 0
1809                                 ) {
1810                         dev_dbg(hub->intfdev,
1811                                 "port %d status %04x.%04x after resume, %d\n",
1812                                 port1, portchange, devstatus, status);
1813                 } else {
1814                         /* TRSMRCY = 10 msec */
1815                         msleep(10);
1816                         if (udev)
1817                                 status = finish_device_resume(udev);
1818                 }
1819         }
1820         if (status < 0)
1821                 hub_port_logical_disconnect(hub, port1);
1822
1823         return status;
1824 }
1825
1826 #endif
1827
1828 /*
1829  * usb_resume_device - re-activate a suspended usb device
1830  * @udev: device to re-activate
1831  * Context: must be able to sleep; device not locked; pm locks held
1832  *
1833  * This will re-activate the suspended device, increasing power usage
1834  * while letting drivers communicate again with its endpoints.
1835  * USB resume explicitly guarantees that the power session between
1836  * the host and the device is the same as it was when the device
1837  * suspended.
1838  *
1839  * Returns 0 on success, else negative errno.
1840  */
1841 int usb_resume_device(struct usb_device *udev)
1842 {
1843         int     port1, status;
1844
1845         port1 = locktree(udev);
1846         if (port1 < 0)
1847                 return port1;
1848
1849 #ifdef  CONFIG_USB_SUSPEND
1850         /* selective resume of one downstream hub-to-device port */
1851         if (udev->parent) {
1852                 if (udev->state == USB_STATE_SUSPENDED) {
1853                         // NOTE swsusp may bork us, device state being wrong...
1854                         // NOTE this fails if parent is also suspended...
1855                         status = hub_port_resume(hdev_to_hub(udev->parent),
1856                                         port1, udev);
1857                 } else
1858                         status = 0;
1859         } else
1860 #endif
1861                 status = finish_device_resume(udev);
1862         if (status < 0)
1863                 dev_dbg(&udev->dev, "can't resume, status %d\n",
1864                         status);
1865
1866         usb_unlock_device(udev);
1867
1868         /* rebind drivers that had no suspend() */
1869         if (status == 0) {
1870                 usb_lock_all_devices();
1871                 bus_rescan_devices(&usb_bus_type);
1872                 usb_unlock_all_devices();
1873         }
1874         return status;
1875 }
1876
1877 static int remote_wakeup(struct usb_device *udev)
1878 {
1879         int     status = 0;
1880
1881 #ifdef  CONFIG_USB_SUSPEND
1882
1883         /* don't repeat RESUME sequence if this device
1884          * was already woken up by some other task
1885          */
1886         down(&udev->serialize);
1887         if (udev->state == USB_STATE_SUSPENDED) {
1888                 dev_dbg(&udev->dev, "RESUME (wakeup)\n");
1889                 /* TRSMRCY = 10 msec */
1890                 msleep(10);
1891                 status = finish_device_resume(udev);
1892         }
1893         up(&udev->serialize);
1894 #endif
1895         return status;
1896 }
1897
1898 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
1899 {
1900         struct usb_hub          *hub = usb_get_intfdata (intf);
1901         struct usb_device       *hdev = hub->hdev;
1902         unsigned                port1;
1903
1904         /* fail if children aren't already suspended */
1905         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1906                 struct usb_device       *udev;
1907
1908                 udev = hdev->children [port1-1];
1909                 if (udev && (udev->dev.power.power_state.event
1910                                         == PM_EVENT_ON
1911 #ifdef  CONFIG_USB_SUSPEND
1912                                 || udev->state != USB_STATE_SUSPENDED
1913 #endif
1914                                 )) {
1915                         dev_dbg(&intf->dev, "port %d nyet suspended\n", port1);
1916                         return -EBUSY;
1917                 }
1918         }
1919
1920         /* "global suspend" of the downstream HC-to-USB interface */
1921         if (!hdev->parent) {
1922                 struct usb_bus  *bus = hdev->bus;
1923                 if (bus) {
1924                         int     status = hcd_bus_suspend (bus);
1925
1926                         if (status != 0) {
1927                                 dev_dbg(&hdev->dev, "'global' suspend %d\n",
1928                                         status);
1929                                 return status;
1930                         }
1931                 } else
1932                         return -EOPNOTSUPP;
1933         }
1934
1935         /* stop khubd and related activity */
1936         hub_quiesce(hub);
1937         return 0;
1938 }
1939
1940 static int hub_resume(struct usb_interface *intf)
1941 {
1942         struct usb_device       *hdev = interface_to_usbdev(intf);
1943         struct usb_hub          *hub = usb_get_intfdata (intf);
1944         int                     status;
1945
1946         /* "global resume" of the downstream HC-to-USB interface */
1947         if (!hdev->parent) {
1948                 struct usb_bus  *bus = hdev->bus;
1949                 if (bus) {
1950                         status = hcd_bus_resume (bus);
1951                         if (status) {
1952                                 dev_dbg(&intf->dev, "'global' resume %d\n",
1953                                         status);
1954                                 return status;
1955                         }
1956                 } else
1957                         return -EOPNOTSUPP;
1958                 if (status == 0) {
1959                         /* TRSMRCY = 10 msec */
1960                         msleep(10);
1961                 }
1962         }
1963
1964         hub_activate(hub);
1965
1966         /* REVISIT:  this recursion probably shouldn't exist.  Remove
1967          * this code sometime, after retesting with different root and
1968          * external hubs.
1969          */
1970 #ifdef  CONFIG_USB_SUSPEND
1971         {
1972         unsigned                port1;
1973
1974         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1975                 struct usb_device       *udev;
1976                 u16                     portstat, portchange;
1977
1978                 udev = hdev->children [port1-1];
1979                 status = hub_port_status(hub, port1, &portstat, &portchange);
1980                 if (status == 0) {
1981                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
1982                                 clear_port_feature(hdev, port1,
1983                                         USB_PORT_FEAT_C_SUSPEND);
1984                                 portchange &= ~USB_PORT_STAT_C_SUSPEND;
1985                         }
1986
1987                         /* let khubd handle disconnects etc */
1988                         if (portchange)
1989                                 continue;
1990                 }
1991
1992                 if (!udev || status < 0)
1993                         continue;
1994                 down (&udev->serialize);
1995                 if (portstat & USB_PORT_STAT_SUSPEND)
1996                         status = hub_port_resume(hub, port1, udev);
1997                 else {
1998                         status = finish_device_resume(udev);
1999                         if (status < 0) {
2000                                 dev_dbg(&intf->dev, "resume port %d --> %d\n",
2001                                         port1, status);
2002                                 hub_port_logical_disconnect(hub, port1);
2003                         }
2004                 }
2005                 up(&udev->serialize);
2006         }
2007         }
2008 #endif
2009         return 0;
2010 }
2011
2012 void usb_suspend_root_hub(struct usb_device *hdev)
2013 {
2014         struct usb_hub *hub = hdev_to_hub(hdev);
2015
2016         /* This also makes any led blinker stop retriggering.  We're called
2017          * from irq, so the blinker might still be scheduled.  Caller promises
2018          * that the root hub status URB will be canceled.
2019          */
2020         __hub_quiesce(hub);
2021         mark_quiesced(to_usb_interface(hub->intfdev));
2022 }
2023
2024 void usb_resume_root_hub(struct usb_device *hdev)
2025 {
2026         struct usb_hub *hub = hdev_to_hub(hdev);
2027
2028         hub->resume_root_hub = 1;
2029         kick_khubd(hub);
2030 }
2031
2032
2033 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
2034  *
2035  * Between connect detection and reset signaling there must be a delay
2036  * of 100ms at least for debounce and power-settling.  The corresponding
2037  * timer shall restart whenever the downstream port detects a disconnect.
2038  * 
2039  * Apparently there are some bluetooth and irda-dongles and a number of
2040  * low-speed devices for which this debounce period may last over a second.
2041  * Not covered by the spec - but easy to deal with.
2042  *
2043  * This implementation uses a 1500ms total debounce timeout; if the
2044  * connection isn't stable by then it returns -ETIMEDOUT.  It checks
2045  * every 25ms for transient disconnects.  When the port status has been
2046  * unchanged for 100ms it returns the port status.
2047  */
2048
2049 #define HUB_DEBOUNCE_TIMEOUT    1500
2050 #define HUB_DEBOUNCE_STEP         25
2051 #define HUB_DEBOUNCE_STABLE      100
2052
2053 static int hub_port_debounce(struct usb_hub *hub, int port1)
2054 {
2055         int ret;
2056         int total_time, stable_time = 0;
2057         u16 portchange, portstatus;
2058         unsigned connection = 0xffff;
2059
2060         for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
2061                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2062                 if (ret < 0)
2063                         return ret;
2064
2065                 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
2066                      (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2067                         stable_time += HUB_DEBOUNCE_STEP;
2068                         if (stable_time >= HUB_DEBOUNCE_STABLE)
2069                                 break;
2070                 } else {
2071                         stable_time = 0;
2072                         connection = portstatus & USB_PORT_STAT_CONNECTION;
2073                 }
2074
2075                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2076                         clear_port_feature(hub->hdev, port1,
2077                                         USB_PORT_FEAT_C_CONNECTION);
2078                 }
2079
2080                 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2081                         break;
2082                 msleep(HUB_DEBOUNCE_STEP);
2083         }
2084
2085         dev_dbg (hub->intfdev,
2086                 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2087                 port1, total_time, stable_time, portstatus);
2088
2089         if (stable_time < HUB_DEBOUNCE_STABLE)
2090                 return -ETIMEDOUT;
2091         return portstatus;
2092 }
2093
2094 static void ep0_reinit(struct usb_device *udev)
2095 {
2096         usb_disable_endpoint(udev, 0 + USB_DIR_IN);
2097         usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
2098         udev->ep_in[0] = udev->ep_out[0] = &udev->ep0;
2099 }
2100
2101 #define usb_sndaddr0pipe()      (PIPE_CONTROL << 30)
2102 #define usb_rcvaddr0pipe()      ((PIPE_CONTROL << 30) | USB_DIR_IN)
2103
2104 static int hub_set_address(struct usb_device *udev)
2105 {
2106         int retval;
2107
2108         if (udev->devnum == 0)
2109                 return -EINVAL;
2110         if (udev->state == USB_STATE_ADDRESS)
2111                 return 0;
2112         if (udev->state != USB_STATE_DEFAULT)
2113                 return -EINVAL;
2114         retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2115                 USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
2116                 NULL, 0, USB_CTRL_SET_TIMEOUT);
2117         if (retval == 0) {
2118                 usb_set_device_state(udev, USB_STATE_ADDRESS);
2119                 ep0_reinit(udev);
2120         }
2121         return retval;
2122 }
2123
2124 /* Reset device, (re)assign address, get device descriptor.
2125  * Device connection must be stable, no more debouncing needed.
2126  * Returns device in USB_STATE_ADDRESS, except on error.
2127  *
2128  * If this is called for an already-existing device (as part of
2129  * usb_reset_device), the caller must own the device lock.  For a
2130  * newly detected device that is not accessible through any global
2131  * pointers, it's not necessary to lock the device.
2132  */
2133 static int
2134 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2135                 int retry_counter)
2136 {
2137         static DECLARE_MUTEX(usb_address0_sem);
2138
2139         struct usb_device       *hdev = hub->hdev;
2140         int                     i, j, retval;
2141         unsigned                delay = HUB_SHORT_RESET_TIME;
2142         enum usb_device_speed   oldspeed = udev->speed;
2143
2144         /* root hub ports have a slightly longer reset period
2145          * (from USB 2.0 spec, section 7.1.7.5)
2146          */
2147         if (!hdev->parent) {
2148                 delay = HUB_ROOT_RESET_TIME;
2149                 if (port1 == hdev->bus->otg_port)
2150                         hdev->bus->b_hnp_enable = 0;
2151         }
2152
2153         /* Some low speed devices have problems with the quick delay, so */
2154         /*  be a bit pessimistic with those devices. RHbug #23670 */
2155         if (oldspeed == USB_SPEED_LOW)
2156                 delay = HUB_LONG_RESET_TIME;
2157
2158         down(&usb_address0_sem);
2159
2160         /* Reset the device; full speed may morph to high speed */
2161         retval = hub_port_reset(hub, port1, udev, delay);
2162         if (retval < 0)         /* error or disconnect */
2163                 goto fail;
2164                                 /* success, speed is known */
2165         retval = -ENODEV;
2166
2167         if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2168                 dev_dbg(&udev->dev, "device reset changed speed!\n");
2169                 goto fail;
2170         }
2171         oldspeed = udev->speed;
2172   
2173         /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2174          * it's fixed size except for full speed devices.
2175          */
2176         switch (udev->speed) {
2177         case USB_SPEED_HIGH:            /* fixed at 64 */
2178                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2179                 break;
2180         case USB_SPEED_FULL:            /* 8, 16, 32, or 64 */
2181                 /* to determine the ep0 maxpacket size, try to read
2182                  * the device descriptor to get bMaxPacketSize0 and
2183                  * then correct our initial guess.
2184                  */
2185                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2186                 break;
2187         case USB_SPEED_LOW:             /* fixed at 8 */
2188                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
2189                 break;
2190         default:
2191                 goto fail;
2192         }
2193  
2194         dev_info (&udev->dev,
2195                         "%s %s speed USB device using %s and address %d\n",
2196                         (udev->config) ? "reset" : "new",
2197                         ({ char *speed; switch (udev->speed) {
2198                         case USB_SPEED_LOW:     speed = "low";  break;
2199                         case USB_SPEED_FULL:    speed = "full"; break;
2200                         case USB_SPEED_HIGH:    speed = "high"; break;
2201                         default:                speed = "?";    break;
2202                         }; speed;}),
2203                         udev->bus->controller->driver->name,
2204                         udev->devnum);
2205
2206         /* Set up TT records, if needed  */
2207         if (hdev->tt) {
2208                 udev->tt = hdev->tt;
2209                 udev->ttport = hdev->ttport;
2210         } else if (udev->speed != USB_SPEED_HIGH
2211                         && hdev->speed == USB_SPEED_HIGH) {
2212                 udev->tt = &hub->tt;
2213                 udev->ttport = port1;
2214         }
2215  
2216         /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2217          * Because device hardware and firmware is sometimes buggy in
2218          * this area, and this is how Linux has done it for ages.
2219          * Change it cautiously.
2220          *
2221          * NOTE:  If USE_NEW_SCHEME() is true we will start by issuing
2222          * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
2223          * so it may help with some non-standards-compliant devices.
2224          * Otherwise we start with SET_ADDRESS and then try to read the
2225          * first 8 bytes of the device descriptor to get the ep0 maxpacket
2226          * value.
2227          */
2228         for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2229                 if (USE_NEW_SCHEME(retry_counter)) {
2230                         struct usb_device_descriptor *buf;
2231                         int r = 0;
2232
2233 #define GET_DESCRIPTOR_BUFSIZE  64
2234                         buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2235                         if (!buf) {
2236                                 retval = -ENOMEM;
2237                                 continue;
2238                         }
2239
2240                         /* Use a short timeout the first time through,
2241                          * so that recalcitrant full-speed devices with
2242                          * 8- or 16-byte ep0-maxpackets won't slow things
2243                          * down tremendously by NAKing the unexpectedly
2244                          * early status stage.  Also, retry on all errors;
2245                          * some devices are flakey.
2246                          */
2247                         for (j = 0; j < 3; ++j) {
2248                                 buf->bMaxPacketSize0 = 0;
2249                                 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2250                                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2251                                         USB_DT_DEVICE << 8, 0,
2252                                         buf, GET_DESCRIPTOR_BUFSIZE,
2253                                         (i ? USB_CTRL_GET_TIMEOUT : 1000));
2254                                 switch (buf->bMaxPacketSize0) {
2255                                 case 8: case 16: case 32: case 64:
2256                                         if (buf->bDescriptorType ==
2257                                                         USB_DT_DEVICE) {
2258                                                 r = 0;
2259                                                 break;
2260                                         }
2261                                         /* FALL THROUGH */
2262                                 default:
2263                                         if (r == 0)
2264                                                 r = -EPROTO;
2265                                         break;
2266                                 }
2267                                 if (r == 0)
2268                                         break;
2269                         }
2270                         udev->descriptor.bMaxPacketSize0 =
2271                                         buf->bMaxPacketSize0;
2272                         kfree(buf);
2273
2274                         retval = hub_port_reset(hub, port1, udev, delay);
2275                         if (retval < 0)         /* error or disconnect */
2276                                 goto fail;
2277                         if (oldspeed != udev->speed) {
2278                                 dev_dbg(&udev->dev,
2279                                         "device reset changed speed!\n");
2280                                 retval = -ENODEV;
2281                                 goto fail;
2282                         }
2283                         if (r) {
2284                                 dev_err(&udev->dev, "device descriptor "
2285                                                 "read/%s, error %d\n",
2286                                                 "64", r);
2287                                 retval = -EMSGSIZE;
2288                                 continue;
2289                         }
2290 #undef GET_DESCRIPTOR_BUFSIZE
2291                 }
2292
2293                 for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2294                         retval = hub_set_address(udev);
2295                         if (retval >= 0)
2296                                 break;
2297                         msleep(200);
2298                 }
2299                 if (retval < 0) {
2300                         dev_err(&udev->dev,
2301                                 "device not accepting address %d, error %d\n",
2302                                 udev->devnum, retval);
2303                         goto fail;
2304                 }
2305  
2306                 /* cope with hardware quirkiness:
2307                  *  - let SET_ADDRESS settle, some device hardware wants it
2308                  *  - read ep0 maxpacket even for high and low speed,
2309                  */
2310                 msleep(10);
2311                 if (USE_NEW_SCHEME(retry_counter))
2312                         break;
2313
2314                 retval = usb_get_device_descriptor(udev, 8);
2315                 if (retval < 8) {
2316                         dev_err(&udev->dev, "device descriptor "
2317                                         "read/%s, error %d\n",
2318                                         "8", retval);
2319                         if (retval >= 0)
2320                                 retval = -EMSGSIZE;
2321                 } else {
2322                         retval = 0;
2323                         break;
2324                 }
2325         }
2326         if (retval)
2327                 goto fail;
2328
2329         i = udev->descriptor.bMaxPacketSize0;
2330         if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2331                 if (udev->speed != USB_SPEED_FULL ||
2332                                 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2333                         dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
2334                         retval = -EMSGSIZE;
2335                         goto fail;
2336                 }
2337                 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2338                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2339                 ep0_reinit(udev);
2340         }
2341   
2342         retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2343         if (retval < (signed)sizeof(udev->descriptor)) {
2344                 dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
2345                         "all", retval);
2346                 if (retval >= 0)
2347                         retval = -ENOMSG;
2348                 goto fail;
2349         }
2350
2351         retval = 0;
2352
2353 fail:
2354         if (retval)
2355                 hub_port_disable(hub, port1, 0);
2356         up(&usb_address0_sem);
2357         return retval;
2358 }
2359
2360 static void
2361 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2362 {
2363         struct usb_qualifier_descriptor *qual;
2364         int                             status;
2365
2366         qual = kmalloc (sizeof *qual, SLAB_KERNEL);
2367         if (qual == NULL)
2368                 return;
2369
2370         status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2371                         qual, sizeof *qual);
2372         if (status == sizeof *qual) {
2373                 dev_info(&udev->dev, "not running at top speed; "
2374                         "connect to a high speed hub\n");
2375                 /* hub LEDs are probably harder to miss than syslog */
2376                 if (hub->has_indicators) {
2377                         hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2378                         schedule_work (&hub->leds);
2379                 }
2380         }
2381         kfree(qual);
2382 }
2383
2384 static unsigned
2385 hub_power_remaining (struct usb_hub *hub)
2386 {
2387         struct usb_device *hdev = hub->hdev;
2388         int remaining;
2389         unsigned i;
2390
2391         remaining = hub->power_budget;
2392         if (!remaining)         /* self-powered */
2393                 return 0;
2394
2395         for (i = 0; i < hdev->maxchild; i++) {
2396                 struct usb_device       *udev = hdev->children[i];
2397                 int                     delta, ceiling;
2398
2399                 if (!udev)
2400                         continue;
2401
2402                 /* 100mA per-port ceiling, or 8mA for OTG ports */
2403                 if (i != (udev->bus->otg_port - 1) || hdev->parent)
2404                         ceiling = 50;
2405                 else
2406                         ceiling = 4;
2407
2408                 if (udev->actconfig)
2409                         delta = udev->actconfig->desc.bMaxPower;
2410                 else
2411                         delta = ceiling;
2412                 // dev_dbg(&udev->dev, "budgeted %dmA\n", 2 * delta);
2413                 if (delta > ceiling)
2414                         dev_warn(&udev->dev, "%dmA over %dmA budget!\n",
2415                                 2 * (delta - ceiling), 2 * ceiling);
2416                 remaining -= delta;
2417         }
2418         if (remaining < 0) {
2419                 dev_warn(hub->intfdev,
2420                         "%dmA over power budget!\n",
2421                         -2 * remaining);
2422                 remaining = 0;
2423         }
2424         return remaining;
2425 }
2426
2427 /* Handle physical or logical connection change events.
2428  * This routine is called when:
2429  *      a port connection-change occurs;
2430  *      a port enable-change occurs (often caused by EMI);
2431  *      usb_reset_device() encounters changed descriptors (as from
2432  *              a firmware download)
2433  * caller already locked the hub
2434  */
2435 static void hub_port_connect_change(struct usb_hub *hub, int port1,
2436                                         u16 portstatus, u16 portchange)
2437 {
2438         struct usb_device *hdev = hub->hdev;
2439         struct device *hub_dev = hub->intfdev;
2440         u16 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
2441         int status, i;
2442  
2443         dev_dbg (hub_dev,
2444                 "port %d, status %04x, change %04x, %s\n",
2445                 port1, portstatus, portchange, portspeed (portstatus));
2446
2447         if (hub->has_indicators) {
2448                 set_port_led(hub, port1, HUB_LED_AUTO);
2449                 hub->indicator[port1-1] = INDICATOR_AUTO;
2450         }
2451  
2452         /* Disconnect any existing devices under this port */
2453         if (hdev->children[port1-1])
2454                 usb_disconnect(&hdev->children[port1-1]);
2455         clear_bit(port1, hub->change_bits);
2456
2457 #ifdef  CONFIG_USB_OTG
2458         /* during HNP, don't repeat the debounce */
2459         if (hdev->bus->is_b_host)
2460                 portchange &= ~USB_PORT_STAT_C_CONNECTION;
2461 #endif
2462
2463         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2464                 status = hub_port_debounce(hub, port1);
2465                 if (status < 0) {
2466                         dev_err (hub_dev,
2467                                 "connect-debounce failed, port %d disabled\n",
2468                                 port1);
2469                         goto done;
2470                 }
2471                 portstatus = status;
2472         }
2473
2474         /* Return now if nothing is connected */
2475         if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2476
2477                 /* maybe switch power back on (e.g. root hub was reset) */
2478                 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2
2479                                 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
2480                         set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
2481  
2482                 if (portstatus & USB_PORT_STAT_ENABLE)
2483                         goto done;
2484                 return;
2485         }
2486
2487 #ifdef  CONFIG_USB_SUSPEND
2488         /* If something is connected, but the port is suspended, wake it up. */
2489         if (portstatus & USB_PORT_STAT_SUSPEND) {
2490                 status = hub_port_resume(hub, port1, NULL);
2491                 if (status < 0) {
2492                         dev_dbg(hub_dev,
2493                                 "can't clear suspend on port %d; %d\n",
2494                                 port1, status);
2495                         goto done;
2496                 }
2497         }
2498 #endif
2499
2500         for (i = 0; i < SET_CONFIG_TRIES; i++) {
2501                 struct usb_device *udev;
2502
2503                 /* reallocate for each attempt, since references
2504                  * to the previous one can escape in various ways
2505                  */
2506                 udev = usb_alloc_dev(hdev, hdev->bus, port1);
2507                 if (!udev) {
2508                         dev_err (hub_dev,
2509                                 "couldn't allocate port %d usb_device\n",
2510                                 port1);
2511                         goto done;
2512                 }
2513
2514                 usb_set_device_state(udev, USB_STATE_POWERED);
2515                 udev->speed = USB_SPEED_UNKNOWN;
2516  
2517                 /* set the address */
2518                 choose_address(udev);
2519                 if (udev->devnum <= 0) {
2520                         status = -ENOTCONN;     /* Don't retry */
2521                         goto loop;
2522                 }
2523
2524                 /* reset and get descriptor */
2525                 status = hub_port_init(hub, udev, port1, i);
2526                 if (status < 0)
2527                         goto loop;
2528
2529                 /* consecutive bus-powered hubs aren't reliable; they can
2530                  * violate the voltage drop budget.  if the new child has
2531                  * a "powered" LED, users should notice we didn't enable it
2532                  * (without reading syslog), even without per-port LEDs
2533                  * on the parent.
2534                  */
2535                 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
2536                                 && hub->power_budget) {
2537                         u16     devstat;
2538
2539                         status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
2540                                         &devstat);
2541                         if (status < 0) {
2542                                 dev_dbg(&udev->dev, "get status %d ?\n", status);
2543                                 goto loop_disable;
2544                         }
2545                         cpu_to_le16s(&devstat);
2546                         if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
2547                                 dev_err(&udev->dev,
2548                                         "can't connect bus-powered hub "
2549                                         "to this port\n");
2550                                 if (hub->has_indicators) {
2551                                         hub->indicator[port1-1] =
2552                                                 INDICATOR_AMBER_BLINK;
2553                                         schedule_work (&hub->leds);
2554                                 }
2555                                 status = -ENOTCONN;     /* Don't retry */
2556                                 goto loop_disable;
2557                         }
2558                 }
2559  
2560                 /* check for devices running slower than they could */
2561                 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
2562                                 && udev->speed == USB_SPEED_FULL
2563                                 && highspeed_hubs != 0)
2564                         check_highspeed (hub, udev, port1);
2565
2566                 /* Store the parent's children[] pointer.  At this point
2567                  * udev becomes globally accessible, although presumably
2568                  * no one will look at it until hdev is unlocked.
2569                  */
2570                 down (&udev->serialize);
2571                 status = 0;
2572
2573                 /* We mustn't add new devices if the parent hub has
2574                  * been disconnected; we would race with the
2575                  * recursively_mark_NOTATTACHED() routine.
2576                  */
2577                 spin_lock_irq(&device_state_lock);
2578                 if (hdev->state == USB_STATE_NOTATTACHED)
2579                         status = -ENOTCONN;
2580                 else
2581                         hdev->children[port1-1] = udev;
2582                 spin_unlock_irq(&device_state_lock);
2583
2584                 /* Run it through the hoops (find a driver, etc) */
2585                 if (!status) {
2586                         status = usb_new_device(udev);
2587                         if (status) {
2588                                 spin_lock_irq(&device_state_lock);
2589                                 hdev->children[port1-1] = NULL;
2590                                 spin_unlock_irq(&device_state_lock);
2591                         }
2592                 }
2593
2594                 up (&udev->serialize);
2595                 if (status)
2596                         goto loop_disable;
2597
2598                 status = hub_power_remaining(hub);
2599                 if (status)
2600                         dev_dbg(hub_dev,
2601                                 "%dmA power budget left\n",
2602                                 2 * status);
2603
2604                 return;
2605
2606 loop_disable:
2607                 hub_port_disable(hub, port1, 1);
2608 loop:
2609                 ep0_reinit(udev);
2610                 release_address(udev);
2611                 usb_put_dev(udev);
2612                 if (status == -ENOTCONN)
2613                         break;
2614         }
2615  
2616 done:
2617         hub_port_disable(hub, port1, 1);
2618 }
2619
2620 static void hub_events(void)
2621 {
2622         struct list_head *tmp;
2623         struct usb_device *hdev;
2624         struct usb_interface *intf;
2625         struct usb_hub *hub;
2626         struct device *hub_dev;
2627         u16 hubstatus;
2628         u16 hubchange;
2629         u16 portstatus;
2630         u16 portchange;
2631         int i, ret;
2632         int connect_change;
2633
2634         /*
2635          *  We restart the list every time to avoid a deadlock with
2636          * deleting hubs downstream from this one. This should be
2637          * safe since we delete the hub from the event list.
2638          * Not the most efficient, but avoids deadlocks.
2639          */
2640         while (1) {
2641
2642                 /* Grab the first entry at the beginning of the list */
2643                 spin_lock_irq(&hub_event_lock);
2644                 if (list_empty(&hub_event_list)) {
2645                         spin_unlock_irq(&hub_event_lock);
2646                         break;
2647                 }
2648
2649                 tmp = hub_event_list.next;
2650                 list_del_init(tmp);
2651
2652                 hub = list_entry(tmp, struct usb_hub, event_list);
2653                 hdev = hub->hdev;
2654                 intf = to_usb_interface(hub->intfdev);
2655                 hub_dev = &intf->dev;
2656
2657                 i = hub->resume_root_hub;
2658
2659                 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x%s\n",
2660                                 hdev->state, hub->descriptor
2661                                         ? hub->descriptor->bNbrPorts
2662                                         : 0,
2663                                 /* NOTE: expects max 15 ports... */
2664                                 (u16) hub->change_bits[0],
2665                                 (u16) hub->event_bits[0],
2666                                 i ? ", resume root" : "");
2667
2668                 usb_get_intf(intf);
2669                 spin_unlock_irq(&hub_event_lock);
2670
2671                 /* Is this is a root hub wanting to reactivate the downstream
2672                  * ports?  If so, be sure the interface resumes even if its
2673                  * stub "device" node was never suspended.
2674                  */
2675                 if (i) {
2676                         extern void dpm_runtime_resume(struct device *);
2677
2678                         dpm_runtime_resume(&hdev->dev);
2679                         dpm_runtime_resume(&intf->dev);
2680                 }
2681
2682                 /* Lock the device, then check to see if we were
2683                  * disconnected while waiting for the lock to succeed. */
2684                 if (locktree(hdev) < 0) {
2685                         usb_put_intf(intf);
2686                         continue;
2687                 }
2688                 if (hub != usb_get_intfdata(intf))
2689                         goto loop;
2690
2691                 /* If the hub has died, clean up after it */
2692                 if (hdev->state == USB_STATE_NOTATTACHED) {
2693                         hub_pre_reset(hub);
2694                         goto loop;
2695                 }
2696
2697                 /* If this is an inactive or suspended hub, do nothing */
2698                 if (hub->quiescing)
2699                         goto loop;
2700
2701                 if (hub->error) {
2702                         dev_dbg (hub_dev, "resetting for error %d\n",
2703                                 hub->error);
2704
2705                         ret = usb_reset_device(hdev);
2706                         if (ret) {
2707                                 dev_dbg (hub_dev,
2708                                         "error resetting hub: %d\n", ret);
2709                                 goto loop;
2710                         }
2711
2712                         hub->nerrors = 0;
2713                         hub->error = 0;
2714                 }
2715
2716                 /* deal with port status changes */
2717                 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
2718                         if (test_bit(i, hub->busy_bits))
2719                                 continue;
2720                         connect_change = test_bit(i, hub->change_bits);
2721                         if (!test_and_clear_bit(i, hub->event_bits) &&
2722                                         !connect_change && !hub->activating)
2723                                 continue;
2724
2725                         ret = hub_port_status(hub, i,
2726                                         &portstatus, &portchange);
2727                         if (ret < 0)
2728                                 continue;
2729
2730                         if (hub->activating && !hdev->children[i-1] &&
2731                                         (portstatus &
2732                                                 USB_PORT_STAT_CONNECTION))
2733                                 connect_change = 1;
2734
2735                         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2736                                 clear_port_feature(hdev, i,
2737                                         USB_PORT_FEAT_C_CONNECTION);
2738                                 connect_change = 1;
2739                         }
2740
2741                         if (portchange & USB_PORT_STAT_C_ENABLE) {
2742                                 if (!connect_change)
2743                                         dev_dbg (hub_dev,
2744                                                 "port %d enable change, "
2745                                                 "status %08x\n",
2746                                                 i, portstatus);
2747                                 clear_port_feature(hdev, i,
2748                                         USB_PORT_FEAT_C_ENABLE);
2749
2750                                 /*
2751                                  * EM interference sometimes causes badly
2752                                  * shielded USB devices to be shutdown by
2753                                  * the hub, this hack enables them again.
2754                                  * Works at least with mouse driver. 
2755                                  */
2756                                 if (!(portstatus & USB_PORT_STAT_ENABLE)
2757                                     && !connect_change
2758                                     && hdev->children[i-1]) {
2759                                         dev_err (hub_dev,
2760                                             "port %i "
2761                                             "disabled by hub (EMI?), "
2762                                             "re-enabling...\n",
2763                                                 i);
2764                                         connect_change = 1;
2765                                 }
2766                         }
2767
2768                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
2769                                 clear_port_feature(hdev, i,
2770                                         USB_PORT_FEAT_C_SUSPEND);
2771                                 if (hdev->children[i-1]) {
2772                                         ret = remote_wakeup(hdev->
2773                                                         children[i-1]);
2774                                         if (ret < 0)
2775                                                 connect_change = 1;
2776                                 } else {
2777                                         ret = -ENODEV;
2778                                         hub_port_disable(hub, i, 1);
2779                                 }
2780                                 dev_dbg (hub_dev,
2781                                         "resume on port %d, status %d\n",
2782                                         i, ret);
2783                         }
2784                         
2785                         if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
2786                                 dev_err (hub_dev,
2787                                         "over-current change on port %d\n",
2788                                         i);
2789                                 clear_port_feature(hdev, i,
2790                                         USB_PORT_FEAT_C_OVER_CURRENT);
2791                                 hub_power_on(hub);
2792                         }
2793
2794                         if (portchange & USB_PORT_STAT_C_RESET) {
2795                                 dev_dbg (hub_dev,
2796                                         "reset change on port %d\n",
2797                                         i);
2798                                 clear_port_feature(hdev, i,
2799                                         USB_PORT_FEAT_C_RESET);
2800                         }
2801
2802                         if (connect_change)
2803                                 hub_port_connect_change(hub, i,
2804                                                 portstatus, portchange);
2805                 } /* end for i */
2806
2807                 /* deal with hub status changes */
2808                 if (test_and_clear_bit(0, hub->event_bits) == 0)
2809                         ;       /* do nothing */
2810                 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
2811                         dev_err (hub_dev, "get_hub_status failed\n");
2812                 else {
2813                         if (hubchange & HUB_CHANGE_LOCAL_POWER) {
2814                                 dev_dbg (hub_dev, "power change\n");
2815                                 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
2816                         }
2817                         if (hubchange & HUB_CHANGE_OVERCURRENT) {
2818                                 dev_dbg (hub_dev, "overcurrent change\n");
2819                                 msleep(500);    /* Cool down */
2820                                 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
2821                                 hub_power_on(hub);
2822                         }
2823                 }
2824
2825                 hub->activating = 0;
2826
2827                 /* If this is a root hub, tell the HCD it's okay to
2828                  * re-enable port-change interrupts now. */
2829                 if (!hdev->parent)
2830                         usb_enable_root_hub_irq(hdev->bus);
2831
2832 loop:
2833                 usb_unlock_device(hdev);
2834                 usb_put_intf(intf);
2835
2836         } /* end while (1) */
2837 }
2838
2839 static int hub_thread(void *__unused)
2840 {
2841         do {
2842                 hub_events();
2843                 wait_event_interruptible(khubd_wait,
2844                                 !list_empty(&hub_event_list) ||
2845                                 kthread_should_stop());
2846                 try_to_freeze();
2847         } while (!kthread_should_stop() || !list_empty(&hub_event_list));
2848
2849         pr_debug("%s: khubd exiting\n", usbcore_name);
2850         return 0;
2851 }
2852
2853 static struct usb_device_id hub_id_table [] = {
2854     { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
2855       .bDeviceClass = USB_CLASS_HUB},
2856     { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
2857       .bInterfaceClass = USB_CLASS_HUB},
2858     { }                                         /* Terminating entry */
2859 };
2860
2861 MODULE_DEVICE_TABLE (usb, hub_id_table);
2862
2863 static struct usb_driver hub_driver = {
2864         .owner =        THIS_MODULE,
2865         .name =         "hub",
2866         .probe =        hub_probe,
2867         .disconnect =   hub_disconnect,
2868         .suspend =      hub_suspend,
2869         .resume =       hub_resume,
2870         .ioctl =        hub_ioctl,
2871         .id_table =     hub_id_table,
2872 };
2873
2874 int usb_hub_init(void)
2875 {
2876         if (usb_register(&hub_driver) < 0) {
2877                 printk(KERN_ERR "%s: can't register hub driver\n",
2878                         usbcore_name);
2879                 return -1;
2880         }
2881
2882         khubd_task = kthread_run(hub_thread, NULL, "khubd");
2883         if (!IS_ERR(khubd_task))
2884                 return 0;
2885
2886         /* Fall through if kernel_thread failed */
2887         usb_deregister(&hub_driver);
2888         printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
2889
2890         return -1;
2891 }
2892
2893 void usb_hub_cleanup(void)
2894 {
2895         kthread_stop(khubd_task);
2896
2897         /*
2898          * Hub resources are freed for us by usb_deregister. It calls
2899          * usb_driver_purge on every device which in turn calls that
2900          * devices disconnect function if it is using this driver.
2901          * The hub_disconnect function takes care of releasing the
2902          * individual hub resources. -greg
2903          */
2904         usb_deregister(&hub_driver);
2905 } /* usb_hub_cleanup() */
2906
2907 static int config_descriptors_changed(struct usb_device *udev)
2908 {
2909         unsigned                        index;
2910         unsigned                        len = 0;
2911         struct usb_config_descriptor    *buf;
2912
2913         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2914                 if (len < le16_to_cpu(udev->config[index].desc.wTotalLength))
2915                         len = le16_to_cpu(udev->config[index].desc.wTotalLength);
2916         }
2917         buf = kmalloc (len, SLAB_KERNEL);
2918         if (buf == NULL) {
2919                 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
2920                 /* assume the worst */
2921                 return 1;
2922         }
2923         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2924                 int length;
2925                 int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
2926
2927                 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
2928                                 old_length);
2929                 if (length < old_length) {
2930                         dev_dbg(&udev->dev, "config index %d, error %d\n",
2931                                         index, length);
2932                         break;
2933                 }
2934                 if (memcmp (buf, udev->rawdescriptors[index], old_length)
2935                                 != 0) {
2936                         dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
2937                                 index, buf->bConfigurationValue);
2938                         break;
2939                 }
2940         }
2941         kfree(buf);
2942         return index != udev->descriptor.bNumConfigurations;
2943 }
2944
2945 /**
2946  * usb_reset_device - perform a USB port reset to reinitialize a device
2947  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2948  *
2949  * WARNING - don't reset any device unless drivers for all of its
2950  * interfaces are expecting that reset!  Maybe some driver->reset()
2951  * method should eventually help ensure sufficient cooperation.
2952  *
2953  * Do a port reset, reassign the device's address, and establish its
2954  * former operating configuration.  If the reset fails, or the device's
2955  * descriptors change from their values before the reset, or the original
2956  * configuration and altsettings cannot be restored, a flag will be set
2957  * telling khubd to pretend the device has been disconnected and then
2958  * re-connected.  All drivers will be unbound, and the device will be
2959  * re-enumerated and probed all over again.
2960  *
2961  * Returns 0 if the reset succeeded, -ENODEV if the device has been
2962  * flagged for logical disconnection, or some other negative error code
2963  * if the reset wasn't even attempted.
2964  *
2965  * The caller must own the device lock.  For example, it's safe to use
2966  * this from a driver probe() routine after downloading new firmware.
2967  * For calls that might not occur during probe(), drivers should lock
2968  * the device using usb_lock_device_for_reset().
2969  */
2970 int usb_reset_device(struct usb_device *udev)
2971 {
2972         struct usb_device               *parent_hdev = udev->parent;
2973         struct usb_hub                  *parent_hub;
2974         struct usb_device_descriptor    descriptor = udev->descriptor;
2975         struct usb_hub                  *hub = NULL;
2976         int                             i, ret = 0, port1 = -1;
2977
2978         if (udev->state == USB_STATE_NOTATTACHED ||
2979                         udev->state == USB_STATE_SUSPENDED) {
2980                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
2981                                 udev->state);
2982                 return -EINVAL;
2983         }
2984
2985         if (!parent_hdev) {
2986                 /* this requires hcd-specific logic; see OHCI hc_restart() */
2987                 dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
2988                 return -EISDIR;
2989         }
2990
2991         for (i = 0; i < parent_hdev->maxchild; i++)
2992                 if (parent_hdev->children[i] == udev) {
2993                         port1 = i + 1;
2994                         break;
2995                 }
2996
2997         if (port1 < 0) {
2998                 /* If this ever happens, it's very bad */
2999                 dev_err(&udev->dev, "Can't locate device's port!\n");
3000                 return -ENOENT;
3001         }
3002         parent_hub = hdev_to_hub(parent_hdev);
3003
3004         /* If we're resetting an active hub, take some special actions */
3005         if (udev->actconfig &&
3006                         udev->actconfig->interface[0]->dev.driver ==
3007                                 &hub_driver.driver &&
3008                         (hub = hdev_to_hub(udev)) != NULL) {
3009                 hub_pre_reset(hub);
3010         }
3011
3012         set_bit(port1, parent_hub->busy_bits);
3013         for (i = 0; i < SET_CONFIG_TRIES; ++i) {
3014
3015                 /* ep0 maxpacket size may change; let the HCD know about it.
3016                  * Other endpoints will be handled by re-enumeration. */
3017                 ep0_reinit(udev);
3018                 ret = hub_port_init(parent_hub, udev, port1, i);
3019                 if (ret >= 0)
3020                         break;
3021         }
3022         clear_bit(port1, parent_hub->busy_bits);
3023         if (ret < 0)
3024                 goto re_enumerate;
3025  
3026         /* Device might have changed firmware (DFU or similar) */
3027         if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
3028                         || config_descriptors_changed (udev)) {
3029                 dev_info(&udev->dev, "device firmware changed\n");
3030                 udev->descriptor = descriptor;  /* for disconnect() calls */
3031                 goto re_enumerate;
3032         }
3033   
3034         if (!udev->actconfig)
3035                 goto done;
3036
3037         ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3038                         USB_REQ_SET_CONFIGURATION, 0,
3039                         udev->actconfig->desc.bConfigurationValue, 0,
3040                         NULL, 0, USB_CTRL_SET_TIMEOUT);
3041         if (ret < 0) {
3042                 dev_err(&udev->dev,
3043                         "can't restore configuration #%d (error=%d)\n",
3044                         udev->actconfig->desc.bConfigurationValue, ret);
3045                 goto re_enumerate;
3046         }
3047         usb_set_device_state(udev, USB_STATE_CONFIGURED);
3048
3049         for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
3050                 struct usb_interface *intf = udev->actconfig->interface[i];
3051                 struct usb_interface_descriptor *desc;
3052
3053                 /* set_interface resets host side toggle even
3054                  * for altsetting zero.  the interface may have no driver.
3055                  */
3056                 desc = &intf->cur_altsetting->desc;
3057                 ret = usb_set_interface(udev, desc->bInterfaceNumber,
3058                         desc->bAlternateSetting);
3059                 if (ret < 0) {
3060                         dev_err(&udev->dev, "failed to restore interface %d "
3061                                 "altsetting %d (error=%d)\n",
3062                                 desc->bInterfaceNumber,
3063                                 desc->bAlternateSetting,
3064                                 ret);
3065                         goto re_enumerate;
3066                 }
3067         }
3068
3069 done:
3070         if (hub)
3071                 hub_post_reset(hub);
3072         return 0;
3073  
3074 re_enumerate:
3075         hub_port_logical_disconnect(parent_hub, port1);
3076         return -ENODEV;
3077 }