Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm
[linux-2.6] / drivers / usb / core / hub.c
1 /*
2  * USB hub driver.
3  *
4  * (C) Copyright 1999 Linus Torvalds
5  * (C) Copyright 1999 Johannes Erdfelt
6  * (C) Copyright 1999 Gregory P. Smith
7  * (C) Copyright 2001 Brad Hards (bhards@bigpond.net.au)
8  *
9  */
10
11 #include <linux/kernel.h>
12 #include <linux/errno.h>
13 #include <linux/module.h>
14 #include <linux/moduleparam.h>
15 #include <linux/completion.h>
16 #include <linux/sched.h>
17 #include <linux/list.h>
18 #include <linux/slab.h>
19 #include <linux/ioctl.h>
20 #include <linux/usb.h>
21 #include <linux/usbdevice_fs.h>
22 #include <linux/kthread.h>
23 #include <linux/mutex.h>
24 #include <linux/freezer.h>
25
26 #include <asm/uaccess.h>
27 #include <asm/byteorder.h>
28
29 #include "usb.h"
30 #include "hcd.h"
31 #include "hub.h"
32
33 /* if we are in debug mode, always announce new devices */
34 #ifdef DEBUG
35 #ifndef CONFIG_USB_ANNOUNCE_NEW_DEVICES
36 #define CONFIG_USB_ANNOUNCE_NEW_DEVICES
37 #endif
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 /* Mutual exclusion for EHCI CF initialization.  This interferes with
129  * port reset on some companion controllers.
130  */
131 DECLARE_RWSEM(ehci_cf_port_reset_rwsem);
132 EXPORT_SYMBOL_GPL(ehci_cf_port_reset_rwsem);
133
134
135 static inline char *portspeed(int portstatus)
136 {
137         if (portstatus & (1 << USB_PORT_FEAT_HIGHSPEED))
138                 return "480 Mb/s";
139         else if (portstatus & (1 << USB_PORT_FEAT_LOWSPEED))
140                 return "1.5 Mb/s";
141         else
142                 return "12 Mb/s";
143 }
144
145 /* Note that hdev or one of its children must be locked! */
146 static inline struct usb_hub *hdev_to_hub(struct usb_device *hdev)
147 {
148         return usb_get_intfdata(hdev->actconfig->interface[0]);
149 }
150
151 /* USB 2.0 spec Section 11.24.4.5 */
152 static int get_hub_descriptor(struct usb_device *hdev, void *data, int size)
153 {
154         int i, ret;
155
156         for (i = 0; i < 3; i++) {
157                 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
158                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
159                         USB_DT_HUB << 8, 0, data, size,
160                         USB_CTRL_GET_TIMEOUT);
161                 if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
162                         return ret;
163         }
164         return -EINVAL;
165 }
166
167 /*
168  * USB 2.0 spec Section 11.24.2.1
169  */
170 static int clear_hub_feature(struct usb_device *hdev, int feature)
171 {
172         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
173                 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
174 }
175
176 /*
177  * USB 2.0 spec Section 11.24.2.2
178  */
179 static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
180 {
181         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
182                 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
183                 NULL, 0, 1000);
184 }
185
186 /*
187  * USB 2.0 spec Section 11.24.2.13
188  */
189 static int set_port_feature(struct usb_device *hdev, int port1, int feature)
190 {
191         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
192                 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
193                 NULL, 0, 1000);
194 }
195
196 /*
197  * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
198  * for info about using port indicators
199  */
200 static void set_port_led(
201         struct usb_hub *hub,
202         int port1,
203         int selector
204 )
205 {
206         int status = set_port_feature(hub->hdev, (selector << 8) | port1,
207                         USB_PORT_FEAT_INDICATOR);
208         if (status < 0)
209                 dev_dbg (hub->intfdev,
210                         "port %d indicator %s status %d\n",
211                         port1,
212                         ({ char *s; switch (selector) {
213                         case HUB_LED_AMBER: s = "amber"; break;
214                         case HUB_LED_GREEN: s = "green"; break;
215                         case HUB_LED_OFF: s = "off"; break;
216                         case HUB_LED_AUTO: s = "auto"; break;
217                         default: s = "??"; break;
218                         }; s; }),
219                         status);
220 }
221
222 #define LED_CYCLE_PERIOD        ((2*HZ)/3)
223
224 static void led_work (struct work_struct *work)
225 {
226         struct usb_hub          *hub =
227                 container_of(work, struct usb_hub, leds.work);
228         struct usb_device       *hdev = hub->hdev;
229         unsigned                i;
230         unsigned                changed = 0;
231         int                     cursor = -1;
232
233         if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
234                 return;
235
236         for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
237                 unsigned        selector, mode;
238
239                 /* 30%-50% duty cycle */
240
241                 switch (hub->indicator[i]) {
242                 /* cycle marker */
243                 case INDICATOR_CYCLE:
244                         cursor = i;
245                         selector = HUB_LED_AUTO;
246                         mode = INDICATOR_AUTO;
247                         break;
248                 /* blinking green = sw attention */
249                 case INDICATOR_GREEN_BLINK:
250                         selector = HUB_LED_GREEN;
251                         mode = INDICATOR_GREEN_BLINK_OFF;
252                         break;
253                 case INDICATOR_GREEN_BLINK_OFF:
254                         selector = HUB_LED_OFF;
255                         mode = INDICATOR_GREEN_BLINK;
256                         break;
257                 /* blinking amber = hw attention */
258                 case INDICATOR_AMBER_BLINK:
259                         selector = HUB_LED_AMBER;
260                         mode = INDICATOR_AMBER_BLINK_OFF;
261                         break;
262                 case INDICATOR_AMBER_BLINK_OFF:
263                         selector = HUB_LED_OFF;
264                         mode = INDICATOR_AMBER_BLINK;
265                         break;
266                 /* blink green/amber = reserved */
267                 case INDICATOR_ALT_BLINK:
268                         selector = HUB_LED_GREEN;
269                         mode = INDICATOR_ALT_BLINK_OFF;
270                         break;
271                 case INDICATOR_ALT_BLINK_OFF:
272                         selector = HUB_LED_AMBER;
273                         mode = INDICATOR_ALT_BLINK;
274                         break;
275                 default:
276                         continue;
277                 }
278                 if (selector != HUB_LED_AUTO)
279                         changed = 1;
280                 set_port_led(hub, i + 1, selector);
281                 hub->indicator[i] = mode;
282         }
283         if (!changed && blinkenlights) {
284                 cursor++;
285                 cursor %= hub->descriptor->bNbrPorts;
286                 set_port_led(hub, cursor + 1, HUB_LED_GREEN);
287                 hub->indicator[cursor] = INDICATOR_CYCLE;
288                 changed++;
289         }
290         if (changed)
291                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
292 }
293
294 /* use a short timeout for hub/port status fetches */
295 #define USB_STS_TIMEOUT         1000
296 #define USB_STS_RETRIES         5
297
298 /*
299  * USB 2.0 spec Section 11.24.2.6
300  */
301 static int get_hub_status(struct usb_device *hdev,
302                 struct usb_hub_status *data)
303 {
304         int i, status = -ETIMEDOUT;
305
306         for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
307                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
308                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
309                         data, sizeof(*data), USB_STS_TIMEOUT);
310         }
311         return status;
312 }
313
314 /*
315  * USB 2.0 spec Section 11.24.2.7
316  */
317 static int get_port_status(struct usb_device *hdev, int port1,
318                 struct usb_port_status *data)
319 {
320         int i, status = -ETIMEDOUT;
321
322         for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
323                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
324                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
325                         data, sizeof(*data), USB_STS_TIMEOUT);
326         }
327         return status;
328 }
329
330 static int hub_port_status(struct usb_hub *hub, int port1,
331                 u16 *status, u16 *change)
332 {
333         int ret;
334
335         mutex_lock(&hub->status_mutex);
336         ret = get_port_status(hub->hdev, port1, &hub->status->port);
337         if (ret < 4) {
338                 dev_err(hub->intfdev,
339                         "%s failed (err = %d)\n", __func__, ret);
340                 if (ret >= 0)
341                         ret = -EIO;
342         } else {
343                 *status = le16_to_cpu(hub->status->port.wPortStatus);
344                 *change = le16_to_cpu(hub->status->port.wPortChange);
345                 ret = 0;
346         }
347         mutex_unlock(&hub->status_mutex);
348         return ret;
349 }
350
351 static void kick_khubd(struct usb_hub *hub)
352 {
353         unsigned long   flags;
354
355         /* Suppress autosuspend until khubd runs */
356         to_usb_interface(hub->intfdev)->pm_usage_cnt = 1;
357
358         spin_lock_irqsave(&hub_event_lock, flags);
359         if (!hub->disconnected && list_empty(&hub->event_list)) {
360                 list_add_tail(&hub->event_list, &hub_event_list);
361                 wake_up(&khubd_wait);
362         }
363         spin_unlock_irqrestore(&hub_event_lock, flags);
364 }
365
366 void usb_kick_khubd(struct usb_device *hdev)
367 {
368         /* FIXME: What if hdev isn't bound to the hub driver? */
369         kick_khubd(hdev_to_hub(hdev));
370 }
371
372
373 /* completion function, fires on port status changes and various faults */
374 static void hub_irq(struct urb *urb)
375 {
376         struct usb_hub *hub = urb->context;
377         int status = urb->status;
378         int i;
379         unsigned long bits;
380
381         switch (status) {
382         case -ENOENT:           /* synchronous unlink */
383         case -ECONNRESET:       /* async unlink */
384         case -ESHUTDOWN:        /* hardware going away */
385                 return;
386
387         default:                /* presumably an error */
388                 /* Cause a hub reset after 10 consecutive errors */
389                 dev_dbg (hub->intfdev, "transfer --> %d\n", status);
390                 if ((++hub->nerrors < 10) || hub->error)
391                         goto resubmit;
392                 hub->error = status;
393                 /* FALL THROUGH */
394
395         /* let khubd handle things */
396         case 0:                 /* we got data:  port status changed */
397                 bits = 0;
398                 for (i = 0; i < urb->actual_length; ++i)
399                         bits |= ((unsigned long) ((*hub->buffer)[i]))
400                                         << (i*8);
401                 hub->event_bits[0] = bits;
402                 break;
403         }
404
405         hub->nerrors = 0;
406
407         /* Something happened, let khubd figure it out */
408         kick_khubd(hub);
409
410 resubmit:
411         if (hub->quiescing)
412                 return;
413
414         if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
415                         && status != -ENODEV && status != -EPERM)
416                 dev_err (hub->intfdev, "resubmit --> %d\n", status);
417 }
418
419 /* USB 2.0 spec Section 11.24.2.3 */
420 static inline int
421 hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
422 {
423         return usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
424                                HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
425                                tt, NULL, 0, 1000);
426 }
427
428 /*
429  * enumeration blocks khubd for a long time. we use keventd instead, since
430  * long blocking there is the exception, not the rule.  accordingly, HCDs
431  * talking to TTs must queue control transfers (not just bulk and iso), so
432  * both can talk to the same hub concurrently.
433  */
434 static void hub_tt_kevent (struct work_struct *work)
435 {
436         struct usb_hub          *hub =
437                 container_of(work, struct usb_hub, tt.kevent);
438         unsigned long           flags;
439         int                     limit = 100;
440
441         spin_lock_irqsave (&hub->tt.lock, flags);
442         while (--limit && !list_empty (&hub->tt.clear_list)) {
443                 struct list_head        *temp;
444                 struct usb_tt_clear     *clear;
445                 struct usb_device       *hdev = hub->hdev;
446                 int                     status;
447
448                 temp = hub->tt.clear_list.next;
449                 clear = list_entry (temp, struct usb_tt_clear, clear_list);
450                 list_del (&clear->clear_list);
451
452                 /* drop lock so HCD can concurrently report other TT errors */
453                 spin_unlock_irqrestore (&hub->tt.lock, flags);
454                 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
455                 spin_lock_irqsave (&hub->tt.lock, flags);
456
457                 if (status)
458                         dev_err (&hdev->dev,
459                                 "clear tt %d (%04x) error %d\n",
460                                 clear->tt, clear->devinfo, status);
461                 kfree(clear);
462         }
463         spin_unlock_irqrestore (&hub->tt.lock, flags);
464 }
465
466 /**
467  * usb_hub_tt_clear_buffer - clear control/bulk TT state in high speed hub
468  * @udev: the device whose split transaction failed
469  * @pipe: identifies the endpoint of the failed transaction
470  *
471  * High speed HCDs use this to tell the hub driver that some split control or
472  * bulk transaction failed in a way that requires clearing internal state of
473  * a transaction translator.  This is normally detected (and reported) from
474  * interrupt context.
475  *
476  * It may not be possible for that hub to handle additional full (or low)
477  * speed transactions until that state is fully cleared out.
478  */
479 void usb_hub_tt_clear_buffer (struct usb_device *udev, int pipe)
480 {
481         struct usb_tt           *tt = udev->tt;
482         unsigned long           flags;
483         struct usb_tt_clear     *clear;
484
485         /* we've got to cope with an arbitrary number of pending TT clears,
486          * since each TT has "at least two" buffers that can need it (and
487          * there can be many TTs per hub).  even if they're uncommon.
488          */
489         if ((clear = kmalloc (sizeof *clear, GFP_ATOMIC)) == NULL) {
490                 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
491                 /* FIXME recover somehow ... RESET_TT? */
492                 return;
493         }
494
495         /* info that CLEAR_TT_BUFFER needs */
496         clear->tt = tt->multi ? udev->ttport : 1;
497         clear->devinfo = usb_pipeendpoint (pipe);
498         clear->devinfo |= udev->devnum << 4;
499         clear->devinfo |= usb_pipecontrol (pipe)
500                         ? (USB_ENDPOINT_XFER_CONTROL << 11)
501                         : (USB_ENDPOINT_XFER_BULK << 11);
502         if (usb_pipein (pipe))
503                 clear->devinfo |= 1 << 15;
504         
505         /* tell keventd to clear state for this TT */
506         spin_lock_irqsave (&tt->lock, flags);
507         list_add_tail (&clear->clear_list, &tt->clear_list);
508         schedule_work (&tt->kevent);
509         spin_unlock_irqrestore (&tt->lock, flags);
510 }
511 EXPORT_SYMBOL_GPL(usb_hub_tt_clear_buffer);
512
513 static void hub_power_on(struct usb_hub *hub)
514 {
515         int port1;
516         unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
517         u16 wHubCharacteristics =
518                         le16_to_cpu(hub->descriptor->wHubCharacteristics);
519
520         /* Enable power on each port.  Some hubs have reserved values
521          * of LPSM (> 2) in their descriptors, even though they are
522          * USB 2.0 hubs.  Some hubs do not implement port-power switching
523          * but only emulate it.  In all cases, the ports won't work
524          * unless we send these messages to the hub.
525          */
526         if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2)
527                 dev_dbg(hub->intfdev, "enabling power on all ports\n");
528         else
529                 dev_dbg(hub->intfdev, "trying to enable port power on "
530                                 "non-switchable hub\n");
531         for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
532                 set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
533
534         /* Wait at least 100 msec for power to become stable */
535         msleep(max(pgood_delay, (unsigned) 100));
536 }
537
538 static void hub_quiesce(struct usb_hub *hub)
539 {
540         /* (nonblocking) khubd and related activity won't re-trigger */
541         hub->quiescing = 1;
542         hub->activating = 0;
543
544         /* (blocking) stop khubd and related activity */
545         usb_kill_urb(hub->urb);
546         if (hub->has_indicators)
547                 cancel_delayed_work_sync(&hub->leds);
548         if (hub->tt.hub)
549                 cancel_work_sync(&hub->tt.kevent);
550 }
551
552 static void hub_activate(struct usb_hub *hub)
553 {
554         int     status;
555
556         hub->quiescing = 0;
557         hub->activating = 1;
558
559         status = usb_submit_urb(hub->urb, GFP_NOIO);
560         if (status < 0)
561                 dev_err(hub->intfdev, "activate --> %d\n", status);
562         if (hub->has_indicators && blinkenlights)
563                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
564
565         /* scan all ports ASAP */
566         kick_khubd(hub);
567 }
568
569 static int hub_hub_status(struct usb_hub *hub,
570                 u16 *status, u16 *change)
571 {
572         int ret;
573
574         mutex_lock(&hub->status_mutex);
575         ret = get_hub_status(hub->hdev, &hub->status->hub);
576         if (ret < 0)
577                 dev_err (hub->intfdev,
578                         "%s failed (err = %d)\n", __func__, ret);
579         else {
580                 *status = le16_to_cpu(hub->status->hub.wHubStatus);
581                 *change = le16_to_cpu(hub->status->hub.wHubChange); 
582                 ret = 0;
583         }
584         mutex_unlock(&hub->status_mutex);
585         return ret;
586 }
587
588 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
589 {
590         struct usb_device *hdev = hub->hdev;
591         int ret = 0;
592
593         if (hdev->children[port1-1] && set_state)
594                 usb_set_device_state(hdev->children[port1-1],
595                                 USB_STATE_NOTATTACHED);
596         if (!hub->error)
597                 ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
598         if (ret)
599                 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
600                                 port1, ret);
601         return ret;
602 }
603
604 /*
605  * Disable a port and mark a logical connnect-change event, so that some
606  * time later khubd will disconnect() any existing usb_device on the port
607  * and will re-enumerate if there actually is a device attached.
608  */
609 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
610 {
611         dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
612         hub_port_disable(hub, port1, 1);
613
614         /* FIXME let caller ask to power down the port:
615          *  - some devices won't enumerate without a VBUS power cycle
616          *  - SRP saves power that way
617          *  - ... new call, TBD ...
618          * That's easy if this hub can switch power per-port, and
619          * khubd reactivates the port later (timer, SRP, etc).
620          * Powerdown must be optional, because of reset/DFU.
621          */
622
623         set_bit(port1, hub->change_bits);
624         kick_khubd(hub);
625 }
626
627 /* caller has locked the hub device */
628 static void hub_stop(struct usb_hub *hub)
629 {
630         struct usb_device *hdev = hub->hdev;
631         int i;
632
633         /* Disconnect all the children */
634         for (i = 0; i < hdev->maxchild; ++i) {
635                 if (hdev->children[i])
636                         usb_disconnect(&hdev->children[i]);
637         }
638         hub_quiesce(hub);
639 }
640
641 #define HUB_RESET               1
642 #define HUB_RESUME              2
643 #define HUB_RESET_RESUME        3
644
645 #ifdef CONFIG_PM
646
647 /* Try to identify which devices need USB-PERSIST handling */
648 static int persistent_device(struct usb_device *udev)
649 {
650         int i;
651         int retval;
652         struct usb_host_config *actconfig;
653
654         /* Explicitly not marked persistent? */
655         if (!udev->persist_enabled)
656                 return 0;
657
658         /* No active config? */
659         actconfig = udev->actconfig;
660         if (!actconfig)
661                 return 0;
662
663         /* FIXME! We should check whether it's open here or not! */
664
665         /*
666          * Check that all the interface drivers have a
667          * 'reset_resume' entrypoint
668          */
669         retval = 0;
670         for (i = 0; i < actconfig->desc.bNumInterfaces; i++) {
671                 struct usb_interface *intf;
672                 struct usb_driver *driver;
673
674                 intf = actconfig->interface[i];
675                 if (!intf->dev.driver)
676                         continue;
677                 driver = to_usb_driver(intf->dev.driver);
678                 if (!driver->reset_resume)
679                         return 0;
680                 /*
681                  * We have at least one driver, and that one
682                  * has a reset_resume method.
683                  */
684                 retval = 1;
685         }
686         return retval;
687 }
688
689 static void hub_restart(struct usb_hub *hub, int type)
690 {
691         struct usb_device *hdev = hub->hdev;
692         int port1;
693
694         /* Check each of the children to see if they require
695          * USB-PERSIST handling or disconnection.  Also check
696          * each unoccupied port to make sure it is still disabled.
697          */
698         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
699                 struct usb_device *udev = hdev->children[port1-1];
700                 int status = 0;
701                 u16 portstatus, portchange;
702
703                 if (!udev || udev->state == USB_STATE_NOTATTACHED) {
704                         if (type != HUB_RESET) {
705                                 status = hub_port_status(hub, port1,
706                                                 &portstatus, &portchange);
707                                 if (status == 0 && (portstatus &
708                                                 USB_PORT_STAT_ENABLE))
709                                         clear_port_feature(hdev, port1,
710                                                         USB_PORT_FEAT_ENABLE);
711                         }
712                         continue;
713                 }
714
715                 /* Was the power session lost while we were suspended? */
716                 status = hub_port_status(hub, port1, &portstatus, &portchange);
717
718                 /* If the device is gone, khubd will handle it later */
719                 if (status == 0 && !(portstatus & USB_PORT_STAT_CONNECTION))
720                         continue;
721
722                 /* For "USB_PERSIST"-enabled children we must
723                  * mark the child device for reset-resume and
724                  * turn off the various status changes to prevent
725                  * khubd from disconnecting it later.
726                  */
727                 if (status == 0 && !(portstatus & USB_PORT_STAT_ENABLE) &&
728                                 persistent_device(udev)) {
729                         if (portchange & USB_PORT_STAT_C_ENABLE)
730                                 clear_port_feature(hub->hdev, port1,
731                                                 USB_PORT_FEAT_C_ENABLE);
732                         if (portchange & USB_PORT_STAT_C_CONNECTION)
733                                 clear_port_feature(hub->hdev, port1,
734                                                 USB_PORT_FEAT_C_CONNECTION);
735                         udev->reset_resume = 1;
736                 }
737
738                 /* Otherwise for a reset_resume we must disconnect the child,
739                  * but as we may not lock the child device here
740                  * we have to do a "logical" disconnect.
741                  */
742                 else if (type == HUB_RESET_RESUME)
743                         hub_port_logical_disconnect(hub, port1);
744         }
745
746         hub_activate(hub);
747 }
748
749 #endif  /* CONFIG_PM */
750
751 /* caller has locked the hub device */
752 static int hub_pre_reset(struct usb_interface *intf)
753 {
754         struct usb_hub *hub = usb_get_intfdata(intf);
755
756         hub_stop(hub);
757         return 0;
758 }
759
760 /* caller has locked the hub device */
761 static int hub_post_reset(struct usb_interface *intf)
762 {
763         struct usb_hub *hub = usb_get_intfdata(intf);
764
765         hub_power_on(hub);
766         hub_activate(hub);
767         return 0;
768 }
769
770 static int hub_configure(struct usb_hub *hub,
771         struct usb_endpoint_descriptor *endpoint)
772 {
773         struct usb_device *hdev = hub->hdev;
774         struct device *hub_dev = hub->intfdev;
775         u16 hubstatus, hubchange;
776         u16 wHubCharacteristics;
777         unsigned int pipe;
778         int maxp, ret;
779         char *message;
780
781         hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
782                         &hub->buffer_dma);
783         if (!hub->buffer) {
784                 message = "can't allocate hub irq buffer";
785                 ret = -ENOMEM;
786                 goto fail;
787         }
788
789         hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
790         if (!hub->status) {
791                 message = "can't kmalloc hub status buffer";
792                 ret = -ENOMEM;
793                 goto fail;
794         }
795         mutex_init(&hub->status_mutex);
796
797         hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
798         if (!hub->descriptor) {
799                 message = "can't kmalloc hub descriptor";
800                 ret = -ENOMEM;
801                 goto fail;
802         }
803
804         /* Request the entire hub descriptor.
805          * hub->descriptor can handle USB_MAXCHILDREN ports,
806          * but the hub can/will return fewer bytes here.
807          */
808         ret = get_hub_descriptor(hdev, hub->descriptor,
809                         sizeof(*hub->descriptor));
810         if (ret < 0) {
811                 message = "can't read hub descriptor";
812                 goto fail;
813         } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
814                 message = "hub has too many ports!";
815                 ret = -ENODEV;
816                 goto fail;
817         }
818
819         hdev->maxchild = hub->descriptor->bNbrPorts;
820         dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
821                 (hdev->maxchild == 1) ? "" : "s");
822
823         wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
824
825         if (wHubCharacteristics & HUB_CHAR_COMPOUND) {
826                 int     i;
827                 char    portstr [USB_MAXCHILDREN + 1];
828
829                 for (i = 0; i < hdev->maxchild; i++)
830                         portstr[i] = hub->descriptor->DeviceRemovable
831                                     [((i + 1) / 8)] & (1 << ((i + 1) % 8))
832                                 ? 'F' : 'R';
833                 portstr[hdev->maxchild] = 0;
834                 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
835         } else
836                 dev_dbg(hub_dev, "standalone hub\n");
837
838         switch (wHubCharacteristics & HUB_CHAR_LPSM) {
839                 case 0x00:
840                         dev_dbg(hub_dev, "ganged power switching\n");
841                         break;
842                 case 0x01:
843                         dev_dbg(hub_dev, "individual port power switching\n");
844                         break;
845                 case 0x02:
846                 case 0x03:
847                         dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
848                         break;
849         }
850
851         switch (wHubCharacteristics & HUB_CHAR_OCPM) {
852                 case 0x00:
853                         dev_dbg(hub_dev, "global over-current protection\n");
854                         break;
855                 case 0x08:
856                         dev_dbg(hub_dev, "individual port over-current protection\n");
857                         break;
858                 case 0x10:
859                 case 0x18:
860                         dev_dbg(hub_dev, "no over-current protection\n");
861                         break;
862         }
863
864         spin_lock_init (&hub->tt.lock);
865         INIT_LIST_HEAD (&hub->tt.clear_list);
866         INIT_WORK (&hub->tt.kevent, hub_tt_kevent);
867         switch (hdev->descriptor.bDeviceProtocol) {
868                 case 0:
869                         break;
870                 case 1:
871                         dev_dbg(hub_dev, "Single TT\n");
872                         hub->tt.hub = hdev;
873                         break;
874                 case 2:
875                         ret = usb_set_interface(hdev, 0, 1);
876                         if (ret == 0) {
877                                 dev_dbg(hub_dev, "TT per port\n");
878                                 hub->tt.multi = 1;
879                         } else
880                                 dev_err(hub_dev, "Using single TT (err %d)\n",
881                                         ret);
882                         hub->tt.hub = hdev;
883                         break;
884                 default:
885                         dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
886                                 hdev->descriptor.bDeviceProtocol);
887                         break;
888         }
889
890         /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
891         switch (wHubCharacteristics & HUB_CHAR_TTTT) {
892                 case HUB_TTTT_8_BITS:
893                         if (hdev->descriptor.bDeviceProtocol != 0) {
894                                 hub->tt.think_time = 666;
895                                 dev_dbg(hub_dev, "TT requires at most %d "
896                                                 "FS bit times (%d ns)\n",
897                                         8, hub->tt.think_time);
898                         }
899                         break;
900                 case HUB_TTTT_16_BITS:
901                         hub->tt.think_time = 666 * 2;
902                         dev_dbg(hub_dev, "TT requires at most %d "
903                                         "FS bit times (%d ns)\n",
904                                 16, hub->tt.think_time);
905                         break;
906                 case HUB_TTTT_24_BITS:
907                         hub->tt.think_time = 666 * 3;
908                         dev_dbg(hub_dev, "TT requires at most %d "
909                                         "FS bit times (%d ns)\n",
910                                 24, hub->tt.think_time);
911                         break;
912                 case HUB_TTTT_32_BITS:
913                         hub->tt.think_time = 666 * 4;
914                         dev_dbg(hub_dev, "TT requires at most %d "
915                                         "FS bit times (%d ns)\n",
916                                 32, hub->tt.think_time);
917                         break;
918         }
919
920         /* probe() zeroes hub->indicator[] */
921         if (wHubCharacteristics & HUB_CHAR_PORTIND) {
922                 hub->has_indicators = 1;
923                 dev_dbg(hub_dev, "Port indicators are supported\n");
924         }
925
926         dev_dbg(hub_dev, "power on to power good time: %dms\n",
927                 hub->descriptor->bPwrOn2PwrGood * 2);
928
929         /* power budgeting mostly matters with bus-powered hubs,
930          * and battery-powered root hubs (may provide just 8 mA).
931          */
932         ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
933         if (ret < 2) {
934                 message = "can't get hub status";
935                 goto fail;
936         }
937         le16_to_cpus(&hubstatus);
938         if (hdev == hdev->bus->root_hub) {
939                 if (hdev->bus_mA == 0 || hdev->bus_mA >= 500)
940                         hub->mA_per_port = 500;
941                 else {
942                         hub->mA_per_port = hdev->bus_mA;
943                         hub->limited_power = 1;
944                 }
945         } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
946                 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
947                         hub->descriptor->bHubContrCurrent);
948                 hub->limited_power = 1;
949                 if (hdev->maxchild > 0) {
950                         int remaining = hdev->bus_mA -
951                                         hub->descriptor->bHubContrCurrent;
952
953                         if (remaining < hdev->maxchild * 100)
954                                 dev_warn(hub_dev,
955                                         "insufficient power available "
956                                         "to use all downstream ports\n");
957                         hub->mA_per_port = 100;         /* 7.2.1.1 */
958                 }
959         } else {        /* Self-powered external hub */
960                 /* FIXME: What about battery-powered external hubs that
961                  * provide less current per port? */
962                 hub->mA_per_port = 500;
963         }
964         if (hub->mA_per_port < 500)
965                 dev_dbg(hub_dev, "%umA bus power budget for each child\n",
966                                 hub->mA_per_port);
967
968         ret = hub_hub_status(hub, &hubstatus, &hubchange);
969         if (ret < 0) {
970                 message = "can't get hub status";
971                 goto fail;
972         }
973
974         /* local power status reports aren't always correct */
975         if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
976                 dev_dbg(hub_dev, "local power source is %s\n",
977                         (hubstatus & HUB_STATUS_LOCAL_POWER)
978                         ? "lost (inactive)" : "good");
979
980         if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
981                 dev_dbg(hub_dev, "%sover-current condition exists\n",
982                         (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
983
984         /* set up the interrupt endpoint
985          * We use the EP's maxpacket size instead of (PORTS+1+7)/8
986          * bytes as USB2.0[11.12.3] says because some hubs are known
987          * to send more data (and thus cause overflow). For root hubs,
988          * maxpktsize is defined in hcd.c's fake endpoint descriptors
989          * to be big enough for at least USB_MAXCHILDREN ports. */
990         pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
991         maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
992
993         if (maxp > sizeof(*hub->buffer))
994                 maxp = sizeof(*hub->buffer);
995
996         hub->urb = usb_alloc_urb(0, GFP_KERNEL);
997         if (!hub->urb) {
998                 message = "couldn't allocate interrupt urb";
999                 ret = -ENOMEM;
1000                 goto fail;
1001         }
1002
1003         usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
1004                 hub, endpoint->bInterval);
1005         hub->urb->transfer_dma = hub->buffer_dma;
1006         hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1007
1008         /* maybe cycle the hub leds */
1009         if (hub->has_indicators && blinkenlights)
1010                 hub->indicator [0] = INDICATOR_CYCLE;
1011
1012         hub_power_on(hub);
1013         hub_activate(hub);
1014         return 0;
1015
1016 fail:
1017         dev_err (hub_dev, "config failed, %s (err %d)\n",
1018                         message, ret);
1019         /* hub_disconnect() frees urb and descriptor */
1020         return ret;
1021 }
1022
1023 static void hub_release(struct kref *kref)
1024 {
1025         struct usb_hub *hub = container_of(kref, struct usb_hub, kref);
1026
1027         usb_put_intf(to_usb_interface(hub->intfdev));
1028         kfree(hub);
1029 }
1030
1031 static unsigned highspeed_hubs;
1032
1033 static void hub_disconnect(struct usb_interface *intf)
1034 {
1035         struct usb_hub *hub = usb_get_intfdata (intf);
1036
1037         /* Take the hub off the event list and don't let it be added again */
1038         spin_lock_irq(&hub_event_lock);
1039         list_del_init(&hub->event_list);
1040         hub->disconnected = 1;
1041         spin_unlock_irq(&hub_event_lock);
1042
1043         /* Disconnect all children and quiesce the hub */
1044         hub->error = 0;
1045         hub_stop(hub);
1046
1047         usb_set_intfdata (intf, NULL);
1048
1049         if (hub->hdev->speed == USB_SPEED_HIGH)
1050                 highspeed_hubs--;
1051
1052         usb_free_urb(hub->urb);
1053         kfree(hub->descriptor);
1054         kfree(hub->status);
1055         usb_buffer_free(hub->hdev, sizeof(*hub->buffer), hub->buffer,
1056                         hub->buffer_dma);
1057
1058         kref_put(&hub->kref, hub_release);
1059 }
1060
1061 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
1062 {
1063         struct usb_host_interface *desc;
1064         struct usb_endpoint_descriptor *endpoint;
1065         struct usb_device *hdev;
1066         struct usb_hub *hub;
1067
1068         desc = intf->cur_altsetting;
1069         hdev = interface_to_usbdev(intf);
1070
1071 #ifdef  CONFIG_USB_OTG_BLACKLIST_HUB
1072         if (hdev->parent) {
1073                 dev_warn(&intf->dev, "ignoring external hub\n");
1074                 return -ENODEV;
1075         }
1076 #endif
1077
1078         /* Some hubs have a subclass of 1, which AFAICT according to the */
1079         /*  specs is not defined, but it works */
1080         if ((desc->desc.bInterfaceSubClass != 0) &&
1081             (desc->desc.bInterfaceSubClass != 1)) {
1082 descriptor_error:
1083                 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
1084                 return -EIO;
1085         }
1086
1087         /* Multiple endpoints? What kind of mutant ninja-hub is this? */
1088         if (desc->desc.bNumEndpoints != 1)
1089                 goto descriptor_error;
1090
1091         endpoint = &desc->endpoint[0].desc;
1092
1093         /* If it's not an interrupt in endpoint, we'd better punt! */
1094         if (!usb_endpoint_is_int_in(endpoint))
1095                 goto descriptor_error;
1096
1097         /* We found a hub */
1098         dev_info (&intf->dev, "USB hub found\n");
1099
1100         hub = kzalloc(sizeof(*hub), GFP_KERNEL);
1101         if (!hub) {
1102                 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
1103                 return -ENOMEM;
1104         }
1105
1106         kref_init(&hub->kref);
1107         INIT_LIST_HEAD(&hub->event_list);
1108         hub->intfdev = &intf->dev;
1109         hub->hdev = hdev;
1110         INIT_DELAYED_WORK(&hub->leds, led_work);
1111         usb_get_intf(intf);
1112
1113         usb_set_intfdata (intf, hub);
1114         intf->needs_remote_wakeup = 1;
1115
1116         if (hdev->speed == USB_SPEED_HIGH)
1117                 highspeed_hubs++;
1118
1119         if (hub_configure(hub, endpoint) >= 0)
1120                 return 0;
1121
1122         hub_disconnect (intf);
1123         return -ENODEV;
1124 }
1125
1126 static int
1127 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
1128 {
1129         struct usb_device *hdev = interface_to_usbdev (intf);
1130
1131         /* assert ifno == 0 (part of hub spec) */
1132         switch (code) {
1133         case USBDEVFS_HUB_PORTINFO: {
1134                 struct usbdevfs_hub_portinfo *info = user_data;
1135                 int i;
1136
1137                 spin_lock_irq(&device_state_lock);
1138                 if (hdev->devnum <= 0)
1139                         info->nports = 0;
1140                 else {
1141                         info->nports = hdev->maxchild;
1142                         for (i = 0; i < info->nports; i++) {
1143                                 if (hdev->children[i] == NULL)
1144                                         info->port[i] = 0;
1145                                 else
1146                                         info->port[i] =
1147                                                 hdev->children[i]->devnum;
1148                         }
1149                 }
1150                 spin_unlock_irq(&device_state_lock);
1151
1152                 return info->nports + 1;
1153                 }
1154
1155         default:
1156                 return -ENOSYS;
1157         }
1158 }
1159
1160
1161 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
1162 {
1163         int i;
1164
1165         for (i = 0; i < udev->maxchild; ++i) {
1166                 if (udev->children[i])
1167                         recursively_mark_NOTATTACHED(udev->children[i]);
1168         }
1169         if (udev->state == USB_STATE_SUSPENDED) {
1170                 udev->discon_suspended = 1;
1171                 udev->active_duration -= jiffies;
1172         }
1173         udev->state = USB_STATE_NOTATTACHED;
1174 }
1175
1176 /**
1177  * usb_set_device_state - change a device's current state (usbcore, hcds)
1178  * @udev: pointer to device whose state should be changed
1179  * @new_state: new state value to be stored
1180  *
1181  * udev->state is _not_ fully protected by the device lock.  Although
1182  * most transitions are made only while holding the lock, the state can
1183  * can change to USB_STATE_NOTATTACHED at almost any time.  This
1184  * is so that devices can be marked as disconnected as soon as possible,
1185  * without having to wait for any semaphores to be released.  As a result,
1186  * all changes to any device's state must be protected by the
1187  * device_state_lock spinlock.
1188  *
1189  * Once a device has been added to the device tree, all changes to its state
1190  * should be made using this routine.  The state should _not_ be set directly.
1191  *
1192  * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1193  * Otherwise udev->state is set to new_state, and if new_state is
1194  * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1195  * to USB_STATE_NOTATTACHED.
1196  */
1197 void usb_set_device_state(struct usb_device *udev,
1198                 enum usb_device_state new_state)
1199 {
1200         unsigned long flags;
1201
1202         spin_lock_irqsave(&device_state_lock, flags);
1203         if (udev->state == USB_STATE_NOTATTACHED)
1204                 ;       /* do nothing */
1205         else if (new_state != USB_STATE_NOTATTACHED) {
1206
1207                 /* root hub wakeup capabilities are managed out-of-band
1208                  * and may involve silicon errata ... ignore them here.
1209                  */
1210                 if (udev->parent) {
1211                         if (udev->state == USB_STATE_SUSPENDED
1212                                         || new_state == USB_STATE_SUSPENDED)
1213                                 ;       /* No change to wakeup settings */
1214                         else if (new_state == USB_STATE_CONFIGURED)
1215                                 device_init_wakeup(&udev->dev,
1216                                         (udev->actconfig->desc.bmAttributes
1217                                          & USB_CONFIG_ATT_WAKEUP));
1218                         else
1219                                 device_init_wakeup(&udev->dev, 0);
1220                 }
1221                 if (udev->state == USB_STATE_SUSPENDED &&
1222                         new_state != USB_STATE_SUSPENDED)
1223                         udev->active_duration -= jiffies;
1224                 else if (new_state == USB_STATE_SUSPENDED &&
1225                                 udev->state != USB_STATE_SUSPENDED)
1226                         udev->active_duration += jiffies;
1227                 udev->state = new_state;
1228         } else
1229                 recursively_mark_NOTATTACHED(udev);
1230         spin_unlock_irqrestore(&device_state_lock, flags);
1231 }
1232
1233 /*
1234  * WUSB devices are simple: they have no hubs behind, so the mapping
1235  * device <-> virtual port number becomes 1:1. Why? to simplify the
1236  * life of the device connection logic in
1237  * drivers/usb/wusbcore/devconnect.c. When we do the initial secret
1238  * handshake we need to assign a temporary address in the unauthorized
1239  * space. For simplicity we use the first virtual port number found to
1240  * be free [drivers/usb/wusbcore/devconnect.c:wusbhc_devconnect_ack()]
1241  * and that becomes it's address [X < 128] or its unauthorized address
1242  * [X | 0x80].
1243  *
1244  * We add 1 as an offset to the one-based USB-stack port number
1245  * (zero-based wusb virtual port index) for two reasons: (a) dev addr
1246  * 0 is reserved by USB for default address; (b) Linux's USB stack
1247  * uses always #1 for the root hub of the controller. So USB stack's
1248  * port #1, which is wusb virtual-port #0 has address #2.
1249  */
1250 static void choose_address(struct usb_device *udev)
1251 {
1252         int             devnum;
1253         struct usb_bus  *bus = udev->bus;
1254
1255         /* If khubd ever becomes multithreaded, this will need a lock */
1256         if (udev->wusb) {
1257                 devnum = udev->portnum + 1;
1258                 BUG_ON(test_bit(devnum, bus->devmap.devicemap));
1259         } else {
1260                 /* Try to allocate the next devnum beginning at
1261                  * bus->devnum_next. */
1262                 devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1263                                             bus->devnum_next);
1264                 if (devnum >= 128)
1265                         devnum = find_next_zero_bit(bus->devmap.devicemap,
1266                                                     128, 1);
1267                 bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1268         }
1269         if (devnum < 128) {
1270                 set_bit(devnum, bus->devmap.devicemap);
1271                 udev->devnum = devnum;
1272         }
1273 }
1274
1275 static void release_address(struct usb_device *udev)
1276 {
1277         if (udev->devnum > 0) {
1278                 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1279                 udev->devnum = -1;
1280         }
1281 }
1282
1283 static void update_address(struct usb_device *udev, int devnum)
1284 {
1285         /* The address for a WUSB device is managed by wusbcore. */
1286         if (!udev->wusb)
1287                 udev->devnum = devnum;
1288 }
1289
1290 #ifdef  CONFIG_USB_SUSPEND
1291
1292 static void usb_stop_pm(struct usb_device *udev)
1293 {
1294         /* Synchronize with the ksuspend thread to prevent any more
1295          * autosuspend requests from being submitted, and decrement
1296          * the parent's count of unsuspended children.
1297          */
1298         usb_pm_lock(udev);
1299         if (udev->parent && !udev->discon_suspended)
1300                 usb_autosuspend_device(udev->parent);
1301         usb_pm_unlock(udev);
1302
1303         /* Stop any autosuspend requests already submitted */
1304         cancel_rearming_delayed_work(&udev->autosuspend);
1305 }
1306
1307 #else
1308
1309 static inline void usb_stop_pm(struct usb_device *udev)
1310 { }
1311
1312 #endif
1313
1314 /**
1315  * usb_disconnect - disconnect a device (usbcore-internal)
1316  * @pdev: pointer to device being disconnected
1317  * Context: !in_interrupt ()
1318  *
1319  * Something got disconnected. Get rid of it and all of its children.
1320  *
1321  * If *pdev is a normal device then the parent hub must already be locked.
1322  * If *pdev is a root hub then this routine will acquire the
1323  * usb_bus_list_lock on behalf of the caller.
1324  *
1325  * Only hub drivers (including virtual root hub drivers for host
1326  * controllers) should ever call this.
1327  *
1328  * This call is synchronous, and may not be used in an interrupt context.
1329  */
1330 void usb_disconnect(struct usb_device **pdev)
1331 {
1332         struct usb_device       *udev = *pdev;
1333         int                     i;
1334
1335         if (!udev) {
1336                 pr_debug ("%s nodev\n", __func__);
1337                 return;
1338         }
1339
1340         /* mark the device as inactive, so any further urb submissions for
1341          * this device (and any of its children) will fail immediately.
1342          * this quiesces everyting except pending urbs.
1343          */
1344         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1345         dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1346
1347         usb_lock_device(udev);
1348
1349         /* Free up all the children before we remove this device */
1350         for (i = 0; i < USB_MAXCHILDREN; i++) {
1351                 if (udev->children[i])
1352                         usb_disconnect(&udev->children[i]);
1353         }
1354
1355         /* deallocate hcd/hardware state ... nuking all pending urbs and
1356          * cleaning up all state associated with the current configuration
1357          * so that the hardware is now fully quiesced.
1358          */
1359         dev_dbg (&udev->dev, "unregistering device\n");
1360         usb_disable_device(udev, 0);
1361
1362         usb_unlock_device(udev);
1363
1364         /* Remove the device-specific files from sysfs.  This must be
1365          * done with udev unlocked, because some of the attribute
1366          * routines try to acquire the device lock.
1367          */
1368         usb_remove_sysfs_dev_files(udev);
1369
1370         /* Unregister the device.  The device driver is responsible
1371          * for removing the device files from usbfs and sysfs and for
1372          * de-configuring the device.
1373          */
1374         device_del(&udev->dev);
1375
1376         /* Free the device number and delete the parent's children[]
1377          * (or root_hub) pointer.
1378          */
1379         release_address(udev);
1380
1381         /* Avoid races with recursively_mark_NOTATTACHED() */
1382         spin_lock_irq(&device_state_lock);
1383         *pdev = NULL;
1384         spin_unlock_irq(&device_state_lock);
1385
1386         usb_stop_pm(udev);
1387
1388         put_device(&udev->dev);
1389 }
1390
1391 #ifdef CONFIG_USB_ANNOUNCE_NEW_DEVICES
1392 static void show_string(struct usb_device *udev, char *id, char *string)
1393 {
1394         if (!string)
1395                 return;
1396         dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1397 }
1398
1399 static void announce_device(struct usb_device *udev)
1400 {
1401         dev_info(&udev->dev, "New USB device found, idVendor=%04x, idProduct=%04x\n",
1402                 le16_to_cpu(udev->descriptor.idVendor),
1403                 le16_to_cpu(udev->descriptor.idProduct));
1404         dev_info(&udev->dev, "New USB device strings: Mfr=%d, Product=%d, "
1405                 "SerialNumber=%d\n",
1406                 udev->descriptor.iManufacturer,
1407                 udev->descriptor.iProduct,
1408                 udev->descriptor.iSerialNumber);
1409         show_string(udev, "Product", udev->product);
1410         show_string(udev, "Manufacturer", udev->manufacturer);
1411         show_string(udev, "SerialNumber", udev->serial);
1412 }
1413 #else
1414 static inline void announce_device(struct usb_device *udev) { }
1415 #endif
1416
1417 #ifdef  CONFIG_USB_OTG
1418 #include "otg_whitelist.h"
1419 #endif
1420
1421 /**
1422  * usb_configure_device_otg - FIXME (usbcore-internal)
1423  * @udev: newly addressed device (in ADDRESS state)
1424  *
1425  * Do configuration for On-The-Go devices
1426  */
1427 static int usb_configure_device_otg(struct usb_device *udev)
1428 {
1429         int err = 0;
1430
1431 #ifdef  CONFIG_USB_OTG
1432         /*
1433          * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1434          * to wake us after we've powered off VBUS; and HNP, switching roles
1435          * "host" to "peripheral".  The OTG descriptor helps figure this out.
1436          */
1437         if (!udev->bus->is_b_host
1438                         && udev->config
1439                         && udev->parent == udev->bus->root_hub) {
1440                 struct usb_otg_descriptor       *desc = 0;
1441                 struct usb_bus                  *bus = udev->bus;
1442
1443                 /* descriptor may appear anywhere in config */
1444                 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1445                                         le16_to_cpu(udev->config[0].desc.wTotalLength),
1446                                         USB_DT_OTG, (void **) &desc) == 0) {
1447                         if (desc->bmAttributes & USB_OTG_HNP) {
1448                                 unsigned                port1 = udev->portnum;
1449
1450                                 dev_info(&udev->dev,
1451                                         "Dual-Role OTG device on %sHNP port\n",
1452                                         (port1 == bus->otg_port)
1453                                                 ? "" : "non-");
1454
1455                                 /* enable HNP before suspend, it's simpler */
1456                                 if (port1 == bus->otg_port)
1457                                         bus->b_hnp_enable = 1;
1458                                 err = usb_control_msg(udev,
1459                                         usb_sndctrlpipe(udev, 0),
1460                                         USB_REQ_SET_FEATURE, 0,
1461                                         bus->b_hnp_enable
1462                                                 ? USB_DEVICE_B_HNP_ENABLE
1463                                                 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1464                                         0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1465                                 if (err < 0) {
1466                                         /* OTG MESSAGE: report errors here,
1467                                          * customize to match your product.
1468                                          */
1469                                         dev_info(&udev->dev,
1470                                                 "can't set HNP mode; %d\n",
1471                                                 err);
1472                                         bus->b_hnp_enable = 0;
1473                                 }
1474                         }
1475                 }
1476         }
1477
1478         if (!is_targeted(udev)) {
1479
1480                 /* Maybe it can talk to us, though we can't talk to it.
1481                  * (Includes HNP test device.)
1482                  */
1483                 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1484                         err = usb_port_suspend(udev);
1485                         if (err < 0)
1486                                 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1487                 }
1488                 err = -ENOTSUPP;
1489                 goto fail;
1490         }
1491 fail:
1492 #endif
1493         return err;
1494 }
1495
1496
1497 /**
1498  * usb_configure_device - Detect and probe device intfs/otg (usbcore-internal)
1499  * @udev: newly addressed device (in ADDRESS state)
1500  *
1501  * This is only called by usb_new_device() and usb_authorize_device()
1502  * and FIXME -- all comments that apply to them apply here wrt to
1503  * environment.
1504  *
1505  * If the device is WUSB and not authorized, we don't attempt to read
1506  * the string descriptors, as they will be errored out by the device
1507  * until it has been authorized.
1508  */
1509 static int usb_configure_device(struct usb_device *udev)
1510 {
1511         int err;
1512
1513         if (udev->config == NULL) {
1514                 err = usb_get_configuration(udev);
1515                 if (err < 0) {
1516                         dev_err(&udev->dev, "can't read configurations, error %d\n",
1517                                 err);
1518                         goto fail;
1519                 }
1520         }
1521         if (udev->wusb == 1 && udev->authorized == 0) {
1522                 udev->product = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1523                 udev->manufacturer = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1524                 udev->serial = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1525         }
1526         else {
1527                 /* read the standard strings and cache them if present */
1528                 udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
1529                 udev->manufacturer = usb_cache_string(udev,
1530                                                       udev->descriptor.iManufacturer);
1531                 udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
1532         }
1533         err = usb_configure_device_otg(udev);
1534 fail:
1535         return err;
1536 }
1537
1538
1539 /**
1540  * usb_new_device - perform initial device setup (usbcore-internal)
1541  * @udev: newly addressed device (in ADDRESS state)
1542  *
1543  * This is called with devices which have been enumerated, but not yet
1544  * configured.  The device descriptor is available, but not descriptors
1545  * for any device configuration.  The caller must have locked either
1546  * the parent hub (if udev is a normal device) or else the
1547  * usb_bus_list_lock (if udev is a root hub).  The parent's pointer to
1548  * udev has already been installed, but udev is not yet visible through
1549  * sysfs or other filesystem code.
1550  *
1551  * It will return if the device is configured properly or not.  Zero if
1552  * the interface was registered with the driver core; else a negative
1553  * errno value.
1554  *
1555  * This call is synchronous, and may not be used in an interrupt context.
1556  *
1557  * Only the hub driver or root-hub registrar should ever call this.
1558  */
1559 int usb_new_device(struct usb_device *udev)
1560 {
1561         int err;
1562
1563         usb_detect_quirks(udev);                /* Determine quirks */
1564         err = usb_configure_device(udev);       /* detect & probe dev/intfs */
1565         if (err < 0)
1566                 goto fail;
1567         /* export the usbdev device-node for libusb */
1568         udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
1569                         (((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
1570
1571         /* Increment the parent's count of unsuspended children */
1572         if (udev->parent)
1573                 usb_autoresume_device(udev->parent);
1574
1575         /* Register the device.  The device driver is responsible
1576          * for adding the device files to sysfs and for configuring
1577          * the device.
1578          */
1579         err = device_add(&udev->dev);
1580         if (err) {
1581                 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1582                 goto fail;
1583         }
1584
1585         /* put device-specific files into sysfs */
1586         usb_create_sysfs_dev_files(udev);
1587
1588         /* Tell the world! */
1589         announce_device(udev);
1590         return err;
1591
1592 fail:
1593         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1594         return err;
1595 }
1596
1597
1598 /**
1599  * usb_deauthorize_device - deauthorize a device (usbcore-internal)
1600  * @usb_dev: USB device
1601  *
1602  * Move the USB device to a very basic state where interfaces are disabled
1603  * and the device is in fact unconfigured and unusable.
1604  *
1605  * We share a lock (that we have) with device_del(), so we need to
1606  * defer its call.
1607  */
1608 int usb_deauthorize_device(struct usb_device *usb_dev)
1609 {
1610         unsigned cnt;
1611         usb_lock_device(usb_dev);
1612         if (usb_dev->authorized == 0)
1613                 goto out_unauthorized;
1614         usb_dev->authorized = 0;
1615         usb_set_configuration(usb_dev, -1);
1616         usb_dev->product = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1617         usb_dev->manufacturer = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1618         usb_dev->serial = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1619         kfree(usb_dev->config);
1620         usb_dev->config = NULL;
1621         for (cnt = 0; cnt < usb_dev->descriptor.bNumConfigurations; cnt++)
1622                 kfree(usb_dev->rawdescriptors[cnt]);
1623         usb_dev->descriptor.bNumConfigurations = 0;
1624         kfree(usb_dev->rawdescriptors);
1625 out_unauthorized:
1626         usb_unlock_device(usb_dev);
1627         return 0;
1628 }
1629
1630
1631 int usb_authorize_device(struct usb_device *usb_dev)
1632 {
1633         int result = 0, c;
1634         usb_lock_device(usb_dev);
1635         if (usb_dev->authorized == 1)
1636                 goto out_authorized;
1637         kfree(usb_dev->product);
1638         usb_dev->product = NULL;
1639         kfree(usb_dev->manufacturer);
1640         usb_dev->manufacturer = NULL;
1641         kfree(usb_dev->serial);
1642         usb_dev->serial = NULL;
1643         result = usb_autoresume_device(usb_dev);
1644         if (result < 0) {
1645                 dev_err(&usb_dev->dev,
1646                         "can't autoresume for authorization: %d\n", result);
1647                 goto error_autoresume;
1648         }
1649         result = usb_get_device_descriptor(usb_dev, sizeof(usb_dev->descriptor));
1650         if (result < 0) {
1651                 dev_err(&usb_dev->dev, "can't re-read device descriptor for "
1652                         "authorization: %d\n", result);
1653                 goto error_device_descriptor;
1654         }
1655         usb_dev->authorized = 1;
1656         result = usb_configure_device(usb_dev);
1657         if (result < 0)
1658                 goto error_configure;
1659         /* Choose and set the configuration.  This registers the interfaces
1660          * with the driver core and lets interface drivers bind to them.
1661          */
1662         c = usb_choose_configuration(usb_dev);
1663         if (c >= 0) {
1664                 result = usb_set_configuration(usb_dev, c);
1665                 if (result) {
1666                         dev_err(&usb_dev->dev,
1667                                 "can't set config #%d, error %d\n", c, result);
1668                         /* This need not be fatal.  The user can try to
1669                          * set other configurations. */
1670                 }
1671         }
1672         dev_info(&usb_dev->dev, "authorized to connect\n");
1673 error_configure:
1674 error_device_descriptor:
1675 error_autoresume:
1676 out_authorized:
1677         usb_unlock_device(usb_dev);     // complements locktree
1678         return result;
1679 }
1680
1681
1682 /* Returns 1 if @hub is a WUSB root hub, 0 otherwise */
1683 static unsigned hub_is_wusb(struct usb_hub *hub)
1684 {
1685         struct usb_hcd *hcd;
1686         if (hub->hdev->parent != NULL)  /* not a root hub? */
1687                 return 0;
1688         hcd = container_of(hub->hdev->bus, struct usb_hcd, self);
1689         return hcd->wireless;
1690 }
1691
1692
1693 #define PORT_RESET_TRIES        5
1694 #define SET_ADDRESS_TRIES       2
1695 #define GET_DESCRIPTOR_TRIES    2
1696 #define SET_CONFIG_TRIES        (2 * (use_both_schemes + 1))
1697 #define USE_NEW_SCHEME(i)       ((i) / 2 == old_scheme_first)
1698
1699 #define HUB_ROOT_RESET_TIME     50      /* times are in msec */
1700 #define HUB_SHORT_RESET_TIME    10
1701 #define HUB_LONG_RESET_TIME     200
1702 #define HUB_RESET_TIMEOUT       500
1703
1704 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1705                                 struct usb_device *udev, unsigned int delay)
1706 {
1707         int delay_time, ret;
1708         u16 portstatus;
1709         u16 portchange;
1710
1711         for (delay_time = 0;
1712                         delay_time < HUB_RESET_TIMEOUT;
1713                         delay_time += delay) {
1714                 /* wait to give the device a chance to reset */
1715                 msleep(delay);
1716
1717                 /* read and decode port status */
1718                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1719                 if (ret < 0)
1720                         return ret;
1721
1722                 /* Device went away? */
1723                 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1724                         return -ENOTCONN;
1725
1726                 /* bomb out completely if the connection bounced */
1727                 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1728                         return -ENOTCONN;
1729
1730                 /* if we`ve finished resetting, then break out of the loop */
1731                 if (!(portstatus & USB_PORT_STAT_RESET) &&
1732                     (portstatus & USB_PORT_STAT_ENABLE)) {
1733                         if (hub_is_wusb(hub))
1734                                 udev->speed = USB_SPEED_VARIABLE;
1735                         else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1736                                 udev->speed = USB_SPEED_HIGH;
1737                         else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1738                                 udev->speed = USB_SPEED_LOW;
1739                         else
1740                                 udev->speed = USB_SPEED_FULL;
1741                         return 0;
1742                 }
1743
1744                 /* switch to the long delay after two short delay failures */
1745                 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
1746                         delay = HUB_LONG_RESET_TIME;
1747
1748                 dev_dbg (hub->intfdev,
1749                         "port %d not reset yet, waiting %dms\n",
1750                         port1, delay);
1751         }
1752
1753         return -EBUSY;
1754 }
1755
1756 static int hub_port_reset(struct usb_hub *hub, int port1,
1757                                 struct usb_device *udev, unsigned int delay)
1758 {
1759         int i, status;
1760
1761         /* Block EHCI CF initialization during the port reset.
1762          * Some companion controllers don't like it when they mix.
1763          */
1764         down_read(&ehci_cf_port_reset_rwsem);
1765
1766         /* Reset the port */
1767         for (i = 0; i < PORT_RESET_TRIES; i++) {
1768                 status = set_port_feature(hub->hdev,
1769                                 port1, USB_PORT_FEAT_RESET);
1770                 if (status)
1771                         dev_err(hub->intfdev,
1772                                         "cannot reset port %d (err = %d)\n",
1773                                         port1, status);
1774                 else {
1775                         status = hub_port_wait_reset(hub, port1, udev, delay);
1776                         if (status && status != -ENOTCONN)
1777                                 dev_dbg(hub->intfdev,
1778                                                 "port_wait_reset: err = %d\n",
1779                                                 status);
1780                 }
1781
1782                 /* return on disconnect or reset */
1783                 switch (status) {
1784                 case 0:
1785                         /* TRSTRCY = 10 ms; plus some extra */
1786                         msleep(10 + 40);
1787                         update_address(udev, 0);
1788                         /* FALL THROUGH */
1789                 case -ENOTCONN:
1790                 case -ENODEV:
1791                         clear_port_feature(hub->hdev,
1792                                 port1, USB_PORT_FEAT_C_RESET);
1793                         /* FIXME need disconnect() for NOTATTACHED device */
1794                         usb_set_device_state(udev, status
1795                                         ? USB_STATE_NOTATTACHED
1796                                         : USB_STATE_DEFAULT);
1797                         goto done;
1798                 }
1799
1800                 dev_dbg (hub->intfdev,
1801                         "port %d not enabled, trying reset again...\n",
1802                         port1);
1803                 delay = HUB_LONG_RESET_TIME;
1804         }
1805
1806         dev_err (hub->intfdev,
1807                 "Cannot enable port %i.  Maybe the USB cable is bad?\n",
1808                 port1);
1809
1810  done:
1811         up_read(&ehci_cf_port_reset_rwsem);
1812         return status;
1813 }
1814
1815 #ifdef  CONFIG_PM
1816
1817 #ifdef  CONFIG_USB_SUSPEND
1818
1819 /*
1820  * usb_port_suspend - suspend a usb device's upstream port
1821  * @udev: device that's no longer in active use, not a root hub
1822  * Context: must be able to sleep; device not locked; pm locks held
1823  *
1824  * Suspends a USB device that isn't in active use, conserving power.
1825  * Devices may wake out of a suspend, if anything important happens,
1826  * using the remote wakeup mechanism.  They may also be taken out of
1827  * suspend by the host, using usb_port_resume().  It's also routine
1828  * to disconnect devices while they are suspended.
1829  *
1830  * This only affects the USB hardware for a device; its interfaces
1831  * (and, for hubs, child devices) must already have been suspended.
1832  *
1833  * Selective port suspend reduces power; most suspended devices draw
1834  * less than 500 uA.  It's also used in OTG, along with remote wakeup.
1835  * All devices below the suspended port are also suspended.
1836  *
1837  * Devices leave suspend state when the host wakes them up.  Some devices
1838  * also support "remote wakeup", where the device can activate the USB
1839  * tree above them to deliver data, such as a keypress or packet.  In
1840  * some cases, this wakes the USB host.
1841  *
1842  * Suspending OTG devices may trigger HNP, if that's been enabled
1843  * between a pair of dual-role devices.  That will change roles, such
1844  * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
1845  *
1846  * Devices on USB hub ports have only one "suspend" state, corresponding
1847  * to ACPI D2, "may cause the device to lose some context".
1848  * State transitions include:
1849  *
1850  *   - suspend, resume ... when the VBUS power link stays live
1851  *   - suspend, disconnect ... VBUS lost
1852  *
1853  * Once VBUS drop breaks the circuit, the port it's using has to go through
1854  * normal re-enumeration procedures, starting with enabling VBUS power.
1855  * Other than re-initializing the hub (plug/unplug, except for root hubs),
1856  * Linux (2.6) currently has NO mechanisms to initiate that:  no khubd
1857  * timer, no SRP, no requests through sysfs.
1858  *
1859  * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
1860  * the root hub for their bus goes into global suspend ... so we don't
1861  * (falsely) update the device power state to say it suspended.
1862  *
1863  * Returns 0 on success, else negative errno.
1864  */
1865 int usb_port_suspend(struct usb_device *udev)
1866 {
1867         struct usb_hub  *hub = hdev_to_hub(udev->parent);
1868         int             port1 = udev->portnum;
1869         int             status;
1870
1871         // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
1872
1873         /* enable remote wakeup when appropriate; this lets the device
1874          * wake up the upstream hub (including maybe the root hub).
1875          *
1876          * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
1877          * we don't explicitly enable it here.
1878          */
1879         if (udev->do_remote_wakeup) {
1880                 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1881                                 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
1882                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1883                                 NULL, 0,
1884                                 USB_CTRL_SET_TIMEOUT);
1885                 if (status)
1886                         dev_dbg(&udev->dev, "won't remote wakeup, status %d\n",
1887                                         status);
1888         }
1889
1890         /* see 7.1.7.6 */
1891         status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
1892         if (status) {
1893                 dev_dbg(hub->intfdev, "can't suspend port %d, status %d\n",
1894                                 port1, status);
1895                 /* paranoia:  "should not happen" */
1896                 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1897                                 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
1898                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1899                                 NULL, 0,
1900                                 USB_CTRL_SET_TIMEOUT);
1901         } else {
1902                 /* device has up to 10 msec to fully suspend */
1903                 dev_dbg(&udev->dev, "usb %ssuspend\n",
1904                                 udev->auto_pm ? "auto-" : "");
1905                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1906                 msleep(10);
1907         }
1908         return status;
1909 }
1910
1911 /*
1912  * If the USB "suspend" state is in use (rather than "global suspend"),
1913  * many devices will be individually taken out of suspend state using
1914  * special "resume" signaling.  This routine kicks in shortly after
1915  * hardware resume signaling is finished, either because of selective
1916  * resume (by host) or remote wakeup (by device) ... now see what changed
1917  * in the tree that's rooted at this device.
1918  *
1919  * If @udev->reset_resume is set then the device is reset before the
1920  * status check is done.
1921  */
1922 static int finish_port_resume(struct usb_device *udev)
1923 {
1924         int     status = 0;
1925         u16     devstatus;
1926
1927         /* caller owns the udev device lock */
1928         dev_dbg(&udev->dev, "finish %sresume\n",
1929                         udev->reset_resume ? "reset-" : "");
1930
1931         /* usb ch9 identifies four variants of SUSPENDED, based on what
1932          * state the device resumes to.  Linux currently won't see the
1933          * first two on the host side; they'd be inside hub_port_init()
1934          * during many timeouts, but khubd can't suspend until later.
1935          */
1936         usb_set_device_state(udev, udev->actconfig
1937                         ? USB_STATE_CONFIGURED
1938                         : USB_STATE_ADDRESS);
1939
1940         /* 10.5.4.5 says not to reset a suspended port if the attached
1941          * device is enabled for remote wakeup.  Hence the reset
1942          * operation is carried out here, after the port has been
1943          * resumed.
1944          */
1945         if (udev->reset_resume)
1946                 status = usb_reset_device(udev);
1947
1948         /* 10.5.4.5 says be sure devices in the tree are still there.
1949          * For now let's assume the device didn't go crazy on resume,
1950          * and device drivers will know about any resume quirks.
1951          */
1952         if (status == 0) {
1953                 devstatus = 0;
1954                 status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
1955                 if (status >= 0)
1956                         status = (status > 0 ? 0 : -ENODEV);
1957         }
1958
1959         if (status) {
1960                 dev_dbg(&udev->dev, "gone after usb resume? status %d\n",
1961                                 status);
1962         } else if (udev->actconfig) {
1963                 le16_to_cpus(&devstatus);
1964                 if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
1965                         status = usb_control_msg(udev,
1966                                         usb_sndctrlpipe(udev, 0),
1967                                         USB_REQ_CLEAR_FEATURE,
1968                                                 USB_RECIP_DEVICE,
1969                                         USB_DEVICE_REMOTE_WAKEUP, 0,
1970                                         NULL, 0,
1971                                         USB_CTRL_SET_TIMEOUT);
1972                         if (status)
1973                                 dev_dbg(&udev->dev, "disable remote "
1974                                         "wakeup, status %d\n", status);
1975                 }
1976                 status = 0;
1977         }
1978         return status;
1979 }
1980
1981 /*
1982  * usb_port_resume - re-activate a suspended usb device's upstream port
1983  * @udev: device to re-activate, not a root hub
1984  * Context: must be able to sleep; device not locked; pm locks held
1985  *
1986  * This will re-activate the suspended device, increasing power usage
1987  * while letting drivers communicate again with its endpoints.
1988  * USB resume explicitly guarantees that the power session between
1989  * the host and the device is the same as it was when the device
1990  * suspended.
1991  *
1992  * If @udev->reset_resume is set then this routine won't check that the
1993  * port is still enabled.  Furthermore, finish_port_resume() above will
1994  * reset @udev.  The end result is that a broken power session can be
1995  * recovered and @udev will appear to persist across a loss of VBUS power.
1996  *
1997  * For example, if a host controller doesn't maintain VBUS suspend current
1998  * during a system sleep or is reset when the system wakes up, all the USB
1999  * power sessions below it will be broken.  This is especially troublesome
2000  * for mass-storage devices containing mounted filesystems, since the
2001  * device will appear to have disconnected and all the memory mappings
2002  * to it will be lost.  Using the USB_PERSIST facility, the device can be
2003  * made to appear as if it had not disconnected.
2004  *
2005  * This facility can be dangerous.  Although usb_reset_device() makes
2006  * every effort to insure that the same device is present after the
2007  * reset as before, it cannot provide a 100% guarantee.  Furthermore it's
2008  * quite possible for a device to remain unaltered but its media to be
2009  * changed.  If the user replaces a flash memory card while the system is
2010  * asleep, he will have only himself to blame when the filesystem on the
2011  * new card is corrupted and the system crashes.
2012  *
2013  * Returns 0 on success, else negative errno.
2014  */
2015 int usb_port_resume(struct usb_device *udev)
2016 {
2017         struct usb_hub  *hub = hdev_to_hub(udev->parent);
2018         int             port1 = udev->portnum;
2019         int             status;
2020         u16             portchange, portstatus;
2021         unsigned        mask_flags, want_flags;
2022
2023         /* Skip the initial Clear-Suspend step for a remote wakeup */
2024         status = hub_port_status(hub, port1, &portstatus, &portchange);
2025         if (status == 0 && !(portstatus & USB_PORT_STAT_SUSPEND))
2026                 goto SuspendCleared;
2027
2028         // dev_dbg(hub->intfdev, "resume port %d\n", port1);
2029
2030         set_bit(port1, hub->busy_bits);
2031
2032         /* see 7.1.7.7; affects power usage, but not budgeting */
2033         status = clear_port_feature(hub->hdev,
2034                         port1, USB_PORT_FEAT_SUSPEND);
2035         if (status) {
2036                 dev_dbg(hub->intfdev, "can't resume port %d, status %d\n",
2037                                 port1, status);
2038         } else {
2039                 /* drive resume for at least 20 msec */
2040                 dev_dbg(&udev->dev, "usb %sresume\n",
2041                                 udev->auto_pm ? "auto-" : "");
2042                 msleep(25);
2043
2044                 /* Virtual root hubs can trigger on GET_PORT_STATUS to
2045                  * stop resume signaling.  Then finish the resume
2046                  * sequence.
2047                  */
2048                 status = hub_port_status(hub, port1, &portstatus, &portchange);
2049
2050  SuspendCleared:
2051                 if (udev->reset_resume)
2052                         want_flags = USB_PORT_STAT_POWER
2053                                         | USB_PORT_STAT_CONNECTION;
2054                 else
2055                         want_flags = USB_PORT_STAT_POWER
2056                                         | USB_PORT_STAT_CONNECTION
2057                                         | USB_PORT_STAT_ENABLE;
2058                 mask_flags = want_flags | USB_PORT_STAT_SUSPEND;
2059
2060                 if (status < 0 || (portstatus & mask_flags) != want_flags) {
2061                         dev_dbg(hub->intfdev,
2062                                 "port %d status %04x.%04x after resume, %d\n",
2063                                 port1, portchange, portstatus, status);
2064                         if (status >= 0)
2065                                 status = -ENODEV;
2066                 } else {
2067                         if (portchange & USB_PORT_STAT_C_SUSPEND)
2068                                 clear_port_feature(hub->hdev, port1,
2069                                                 USB_PORT_FEAT_C_SUSPEND);
2070                         /* TRSMRCY = 10 msec */
2071                         msleep(10);
2072                 }
2073         }
2074
2075         clear_bit(port1, hub->busy_bits);
2076         if (!hub->hdev->parent && !hub->busy_bits[0])
2077                 usb_enable_root_hub_irq(hub->hdev->bus);
2078
2079         if (status == 0)
2080                 status = finish_port_resume(udev);
2081         if (status < 0) {
2082                 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
2083                 hub_port_logical_disconnect(hub, port1);
2084         }
2085         return status;
2086 }
2087
2088 static int remote_wakeup(struct usb_device *udev)
2089 {
2090         int     status = 0;
2091
2092         usb_lock_device(udev);
2093         if (udev->state == USB_STATE_SUSPENDED) {
2094                 dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
2095                 usb_mark_last_busy(udev);
2096                 status = usb_external_resume_device(udev);
2097         }
2098         usb_unlock_device(udev);
2099         return status;
2100 }
2101
2102 #else   /* CONFIG_USB_SUSPEND */
2103
2104 /* When CONFIG_USB_SUSPEND isn't set, we never suspend or resume any ports. */
2105
2106 int usb_port_suspend(struct usb_device *udev)
2107 {
2108         return 0;
2109 }
2110
2111 int usb_port_resume(struct usb_device *udev)
2112 {
2113         int status = 0;
2114
2115         /* However we may need to do a reset-resume */
2116         if (udev->reset_resume) {
2117                 dev_dbg(&udev->dev, "reset-resume\n");
2118                 status = usb_reset_device(udev);
2119         }
2120         return status;
2121 }
2122
2123 static inline int remote_wakeup(struct usb_device *udev)
2124 {
2125         return 0;
2126 }
2127
2128 #endif
2129
2130 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
2131 {
2132         struct usb_hub          *hub = usb_get_intfdata (intf);
2133         struct usb_device       *hdev = hub->hdev;
2134         unsigned                port1;
2135
2136         /* fail if children aren't already suspended */
2137         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
2138                 struct usb_device       *udev;
2139
2140                 udev = hdev->children [port1-1];
2141                 if (udev && udev->can_submit) {
2142                         if (!hdev->auto_pm)
2143                                 dev_dbg(&intf->dev, "port %d nyet suspended\n",
2144                                                 port1);
2145                         return -EBUSY;
2146                 }
2147         }
2148
2149         dev_dbg(&intf->dev, "%s\n", __func__);
2150
2151         /* stop khubd and related activity */
2152         hub_quiesce(hub);
2153         return 0;
2154 }
2155
2156 static int hub_resume(struct usb_interface *intf)
2157 {
2158         struct usb_hub *hub = usb_get_intfdata(intf);
2159
2160         dev_dbg(&intf->dev, "%s\n", __func__);
2161         hub_restart(hub, HUB_RESUME);
2162         return 0;
2163 }
2164
2165 static int hub_reset_resume(struct usb_interface *intf)
2166 {
2167         struct usb_hub *hub = usb_get_intfdata(intf);
2168
2169         dev_dbg(&intf->dev, "%s\n", __func__);
2170         hub_power_on(hub);
2171         hub_restart(hub, HUB_RESET_RESUME);
2172         return 0;
2173 }
2174
2175 /**
2176  * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
2177  * @rhdev: struct usb_device for the root hub
2178  *
2179  * The USB host controller driver calls this function when its root hub
2180  * is resumed and Vbus power has been interrupted or the controller
2181  * has been reset.  The routine marks @rhdev as having lost power.
2182  * When the hub driver is resumed it will take notice and carry out
2183  * power-session recovery for all the "USB-PERSIST"-enabled child devices;
2184  * the others will be disconnected.
2185  */
2186 void usb_root_hub_lost_power(struct usb_device *rhdev)
2187 {
2188         dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
2189         rhdev->reset_resume = 1;
2190 }
2191 EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
2192
2193 #else   /* CONFIG_PM */
2194
2195 static inline int remote_wakeup(struct usb_device *udev)
2196 {
2197         return 0;
2198 }
2199
2200 #define hub_suspend             NULL
2201 #define hub_resume              NULL
2202 #define hub_reset_resume        NULL
2203 #endif
2204
2205
2206 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
2207  *
2208  * Between connect detection and reset signaling there must be a delay
2209  * of 100ms at least for debounce and power-settling.  The corresponding
2210  * timer shall restart whenever the downstream port detects a disconnect.
2211  * 
2212  * Apparently there are some bluetooth and irda-dongles and a number of
2213  * low-speed devices for which this debounce period may last over a second.
2214  * Not covered by the spec - but easy to deal with.
2215  *
2216  * This implementation uses a 1500ms total debounce timeout; if the
2217  * connection isn't stable by then it returns -ETIMEDOUT.  It checks
2218  * every 25ms for transient disconnects.  When the port status has been
2219  * unchanged for 100ms it returns the port status.
2220  */
2221
2222 #define HUB_DEBOUNCE_TIMEOUT    1500
2223 #define HUB_DEBOUNCE_STEP         25
2224 #define HUB_DEBOUNCE_STABLE      100
2225
2226 static int hub_port_debounce(struct usb_hub *hub, int port1)
2227 {
2228         int ret;
2229         int total_time, stable_time = 0;
2230         u16 portchange, portstatus;
2231         unsigned connection = 0xffff;
2232
2233         for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
2234                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2235                 if (ret < 0)
2236                         return ret;
2237
2238                 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
2239                      (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2240                         stable_time += HUB_DEBOUNCE_STEP;
2241                         if (stable_time >= HUB_DEBOUNCE_STABLE)
2242                                 break;
2243                 } else {
2244                         stable_time = 0;
2245                         connection = portstatus & USB_PORT_STAT_CONNECTION;
2246                 }
2247
2248                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2249                         clear_port_feature(hub->hdev, port1,
2250                                         USB_PORT_FEAT_C_CONNECTION);
2251                 }
2252
2253                 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2254                         break;
2255                 msleep(HUB_DEBOUNCE_STEP);
2256         }
2257
2258         dev_dbg (hub->intfdev,
2259                 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2260                 port1, total_time, stable_time, portstatus);
2261
2262         if (stable_time < HUB_DEBOUNCE_STABLE)
2263                 return -ETIMEDOUT;
2264         return portstatus;
2265 }
2266
2267 void usb_ep0_reinit(struct usb_device *udev)
2268 {
2269         usb_disable_endpoint(udev, 0 + USB_DIR_IN);
2270         usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
2271         usb_enable_endpoint(udev, &udev->ep0);
2272 }
2273 EXPORT_SYMBOL_GPL(usb_ep0_reinit);
2274
2275 #define usb_sndaddr0pipe()      (PIPE_CONTROL << 30)
2276 #define usb_rcvaddr0pipe()      ((PIPE_CONTROL << 30) | USB_DIR_IN)
2277
2278 static int hub_set_address(struct usb_device *udev, int devnum)
2279 {
2280         int retval;
2281
2282         if (devnum <= 1)
2283                 return -EINVAL;
2284         if (udev->state == USB_STATE_ADDRESS)
2285                 return 0;
2286         if (udev->state != USB_STATE_DEFAULT)
2287                 return -EINVAL;
2288         retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2289                 USB_REQ_SET_ADDRESS, 0, devnum, 0,
2290                 NULL, 0, USB_CTRL_SET_TIMEOUT);
2291         if (retval == 0) {
2292                 /* Device now using proper address. */
2293                 update_address(udev, devnum);
2294                 usb_set_device_state(udev, USB_STATE_ADDRESS);
2295                 usb_ep0_reinit(udev);
2296         }
2297         return retval;
2298 }
2299
2300 /* Reset device, (re)assign address, get device descriptor.
2301  * Device connection must be stable, no more debouncing needed.
2302  * Returns device in USB_STATE_ADDRESS, except on error.
2303  *
2304  * If this is called for an already-existing device (as part of
2305  * usb_reset_device), the caller must own the device lock.  For a
2306  * newly detected device that is not accessible through any global
2307  * pointers, it's not necessary to lock the device.
2308  */
2309 static int
2310 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2311                 int retry_counter)
2312 {
2313         static DEFINE_MUTEX(usb_address0_mutex);
2314
2315         struct usb_device       *hdev = hub->hdev;
2316         int                     i, j, retval;
2317         unsigned                delay = HUB_SHORT_RESET_TIME;
2318         enum usb_device_speed   oldspeed = udev->speed;
2319         char                    *speed, *type;
2320         int                     devnum = udev->devnum;
2321
2322         /* root hub ports have a slightly longer reset period
2323          * (from USB 2.0 spec, section 7.1.7.5)
2324          */
2325         if (!hdev->parent) {
2326                 delay = HUB_ROOT_RESET_TIME;
2327                 if (port1 == hdev->bus->otg_port)
2328                         hdev->bus->b_hnp_enable = 0;
2329         }
2330
2331         /* Some low speed devices have problems with the quick delay, so */
2332         /*  be a bit pessimistic with those devices. RHbug #23670 */
2333         if (oldspeed == USB_SPEED_LOW)
2334                 delay = HUB_LONG_RESET_TIME;
2335
2336         mutex_lock(&usb_address0_mutex);
2337
2338         /* Reset the device; full speed may morph to high speed */
2339         retval = hub_port_reset(hub, port1, udev, delay);
2340         if (retval < 0)         /* error or disconnect */
2341                 goto fail;
2342                                 /* success, speed is known */
2343         retval = -ENODEV;
2344
2345         if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2346                 dev_dbg(&udev->dev, "device reset changed speed!\n");
2347                 goto fail;
2348         }
2349         oldspeed = udev->speed;
2350
2351         /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2352          * it's fixed size except for full speed devices.
2353          * For Wireless USB devices, ep0 max packet is always 512 (tho
2354          * reported as 0xff in the device descriptor). WUSB1.0[4.8.1].
2355          */
2356         switch (udev->speed) {
2357         case USB_SPEED_VARIABLE:        /* fixed at 512 */
2358                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(512);
2359                 break;
2360         case USB_SPEED_HIGH:            /* fixed at 64 */
2361                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2362                 break;
2363         case USB_SPEED_FULL:            /* 8, 16, 32, or 64 */
2364                 /* to determine the ep0 maxpacket size, try to read
2365                  * the device descriptor to get bMaxPacketSize0 and
2366                  * then correct our initial guess.
2367                  */
2368                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2369                 break;
2370         case USB_SPEED_LOW:             /* fixed at 8 */
2371                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
2372                 break;
2373         default:
2374                 goto fail;
2375         }
2376  
2377         type = "";
2378         switch (udev->speed) {
2379         case USB_SPEED_LOW:     speed = "low";  break;
2380         case USB_SPEED_FULL:    speed = "full"; break;
2381         case USB_SPEED_HIGH:    speed = "high"; break;
2382         case USB_SPEED_VARIABLE:
2383                                 speed = "variable";
2384                                 type = "Wireless ";
2385                                 break;
2386         default:                speed = "?";    break;
2387         }
2388         dev_info (&udev->dev,
2389                   "%s %s speed %sUSB device using %s and address %d\n",
2390                   (udev->config) ? "reset" : "new", speed, type,
2391                   udev->bus->controller->driver->name, devnum);
2392
2393         /* Set up TT records, if needed  */
2394         if (hdev->tt) {
2395                 udev->tt = hdev->tt;
2396                 udev->ttport = hdev->ttport;
2397         } else if (udev->speed != USB_SPEED_HIGH
2398                         && hdev->speed == USB_SPEED_HIGH) {
2399                 udev->tt = &hub->tt;
2400                 udev->ttport = port1;
2401         }
2402  
2403         /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2404          * Because device hardware and firmware is sometimes buggy in
2405          * this area, and this is how Linux has done it for ages.
2406          * Change it cautiously.
2407          *
2408          * NOTE:  If USE_NEW_SCHEME() is true we will start by issuing
2409          * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
2410          * so it may help with some non-standards-compliant devices.
2411          * Otherwise we start with SET_ADDRESS and then try to read the
2412          * first 8 bytes of the device descriptor to get the ep0 maxpacket
2413          * value.
2414          */
2415         for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2416                 if (USE_NEW_SCHEME(retry_counter)) {
2417                         struct usb_device_descriptor *buf;
2418                         int r = 0;
2419
2420 #define GET_DESCRIPTOR_BUFSIZE  64
2421                         buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2422                         if (!buf) {
2423                                 retval = -ENOMEM;
2424                                 continue;
2425                         }
2426
2427                         /* Retry on all errors; some devices are flakey.
2428                          * 255 is for WUSB devices, we actually need to use
2429                          * 512 (WUSB1.0[4.8.1]).
2430                          */
2431                         for (j = 0; j < 3; ++j) {
2432                                 buf->bMaxPacketSize0 = 0;
2433                                 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2434                                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2435                                         USB_DT_DEVICE << 8, 0,
2436                                         buf, GET_DESCRIPTOR_BUFSIZE,
2437                                         USB_CTRL_GET_TIMEOUT);
2438                                 switch (buf->bMaxPacketSize0) {
2439                                 case 8: case 16: case 32: case 64: case 255:
2440                                         if (buf->bDescriptorType ==
2441                                                         USB_DT_DEVICE) {
2442                                                 r = 0;
2443                                                 break;
2444                                         }
2445                                         /* FALL THROUGH */
2446                                 default:
2447                                         if (r == 0)
2448                                                 r = -EPROTO;
2449                                         break;
2450                                 }
2451                                 if (r == 0)
2452                                         break;
2453                         }
2454                         udev->descriptor.bMaxPacketSize0 =
2455                                         buf->bMaxPacketSize0;
2456                         kfree(buf);
2457
2458                         retval = hub_port_reset(hub, port1, udev, delay);
2459                         if (retval < 0)         /* error or disconnect */
2460                                 goto fail;
2461                         if (oldspeed != udev->speed) {
2462                                 dev_dbg(&udev->dev,
2463                                         "device reset changed speed!\n");
2464                                 retval = -ENODEV;
2465                                 goto fail;
2466                         }
2467                         if (r) {
2468                                 dev_err(&udev->dev, "device descriptor "
2469                                                 "read/%s, error %d\n",
2470                                                 "64", r);
2471                                 retval = -EMSGSIZE;
2472                                 continue;
2473                         }
2474 #undef GET_DESCRIPTOR_BUFSIZE
2475                 }
2476
2477                 /*
2478                  * If device is WUSB, we already assigned an
2479                  * unauthorized address in the Connect Ack sequence;
2480                  * authorization will assign the final address.
2481                  */
2482                 if (udev->wusb == 0) {
2483                         for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2484                                 retval = hub_set_address(udev, devnum);
2485                                 if (retval >= 0)
2486                                         break;
2487                                 msleep(200);
2488                         }
2489                         if (retval < 0) {
2490                                 dev_err(&udev->dev,
2491                                         "device not accepting address %d, error %d\n",
2492                                         devnum, retval);
2493                                 goto fail;
2494                         }
2495
2496                         /* cope with hardware quirkiness:
2497                          *  - let SET_ADDRESS settle, some device hardware wants it
2498                          *  - read ep0 maxpacket even for high and low speed,
2499                          */
2500                         msleep(10);
2501                         if (USE_NEW_SCHEME(retry_counter))
2502                                 break;
2503                 }
2504
2505                 retval = usb_get_device_descriptor(udev, 8);
2506                 if (retval < 8) {
2507                         dev_err(&udev->dev, "device descriptor "
2508                                         "read/%s, error %d\n",
2509                                         "8", retval);
2510                         if (retval >= 0)
2511                                 retval = -EMSGSIZE;
2512                 } else {
2513                         retval = 0;
2514                         break;
2515                 }
2516         }
2517         if (retval)
2518                 goto fail;
2519
2520         i = udev->descriptor.bMaxPacketSize0 == 0xff?   /* wusb device? */
2521             512 : udev->descriptor.bMaxPacketSize0;
2522         if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2523                 if (udev->speed != USB_SPEED_FULL ||
2524                                 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2525                         dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
2526                         retval = -EMSGSIZE;
2527                         goto fail;
2528                 }
2529                 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2530                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2531                 usb_ep0_reinit(udev);
2532         }
2533   
2534         retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2535         if (retval < (signed)sizeof(udev->descriptor)) {
2536                 dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
2537                         "all", retval);
2538                 if (retval >= 0)
2539                         retval = -ENOMSG;
2540                 goto fail;
2541         }
2542
2543         retval = 0;
2544
2545 fail:
2546         if (retval) {
2547                 hub_port_disable(hub, port1, 0);
2548                 update_address(udev, devnum);   /* for disconnect processing */
2549         }
2550         mutex_unlock(&usb_address0_mutex);
2551         return retval;
2552 }
2553
2554 static void
2555 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2556 {
2557         struct usb_qualifier_descriptor *qual;
2558         int                             status;
2559
2560         qual = kmalloc (sizeof *qual, GFP_KERNEL);
2561         if (qual == NULL)
2562                 return;
2563
2564         status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2565                         qual, sizeof *qual);
2566         if (status == sizeof *qual) {
2567                 dev_info(&udev->dev, "not running at top speed; "
2568                         "connect to a high speed hub\n");
2569                 /* hub LEDs are probably harder to miss than syslog */
2570                 if (hub->has_indicators) {
2571                         hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2572                         schedule_delayed_work (&hub->leds, 0);
2573                 }
2574         }
2575         kfree(qual);
2576 }
2577
2578 static unsigned
2579 hub_power_remaining (struct usb_hub *hub)
2580 {
2581         struct usb_device *hdev = hub->hdev;
2582         int remaining;
2583         int port1;
2584
2585         if (!hub->limited_power)
2586                 return 0;
2587
2588         remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
2589         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
2590                 struct usb_device       *udev = hdev->children[port1 - 1];
2591                 int                     delta;
2592
2593                 if (!udev)
2594                         continue;
2595
2596                 /* Unconfigured devices may not use more than 100mA,
2597                  * or 8mA for OTG ports */
2598                 if (udev->actconfig)
2599                         delta = udev->actconfig->desc.bMaxPower * 2;
2600                 else if (port1 != udev->bus->otg_port || hdev->parent)
2601                         delta = 100;
2602                 else
2603                         delta = 8;
2604                 if (delta > hub->mA_per_port)
2605                         dev_warn(&udev->dev, "%dmA is over %umA budget "
2606                                         "for port %d!\n",
2607                                         delta, hub->mA_per_port, port1);
2608                 remaining -= delta;
2609         }
2610         if (remaining < 0) {
2611                 dev_warn(hub->intfdev, "%dmA over power budget!\n",
2612                         - remaining);
2613                 remaining = 0;
2614         }
2615         return remaining;
2616 }
2617
2618 /* Handle physical or logical connection change events.
2619  * This routine is called when:
2620  *      a port connection-change occurs;
2621  *      a port enable-change occurs (often caused by EMI);
2622  *      usb_reset_device() encounters changed descriptors (as from
2623  *              a firmware download)
2624  * caller already locked the hub
2625  */
2626 static void hub_port_connect_change(struct usb_hub *hub, int port1,
2627                                         u16 portstatus, u16 portchange)
2628 {
2629         struct usb_device *hdev = hub->hdev;
2630         struct device *hub_dev = hub->intfdev;
2631         struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
2632         u16 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
2633         int status, i;
2634  
2635         dev_dbg (hub_dev,
2636                 "port %d, status %04x, change %04x, %s\n",
2637                 port1, portstatus, portchange, portspeed (portstatus));
2638
2639         if (hub->has_indicators) {
2640                 set_port_led(hub, port1, HUB_LED_AUTO);
2641                 hub->indicator[port1-1] = INDICATOR_AUTO;
2642         }
2643  
2644         /* Disconnect any existing devices under this port */
2645         if (hdev->children[port1-1])
2646                 usb_disconnect(&hdev->children[port1-1]);
2647         clear_bit(port1, hub->change_bits);
2648
2649 #ifdef  CONFIG_USB_OTG
2650         /* during HNP, don't repeat the debounce */
2651         if (hdev->bus->is_b_host)
2652                 portchange &= ~USB_PORT_STAT_C_CONNECTION;
2653 #endif
2654
2655         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2656                 status = hub_port_debounce(hub, port1);
2657                 if (status < 0) {
2658                         if (printk_ratelimit())
2659                                 dev_err (hub_dev, "connect-debounce failed, "
2660                                                 "port %d disabled\n", port1);
2661                         goto done;
2662                 }
2663                 portstatus = status;
2664         }
2665
2666         /* Return now if nothing is connected */
2667         if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2668
2669                 /* maybe switch power back on (e.g. root hub was reset) */
2670                 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2
2671                                 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
2672                         set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
2673  
2674                 if (portstatus & USB_PORT_STAT_ENABLE)
2675                         goto done;
2676                 return;
2677         }
2678
2679         for (i = 0; i < SET_CONFIG_TRIES; i++) {
2680                 struct usb_device *udev;
2681
2682                 /* reallocate for each attempt, since references
2683                  * to the previous one can escape in various ways
2684                  */
2685                 udev = usb_alloc_dev(hdev, hdev->bus, port1);
2686                 if (!udev) {
2687                         dev_err (hub_dev,
2688                                 "couldn't allocate port %d usb_device\n",
2689                                 port1);
2690                         goto done;
2691                 }
2692
2693                 usb_set_device_state(udev, USB_STATE_POWERED);
2694                 udev->speed = USB_SPEED_UNKNOWN;
2695                 udev->bus_mA = hub->mA_per_port;
2696                 udev->level = hdev->level + 1;
2697                 udev->wusb = hub_is_wusb(hub);
2698
2699                 /* set the address */
2700                 choose_address(udev);
2701                 if (udev->devnum <= 0) {
2702                         status = -ENOTCONN;     /* Don't retry */
2703                         goto loop;
2704                 }
2705
2706                 /* reset and get descriptor */
2707                 status = hub_port_init(hub, udev, port1, i);
2708                 if (status < 0)
2709                         goto loop;
2710
2711                 /* consecutive bus-powered hubs aren't reliable; they can
2712                  * violate the voltage drop budget.  if the new child has
2713                  * a "powered" LED, users should notice we didn't enable it
2714                  * (without reading syslog), even without per-port LEDs
2715                  * on the parent.
2716                  */
2717                 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
2718                                 && udev->bus_mA <= 100) {
2719                         u16     devstat;
2720
2721                         status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
2722                                         &devstat);
2723                         if (status < 2) {
2724                                 dev_dbg(&udev->dev, "get status %d ?\n", status);
2725                                 goto loop_disable;
2726                         }
2727                         le16_to_cpus(&devstat);
2728                         if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
2729                                 dev_err(&udev->dev,
2730                                         "can't connect bus-powered hub "
2731                                         "to this port\n");
2732                                 if (hub->has_indicators) {
2733                                         hub->indicator[port1-1] =
2734                                                 INDICATOR_AMBER_BLINK;
2735                                         schedule_delayed_work (&hub->leds, 0);
2736                                 }
2737                                 status = -ENOTCONN;     /* Don't retry */
2738                                 goto loop_disable;
2739                         }
2740                 }
2741  
2742                 /* check for devices running slower than they could */
2743                 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
2744                                 && udev->speed == USB_SPEED_FULL
2745                                 && highspeed_hubs != 0)
2746                         check_highspeed (hub, udev, port1);
2747
2748                 /* Store the parent's children[] pointer.  At this point
2749                  * udev becomes globally accessible, although presumably
2750                  * no one will look at it until hdev is unlocked.
2751                  */
2752                 status = 0;
2753
2754                 /* We mustn't add new devices if the parent hub has
2755                  * been disconnected; we would race with the
2756                  * recursively_mark_NOTATTACHED() routine.
2757                  */
2758                 spin_lock_irq(&device_state_lock);
2759                 if (hdev->state == USB_STATE_NOTATTACHED)
2760                         status = -ENOTCONN;
2761                 else
2762                         hdev->children[port1-1] = udev;
2763                 spin_unlock_irq(&device_state_lock);
2764
2765                 /* Run it through the hoops (find a driver, etc) */
2766                 if (!status) {
2767                         status = usb_new_device(udev);
2768                         if (status) {
2769                                 spin_lock_irq(&device_state_lock);
2770                                 hdev->children[port1-1] = NULL;
2771                                 spin_unlock_irq(&device_state_lock);
2772                         }
2773                 }
2774
2775                 if (status)
2776                         goto loop_disable;
2777
2778                 status = hub_power_remaining(hub);
2779                 if (status)
2780                         dev_dbg(hub_dev, "%dmA power budget left\n", status);
2781
2782                 return;
2783
2784 loop_disable:
2785                 hub_port_disable(hub, port1, 1);
2786 loop:
2787                 usb_ep0_reinit(udev);
2788                 release_address(udev);
2789                 usb_put_dev(udev);
2790                 if ((status == -ENOTCONN) || (status == -ENOTSUPP))
2791                         break;
2792         }
2793         if (hub->hdev->parent ||
2794                         !hcd->driver->port_handed_over ||
2795                         !(hcd->driver->port_handed_over)(hcd, port1))
2796                 dev_err(hub_dev, "unable to enumerate USB device on port %d\n",
2797                                 port1);
2798  
2799 done:
2800         hub_port_disable(hub, port1, 1);
2801         if (hcd->driver->relinquish_port && !hub->hdev->parent)
2802                 hcd->driver->relinquish_port(hcd, port1);
2803 }
2804
2805 static void hub_events(void)
2806 {
2807         struct list_head *tmp;
2808         struct usb_device *hdev;
2809         struct usb_interface *intf;
2810         struct usb_hub *hub;
2811         struct device *hub_dev;
2812         u16 hubstatus;
2813         u16 hubchange;
2814         u16 portstatus;
2815         u16 portchange;
2816         int i, ret;
2817         int connect_change;
2818
2819         /*
2820          *  We restart the list every time to avoid a deadlock with
2821          * deleting hubs downstream from this one. This should be
2822          * safe since we delete the hub from the event list.
2823          * Not the most efficient, but avoids deadlocks.
2824          */
2825         while (1) {
2826
2827                 /* Grab the first entry at the beginning of the list */
2828                 spin_lock_irq(&hub_event_lock);
2829                 if (list_empty(&hub_event_list)) {
2830                         spin_unlock_irq(&hub_event_lock);
2831                         break;
2832                 }
2833
2834                 tmp = hub_event_list.next;
2835                 list_del_init(tmp);
2836
2837                 hub = list_entry(tmp, struct usb_hub, event_list);
2838                 kref_get(&hub->kref);
2839                 spin_unlock_irq(&hub_event_lock);
2840
2841                 hdev = hub->hdev;
2842                 hub_dev = hub->intfdev;
2843                 intf = to_usb_interface(hub_dev);
2844                 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
2845                                 hdev->state, hub->descriptor
2846                                         ? hub->descriptor->bNbrPorts
2847                                         : 0,
2848                                 /* NOTE: expects max 15 ports... */
2849                                 (u16) hub->change_bits[0],
2850                                 (u16) hub->event_bits[0]);
2851
2852                 /* Lock the device, then check to see if we were
2853                  * disconnected while waiting for the lock to succeed. */
2854                 usb_lock_device(hdev);
2855                 if (unlikely(hub->disconnected))
2856                         goto loop;
2857
2858                 /* If the hub has died, clean up after it */
2859                 if (hdev->state == USB_STATE_NOTATTACHED) {
2860                         hub->error = -ENODEV;
2861                         hub_stop(hub);
2862                         goto loop;
2863                 }
2864
2865                 /* Autoresume */
2866                 ret = usb_autopm_get_interface(intf);
2867                 if (ret) {
2868                         dev_dbg(hub_dev, "Can't autoresume: %d\n", ret);
2869                         goto loop;
2870                 }
2871
2872                 /* If this is an inactive hub, do nothing */
2873                 if (hub->quiescing)
2874                         goto loop_autopm;
2875
2876                 if (hub->error) {
2877                         dev_dbg (hub_dev, "resetting for error %d\n",
2878                                 hub->error);
2879
2880                         ret = usb_reset_composite_device(hdev, intf);
2881                         if (ret) {
2882                                 dev_dbg (hub_dev,
2883                                         "error resetting hub: %d\n", ret);
2884                                 goto loop_autopm;
2885                         }
2886
2887                         hub->nerrors = 0;
2888                         hub->error = 0;
2889                 }
2890
2891                 /* deal with port status changes */
2892                 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
2893                         if (test_bit(i, hub->busy_bits))
2894                                 continue;
2895                         connect_change = test_bit(i, hub->change_bits);
2896                         if (!test_and_clear_bit(i, hub->event_bits) &&
2897                                         !connect_change && !hub->activating)
2898                                 continue;
2899
2900                         ret = hub_port_status(hub, i,
2901                                         &portstatus, &portchange);
2902                         if (ret < 0)
2903                                 continue;
2904
2905                         if (hub->activating && !hdev->children[i-1] &&
2906                                         (portstatus &
2907                                                 USB_PORT_STAT_CONNECTION))
2908                                 connect_change = 1;
2909
2910                         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2911                                 clear_port_feature(hdev, i,
2912                                         USB_PORT_FEAT_C_CONNECTION);
2913                                 connect_change = 1;
2914                         }
2915
2916                         if (portchange & USB_PORT_STAT_C_ENABLE) {
2917                                 if (!connect_change)
2918                                         dev_dbg (hub_dev,
2919                                                 "port %d enable change, "
2920                                                 "status %08x\n",
2921                                                 i, portstatus);
2922                                 clear_port_feature(hdev, i,
2923                                         USB_PORT_FEAT_C_ENABLE);
2924
2925                                 /*
2926                                  * EM interference sometimes causes badly
2927                                  * shielded USB devices to be shutdown by
2928                                  * the hub, this hack enables them again.
2929                                  * Works at least with mouse driver. 
2930                                  */
2931                                 if (!(portstatus & USB_PORT_STAT_ENABLE)
2932                                     && !connect_change
2933                                     && hdev->children[i-1]) {
2934                                         dev_err (hub_dev,
2935                                             "port %i "
2936                                             "disabled by hub (EMI?), "
2937                                             "re-enabling...\n",
2938                                                 i);
2939                                         connect_change = 1;
2940                                 }
2941                         }
2942
2943                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
2944                                 clear_port_feature(hdev, i,
2945                                         USB_PORT_FEAT_C_SUSPEND);
2946                                 if (hdev->children[i-1]) {
2947                                         ret = remote_wakeup(hdev->
2948                                                         children[i-1]);
2949                                         if (ret < 0)
2950                                                 connect_change = 1;
2951                                 } else {
2952                                         ret = -ENODEV;
2953                                         hub_port_disable(hub, i, 1);
2954                                 }
2955                                 dev_dbg (hub_dev,
2956                                         "resume on port %d, status %d\n",
2957                                         i, ret);
2958                         }
2959                         
2960                         if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
2961                                 dev_err (hub_dev,
2962                                         "over-current change on port %d\n",
2963                                         i);
2964                                 clear_port_feature(hdev, i,
2965                                         USB_PORT_FEAT_C_OVER_CURRENT);
2966                                 hub_power_on(hub);
2967                         }
2968
2969                         if (portchange & USB_PORT_STAT_C_RESET) {
2970                                 dev_dbg (hub_dev,
2971                                         "reset change on port %d\n",
2972                                         i);
2973                                 clear_port_feature(hdev, i,
2974                                         USB_PORT_FEAT_C_RESET);
2975                         }
2976
2977                         if (connect_change)
2978                                 hub_port_connect_change(hub, i,
2979                                                 portstatus, portchange);
2980                 } /* end for i */
2981
2982                 /* deal with hub status changes */
2983                 if (test_and_clear_bit(0, hub->event_bits) == 0)
2984                         ;       /* do nothing */
2985                 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
2986                         dev_err (hub_dev, "get_hub_status failed\n");
2987                 else {
2988                         if (hubchange & HUB_CHANGE_LOCAL_POWER) {
2989                                 dev_dbg (hub_dev, "power change\n");
2990                                 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
2991                                 if (hubstatus & HUB_STATUS_LOCAL_POWER)
2992                                         /* FIXME: Is this always true? */
2993                                         hub->limited_power = 1;
2994                                 else
2995                                         hub->limited_power = 0;
2996                         }
2997                         if (hubchange & HUB_CHANGE_OVERCURRENT) {
2998                                 dev_dbg (hub_dev, "overcurrent change\n");
2999                                 msleep(500);    /* Cool down */
3000                                 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
3001                                 hub_power_on(hub);
3002                         }
3003                 }
3004
3005                 hub->activating = 0;
3006
3007                 /* If this is a root hub, tell the HCD it's okay to
3008                  * re-enable port-change interrupts now. */
3009                 if (!hdev->parent && !hub->busy_bits[0])
3010                         usb_enable_root_hub_irq(hdev->bus);
3011
3012 loop_autopm:
3013                 /* Allow autosuspend if we're not going to run again */
3014                 if (list_empty(&hub->event_list))
3015                         usb_autopm_enable(intf);
3016 loop:
3017                 usb_unlock_device(hdev);
3018                 kref_put(&hub->kref, hub_release);
3019
3020         } /* end while (1) */
3021 }
3022
3023 static int hub_thread(void *__unused)
3024 {
3025         /* khubd needs to be freezable to avoid intefering with USB-PERSIST
3026          * port handover.  Otherwise it might see that a full-speed device
3027          * was gone before the EHCI controller had handed its port over to
3028          * the companion full-speed controller.
3029          */
3030         set_freezable();
3031
3032         do {
3033                 hub_events();
3034                 wait_event_freezable(khubd_wait,
3035                                 !list_empty(&hub_event_list) ||
3036                                 kthread_should_stop());
3037         } while (!kthread_should_stop() || !list_empty(&hub_event_list));
3038
3039         pr_debug("%s: khubd exiting\n", usbcore_name);
3040         return 0;
3041 }
3042
3043 static struct usb_device_id hub_id_table [] = {
3044     { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
3045       .bDeviceClass = USB_CLASS_HUB},
3046     { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
3047       .bInterfaceClass = USB_CLASS_HUB},
3048     { }                                         /* Terminating entry */
3049 };
3050
3051 MODULE_DEVICE_TABLE (usb, hub_id_table);
3052
3053 static struct usb_driver hub_driver = {
3054         .name =         "hub",
3055         .probe =        hub_probe,
3056         .disconnect =   hub_disconnect,
3057         .suspend =      hub_suspend,
3058         .resume =       hub_resume,
3059         .reset_resume = hub_reset_resume,
3060         .pre_reset =    hub_pre_reset,
3061         .post_reset =   hub_post_reset,
3062         .ioctl =        hub_ioctl,
3063         .id_table =     hub_id_table,
3064         .supports_autosuspend = 1,
3065 };
3066
3067 int usb_hub_init(void)
3068 {
3069         if (usb_register(&hub_driver) < 0) {
3070                 printk(KERN_ERR "%s: can't register hub driver\n",
3071                         usbcore_name);
3072                 return -1;
3073         }
3074
3075         khubd_task = kthread_run(hub_thread, NULL, "khubd");
3076         if (!IS_ERR(khubd_task))
3077                 return 0;
3078
3079         /* Fall through if kernel_thread failed */
3080         usb_deregister(&hub_driver);
3081         printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
3082
3083         return -1;
3084 }
3085
3086 void usb_hub_cleanup(void)
3087 {
3088         kthread_stop(khubd_task);
3089
3090         /*
3091          * Hub resources are freed for us by usb_deregister. It calls
3092          * usb_driver_purge on every device which in turn calls that
3093          * devices disconnect function if it is using this driver.
3094          * The hub_disconnect function takes care of releasing the
3095          * individual hub resources. -greg
3096          */
3097         usb_deregister(&hub_driver);
3098 } /* usb_hub_cleanup() */
3099
3100 static int descriptors_changed(struct usb_device *udev,
3101                 struct usb_device_descriptor *old_device_descriptor)
3102 {
3103         int             changed = 0;
3104         unsigned        index;
3105         unsigned        serial_len = 0;
3106         unsigned        len;
3107         unsigned        old_length;
3108         int             length;
3109         char            *buf;
3110
3111         if (memcmp(&udev->descriptor, old_device_descriptor,
3112                         sizeof(*old_device_descriptor)) != 0)
3113                 return 1;
3114
3115         /* Since the idVendor, idProduct, and bcdDevice values in the
3116          * device descriptor haven't changed, we will assume the
3117          * Manufacturer and Product strings haven't changed either.
3118          * But the SerialNumber string could be different (e.g., a
3119          * different flash card of the same brand).
3120          */
3121         if (udev->serial)
3122                 serial_len = strlen(udev->serial) + 1;
3123
3124         len = serial_len;
3125         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
3126                 old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
3127                 len = max(len, old_length);
3128         }
3129
3130         buf = kmalloc(len, GFP_NOIO);
3131         if (buf == NULL) {
3132                 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
3133                 /* assume the worst */
3134                 return 1;
3135         }
3136         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
3137                 old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
3138                 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
3139                                 old_length);
3140                 if (length != old_length) {
3141                         dev_dbg(&udev->dev, "config index %d, error %d\n",
3142                                         index, length);
3143                         changed = 1;
3144                         break;
3145                 }
3146                 if (memcmp (buf, udev->rawdescriptors[index], old_length)
3147                                 != 0) {
3148                         dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
3149                                 index,
3150                                 ((struct usb_config_descriptor *) buf)->
3151                                         bConfigurationValue);
3152                         changed = 1;
3153                         break;
3154                 }
3155         }
3156
3157         if (!changed && serial_len) {
3158                 length = usb_string(udev, udev->descriptor.iSerialNumber,
3159                                 buf, serial_len);
3160                 if (length + 1 != serial_len) {
3161                         dev_dbg(&udev->dev, "serial string error %d\n",
3162                                         length);
3163                         changed = 1;
3164                 } else if (memcmp(buf, udev->serial, length) != 0) {
3165                         dev_dbg(&udev->dev, "serial string changed\n");
3166                         changed = 1;
3167                 }
3168         }
3169
3170         kfree(buf);
3171         return changed;
3172 }
3173
3174 /**
3175  * usb_reset_device - perform a USB port reset to reinitialize a device
3176  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
3177  *
3178  * WARNING - don't use this routine to reset a composite device
3179  * (one with multiple interfaces owned by separate drivers)!
3180  * Use usb_reset_composite_device() instead.
3181  *
3182  * Do a port reset, reassign the device's address, and establish its
3183  * former operating configuration.  If the reset fails, or the device's
3184  * descriptors change from their values before the reset, or the original
3185  * configuration and altsettings cannot be restored, a flag will be set
3186  * telling khubd to pretend the device has been disconnected and then
3187  * re-connected.  All drivers will be unbound, and the device will be
3188  * re-enumerated and probed all over again.
3189  *
3190  * Returns 0 if the reset succeeded, -ENODEV if the device has been
3191  * flagged for logical disconnection, or some other negative error code
3192  * if the reset wasn't even attempted.
3193  *
3194  * The caller must own the device lock.  For example, it's safe to use
3195  * this from a driver probe() routine after downloading new firmware.
3196  * For calls that might not occur during probe(), drivers should lock
3197  * the device using usb_lock_device_for_reset().
3198  *
3199  * Locking exception: This routine may also be called from within an
3200  * autoresume handler.  Such usage won't conflict with other tasks
3201  * holding the device lock because these tasks should always call
3202  * usb_autopm_resume_device(), thereby preventing any unwanted autoresume.
3203  */
3204 int usb_reset_device(struct usb_device *udev)
3205 {
3206         struct usb_device               *parent_hdev = udev->parent;
3207         struct usb_hub                  *parent_hub;
3208         struct usb_device_descriptor    descriptor = udev->descriptor;
3209         int                             i, ret = 0;
3210         int                             port1 = udev->portnum;
3211
3212         if (udev->state == USB_STATE_NOTATTACHED ||
3213                         udev->state == USB_STATE_SUSPENDED) {
3214                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
3215                                 udev->state);
3216                 return -EINVAL;
3217         }
3218
3219         if (!parent_hdev) {
3220                 /* this requires hcd-specific logic; see OHCI hc_restart() */
3221                 dev_dbg(&udev->dev, "%s for root hub!\n", __func__);
3222                 return -EISDIR;
3223         }
3224         parent_hub = hdev_to_hub(parent_hdev);
3225
3226         set_bit(port1, parent_hub->busy_bits);
3227         for (i = 0; i < SET_CONFIG_TRIES; ++i) {
3228
3229                 /* ep0 maxpacket size may change; let the HCD know about it.
3230                  * Other endpoints will be handled by re-enumeration. */
3231                 usb_ep0_reinit(udev);
3232                 ret = hub_port_init(parent_hub, udev, port1, i);
3233                 if (ret >= 0 || ret == -ENOTCONN || ret == -ENODEV)
3234                         break;
3235         }
3236         clear_bit(port1, parent_hub->busy_bits);
3237         if (!parent_hdev->parent && !parent_hub->busy_bits[0])
3238                 usb_enable_root_hub_irq(parent_hdev->bus);
3239
3240         if (ret < 0)
3241                 goto re_enumerate;
3242  
3243         /* Device might have changed firmware (DFU or similar) */
3244         if (descriptors_changed(udev, &descriptor)) {
3245                 dev_info(&udev->dev, "device firmware changed\n");
3246                 udev->descriptor = descriptor;  /* for disconnect() calls */
3247                 goto re_enumerate;
3248         }
3249   
3250         if (!udev->actconfig)
3251                 goto done;
3252
3253         ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3254                         USB_REQ_SET_CONFIGURATION, 0,
3255                         udev->actconfig->desc.bConfigurationValue, 0,
3256                         NULL, 0, USB_CTRL_SET_TIMEOUT);
3257         if (ret < 0) {
3258                 dev_err(&udev->dev,
3259                         "can't restore configuration #%d (error=%d)\n",
3260                         udev->actconfig->desc.bConfigurationValue, ret);
3261                 goto re_enumerate;
3262         }
3263         usb_set_device_state(udev, USB_STATE_CONFIGURED);
3264
3265         for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
3266                 struct usb_interface *intf = udev->actconfig->interface[i];
3267                 struct usb_interface_descriptor *desc;
3268
3269                 /* set_interface resets host side toggle even
3270                  * for altsetting zero.  the interface may have no driver.
3271                  */
3272                 desc = &intf->cur_altsetting->desc;
3273                 ret = usb_set_interface(udev, desc->bInterfaceNumber,
3274                         desc->bAlternateSetting);
3275                 if (ret < 0) {
3276                         dev_err(&udev->dev, "failed to restore interface %d "
3277                                 "altsetting %d (error=%d)\n",
3278                                 desc->bInterfaceNumber,
3279                                 desc->bAlternateSetting,
3280                                 ret);
3281                         goto re_enumerate;
3282                 }
3283         }
3284
3285 done:
3286         return 0;
3287  
3288 re_enumerate:
3289         hub_port_logical_disconnect(parent_hub, port1);
3290         return -ENODEV;
3291 }
3292 EXPORT_SYMBOL_GPL(usb_reset_device);
3293
3294 /**
3295  * usb_reset_composite_device - warn interface drivers and perform a USB port reset
3296  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
3297  * @iface: interface bound to the driver making the request (optional)
3298  *
3299  * Warns all drivers bound to registered interfaces (using their pre_reset
3300  * method), performs the port reset, and then lets the drivers know that
3301  * the reset is over (using their post_reset method).
3302  *
3303  * Return value is the same as for usb_reset_device().
3304  *
3305  * The caller must own the device lock.  For example, it's safe to use
3306  * this from a driver probe() routine after downloading new firmware.
3307  * For calls that might not occur during probe(), drivers should lock
3308  * the device using usb_lock_device_for_reset().
3309  */
3310 int usb_reset_composite_device(struct usb_device *udev,
3311                 struct usb_interface *iface)
3312 {
3313         int ret;
3314         int i;
3315         struct usb_host_config *config = udev->actconfig;
3316
3317         if (udev->state == USB_STATE_NOTATTACHED ||
3318                         udev->state == USB_STATE_SUSPENDED) {
3319                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
3320                                 udev->state);
3321                 return -EINVAL;
3322         }
3323
3324         /* Prevent autosuspend during the reset */
3325         usb_autoresume_device(udev);
3326
3327         if (iface && iface->condition != USB_INTERFACE_BINDING)
3328                 iface = NULL;
3329
3330         if (config) {
3331                 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
3332                         struct usb_interface *cintf = config->interface[i];
3333                         struct usb_driver *drv;
3334
3335                         if (cintf->dev.driver) {
3336                                 drv = to_usb_driver(cintf->dev.driver);
3337                                 if (drv->pre_reset)
3338                                         (drv->pre_reset)(cintf);
3339         /* FIXME: Unbind if pre_reset returns an error or isn't defined */
3340                         }
3341                 }
3342         }
3343
3344         ret = usb_reset_device(udev);
3345
3346         if (config) {
3347                 for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
3348                         struct usb_interface *cintf = config->interface[i];
3349                         struct usb_driver *drv;
3350
3351                         if (cintf->dev.driver) {
3352                                 drv = to_usb_driver(cintf->dev.driver);
3353                                 if (drv->post_reset)
3354                                         (drv->post_reset)(cintf);
3355         /* FIXME: Unbind if post_reset returns an error or isn't defined */
3356                         }
3357                 }
3358         }
3359
3360         usb_autosuspend_device(udev);
3361         return ret;
3362 }
3363 EXPORT_SYMBOL_GPL(usb_reset_composite_device);