Merge master.kernel.org:/pub/scm/linux/kernel/git/davej/cpufreq
[linux-2.6.git] / drivers / usb / core / hub.c
1 /*
2  * USB hub driver.
3  *
4  * (C) Copyright 1999 Linus Torvalds
5  * (C) Copyright 1999 Johannes Erdfelt
6  * (C) Copyright 1999 Gregory P. Smith
7  * (C) Copyright 2001 Brad Hards (bhards@bigpond.net.au)
8  *
9  */
10
11 #include <linux/kernel.h>
12 #include <linux/errno.h>
13 #include <linux/module.h>
14 #include <linux/moduleparam.h>
15 #include <linux/completion.h>
16 #include <linux/sched.h>
17 #include <linux/list.h>
18 #include <linux/slab.h>
19 #include <linux/ioctl.h>
20 #include <linux/usb.h>
21 #include <linux/usbdevice_fs.h>
22 #include <linux/kthread.h>
23 #include <linux/mutex.h>
24 #include <linux/freezer.h>
25
26 #include <asm/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 /* caller has locked the hub device */
600 static int hub_pre_reset(struct usb_interface *intf)
601 {
602         struct usb_hub *hub = usb_get_intfdata(intf);
603         struct usb_device *hdev = hub->hdev;
604         int i;
605
606         /* Disconnect all the children */
607         for (i = 0; i < hdev->maxchild; ++i) {
608                 if (hdev->children[i])
609                         usb_disconnect(&hdev->children[i]);
610         }
611         hub_quiesce(hub);
612         return 0;
613 }
614
615 /* caller has locked the hub device */
616 static int hub_post_reset(struct usb_interface *intf)
617 {
618         struct usb_hub *hub = usb_get_intfdata(intf);
619
620         hub_power_on(hub);
621         hub_activate(hub);
622         return 0;
623 }
624
625 static int hub_configure(struct usb_hub *hub,
626         struct usb_endpoint_descriptor *endpoint)
627 {
628         struct usb_device *hdev = hub->hdev;
629         struct device *hub_dev = hub->intfdev;
630         u16 hubstatus, hubchange;
631         u16 wHubCharacteristics;
632         unsigned int pipe;
633         int maxp, ret;
634         char *message;
635
636         hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
637                         &hub->buffer_dma);
638         if (!hub->buffer) {
639                 message = "can't allocate hub irq buffer";
640                 ret = -ENOMEM;
641                 goto fail;
642         }
643
644         hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
645         if (!hub->status) {
646                 message = "can't kmalloc hub status buffer";
647                 ret = -ENOMEM;
648                 goto fail;
649         }
650         mutex_init(&hub->status_mutex);
651
652         hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
653         if (!hub->descriptor) {
654                 message = "can't kmalloc hub descriptor";
655                 ret = -ENOMEM;
656                 goto fail;
657         }
658
659         /* Request the entire hub descriptor.
660          * hub->descriptor can handle USB_MAXCHILDREN ports,
661          * but the hub can/will return fewer bytes here.
662          */
663         ret = get_hub_descriptor(hdev, hub->descriptor,
664                         sizeof(*hub->descriptor));
665         if (ret < 0) {
666                 message = "can't read hub descriptor";
667                 goto fail;
668         } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
669                 message = "hub has too many ports!";
670                 ret = -ENODEV;
671                 goto fail;
672         }
673
674         hdev->maxchild = hub->descriptor->bNbrPorts;
675         dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
676                 (hdev->maxchild == 1) ? "" : "s");
677
678         wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
679
680         if (wHubCharacteristics & HUB_CHAR_COMPOUND) {
681                 int     i;
682                 char    portstr [USB_MAXCHILDREN + 1];
683
684                 for (i = 0; i < hdev->maxchild; i++)
685                         portstr[i] = hub->descriptor->DeviceRemovable
686                                     [((i + 1) / 8)] & (1 << ((i + 1) % 8))
687                                 ? 'F' : 'R';
688                 portstr[hdev->maxchild] = 0;
689                 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
690         } else
691                 dev_dbg(hub_dev, "standalone hub\n");
692
693         switch (wHubCharacteristics & HUB_CHAR_LPSM) {
694                 case 0x00:
695                         dev_dbg(hub_dev, "ganged power switching\n");
696                         break;
697                 case 0x01:
698                         dev_dbg(hub_dev, "individual port power switching\n");
699                         break;
700                 case 0x02:
701                 case 0x03:
702                         dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
703                         break;
704         }
705
706         switch (wHubCharacteristics & HUB_CHAR_OCPM) {
707                 case 0x00:
708                         dev_dbg(hub_dev, "global over-current protection\n");
709                         break;
710                 case 0x08:
711                         dev_dbg(hub_dev, "individual port over-current protection\n");
712                         break;
713                 case 0x10:
714                 case 0x18:
715                         dev_dbg(hub_dev, "no over-current protection\n");
716                         break;
717         }
718
719         spin_lock_init (&hub->tt.lock);
720         INIT_LIST_HEAD (&hub->tt.clear_list);
721         INIT_WORK (&hub->tt.kevent, hub_tt_kevent);
722         switch (hdev->descriptor.bDeviceProtocol) {
723                 case 0:
724                         break;
725                 case 1:
726                         dev_dbg(hub_dev, "Single TT\n");
727                         hub->tt.hub = hdev;
728                         break;
729                 case 2:
730                         ret = usb_set_interface(hdev, 0, 1);
731                         if (ret == 0) {
732                                 dev_dbg(hub_dev, "TT per port\n");
733                                 hub->tt.multi = 1;
734                         } else
735                                 dev_err(hub_dev, "Using single TT (err %d)\n",
736                                         ret);
737                         hub->tt.hub = hdev;
738                         break;
739                 default:
740                         dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
741                                 hdev->descriptor.bDeviceProtocol);
742                         break;
743         }
744
745         /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
746         switch (wHubCharacteristics & HUB_CHAR_TTTT) {
747                 case HUB_TTTT_8_BITS:
748                         if (hdev->descriptor.bDeviceProtocol != 0) {
749                                 hub->tt.think_time = 666;
750                                 dev_dbg(hub_dev, "TT requires at most %d "
751                                                 "FS bit times (%d ns)\n",
752                                         8, hub->tt.think_time);
753                         }
754                         break;
755                 case HUB_TTTT_16_BITS:
756                         hub->tt.think_time = 666 * 2;
757                         dev_dbg(hub_dev, "TT requires at most %d "
758                                         "FS bit times (%d ns)\n",
759                                 16, hub->tt.think_time);
760                         break;
761                 case HUB_TTTT_24_BITS:
762                         hub->tt.think_time = 666 * 3;
763                         dev_dbg(hub_dev, "TT requires at most %d "
764                                         "FS bit times (%d ns)\n",
765                                 24, hub->tt.think_time);
766                         break;
767                 case HUB_TTTT_32_BITS:
768                         hub->tt.think_time = 666 * 4;
769                         dev_dbg(hub_dev, "TT requires at most %d "
770                                         "FS bit times (%d ns)\n",
771                                 32, hub->tt.think_time);
772                         break;
773         }
774
775         /* probe() zeroes hub->indicator[] */
776         if (wHubCharacteristics & HUB_CHAR_PORTIND) {
777                 hub->has_indicators = 1;
778                 dev_dbg(hub_dev, "Port indicators are supported\n");
779         }
780
781         dev_dbg(hub_dev, "power on to power good time: %dms\n",
782                 hub->descriptor->bPwrOn2PwrGood * 2);
783
784         /* power budgeting mostly matters with bus-powered hubs,
785          * and battery-powered root hubs (may provide just 8 mA).
786          */
787         ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
788         if (ret < 2) {
789                 message = "can't get hub status";
790                 goto fail;
791         }
792         le16_to_cpus(&hubstatus);
793         if (hdev == hdev->bus->root_hub) {
794                 if (hdev->bus_mA == 0 || hdev->bus_mA >= 500)
795                         hub->mA_per_port = 500;
796                 else {
797                         hub->mA_per_port = hdev->bus_mA;
798                         hub->limited_power = 1;
799                 }
800         } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
801                 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
802                         hub->descriptor->bHubContrCurrent);
803                 hub->limited_power = 1;
804                 if (hdev->maxchild > 0) {
805                         int remaining = hdev->bus_mA -
806                                         hub->descriptor->bHubContrCurrent;
807
808                         if (remaining < hdev->maxchild * 100)
809                                 dev_warn(hub_dev,
810                                         "insufficient power available "
811                                         "to use all downstream ports\n");
812                         hub->mA_per_port = 100;         /* 7.2.1.1 */
813                 }
814         } else {        /* Self-powered external hub */
815                 /* FIXME: What about battery-powered external hubs that
816                  * provide less current per port? */
817                 hub->mA_per_port = 500;
818         }
819         if (hub->mA_per_port < 500)
820                 dev_dbg(hub_dev, "%umA bus power budget for each child\n",
821                                 hub->mA_per_port);
822
823         ret = hub_hub_status(hub, &hubstatus, &hubchange);
824         if (ret < 0) {
825                 message = "can't get hub status";
826                 goto fail;
827         }
828
829         /* local power status reports aren't always correct */
830         if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
831                 dev_dbg(hub_dev, "local power source is %s\n",
832                         (hubstatus & HUB_STATUS_LOCAL_POWER)
833                         ? "lost (inactive)" : "good");
834
835         if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
836                 dev_dbg(hub_dev, "%sover-current condition exists\n",
837                         (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
838
839         /* set up the interrupt endpoint
840          * We use the EP's maxpacket size instead of (PORTS+1+7)/8
841          * bytes as USB2.0[11.12.3] says because some hubs are known
842          * to send more data (and thus cause overflow). For root hubs,
843          * maxpktsize is defined in hcd.c's fake endpoint descriptors
844          * to be big enough for at least USB_MAXCHILDREN ports. */
845         pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
846         maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
847
848         if (maxp > sizeof(*hub->buffer))
849                 maxp = sizeof(*hub->buffer);
850
851         hub->urb = usb_alloc_urb(0, GFP_KERNEL);
852         if (!hub->urb) {
853                 message = "couldn't allocate interrupt urb";
854                 ret = -ENOMEM;
855                 goto fail;
856         }
857
858         usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
859                 hub, endpoint->bInterval);
860         hub->urb->transfer_dma = hub->buffer_dma;
861         hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
862
863         /* maybe cycle the hub leds */
864         if (hub->has_indicators && blinkenlights)
865                 hub->indicator [0] = INDICATOR_CYCLE;
866
867         hub_power_on(hub);
868         hub_activate(hub);
869         return 0;
870
871 fail:
872         dev_err (hub_dev, "config failed, %s (err %d)\n",
873                         message, ret);
874         /* hub_disconnect() frees urb and descriptor */
875         return ret;
876 }
877
878 static void hub_release(struct kref *kref)
879 {
880         struct usb_hub *hub = container_of(kref, struct usb_hub, kref);
881
882         usb_put_intf(to_usb_interface(hub->intfdev));
883         kfree(hub);
884 }
885
886 static unsigned highspeed_hubs;
887
888 static void hub_disconnect(struct usb_interface *intf)
889 {
890         struct usb_hub *hub = usb_get_intfdata (intf);
891
892         /* Take the hub off the event list and don't let it be added again */
893         spin_lock_irq(&hub_event_lock);
894         list_del_init(&hub->event_list);
895         hub->disconnected = 1;
896         spin_unlock_irq(&hub_event_lock);
897
898         /* Disconnect all children and quiesce the hub */
899         hub->error = 0;
900         hub_pre_reset(intf);
901
902         usb_set_intfdata (intf, NULL);
903
904         if (hub->hdev->speed == USB_SPEED_HIGH)
905                 highspeed_hubs--;
906
907         usb_free_urb(hub->urb);
908         kfree(hub->descriptor);
909         kfree(hub->status);
910         usb_buffer_free(hub->hdev, sizeof(*hub->buffer), hub->buffer,
911                         hub->buffer_dma);
912
913         kref_put(&hub->kref, hub_release);
914 }
915
916 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
917 {
918         struct usb_host_interface *desc;
919         struct usb_endpoint_descriptor *endpoint;
920         struct usb_device *hdev;
921         struct usb_hub *hub;
922
923         desc = intf->cur_altsetting;
924         hdev = interface_to_usbdev(intf);
925
926 #ifdef  CONFIG_USB_OTG_BLACKLIST_HUB
927         if (hdev->parent) {
928                 dev_warn(&intf->dev, "ignoring external hub\n");
929                 return -ENODEV;
930         }
931 #endif
932
933         /* Some hubs have a subclass of 1, which AFAICT according to the */
934         /*  specs is not defined, but it works */
935         if ((desc->desc.bInterfaceSubClass != 0) &&
936             (desc->desc.bInterfaceSubClass != 1)) {
937 descriptor_error:
938                 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
939                 return -EIO;
940         }
941
942         /* Multiple endpoints? What kind of mutant ninja-hub is this? */
943         if (desc->desc.bNumEndpoints != 1)
944                 goto descriptor_error;
945
946         endpoint = &desc->endpoint[0].desc;
947
948         /* If it's not an interrupt in endpoint, we'd better punt! */
949         if (!usb_endpoint_is_int_in(endpoint))
950                 goto descriptor_error;
951
952         /* We found a hub */
953         dev_info (&intf->dev, "USB hub found\n");
954
955         hub = kzalloc(sizeof(*hub), GFP_KERNEL);
956         if (!hub) {
957                 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
958                 return -ENOMEM;
959         }
960
961         kref_init(&hub->kref);
962         INIT_LIST_HEAD(&hub->event_list);
963         hub->intfdev = &intf->dev;
964         hub->hdev = hdev;
965         INIT_DELAYED_WORK(&hub->leds, led_work);
966         usb_get_intf(intf);
967
968         usb_set_intfdata (intf, hub);
969         intf->needs_remote_wakeup = 1;
970
971         if (hdev->speed == USB_SPEED_HIGH)
972                 highspeed_hubs++;
973
974         if (hub_configure(hub, endpoint) >= 0)
975                 return 0;
976
977         hub_disconnect (intf);
978         return -ENODEV;
979 }
980
981 static int
982 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
983 {
984         struct usb_device *hdev = interface_to_usbdev (intf);
985
986         /* assert ifno == 0 (part of hub spec) */
987         switch (code) {
988         case USBDEVFS_HUB_PORTINFO: {
989                 struct usbdevfs_hub_portinfo *info = user_data;
990                 int i;
991
992                 spin_lock_irq(&device_state_lock);
993                 if (hdev->devnum <= 0)
994                         info->nports = 0;
995                 else {
996                         info->nports = hdev->maxchild;
997                         for (i = 0; i < info->nports; i++) {
998                                 if (hdev->children[i] == NULL)
999                                         info->port[i] = 0;
1000                                 else
1001                                         info->port[i] =
1002                                                 hdev->children[i]->devnum;
1003                         }
1004                 }
1005                 spin_unlock_irq(&device_state_lock);
1006
1007                 return info->nports + 1;
1008                 }
1009
1010         default:
1011                 return -ENOSYS;
1012         }
1013 }
1014
1015
1016 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
1017 {
1018         int i;
1019
1020         for (i = 0; i < udev->maxchild; ++i) {
1021                 if (udev->children[i])
1022                         recursively_mark_NOTATTACHED(udev->children[i]);
1023         }
1024         if (udev->state == USB_STATE_SUSPENDED)
1025                 udev->discon_suspended = 1;
1026         udev->state = USB_STATE_NOTATTACHED;
1027 }
1028
1029 /**
1030  * usb_set_device_state - change a device's current state (usbcore, hcds)
1031  * @udev: pointer to device whose state should be changed
1032  * @new_state: new state value to be stored
1033  *
1034  * udev->state is _not_ fully protected by the device lock.  Although
1035  * most transitions are made only while holding the lock, the state can
1036  * can change to USB_STATE_NOTATTACHED at almost any time.  This
1037  * is so that devices can be marked as disconnected as soon as possible,
1038  * without having to wait for any semaphores to be released.  As a result,
1039  * all changes to any device's state must be protected by the
1040  * device_state_lock spinlock.
1041  *
1042  * Once a device has been added to the device tree, all changes to its state
1043  * should be made using this routine.  The state should _not_ be set directly.
1044  *
1045  * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1046  * Otherwise udev->state is set to new_state, and if new_state is
1047  * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1048  * to USB_STATE_NOTATTACHED.
1049  */
1050 void usb_set_device_state(struct usb_device *udev,
1051                 enum usb_device_state new_state)
1052 {
1053         unsigned long flags;
1054
1055         spin_lock_irqsave(&device_state_lock, flags);
1056         if (udev->state == USB_STATE_NOTATTACHED)
1057                 ;       /* do nothing */
1058         else if (new_state != USB_STATE_NOTATTACHED) {
1059
1060                 /* root hub wakeup capabilities are managed out-of-band
1061                  * and may involve silicon errata ... ignore them here.
1062                  */
1063                 if (udev->parent) {
1064                         if (udev->state == USB_STATE_SUSPENDED
1065                                         || new_state == USB_STATE_SUSPENDED)
1066                                 ;       /* No change to wakeup settings */
1067                         else if (new_state == USB_STATE_CONFIGURED)
1068                                 device_init_wakeup(&udev->dev,
1069                                         (udev->actconfig->desc.bmAttributes
1070                                          & USB_CONFIG_ATT_WAKEUP));
1071                         else
1072                                 device_init_wakeup(&udev->dev, 0);
1073                 }
1074                 udev->state = new_state;
1075         } else
1076                 recursively_mark_NOTATTACHED(udev);
1077         spin_unlock_irqrestore(&device_state_lock, flags);
1078 }
1079
1080 static void choose_address(struct usb_device *udev)
1081 {
1082         int             devnum;
1083         struct usb_bus  *bus = udev->bus;
1084
1085         /* If khubd ever becomes multithreaded, this will need a lock */
1086
1087         /* Try to allocate the next devnum beginning at bus->devnum_next. */
1088         devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1089                         bus->devnum_next);
1090         if (devnum >= 128)
1091                 devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
1092
1093         bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1094
1095         if (devnum < 128) {
1096                 set_bit(devnum, bus->devmap.devicemap);
1097                 udev->devnum = devnum;
1098         }
1099 }
1100
1101 static void release_address(struct usb_device *udev)
1102 {
1103         if (udev->devnum > 0) {
1104                 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1105                 udev->devnum = -1;
1106         }
1107 }
1108
1109 #ifdef  CONFIG_USB_SUSPEND
1110
1111 static void usb_stop_pm(struct usb_device *udev)
1112 {
1113         /* Synchronize with the ksuspend thread to prevent any more
1114          * autosuspend requests from being submitted, and decrement
1115          * the parent's count of unsuspended children.
1116          */
1117         usb_pm_lock(udev);
1118         if (udev->parent && !udev->discon_suspended)
1119                 usb_autosuspend_device(udev->parent);
1120         usb_pm_unlock(udev);
1121
1122         /* Stop any autosuspend requests already submitted */
1123         cancel_rearming_delayed_work(&udev->autosuspend);
1124 }
1125
1126 #else
1127
1128 static inline void usb_stop_pm(struct usb_device *udev)
1129 { }
1130
1131 #endif
1132
1133 /**
1134  * usb_disconnect - disconnect a device (usbcore-internal)
1135  * @pdev: pointer to device being disconnected
1136  * Context: !in_interrupt ()
1137  *
1138  * Something got disconnected. Get rid of it and all of its children.
1139  *
1140  * If *pdev is a normal device then the parent hub must already be locked.
1141  * If *pdev is a root hub then this routine will acquire the
1142  * usb_bus_list_lock on behalf of the caller.
1143  *
1144  * Only hub drivers (including virtual root hub drivers for host
1145  * controllers) should ever call this.
1146  *
1147  * This call is synchronous, and may not be used in an interrupt context.
1148  */
1149 void usb_disconnect(struct usb_device **pdev)
1150 {
1151         struct usb_device       *udev = *pdev;
1152         int                     i;
1153
1154         if (!udev) {
1155                 pr_debug ("%s nodev\n", __FUNCTION__);
1156                 return;
1157         }
1158
1159         /* mark the device as inactive, so any further urb submissions for
1160          * this device (and any of its children) will fail immediately.
1161          * this quiesces everyting except pending urbs.
1162          */
1163         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1164         dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1165
1166         usb_lock_device(udev);
1167
1168         /* Free up all the children before we remove this device */
1169         for (i = 0; i < USB_MAXCHILDREN; i++) {
1170                 if (udev->children[i])
1171                         usb_disconnect(&udev->children[i]);
1172         }
1173
1174         /* deallocate hcd/hardware state ... nuking all pending urbs and
1175          * cleaning up all state associated with the current configuration
1176          * so that the hardware is now fully quiesced.
1177          */
1178         dev_dbg (&udev->dev, "unregistering device\n");
1179         usb_disable_device(udev, 0);
1180
1181         usb_unlock_device(udev);
1182
1183         /* Unregister the device.  The device driver is responsible
1184          * for removing the device files from usbfs and sysfs and for
1185          * de-configuring the device.
1186          */
1187         device_del(&udev->dev);
1188
1189         /* Free the device number and delete the parent's children[]
1190          * (or root_hub) pointer.
1191          */
1192         release_address(udev);
1193
1194         /* Avoid races with recursively_mark_NOTATTACHED() */
1195         spin_lock_irq(&device_state_lock);
1196         *pdev = NULL;
1197         spin_unlock_irq(&device_state_lock);
1198
1199         usb_stop_pm(udev);
1200
1201         put_device(&udev->dev);
1202 }
1203
1204 #ifdef DEBUG
1205 static void show_string(struct usb_device *udev, char *id, char *string)
1206 {
1207         if (!string)
1208                 return;
1209         dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1210 }
1211
1212 #else
1213 static inline void show_string(struct usb_device *udev, char *id, char *string)
1214 {}
1215 #endif
1216
1217
1218 #ifdef  CONFIG_USB_OTG
1219 #include "otg_whitelist.h"
1220 #endif
1221
1222 /**
1223  * usb_new_device - perform initial device setup (usbcore-internal)
1224  * @udev: newly addressed device (in ADDRESS state)
1225  *
1226  * This is called with devices which have been enumerated, but not yet
1227  * configured.  The device descriptor is available, but not descriptors
1228  * for any device configuration.  The caller must have locked either
1229  * the parent hub (if udev is a normal device) or else the
1230  * usb_bus_list_lock (if udev is a root hub).  The parent's pointer to
1231  * udev has already been installed, but udev is not yet visible through
1232  * sysfs or other filesystem code.
1233  *
1234  * It will return if the device is configured properly or not.  Zero if
1235  * the interface was registered with the driver core; else a negative
1236  * errno value.
1237  *
1238  * This call is synchronous, and may not be used in an interrupt context.
1239  *
1240  * Only the hub driver or root-hub registrar should ever call this.
1241  */
1242 int usb_new_device(struct usb_device *udev)
1243 {
1244         int err;
1245
1246         /* Determine quirks */
1247         usb_detect_quirks(udev);
1248
1249         err = usb_get_configuration(udev);
1250         if (err < 0) {
1251                 dev_err(&udev->dev, "can't read configurations, error %d\n",
1252                         err);
1253                 goto fail;
1254         }
1255
1256         /* read the standard strings and cache them if present */
1257         udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
1258         udev->manufacturer = usb_cache_string(udev,
1259                         udev->descriptor.iManufacturer);
1260         udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
1261
1262         /* Tell the world! */
1263         dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
1264                         "SerialNumber=%d\n",
1265                         udev->descriptor.iManufacturer,
1266                         udev->descriptor.iProduct,
1267                         udev->descriptor.iSerialNumber);
1268         show_string(udev, "Product", udev->product);
1269         show_string(udev, "Manufacturer", udev->manufacturer);
1270         show_string(udev, "SerialNumber", udev->serial);
1271
1272 #ifdef  CONFIG_USB_OTG
1273         /*
1274          * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1275          * to wake us after we've powered off VBUS; and HNP, switching roles
1276          * "host" to "peripheral".  The OTG descriptor helps figure this out.
1277          */
1278         if (!udev->bus->is_b_host
1279                         && udev->config
1280                         && udev->parent == udev->bus->root_hub) {
1281                 struct usb_otg_descriptor       *desc = 0;
1282                 struct usb_bus                  *bus = udev->bus;
1283
1284                 /* descriptor may appear anywhere in config */
1285                 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1286                                         le16_to_cpu(udev->config[0].desc.wTotalLength),
1287                                         USB_DT_OTG, (void **) &desc) == 0) {
1288                         if (desc->bmAttributes & USB_OTG_HNP) {
1289                                 unsigned                port1 = udev->portnum;
1290
1291                                 dev_info(&udev->dev,
1292                                         "Dual-Role OTG device on %sHNP port\n",
1293                                         (port1 == bus->otg_port)
1294                                                 ? "" : "non-");
1295
1296                                 /* enable HNP before suspend, it's simpler */
1297                                 if (port1 == bus->otg_port)
1298                                         bus->b_hnp_enable = 1;
1299                                 err = usb_control_msg(udev,
1300                                         usb_sndctrlpipe(udev, 0),
1301                                         USB_REQ_SET_FEATURE, 0,
1302                                         bus->b_hnp_enable
1303                                                 ? USB_DEVICE_B_HNP_ENABLE
1304                                                 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1305                                         0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1306                                 if (err < 0) {
1307                                         /* OTG MESSAGE: report errors here,
1308                                          * customize to match your product.
1309                                          */
1310                                         dev_info(&udev->dev,
1311                                                 "can't set HNP mode; %d\n",
1312                                                 err);
1313                                         bus->b_hnp_enable = 0;
1314                                 }
1315                         }
1316                 }
1317         }
1318
1319         if (!is_targeted(udev)) {
1320
1321                 /* Maybe it can talk to us, though we can't talk to it.
1322                  * (Includes HNP test device.)
1323                  */
1324                 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1325                         err = usb_port_suspend(udev);
1326                         if (err < 0)
1327                                 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1328                 }
1329                 err = -ENOTSUPP;
1330                 goto fail;
1331         }
1332 #endif
1333
1334         /* export the usbdev device-node for libusb */
1335         udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
1336                         (((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
1337
1338         /* Increment the parent's count of unsuspended children */
1339         if (udev->parent)
1340                 usb_autoresume_device(udev->parent);
1341
1342         /* Register the device.  The device driver is responsible
1343          * for adding the device files to sysfs and for configuring
1344          * the device.
1345          */
1346         err = device_add(&udev->dev);
1347         if (err) {
1348                 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1349                 if (udev->parent)
1350                         usb_autosuspend_device(udev->parent);
1351                 goto fail;
1352         }
1353
1354 exit:
1355         return err;
1356
1357 fail:
1358         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1359         goto exit;
1360 }
1361
1362 static int hub_port_status(struct usb_hub *hub, int port1,
1363                                u16 *status, u16 *change)
1364 {
1365         int ret;
1366
1367         mutex_lock(&hub->status_mutex);
1368         ret = get_port_status(hub->hdev, port1, &hub->status->port);
1369         if (ret < 4) {
1370                 dev_err (hub->intfdev,
1371                         "%s failed (err = %d)\n", __FUNCTION__, ret);
1372                 if (ret >= 0)
1373                         ret = -EIO;
1374         } else {
1375                 *status = le16_to_cpu(hub->status->port.wPortStatus);
1376                 *change = le16_to_cpu(hub->status->port.wPortChange); 
1377                 ret = 0;
1378         }
1379         mutex_unlock(&hub->status_mutex);
1380         return ret;
1381 }
1382
1383
1384 /* Returns 1 if @hub is a WUSB root hub, 0 otherwise */
1385 static unsigned hub_is_wusb(struct usb_hub *hub)
1386 {
1387         struct usb_hcd *hcd;
1388         if (hub->hdev->parent != NULL)  /* not a root hub? */
1389                 return 0;
1390         hcd = container_of(hub->hdev->bus, struct usb_hcd, self);
1391         return hcd->wireless;
1392 }
1393
1394
1395 #define PORT_RESET_TRIES        5
1396 #define SET_ADDRESS_TRIES       2
1397 #define GET_DESCRIPTOR_TRIES    2
1398 #define SET_CONFIG_TRIES        (2 * (use_both_schemes + 1))
1399 #define USE_NEW_SCHEME(i)       ((i) / 2 == old_scheme_first)
1400
1401 #define HUB_ROOT_RESET_TIME     50      /* times are in msec */
1402 #define HUB_SHORT_RESET_TIME    10
1403 #define HUB_LONG_RESET_TIME     200
1404 #define HUB_RESET_TIMEOUT       500
1405
1406 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1407                                 struct usb_device *udev, unsigned int delay)
1408 {
1409         int delay_time, ret;
1410         u16 portstatus;
1411         u16 portchange;
1412
1413         for (delay_time = 0;
1414                         delay_time < HUB_RESET_TIMEOUT;
1415                         delay_time += delay) {
1416                 /* wait to give the device a chance to reset */
1417                 msleep(delay);
1418
1419                 /* read and decode port status */
1420                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1421                 if (ret < 0)
1422                         return ret;
1423
1424                 /* Device went away? */
1425                 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1426                         return -ENOTCONN;
1427
1428                 /* bomb out completely if the connection bounced */
1429                 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1430                         return -ENOTCONN;
1431
1432                 /* if we`ve finished resetting, then break out of the loop */
1433                 if (!(portstatus & USB_PORT_STAT_RESET) &&
1434                     (portstatus & USB_PORT_STAT_ENABLE)) {
1435                         if (hub_is_wusb(hub))
1436                                 udev->speed = USB_SPEED_VARIABLE;
1437                         else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1438                                 udev->speed = USB_SPEED_HIGH;
1439                         else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1440                                 udev->speed = USB_SPEED_LOW;
1441                         else
1442                                 udev->speed = USB_SPEED_FULL;
1443                         return 0;
1444                 }
1445
1446                 /* switch to the long delay after two short delay failures */
1447                 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
1448                         delay = HUB_LONG_RESET_TIME;
1449
1450                 dev_dbg (hub->intfdev,
1451                         "port %d not reset yet, waiting %dms\n",
1452                         port1, delay);
1453         }
1454
1455         return -EBUSY;
1456 }
1457
1458 static int hub_port_reset(struct usb_hub *hub, int port1,
1459                                 struct usb_device *udev, unsigned int delay)
1460 {
1461         int i, status;
1462
1463         /* Reset the port */
1464         for (i = 0; i < PORT_RESET_TRIES; i++) {
1465                 status = set_port_feature(hub->hdev,
1466                                 port1, USB_PORT_FEAT_RESET);
1467                 if (status)
1468                         dev_err(hub->intfdev,
1469                                         "cannot reset port %d (err = %d)\n",
1470                                         port1, status);
1471                 else {
1472                         status = hub_port_wait_reset(hub, port1, udev, delay);
1473                         if (status && status != -ENOTCONN)
1474                                 dev_dbg(hub->intfdev,
1475                                                 "port_wait_reset: err = %d\n",
1476                                                 status);
1477                 }
1478
1479                 /* return on disconnect or reset */
1480                 switch (status) {
1481                 case 0:
1482                         /* TRSTRCY = 10 ms; plus some extra */
1483                         msleep(10 + 40);
1484                         /* FALL THROUGH */
1485                 case -ENOTCONN:
1486                 case -ENODEV:
1487                         clear_port_feature(hub->hdev,
1488                                 port1, USB_PORT_FEAT_C_RESET);
1489                         /* FIXME need disconnect() for NOTATTACHED device */
1490                         usb_set_device_state(udev, status
1491                                         ? USB_STATE_NOTATTACHED
1492                                         : USB_STATE_DEFAULT);
1493                         return status;
1494                 }
1495
1496                 dev_dbg (hub->intfdev,
1497                         "port %d not enabled, trying reset again...\n",
1498                         port1);
1499                 delay = HUB_LONG_RESET_TIME;
1500         }
1501
1502         dev_err (hub->intfdev,
1503                 "Cannot enable port %i.  Maybe the USB cable is bad?\n",
1504                 port1);
1505
1506         return status;
1507 }
1508
1509 #ifdef  CONFIG_PM
1510
1511 #ifdef  CONFIG_USB_SUSPEND
1512
1513 /*
1514  * usb_port_suspend - suspend a usb device's upstream port
1515  * @udev: device that's no longer in active use, not a root hub
1516  * Context: must be able to sleep; device not locked; pm locks held
1517  *
1518  * Suspends a USB device that isn't in active use, conserving power.
1519  * Devices may wake out of a suspend, if anything important happens,
1520  * using the remote wakeup mechanism.  They may also be taken out of
1521  * suspend by the host, using usb_port_resume().  It's also routine
1522  * to disconnect devices while they are suspended.
1523  *
1524  * This only affects the USB hardware for a device; its interfaces
1525  * (and, for hubs, child devices) must already have been suspended.
1526  *
1527  * Selective port suspend reduces power; most suspended devices draw
1528  * less than 500 uA.  It's also used in OTG, along with remote wakeup.
1529  * All devices below the suspended port are also suspended.
1530  *
1531  * Devices leave suspend state when the host wakes them up.  Some devices
1532  * also support "remote wakeup", where the device can activate the USB
1533  * tree above them to deliver data, such as a keypress or packet.  In
1534  * some cases, this wakes the USB host.
1535  *
1536  * Suspending OTG devices may trigger HNP, if that's been enabled
1537  * between a pair of dual-role devices.  That will change roles, such
1538  * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
1539  *
1540  * Devices on USB hub ports have only one "suspend" state, corresponding
1541  * to ACPI D2, "may cause the device to lose some context".
1542  * State transitions include:
1543  *
1544  *   - suspend, resume ... when the VBUS power link stays live
1545  *   - suspend, disconnect ... VBUS lost
1546  *
1547  * Once VBUS drop breaks the circuit, the port it's using has to go through
1548  * normal re-enumeration procedures, starting with enabling VBUS power.
1549  * Other than re-initializing the hub (plug/unplug, except for root hubs),
1550  * Linux (2.6) currently has NO mechanisms to initiate that:  no khubd
1551  * timer, no SRP, no requests through sysfs.
1552  *
1553  * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
1554  * the root hub for their bus goes into global suspend ... so we don't
1555  * (falsely) update the device power state to say it suspended.
1556  *
1557  * Returns 0 on success, else negative errno.
1558  */
1559 int usb_port_suspend(struct usb_device *udev)
1560 {
1561         struct usb_hub  *hub = hdev_to_hub(udev->parent);
1562         int             port1 = udev->portnum;
1563         int             status;
1564
1565         // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
1566
1567         /* enable remote wakeup when appropriate; this lets the device
1568          * wake up the upstream hub (including maybe the root hub).
1569          *
1570          * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
1571          * we don't explicitly enable it here.
1572          */
1573         if (udev->do_remote_wakeup) {
1574                 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1575                                 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
1576                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1577                                 NULL, 0,
1578                                 USB_CTRL_SET_TIMEOUT);
1579                 if (status)
1580                         dev_dbg(&udev->dev, "won't remote wakeup, status %d\n",
1581                                         status);
1582         }
1583
1584         /* see 7.1.7.6 */
1585         status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
1586         if (status) {
1587                 dev_dbg(hub->intfdev, "can't suspend port %d, status %d\n",
1588                                 port1, status);
1589                 /* paranoia:  "should not happen" */
1590                 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1591                                 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
1592                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1593                                 NULL, 0,
1594                                 USB_CTRL_SET_TIMEOUT);
1595         } else {
1596                 /* device has up to 10 msec to fully suspend */
1597                 dev_dbg(&udev->dev, "usb %ssuspend\n",
1598                                 udev->auto_pm ? "auto-" : "");
1599                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1600                 msleep(10);
1601         }
1602         return status;
1603 }
1604
1605 /*
1606  * If the USB "suspend" state is in use (rather than "global suspend"),
1607  * many devices will be individually taken out of suspend state using
1608  * special "resume" signaling.  This routine kicks in shortly after
1609  * hardware resume signaling is finished, either because of selective
1610  * resume (by host) or remote wakeup (by device) ... now see what changed
1611  * in the tree that's rooted at this device.
1612  *
1613  * If @udev->reset_resume is set then the device is reset before the
1614  * status check is done.
1615  */
1616 static int finish_port_resume(struct usb_device *udev)
1617 {
1618         int     status = 0;
1619         u16     devstatus;
1620
1621         /* caller owns the udev device lock */
1622         dev_dbg(&udev->dev, "finish %sresume\n",
1623                         udev->reset_resume ? "reset-" : "");
1624
1625         /* usb ch9 identifies four variants of SUSPENDED, based on what
1626          * state the device resumes to.  Linux currently won't see the
1627          * first two on the host side; they'd be inside hub_port_init()
1628          * during many timeouts, but khubd can't suspend until later.
1629          */
1630         usb_set_device_state(udev, udev->actconfig
1631                         ? USB_STATE_CONFIGURED
1632                         : USB_STATE_ADDRESS);
1633
1634         /* 10.5.4.5 says not to reset a suspended port if the attached
1635          * device is enabled for remote wakeup.  Hence the reset
1636          * operation is carried out here, after the port has been
1637          * resumed.
1638          */
1639         if (udev->reset_resume)
1640                 status = usb_reset_device(udev);
1641
1642         /* 10.5.4.5 says be sure devices in the tree are still there.
1643          * For now let's assume the device didn't go crazy on resume,
1644          * and device drivers will know about any resume quirks.
1645          */
1646         if (status == 0) {
1647                 devstatus = 0;
1648                 status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
1649                 if (status >= 0)
1650                         status = (status > 0 ? 0 : -ENODEV);
1651         }
1652
1653         if (status) {
1654                 dev_dbg(&udev->dev, "gone after usb resume? status %d\n",
1655                                 status);
1656         } else if (udev->actconfig) {
1657                 le16_to_cpus(&devstatus);
1658                 if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
1659                         status = usb_control_msg(udev,
1660                                         usb_sndctrlpipe(udev, 0),
1661                                         USB_REQ_CLEAR_FEATURE,
1662                                                 USB_RECIP_DEVICE,
1663                                         USB_DEVICE_REMOTE_WAKEUP, 0,
1664                                         NULL, 0,
1665                                         USB_CTRL_SET_TIMEOUT);
1666                         if (status)
1667                                 dev_dbg(&udev->dev, "disable remote "
1668                                         "wakeup, status %d\n", status);
1669                 }
1670                 status = 0;
1671         }
1672         return status;
1673 }
1674
1675 /*
1676  * usb_port_resume - re-activate a suspended usb device's upstream port
1677  * @udev: device to re-activate, not a root hub
1678  * Context: must be able to sleep; device not locked; pm locks held
1679  *
1680  * This will re-activate the suspended device, increasing power usage
1681  * while letting drivers communicate again with its endpoints.
1682  * USB resume explicitly guarantees that the power session between
1683  * the host and the device is the same as it was when the device
1684  * suspended.
1685  *
1686  * If CONFIG_USB_PERSIST and @udev->reset_resume are both set then this
1687  * routine won't check that the port is still enabled.  Furthermore,
1688  * if @udev->reset_resume is set then finish_port_resume() above will
1689  * reset @udev.  The end result is that a broken power session can be
1690  * recovered and @udev will appear to persist across a loss of VBUS power.
1691  *
1692  * For example, if a host controller doesn't maintain VBUS suspend current
1693  * during a system sleep or is reset when the system wakes up, all the USB
1694  * power sessions below it will be broken.  This is especially troublesome
1695  * for mass-storage devices containing mounted filesystems, since the
1696  * device will appear to have disconnected and all the memory mappings
1697  * to it will be lost.  Using the USB_PERSIST facility, the device can be
1698  * made to appear as if it had not disconnected.
1699  *
1700  * This facility is inherently dangerous.  Although usb_reset_device()
1701  * makes every effort to insure that the same device is present after the
1702  * reset as before, it cannot provide a 100% guarantee.  Furthermore it's
1703  * quite possible for a device to remain unaltered but its media to be
1704  * changed.  If the user replaces a flash memory card while the system is
1705  * asleep, he will have only himself to blame when the filesystem on the
1706  * new card is corrupted and the system crashes.
1707  *
1708  * Returns 0 on success, else negative errno.
1709  */
1710 int usb_port_resume(struct usb_device *udev)
1711 {
1712         struct usb_hub  *hub = hdev_to_hub(udev->parent);
1713         int             port1 = udev->portnum;
1714         int             status;
1715         u16             portchange, portstatus;
1716         unsigned        mask_flags, want_flags;
1717
1718         /* Skip the initial Clear-Suspend step for a remote wakeup */
1719         status = hub_port_status(hub, port1, &portstatus, &portchange);
1720         if (status == 0 && !(portstatus & USB_PORT_STAT_SUSPEND))
1721                 goto SuspendCleared;
1722
1723         // dev_dbg(hub->intfdev, "resume port %d\n", port1);
1724
1725         set_bit(port1, hub->busy_bits);
1726
1727         /* see 7.1.7.7; affects power usage, but not budgeting */
1728         status = clear_port_feature(hub->hdev,
1729                         port1, USB_PORT_FEAT_SUSPEND);
1730         if (status) {
1731                 dev_dbg(hub->intfdev, "can't resume port %d, status %d\n",
1732                                 port1, status);
1733         } else {
1734                 /* drive resume for at least 20 msec */
1735                 dev_dbg(&udev->dev, "usb %sresume\n",
1736                                 udev->auto_pm ? "auto-" : "");
1737                 msleep(25);
1738
1739                 /* Virtual root hubs can trigger on GET_PORT_STATUS to
1740                  * stop resume signaling.  Then finish the resume
1741                  * sequence.
1742                  */
1743                 status = hub_port_status(hub, port1, &portstatus, &portchange);
1744
1745  SuspendCleared:
1746                 if (USB_PERSIST && udev->reset_resume)
1747                         want_flags = USB_PORT_STAT_POWER
1748                                         | USB_PORT_STAT_CONNECTION;
1749                 else
1750                         want_flags = USB_PORT_STAT_POWER
1751                                         | USB_PORT_STAT_CONNECTION
1752                                         | USB_PORT_STAT_ENABLE;
1753                 mask_flags = want_flags | USB_PORT_STAT_SUSPEND;
1754
1755                 if (status < 0 || (portstatus & mask_flags) != want_flags) {
1756                         dev_dbg(hub->intfdev,
1757                                 "port %d status %04x.%04x after resume, %d\n",
1758                                 port1, portchange, portstatus, status);
1759                         if (status >= 0)
1760                                 status = -ENODEV;
1761                 } else {
1762                         if (portchange & USB_PORT_STAT_C_SUSPEND)
1763                                 clear_port_feature(hub->hdev, port1,
1764                                                 USB_PORT_FEAT_C_SUSPEND);
1765                         /* TRSMRCY = 10 msec */
1766                         msleep(10);
1767                 }
1768         }
1769
1770         clear_bit(port1, hub->busy_bits);
1771         if (!hub->hdev->parent && !hub->busy_bits[0])
1772                 usb_enable_root_hub_irq(hub->hdev->bus);
1773
1774         if (status == 0)
1775                 status = finish_port_resume(udev);
1776         if (status < 0) {
1777                 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
1778                 hub_port_logical_disconnect(hub, port1);
1779         }
1780         return status;
1781 }
1782
1783 static int remote_wakeup(struct usb_device *udev)
1784 {
1785         int     status = 0;
1786
1787         usb_lock_device(udev);
1788         if (udev->state == USB_STATE_SUSPENDED) {
1789                 dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
1790                 usb_mark_last_busy(udev);
1791                 status = usb_external_resume_device(udev);
1792         }
1793         usb_unlock_device(udev);
1794         return status;
1795 }
1796
1797 #else   /* CONFIG_USB_SUSPEND */
1798
1799 /* When CONFIG_USB_SUSPEND isn't set, we never suspend or resume any ports. */
1800
1801 int usb_port_suspend(struct usb_device *udev)
1802 {
1803         return 0;
1804 }
1805
1806 int usb_port_resume(struct usb_device *udev)
1807 {
1808         int status = 0;
1809
1810         /* However we may need to do a reset-resume */
1811         if (udev->reset_resume) {
1812                 dev_dbg(&udev->dev, "reset-resume\n");
1813                 status = usb_reset_device(udev);
1814         }
1815         return status;
1816 }
1817
1818 static inline int remote_wakeup(struct usb_device *udev)
1819 {
1820         return 0;
1821 }
1822
1823 #endif
1824
1825 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
1826 {
1827         struct usb_hub          *hub = usb_get_intfdata (intf);
1828         struct usb_device       *hdev = hub->hdev;
1829         unsigned                port1;
1830
1831         /* fail if children aren't already suspended */
1832         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1833                 struct usb_device       *udev;
1834
1835                 udev = hdev->children [port1-1];
1836                 if (udev && msg.event == PM_EVENT_SUSPEND &&
1837 #ifdef  CONFIG_USB_SUSPEND
1838                                 udev->state != USB_STATE_SUSPENDED
1839 #else
1840                                 udev->dev.power.power_state.event
1841                                         == PM_EVENT_ON
1842 #endif
1843                                 ) {
1844                         if (!hdev->auto_pm)
1845                                 dev_dbg(&intf->dev, "port %d nyet suspended\n",
1846                                                 port1);
1847                         return -EBUSY;
1848                 }
1849         }
1850
1851         dev_dbg(&intf->dev, "%s\n", __FUNCTION__);
1852
1853         /* stop khubd and related activity */
1854         hub_quiesce(hub);
1855         return 0;
1856 }
1857
1858 static int hub_resume(struct usb_interface *intf)
1859 {
1860         struct usb_hub          *hub = usb_get_intfdata (intf);
1861
1862         dev_dbg(&intf->dev, "%s\n", __FUNCTION__);
1863
1864         /* tell khubd to look for changes on this hub */
1865         hub_activate(hub);
1866         return 0;
1867 }
1868
1869 static int hub_reset_resume(struct usb_interface *intf)
1870 {
1871         struct usb_hub *hub = usb_get_intfdata(intf);
1872         struct usb_device *hdev = hub->hdev;
1873         int port1;
1874
1875         hub_power_on(hub);
1876
1877         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
1878                 struct usb_device *child = hdev->children[port1-1];
1879
1880                 if (child) {
1881
1882                         /* For "USB_PERSIST"-enabled children we must
1883                          * mark the child device for reset-resume and
1884                          * turn off the connect-change status to prevent
1885                          * khubd from disconnecting it later.
1886                          */
1887                         if (USB_PERSIST && child->persist_enabled) {
1888                                 child->reset_resume = 1;
1889                                 clear_port_feature(hdev, port1,
1890                                                 USB_PORT_FEAT_C_CONNECTION);
1891
1892                         /* Otherwise we must disconnect the child,
1893                          * but as we may not lock the child device here
1894                          * we have to do a "logical" disconnect.
1895                          */
1896                         } else {
1897                                 hub_port_logical_disconnect(hub, port1);
1898                         }
1899                 }
1900         }
1901
1902         hub_activate(hub);
1903         return 0;
1904 }
1905
1906 /**
1907  * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
1908  * @rhdev: struct usb_device for the root hub
1909  *
1910  * The USB host controller driver calls this function when its root hub
1911  * is resumed and Vbus power has been interrupted or the controller
1912  * has been reset.  The routine marks @rhdev as having lost power.  When
1913  * the hub driver is resumed it will take notice; if CONFIG_USB_PERSIST
1914  * is enabled then it will carry out power-session recovery, otherwise
1915  * it will disconnect all the child devices.
1916  */
1917 void usb_root_hub_lost_power(struct usb_device *rhdev)
1918 {
1919         dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
1920         rhdev->reset_resume = 1;
1921 }
1922 EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
1923
1924 #else   /* CONFIG_PM */
1925
1926 static inline int remote_wakeup(struct usb_device *udev)
1927 {
1928         return 0;
1929 }
1930
1931 #define hub_suspend             NULL
1932 #define hub_resume              NULL
1933 #define hub_reset_resume        NULL
1934 #endif
1935
1936
1937 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
1938  *
1939  * Between connect detection and reset signaling there must be a delay
1940  * of 100ms at least for debounce and power-settling.  The corresponding
1941  * timer shall restart whenever the downstream port detects a disconnect.
1942  * 
1943  * Apparently there are some bluetooth and irda-dongles and a number of
1944  * low-speed devices for which this debounce period may last over a second.
1945  * Not covered by the spec - but easy to deal with.
1946  *
1947  * This implementation uses a 1500ms total debounce timeout; if the
1948  * connection isn't stable by then it returns -ETIMEDOUT.  It checks
1949  * every 25ms for transient disconnects.  When the port status has been
1950  * unchanged for 100ms it returns the port status.
1951  */
1952
1953 #define HUB_DEBOUNCE_TIMEOUT    1500
1954 #define HUB_DEBOUNCE_STEP         25
1955 #define HUB_DEBOUNCE_STABLE      100
1956
1957 static int hub_port_debounce(struct usb_hub *hub, int port1)
1958 {
1959         int ret;
1960         int total_time, stable_time = 0;
1961         u16 portchange, portstatus;
1962         unsigned connection = 0xffff;
1963
1964         for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
1965                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1966                 if (ret < 0)
1967                         return ret;
1968
1969                 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
1970                      (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
1971                         stable_time += HUB_DEBOUNCE_STEP;
1972                         if (stable_time >= HUB_DEBOUNCE_STABLE)
1973                                 break;
1974                 } else {
1975                         stable_time = 0;
1976                         connection = portstatus & USB_PORT_STAT_CONNECTION;
1977                 }
1978
1979                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
1980                         clear_port_feature(hub->hdev, port1,
1981                                         USB_PORT_FEAT_C_CONNECTION);
1982                 }
1983
1984                 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
1985                         break;
1986                 msleep(HUB_DEBOUNCE_STEP);
1987         }
1988
1989         dev_dbg (hub->intfdev,
1990                 "debounce: port %d: total %dms stable %dms status 0x%x\n",
1991                 port1, total_time, stable_time, portstatus);
1992
1993         if (stable_time < HUB_DEBOUNCE_STABLE)
1994                 return -ETIMEDOUT;
1995         return portstatus;
1996 }
1997
1998 static void ep0_reinit(struct usb_device *udev)
1999 {
2000         usb_disable_endpoint(udev, 0 + USB_DIR_IN);
2001         usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
2002         udev->ep_in[0] = udev->ep_out[0] = &udev->ep0;
2003 }
2004
2005 #define usb_sndaddr0pipe()      (PIPE_CONTROL << 30)
2006 #define usb_rcvaddr0pipe()      ((PIPE_CONTROL << 30) | USB_DIR_IN)
2007
2008 static int hub_set_address(struct usb_device *udev)
2009 {
2010         int retval;
2011
2012         if (udev->devnum == 0)
2013                 return -EINVAL;
2014         if (udev->state == USB_STATE_ADDRESS)
2015                 return 0;
2016         if (udev->state != USB_STATE_DEFAULT)
2017                 return -EINVAL;
2018         retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2019                 USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
2020                 NULL, 0, USB_CTRL_SET_TIMEOUT);
2021         if (retval == 0) {
2022                 usb_set_device_state(udev, USB_STATE_ADDRESS);
2023                 ep0_reinit(udev);
2024         }
2025         return retval;
2026 }
2027
2028 /* Reset device, (re)assign address, get device descriptor.
2029  * Device connection must be stable, no more debouncing needed.
2030  * Returns device in USB_STATE_ADDRESS, except on error.
2031  *
2032  * If this is called for an already-existing device (as part of
2033  * usb_reset_device), the caller must own the device lock.  For a
2034  * newly detected device that is not accessible through any global
2035  * pointers, it's not necessary to lock the device.
2036  */
2037 static int
2038 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2039                 int retry_counter)
2040 {
2041         static DEFINE_MUTEX(usb_address0_mutex);
2042
2043         struct usb_device       *hdev = hub->hdev;
2044         int                     i, j, retval;
2045         unsigned                delay = HUB_SHORT_RESET_TIME;
2046         enum usb_device_speed   oldspeed = udev->speed;
2047         char                    *speed, *type;
2048
2049         /* root hub ports have a slightly longer reset period
2050          * (from USB 2.0 spec, section 7.1.7.5)
2051          */
2052         if (!hdev->parent) {
2053                 delay = HUB_ROOT_RESET_TIME;
2054                 if (port1 == hdev->bus->otg_port)
2055                         hdev->bus->b_hnp_enable = 0;
2056         }
2057
2058         /* Some low speed devices have problems with the quick delay, so */
2059         /*  be a bit pessimistic with those devices. RHbug #23670 */
2060         if (oldspeed == USB_SPEED_LOW)
2061                 delay = HUB_LONG_RESET_TIME;
2062
2063         mutex_lock(&usb_address0_mutex);
2064
2065         /* Reset the device; full speed may morph to high speed */
2066         retval = hub_port_reset(hub, port1, udev, delay);
2067         if (retval < 0)         /* error or disconnect */
2068                 goto fail;
2069                                 /* success, speed is known */
2070         retval = -ENODEV;
2071
2072         if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2073                 dev_dbg(&udev->dev, "device reset changed speed!\n");
2074                 goto fail;
2075         }
2076         oldspeed = udev->speed;
2077   
2078         /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2079          * it's fixed size except for full speed devices.
2080          * For Wireless USB devices, ep0 max packet is always 512 (tho
2081          * reported as 0xff in the device descriptor). WUSB1.0[4.8.1].
2082          */
2083         switch (udev->speed) {
2084         case USB_SPEED_VARIABLE:        /* fixed at 512 */
2085                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(512);
2086                 break;
2087         case USB_SPEED_HIGH:            /* fixed at 64 */
2088                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2089                 break;
2090         case USB_SPEED_FULL:            /* 8, 16, 32, or 64 */
2091                 /* to determine the ep0 maxpacket size, try to read
2092                  * the device descriptor to get bMaxPacketSize0 and
2093                  * then correct our initial guess.
2094                  */
2095                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2096                 break;
2097         case USB_SPEED_LOW:             /* fixed at 8 */
2098                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
2099                 break;
2100         default:
2101                 goto fail;
2102         }
2103  
2104         type = "";
2105         switch (udev->speed) {
2106         case USB_SPEED_LOW:     speed = "low";  break;
2107         case USB_SPEED_FULL:    speed = "full"; break;
2108         case USB_SPEED_HIGH:    speed = "high"; break;
2109         case USB_SPEED_VARIABLE:
2110                                 speed = "variable";
2111                                 type = "Wireless ";
2112                                 break;
2113         default:                speed = "?";    break;
2114         }
2115         dev_info (&udev->dev,
2116                   "%s %s speed %sUSB device using %s and address %d\n",
2117                   (udev->config) ? "reset" : "new", speed, type,
2118                   udev->bus->controller->driver->name, udev->devnum);
2119
2120         /* Set up TT records, if needed  */
2121         if (hdev->tt) {
2122                 udev->tt = hdev->tt;
2123                 udev->ttport = hdev->ttport;
2124         } else if (udev->speed != USB_SPEED_HIGH
2125                         && hdev->speed == USB_SPEED_HIGH) {
2126                 udev->tt = &hub->tt;
2127                 udev->ttport = port1;
2128         }
2129  
2130         /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2131          * Because device hardware and firmware is sometimes buggy in
2132          * this area, and this is how Linux has done it for ages.
2133          * Change it cautiously.
2134          *
2135          * NOTE:  If USE_NEW_SCHEME() is true we will start by issuing
2136          * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
2137          * so it may help with some non-standards-compliant devices.
2138          * Otherwise we start with SET_ADDRESS and then try to read the
2139          * first 8 bytes of the device descriptor to get the ep0 maxpacket
2140          * value.
2141          */
2142         for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2143                 if (USE_NEW_SCHEME(retry_counter)) {
2144                         struct usb_device_descriptor *buf;
2145                         int r = 0;
2146
2147 #define GET_DESCRIPTOR_BUFSIZE  64
2148                         buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2149                         if (!buf) {
2150                                 retval = -ENOMEM;
2151                                 continue;
2152                         }
2153
2154                         /* Retry on all errors; some devices are flakey.
2155                          * 255 is for WUSB devices, we actually need to use
2156                          * 512 (WUSB1.0[4.8.1]).
2157                          */
2158                         for (j = 0; j < 3; ++j) {
2159                                 buf->bMaxPacketSize0 = 0;
2160                                 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2161                                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2162                                         USB_DT_DEVICE << 8, 0,
2163                                         buf, GET_DESCRIPTOR_BUFSIZE,
2164                                         USB_CTRL_GET_TIMEOUT);
2165                                 switch (buf->bMaxPacketSize0) {
2166                                 case 8: case 16: case 32: case 64: case 255:
2167                                         if (buf->bDescriptorType ==
2168                                                         USB_DT_DEVICE) {
2169                                                 r = 0;
2170                                                 break;
2171                                         }
2172                                         /* FALL THROUGH */
2173                                 default:
2174                                         if (r == 0)
2175                                                 r = -EPROTO;
2176                                         break;
2177                                 }
2178                                 if (r == 0)
2179                                         break;
2180                         }
2181                         udev->descriptor.bMaxPacketSize0 =
2182                                         buf->bMaxPacketSize0;
2183                         kfree(buf);
2184
2185                         retval = hub_port_reset(hub, port1, udev, delay);
2186                         if (retval < 0)         /* error or disconnect */
2187                                 goto fail;
2188                         if (oldspeed != udev->speed) {
2189                                 dev_dbg(&udev->dev,
2190                                         "device reset changed speed!\n");
2191                                 retval = -ENODEV;
2192                                 goto fail;
2193                         }
2194                         if (r) {
2195                                 dev_err(&udev->dev, "device descriptor "
2196                                                 "read/%s, error %d\n",
2197                                                 "64", r);
2198                                 retval = -EMSGSIZE;
2199                                 continue;
2200                         }
2201 #undef GET_DESCRIPTOR_BUFSIZE
2202                 }
2203
2204                 for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2205                         retval = hub_set_address(udev);
2206                         if (retval >= 0)
2207                                 break;
2208                         msleep(200);
2209                 }
2210                 if (retval < 0) {
2211                         dev_err(&udev->dev,
2212                                 "device not accepting address %d, error %d\n",
2213                                 udev->devnum, retval);
2214                         goto fail;
2215                 }
2216  
2217                 /* cope with hardware quirkiness:
2218                  *  - let SET_ADDRESS settle, some device hardware wants it
2219                  *  - read ep0 maxpacket even for high and low speed,
2220                  */
2221                 msleep(10);
2222                 if (USE_NEW_SCHEME(retry_counter))
2223                         break;
2224
2225                 retval = usb_get_device_descriptor(udev, 8);
2226                 if (retval < 8) {
2227                         dev_err(&udev->dev, "device descriptor "
2228                                         "read/%s, error %d\n",
2229                                         "8", retval);
2230                         if (retval >= 0)
2231                                 retval = -EMSGSIZE;
2232                 } else {
2233                         retval = 0;
2234                         break;
2235                 }
2236         }
2237         if (retval)
2238                 goto fail;
2239
2240         i = udev->descriptor.bMaxPacketSize0 == 0xff?
2241             512 : udev->descriptor.bMaxPacketSize0;
2242         if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2243                 if (udev->speed != USB_SPEED_FULL ||
2244                                 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2245                         dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
2246                         retval = -EMSGSIZE;
2247                         goto fail;
2248                 }
2249                 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2250                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2251                 ep0_reinit(udev);
2252         }
2253   
2254         retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2255         if (retval < (signed)sizeof(udev->descriptor)) {
2256                 dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
2257                         "all", retval);
2258                 if (retval >= 0)
2259                         retval = -ENOMSG;
2260                 goto fail;
2261         }
2262
2263         retval = 0;
2264
2265 fail:
2266         if (retval)
2267                 hub_port_disable(hub, port1, 0);
2268         mutex_unlock(&usb_address0_mutex);
2269         return retval;
2270 }
2271
2272 static void
2273 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2274 {
2275         struct usb_qualifier_descriptor *qual;
2276         int                             status;
2277
2278         qual = kmalloc (sizeof *qual, GFP_KERNEL);
2279         if (qual == NULL)
2280                 return;
2281
2282         status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2283                         qual, sizeof *qual);
2284         if (status == sizeof *qual) {
2285                 dev_info(&udev->dev, "not running at top speed; "
2286                         "connect to a high speed hub\n");
2287                 /* hub LEDs are probably harder to miss than syslog */
2288                 if (hub->has_indicators) {
2289                         hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2290                         schedule_delayed_work (&hub->leds, 0);
2291                 }
2292         }
2293         kfree(qual);
2294 }
2295
2296 static unsigned
2297 hub_power_remaining (struct usb_hub *hub)
2298 {
2299         struct usb_device *hdev = hub->hdev;
2300         int remaining;
2301         int port1;
2302
2303         if (!hub->limited_power)
2304                 return 0;
2305
2306         remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
2307         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
2308                 struct usb_device       *udev = hdev->children[port1 - 1];
2309                 int                     delta;
2310
2311                 if (!udev)
2312                         continue;
2313
2314                 /* Unconfigured devices may not use more than 100mA,
2315                  * or 8mA for OTG ports */
2316                 if (udev->actconfig)
2317                         delta = udev->actconfig->desc.bMaxPower * 2;
2318                 else if (port1 != udev->bus->otg_port || hdev->parent)
2319                         delta = 100;
2320                 else
2321                         delta = 8;
2322                 if (delta > hub->mA_per_port)
2323                         dev_warn(&udev->dev, "%dmA is over %umA budget "
2324                                         "for port %d!\n",
2325                                         delta, hub->mA_per_port, port1);
2326                 remaining -= delta;
2327         }
2328         if (remaining < 0) {
2329                 dev_warn(hub->intfdev, "%dmA over power budget!\n",
2330                         - remaining);
2331                 remaining = 0;
2332         }
2333         return remaining;
2334 }
2335
2336 /* Handle physical or logical connection change events.
2337  * This routine is called when:
2338  *      a port connection-change occurs;
2339  *      a port enable-change occurs (often caused by EMI);
2340  *      usb_reset_device() encounters changed descriptors (as from
2341  *              a firmware download)
2342  * caller already locked the hub
2343  */
2344 static void hub_port_connect_change(struct usb_hub *hub, int port1,
2345                                         u16 portstatus, u16 portchange)
2346 {
2347         struct usb_device *hdev = hub->hdev;
2348         struct device *hub_dev = hub->intfdev;
2349         u16 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
2350         int status, i;
2351  
2352         dev_dbg (hub_dev,
2353                 "port %d, status %04x, change %04x, %s\n",
2354                 port1, portstatus, portchange, portspeed (portstatus));
2355
2356         if (hub->has_indicators) {
2357                 set_port_led(hub, port1, HUB_LED_AUTO);
2358                 hub->indicator[port1-1] = INDICATOR_AUTO;
2359         }
2360  
2361         /* Disconnect any existing devices under this port */
2362         if (hdev->children[port1-1])
2363                 usb_disconnect(&hdev->children[port1-1]);
2364         clear_bit(port1, hub->change_bits);
2365
2366 #ifdef  CONFIG_USB_OTG
2367         /* during HNP, don't repeat the debounce */
2368         if (hdev->bus->is_b_host)
2369                 portchange &= ~USB_PORT_STAT_C_CONNECTION;
2370 #endif
2371
2372         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2373                 status = hub_port_debounce(hub, port1);
2374                 if (status < 0) {
2375                         if (printk_ratelimit())
2376                                 dev_err (hub_dev, "connect-debounce failed, "
2377                                                 "port %d disabled\n", port1);
2378                         goto done;
2379                 }
2380                 portstatus = status;
2381         }
2382
2383         /* Return now if nothing is connected */
2384         if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2385
2386                 /* maybe switch power back on (e.g. root hub was reset) */
2387                 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2
2388                                 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
2389                         set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
2390  
2391                 if (portstatus & USB_PORT_STAT_ENABLE)
2392                         goto done;
2393                 return;
2394         }
2395
2396         for (i = 0; i < SET_CONFIG_TRIES; i++) {
2397                 struct usb_device *udev;
2398
2399                 /* reallocate for each attempt, since references
2400                  * to the previous one can escape in various ways
2401                  */
2402                 udev = usb_alloc_dev(hdev, hdev->bus, port1);
2403                 if (!udev) {
2404                         dev_err (hub_dev,
2405                                 "couldn't allocate port %d usb_device\n",
2406                                 port1);
2407                         goto done;
2408                 }
2409
2410                 usb_set_device_state(udev, USB_STATE_POWERED);
2411                 udev->speed = USB_SPEED_UNKNOWN;
2412                 udev->bus_mA = hub->mA_per_port;
2413                 udev->level = hdev->level + 1;
2414
2415                 /* set the address */
2416                 choose_address(udev);
2417                 if (udev->devnum <= 0) {
2418                         status = -ENOTCONN;     /* Don't retry */
2419                         goto loop;
2420                 }
2421
2422                 /* reset and get descriptor */
2423                 status = hub_port_init(hub, udev, port1, i);
2424                 if (status < 0)
2425                         goto loop;
2426
2427                 /* consecutive bus-powered hubs aren't reliable; they can
2428                  * violate the voltage drop budget.  if the new child has
2429                  * a "powered" LED, users should notice we didn't enable it
2430                  * (without reading syslog), even without per-port LEDs
2431                  * on the parent.
2432                  */
2433                 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
2434                                 && udev->bus_mA <= 100) {
2435                         u16     devstat;
2436
2437                         status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
2438                                         &devstat);
2439                         if (status < 2) {
2440                                 dev_dbg(&udev->dev, "get status %d ?\n", status);
2441                                 goto loop_disable;
2442                         }
2443                         le16_to_cpus(&devstat);
2444                         if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
2445                                 dev_err(&udev->dev,
2446                                         "can't connect bus-powered hub "
2447                                         "to this port\n");
2448                                 if (hub->has_indicators) {
2449                                         hub->indicator[port1-1] =
2450                                                 INDICATOR_AMBER_BLINK;
2451                                         schedule_delayed_work (&hub->leds, 0);
2452                                 }
2453                                 status = -ENOTCONN;     /* Don't retry */
2454                                 goto loop_disable;
2455                         }
2456                 }
2457  
2458                 /* check for devices running slower than they could */
2459                 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
2460                                 && udev->speed == USB_SPEED_FULL
2461                                 && highspeed_hubs != 0)
2462                         check_highspeed (hub, udev, port1);
2463
2464                 /* Store the parent's children[] pointer.  At this point
2465                  * udev becomes globally accessible, although presumably
2466                  * no one will look at it until hdev is unlocked.
2467                  */
2468                 status = 0;
2469
2470                 /* We mustn't add new devices if the parent hub has
2471                  * been disconnected; we would race with the
2472                  * recursively_mark_NOTATTACHED() routine.
2473                  */
2474                 spin_lock_irq(&device_state_lock);
2475                 if (hdev->state == USB_STATE_NOTATTACHED)
2476                         status = -ENOTCONN;
2477                 else
2478                         hdev->children[port1-1] = udev;
2479                 spin_unlock_irq(&device_state_lock);
2480
2481                 /* Run it through the hoops (find a driver, etc) */
2482                 if (!status) {
2483                         status = usb_new_device(udev);
2484                         if (status) {
2485                                 spin_lock_irq(&device_state_lock);
2486                                 hdev->children[port1-1] = NULL;
2487                                 spin_unlock_irq(&device_state_lock);
2488                         }
2489                 }
2490
2491                 if (status)
2492                         goto loop_disable;
2493
2494                 status = hub_power_remaining(hub);
2495                 if (status)
2496                         dev_dbg(hub_dev, "%dmA power budget left\n", status);
2497
2498                 return;
2499
2500 loop_disable:
2501                 hub_port_disable(hub, port1, 1);
2502 loop:
2503                 ep0_reinit(udev);
2504                 release_address(udev);
2505                 usb_put_dev(udev);
2506                 if ((status == -ENOTCONN) || (status == -ENOTSUPP))
2507                         break;
2508         }
2509  
2510 done:
2511         hub_port_disable(hub, port1, 1);
2512 }
2513
2514 static void hub_events(void)
2515 {
2516         struct list_head *tmp;
2517         struct usb_device *hdev;
2518         struct usb_interface *intf;
2519         struct usb_hub *hub;
2520         struct device *hub_dev;
2521         u16 hubstatus;
2522         u16 hubchange;
2523         u16 portstatus;
2524         u16 portchange;
2525         int i, ret;
2526         int connect_change;
2527
2528         /*
2529          *  We restart the list every time to avoid a deadlock with
2530          * deleting hubs downstream from this one. This should be
2531          * safe since we delete the hub from the event list.
2532          * Not the most efficient, but avoids deadlocks.
2533          */
2534         while (1) {
2535
2536                 /* Grab the first entry at the beginning of the list */
2537                 spin_lock_irq(&hub_event_lock);
2538                 if (list_empty(&hub_event_list)) {
2539                         spin_unlock_irq(&hub_event_lock);
2540                         break;
2541                 }
2542
2543                 tmp = hub_event_list.next;
2544                 list_del_init(tmp);
2545
2546                 hub = list_entry(tmp, struct usb_hub, event_list);
2547                 kref_get(&hub->kref);
2548                 spin_unlock_irq(&hub_event_lock);
2549
2550                 hdev = hub->hdev;
2551                 hub_dev = hub->intfdev;
2552                 intf = to_usb_interface(hub_dev);
2553                 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
2554                                 hdev->state, hub->descriptor
2555                                         ? hub->descriptor->bNbrPorts
2556                                         : 0,
2557                                 /* NOTE: expects max 15 ports... */
2558                                 (u16) hub->change_bits[0],
2559                                 (u16) hub->event_bits[0]);
2560
2561                 /* Lock the device, then check to see if we were
2562                  * disconnected while waiting for the lock to succeed. */
2563                 usb_lock_device(hdev);
2564                 if (unlikely(hub->disconnected))
2565                         goto loop;
2566
2567                 /* If the hub has died, clean up after it */
2568                 if (hdev->state == USB_STATE_NOTATTACHED) {
2569                         hub->error = -ENODEV;
2570                         hub_pre_reset(intf);
2571                         goto loop;
2572                 }
2573
2574                 /* Autoresume */
2575                 ret = usb_autopm_get_interface(intf);
2576                 if (ret) {
2577                         dev_dbg(hub_dev, "Can't autoresume: %d\n", ret);
2578                         goto loop;
2579                 }
2580
2581                 /* If this is an inactive hub, do nothing */
2582                 if (hub->quiescing)
2583                         goto loop_autopm;
2584
2585                 if (hub->error) {
2586                         dev_dbg (hub_dev, "resetting for error %d\n",
2587                                 hub->error);
2588
2589                         ret = usb_reset_composite_device(hdev, intf);
2590                         if (ret) {
2591                                 dev_dbg (hub_dev,
2592                                         "error resetting hub: %d\n", ret);
2593                                 goto loop_autopm;
2594                         }
2595
2596                         hub->nerrors = 0;
2597                         hub->error = 0;
2598                 }
2599
2600                 /* deal with port status changes */
2601                 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
2602                         if (test_bit(i, hub->busy_bits))
2603                                 continue;
2604                         connect_change = test_bit(i, hub->change_bits);
2605                         if (!test_and_clear_bit(i, hub->event_bits) &&
2606                                         !connect_change && !hub->activating)
2607                                 continue;
2608
2609                         ret = hub_port_status(hub, i,
2610                                         &portstatus, &portchange);
2611                         if (ret < 0)
2612                                 continue;
2613
2614                         if (hub->activating && !hdev->children[i-1] &&
2615                                         (portstatus &
2616                                                 USB_PORT_STAT_CONNECTION))
2617                                 connect_change = 1;
2618
2619                         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2620                                 clear_port_feature(hdev, i,
2621                                         USB_PORT_FEAT_C_CONNECTION);
2622                                 connect_change = 1;
2623                         }
2624
2625                         if (portchange & USB_PORT_STAT_C_ENABLE) {
2626                                 if (!connect_change)
2627                                         dev_dbg (hub_dev,
2628                                                 "port %d enable change, "
2629                                                 "status %08x\n",
2630                                                 i, portstatus);
2631                                 clear_port_feature(hdev, i,
2632                                         USB_PORT_FEAT_C_ENABLE);
2633
2634                                 /*
2635                                  * EM interference sometimes causes badly
2636                                  * shielded USB devices to be shutdown by
2637                                  * the hub, this hack enables them again.
2638                                  * Works at least with mouse driver. 
2639                                  */
2640                                 if (!(portstatus & USB_PORT_STAT_ENABLE)
2641                                     && !connect_change
2642                                     && hdev->children[i-1]) {
2643                                         dev_err (hub_dev,
2644                                             "port %i "
2645                                             "disabled by hub (EMI?), "
2646                                             "re-enabling...\n",
2647                                                 i);
2648                                         connect_change = 1;
2649                                 }
2650                         }
2651
2652                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
2653                                 clear_port_feature(hdev, i,
2654                                         USB_PORT_FEAT_C_SUSPEND);
2655                                 if (hdev->children[i-1]) {
2656                                         ret = remote_wakeup(hdev->
2657                                                         children[i-1]);
2658                                         if (ret < 0)
2659                                                 connect_change = 1;
2660                                 } else {
2661                                         ret = -ENODEV;
2662                                         hub_port_disable(hub, i, 1);
2663                                 }
2664                                 dev_dbg (hub_dev,
2665                                         "resume on port %d, status %d\n",
2666                                         i, ret);
2667                         }
2668                         
2669                         if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
2670                                 dev_err (hub_dev,
2671                                         "over-current change on port %d\n",
2672                                         i);
2673                                 clear_port_feature(hdev, i,
2674                                         USB_PORT_FEAT_C_OVER_CURRENT);
2675                                 hub_power_on(hub);
2676                         }
2677
2678                         if (portchange & USB_PORT_STAT_C_RESET) {
2679                                 dev_dbg (hub_dev,
2680                                         "reset change on port %d\n",
2681                                         i);
2682                                 clear_port_feature(hdev, i,
2683                                         USB_PORT_FEAT_C_RESET);
2684                         }
2685
2686                         if (connect_change)
2687                                 hub_port_connect_change(hub, i,
2688                                                 portstatus, portchange);
2689                 } /* end for i */
2690
2691                 /* deal with hub status changes */
2692                 if (test_and_clear_bit(0, hub->event_bits) == 0)
2693                         ;       /* do nothing */
2694                 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
2695                         dev_err (hub_dev, "get_hub_status failed\n");
2696                 else {
2697                         if (hubchange & HUB_CHANGE_LOCAL_POWER) {
2698                                 dev_dbg (hub_dev, "power change\n");
2699                                 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
2700                                 if (hubstatus & HUB_STATUS_LOCAL_POWER)
2701                                         /* FIXME: Is this always true? */
2702                                         hub->limited_power = 0;
2703                                 else
2704                                         hub->limited_power = 1;
2705                         }
2706                         if (hubchange & HUB_CHANGE_OVERCURRENT) {
2707                                 dev_dbg (hub_dev, "overcurrent change\n");
2708                                 msleep(500);    /* Cool down */
2709                                 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
2710                                 hub_power_on(hub);
2711                         }
2712                 }
2713
2714                 hub->activating = 0;
2715
2716                 /* If this is a root hub, tell the HCD it's okay to
2717                  * re-enable port-change interrupts now. */
2718                 if (!hdev->parent && !hub->busy_bits[0])
2719                         usb_enable_root_hub_irq(hdev->bus);
2720
2721 loop_autopm:
2722                 /* Allow autosuspend if we're not going to run again */
2723                 if (list_empty(&hub->event_list))
2724                         usb_autopm_enable(intf);
2725 loop:
2726                 usb_unlock_device(hdev);
2727                 kref_put(&hub->kref, hub_release);
2728
2729         } /* end while (1) */
2730 }
2731
2732 static int hub_thread(void *__unused)
2733 {
2734         set_freezable();
2735         do {
2736                 hub_events();
2737                 wait_event_interruptible(khubd_wait,
2738                                 !list_empty(&hub_event_list) ||
2739                                 kthread_should_stop());
2740                 try_to_freeze();
2741         } while (!kthread_should_stop() || !list_empty(&hub_event_list));
2742
2743         pr_debug("%s: khubd exiting\n", usbcore_name);
2744         return 0;
2745 }
2746
2747 static struct usb_device_id hub_id_table [] = {
2748     { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
2749       .bDeviceClass = USB_CLASS_HUB},
2750     { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
2751       .bInterfaceClass = USB_CLASS_HUB},
2752     { }                                         /* Terminating entry */
2753 };
2754
2755 MODULE_DEVICE_TABLE (usb, hub_id_table);
2756
2757 static struct usb_driver hub_driver = {
2758         .name =         "hub",
2759         .probe =        hub_probe,
2760         .disconnect =   hub_disconnect,
2761         .suspend =      hub_suspend,
2762         .resume =       hub_resume,
2763         .reset_resume = hub_reset_resume,
2764         .pre_reset =    hub_pre_reset,
2765         .post_reset =   hub_post_reset,
2766         .ioctl =        hub_ioctl,
2767         .id_table =     hub_id_table,
2768         .supports_autosuspend = 1,
2769 };
2770
2771 int usb_hub_init(void)
2772 {
2773         if (usb_register(&hub_driver) < 0) {
2774                 printk(KERN_ERR "%s: can't register hub driver\n",
2775                         usbcore_name);
2776                 return -1;
2777         }
2778
2779         khubd_task = kthread_run(hub_thread, NULL, "khubd");
2780         if (!IS_ERR(khubd_task))
2781                 return 0;
2782
2783         /* Fall through if kernel_thread failed */
2784         usb_deregister(&hub_driver);
2785         printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
2786
2787         return -1;
2788 }
2789
2790 void usb_hub_cleanup(void)
2791 {
2792         kthread_stop(khubd_task);
2793
2794         /*
2795          * Hub resources are freed for us by usb_deregister. It calls
2796          * usb_driver_purge on every device which in turn calls that
2797          * devices disconnect function if it is using this driver.
2798          * The hub_disconnect function takes care of releasing the
2799          * individual hub resources. -greg
2800          */
2801         usb_deregister(&hub_driver);
2802 } /* usb_hub_cleanup() */
2803
2804 static int config_descriptors_changed(struct usb_device *udev)
2805 {
2806         unsigned                        index;
2807         unsigned                        len = 0;
2808         struct usb_config_descriptor    *buf;
2809
2810         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2811                 if (len < le16_to_cpu(udev->config[index].desc.wTotalLength))
2812                         len = le16_to_cpu(udev->config[index].desc.wTotalLength);
2813         }
2814         buf = kmalloc (len, GFP_KERNEL);
2815         if (buf == NULL) {
2816                 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
2817                 /* assume the worst */
2818                 return 1;
2819         }
2820         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2821                 int length;
2822                 int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
2823
2824                 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
2825                                 old_length);
2826                 if (length < old_length) {
2827                         dev_dbg(&udev->dev, "config index %d, error %d\n",
2828                                         index, length);
2829                         break;
2830                 }
2831                 if (memcmp (buf, udev->rawdescriptors[index], old_length)
2832                                 != 0) {
2833                         dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
2834                                 index, buf->bConfigurationValue);
2835                         break;
2836                 }
2837         }
2838         kfree(buf);
2839         return index != udev->descriptor.bNumConfigurations;
2840 }
2841
2842 /**
2843  * usb_reset_device - perform a USB port reset to reinitialize a device
2844  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2845  *
2846  * WARNING - don't use this routine to reset a composite device
2847  * (one with multiple interfaces owned by separate drivers)!
2848  * Use usb_reset_composite_device() instead.
2849  *
2850  * Do a port reset, reassign the device's address, and establish its
2851  * former operating configuration.  If the reset fails, or the device's
2852  * descriptors change from their values before the reset, or the original
2853  * configuration and altsettings cannot be restored, a flag will be set
2854  * telling khubd to pretend the device has been disconnected and then
2855  * re-connected.  All drivers will be unbound, and the device will be
2856  * re-enumerated and probed all over again.
2857  *
2858  * Returns 0 if the reset succeeded, -ENODEV if the device has been
2859  * flagged for logical disconnection, or some other negative error code
2860  * if the reset wasn't even attempted.
2861  *
2862  * The caller must own the device lock.  For example, it's safe to use
2863  * this from a driver probe() routine after downloading new firmware.
2864  * For calls that might not occur during probe(), drivers should lock
2865  * the device using usb_lock_device_for_reset().
2866  *
2867  * Locking exception: This routine may also be called from within an
2868  * autoresume handler.  Such usage won't conflict with other tasks
2869  * holding the device lock because these tasks should always call
2870  * usb_autopm_resume_device(), thereby preventing any unwanted autoresume.
2871  */
2872 int usb_reset_device(struct usb_device *udev)
2873 {
2874         struct usb_device               *parent_hdev = udev->parent;
2875         struct usb_hub                  *parent_hub;
2876         struct usb_device_descriptor    descriptor = udev->descriptor;
2877         int                             i, ret = 0;
2878         int                             port1 = udev->portnum;
2879
2880         if (udev->state == USB_STATE_NOTATTACHED ||
2881                         udev->state == USB_STATE_SUSPENDED) {
2882                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
2883                                 udev->state);
2884                 return -EINVAL;
2885         }
2886
2887         if (!parent_hdev) {
2888                 /* this requires hcd-specific logic; see OHCI hc_restart() */
2889                 dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
2890                 return -EISDIR;
2891         }
2892         parent_hub = hdev_to_hub(parent_hdev);
2893
2894         set_bit(port1, parent_hub->busy_bits);
2895         for (i = 0; i < SET_CONFIG_TRIES; ++i) {
2896
2897                 /* ep0 maxpacket size may change; let the HCD know about it.
2898                  * Other endpoints will be handled by re-enumeration. */
2899                 ep0_reinit(udev);
2900                 ret = hub_port_init(parent_hub, udev, port1, i);
2901                 if (ret >= 0 || ret == -ENOTCONN || ret == -ENODEV)
2902                         break;
2903         }
2904         clear_bit(port1, parent_hub->busy_bits);
2905         if (!parent_hdev->parent && !parent_hub->busy_bits[0])
2906                 usb_enable_root_hub_irq(parent_hdev->bus);
2907
2908         if (ret < 0)
2909                 goto re_enumerate;
2910  
2911         /* Device might have changed firmware (DFU or similar) */
2912         if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
2913                         || config_descriptors_changed (udev)) {
2914                 dev_info(&udev->dev, "device firmware changed\n");
2915                 udev->descriptor = descriptor;  /* for disconnect() calls */
2916                 goto re_enumerate;
2917         }
2918   
2919         if (!udev->actconfig)
2920                 goto done;
2921
2922         ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2923                         USB_REQ_SET_CONFIGURATION, 0,
2924                         udev->actconfig->desc.bConfigurationValue, 0,
2925                         NULL, 0, USB_CTRL_SET_TIMEOUT);
2926         if (ret < 0) {
2927                 dev_err(&udev->dev,
2928                         "can't restore configuration #%d (error=%d)\n",
2929                         udev->actconfig->desc.bConfigurationValue, ret);
2930                 goto re_enumerate;
2931         }
2932         usb_set_device_state(udev, USB_STATE_CONFIGURED);
2933
2934         for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
2935                 struct usb_interface *intf = udev->actconfig->interface[i];
2936                 struct usb_interface_descriptor *desc;
2937
2938                 /* set_interface resets host side toggle even
2939                  * for altsetting zero.  the interface may have no driver.
2940                  */
2941                 desc = &intf->cur_altsetting->desc;
2942                 ret = usb_set_interface(udev, desc->bInterfaceNumber,
2943                         desc->bAlternateSetting);
2944                 if (ret < 0) {
2945                         dev_err(&udev->dev, "failed to restore interface %d "
2946                                 "altsetting %d (error=%d)\n",
2947                                 desc->bInterfaceNumber,
2948                                 desc->bAlternateSetting,
2949                                 ret);
2950                         goto re_enumerate;
2951                 }
2952         }
2953
2954 done:
2955         return 0;
2956  
2957 re_enumerate:
2958         hub_port_logical_disconnect(parent_hub, port1);
2959         return -ENODEV;
2960 }
2961 EXPORT_SYMBOL(usb_reset_device);
2962
2963 /**
2964  * usb_reset_composite_device - warn interface drivers and perform a USB port reset
2965  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2966  * @iface: interface bound to the driver making the request (optional)
2967  *
2968  * Warns all drivers bound to registered interfaces (using their pre_reset
2969  * method), performs the port reset, and then lets the drivers know that
2970  * the reset is over (using their post_reset method).
2971  *
2972  * Return value is the same as for usb_reset_device().
2973  *
2974  * The caller must own the device lock.  For example, it's safe to use
2975  * this from a driver probe() routine after downloading new firmware.
2976  * For calls that might not occur during probe(), drivers should lock
2977  * the device using usb_lock_device_for_reset().
2978  *
2979  * The interface locks are acquired during the pre_reset stage and released
2980  * during the post_reset stage.  However if iface is not NULL and is
2981  * currently being probed, we assume that the caller already owns its
2982  * lock.
2983  */
2984 int usb_reset_composite_device(struct usb_device *udev,
2985                 struct usb_interface *iface)
2986 {
2987         int ret;
2988         struct usb_host_config *config = udev->actconfig;
2989
2990         if (udev->state == USB_STATE_NOTATTACHED ||
2991                         udev->state == USB_STATE_SUSPENDED) {
2992                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
2993                                 udev->state);
2994                 return -EINVAL;
2995         }
2996
2997         /* Prevent autosuspend during the reset */
2998         usb_autoresume_device(udev);
2999
3000         if (iface && iface->condition != USB_INTERFACE_BINDING)
3001                 iface = NULL;
3002
3003         if (config) {
3004                 int i;
3005                 struct usb_interface *cintf;
3006                 struct usb_driver *drv;
3007
3008                 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
3009                         cintf = config->interface[i];
3010                         if (cintf != iface)
3011                                 down(&cintf->dev.sem);
3012                         if (device_is_registered(&cintf->dev) &&
3013                                         cintf->dev.driver) {
3014                                 drv = to_usb_driver(cintf->dev.driver);
3015                                 if (drv->pre_reset)
3016                                         (drv->pre_reset)(cintf);
3017         /* FIXME: Unbind if pre_reset returns an error or isn't defined */
3018                         }
3019                 }
3020         }
3021
3022         ret = usb_reset_device(udev);
3023
3024         if (config) {
3025                 int i;
3026                 struct usb_interface *cintf;
3027                 struct usb_driver *drv;
3028
3029                 for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
3030                         cintf = config->interface[i];
3031                         if (device_is_registered(&cintf->dev) &&
3032                                         cintf->dev.driver) {
3033                                 drv = to_usb_driver(cintf->dev.driver);
3034                                 if (drv->post_reset)
3035                                         (drv->post_reset)(cintf);
3036         /* FIXME: Unbind if post_reset returns an error or isn't defined */
3037                         }
3038                         if (cintf != iface)
3039                                 up(&cintf->dev.sem);
3040                 }
3041         }
3042
3043         usb_autosuspend_device(udev);
3044         return ret;
3045 }
3046 EXPORT_SYMBOL(usb_reset_composite_device);