c4cdb69a6e9ebe91dbf5287c25cf703b35d47838
[safe/jmp/linux-2.6] / drivers / usb / core / hub.c
1 /*
2  * USB hub driver.
3  *
4  * (C) Copyright 1999 Linus Torvalds
5  * (C) Copyright 1999 Johannes Erdfelt
6  * (C) Copyright 1999 Gregory P. Smith
7  * (C) Copyright 2001 Brad Hards (bhards@bigpond.net.au)
8  *
9  */
10
11 #include <linux/kernel.h>
12 #include <linux/errno.h>
13 #include <linux/module.h>
14 #include <linux/moduleparam.h>
15 #include <linux/completion.h>
16 #include <linux/sched.h>
17 #include <linux/list.h>
18 #include <linux/slab.h>
19 #include <linux/ioctl.h>
20 #include <linux/usb.h>
21 #include <linux/usbdevice_fs.h>
22 #include <linux/kthread.h>
23 #include <linux/mutex.h>
24 #include <linux/freezer.h>
25
26 #include <asm/semaphore.h>
27 #include <asm/uaccess.h>
28 #include <asm/byteorder.h>
29
30 #include "usb.h"
31 #include "hcd.h"
32 #include "hub.h"
33
34 #ifdef  CONFIG_USB_PERSIST
35 #define USB_PERSIST     1
36 #else
37 #define USB_PERSIST     0
38 #endif
39
40 struct usb_hub {
41         struct device           *intfdev;       /* the "interface" device */
42         struct usb_device       *hdev;
43         struct kref             kref;
44         struct urb              *urb;           /* for interrupt polling pipe */
45
46         /* buffer for urb ... with extra space in case of babble */
47         char                    (*buffer)[8];
48         dma_addr_t              buffer_dma;     /* DMA address for buffer */
49         union {
50                 struct usb_hub_status   hub;
51                 struct usb_port_status  port;
52         }                       *status;        /* buffer for status reports */
53         struct mutex            status_mutex;   /* for the status buffer */
54
55         int                     error;          /* last reported error */
56         int                     nerrors;        /* track consecutive errors */
57
58         struct list_head        event_list;     /* hubs w/data or errs ready */
59         unsigned long           event_bits[1];  /* status change bitmask */
60         unsigned long           change_bits[1]; /* ports with logical connect
61                                                         status change */
62         unsigned long           busy_bits[1];   /* ports being reset or
63                                                         resumed */
64 #if USB_MAXCHILDREN > 31 /* 8*sizeof(unsigned long) - 1 */
65 #error event_bits[] is too short!
66 #endif
67
68         struct usb_hub_descriptor *descriptor;  /* class descriptor */
69         struct usb_tt           tt;             /* Transaction Translator */
70
71         unsigned                mA_per_port;    /* current for each child */
72
73         unsigned                limited_power:1;
74         unsigned                quiescing:1;
75         unsigned                activating:1;
76         unsigned                disconnected:1;
77
78         unsigned                has_indicators:1;
79         u8                      indicator[USB_MAXCHILDREN];
80         struct delayed_work     leds;
81 };
82
83
84 /* Protect struct usb_device->state and ->children members
85  * Note: Both are also protected by ->dev.sem, except that ->state can
86  * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
87 static DEFINE_SPINLOCK(device_state_lock);
88
89 /* khubd's worklist and its lock */
90 static DEFINE_SPINLOCK(hub_event_lock);
91 static LIST_HEAD(hub_event_list);       /* List of hubs needing servicing */
92
93 /* Wakes up khubd */
94 static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
95
96 static struct task_struct *khubd_task;
97
98 /* cycle leds on hubs that aren't blinking for attention */
99 static int blinkenlights = 0;
100 module_param (blinkenlights, bool, S_IRUGO);
101 MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
102
103 /*
104  * As of 2.6.10 we introduce a new USB device initialization scheme which
105  * closely resembles the way Windows works.  Hopefully it will be compatible
106  * with a wider range of devices than the old scheme.  However some previously
107  * working devices may start giving rise to "device not accepting address"
108  * errors; if that happens the user can try the old scheme by adjusting the
109  * following module parameters.
110  *
111  * For maximum flexibility there are two boolean parameters to control the
112  * hub driver's behavior.  On the first initialization attempt, if the
113  * "old_scheme_first" parameter is set then the old scheme will be used,
114  * otherwise the new scheme is used.  If that fails and "use_both_schemes"
115  * is set, then the driver will make another attempt, using the other scheme.
116  */
117 static int old_scheme_first = 0;
118 module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
119 MODULE_PARM_DESC(old_scheme_first,
120                  "start with the old device initialization scheme");
121
122 static int use_both_schemes = 1;
123 module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
124 MODULE_PARM_DESC(use_both_schemes,
125                 "try the other device initialization scheme if the "
126                 "first one fails");
127
128
129 static inline char *portspeed(int portstatus)
130 {
131         if (portstatus & (1 << USB_PORT_FEAT_HIGHSPEED))
132                 return "480 Mb/s";
133         else if (portstatus & (1 << USB_PORT_FEAT_LOWSPEED))
134                 return "1.5 Mb/s";
135         else
136                 return "12 Mb/s";
137 }
138
139 /* Note that hdev or one of its children must be locked! */
140 static inline struct usb_hub *hdev_to_hub(struct usb_device *hdev)
141 {
142         return usb_get_intfdata(hdev->actconfig->interface[0]);
143 }
144
145 /* USB 2.0 spec Section 11.24.4.5 */
146 static int get_hub_descriptor(struct usb_device *hdev, void *data, int size)
147 {
148         int i, ret;
149
150         for (i = 0; i < 3; i++) {
151                 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
152                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
153                         USB_DT_HUB << 8, 0, data, size,
154                         USB_CTRL_GET_TIMEOUT);
155                 if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
156                         return ret;
157         }
158         return -EINVAL;
159 }
160
161 /*
162  * USB 2.0 spec Section 11.24.2.1
163  */
164 static int clear_hub_feature(struct usb_device *hdev, int feature)
165 {
166         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
167                 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
168 }
169
170 /*
171  * USB 2.0 spec Section 11.24.2.2
172  */
173 static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
174 {
175         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
176                 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
177                 NULL, 0, 1000);
178 }
179
180 /*
181  * USB 2.0 spec Section 11.24.2.13
182  */
183 static int set_port_feature(struct usb_device *hdev, int port1, int feature)
184 {
185         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
186                 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
187                 NULL, 0, 1000);
188 }
189
190 /*
191  * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
192  * for info about using port indicators
193  */
194 static void set_port_led(
195         struct usb_hub *hub,
196         int port1,
197         int selector
198 )
199 {
200         int status = set_port_feature(hub->hdev, (selector << 8) | port1,
201                         USB_PORT_FEAT_INDICATOR);
202         if (status < 0)
203                 dev_dbg (hub->intfdev,
204                         "port %d indicator %s status %d\n",
205                         port1,
206                         ({ char *s; switch (selector) {
207                         case HUB_LED_AMBER: s = "amber"; break;
208                         case HUB_LED_GREEN: s = "green"; break;
209                         case HUB_LED_OFF: s = "off"; break;
210                         case HUB_LED_AUTO: s = "auto"; break;
211                         default: s = "??"; break;
212                         }; s; }),
213                         status);
214 }
215
216 #define LED_CYCLE_PERIOD        ((2*HZ)/3)
217
218 static void led_work (struct work_struct *work)
219 {
220         struct usb_hub          *hub =
221                 container_of(work, struct usb_hub, leds.work);
222         struct usb_device       *hdev = hub->hdev;
223         unsigned                i;
224         unsigned                changed = 0;
225         int                     cursor = -1;
226
227         if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
228                 return;
229
230         for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
231                 unsigned        selector, mode;
232
233                 /* 30%-50% duty cycle */
234
235                 switch (hub->indicator[i]) {
236                 /* cycle marker */
237                 case INDICATOR_CYCLE:
238                         cursor = i;
239                         selector = HUB_LED_AUTO;
240                         mode = INDICATOR_AUTO;
241                         break;
242                 /* blinking green = sw attention */
243                 case INDICATOR_GREEN_BLINK:
244                         selector = HUB_LED_GREEN;
245                         mode = INDICATOR_GREEN_BLINK_OFF;
246                         break;
247                 case INDICATOR_GREEN_BLINK_OFF:
248                         selector = HUB_LED_OFF;
249                         mode = INDICATOR_GREEN_BLINK;
250                         break;
251                 /* blinking amber = hw attention */
252                 case INDICATOR_AMBER_BLINK:
253                         selector = HUB_LED_AMBER;
254                         mode = INDICATOR_AMBER_BLINK_OFF;
255                         break;
256                 case INDICATOR_AMBER_BLINK_OFF:
257                         selector = HUB_LED_OFF;
258                         mode = INDICATOR_AMBER_BLINK;
259                         break;
260                 /* blink green/amber = reserved */
261                 case INDICATOR_ALT_BLINK:
262                         selector = HUB_LED_GREEN;
263                         mode = INDICATOR_ALT_BLINK_OFF;
264                         break;
265                 case INDICATOR_ALT_BLINK_OFF:
266                         selector = HUB_LED_AMBER;
267                         mode = INDICATOR_ALT_BLINK;
268                         break;
269                 default:
270                         continue;
271                 }
272                 if (selector != HUB_LED_AUTO)
273                         changed = 1;
274                 set_port_led(hub, i + 1, selector);
275                 hub->indicator[i] = mode;
276         }
277         if (!changed && blinkenlights) {
278                 cursor++;
279                 cursor %= hub->descriptor->bNbrPorts;
280                 set_port_led(hub, cursor + 1, HUB_LED_GREEN);
281                 hub->indicator[cursor] = INDICATOR_CYCLE;
282                 changed++;
283         }
284         if (changed)
285                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
286 }
287
288 /* use a short timeout for hub/port status fetches */
289 #define USB_STS_TIMEOUT         1000
290 #define USB_STS_RETRIES         5
291
292 /*
293  * USB 2.0 spec Section 11.24.2.6
294  */
295 static int get_hub_status(struct usb_device *hdev,
296                 struct usb_hub_status *data)
297 {
298         int i, status = -ETIMEDOUT;
299
300         for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
301                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
302                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
303                         data, sizeof(*data), USB_STS_TIMEOUT);
304         }
305         return status;
306 }
307
308 /*
309  * USB 2.0 spec Section 11.24.2.7
310  */
311 static int get_port_status(struct usb_device *hdev, int port1,
312                 struct usb_port_status *data)
313 {
314         int i, status = -ETIMEDOUT;
315
316         for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
317                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
318                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
319                         data, sizeof(*data), USB_STS_TIMEOUT);
320         }
321         return status;
322 }
323
324 static void kick_khubd(struct usb_hub *hub)
325 {
326         unsigned long   flags;
327
328         /* Suppress autosuspend until khubd runs */
329         to_usb_interface(hub->intfdev)->pm_usage_cnt = 1;
330
331         spin_lock_irqsave(&hub_event_lock, flags);
332         if (!hub->disconnected & list_empty(&hub->event_list)) {
333                 list_add_tail(&hub->event_list, &hub_event_list);
334                 wake_up(&khubd_wait);
335         }
336         spin_unlock_irqrestore(&hub_event_lock, flags);
337 }
338
339 void usb_kick_khubd(struct usb_device *hdev)
340 {
341         /* FIXME: What if hdev isn't bound to the hub driver? */
342         kick_khubd(hdev_to_hub(hdev));
343 }
344
345
346 /* completion function, fires on port status changes and various faults */
347 static void hub_irq(struct urb *urb)
348 {
349         struct usb_hub *hub = urb->context;
350         int status;
351         int i;
352         unsigned long bits;
353
354         switch (urb->status) {
355         case -ENOENT:           /* synchronous unlink */
356         case -ECONNRESET:       /* async unlink */
357         case -ESHUTDOWN:        /* hardware going away */
358                 return;
359
360         default:                /* presumably an error */
361                 /* Cause a hub reset after 10 consecutive errors */
362                 dev_dbg (hub->intfdev, "transfer --> %d\n", urb->status);
363                 if ((++hub->nerrors < 10) || hub->error)
364                         goto resubmit;
365                 hub->error = urb->status;
366                 /* FALL THROUGH */
367
368         /* let khubd handle things */
369         case 0:                 /* we got data:  port status changed */
370                 bits = 0;
371                 for (i = 0; i < urb->actual_length; ++i)
372                         bits |= ((unsigned long) ((*hub->buffer)[i]))
373                                         << (i*8);
374                 hub->event_bits[0] = bits;
375                 break;
376         }
377
378         hub->nerrors = 0;
379
380         /* Something happened, let khubd figure it out */
381         kick_khubd(hub);
382
383 resubmit:
384         if (hub->quiescing)
385                 return;
386
387         if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
388                         && status != -ENODEV && status != -EPERM)
389                 dev_err (hub->intfdev, "resubmit --> %d\n", status);
390 }
391
392 /* USB 2.0 spec Section 11.24.2.3 */
393 static inline int
394 hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
395 {
396         return usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
397                                HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
398                                tt, NULL, 0, 1000);
399 }
400
401 /*
402  * enumeration blocks khubd for a long time. we use keventd instead, since
403  * long blocking there is the exception, not the rule.  accordingly, HCDs
404  * talking to TTs must queue control transfers (not just bulk and iso), so
405  * both can talk to the same hub concurrently.
406  */
407 static void hub_tt_kevent (struct work_struct *work)
408 {
409         struct usb_hub          *hub =
410                 container_of(work, struct usb_hub, tt.kevent);
411         unsigned long           flags;
412         int                     limit = 100;
413
414         spin_lock_irqsave (&hub->tt.lock, flags);
415         while (--limit && !list_empty (&hub->tt.clear_list)) {
416                 struct list_head        *temp;
417                 struct usb_tt_clear     *clear;
418                 struct usb_device       *hdev = hub->hdev;
419                 int                     status;
420
421                 temp = hub->tt.clear_list.next;
422                 clear = list_entry (temp, struct usb_tt_clear, clear_list);
423                 list_del (&clear->clear_list);
424
425                 /* drop lock so HCD can concurrently report other TT errors */
426                 spin_unlock_irqrestore (&hub->tt.lock, flags);
427                 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
428                 spin_lock_irqsave (&hub->tt.lock, flags);
429
430                 if (status)
431                         dev_err (&hdev->dev,
432                                 "clear tt %d (%04x) error %d\n",
433                                 clear->tt, clear->devinfo, status);
434                 kfree(clear);
435         }
436         spin_unlock_irqrestore (&hub->tt.lock, flags);
437 }
438
439 /**
440  * usb_hub_tt_clear_buffer - clear control/bulk TT state in high speed hub
441  * @udev: the device whose split transaction failed
442  * @pipe: identifies the endpoint of the failed transaction
443  *
444  * High speed HCDs use this to tell the hub driver that some split control or
445  * bulk transaction failed in a way that requires clearing internal state of
446  * a transaction translator.  This is normally detected (and reported) from
447  * interrupt context.
448  *
449  * It may not be possible for that hub to handle additional full (or low)
450  * speed transactions until that state is fully cleared out.
451  */
452 void usb_hub_tt_clear_buffer (struct usb_device *udev, int pipe)
453 {
454         struct usb_tt           *tt = udev->tt;
455         unsigned long           flags;
456         struct usb_tt_clear     *clear;
457
458         /* we've got to cope with an arbitrary number of pending TT clears,
459          * since each TT has "at least two" buffers that can need it (and
460          * there can be many TTs per hub).  even if they're uncommon.
461          */
462         if ((clear = kmalloc (sizeof *clear, GFP_ATOMIC)) == NULL) {
463                 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
464                 /* FIXME recover somehow ... RESET_TT? */
465                 return;
466         }
467
468         /* info that CLEAR_TT_BUFFER needs */
469         clear->tt = tt->multi ? udev->ttport : 1;
470         clear->devinfo = usb_pipeendpoint (pipe);
471         clear->devinfo |= udev->devnum << 4;
472         clear->devinfo |= usb_pipecontrol (pipe)
473                         ? (USB_ENDPOINT_XFER_CONTROL << 11)
474                         : (USB_ENDPOINT_XFER_BULK << 11);
475         if (usb_pipein (pipe))
476                 clear->devinfo |= 1 << 15;
477         
478         /* tell keventd to clear state for this TT */
479         spin_lock_irqsave (&tt->lock, flags);
480         list_add_tail (&clear->clear_list, &tt->clear_list);
481         schedule_work (&tt->kevent);
482         spin_unlock_irqrestore (&tt->lock, flags);
483 }
484
485 static void hub_power_on(struct usb_hub *hub)
486 {
487         int port1;
488         unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
489         u16 wHubCharacteristics =
490                         le16_to_cpu(hub->descriptor->wHubCharacteristics);
491
492         /* Enable power on each port.  Some hubs have reserved values
493          * of LPSM (> 2) in their descriptors, even though they are
494          * USB 2.0 hubs.  Some hubs do not implement port-power switching
495          * but only emulate it.  In all cases, the ports won't work
496          * unless we send these messages to the hub.
497          */
498         if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2)
499                 dev_dbg(hub->intfdev, "enabling power on all ports\n");
500         else
501                 dev_dbg(hub->intfdev, "trying to enable port power on "
502                                 "non-switchable hub\n");
503         for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
504                 set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
505
506         /* Wait at least 100 msec for power to become stable */
507         msleep(max(pgood_delay, (unsigned) 100));
508 }
509
510 static void hub_quiesce(struct usb_hub *hub)
511 {
512         /* (nonblocking) khubd and related activity won't re-trigger */
513         hub->quiescing = 1;
514         hub->activating = 0;
515
516         /* (blocking) stop khubd and related activity */
517         usb_kill_urb(hub->urb);
518         if (hub->has_indicators)
519                 cancel_delayed_work(&hub->leds);
520         if (hub->has_indicators || hub->tt.hub)
521                 flush_scheduled_work();
522 }
523
524 static void hub_activate(struct usb_hub *hub)
525 {
526         int     status;
527
528         hub->quiescing = 0;
529         hub->activating = 1;
530
531         status = usb_submit_urb(hub->urb, GFP_NOIO);
532         if (status < 0)
533                 dev_err(hub->intfdev, "activate --> %d\n", status);
534         if (hub->has_indicators && blinkenlights)
535                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
536
537         /* scan all ports ASAP */
538         kick_khubd(hub);
539 }
540
541 static int hub_hub_status(struct usb_hub *hub,
542                 u16 *status, u16 *change)
543 {
544         int ret;
545
546         mutex_lock(&hub->status_mutex);
547         ret = get_hub_status(hub->hdev, &hub->status->hub);
548         if (ret < 0)
549                 dev_err (hub->intfdev,
550                         "%s failed (err = %d)\n", __FUNCTION__, ret);
551         else {
552                 *status = le16_to_cpu(hub->status->hub.wHubStatus);
553                 *change = le16_to_cpu(hub->status->hub.wHubChange); 
554                 ret = 0;
555         }
556         mutex_unlock(&hub->status_mutex);
557         return ret;
558 }
559
560 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
561 {
562         struct usb_device *hdev = hub->hdev;
563         int ret = 0;
564
565         if (hdev->children[port1-1] && set_state)
566                 usb_set_device_state(hdev->children[port1-1],
567                                 USB_STATE_NOTATTACHED);
568         if (!hub->error)
569                 ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
570         if (ret)
571                 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
572                                 port1, ret);
573         return ret;
574 }
575
576 /*
577  * Disable a port and mark a logical connnect-change event, so that some
578  * time later khubd will disconnect() any existing usb_device on the port
579  * and will re-enumerate if there actually is a device attached.
580  */
581 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
582 {
583         dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
584         hub_port_disable(hub, port1, 1);
585
586         /* FIXME let caller ask to power down the port:
587          *  - some devices won't enumerate without a VBUS power cycle
588          *  - SRP saves power that way
589          *  - ... new call, TBD ...
590          * That's easy if this hub can switch power per-port, and
591          * khubd reactivates the port later (timer, SRP, etc).
592          * Powerdown must be optional, because of reset/DFU.
593          */
594
595         set_bit(port1, hub->change_bits);
596         kick_khubd(hub);
597 }
598
599 static void disconnect_all_children(struct usb_hub *hub, int logical)
600 {
601         struct usb_device *hdev = hub->hdev;
602         int port1;
603
604         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
605                 if (hdev->children[port1-1]) {
606                         if (logical)
607                                 hub_port_logical_disconnect(hub, port1);
608                         else
609                                 usb_disconnect(&hdev->children[port1-1]);
610                 }
611         }
612 }
613
614 /* caller has locked the hub device */
615 static int hub_pre_reset(struct usb_interface *intf)
616 {
617         struct usb_hub *hub = usb_get_intfdata(intf);
618
619         disconnect_all_children(hub, 0);
620         hub_quiesce(hub);
621         return 0;
622 }
623
624 /* caller has locked the hub device */
625 static int hub_post_reset(struct usb_interface *intf)
626 {
627         struct usb_hub *hub = usb_get_intfdata(intf);
628
629         hub_power_on(hub);
630         hub_activate(hub);
631         return 0;
632 }
633
634 static int hub_configure(struct usb_hub *hub,
635         struct usb_endpoint_descriptor *endpoint)
636 {
637         struct usb_device *hdev = hub->hdev;
638         struct device *hub_dev = hub->intfdev;
639         u16 hubstatus, hubchange;
640         u16 wHubCharacteristics;
641         unsigned int pipe;
642         int maxp, ret;
643         char *message;
644
645         hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
646                         &hub->buffer_dma);
647         if (!hub->buffer) {
648                 message = "can't allocate hub irq buffer";
649                 ret = -ENOMEM;
650                 goto fail;
651         }
652
653         hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
654         if (!hub->status) {
655                 message = "can't kmalloc hub status buffer";
656                 ret = -ENOMEM;
657                 goto fail;
658         }
659         mutex_init(&hub->status_mutex);
660
661         hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
662         if (!hub->descriptor) {
663                 message = "can't kmalloc hub descriptor";
664                 ret = -ENOMEM;
665                 goto fail;
666         }
667
668         /* Request the entire hub descriptor.
669          * hub->descriptor can handle USB_MAXCHILDREN ports,
670          * but the hub can/will return fewer bytes here.
671          */
672         ret = get_hub_descriptor(hdev, hub->descriptor,
673                         sizeof(*hub->descriptor));
674         if (ret < 0) {
675                 message = "can't read hub descriptor";
676                 goto fail;
677         } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
678                 message = "hub has too many ports!";
679                 ret = -ENODEV;
680                 goto fail;
681         }
682
683         hdev->maxchild = hub->descriptor->bNbrPorts;
684         dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
685                 (hdev->maxchild == 1) ? "" : "s");
686
687         wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
688
689         if (wHubCharacteristics & HUB_CHAR_COMPOUND) {
690                 int     i;
691                 char    portstr [USB_MAXCHILDREN + 1];
692
693                 for (i = 0; i < hdev->maxchild; i++)
694                         portstr[i] = hub->descriptor->DeviceRemovable
695                                     [((i + 1) / 8)] & (1 << ((i + 1) % 8))
696                                 ? 'F' : 'R';
697                 portstr[hdev->maxchild] = 0;
698                 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
699         } else
700                 dev_dbg(hub_dev, "standalone hub\n");
701
702         switch (wHubCharacteristics & HUB_CHAR_LPSM) {
703                 case 0x00:
704                         dev_dbg(hub_dev, "ganged power switching\n");
705                         break;
706                 case 0x01:
707                         dev_dbg(hub_dev, "individual port power switching\n");
708                         break;
709                 case 0x02:
710                 case 0x03:
711                         dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
712                         break;
713         }
714
715         switch (wHubCharacteristics & HUB_CHAR_OCPM) {
716                 case 0x00:
717                         dev_dbg(hub_dev, "global over-current protection\n");
718                         break;
719                 case 0x08:
720                         dev_dbg(hub_dev, "individual port over-current protection\n");
721                         break;
722                 case 0x10:
723                 case 0x18:
724                         dev_dbg(hub_dev, "no over-current protection\n");
725                         break;
726         }
727
728         spin_lock_init (&hub->tt.lock);
729         INIT_LIST_HEAD (&hub->tt.clear_list);
730         INIT_WORK (&hub->tt.kevent, hub_tt_kevent);
731         switch (hdev->descriptor.bDeviceProtocol) {
732                 case 0:
733                         break;
734                 case 1:
735                         dev_dbg(hub_dev, "Single TT\n");
736                         hub->tt.hub = hdev;
737                         break;
738                 case 2:
739                         ret = usb_set_interface(hdev, 0, 1);
740                         if (ret == 0) {
741                                 dev_dbg(hub_dev, "TT per port\n");
742                                 hub->tt.multi = 1;
743                         } else
744                                 dev_err(hub_dev, "Using single TT (err %d)\n",
745                                         ret);
746                         hub->tt.hub = hdev;
747                         break;
748                 default:
749                         dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
750                                 hdev->descriptor.bDeviceProtocol);
751                         break;
752         }
753
754         /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
755         switch (wHubCharacteristics & HUB_CHAR_TTTT) {
756                 case HUB_TTTT_8_BITS:
757                         if (hdev->descriptor.bDeviceProtocol != 0) {
758                                 hub->tt.think_time = 666;
759                                 dev_dbg(hub_dev, "TT requires at most %d "
760                                                 "FS bit times (%d ns)\n",
761                                         8, hub->tt.think_time);
762                         }
763                         break;
764                 case HUB_TTTT_16_BITS:
765                         hub->tt.think_time = 666 * 2;
766                         dev_dbg(hub_dev, "TT requires at most %d "
767                                         "FS bit times (%d ns)\n",
768                                 16, hub->tt.think_time);
769                         break;
770                 case HUB_TTTT_24_BITS:
771                         hub->tt.think_time = 666 * 3;
772                         dev_dbg(hub_dev, "TT requires at most %d "
773                                         "FS bit times (%d ns)\n",
774                                 24, hub->tt.think_time);
775                         break;
776                 case HUB_TTTT_32_BITS:
777                         hub->tt.think_time = 666 * 4;
778                         dev_dbg(hub_dev, "TT requires at most %d "
779                                         "FS bit times (%d ns)\n",
780                                 32, hub->tt.think_time);
781                         break;
782         }
783
784         /* probe() zeroes hub->indicator[] */
785         if (wHubCharacteristics & HUB_CHAR_PORTIND) {
786                 hub->has_indicators = 1;
787                 dev_dbg(hub_dev, "Port indicators are supported\n");
788         }
789
790         dev_dbg(hub_dev, "power on to power good time: %dms\n",
791                 hub->descriptor->bPwrOn2PwrGood * 2);
792
793         /* power budgeting mostly matters with bus-powered hubs,
794          * and battery-powered root hubs (may provide just 8 mA).
795          */
796         ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
797         if (ret < 2) {
798                 message = "can't get hub status";
799                 goto fail;
800         }
801         le16_to_cpus(&hubstatus);
802         if (hdev == hdev->bus->root_hub) {
803                 if (hdev->bus_mA == 0 || hdev->bus_mA >= 500)
804                         hub->mA_per_port = 500;
805                 else {
806                         hub->mA_per_port = hdev->bus_mA;
807                         hub->limited_power = 1;
808                 }
809         } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
810                 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
811                         hub->descriptor->bHubContrCurrent);
812                 hub->limited_power = 1;
813                 if (hdev->maxchild > 0) {
814                         int remaining = hdev->bus_mA -
815                                         hub->descriptor->bHubContrCurrent;
816
817                         if (remaining < hdev->maxchild * 100)
818                                 dev_warn(hub_dev,
819                                         "insufficient power available "
820                                         "to use all downstream ports\n");
821                         hub->mA_per_port = 100;         /* 7.2.1.1 */
822                 }
823         } else {        /* Self-powered external hub */
824                 /* FIXME: What about battery-powered external hubs that
825                  * provide less current per port? */
826                 hub->mA_per_port = 500;
827         }
828         if (hub->mA_per_port < 500)
829                 dev_dbg(hub_dev, "%umA bus power budget for each child\n",
830                                 hub->mA_per_port);
831
832         ret = hub_hub_status(hub, &hubstatus, &hubchange);
833         if (ret < 0) {
834                 message = "can't get hub status";
835                 goto fail;
836         }
837
838         /* local power status reports aren't always correct */
839         if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
840                 dev_dbg(hub_dev, "local power source is %s\n",
841                         (hubstatus & HUB_STATUS_LOCAL_POWER)
842                         ? "lost (inactive)" : "good");
843
844         if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
845                 dev_dbg(hub_dev, "%sover-current condition exists\n",
846                         (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
847
848         /* set up the interrupt endpoint
849          * We use the EP's maxpacket size instead of (PORTS+1+7)/8
850          * bytes as USB2.0[11.12.3] says because some hubs are known
851          * to send more data (and thus cause overflow). For root hubs,
852          * maxpktsize is defined in hcd.c's fake endpoint descriptors
853          * to be big enough for at least USB_MAXCHILDREN ports. */
854         pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
855         maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
856
857         if (maxp > sizeof(*hub->buffer))
858                 maxp = sizeof(*hub->buffer);
859
860         hub->urb = usb_alloc_urb(0, GFP_KERNEL);
861         if (!hub->urb) {
862                 message = "couldn't allocate interrupt urb";
863                 ret = -ENOMEM;
864                 goto fail;
865         }
866
867         usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
868                 hub, endpoint->bInterval);
869         hub->urb->transfer_dma = hub->buffer_dma;
870         hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
871
872         /* maybe cycle the hub leds */
873         if (hub->has_indicators && blinkenlights)
874                 hub->indicator [0] = INDICATOR_CYCLE;
875
876         hub_power_on(hub);
877         hub_activate(hub);
878         return 0;
879
880 fail:
881         dev_err (hub_dev, "config failed, %s (err %d)\n",
882                         message, ret);
883         /* hub_disconnect() frees urb and descriptor */
884         return ret;
885 }
886
887 static void hub_release(struct kref *kref)
888 {
889         struct usb_hub *hub = container_of(kref, struct usb_hub, kref);
890
891         usb_put_intf(to_usb_interface(hub->intfdev));
892         kfree(hub);
893 }
894
895 static unsigned highspeed_hubs;
896
897 static void hub_disconnect(struct usb_interface *intf)
898 {
899         struct usb_hub *hub = usb_get_intfdata (intf);
900
901         /* Take the hub off the event list and don't let it be added again */
902         spin_lock_irq(&hub_event_lock);
903         list_del_init(&hub->event_list);
904         hub->disconnected = 1;
905         spin_unlock_irq(&hub_event_lock);
906
907         /* Disconnect all children and quiesce the hub */
908         hub->error = 0;
909         hub_pre_reset(intf);
910
911         usb_set_intfdata (intf, NULL);
912
913         if (hub->hdev->speed == USB_SPEED_HIGH)
914                 highspeed_hubs--;
915
916         usb_free_urb(hub->urb);
917         kfree(hub->descriptor);
918         kfree(hub->status);
919         usb_buffer_free(hub->hdev, sizeof(*hub->buffer), hub->buffer,
920                         hub->buffer_dma);
921
922         kref_put(&hub->kref, hub_release);
923 }
924
925 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
926 {
927         struct usb_host_interface *desc;
928         struct usb_endpoint_descriptor *endpoint;
929         struct usb_device *hdev;
930         struct usb_hub *hub;
931
932         desc = intf->cur_altsetting;
933         hdev = interface_to_usbdev(intf);
934
935 #ifdef  CONFIG_USB_OTG_BLACKLIST_HUB
936         if (hdev->parent) {
937                 dev_warn(&intf->dev, "ignoring external hub\n");
938                 return -ENODEV;
939         }
940 #endif
941
942         /* Some hubs have a subclass of 1, which AFAICT according to the */
943         /*  specs is not defined, but it works */
944         if ((desc->desc.bInterfaceSubClass != 0) &&
945             (desc->desc.bInterfaceSubClass != 1)) {
946 descriptor_error:
947                 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
948                 return -EIO;
949         }
950
951         /* Multiple endpoints? What kind of mutant ninja-hub is this? */
952         if (desc->desc.bNumEndpoints != 1)
953                 goto descriptor_error;
954
955         endpoint = &desc->endpoint[0].desc;
956
957         /* If it's not an interrupt in endpoint, we'd better punt! */
958         if (!usb_endpoint_is_int_in(endpoint))
959                 goto descriptor_error;
960
961         /* We found a hub */
962         dev_info (&intf->dev, "USB hub found\n");
963
964         hub = kzalloc(sizeof(*hub), GFP_KERNEL);
965         if (!hub) {
966                 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
967                 return -ENOMEM;
968         }
969
970         kref_init(&hub->kref);
971         INIT_LIST_HEAD(&hub->event_list);
972         hub->intfdev = &intf->dev;
973         hub->hdev = hdev;
974         INIT_DELAYED_WORK(&hub->leds, led_work);
975         usb_get_intf(intf);
976
977         usb_set_intfdata (intf, hub);
978         intf->needs_remote_wakeup = 1;
979
980         if (hdev->speed == USB_SPEED_HIGH)
981                 highspeed_hubs++;
982
983         if (hub_configure(hub, endpoint) >= 0)
984                 return 0;
985
986         hub_disconnect (intf);
987         return -ENODEV;
988 }
989
990 static int
991 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
992 {
993         struct usb_device *hdev = interface_to_usbdev (intf);
994
995         /* assert ifno == 0 (part of hub spec) */
996         switch (code) {
997         case USBDEVFS_HUB_PORTINFO: {
998                 struct usbdevfs_hub_portinfo *info = user_data;
999                 int i;
1000
1001                 spin_lock_irq(&device_state_lock);
1002                 if (hdev->devnum <= 0)
1003                         info->nports = 0;
1004                 else {
1005                         info->nports = hdev->maxchild;
1006                         for (i = 0; i < info->nports; i++) {
1007                                 if (hdev->children[i] == NULL)
1008                                         info->port[i] = 0;
1009                                 else
1010                                         info->port[i] =
1011                                                 hdev->children[i]->devnum;
1012                         }
1013                 }
1014                 spin_unlock_irq(&device_state_lock);
1015
1016                 return info->nports + 1;
1017                 }
1018
1019         default:
1020                 return -ENOSYS;
1021         }
1022 }
1023
1024
1025 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
1026 {
1027         int i;
1028
1029         for (i = 0; i < udev->maxchild; ++i) {
1030                 if (udev->children[i])
1031                         recursively_mark_NOTATTACHED(udev->children[i]);
1032         }
1033         if (udev->state == USB_STATE_SUSPENDED)
1034                 udev->discon_suspended = 1;
1035         udev->state = USB_STATE_NOTATTACHED;
1036 }
1037
1038 /**
1039  * usb_set_device_state - change a device's current state (usbcore, hcds)
1040  * @udev: pointer to device whose state should be changed
1041  * @new_state: new state value to be stored
1042  *
1043  * udev->state is _not_ fully protected by the device lock.  Although
1044  * most transitions are made only while holding the lock, the state can
1045  * can change to USB_STATE_NOTATTACHED at almost any time.  This
1046  * is so that devices can be marked as disconnected as soon as possible,
1047  * without having to wait for any semaphores to be released.  As a result,
1048  * all changes to any device's state must be protected by the
1049  * device_state_lock spinlock.
1050  *
1051  * Once a device has been added to the device tree, all changes to its state
1052  * should be made using this routine.  The state should _not_ be set directly.
1053  *
1054  * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1055  * Otherwise udev->state is set to new_state, and if new_state is
1056  * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1057  * to USB_STATE_NOTATTACHED.
1058  */
1059 void usb_set_device_state(struct usb_device *udev,
1060                 enum usb_device_state new_state)
1061 {
1062         unsigned long flags;
1063
1064         spin_lock_irqsave(&device_state_lock, flags);
1065         if (udev->state == USB_STATE_NOTATTACHED)
1066                 ;       /* do nothing */
1067         else if (new_state != USB_STATE_NOTATTACHED) {
1068
1069                 /* root hub wakeup capabilities are managed out-of-band
1070                  * and may involve silicon errata ... ignore them here.
1071                  */
1072                 if (udev->parent) {
1073                         if (udev->state == USB_STATE_SUSPENDED
1074                                         || new_state == USB_STATE_SUSPENDED)
1075                                 ;       /* No change to wakeup settings */
1076                         else if (new_state == USB_STATE_CONFIGURED)
1077                                 device_init_wakeup(&udev->dev,
1078                                         (udev->actconfig->desc.bmAttributes
1079                                          & USB_CONFIG_ATT_WAKEUP));
1080                         else
1081                                 device_init_wakeup(&udev->dev, 0);
1082                 }
1083                 udev->state = new_state;
1084         } else
1085                 recursively_mark_NOTATTACHED(udev);
1086         spin_unlock_irqrestore(&device_state_lock, flags);
1087 }
1088
1089 static void choose_address(struct usb_device *udev)
1090 {
1091         int             devnum;
1092         struct usb_bus  *bus = udev->bus;
1093
1094         /* If khubd ever becomes multithreaded, this will need a lock */
1095
1096         /* Try to allocate the next devnum beginning at bus->devnum_next. */
1097         devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1098                         bus->devnum_next);
1099         if (devnum >= 128)
1100                 devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
1101
1102         bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1103
1104         if (devnum < 128) {
1105                 set_bit(devnum, bus->devmap.devicemap);
1106                 udev->devnum = devnum;
1107         }
1108 }
1109
1110 static void release_address(struct usb_device *udev)
1111 {
1112         if (udev->devnum > 0) {
1113                 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1114                 udev->devnum = -1;
1115         }
1116 }
1117
1118 #ifdef  CONFIG_USB_SUSPEND
1119
1120 static void usb_stop_pm(struct usb_device *udev)
1121 {
1122         /* Synchronize with the ksuspend thread to prevent any more
1123          * autosuspend requests from being submitted, and decrement
1124          * the parent's count of unsuspended children.
1125          */
1126         usb_pm_lock(udev);
1127         if (udev->parent && !udev->discon_suspended)
1128                 usb_autosuspend_device(udev->parent);
1129         usb_pm_unlock(udev);
1130
1131         /* Stop any autosuspend requests already submitted */
1132         cancel_rearming_delayed_work(&udev->autosuspend);
1133 }
1134
1135 #else
1136
1137 static inline void usb_stop_pm(struct usb_device *udev)
1138 { }
1139
1140 #endif
1141
1142 /**
1143  * usb_disconnect - disconnect a device (usbcore-internal)
1144  * @pdev: pointer to device being disconnected
1145  * Context: !in_interrupt ()
1146  *
1147  * Something got disconnected. Get rid of it and all of its children.
1148  *
1149  * If *pdev is a normal device then the parent hub must already be locked.
1150  * If *pdev is a root hub then this routine will acquire the
1151  * usb_bus_list_lock on behalf of the caller.
1152  *
1153  * Only hub drivers (including virtual root hub drivers for host
1154  * controllers) should ever call this.
1155  *
1156  * This call is synchronous, and may not be used in an interrupt context.
1157  */
1158 void usb_disconnect(struct usb_device **pdev)
1159 {
1160         struct usb_device       *udev = *pdev;
1161         int                     i;
1162
1163         if (!udev) {
1164                 pr_debug ("%s nodev\n", __FUNCTION__);
1165                 return;
1166         }
1167
1168         /* mark the device as inactive, so any further urb submissions for
1169          * this device (and any of its children) will fail immediately.
1170          * this quiesces everyting except pending urbs.
1171          */
1172         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1173         dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1174
1175         usb_lock_device(udev);
1176
1177         /* Free up all the children before we remove this device */
1178         for (i = 0; i < USB_MAXCHILDREN; i++) {
1179                 if (udev->children[i])
1180                         usb_disconnect(&udev->children[i]);
1181         }
1182
1183         /* deallocate hcd/hardware state ... nuking all pending urbs and
1184          * cleaning up all state associated with the current configuration
1185          * so that the hardware is now fully quiesced.
1186          */
1187         dev_dbg (&udev->dev, "unregistering device\n");
1188         usb_disable_device(udev, 0);
1189
1190         usb_unlock_device(udev);
1191
1192         /* Unregister the device.  The device driver is responsible
1193          * for removing the device files from usbfs and sysfs and for
1194          * de-configuring the device.
1195          */
1196         device_del(&udev->dev);
1197
1198         /* Free the device number and delete the parent's children[]
1199          * (or root_hub) pointer.
1200          */
1201         release_address(udev);
1202
1203         /* Avoid races with recursively_mark_NOTATTACHED() */
1204         spin_lock_irq(&device_state_lock);
1205         *pdev = NULL;
1206         spin_unlock_irq(&device_state_lock);
1207
1208         usb_stop_pm(udev);
1209
1210         put_device(&udev->dev);
1211 }
1212
1213 #ifdef DEBUG
1214 static void show_string(struct usb_device *udev, char *id, char *string)
1215 {
1216         if (!string)
1217                 return;
1218         dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1219 }
1220
1221 #else
1222 static inline void show_string(struct usb_device *udev, char *id, char *string)
1223 {}
1224 #endif
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 either
1238  * 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  * It will return if the device is configured properly or not.  Zero if
1244  * the interface was registered with the driver core; else a negative
1245  * errno value.
1246  *
1247  * This call is synchronous, and may not be used in an interrupt context.
1248  *
1249  * Only the hub driver or root-hub registrar should ever call this.
1250  */
1251 int usb_new_device(struct usb_device *udev)
1252 {
1253         int err;
1254
1255         /* Determine quirks */
1256         usb_detect_quirks(udev);
1257
1258         err = usb_get_configuration(udev);
1259         if (err < 0) {
1260                 dev_err(&udev->dev, "can't read configurations, error %d\n",
1261                         err);
1262                 goto fail;
1263         }
1264
1265         /* read the standard strings and cache them if present */
1266         udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
1267         udev->manufacturer = usb_cache_string(udev,
1268                         udev->descriptor.iManufacturer);
1269         udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
1270
1271         /* Tell the world! */
1272         dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
1273                         "SerialNumber=%d\n",
1274                         udev->descriptor.iManufacturer,
1275                         udev->descriptor.iProduct,
1276                         udev->descriptor.iSerialNumber);
1277         show_string(udev, "Product", udev->product);
1278         show_string(udev, "Manufacturer", udev->manufacturer);
1279         show_string(udev, "SerialNumber", udev->serial);
1280
1281 #ifdef  CONFIG_USB_OTG
1282         /*
1283          * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1284          * to wake us after we've powered off VBUS; and HNP, switching roles
1285          * "host" to "peripheral".  The OTG descriptor helps figure this out.
1286          */
1287         if (!udev->bus->is_b_host
1288                         && udev->config
1289                         && udev->parent == udev->bus->root_hub) {
1290                 struct usb_otg_descriptor       *desc = 0;
1291                 struct usb_bus                  *bus = udev->bus;
1292
1293                 /* descriptor may appear anywhere in config */
1294                 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1295                                         le16_to_cpu(udev->config[0].desc.wTotalLength),
1296                                         USB_DT_OTG, (void **) &desc) == 0) {
1297                         if (desc->bmAttributes & USB_OTG_HNP) {
1298                                 unsigned                port1 = udev->portnum;
1299
1300                                 dev_info(&udev->dev,
1301                                         "Dual-Role OTG device on %sHNP port\n",
1302                                         (port1 == bus->otg_port)
1303                                                 ? "" : "non-");
1304
1305                                 /* enable HNP before suspend, it's simpler */
1306                                 if (port1 == bus->otg_port)
1307                                         bus->b_hnp_enable = 1;
1308                                 err = usb_control_msg(udev,
1309                                         usb_sndctrlpipe(udev, 0),
1310                                         USB_REQ_SET_FEATURE, 0,
1311                                         bus->b_hnp_enable
1312                                                 ? USB_DEVICE_B_HNP_ENABLE
1313                                                 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1314                                         0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1315                                 if (err < 0) {
1316                                         /* OTG MESSAGE: report errors here,
1317                                          * customize to match your product.
1318                                          */
1319                                         dev_info(&udev->dev,
1320                                                 "can't set HNP mode; %d\n",
1321                                                 err);
1322                                         bus->b_hnp_enable = 0;
1323                                 }
1324                         }
1325                 }
1326         }
1327
1328         if (!is_targeted(udev)) {
1329
1330                 /* Maybe it can talk to us, though we can't talk to it.
1331                  * (Includes HNP test device.)
1332                  */
1333                 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1334                         err = usb_port_suspend(udev);
1335                         if (err < 0)
1336                                 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1337                 }
1338                 err = -ENOTSUPP;
1339                 goto fail;
1340         }
1341 #endif
1342
1343         /* export the usbdev device-node for libusb */
1344         udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
1345                         (((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
1346
1347         /* Register the device.  The device driver is responsible
1348          * for adding the device files to sysfs and for configuring
1349          * the device.
1350          */
1351         err = device_add(&udev->dev);
1352         if (err) {
1353                 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1354                 goto fail;
1355         }
1356
1357         /* Increment the parent's count of unsuspended children */
1358         if (udev->parent)
1359                 usb_autoresume_device(udev->parent);
1360
1361 exit:
1362         return err;
1363
1364 fail:
1365         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1366         goto exit;
1367 }
1368
1369 static int hub_port_status(struct usb_hub *hub, int port1,
1370                                u16 *status, u16 *change)
1371 {
1372         int ret;
1373
1374         mutex_lock(&hub->status_mutex);
1375         ret = get_port_status(hub->hdev, port1, &hub->status->port);
1376         if (ret < 4) {
1377                 dev_err (hub->intfdev,
1378                         "%s failed (err = %d)\n", __FUNCTION__, ret);
1379                 if (ret >= 0)
1380                         ret = -EIO;
1381         } else {
1382                 *status = le16_to_cpu(hub->status->port.wPortStatus);
1383                 *change = le16_to_cpu(hub->status->port.wPortChange); 
1384                 ret = 0;
1385         }
1386         mutex_unlock(&hub->status_mutex);
1387         return ret;
1388 }
1389
1390
1391 /* Returns 1 if @hub is a WUSB root hub, 0 otherwise */
1392 static unsigned hub_is_wusb(struct usb_hub *hub)
1393 {
1394         struct usb_hcd *hcd;
1395         if (hub->hdev->parent != NULL)  /* not a root hub? */
1396                 return 0;
1397         hcd = container_of(hub->hdev->bus, struct usb_hcd, self);
1398         return hcd->wireless;
1399 }
1400
1401
1402 #define PORT_RESET_TRIES        5
1403 #define SET_ADDRESS_TRIES       2
1404 #define GET_DESCRIPTOR_TRIES    2
1405 #define SET_CONFIG_TRIES        (2 * (use_both_schemes + 1))
1406 #define USE_NEW_SCHEME(i)       ((i) / 2 == old_scheme_first)
1407
1408 #define HUB_ROOT_RESET_TIME     50      /* times are in msec */
1409 #define HUB_SHORT_RESET_TIME    10
1410 #define HUB_LONG_RESET_TIME     200
1411 #define HUB_RESET_TIMEOUT       500
1412
1413 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1414                                 struct usb_device *udev, unsigned int delay)
1415 {
1416         int delay_time, ret;
1417         u16 portstatus;
1418         u16 portchange;
1419
1420         for (delay_time = 0;
1421                         delay_time < HUB_RESET_TIMEOUT;
1422                         delay_time += delay) {
1423                 /* wait to give the device a chance to reset */
1424                 msleep(delay);
1425
1426                 /* read and decode port status */
1427                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1428                 if (ret < 0)
1429                         return ret;
1430
1431                 /* Device went away? */
1432                 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1433                         return -ENOTCONN;
1434
1435                 /* bomb out completely if the connection bounced */
1436                 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1437                         return -ENOTCONN;
1438
1439                 /* if we`ve finished resetting, then break out of the loop */
1440                 if (!(portstatus & USB_PORT_STAT_RESET) &&
1441                     (portstatus & USB_PORT_STAT_ENABLE)) {
1442                         if (hub_is_wusb(hub))
1443                                 udev->speed = USB_SPEED_VARIABLE;
1444                         else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1445                                 udev->speed = USB_SPEED_HIGH;
1446                         else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1447                                 udev->speed = USB_SPEED_LOW;
1448                         else
1449                                 udev->speed = USB_SPEED_FULL;
1450                         return 0;
1451                 }
1452
1453                 /* switch to the long delay after two short delay failures */
1454                 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
1455                         delay = HUB_LONG_RESET_TIME;
1456
1457                 dev_dbg (hub->intfdev,
1458                         "port %d not reset yet, waiting %dms\n",
1459                         port1, delay);
1460         }
1461
1462         return -EBUSY;
1463 }
1464
1465 static int hub_port_reset(struct usb_hub *hub, int port1,
1466                                 struct usb_device *udev, unsigned int delay)
1467 {
1468         int i, status;
1469
1470         /* Reset the port */
1471         for (i = 0; i < PORT_RESET_TRIES; i++) {
1472                 status = set_port_feature(hub->hdev,
1473                                 port1, USB_PORT_FEAT_RESET);
1474                 if (status)
1475                         dev_err(hub->intfdev,
1476                                         "cannot reset port %d (err = %d)\n",
1477                                         port1, status);
1478                 else {
1479                         status = hub_port_wait_reset(hub, port1, udev, delay);
1480                         if (status && status != -ENOTCONN)
1481                                 dev_dbg(hub->intfdev,
1482                                                 "port_wait_reset: err = %d\n",
1483                                                 status);
1484                 }
1485
1486                 /* return on disconnect or reset */
1487                 switch (status) {
1488                 case 0:
1489                         /* TRSTRCY = 10 ms; plus some extra */
1490                         msleep(10 + 40);
1491                         /* FALL THROUGH */
1492                 case -ENOTCONN:
1493                 case -ENODEV:
1494                         clear_port_feature(hub->hdev,
1495                                 port1, USB_PORT_FEAT_C_RESET);
1496                         /* FIXME need disconnect() for NOTATTACHED device */
1497                         usb_set_device_state(udev, status
1498                                         ? USB_STATE_NOTATTACHED
1499                                         : USB_STATE_DEFAULT);
1500                         return status;
1501                 }
1502
1503                 dev_dbg (hub->intfdev,
1504                         "port %d not enabled, trying reset again...\n",
1505                         port1);
1506                 delay = HUB_LONG_RESET_TIME;
1507         }
1508
1509         dev_err (hub->intfdev,
1510                 "Cannot enable port %i.  Maybe the USB cable is bad?\n",
1511                 port1);
1512
1513         return status;
1514 }
1515
1516 #ifdef  CONFIG_PM
1517
1518 #ifdef  CONFIG_USB_SUSPEND
1519
1520 /*
1521  * usb_port_suspend - suspend a usb device's upstream port
1522  * @udev: device that's no longer in active use, not a root hub
1523  * Context: must be able to sleep; device not locked; pm locks held
1524  *
1525  * Suspends a USB device that isn't in active use, conserving power.
1526  * Devices may wake out of a suspend, if anything important happens,
1527  * using the remote wakeup mechanism.  They may also be taken out of
1528  * suspend by the host, using usb_port_resume().  It's also routine
1529  * to disconnect devices while they are suspended.
1530  *
1531  * This only affects the USB hardware for a device; its interfaces
1532  * (and, for hubs, child devices) must already have been suspended.
1533  *
1534  * Selective port suspend reduces power; most suspended devices draw
1535  * less than 500 uA.  It's also used in OTG, along with remote wakeup.
1536  * All devices below the suspended port are also suspended.
1537  *
1538  * Devices leave suspend state when the host wakes them up.  Some devices
1539  * also support "remote wakeup", where the device can activate the USB
1540  * tree above them to deliver data, such as a keypress or packet.  In
1541  * some cases, this wakes the USB host.
1542  *
1543  * Suspending OTG devices may trigger HNP, if that's been enabled
1544  * between a pair of dual-role devices.  That will change roles, such
1545  * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
1546  *
1547  * Devices on USB hub ports have only one "suspend" state, corresponding
1548  * to ACPI D2, "may cause the device to lose some context".
1549  * State transitions include:
1550  *
1551  *   - suspend, resume ... when the VBUS power link stays live
1552  *   - suspend, disconnect ... VBUS lost
1553  *
1554  * Once VBUS drop breaks the circuit, the port it's using has to go through
1555  * normal re-enumeration procedures, starting with enabling VBUS power.
1556  * Other than re-initializing the hub (plug/unplug, except for root hubs),
1557  * Linux (2.6) currently has NO mechanisms to initiate that:  no khubd
1558  * timer, no SRP, no requests through sysfs.
1559  *
1560  * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
1561  * the root hub for their bus goes into global suspend ... so we don't
1562  * (falsely) update the device power state to say it suspended.
1563  *
1564  * Returns 0 on success, else negative errno.
1565  */
1566 int usb_port_suspend(struct usb_device *udev)
1567 {
1568         struct usb_hub  *hub = hdev_to_hub(udev->parent);
1569         int             port1 = udev->portnum;
1570         int             status;
1571
1572         // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
1573
1574         /* enable remote wakeup when appropriate; this lets the device
1575          * wake up the upstream hub (including maybe the root hub).
1576          *
1577          * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
1578          * we don't explicitly enable it here.
1579          */
1580         if (udev->do_remote_wakeup) {
1581                 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1582                                 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
1583                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1584                                 NULL, 0,
1585                                 USB_CTRL_SET_TIMEOUT);
1586                 if (status)
1587                         dev_dbg(&udev->dev, "won't remote wakeup, status %d\n",
1588                                         status);
1589         }
1590
1591         /* see 7.1.7.6 */
1592         status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
1593         if (status) {
1594                 dev_dbg(hub->intfdev, "can't suspend port %d, status %d\n",
1595                                 port1, status);
1596                 /* paranoia:  "should not happen" */
1597                 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1598                                 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
1599                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1600                                 NULL, 0,
1601                                 USB_CTRL_SET_TIMEOUT);
1602         } else {
1603                 /* device has up to 10 msec to fully suspend */
1604                 dev_dbg(&udev->dev, "usb %ssuspend\n",
1605                                 udev->auto_pm ? "auto-" : "");
1606                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1607                 msleep(10);
1608         }
1609         return status;
1610 }
1611
1612 /*
1613  * If the USB "suspend" state is in use (rather than "global suspend"),
1614  * many devices will be individually taken out of suspend state using
1615  * special "resume" signaling.  This routine kicks in shortly after
1616  * hardware resume signaling is finished, either because of selective
1617  * resume (by host) or remote wakeup (by device) ... now see what changed
1618  * in the tree that's rooted at this device.
1619  *
1620  * If @udev->reset_resume is set then the device is reset before the
1621  * status check is done.
1622  */
1623 static int finish_port_resume(struct usb_device *udev)
1624 {
1625         int     status = 0;
1626         u16     devstatus;
1627
1628         /* caller owns the udev device lock */
1629         dev_dbg(&udev->dev, "finish %sresume\n",
1630                         udev->reset_resume ? "reset-" : "");
1631
1632         /* usb ch9 identifies four variants of SUSPENDED, based on what
1633          * state the device resumes to.  Linux currently won't see the
1634          * first two on the host side; they'd be inside hub_port_init()
1635          * during many timeouts, but khubd can't suspend until later.
1636          */
1637         usb_set_device_state(udev, udev->actconfig
1638                         ? USB_STATE_CONFIGURED
1639                         : USB_STATE_ADDRESS);
1640
1641         /* 10.5.4.5 says not to reset a suspended port if the attached
1642          * device is enabled for remote wakeup.  Hence the reset
1643          * operation is carried out here, after the port has been
1644          * resumed.
1645          */
1646         if (udev->reset_resume)
1647                 status = usb_reset_device(udev);
1648
1649         /* 10.5.4.5 says be sure devices in the tree are still there.
1650          * For now let's assume the device didn't go crazy on resume,
1651          * and device drivers will know about any resume quirks.
1652          */
1653         if (status == 0) {
1654                 status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
1655                 if (status >= 0)
1656                         status = (status == 2 ? 0 : -ENODEV);
1657         }
1658
1659         if (status) {
1660                 dev_dbg(&udev->dev, "gone after usb resume? status %d\n",
1661                                 status);
1662         } else if (udev->actconfig) {
1663                 le16_to_cpus(&devstatus);
1664                 if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
1665                         status = usb_control_msg(udev,
1666                                         usb_sndctrlpipe(udev, 0),
1667                                         USB_REQ_CLEAR_FEATURE,
1668                                                 USB_RECIP_DEVICE,
1669                                         USB_DEVICE_REMOTE_WAKEUP, 0,
1670                                         NULL, 0,
1671                                         USB_CTRL_SET_TIMEOUT);
1672                         if (status)
1673                                 dev_dbg(&udev->dev, "disable remote "
1674                                         "wakeup, status %d\n", status);
1675                 }
1676                 status = 0;
1677         }
1678         return status;
1679 }
1680
1681 /*
1682  * usb_port_resume - re-activate a suspended usb device's upstream port
1683  * @udev: device to re-activate, not a root hub
1684  * Context: must be able to sleep; device not locked; pm locks held
1685  *
1686  * This will re-activate the suspended device, increasing power usage
1687  * while letting drivers communicate again with its endpoints.
1688  * USB resume explicitly guarantees that the power session between
1689  * the host and the device is the same as it was when the device
1690  * suspended.
1691  *
1692  * If CONFIG_USB_PERSIST and @udev->reset_resume are both set then this
1693  * routine won't check that the port is still enabled.  Furthermore,
1694  * if @udev->reset_resume is set then finish_port_resume() above will
1695  * reset @udev.  The end result is that a broken power session can be
1696  * recovered and @udev will appear to persist across a loss of VBUS power.
1697  *
1698  * For example, if a host controller doesn't maintain VBUS suspend current
1699  * during a system sleep or is reset when the system wakes up, all the USB
1700  * power sessions below it will be broken.  This is especially troublesome
1701  * for mass-storage devices containing mounted filesystems, since the
1702  * device will appear to have disconnected and all the memory mappings
1703  * to it will be lost.  Using the USB_PERSIST facility, the device can be
1704  * made to appear as if it had not disconnected.
1705  *
1706  * This facility is inherently dangerous.  Although usb_reset_device()
1707  * makes every effort to insure that the same device is present after the
1708  * reset as before, it cannot provide a 100% guarantee.  Furthermore it's
1709  * quite possible for a device to remain unaltered but its media to be
1710  * changed.  If the user replaces a flash memory card while the system is
1711  * asleep, he will have only himself to blame when the filesystem on the
1712  * new card is corrupted and the system crashes.
1713  *
1714  * Returns 0 on success, else negative errno.
1715  */
1716 int usb_port_resume(struct usb_device *udev)
1717 {
1718         struct usb_hub  *hub = hdev_to_hub(udev->parent);
1719         int             port1 = udev->portnum;
1720         int             status;
1721         u16             portchange, portstatus;
1722         unsigned        mask_flags, want_flags;
1723
1724         /* Skip the initial Clear-Suspend step for a remote wakeup */
1725         status = hub_port_status(hub, port1, &portstatus, &portchange);
1726         if (status == 0 && !(portstatus & USB_PORT_STAT_SUSPEND))
1727                 goto SuspendCleared;
1728
1729         // dev_dbg(hub->intfdev, "resume port %d\n", port1);
1730
1731         set_bit(port1, hub->busy_bits);
1732
1733         /* see 7.1.7.7; affects power usage, but not budgeting */
1734         status = clear_port_feature(hub->hdev,
1735                         port1, USB_PORT_FEAT_SUSPEND);
1736         if (status) {
1737                 dev_dbg(hub->intfdev, "can't resume port %d, status %d\n",
1738                                 port1, status);
1739         } else {
1740                 /* drive resume for at least 20 msec */
1741                 dev_dbg(&udev->dev, "usb %sresume\n",
1742                                 udev->auto_pm ? "auto-" : "");
1743                 msleep(25);
1744
1745                 /* Virtual root hubs can trigger on GET_PORT_STATUS to
1746                  * stop resume signaling.  Then finish the resume
1747                  * sequence.
1748                  */
1749                 status = hub_port_status(hub, port1, &portstatus, &portchange);
1750
1751  SuspendCleared:
1752                 if (USB_PERSIST && udev->reset_resume)
1753                         want_flags = USB_PORT_STAT_POWER
1754                                         | USB_PORT_STAT_CONNECTION;
1755                 else
1756                         want_flags = USB_PORT_STAT_POWER
1757                                         | USB_PORT_STAT_CONNECTION
1758                                         | USB_PORT_STAT_ENABLE;
1759                 mask_flags = want_flags | USB_PORT_STAT_SUSPEND;
1760
1761                 if (status < 0 || (portstatus & mask_flags) != want_flags) {
1762                         dev_dbg(hub->intfdev,
1763                                 "port %d status %04x.%04x after resume, %d\n",
1764                                 port1, portchange, portstatus, status);
1765                         if (status >= 0)
1766                                 status = -ENODEV;
1767                 } else {
1768                         if (portchange & USB_PORT_STAT_C_SUSPEND)
1769                                 clear_port_feature(hub->hdev, port1,
1770                                                 USB_PORT_FEAT_C_SUSPEND);
1771                         /* TRSMRCY = 10 msec */
1772                         msleep(10);
1773                 }
1774         }
1775
1776         clear_bit(port1, hub->busy_bits);
1777         if (!hub->hdev->parent && !hub->busy_bits[0])
1778                 usb_enable_root_hub_irq(hub->hdev->bus);
1779
1780         if (status == 0)
1781                 status = finish_port_resume(udev);
1782         if (status < 0) {
1783                 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
1784                 hub_port_logical_disconnect(hub, port1);
1785         }
1786         return status;
1787 }
1788
1789 static int remote_wakeup(struct usb_device *udev)
1790 {
1791         int     status = 0;
1792
1793         usb_lock_device(udev);
1794         if (udev->state == USB_STATE_SUSPENDED) {
1795                 dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
1796                 usb_mark_last_busy(udev);
1797                 status = usb_external_resume_device(udev);
1798         }
1799         usb_unlock_device(udev);
1800         return status;
1801 }
1802
1803 #else   /* CONFIG_USB_SUSPEND */
1804
1805 /* When CONFIG_USB_SUSPEND isn't set, we never suspend or resume any ports. */
1806
1807 int usb_port_suspend(struct usb_device *udev)
1808 {
1809         return 0;
1810 }
1811
1812 int usb_port_resume(struct usb_device *udev)
1813 {
1814         int status = 0;
1815
1816         /* However we may need to do a reset-resume */
1817         if (udev->reset_resume) {
1818                 dev_dbg(&udev->dev, "reset-resume\n");
1819                 status = usb_reset_device(udev);
1820         }
1821         return status;
1822 }
1823
1824 static inline int remote_wakeup(struct usb_device *udev)
1825 {
1826         return 0;
1827 }
1828
1829 #endif
1830
1831 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
1832 {
1833         struct usb_hub          *hub = usb_get_intfdata (intf);
1834         struct usb_device       *hdev = hub->hdev;
1835         unsigned                port1;
1836
1837         /* fail if children aren't already suspended */
1838         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1839                 struct usb_device       *udev;
1840
1841                 udev = hdev->children [port1-1];
1842                 if (udev && msg.event == PM_EVENT_SUSPEND &&
1843 #ifdef  CONFIG_USB_SUSPEND
1844                                 udev->state != USB_STATE_SUSPENDED
1845 #else
1846                                 udev->dev.power.power_state.event
1847                                         == PM_EVENT_ON
1848 #endif
1849                                 ) {
1850                         if (!hdev->auto_pm)
1851                                 dev_dbg(&intf->dev, "port %d nyet suspended\n",
1852                                                 port1);
1853                         return -EBUSY;
1854                 }
1855         }
1856
1857         dev_dbg(&intf->dev, "%s\n", __FUNCTION__);
1858
1859         /* stop khubd and related activity */
1860         hub_quiesce(hub);
1861         return 0;
1862 }
1863
1864 static int hub_resume(struct usb_interface *intf)
1865 {
1866         struct usb_hub          *hub = usb_get_intfdata (intf);
1867
1868         dev_dbg(&intf->dev, "%s\n", __FUNCTION__);
1869
1870         /* tell khubd to look for changes on this hub */
1871         hub_activate(hub);
1872         return 0;
1873 }
1874
1875 #ifdef  CONFIG_USB_PERSIST
1876
1877 /* For "persistent-device" resets we must mark the child devices for reset
1878  * and turn off a possible connect-change status (so khubd won't disconnect
1879  * them later).
1880  */
1881 static void mark_children_for_reset_resume(struct usb_hub *hub)
1882 {
1883         struct usb_device *hdev = hub->hdev;
1884         int port1;
1885
1886         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
1887                 struct usb_device *child = hdev->children[port1-1];
1888
1889                 if (child) {
1890                         child->reset_resume = 1;
1891                         clear_port_feature(hdev, port1,
1892                                         USB_PORT_FEAT_C_CONNECTION);
1893                 }
1894         }
1895 }
1896
1897 #else
1898
1899 static inline void mark_children_for_reset_resume(struct usb_hub *hub)
1900 { }
1901
1902 #endif  /* CONFIG_USB_PERSIST */
1903
1904 static int hub_reset_resume(struct usb_interface *intf)
1905 {
1906         struct usb_hub *hub = usb_get_intfdata(intf);
1907
1908         hub_power_on(hub);
1909         if (USB_PERSIST)
1910                 mark_children_for_reset_resume(hub);
1911         else {
1912                 /* Reset-resume doesn't call pre_reset, so we have to
1913                  * disconnect the children here.  But we may not lock
1914                  * the child devices, so we have to do a "logical"
1915                  * disconnect.
1916                  */
1917                 disconnect_all_children(hub, 1);
1918         }
1919         hub_activate(hub);
1920         return 0;
1921 }
1922
1923 /**
1924  * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
1925  * @rhdev: struct usb_device for the root hub
1926  *
1927  * The USB host controller driver calls this function when its root hub
1928  * is resumed and Vbus power has been interrupted or the controller
1929  * has been reset.  The routine marks @rhdev as having lost power.  When
1930  * the hub driver is resumed it will take notice; if CONFIG_USB_PERSIST
1931  * is enabled then it will carry out power-session recovery, otherwise
1932  * it will disconnect all the child devices.
1933  */
1934 void usb_root_hub_lost_power(struct usb_device *rhdev)
1935 {
1936         dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
1937         rhdev->reset_resume = 1;
1938 }
1939 EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
1940
1941 #else   /* CONFIG_PM */
1942
1943 static inline int remote_wakeup(struct usb_device *udev)
1944 {
1945         return 0;
1946 }
1947
1948 #define hub_suspend             NULL
1949 #define hub_resume              NULL
1950 #define hub_reset_resume        NULL
1951 #endif
1952
1953
1954 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
1955  *
1956  * Between connect detection and reset signaling there must be a delay
1957  * of 100ms at least for debounce and power-settling.  The corresponding
1958  * timer shall restart whenever the downstream port detects a disconnect.
1959  * 
1960  * Apparently there are some bluetooth and irda-dongles and a number of
1961  * low-speed devices for which this debounce period may last over a second.
1962  * Not covered by the spec - but easy to deal with.
1963  *
1964  * This implementation uses a 1500ms total debounce timeout; if the
1965  * connection isn't stable by then it returns -ETIMEDOUT.  It checks
1966  * every 25ms for transient disconnects.  When the port status has been
1967  * unchanged for 100ms it returns the port status.
1968  */
1969
1970 #define HUB_DEBOUNCE_TIMEOUT    1500
1971 #define HUB_DEBOUNCE_STEP         25
1972 #define HUB_DEBOUNCE_STABLE      100
1973
1974 static int hub_port_debounce(struct usb_hub *hub, int port1)
1975 {
1976         int ret;
1977         int total_time, stable_time = 0;
1978         u16 portchange, portstatus;
1979         unsigned connection = 0xffff;
1980
1981         for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
1982                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1983                 if (ret < 0)
1984                         return ret;
1985
1986                 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
1987                      (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
1988                         stable_time += HUB_DEBOUNCE_STEP;
1989                         if (stable_time >= HUB_DEBOUNCE_STABLE)
1990                                 break;
1991                 } else {
1992                         stable_time = 0;
1993                         connection = portstatus & USB_PORT_STAT_CONNECTION;
1994                 }
1995
1996                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
1997                         clear_port_feature(hub->hdev, port1,
1998                                         USB_PORT_FEAT_C_CONNECTION);
1999                 }
2000
2001                 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2002                         break;
2003                 msleep(HUB_DEBOUNCE_STEP);
2004         }
2005
2006         dev_dbg (hub->intfdev,
2007                 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2008                 port1, total_time, stable_time, portstatus);
2009
2010         if (stable_time < HUB_DEBOUNCE_STABLE)
2011                 return -ETIMEDOUT;
2012         return portstatus;
2013 }
2014
2015 static void ep0_reinit(struct usb_device *udev)
2016 {
2017         usb_disable_endpoint(udev, 0 + USB_DIR_IN);
2018         usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
2019         udev->ep_in[0] = udev->ep_out[0] = &udev->ep0;
2020 }
2021
2022 #define usb_sndaddr0pipe()      (PIPE_CONTROL << 30)
2023 #define usb_rcvaddr0pipe()      ((PIPE_CONTROL << 30) | USB_DIR_IN)
2024
2025 static int hub_set_address(struct usb_device *udev)
2026 {
2027         int retval;
2028
2029         if (udev->devnum == 0)
2030                 return -EINVAL;
2031         if (udev->state == USB_STATE_ADDRESS)
2032                 return 0;
2033         if (udev->state != USB_STATE_DEFAULT)
2034                 return -EINVAL;
2035         retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2036                 USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
2037                 NULL, 0, USB_CTRL_SET_TIMEOUT);
2038         if (retval == 0) {
2039                 usb_set_device_state(udev, USB_STATE_ADDRESS);
2040                 ep0_reinit(udev);
2041         }
2042         return retval;
2043 }
2044
2045 /* Reset device, (re)assign address, get device descriptor.
2046  * Device connection must be stable, no more debouncing needed.
2047  * Returns device in USB_STATE_ADDRESS, except on error.
2048  *
2049  * If this is called for an already-existing device (as part of
2050  * usb_reset_device), the caller must own the device lock.  For a
2051  * newly detected device that is not accessible through any global
2052  * pointers, it's not necessary to lock the device.
2053  */
2054 static int
2055 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2056                 int retry_counter)
2057 {
2058         static DEFINE_MUTEX(usb_address0_mutex);
2059
2060         struct usb_device       *hdev = hub->hdev;
2061         int                     i, j, retval;
2062         unsigned                delay = HUB_SHORT_RESET_TIME;
2063         enum usb_device_speed   oldspeed = udev->speed;
2064         char                    *speed, *type;
2065
2066         /* root hub ports have a slightly longer reset period
2067          * (from USB 2.0 spec, section 7.1.7.5)
2068          */
2069         if (!hdev->parent) {
2070                 delay = HUB_ROOT_RESET_TIME;
2071                 if (port1 == hdev->bus->otg_port)
2072                         hdev->bus->b_hnp_enable = 0;
2073         }
2074
2075         /* Some low speed devices have problems with the quick delay, so */
2076         /*  be a bit pessimistic with those devices. RHbug #23670 */
2077         if (oldspeed == USB_SPEED_LOW)
2078                 delay = HUB_LONG_RESET_TIME;
2079
2080         mutex_lock(&usb_address0_mutex);
2081
2082         /* Reset the device; full speed may morph to high speed */
2083         retval = hub_port_reset(hub, port1, udev, delay);
2084         if (retval < 0)         /* error or disconnect */
2085                 goto fail;
2086                                 /* success, speed is known */
2087         retval = -ENODEV;
2088
2089         if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2090                 dev_dbg(&udev->dev, "device reset changed speed!\n");
2091                 goto fail;
2092         }
2093         oldspeed = udev->speed;
2094   
2095         /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2096          * it's fixed size except for full speed devices.
2097          * For Wireless USB devices, ep0 max packet is always 512 (tho
2098          * reported as 0xff in the device descriptor). WUSB1.0[4.8.1].
2099          */
2100         switch (udev->speed) {
2101         case USB_SPEED_VARIABLE:        /* fixed at 512 */
2102                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(512);
2103                 break;
2104         case USB_SPEED_HIGH:            /* fixed at 64 */
2105                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2106                 break;
2107         case USB_SPEED_FULL:            /* 8, 16, 32, or 64 */
2108                 /* to determine the ep0 maxpacket size, try to read
2109                  * the device descriptor to get bMaxPacketSize0 and
2110                  * then correct our initial guess.
2111                  */
2112                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2113                 break;
2114         case USB_SPEED_LOW:             /* fixed at 8 */
2115                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
2116                 break;
2117         default:
2118                 goto fail;
2119         }
2120  
2121         type = "";
2122         switch (udev->speed) {
2123         case USB_SPEED_LOW:     speed = "low";  break;
2124         case USB_SPEED_FULL:    speed = "full"; break;
2125         case USB_SPEED_HIGH:    speed = "high"; break;
2126         case USB_SPEED_VARIABLE:
2127                                 speed = "variable";
2128                                 type = "Wireless ";
2129                                 break;
2130         default:                speed = "?";    break;
2131         }
2132         dev_info (&udev->dev,
2133                   "%s %s speed %sUSB device using %s and address %d\n",
2134                   (udev->config) ? "reset" : "new", speed, type,
2135                   udev->bus->controller->driver->name, udev->devnum);
2136
2137         /* Set up TT records, if needed  */
2138         if (hdev->tt) {
2139                 udev->tt = hdev->tt;
2140                 udev->ttport = hdev->ttport;
2141         } else if (udev->speed != USB_SPEED_HIGH
2142                         && hdev->speed == USB_SPEED_HIGH) {
2143                 udev->tt = &hub->tt;
2144                 udev->ttport = port1;
2145         }
2146  
2147         /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2148          * Because device hardware and firmware is sometimes buggy in
2149          * this area, and this is how Linux has done it for ages.
2150          * Change it cautiously.
2151          *
2152          * NOTE:  If USE_NEW_SCHEME() is true we will start by issuing
2153          * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
2154          * so it may help with some non-standards-compliant devices.
2155          * Otherwise we start with SET_ADDRESS and then try to read the
2156          * first 8 bytes of the device descriptor to get the ep0 maxpacket
2157          * value.
2158          */
2159         for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2160                 if (USE_NEW_SCHEME(retry_counter)) {
2161                         struct usb_device_descriptor *buf;
2162                         int r = 0;
2163
2164 #define GET_DESCRIPTOR_BUFSIZE  64
2165                         buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2166                         if (!buf) {
2167                                 retval = -ENOMEM;
2168                                 continue;
2169                         }
2170
2171                         /* Retry on all errors; some devices are flakey.
2172                          * 255 is for WUSB devices, we actually need to use
2173                          * 512 (WUSB1.0[4.8.1]).
2174                          */
2175                         for (j = 0; j < 3; ++j) {
2176                                 buf->bMaxPacketSize0 = 0;
2177                                 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2178                                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2179                                         USB_DT_DEVICE << 8, 0,
2180                                         buf, GET_DESCRIPTOR_BUFSIZE,
2181                                         USB_CTRL_GET_TIMEOUT);
2182                                 switch (buf->bMaxPacketSize0) {
2183                                 case 8: case 16: case 32: case 64: case 255:
2184                                         if (buf->bDescriptorType ==
2185                                                         USB_DT_DEVICE) {
2186                                                 r = 0;
2187                                                 break;
2188                                         }
2189                                         /* FALL THROUGH */
2190                                 default:
2191                                         if (r == 0)
2192                                                 r = -EPROTO;
2193                                         break;
2194                                 }
2195                                 if (r == 0)
2196                                         break;
2197                         }
2198                         udev->descriptor.bMaxPacketSize0 =
2199                                         buf->bMaxPacketSize0;
2200                         kfree(buf);
2201
2202                         retval = hub_port_reset(hub, port1, udev, delay);
2203                         if (retval < 0)         /* error or disconnect */
2204                                 goto fail;
2205                         if (oldspeed != udev->speed) {
2206                                 dev_dbg(&udev->dev,
2207                                         "device reset changed speed!\n");
2208                                 retval = -ENODEV;
2209                                 goto fail;
2210                         }
2211                         if (r) {
2212                                 dev_err(&udev->dev, "device descriptor "
2213                                                 "read/%s, error %d\n",
2214                                                 "64", r);
2215                                 retval = -EMSGSIZE;
2216                                 continue;
2217                         }
2218 #undef GET_DESCRIPTOR_BUFSIZE
2219                 }
2220
2221                 for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2222                         retval = hub_set_address(udev);
2223                         if (retval >= 0)
2224                                 break;
2225                         msleep(200);
2226                 }
2227                 if (retval < 0) {
2228                         dev_err(&udev->dev,
2229                                 "device not accepting address %d, error %d\n",
2230                                 udev->devnum, retval);
2231                         goto fail;
2232                 }
2233  
2234                 /* cope with hardware quirkiness:
2235                  *  - let SET_ADDRESS settle, some device hardware wants it
2236                  *  - read ep0 maxpacket even for high and low speed,
2237                  */
2238                 msleep(10);
2239                 if (USE_NEW_SCHEME(retry_counter))
2240                         break;
2241
2242                 retval = usb_get_device_descriptor(udev, 8);
2243                 if (retval < 8) {
2244                         dev_err(&udev->dev, "device descriptor "
2245                                         "read/%s, error %d\n",
2246                                         "8", retval);
2247                         if (retval >= 0)
2248                                 retval = -EMSGSIZE;
2249                 } else {
2250                         retval = 0;
2251                         break;
2252                 }
2253         }
2254         if (retval)
2255                 goto fail;
2256
2257         i = udev->descriptor.bMaxPacketSize0 == 0xff?
2258             512 : udev->descriptor.bMaxPacketSize0;
2259         if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2260                 if (udev->speed != USB_SPEED_FULL ||
2261                                 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2262                         dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
2263                         retval = -EMSGSIZE;
2264                         goto fail;
2265                 }
2266                 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2267                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2268                 ep0_reinit(udev);
2269         }
2270   
2271         retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2272         if (retval < (signed)sizeof(udev->descriptor)) {
2273                 dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
2274                         "all", retval);
2275                 if (retval >= 0)
2276                         retval = -ENOMSG;
2277                 goto fail;
2278         }
2279
2280         retval = 0;
2281
2282 fail:
2283         if (retval)
2284                 hub_port_disable(hub, port1, 0);
2285         mutex_unlock(&usb_address0_mutex);
2286         return retval;
2287 }
2288
2289 static void
2290 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2291 {
2292         struct usb_qualifier_descriptor *qual;
2293         int                             status;
2294
2295         qual = kmalloc (sizeof *qual, GFP_KERNEL);
2296         if (qual == NULL)
2297                 return;
2298
2299         status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2300                         qual, sizeof *qual);
2301         if (status == sizeof *qual) {
2302                 dev_info(&udev->dev, "not running at top speed; "
2303                         "connect to a high speed hub\n");
2304                 /* hub LEDs are probably harder to miss than syslog */
2305                 if (hub->has_indicators) {
2306                         hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2307                         schedule_delayed_work (&hub->leds, 0);
2308                 }
2309         }
2310         kfree(qual);
2311 }
2312
2313 static unsigned
2314 hub_power_remaining (struct usb_hub *hub)
2315 {
2316         struct usb_device *hdev = hub->hdev;
2317         int remaining;
2318         int port1;
2319
2320         if (!hub->limited_power)
2321                 return 0;
2322
2323         remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
2324         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
2325                 struct usb_device       *udev = hdev->children[port1 - 1];
2326                 int                     delta;
2327
2328                 if (!udev)
2329                         continue;
2330
2331                 /* Unconfigured devices may not use more than 100mA,
2332                  * or 8mA for OTG ports */
2333                 if (udev->actconfig)
2334                         delta = udev->actconfig->desc.bMaxPower * 2;
2335                 else if (port1 != udev->bus->otg_port || hdev->parent)
2336                         delta = 100;
2337                 else
2338                         delta = 8;
2339                 if (delta > hub->mA_per_port)
2340                         dev_warn(&udev->dev, "%dmA is over %umA budget "
2341                                         "for port %d!\n",
2342                                         delta, hub->mA_per_port, port1);
2343                 remaining -= delta;
2344         }
2345         if (remaining < 0) {
2346                 dev_warn(hub->intfdev, "%dmA over power budget!\n",
2347                         - remaining);
2348                 remaining = 0;
2349         }
2350         return remaining;
2351 }
2352
2353 /* Handle physical or logical connection change events.
2354  * This routine is called when:
2355  *      a port connection-change occurs;
2356  *      a port enable-change occurs (often caused by EMI);
2357  *      usb_reset_device() encounters changed descriptors (as from
2358  *              a firmware download)
2359  * caller already locked the hub
2360  */
2361 static void hub_port_connect_change(struct usb_hub *hub, int port1,
2362                                         u16 portstatus, u16 portchange)
2363 {
2364         struct usb_device *hdev = hub->hdev;
2365         struct device *hub_dev = hub->intfdev;
2366         u16 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
2367         int status, i;
2368  
2369         dev_dbg (hub_dev,
2370                 "port %d, status %04x, change %04x, %s\n",
2371                 port1, portstatus, portchange, portspeed (portstatus));
2372
2373         if (hub->has_indicators) {
2374                 set_port_led(hub, port1, HUB_LED_AUTO);
2375                 hub->indicator[port1-1] = INDICATOR_AUTO;
2376         }
2377  
2378         /* Disconnect any existing devices under this port */
2379         if (hdev->children[port1-1])
2380                 usb_disconnect(&hdev->children[port1-1]);
2381         clear_bit(port1, hub->change_bits);
2382
2383 #ifdef  CONFIG_USB_OTG
2384         /* during HNP, don't repeat the debounce */
2385         if (hdev->bus->is_b_host)
2386                 portchange &= ~USB_PORT_STAT_C_CONNECTION;
2387 #endif
2388
2389         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2390                 status = hub_port_debounce(hub, port1);
2391                 if (status < 0) {
2392                         if (printk_ratelimit())
2393                                 dev_err (hub_dev, "connect-debounce failed, "
2394                                                 "port %d disabled\n", port1);
2395                         goto done;
2396                 }
2397                 portstatus = status;
2398         }
2399
2400         /* Return now if nothing is connected */
2401         if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2402
2403                 /* maybe switch power back on (e.g. root hub was reset) */
2404                 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2
2405                                 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
2406                         set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
2407  
2408                 if (portstatus & USB_PORT_STAT_ENABLE)
2409                         goto done;
2410                 return;
2411         }
2412
2413         for (i = 0; i < SET_CONFIG_TRIES; i++) {
2414                 struct usb_device *udev;
2415
2416                 /* reallocate for each attempt, since references
2417                  * to the previous one can escape in various ways
2418                  */
2419                 udev = usb_alloc_dev(hdev, hdev->bus, port1);
2420                 if (!udev) {
2421                         dev_err (hub_dev,
2422                                 "couldn't allocate port %d usb_device\n",
2423                                 port1);
2424                         goto done;
2425                 }
2426
2427                 usb_set_device_state(udev, USB_STATE_POWERED);
2428                 udev->speed = USB_SPEED_UNKNOWN;
2429                 udev->bus_mA = hub->mA_per_port;
2430                 udev->level = hdev->level + 1;
2431
2432                 /* set the address */
2433                 choose_address(udev);
2434                 if (udev->devnum <= 0) {
2435                         status = -ENOTCONN;     /* Don't retry */
2436                         goto loop;
2437                 }
2438
2439                 /* reset and get descriptor */
2440                 status = hub_port_init(hub, udev, port1, i);
2441                 if (status < 0)
2442                         goto loop;
2443
2444                 /* consecutive bus-powered hubs aren't reliable; they can
2445                  * violate the voltage drop budget.  if the new child has
2446                  * a "powered" LED, users should notice we didn't enable it
2447                  * (without reading syslog), even without per-port LEDs
2448                  * on the parent.
2449                  */
2450                 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
2451                                 && udev->bus_mA <= 100) {
2452                         u16     devstat;
2453
2454                         status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
2455                                         &devstat);
2456                         if (status < 2) {
2457                                 dev_dbg(&udev->dev, "get status %d ?\n", status);
2458                                 goto loop_disable;
2459                         }
2460                         le16_to_cpus(&devstat);
2461                         if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
2462                                 dev_err(&udev->dev,
2463                                         "can't connect bus-powered hub "
2464                                         "to this port\n");
2465                                 if (hub->has_indicators) {
2466                                         hub->indicator[port1-1] =
2467                                                 INDICATOR_AMBER_BLINK;
2468                                         schedule_delayed_work (&hub->leds, 0);
2469                                 }
2470                                 status = -ENOTCONN;     /* Don't retry */
2471                                 goto loop_disable;
2472                         }
2473                 }
2474  
2475                 /* check for devices running slower than they could */
2476                 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
2477                                 && udev->speed == USB_SPEED_FULL
2478                                 && highspeed_hubs != 0)
2479                         check_highspeed (hub, udev, port1);
2480
2481                 /* Store the parent's children[] pointer.  At this point
2482                  * udev becomes globally accessible, although presumably
2483                  * no one will look at it until hdev is unlocked.
2484                  */
2485                 status = 0;
2486
2487                 /* We mustn't add new devices if the parent hub has
2488                  * been disconnected; we would race with the
2489                  * recursively_mark_NOTATTACHED() routine.
2490                  */
2491                 spin_lock_irq(&device_state_lock);
2492                 if (hdev->state == USB_STATE_NOTATTACHED)
2493                         status = -ENOTCONN;
2494                 else
2495                         hdev->children[port1-1] = udev;
2496                 spin_unlock_irq(&device_state_lock);
2497
2498                 /* Run it through the hoops (find a driver, etc) */
2499                 if (!status) {
2500                         status = usb_new_device(udev);
2501                         if (status) {
2502                                 spin_lock_irq(&device_state_lock);
2503                                 hdev->children[port1-1] = NULL;
2504                                 spin_unlock_irq(&device_state_lock);
2505                         }
2506                 }
2507
2508                 if (status)
2509                         goto loop_disable;
2510
2511                 status = hub_power_remaining(hub);
2512                 if (status)
2513                         dev_dbg(hub_dev, "%dmA power budget left\n", status);
2514
2515                 return;
2516
2517 loop_disable:
2518                 hub_port_disable(hub, port1, 1);
2519 loop:
2520                 ep0_reinit(udev);
2521                 release_address(udev);
2522                 usb_put_dev(udev);
2523                 if ((status == -ENOTCONN) || (status == -ENOTSUPP))
2524                         break;
2525         }
2526  
2527 done:
2528         hub_port_disable(hub, port1, 1);
2529 }
2530
2531 static void hub_events(void)
2532 {
2533         struct list_head *tmp;
2534         struct usb_device *hdev;
2535         struct usb_interface *intf;
2536         struct usb_hub *hub;
2537         struct device *hub_dev;
2538         u16 hubstatus;
2539         u16 hubchange;
2540         u16 portstatus;
2541         u16 portchange;
2542         int i, ret;
2543         int connect_change;
2544
2545         /*
2546          *  We restart the list every time to avoid a deadlock with
2547          * deleting hubs downstream from this one. This should be
2548          * safe since we delete the hub from the event list.
2549          * Not the most efficient, but avoids deadlocks.
2550          */
2551         while (1) {
2552
2553                 /* Grab the first entry at the beginning of the list */
2554                 spin_lock_irq(&hub_event_lock);
2555                 if (list_empty(&hub_event_list)) {
2556                         spin_unlock_irq(&hub_event_lock);
2557                         break;
2558                 }
2559
2560                 tmp = hub_event_list.next;
2561                 list_del_init(tmp);
2562
2563                 hub = list_entry(tmp, struct usb_hub, event_list);
2564                 kref_get(&hub->kref);
2565                 spin_unlock_irq(&hub_event_lock);
2566
2567                 hdev = hub->hdev;
2568                 hub_dev = hub->intfdev;
2569                 intf = to_usb_interface(hub_dev);
2570                 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
2571                                 hdev->state, hub->descriptor
2572                                         ? hub->descriptor->bNbrPorts
2573                                         : 0,
2574                                 /* NOTE: expects max 15 ports... */
2575                                 (u16) hub->change_bits[0],
2576                                 (u16) hub->event_bits[0]);
2577
2578                 /* Lock the device, then check to see if we were
2579                  * disconnected while waiting for the lock to succeed. */
2580                 usb_lock_device(hdev);
2581                 if (unlikely(hub->disconnected))
2582                         goto loop;
2583
2584                 /* If the hub has died, clean up after it */
2585                 if (hdev->state == USB_STATE_NOTATTACHED) {
2586                         hub->error = -ENODEV;
2587                         hub_pre_reset(intf);
2588                         goto loop;
2589                 }
2590
2591                 /* Autoresume */
2592                 ret = usb_autopm_get_interface(intf);
2593                 if (ret) {
2594                         dev_dbg(hub_dev, "Can't autoresume: %d\n", ret);
2595                         goto loop;
2596                 }
2597
2598                 /* If this is an inactive hub, do nothing */
2599                 if (hub->quiescing)
2600                         goto loop_autopm;
2601
2602                 if (hub->error) {
2603                         dev_dbg (hub_dev, "resetting for error %d\n",
2604                                 hub->error);
2605
2606                         ret = usb_reset_composite_device(hdev, intf);
2607                         if (ret) {
2608                                 dev_dbg (hub_dev,
2609                                         "error resetting hub: %d\n", ret);
2610                                 goto loop_autopm;
2611                         }
2612
2613                         hub->nerrors = 0;
2614                         hub->error = 0;
2615                 }
2616
2617                 /* deal with port status changes */
2618                 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
2619                         if (test_bit(i, hub->busy_bits))
2620                                 continue;
2621                         connect_change = test_bit(i, hub->change_bits);
2622                         if (!test_and_clear_bit(i, hub->event_bits) &&
2623                                         !connect_change && !hub->activating)
2624                                 continue;
2625
2626                         ret = hub_port_status(hub, i,
2627                                         &portstatus, &portchange);
2628                         if (ret < 0)
2629                                 continue;
2630
2631                         if (hub->activating && !hdev->children[i-1] &&
2632                                         (portstatus &
2633                                                 USB_PORT_STAT_CONNECTION))
2634                                 connect_change = 1;
2635
2636                         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2637                                 clear_port_feature(hdev, i,
2638                                         USB_PORT_FEAT_C_CONNECTION);
2639                                 connect_change = 1;
2640                         }
2641
2642                         if (portchange & USB_PORT_STAT_C_ENABLE) {
2643                                 if (!connect_change)
2644                                         dev_dbg (hub_dev,
2645                                                 "port %d enable change, "
2646                                                 "status %08x\n",
2647                                                 i, portstatus);
2648                                 clear_port_feature(hdev, i,
2649                                         USB_PORT_FEAT_C_ENABLE);
2650
2651                                 /*
2652                                  * EM interference sometimes causes badly
2653                                  * shielded USB devices to be shutdown by
2654                                  * the hub, this hack enables them again.
2655                                  * Works at least with mouse driver. 
2656                                  */
2657                                 if (!(portstatus & USB_PORT_STAT_ENABLE)
2658                                     && !connect_change
2659                                     && hdev->children[i-1]) {
2660                                         dev_err (hub_dev,
2661                                             "port %i "
2662                                             "disabled by hub (EMI?), "
2663                                             "re-enabling...\n",
2664                                                 i);
2665                                         connect_change = 1;
2666                                 }
2667                         }
2668
2669                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
2670                                 clear_port_feature(hdev, i,
2671                                         USB_PORT_FEAT_C_SUSPEND);
2672                                 if (hdev->children[i-1]) {
2673                                         ret = remote_wakeup(hdev->
2674                                                         children[i-1]);
2675                                         if (ret < 0)
2676                                                 connect_change = 1;
2677                                 } else {
2678                                         ret = -ENODEV;
2679                                         hub_port_disable(hub, i, 1);
2680                                 }
2681                                 dev_dbg (hub_dev,
2682                                         "resume on port %d, status %d\n",
2683                                         i, ret);
2684                         }
2685                         
2686                         if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
2687                                 dev_err (hub_dev,
2688                                         "over-current change on port %d\n",
2689                                         i);
2690                                 clear_port_feature(hdev, i,
2691                                         USB_PORT_FEAT_C_OVER_CURRENT);
2692                                 hub_power_on(hub);
2693                         }
2694
2695                         if (portchange & USB_PORT_STAT_C_RESET) {
2696                                 dev_dbg (hub_dev,
2697                                         "reset change on port %d\n",
2698                                         i);
2699                                 clear_port_feature(hdev, i,
2700                                         USB_PORT_FEAT_C_RESET);
2701                         }
2702
2703                         if (connect_change)
2704                                 hub_port_connect_change(hub, i,
2705                                                 portstatus, portchange);
2706                 } /* end for i */
2707
2708                 /* deal with hub status changes */
2709                 if (test_and_clear_bit(0, hub->event_bits) == 0)
2710                         ;       /* do nothing */
2711                 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
2712                         dev_err (hub_dev, "get_hub_status failed\n");
2713                 else {
2714                         if (hubchange & HUB_CHANGE_LOCAL_POWER) {
2715                                 dev_dbg (hub_dev, "power change\n");
2716                                 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
2717                                 if (hubstatus & HUB_STATUS_LOCAL_POWER)
2718                                         /* FIXME: Is this always true? */
2719                                         hub->limited_power = 0;
2720                                 else
2721                                         hub->limited_power = 1;
2722                         }
2723                         if (hubchange & HUB_CHANGE_OVERCURRENT) {
2724                                 dev_dbg (hub_dev, "overcurrent change\n");
2725                                 msleep(500);    /* Cool down */
2726                                 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
2727                                 hub_power_on(hub);
2728                         }
2729                 }
2730
2731                 hub->activating = 0;
2732
2733                 /* If this is a root hub, tell the HCD it's okay to
2734                  * re-enable port-change interrupts now. */
2735                 if (!hdev->parent && !hub->busy_bits[0])
2736                         usb_enable_root_hub_irq(hdev->bus);
2737
2738 loop_autopm:
2739                 /* Allow autosuspend if we're not going to run again */
2740                 if (list_empty(&hub->event_list))
2741                         usb_autopm_enable(intf);
2742 loop:
2743                 usb_unlock_device(hdev);
2744                 kref_put(&hub->kref, hub_release);
2745
2746         } /* end while (1) */
2747 }
2748
2749 static int hub_thread(void *__unused)
2750 {
2751         do {
2752                 hub_events();
2753                 wait_event_interruptible(khubd_wait,
2754                                 !list_empty(&hub_event_list) ||
2755                                 kthread_should_stop());
2756                 try_to_freeze();
2757         } while (!kthread_should_stop() || !list_empty(&hub_event_list));
2758
2759         pr_debug("%s: khubd exiting\n", usbcore_name);
2760         return 0;
2761 }
2762
2763 static struct usb_device_id hub_id_table [] = {
2764     { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
2765       .bDeviceClass = USB_CLASS_HUB},
2766     { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
2767       .bInterfaceClass = USB_CLASS_HUB},
2768     { }                                         /* Terminating entry */
2769 };
2770
2771 MODULE_DEVICE_TABLE (usb, hub_id_table);
2772
2773 static struct usb_driver hub_driver = {
2774         .name =         "hub",
2775         .probe =        hub_probe,
2776         .disconnect =   hub_disconnect,
2777         .suspend =      hub_suspend,
2778         .resume =       hub_resume,
2779         .reset_resume = hub_reset_resume,
2780         .pre_reset =    hub_pre_reset,
2781         .post_reset =   hub_post_reset,
2782         .ioctl =        hub_ioctl,
2783         .id_table =     hub_id_table,
2784         .supports_autosuspend = 1,
2785 };
2786
2787 int usb_hub_init(void)
2788 {
2789         if (usb_register(&hub_driver) < 0) {
2790                 printk(KERN_ERR "%s: can't register hub driver\n",
2791                         usbcore_name);
2792                 return -1;
2793         }
2794
2795         khubd_task = kthread_run(hub_thread, NULL, "khubd");
2796         if (!IS_ERR(khubd_task))
2797                 return 0;
2798
2799         /* Fall through if kernel_thread failed */
2800         usb_deregister(&hub_driver);
2801         printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
2802
2803         return -1;
2804 }
2805
2806 void usb_hub_cleanup(void)
2807 {
2808         kthread_stop(khubd_task);
2809
2810         /*
2811          * Hub resources are freed for us by usb_deregister. It calls
2812          * usb_driver_purge on every device which in turn calls that
2813          * devices disconnect function if it is using this driver.
2814          * The hub_disconnect function takes care of releasing the
2815          * individual hub resources. -greg
2816          */
2817         usb_deregister(&hub_driver);
2818 } /* usb_hub_cleanup() */
2819
2820 static int config_descriptors_changed(struct usb_device *udev)
2821 {
2822         unsigned                        index;
2823         unsigned                        len = 0;
2824         struct usb_config_descriptor    *buf;
2825
2826         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2827                 if (len < le16_to_cpu(udev->config[index].desc.wTotalLength))
2828                         len = le16_to_cpu(udev->config[index].desc.wTotalLength);
2829         }
2830         buf = kmalloc (len, GFP_KERNEL);
2831         if (buf == NULL) {
2832                 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
2833                 /* assume the worst */
2834                 return 1;
2835         }
2836         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2837                 int length;
2838                 int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
2839
2840                 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
2841                                 old_length);
2842                 if (length < old_length) {
2843                         dev_dbg(&udev->dev, "config index %d, error %d\n",
2844                                         index, length);
2845                         break;
2846                 }
2847                 if (memcmp (buf, udev->rawdescriptors[index], old_length)
2848                                 != 0) {
2849                         dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
2850                                 index, buf->bConfigurationValue);
2851                         break;
2852                 }
2853         }
2854         kfree(buf);
2855         return index != udev->descriptor.bNumConfigurations;
2856 }
2857
2858 /**
2859  * usb_reset_device - perform a USB port reset to reinitialize a device
2860  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2861  *
2862  * WARNING - don't use this routine to reset a composite device
2863  * (one with multiple interfaces owned by separate drivers)!
2864  * Use usb_reset_composite_device() instead.
2865  *
2866  * Do a port reset, reassign the device's address, and establish its
2867  * former operating configuration.  If the reset fails, or the device's
2868  * descriptors change from their values before the reset, or the original
2869  * configuration and altsettings cannot be restored, a flag will be set
2870  * telling khubd to pretend the device has been disconnected and then
2871  * re-connected.  All drivers will be unbound, and the device will be
2872  * re-enumerated and probed all over again.
2873  *
2874  * Returns 0 if the reset succeeded, -ENODEV if the device has been
2875  * flagged for logical disconnection, or some other negative error code
2876  * if the reset wasn't even attempted.
2877  *
2878  * The caller must own the device lock.  For example, it's safe to use
2879  * this from a driver probe() routine after downloading new firmware.
2880  * For calls that might not occur during probe(), drivers should lock
2881  * the device using usb_lock_device_for_reset().
2882  *
2883  * Locking exception: This routine may also be called from within an
2884  * autoresume handler.  Such usage won't conflict with other tasks
2885  * holding the device lock because these tasks should always call
2886  * usb_autopm_resume_device(), thereby preventing any unwanted autoresume.
2887  */
2888 int usb_reset_device(struct usb_device *udev)
2889 {
2890         struct usb_device               *parent_hdev = udev->parent;
2891         struct usb_hub                  *parent_hub;
2892         struct usb_device_descriptor    descriptor = udev->descriptor;
2893         int                             i, ret = 0;
2894         int                             port1 = udev->portnum;
2895
2896         if (udev->state == USB_STATE_NOTATTACHED ||
2897                         udev->state == USB_STATE_SUSPENDED) {
2898                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
2899                                 udev->state);
2900                 return -EINVAL;
2901         }
2902
2903         if (!parent_hdev) {
2904                 /* this requires hcd-specific logic; see OHCI hc_restart() */
2905                 dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
2906                 return -EISDIR;
2907         }
2908         parent_hub = hdev_to_hub(parent_hdev);
2909
2910         set_bit(port1, parent_hub->busy_bits);
2911         for (i = 0; i < SET_CONFIG_TRIES; ++i) {
2912
2913                 /* ep0 maxpacket size may change; let the HCD know about it.
2914                  * Other endpoints will be handled by re-enumeration. */
2915                 ep0_reinit(udev);
2916                 ret = hub_port_init(parent_hub, udev, port1, i);
2917                 if (ret >= 0 || ret == -ENOTCONN || ret == -ENODEV)
2918                         break;
2919         }
2920         clear_bit(port1, parent_hub->busy_bits);
2921         if (!parent_hdev->parent && !parent_hub->busy_bits[0])
2922                 usb_enable_root_hub_irq(parent_hdev->bus);
2923
2924         if (ret < 0)
2925                 goto re_enumerate;
2926  
2927         /* Device might have changed firmware (DFU or similar) */
2928         if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
2929                         || config_descriptors_changed (udev)) {
2930                 dev_info(&udev->dev, "device firmware changed\n");
2931                 udev->descriptor = descriptor;  /* for disconnect() calls */
2932                 goto re_enumerate;
2933         }
2934   
2935         if (!udev->actconfig)
2936                 goto done;
2937
2938         ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2939                         USB_REQ_SET_CONFIGURATION, 0,
2940                         udev->actconfig->desc.bConfigurationValue, 0,
2941                         NULL, 0, USB_CTRL_SET_TIMEOUT);
2942         if (ret < 0) {
2943                 dev_err(&udev->dev,
2944                         "can't restore configuration #%d (error=%d)\n",
2945                         udev->actconfig->desc.bConfigurationValue, ret);
2946                 goto re_enumerate;
2947         }
2948         usb_set_device_state(udev, USB_STATE_CONFIGURED);
2949
2950         for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
2951                 struct usb_interface *intf = udev->actconfig->interface[i];
2952                 struct usb_interface_descriptor *desc;
2953
2954                 /* set_interface resets host side toggle even
2955                  * for altsetting zero.  the interface may have no driver.
2956                  */
2957                 desc = &intf->cur_altsetting->desc;
2958                 ret = usb_set_interface(udev, desc->bInterfaceNumber,
2959                         desc->bAlternateSetting);
2960                 if (ret < 0) {
2961                         dev_err(&udev->dev, "failed to restore interface %d "
2962                                 "altsetting %d (error=%d)\n",
2963                                 desc->bInterfaceNumber,
2964                                 desc->bAlternateSetting,
2965                                 ret);
2966                         goto re_enumerate;
2967                 }
2968         }
2969
2970 done:
2971         return 0;
2972  
2973 re_enumerate:
2974         hub_port_logical_disconnect(parent_hub, port1);
2975         return -ENODEV;
2976 }
2977 EXPORT_SYMBOL(usb_reset_device);
2978
2979 /**
2980  * usb_reset_composite_device - warn interface drivers and perform a USB port reset
2981  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2982  * @iface: interface bound to the driver making the request (optional)
2983  *
2984  * Warns all drivers bound to registered interfaces (using their pre_reset
2985  * method), performs the port reset, and then lets the drivers know that
2986  * the reset is over (using their post_reset method).
2987  *
2988  * Return value is the same as for usb_reset_device().
2989  *
2990  * The caller must own the device lock.  For example, it's safe to use
2991  * this from a driver probe() routine after downloading new firmware.
2992  * For calls that might not occur during probe(), drivers should lock
2993  * the device using usb_lock_device_for_reset().
2994  *
2995  * The interface locks are acquired during the pre_reset stage and released
2996  * during the post_reset stage.  However if iface is not NULL and is
2997  * currently being probed, we assume that the caller already owns its
2998  * lock.
2999  */
3000 int usb_reset_composite_device(struct usb_device *udev,
3001                 struct usb_interface *iface)
3002 {
3003         int ret;
3004         struct usb_host_config *config = udev->actconfig;
3005
3006         if (udev->state == USB_STATE_NOTATTACHED ||
3007                         udev->state == USB_STATE_SUSPENDED) {
3008                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
3009                                 udev->state);
3010                 return -EINVAL;
3011         }
3012
3013         /* Prevent autosuspend during the reset */
3014         usb_autoresume_device(udev);
3015
3016         if (iface && iface->condition != USB_INTERFACE_BINDING)
3017                 iface = NULL;
3018
3019         if (config) {
3020                 int i;
3021                 struct usb_interface *cintf;
3022                 struct usb_driver *drv;
3023
3024                 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
3025                         cintf = config->interface[i];
3026                         if (cintf != iface)
3027                                 down(&cintf->dev.sem);
3028                         if (device_is_registered(&cintf->dev) &&
3029                                         cintf->dev.driver) {
3030                                 drv = to_usb_driver(cintf->dev.driver);
3031                                 if (drv->pre_reset)
3032                                         (drv->pre_reset)(cintf);
3033         /* FIXME: Unbind if pre_reset returns an error or isn't defined */
3034                         }
3035                 }
3036         }
3037
3038         ret = usb_reset_device(udev);
3039
3040         if (config) {
3041                 int i;
3042                 struct usb_interface *cintf;
3043                 struct usb_driver *drv;
3044
3045                 for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
3046                         cintf = config->interface[i];
3047                         if (device_is_registered(&cintf->dev) &&
3048                                         cintf->dev.driver) {
3049                                 drv = to_usb_driver(cintf->dev.driver);
3050                                 if (drv->post_reset)
3051                                         (drv->post_reset)(cintf);
3052         /* FIXME: Unbind if post_reset returns an error or isn't defined */
3053                         }
3054                         if (cintf != iface)
3055                                 up(&cintf->dev.sem);
3056                 }
3057         }
3058
3059         usb_autosuspend_device(udev);
3060         return ret;
3061 }
3062 EXPORT_SYMBOL(usb_reset_composite_device);